Pigments & Recipes PDF Book N°2

Page 1

PIGMENTS

RECIPES

David Damour

DAVID DAMOUR

The secrets of the painter's craft

This 470 page book, illustrated with 1500 original photographs, illuminates the painter's activity in a new light, proposing to discover, as you have never seen, the universe of colors with more than 400 pigments, 200 modern materials, 200 recipes and tricks, as well as many step-by-step for more than 30 painting techniques. The intention of this book is to provide a complete panorama of the painter's world and the paintings uses by him, including contemporary coatings for a perfect understanding of their constituents, as paints require a wide range of raw materials, starting from the minerals to the pigments by the modern binders and the contemporary materials. This knowledge will help you to choose with pertinence and discernment the trade materials. Writing such a book was self-evident because the material at our disposal is numerous at the beginning of this twenty-first century. This book is the result of research begun 25 years ago, it could not have been published before, because the author has carried out many aging tests; These made it possible to develop original paintings, he gives us here the recipes. From the physics of paintings to the secrets of making pigments from minerals, from grinding paints to cooking oils, and using materials and tools to explore the entire pictorial field. The author has written this book to highlight the influence and importance of the pigments, ins and outs of all the colors that surrounds us. He tries to answer the questions asked by colored matter, in order to sensitize all those who love painting and colors, by transmitting the secrets of such a rich activity, in order to familiarize themselves by acquiring solid knowledge that " Free the artist in front of his only creative thought ", as Marc Havel rightly said, because painting can not be improvised, like any artistic activity. The author has been painting since the age of 9 (1975 and has been writing since the age of 14 (1981). He studied physics chemistry paintings at the Pierre and Marie Curie University at Jussieu (Paris), then for 2 years the writings on pigments and the craft of the painter at the Forney Library, He also studied at the "cabinet des dessins du Louvre" and at the School of Fine Arts (Paris).He likes to formulate paintings and paint colorful paintings

93 € ISBN 979-10-96990-06-1

THE SECRETS OF THE PAINTER'S CRAFT

Artist, creator, painter, teacher, restorer, student, decorator or simply passionate about colors, this book will open doors of a fascinating world of pigments in multiple colors, it will immerse you in the colorful universe of the materials.

2021 DAVID DAMOUR Éditions David Damour

PIGMENTS

RECIPES

THE SECRETS OF THE PAINTER'S CRAFT in the 21 st

2021


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DAVID DAMOUR

PIGMENTS & RECIPES The Secrets of the Painter's Craft of the XXIst Century Artists

ED DAVID DAMOUR



ACKNOWLEDGMENTS

All my gratitude goes to Jacques Maroger. All his life he improved the famous Rubens medium or Rubens gel - (whatever his name, its a mixture of putty varnish and siccatized oil, which gives a gel) - and to Marc Havel to have reinforced me in the idea that the art of painting is something other than pressing the paint of a tube and then applying it to a support. In 1989, when I read the book of Jacques Maroger: "À la recherche des secrets des grands peintres" on mastic's mediums and wax's mediums, I made my pigments from minerals for a year, I grounded my paintings on the marble, but the mediums I used at this time did not seem the rubens gel medium or the Venetian's medium; Three years later, Claude Yvel's book "Le métier retrouvé des maîtres" was published, and in the same year "Le lustre de la main" by Abraham Pincas, where both detail and photographs explain the experiments that had begun three years earlier, this allowed me to know that I was going in the right direction and for that I thank them infinitely. I pay tribute here to Abraham Pincas, a great educator and a great colorist who brought a lot to the craft painter's and who left us in April 2015. I would like to express my gratitude to all those I have met over years and who have strengthened me in my approach, to all the authors I have read and who have inspired me and indirectly advised ; to my relatives who strongly encouraged me to persevere and to always give my best.


COPYRIGHT AND DISCLAIMER

PigmentsRecettes https://pigmentsrecettes.com Email :

contact@pigmentsrecettes.com

Writing and Graphic Design © 2008-2018. David Damour

Despite the thousands of hours of work and the care taken to correct the mistakes, you will certainly find misspellings and typos in this book, because perfection is not of this world. If you find errors and point out to me by email damour@pigmentsrecettes.com, I would correct them and thus I could improve future prints, thank you. I wanted to send you the photos of this book on digital support (for those who have chosen the "Deluxe" version), because despite the care taken to print the pigments, it is impossible to transcribe on paper The color beauty of colored powders.

This book contains 1624 unique and original photos, minerals, pigments, painting materials and works © 2016 David Damour. Photos of minerals of my collection are all under © 2016 David Damour. Circa 100 photographs in the book are taken ©2016 Attila Gazo from Master Pigments® with their written permission.

For the other photos I borrowed on Wikipedia®, I stipulate under it on a case-by-case the names of their respective authors.

License Creative Commons Attribution and ShareAlike for all vector illustrations that I have made specifically for the book. Use them if you like, but if you change the thank you to credit.

Warning

No responsibility is assumed by the author for any injury or damage to persons or property and can not be seen as a question of liability on the part of the product, negligence or otherwise, or the use or the Exploitation of all the methods, products, instructions or ideas contained in this book.

Legal deposit june 2021


PREAMBLE

Dear readers, I gave to this book as title, "the secrets of the of the artist's craft of the XXIst century", because I show you The painter's craft as you have never read it where I distilled there, number of recipes and tricks never mentioned in detail in a book, in order to differentiate it well from other books on the painter's craft. In the"XXIst century", because many of the materials dealt with in this book are contemporary and some like rare earth pigments are not all still available at retail. The technique of painting evolves every day in our time (2016), because many researchers are trying to understand and extract the maximum of the materials of the XXIst century, to be convinced just read only one "European-coatings.com newsletter" to understand how research is dense and rich about pigments, materials and coating techniques because coating necessarily express paint film and therefore the painting her self. This work is the result of many years of studies, assiduous research and experiments of the materials of the painter. You will find detailed steps explanation in making paintings for art from the minerals and the use of materials and tools related to the creation of art. Understanding artistic and creative processes will give you more freedom and spontaneity in the execution of your art, enabling you to more readily grasp the ins and outs of paintings, so you would choose with more discerning the commercial materials.

I want to point out that this book is not a book on a particular brand (if you find throughout your reading some of them it is because I wanted to simplify things), its a didactic book on technique, materials and their uses in easel painting and monumental painting. You certainly do not find any existing pigments in this book, because there are more than 600; but I have ambitions to write a book very soon with all existing pigments and outstanding (that you can buy) so the painter can use them. I have found since 2001 a real passion for the art of the painter, many websites abound on this theme, it is a very good thing, because for the layman, extract from this mass of information the substantive knowledge or a guideline where to begin is arduous. I have written this book to guide all those who make artistic painting as a passion in order to help them to grasp this complex activity at first sight in order to acquire more freedom thanks to this knowledge. I wish you a very good reading and as much pleasure to read and to use this book that I got to writing him. David Damour 2021 Painter, Writer, Illustrator Creator of Pigments and Dyes Creator of 100% natural soaps


The ego - Enluminure and dye juice on paper. 28 X 20 cm ©2003 David Damour. Private collection.


PRÉFACE

"The need for art dates back to about a hundred thousand years, to modern man, although more and more evidence shows that the Neanderthal man was also able to develop symbolic and even artistic intentions." Phillippe Walter. L’art-chimie page 38 [1]. I would add, modestly, artistic intentions of symbolic's nature". Like his ancestors, the artist Painter of the XXIth century can realize a considerable number of recipes of painting with all the raw materials that nature and chemistry give him, without omitting in our time and for the future, nano Materials (silica, pigment such as nano zinc white, etc.). I will give you here, all the ones I have tested, formulated or developed during my research that I have undertaken since 1988. This represents more than 200 recipes, tips and tricks of all techniques combined, that you can adapt for your work. Some of them require a lot of rigor in the formulation, ie the dosages are very important, others on the contrary can be interpreted, keeping in mind that the purpose of all these recipes must serve the work and nothing else. In case of doubt, always be guided by simplicity, a recipe even very elaborate must contain only ingredients that go along with the technique and the desired result, it is a simple question of logic. Example: if I want to make a watercolor recipe, I would avoid introducing casein into the formulation, which is a strong animal glue based on milk protein and which dry very quickly, while watercolor is a paint based on vegetable gum. Start by gathering all the ingredients together by enumerating them on a sheet to verify at first if you have sufficient quantities. The knowledge of these materials and recipes will allow you unparalleled freedom of execution, more mastery in the accomplishment of your art day-to-day. Weigh and then take notes of all your tests, because getting a finished product is one thing, knowing how to remake it is another things. It takes time to know all art materials, because in fact the lack of this knowledge of sound scientists mixtures, is the biggest obstacle that you may encounter. An immense freedom is acquired once and fore-

ver, provided by focus seriously and assiduously the study of all substances and materials constituents in all paints, because as said Madeleine Hours, French museum curator and historian of art "The work of art is material before being message. " I am aware of the complication that this can engender for the painter who wants to create, that's all. But we have reached a pivotal point in how to apprehend the painting. Nowadays, in the twenty-first century, the many technological and chemical aspects of paintings are well known in the literature, which means that the production of paintings has finally changed from "art" to "science". I think it's a fair return to the roots. Because five centuries ago in the time of Leonardo da Vinci (1452-1519), the painter was a scientist, at least a scholar for his time and in relation to his contemporaries, he knew how to recognize the materials he used, although there were no academies, nor school of art, the artist learned from a master, more rarely alone as an autodidact like Nicolas Poussin for example. It certainly took a considerable amount of time. Nowadays things have become even more complex, with the fields of organic chemistry and nanotechnologies. For the painter to know all these applications fields is impossible. I find it logical that those who are able to grasp these technologies, or at least understand them, transmit to others and popularize them (in the sense of simplification to make them comprehensible) if necessary, in order to make the paintings of the twenty-first century, such as microemulsions, 1K polyurethanes, high performance pigments, rare earth pigments, etc. ... As said so rightly Marc Havel, in 1979, in his book "the technique of painting"Basically, the technique of painting is reduced with the use of mediums, with some few basic rules that quickly become instinctive and release the artist in front of his only creative thought ". This is still true in 2016. Despite the profusion of technical paints, it remains important to maintain simplicity, although it is necessary to create works borrow and spontaneity, in this century that will have seen them born.


TIPS AND LISTS

TABLES OF CONTENTS Antifoaming ........................................................ 98 Wetting Agents ................................................... 99

Tips and Tricks Workshop ................................. 14 Polarity - An Important Term ........................... 15 Melting Point of Some Substances ................... 36

T

PHYSICS OF PAINTINGS

pH List of Some Substances ............................ 112

The refractive index ......................................... 100

Refractive Index List ........................................ 136

Covering and coloring power ........................... 101

Filler's Characteristics ......................................284

The Concentration Pigmentary Volumique .... 102

Pigment's Oil Absorption List .......................... 309

Hardness and Adhesive Tests ......................... 104

Empty Tubes Capacities List ............................ 314

Fillers in Paintings ........................................... 104

Advantages and disadvantages of paints ......... 318

Pigments Properties in Light .......................... 106

Pigment's Density List ...................................... 347

Pigment Dispersion ......................................... 108

Grinded Oil Paint Tubes .................................. 378

The particles shape of the pigments ............... 109 Final Grinding of Pigments ............................. 110

HE MATERIALS

Flocculation ...................................................... 111

Solvent Phase Binders List ................................. 16

The pH meter ................................................... 113

The Hydrogen Potential ................................... 112

Aqueous Binders List ......................................... 17 Synthetic Binders and Adjuvants ...................... 18 Oleaginous Binders ............................................ 25

THE MINERALS

.................................................. 114

Paintings with oleaginous binders .................... 30

From Minerals to Pigments ............................... 116

Siccatives ............................................................ 31

Preparation Materials ........................................ 117

The Essences ...................................................... 38

Ochre Crushing .................................................. 118

Alternative solvents ...................................... 38

Putting Ochre in Powder .................................... 119

The solubility index ...................................... 39

Fine Grinding ..................................................... 120

The Balsams ....................................................... 52

Minerals Powdering ........................................... 122

Natural Resins ................................................... 58

Purification of Minerals ..................................... 123

Synthetic Resins ................................................. 64

The Levigation ................................................... 124

Polaroids Solubility ....................................... 67

Extra Fine Grinding Result ............................... 128

Natural Gums ..................................................... 74 Animal Glues ...................................................... 82 Vegetable Adhesives ........................................... 85 Waxes ................................................................. 86 Preventol® ON Extra ......................................... 91 Conservatives ..................................................... 92 Mordants ............................................................ 94 Plasticizers .......................................................... 95 Surfactants and Dispersants .............................. 96 pH Compensator ................................................ 97

PIGMENTS

Pigments Collection ........................................... 131 Pigments ............................................................ 132 Colour Index C.I ................................................. 134 High Performance Pigments ............................. 138 Periodic Table of High P. Pigments ................... 141 Rare Earth Pigments .......................................... 145 Cerium Pigments ............................................... 146


TABLES OF CONTENTS Classical Inorganic Pigments ............................ 150

Oils Purification ................................................ 303

Blue Pigments .................................................... 151

The Oils Yellowing ............................................ 304

White Pigments .................................................. 163

Different Drying Oils ......................................... 305

Yellow Pigments ................................................. 171

result of oils sedimentation ............................... 307

Red Pigments ..................................................... 179 Green Pigments ................................................. 185 Ochres ................................................................ 195 Synthetic Iron Oxides ....................................... 202 The Earths.......................................................... 203 Grey Pigments ................................................... 209 Orange Pigments ............................................... 214 Purple Pigments ................................................ 219 Brown Pigments ................................................ 225 Black Pigments .................................................. 230 Mica & Pearlescent Pigments ........................... 235 Glimmers and Scintillants Pigments ................ 237 Fluorescents Pigments ...................................... 238 Acids and Solvents Dyes .................................... 242 Phosphorescent Pigments ................................. 243 Organic Lacquered Pigments ............................ 244 Pigments From Animals .................................... 245 Natural Plants Pigments ................................... 252 Metallic Pigments .............................................. 267 Dyes and Synthetic Pigments ............................ 270 Sudan© Dyes .................................................... 278 Orasol© Dyes .................................................... 280 Proteiform Pigments ......................................... 281

PAINTS GRINDING Marble & Mullers ............................................. 308 List of Oil absorption rates of pigments .......... 309 Aqueous grinding to make all the paints ......... 310 Paints Grinding ................................................. 311 Pigment Grinding With Oil .............................. 312 Natural Malachite grinding in Oil .................... 313 The Empty Tubes .............................................. 314 Tubing grounded paintings ............................. 315

AND PAINTS RECIPES TECHNIQUES

........................................ 316

The properties of paints ................................... 318 Enluminure or Miniatura ................................ 320 The Tüchlein ..................................................... 322 Dye Juices ......................................................... 325 Casein Paint ...................................................... 328 Hide Glue Paint ................................................ 331 The Inks............................................................. 337 The Cera Colla .................................................. 341 Watercolor Buckets .......................................... 346 Watercolor in Tube ........................................... 347

F

ILLERS

The Gouache ..................................................... 350

AND INERT MATERIALS

The Pastel ......................................................... 355

Fillers ............................................................... 285

Silicate Binder Paint ......................................... 358

Coagulators ....................................................... 291

The Encaustic ................................................... 362

Inert Substrates ................................................ 295

The Acrylic ........................................................ 369

PREPARATION OF OILS

Preparation of Oils ............................................ 300 Clear Oil Cooking Detail .................................... 301 Other Siccative Oil Recipes ............................... 302

The alkyd paint ................................................. 373 The Oil Paint ..................................................... 376 The Polyurethanes ........................................... 380 The Fresco ........................................................ 383 Lean Temperas ................................................. 388


TABLES OF CONTENTS Micro-emulsions ...................................................... 390 Surfactants Agents ............................................ 392

IXATIVES FAND VARNISHES

Components of 21st Century Emulsions ........... 393

Fixative for Pastels and others ................................. 433

Modern Emulsion Recipes ................................ 393

Fixative for Black Strokes .......................................... 433

Oily Varnishes or Vernis Gras .......................... 394

Varnishes ................................................................... 434 Varnishes for Oil Painting ......................................... 435

T

HE SUPPORTS

Varnish with Shellac ................................................. 436

Canvas Supports ........................................................ 397

Lacquered Martin's Varnish ...................................... 438

Wooden Supports .......................................................398

Flat Matt varnish ....................................................... 439

Synthetic Supports .................................................... 399

Varnish with Amber .................................................. 440

Aluminum Supports .................................................. 400 Tension of the Canvases ............................................ 401

S

UPPORTS PRÉPARATION The Sizes .................................................................... 402 Printing or Imprimature ........................................... 405

White Varnish also known as Crystal Varnish .......... 437

GILDING

Mixtion Recipe ........................................................... 441 Example of gilding with Acrylic ................................ 443

A

CCESSORIES

Glue Skin ground for Canvas .................................... 406

Masks, Gloves and Soaps .......................................... 444

Coatings for Wood ..................................................... 407

Empty Tubes and Palette .......................................... 445

Acrylic grounds and gesso ........................................ 408

The Painter's Knives .................................................. 446

Lean coatings for canvas ........................................... 409 Structured coatings ................................................... 410 Polishing coatings with horsetail............................... 411 The Marouflages ....................................................... 412

M

EDIUMS FOR PAINTS

BRUSHES AND PAINT BRUSHES

Anatomy of Brushes and Paint Brushes .................... 447 Ferrules and sleeve lengths ....................................... 448 Conservation and Maintenance of Brushes .............. 449 Making a Brush in 14 Steps ....................................... 450

Wax Saponification ................................................... 416

Best Brushes on 2021 ................................................ 452

The Venetian Medium ............................................... 417

Spalters ...................................................................... 456

The Rubens Medium ................................................. 418

Brushes for Oil Painting ............................................ 458

Damour's Medium with Sandaraque ........................ 420

Specific brushes ......................................................... 460

Synthetic Mediums .................................................... 424 Polyglycol to improve paints ..................................... 422 Acrylic mediums for textures and impasto ............... 423 Gel and acrylic paints mediums ................................ 424 Preparation of gels .................................................... 426 Formulation of acrylic impasto gels and mediums .. 429 What to avoid doing with acrylic mediums .............. 430 acrylic/casein paint ................................................... 432

ESSENTIAL BOOKS BIBLIOGRAPHY AND INTERNET LINKS SUPPLIERS

.................................................................. 461

............................. 462

........................................................... 468

INDEX

........................................................................ 470


The vegetable man - Miniatura with white of egg and dye juice on paper 28 X 20 cm © 2000 David Damour. Private collection.


RUBENS GEL MEDIUM

Black oil

Chios mastic varnish


THE PAINTER'S CRAFT

13

THE ART WORK IS MATTER BEFORE BEING MESSAGE Madeleine Hours* How many artists have I heard them say: "I want to paint, I do not want to prepare my paintings and varnishes, it's a waste of time."But if you think about this, its like a musician who wants to play an instrument without learning the Solfeggio. Can you imagine Mozart or Bach not having learned the key of fa, for example. It is to see a problem where there is none. It does not prevent, these are often the same artists who ask for advice on the use of such materials or such products, they spend their time looking for ways to paint a picture or achieve such texture because they do not have the technique to his execution. It is the stumbling block on which they stumble whenever they start to work. I notice how hard they struggle with technical problems, rather than spend more time for creation, because they don't have the basics knowledges, they know little or less which is their own craft. It reminds me the myth of Sisyphus, who had to forever roll to the top of a hill, a rock which came down each time before he reach the top. After 25 years of studies on the painter's craft, I noticed a "Not Knowing"characteristic related to the craft of the painter, as if not knowing his own craft was inevitable. Any other corporation worker knows and has the basics of his profession, indeed it could not be otherwise if he wants to be able to work and earn a living. The necessary infrastructures for the learning of his craft exist, the painter have few schools adapted to teach him and to show him the way, at the School of Fine Arts in Paris (France) where the excellent Abraham Pincas From 1985 until 2011 and a few private workshops, little attention is paid to this apprenticeship, which was at one time an obligatory passage for every painter who chose painting and the arts as craft. But it was not always so. If we look back, the painter studied many years (i.e., 7 years, or even more, if we count travel study abroad) as much as a physician, Leonardo Da Vinci studied at the risk of his life, the anatomy for 20 years, moreover, the painter and the doctor shared the same corporation until the 18th century. Its an evidence that the painter's craft was something serious and recognized with rules and objectives to be achieved through a strong learning : "a craft". I have notice since 2001 a real passion for everything that constitutes art painting, many websites exists on the subject and that's a good thing. The number of suppliers has doubled, on this subject the masters of the past were able to make long journeys to

find their pigments and materials, today a consultation on the "Web" and we are delivered home from all over the world, what more incredible, So why not take advantage of it. However, for the beginner to extract from this mass of information a guideline where to start is arduous, that is why I wrote this book, to help and show to everyone who like painting, how to apprehend an activity complex at its first sight and acquire through this knowledge more freedom and ease in its execution. For centuries, the artist (assisted by a pupil or a disciple) prepared his supports, his colors, his varnishes and sometimes his brushes, but at the beginning of the eighteenth century in France the secrets of the craft were lost (Italy did lose their customs in the nineteenth). The causes are multifactorial of course and the invention of the flexible empty tube of paint, in 1841, has a large part in this long descent to oblivion, but one of the great causes is that the last vestiges which constituted "the craft" were in the hands of painters who did not transmit their secrets to the new generations because it was an advantage that should not be lost compared to the competition from other workshops. When we thinks that the painters of the fifteenth to the seventeenth century (Rubens for example) painted for eternity and never delegated the grinding, the cooking of oil or the making of a medium from the moment their signature was engaged, we realizes how much "thze knowledge and its execution" are essential and how its important to share it.

In France Jean François Léonor Mérimée (17571836), reopened the way towards 1830, but we really began to reclaim the painter's craft based with the research of Jacques Maroger in 1948 and his collaboration with Marc Havel and Raoul dufy; Later in the twentieth century, artists-researchers contributed greatly to this recovery to arrive with Nicolas Wacker in 1969 then towards the years 1985 Abraham Pincas and Claude Yvel. For the twenty-first century, Patrice de Pracontal in 2008 and Jean-Pierre Brazs in 2011. I realize that only one book is not enough to write about the subject and that is why I plan to do another one after this, which will include all that is missing in this book, it will be like a logical suite.

* Madeleine Hours (1913-2005), is a French curator of museum and historian of art, specialist in the restoration of paintings. Former director of the research laboratory of the Museums of France.


14

TIPS AND TRICKS Tip for determining an unknown material

Take a high-quality photo of the material, which you do not know the nature of and then drag your photo on the Google © images page [4], you will have a track of other images of the material in question, giving you an idea of what you have in your hands.

How to reuse turpentine 3-4x

Instead of wasting, when cleaning or rinsing your brushes in white spirit or turpentine, instead of throwing away these solvents, transfer them to a separate flask and leave for 1 week or even 15 days, you will see that after a certain amount of time, the liquid becomes clear like water again, it is thus reusable.

How to manage the cloths safely

They must be drowned in a container of water, thus avoiding any possible self-ignition.

Stackable disposable pallets

at a very low cost, any plastic receptacle can be used as a pallet when you are cooking, pick up the plastic wrappers, then cut them into 10 cm squares. You can brush them with pure acrylic binder to make peelable pallets, once dry, you can remove the acrylic film, all the paint residues will come with. Remember to brush the back of the square to be able to pull the acrylic film once you want to remove it.

How to keep fresh, remaining paintings

of a work session for the next session 1-Plunge your pallet into water for 3 cm. 2-Put the pallet in a plastic bag and put it in the refrigerator 3-Cover with aluminum paper, the paint in its place or arrange it in aluminum paper and then fold the 4 edges. 4-Use very small flasks.

To know if a coat of paint is hardened and can be repainted with a new coat Apply on the dry painted surface, a sheet of silk paper with squirrel brush or with a squeegee. It can be covered with a new coat of paint, if the sheet can be completely removed.

Delay the hardening time of the oils Add a few drops of pine oil or clove.

Tip to avoid breathing dust from powder pigments When you receive your pigments, they are packaged in plastic bags or plastic jars. The best way to avoid dangerous dust from pulverulent materials is to completely impregnate the pigment with a liquid such as water, so there is no longer any undesirable dust. For plastic bags, cut one of the corners of the bag at 45 °, then place it on the opposite side of the cut and introduce as much water as necessary, squeeze the bag and shake until all the powder Is moistened. With a chisel cut out all the plastic and collect the wet paste for potting, let or not evaporate the water and add a preservative in case ; these pigments prepared as pulp are no longer dangerous from the point of view of pulverulence. For non-toxic materials, cut one of the corners of the bag and then empty it into the container. Wear all the same a mask, because all the dust without exception is harmful, they can be deposited on the mucous membranes of the nose and in the lungs, risking to asphyxiate us if the oxygen can no more flow into the organism.

Tips for keeping liquids and paints

Leave as little space as possible in your bottles, you will keep your binders, varnishes and solvents longer. As the quantity decreases, take a new bottle of smaller capacity and so on. That's how I keep all my varnishes and liquids, like that I never throw anything.

Preserving paints in pots

Fill the pots with half of the paint filled with water, or solvent depend on the phase of the paint, then close the container and spill the head upside down.

Reduce photo-activity of Titanium

The photoactivity of Titanium TiO2 pigments is reduced by the addition of silica or alumina particles to form a barrier layer against oxidation-reduction reactions, oxidation and reduction of the material.

To put in pot sepiolite or other powder


POLAR OR NON-POLAR

15

What is Polarity I want to clarify from the beginning of this book an important and recurring term of the painter's craft, the polarity is one of those terms that deserves clarification. I use it because it is the most relevant and precise word to characterize the antagonistic characteristic of a substance towards lean substances (water or aqueous substances) or fats (oils or oleaginous substances). Polarity determines whether a substance is soluble in water. A polar substance is a substance that has two different poles, such as a magnet. Thus, when two polar substances are mixed, the poles of the substances attract each other, and consequently they mix. This is how a substance dissolves in water. A molecule of water is an example of a molecule created by a covalent bond. The water is composed by an oxygen atom and two hydrogen atoms, whith the Chemical Formula H2O. Water is an example of a polar molecule by excellence. We denote the slightly negative end of each link by d- and the slightly positive end by d +. The symbol d means dipole. The polarity of the water can attract other water molecules through the attraction between the + and -. These attractions are called hydrogen bonds. An hydrogen bond is the force that is exerted between two molecules (intermolecular force), it is not a bond inside a molecule. These hydrogen bonds are about 20 times weaker than the covalent bonds. Weak bonds such as hydrogen bonds allow short contact between the molecules. The molecules join, react together and separate. These weak bonds play a major role in the stabilization of several large molecules in organic matter, as in emulsions. Since these bonds are weak, they break down and are constantly reconstituted during normal physiological reactions, which is why aqueous paints rapidly sediment and often need to be agitated to restore their original state. Water is the king of solvents, because it has a certain universality. This is due to the polarity of its water molecules and their tendency to form hydrogen bonds with many other molecules.

A covalent bond is a form by chemical bond between two non-metal atoms, such as hydrogen and oxygen, which is characterized by the sharing of electrons between two or more atoms. These weak bonds play an important role in the stabilization of molecules in organic matter. Because these bonds are weak, they are constantly broken and reformed during normal physical reactions, which is why it is necessary to agitate the emulsions in order to restore them to their original state. Oil molecules are made up of carbon and hydrogen atoms, called triglycerides, because they seems like a comb with three teeth. The oil has no positive or negative poles that is why it can not bind and stabilize with water because it can not form hydrogen bonds with it. Substances which contain no pole, are called apolar or non-polar substances. Oil is indeed an apolar or nonpolar substance, which is why it does not dissolve or bind with water. To overcome this disadvantage it is necessary to add in the oil-water mixtures, an emulsifier and a surfactant, which are molecules having two distinct characteristics, this name is called amphiphilia, a part possesses a lipophilic characteristic (it retains fat ) it is apolar, the other a characteristic of hydrophilicity (which has an affinity for water) it is polar. These amphiphilic molecules will encompass the oil droplets by touching their lipophilic part, and dispersing these coated droplets in water, by binding to the water molecules thanks to their hydrophilic part. It is a cooperative reaction unilaterally beneficial for the two elements in order to make them cooperate to create a temporary stable state, because over time the molecules will separate. The oil and the water bind, interact and separate, which is why it is often necessary to restore their initial states of the emulsions, by agitation in order to make the amphiphilic molecules interact. Thus, there are a few surfactants, including phosphatidylcholine, also called lecithin (in reference to the Greek word Lekithos, meaning egg yolk), lauric sodium sulphate or lauric acid, the main fatty acid of coconut oil, etc. .... See surfactants.


16

LIST OF SOLVENT-PHASE BINDERS Binders are pure liquid substances or mixed with gums, resins or any other product which constitute the paints and which are mixed with pigments, the substances we use to cover surfaces, we paint on canvas, wood, paper, etc. ... It can also be said agglutinant or vehicule by speaking about binders, since it is indeed water or oil which makes it possible to agglutinate the pigments, serving as vehicle. The binder agglutinates the colored powders, pigments, in order

to apply them to various surfaces. It ensures the cohesion and adhesion of the layers, films or paint films to the supports. A binder is the combination of a liquid with a solid, which results in a more or less stable suspension even in oil paints, because the pigments are ground with pure oil, but are not used like that but in conjunction with a medium, a mixture of resins and oils which are siccatives or not, or with a saponified wax or other solid adjuvants

which are liquefied in order to apply them easily to the supports. For water it is the mixture with it of a gum, albumin, animal or vegetable glue, acrylic resin, cellulosic resin or other materials which constitute the binder and also referred as "aqueous binders", "waterborne binder" or "aqueous binders with polar substances", the latter term being more commonly used by artworks restorers.

BINDERS IN SOLVENT PHASE 1. Acrylic or vinyl solvent-borne paints, eg Plexisol, Paraloid, etc. ... 2. Cellulosic and Ethylcellulosic paints in solvent phase with ethyl or butyl acetate or ethanol. 3. Oil painting from walnut, linen or any other oils 4. Paint of pure resin such as mastic resin mixture with a pigment and some alcohol or essence as solvent and diluent. 5. Temperas or fat emulsions of water in oil 6. Fat distemper : mixtures of hide or skin glue, with oil and water 7. Oleo casein paints : Casein emulsified with 3:1 Tung Oil or China wood oil with water 8. Mixtures of saponified waxes and black oil

9. Encaustic : pure wax or wax mixed with resin and turpentine at hot or cold 10. Oily varnish: mixture of natural gum, resins and oils 11. Alkyd paint in solvent phase also known as "glycerophthalic" 12. Polyurethane paints with hexamethylene diisocyanate (HDI) 13. Epoxy paints in bi-component or single-component form 14. Phenolic resins, polycondensation of formic aldehyde and phenols. Paints 13 and 14 must be baked in oven.

Substances for making binders


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LIST OF AQUEOUS BINDERS

There are about 20 water painting techniques (as much as there are families of gums, glues and components that can be dissolved in water), whether they are natural or synthetic polymers. An aqueous binder is said "water binder" (In its liquid or pasty form) when the solvent and the diluent are water. Mixtures of the substances listed below are considered as aqueous binders.

BINDERS IN POLAR PHASE 1. Simple mixtures of gum and water 2. Enluminure : composed by albumen : egg 3. 4. 5. 6. 7. 8. 9. 10. 11. 12.

white alone or mixed with gums Lean tempera : oil-in-water emulsion using egg yolk Distemper : technique based on glue of skins or other natural glues Casein : milk converted into lean white cheese then solubilized using an alkali Aqueous mixtures based on synthetic ethylcellulosic polar phase glues such as Klucels and Tyloses (see watercolor) Dry pastel with based gum tragacanth Watercolor, mixture of gum arabic or cherry of high quality and water Modern gouache: mixture of gum tragacanth, gum arabic, albumin, talc or kaolin, anti-foaming and water Simple inks and aqueous Lavis with saponified gum-lacquer Cera-Colla: technique of liquid saponified wax in water with an alkali Juices of dyes "lacquered" (for example with alum) applied to canvas or paper

13. Tüchlein : aqueous technique (used from 15th

14. 15. 16. 17. 18.

19. 20. 21. 22. 23.

Very light Italian Apricot tree gum

Liquefied Parchment Glue = Distemper

to 18th century), is a mixture of skin glue and vegetable dyes, imitating the art of tapestry on paper, fine linen or silk, Bruegel is an eminent representative of this Technique [11]. The Secco : Gouache technique on dry plaster Synthetic resins (acrylics, vinyls, etc.) with water in polar phase Alkyd and 1K polyurethane resins : mixed paints in aqueous phase Painting with lime: technique of lime milk on dry plaster previously moistened The pure fresco or buon fresco, where water serves as a vehicle and diluent for lime and pigments applied to a fresh coating, smoothed with trowel The fresco with lime : pigments mixed with water of lime and then applied on a fresh coating called "intonaco" Distemper of lime on fresh plaster or dry plaster: Painting emulsified water and glue, egg or casein, mixed together or separately Modern binders and inks with PEG Polyethylene Glycol Etc. ...

Very High Tragacanth Quality binder

Cera-colla Saponified wax and water

Universal binder "Damour's Klache" 2 gums + 1 protein


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SYNTHETIC BINDERS The era of organic and synthetic chemistry was born around 1824, with Friedrich Wöhler, a German chemist born in 1800, in Eschersheim near Frankfurt. He was the first to define the basic notions of isomers, polymers and allotropies, and he was also interested in silicones. The way was open. In 2016, more than 200 resins, essences and other synthetic materials for artistic use can be counted. The term "synthetic binders" refers to all liquids, resins and organic materials obtained by chemical reaction or polymerization, which are based on molecules of low molecular mass : monomers which form, by the bonds thereof, compounds of high molecular mass called macromolecules ". The perfect understanding of these components is organic chemistry and far exceeds the knowledge of artist painters (me too). The technical data gathered here come from technical data sheets of the various manufacturers of resins and other synthetic components. Only the day-to-day use of such materials makes it possible to deduce certain lessons for an artistic use. Here is the result of my empirical research on the use of these materials, very interesting for the execution of artworks. The products can wear different names according to the manufacturers, I deliver here throughout this book, the generic names of these materials. The active substance acts as reference. [13]

Plextol® B 500 - K 360 - D 498 et D 540 Originally acrylics are obtained from naphtha, a petroleum cut resulting from the refining of petroleum, from which benzene, ethylene and propylene are extracted. Propylene will be used particularly for the manufacture of acrylic acids and derivatives thereof. The methacrylic monomer is obtained by chloromethylation of methyl chloride and benzyl chloride which gives methyl methacrylic, an important constituent of the acrylic binders. The polyacrylics have the general formula (-CH2-CHCOOR-)N and are obtained by polymerization of ethyl, methyl and butyl acrylate n(H2C=HC-COOR) to give methyl, ethyl, and butyl polyacrylates -H2C- CH|COOR)n which are the main constituents of the best acrylic resins for painters. Of all the water-based acrylic binders I have used, Plextol® are the most reliable. The difference between the various references is viscosity, particle diameter, percentage solids, pH, density and percentage elongation. They are used for the sizing of substrates, for marouflages, for the consolidation of wall surfaces, for painting and restoration of paintings as a cold or very low temperature doubling agent for the consolidation of paintings, and Adhesives for punctual refixing. These are really versatile resins.

It is a pure acrylic resin dispersion based on ethyl acrylate (60%), methyl methacrylate (39%) and ethyl methacrylate (1%). It is soluble in aromatic hydrocarbons such as toluene and xylene in order to increase viscosity and tackiness and to decrease its drying time. Ketones and esters such as ethyl acetate and amyl are dilutable with water. Moreover, its paint films are resistant to mineral oils, but they are reversible in acetone and toluene. It produces a transparent, colorless and flexible film. The Plextol B500 makes it possible to make paints highly resistant to external aggressions, non-saponifiable, non-yellowing and resistant to friction. Plextol B500 is also used as an additive for hydraulic compounds and for the formulation of emulsions with other resins such as Plextol K 360 as well as with polyvinyl alcohols and with polyvinyl acetate emulsions. As a light thickening agent, Tylose MH 300 can be used, as well as for making very large artworks sizes, which increases the time for the openings paint (see below Tylose), there are other coagulating agents such as Rohagit® SD 15, Laponite and thickeners ASE 60. Dry extracts about 50%.

PLEXTOL B 500 It is a milky white liquid of medium viscosity with good penetration and excellent wetting properties. Plextol B500 and its adjuvants


SYNTHETIC BINDERS Viscosity: 1100 4500 mPas PH: 9.5 ± 0.5 / Density: 1.08 Kg / l Particle diameter: ~ 0.1 μm Minimum film-forming temperature: ~ 7 ° C Properties of the film (after drying in air, not pigmented): Tensile test (DIN 53 455) (Transverse head speed: 100 mm / min) Tensile strength σR ~ 7.5 N / mm2 Elongation at break εR ~ 600% ie 1 cm for a dry film of 6 cm. Temperature at the maximum amortization TΛmax ~ + 29 ° C. Shear modulus G 20 ° C ~ 130 N / mm2. Plextol B 500 is also particularly proven as a binder for high quality cellular concrete coatings. Acrylic resin plextol B500

pure Plextol layer after drying - 21 years film

PLEXTOL K 360 (formerly D360)

Acrylic butyl acrylate dispersion having superior adhesiveness to Plextol B 500 and faster drying time. Ideal for marouflages and as insulation of aqueous prints on fabrics. Totally insoluble in water after drying. Reversible in acetone and toluene. It dries very quickly and can be reactivated with toluene. Add 5 ml of rohagit per liter to compensate for defects due to the presence of water. Dry extracts between 59 and 61%, the strongest of all plextols®. Viscosity: <1000 mPas. PH: 2.0 to 3.5 Density: 1.02 Kg / l. Average particle size: 0.4 μm. Elongation at break:> 1000%. Adhesive strength: ~ 4.5 N / 25 mm2 Minimum film-forming temperature: <0 ° C Film softening temperature: -8 ° C Thermal stability: ~ 25 h at 50 ° C I use Plextol K 360 for all my marouflages and as

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plasticizer, it is a very sticky resin, it can stay a very long in this state.

Pure Plextol K 360, 2-mm thick layer after 24 hours. It becomes transparent after 3 days. 2016

PLEXTOL D 498

High viscosity acrylic dispersion based on butyl acrylate. Its application fields are the same as Plextol B 500. Its adhesiveness and viscosity are superior to Plextol B 500, but it is less flexible than Plextol K 360. I have stored this binder on an Stretching of a dry film of a experimental mixture of plextol B500 + Plextol K360 + antifoaming agent basis for close to 8 years and it did not move because it was stored away from light and frost in full pots. Dry extract 50 ± 1%. Viscosity: 3000 - 10000 mPas. PH: 9.0 ± 0.5. Density: 1.05 Kg / l .. Average particle size ~ 0.15μm. Minimum film-forming temperature: ~ 5 ° C. Film softening temperature: - 26 ° C. Elongation at break: up to about 400%. I use it as a binder for paint pigments.

PLEXTOL D 540

Aqueous emulsion dispersion of a methacrylate acid; Acrylic ester copolymer. Plextol D 540 contains a highly pure anionic emulsifier system free from solvents or plasticizers. It is very resistant to saponification. Dry extract 50 ± 1% - Density: 1.06 Kg / l. Viscosity: 3000 - 10000 mPas - pH: 9.0 ± 0.5 Appearance of film: clear, non-sticky Water absorption (24 hours): 9% Elongation at break: 250% Average particle size: ~ 0.15 μm Minimum Film Temperature: 20 ° C


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SYNTHETIC AND GELIFIANT BINDERS TYLOSE® MH300

It is Organic Methylhydroxyethyl Cellulose. It is in the form of soluble granules only in cold water, compatible with all natural gums and starches, as well as acrylic and vinyl emulsions. Is an anionic substance = negatively charged, carrying a large number of negatively charged radicals, that are polyanions. I use it for the sizing of paper and textile supports especially for cotton, but also as an aqueous binder. Restorers use it as a gelling agent to clean paper. It is also an anti-flocculant agent for aqueous paints. Camphor or sodium benzoate can be added as a preservative in the binder. Minimum active ingredient. 99.5% Maximum humidity: 10% Maximum chloride (NaCl): 0.50% Sulfate ash: 1.0% Heavy metals: max. 20 ppm PH: (in 1% solution): 6.0 to 8.0 Viscosity: 400 mPas

CARBOPOL® EZ2 or CARBOPOL® ULTREZ 21

Carbopol® EZ2 is a polymeric acid solder based on a modified acrylic. It makes it possible to produce non-fibrous structuring gels with very little water, thus at an incredibly low level, it can change the water into a non-dusty, smooth, non-filamentous and crystalline gel. EZ2 Carbopol® emulsions were stable and paste for many years and even if the heat is high.Only 0.10% of Carbopol allows to create gels of high viscosity and these do not drizzle even on supports with high verticality. The conditions under which Carbopol® EZ2 develops its characteristics are in a polar binder such as water : Operating temperatures should not exceed 85 ° C. I use Carbopol EZ2 for several centimeters thick pastes and to stick fibers and all sorts of objects on my paintings such as sand, glass beads, glass flakes, etc. ... It's an incredible medium to be used without moderation while keeping in mind that it is not food grade. Its final pH must be 5 or more. No soluble salt should be placed in its presence. Viscosity in water: 0.2% min of the concentration: 10.000mPas maximum 30.000 - 0.5% min of the concentration: 50.000 mPas maximum 70.000

Tylose in water solution

TYLOSE ® C 6000 - TYLOSE ® MH 1000 TYLOSE ® MH 30.000 vith retarders

Tylose C6000: Carboxymethyl Highly purified sodium cellulose (CMC) with a viscosity of 6000 mPas. Tylose® MH 1000: Methylhydroxyethyl cellulose with viscosity 1000 mPas and Tylose MHB 30,000 Methylhydroxyethylcellulose with viscosity = 3000 mPas pH: 6 to 8. Sodium: 6.5 - 9.7% High viscosity anionic substance : negatively charged and carrying a large number of negatively charged radicals, which are called polyanions. The advantage of this Tylose C 6000 is that it can be dissolved in water at any temperature. These three Tyloses are used according to the desired dough thickness. The difference between them is the viscosity and the drying time. The most viscous being the Tylose C6000 while the more pasty for gels is the Tylose MHB 30,000. Put camphor in the binder. It forms gels when heated to 50-60 ° C.

CARBOPOL EZ 2

BENECEL ™ A4C

Benecel methylcellulose (TM) and hydroxy propyl methylcellulose (HPMC) are high purity products derived from water-soluble cellulose designed for use in many formulations. The main functional properties of Benecel ™ and HPMC are their reversibility of hot water gelling, aqueous binder making and water retention, providing a barrier to oil, but also as a thickener, emulsion formation and stabilizing paint films.


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SYNTHETIC BINDERS These functions may vary depending on the type, viscosity, percentage used and polymer conversion conditions. Benecel ™ and HPMC derivatives are also widely used to control the viscosity of paints. Thermal gelation occurs at temperatures of 48°C. Benecel HPMC is compatible with most natural gums such as xanthan, starch, guar gum, carrageenans and alginates. Salt: NaCl, max. 0.8%. Chlorides, max 0.5%. Decomposition temperature > 220 ° C Density at 2%, 20°C = 1.0032 g / ml Surface tension, 0.1%, 20°C = 45 - 55 mN/m pH of a 2% solution at 20°C = 5.5-8.0 A synergistic increase in viscosity is obtained with the addition of xanthan gum. 1% benecel K200M is compatible with 6 to 12% of ammonium lauryl sulfate but not with Alkylpolyglucosides

Steps for dispersing Benecel in water

1 Heat 1/5 of the total amount of water required for the solution to 80 - 90 °C (176 - 194° F). 2. Stir the water and sift the HPMC. Continue stirring until the product is thoroughly mixed. 3. Add remaining water to a temperature of 5°C (41 ° F). 4. Continue stirring the solution for 30 minutes, or until the solution is smooth and free of lumps.

Benecel ™ MC et HPMC Product family Benecel Types A = Méthylcellulose (MC) Benecel Types E, F et K = Hydroxy Propyl MéthylCellulose (HPMC)

TYPE A4C A4M A15 A15C E3 E4M E5 E6 E10M E15 E50 F4M C F50 F50 R K4M K35M K99 C K100 LV K100M K200M

VISCOSITY, 2% AQUEOUS SOLUTION, MPAS AT 20 °C 320 – 480 2.700 – 5.040 12 – 18 1.312 – 2.450 2.4 – 3.6 2,700 – 5,040 4–6 4.8 – 7.2 7.500 – 14.000 12 – 18 40 – 60 2.700 – 5.040 40 – 60 40 – 60 2.700 – 5.040 26.250 – 49.000 80 – 120 80 – 120 75.000 – 140.000 150.000 – 280.000

TEMPERATURE °C OF GELLING IN 2% WATER

48 – 56 56 – 64 48 - 56 56 - 64 ~58 ~58 ~58 ~58 ~58 ~58 ~58 59 – 67 59 – 67 59 – 67 75 – 85 75 – 85 73 – 81 73 – 81 75 – 85 75 – 85

CONTENT IN% CONTENT IN % OF MC OF - HPMC MéthylCellulose

27.5 – 31.5 % 27.5 – 31.5 % 27.5 – 31.5 % 27.5 – 31.5 % 28 - 30 % 28 - 30 % 28 - 30 % 28 - 30 % 28 – 30 % 28 - 30 % 28 - 30 % 19 – 30 % 19 – 30 % 19 – 30 % 20.0 – 24.0 % 20.0 – 24.0 % 20.0 – 24.0 % 20.0 – 24.0 % 20.0 – 24.0 % 20.0 – 24.0 %

Hydroxy Propyl MéthylCellulose

GRANULOMETRY LASER IN ΜM MICROMETERS

170 min – 250 max 170 min – 250 max <295 170 min – 250 max

7.0 – 12.0 % 7.0 – 12.0 % 7.0 – 12.0 % 7.0 – 12.0 % 7.0 – 12.0 % 7.0 – 12.0 % 7.0 – 12.0 % 3.0 – 12.0 % 3.0 – 12.0 % 3.0 – 12.0 % 7.0 – 12.0 % 7.0 – 12.0 % 7.0 – 12.0 % 7.0 – 12.0 % 7.0 – 12.0 % 7.0 – 12.0 %

<234 170 min – 250 max <234 <234 <295 <234 170 min – 250 max 250 min – 450 max 170 min – 250 max <295 170 min – 250 max 170 min – 250 max 250 min – 450 max 170 min – 250 max 170 min – 250 max 170 min – 250 max


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SYNTHETIC BINDERS AND EMULSIFIER Dispersion by dry mixing of Benecel

This mixing process involves the combination of high purity, water-soluble Benecel HP ™ non-ionic cellulose ethers with other dry powders before adding water. The Benecel HPMC particles are separated by the addition of the other dry powders. This separation allows complete hydration when water is finally added.

Steps of dry mix dispersion

1. Mix and homogenize Benecel HPMC dry with all other powdered ingredients. 2. Add the combined powders to the total amount of water when stirred. 3. Continue stirring until Benecel HPMC is completely dissolved in water and the solution is free of lumps.

METHOCEL ™ A4M

Cellulose ether products Methocel ™ are carbohydrate polymers that dissolve in cold water and sometimes in some organic solvents by hydration and swelling. There is no solubility limit. The concentration of METHOCEL ™ in solution is generally limited by the viscosity which can be used. It also depends on the viscosity and the chemical type of METHOCEL ™ used. Methocel A4M is in the form of white powder to slightly off-white and gives matt films when dry and they are totally reversible. Methocel A4M has been used successfully for the consolidation of paint and wood. Methocel A4M dissolved can be brushed, sprayed or injected. Methocel A4M does not change the shades of the treated surface and can itself be tinted with pigments to make gouaches or other aqueous paints. Low viscosity solutions can be made in concentrations of 10% to 15%, while high viscosity products have a normal concentration limit of 2% to 3%. Viscosity at 2% in water (20 ° C) from 3,500 Min to 5,600 MPa Max. Particle size ~ 425 μm. Suitable for making satin and matt aqueous paint, but does not allow to make brilliant paints.

ÉMULSIFIER MARLIPAL©

It is a polyethylene glycol ether of non-ionic ethoxylated C16-18 fatty alcohol which acts as an emulsifier and improves consistency by reducing the surface tension of the materials to be emulsified. This ethoxylate alcohol appears as a solid and can be used with emulsified paints, it is generally used in a concentration of 0.1 to 2%. It is miscible with water in each ratio. However, very viscous gel phases can be formulated at concentrations greater than 25%, but are difficult to stir and to use. The stability of the aqueous solutions is very good. Marlipal has a lifetime of about 12 months, however in well filled and capped bottles, it can be extended. Solidification point 45 - 49 ° C

Marlipal® in granules and 18 g with 60 g of water

KLUCEL ® EF, G, HF et M

Hydroxypropyl cellulose (HPC). It is a nonionic cellulose ether which is both soluble in water and polar organic solvents, with remarkable qualities due to its solubility both in water below 38°C, insoluble above 45°C and in a large number of polar organic solvents such as ethyl, methyl or isopropyl alcohols, in water/acetone mixtures 1:9 but insoluble in toluene, xylene and trichlorethylene. Klucel® is compatible with natural gums, starches, acrylic and vinyl emulsions. It is reversible in water, even after drying. It is a very flexible ester, even without plasticizer. It is naturally non-perishable in the form of powder, it can therefore be kept for a very long time. The films he produces are slightly dull and do not become sticky even under strong humidity. I personally use Klucel replacing natural gums in my works of large format on canvas and to fix the lines pencils and charcoal before painting my oil. See fixatives.


SYNTHETIC BINDERS AND THICKENERS CHARACTERISTICS OF DIFFERENT KLUCELS TYPE

Viscosité Millipascal Second

Fluidity of the

Soluble in...

binder

Klucel® E

Klucel® G

7 mPas

300 mPas

Not very Water ethanol thick

acetone

medium

Cold water and polar solvents

Klucel® M

5000 mPas

thick

Cold water and polar solvents

Klucel® H

30000 mPas

very

Cold water and

thick

polar solvents

Klucel is useful for sizing waterborne substrates or in organic solvents, as pastel fixatives (0.5%) in a 9: 1 ethanol / water mixture, and for refixing paints and wood. Binders with Klucel® do not mold, but smell with time, so add a preservative like camphor. Refractive index: 1.337

similar to natural gum solutions but have a higher viscosity than water-soluble cellulose derivatives compared to other acrylic thickeners. The solutions can be used quickly since neutralization occurs instantaneously with standard bases. It is possible to use ASE-60 directly in the material to be thickened without pre-neutralization. If the binder contains sufficient alkalinity, it will neutralize ASE-60 and thickening will occur. If the binder is acidic then a pH corrector such as Ethomeen must be added to neutralize the acidity. ASE-60 solutions effectively bind pigments and other solids such as finely divided fillers, are also compatible with soaps, synthetic detergents and other dispersing agents. Polyvalent cations such as copper, aluminum or iron can disturb and corrupt ASE-60 solutions. At high concentrations, these cations can precipitate the polymer. Always correct the pH of the solutions before mixing with the binders and / or pigments. I mainly use ASE to thicken my acrylic paints made with Plextols®. Density : 1.00-1.20. Softening temperature: 0 ° (H2O). Boiling temperature: 100 ° C (H2O). PH: from 2.1 to 3.5. Viscosity : 100 mPas maximum.

ROHAGIT ® SD 15

Klucel® EF in aqueous solution

COAGULATING AGENT ASE 60

Thickener of acrylic and vinyl resins in polar phase. It is in the form of a milky white liquid. When the emulsion is diluted with water and neutralized with a base, each emulsion particle swells considerably. The emulsion becomes clearer under these conditions and becomes very viscous. Once neutralized, the ASE-60 solutions can not be converted into emulsions, since reducing the pH would precipitate the polymer. ASE-60 solutions have properties very

Rohagit SD 15 is a thickening agent based on an aqueous dispersion of a thermoplastic methacrylic ester copolymer of acrylic acid. It is a white liquid. It is used to create impastos and structural effects with acrylic binders. Rohagit SD 15 is a stable, universal thickening agent for polymer dispersions and other aqueous systems with a pH value of 8. Rohagit SD 15 salts are anionic polyelectrolytes. Its solutions are incompatible with cationic products. The viscosity of the aqueous solutions depends on the content of solids as well as on the type and amount of the base used for its neutralization. Its acidity can be neutralized with 1% to 25% ammonia. The consistency of its solutions is gelatinous, but not fibrous.

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SYNTHETIC BINDERS AND DISPERSANT MOWIOL®

Mowiol® consists of partially saponified polyvinyl alcohols (PVA) with different degrees of polymerization and hydrolysis. It comes in a white powder soluble in cold water only, it is very resistant to bacteria, and has good resistance to light.

It serves as an adhesive agent, as a fixative for the surface treatment of papers, as a dispersion modifier, as a paper adhesive, as a protective metal coating, as a sizing agent for textiles.

acid. It is a raw material for paints and coatings for exterior and interior. It is used to produce high-quality exterior paints and coatings on all kinds of stone walls, concrete, shade paints, resin-bound coatings and textured coatings, plasters for marble, Insulation of exterior walls. The DM 771 dispersion can also be used for bonding and ceramic tile adhesives, as well as mastics particularly suitable for applications with high requirements for water resistance and alkali resistance. The DM771 ​​has a high resistance to yellowing and excellent UV resistance, and is compatible with cement. The DM 771 acrylic dispersion must be agitated homogeneously before use. Add a preservative to the binder. PH 8 - 9 (ISO 976) - Solid content: 49-51% (ISO 3251) - Viscosity at 25°C = 8000 to 15000 mPas.

3 g polyvinyl acetate + 6 g of water + 6 g of glycerin

OROTAN 731 K DISPERSANT AGENT

Orotan is a pale yellow liquid. It is a polyelectrolyte sodium carboxylate salt which is added to synthetic paints in order to disperse the pigments which have difficulty mixing with the binder. In addition, when mixed with a high performance binder or other high quality additives, it can provide greater corrosion resistance to the formulations. Orotan 731 K is compatible with a wide range of pigments, diluents and polymers, is effective in a wide pH range, contains no ammonia and has excellent thermal stability. It is dilutable with water. It has a pH of 9.5 to 10.5 and a viscosity of 55 to 185 mPas. orotan 731 K 100 ml

ACRYLIC DISPERSION DM 771 OU MOWILITH 771 The acrylic dispersion DM 771 is an aqueous dispersion of copolymer based on acrylic acid and methacrylic

MODIFY THE VISCOSITY OF ACRYLIC BINDERS The viscosity of the acrylic resins may be increased using either of the following two techniques or a combination of the two.1. By addition of ammonium hydroxide NH4OH, triethylamine N(CH2CH3)3 or any other volatile amine C6H15N, the system can be thickened.Check the pH before and during the addition.2. Water miscible alcohols such as tert-butanol (CH 3) 3 C-OH, isopropyl alcohol CH3CH(OH)-CH3 or ethanol C 2 H 6 O may also be added to increase the viscosity of the binders. NOTA BENE These adjuvants as well as all pH adjusters should be added in small amounts at a time, with dropper and constant stirring (with a mixer is better) to avoid lumps forming, otherwise it corrupt the acrylic binder (basic or acidic pH following the resin), it becomes like curdled milk. VERY IMPORTANT THE ACRYLIC BINDERS MUST BE FRESH, THAT IS TO SAY WITHIN THE EXPIRATION LIMIT OTHERWISE THE FILMS SHOW POOR AGING QUALITY.


OLEAGINOUS BINDERS The Iodine number of oils

The Iodine lipids is the mass in grams of diiodine (I2) capable of binding to the double bonds of fatty acids contained in 100 grams of fat. The higher the number, the more the oil contains unsaturated molecules (the more double bonds C = C), the more likely the oil will reticulate in air. Oil is said to be drying if the iodine number is greater than 150, semi-drying if it is between 110 and 150 and non-drying if the index is less than 110. See Glossary

Walnut oil

She is extracted from the ripe walnut fruit the Juglans regia L., which contains a dye in a free state or in the form of glucoside (a heteroside compound, consisting of sugar and other substances, of which A glucose): hydro-juglone, C10H6O3 consisting of tannin. The juglone is in Color Index NBr7 75500. Therefore when preparing the oil, it is necessary to remove the pericarp of the fruit if not the oil will be very colorful. The walnut oil is taken from the almonds perfectly hulled and consists of removing the thin brown skin that covers them. The shells contain in their hearts nuts, the oil content of which is about 50 to 65%. It takes about 3 to 15 years for a walnut to bear fruit for the first time with a fungicidal and natural disinfectant effect. Three months after picking (from September to November), it is found in commerce under two distinct qualities: The first, known as virgin oil, is extracted by cold pressing, it serves mainly for consumption. The cakes, the residues of this first pressure, are then diluted in boiling water, and passed to a second pressure, which extracts a oil of a greenish tint, somewhat caustic and more drying than the first. This quality of walnut oil is called "firing", it is used in industry, in painting for the manufacture of soaps and varnishes (suppliers 15). If you want to make homemade walnut oil, grind the fruits very carefully, place them in a sieve over a saucepan of boiling water, when the cakes have softened, to the point of being able to make it a paste : squeeze this paste through a large piece of fine cotton cloth. It is necessary to have a fruit press, the kind to make wine and that develops enough strength to make oil. The nut oil rancid rapidly in the air and becomes lighter, this property is used for the preparation of fine colors and can also have its advantage for the making of certain varnishes, if you want an oil very little colored . The walnut oil thickened by cold and becomes already very viscous at -13 ° C, to solidify completely in a white mass at -27.5 ° C. It has a density between 0.926 and 0.928, it thickens between -15 ° C and -18 ° C. Submitted to the action of the nitrous fumes, it gives a liquid mass. The absolute sulfuric saponification is 99 ° C., the relative is 275 ° C. Iodine value between 135 and 160, for bromine 737, for acetyl 7.3. Its fatty acids are fluid at ordinary temperatures, their densities are 0.912 to 15 ° C. It does not deviate

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from the plane of polarization. Walnut oil is falsified by adding other oils such as cottonseed oil, poppyseed oil, sesame oil or peanut oil. When she is pure, the sulfuric acid test gives a brown color, the precipitated lead test gives an oxygen absorption of between 7.5 and 8.5%. Siccativated walnut oil is the best of all oils, it has been so discrediting, that we have almost relegated her as unsuitable oil for painting, one more thing due to the loss of the painter's craft, we reproach her from going rancid, so be it. Its a qualiWalnut oil ty in her case and this is an exception. The rancidity problem of walnut oil has been solved by its alkali refinement which reduces its amount of free fatty acids. However, I advise you to buy pure oils from suppliers who buy from artisans who make their own oils. I have always been buying very good quality walnut oils from and L'Olivier, 23 Rue de Rivoli 75004 Paris, then I prepare them for oil painting. Personally, I mainly use walnut oil for my paintings and I have noticed that this oil allows an hardening to heart that the other oils does not possess. On the other hand siccativated, it hardens very quickly (I insist on the term of hardening, the word drying is to be reserved for aqueous binders), thus making it possible to complete a painting in a very short time, sometimes and according to the pigments used In about ten days. From Vasari to A.-P. Laurie, Turquet de Mayerne and Watin to Jacques Maroger and Claude Yvel [36] closest to us, all mention the superiority of walnut oil on all other drying oils. Of course, Walnut oil from only connoisseurs praise it and rightly so. Without walnut oil, many of the finest paintings in museums would not exist. Ideally, the oil should be left to stand for at least 2 years before using her, she reaches her optimum stability only after increasing in volume the first two years, which has the positive effect of seeing it to clarify at the end of this period (Jean François Léonor Mérimée 1757-1836). "The older the walnut oil, the better it is."[16]


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OLEAGINOUS BINDERS Linseed oil or Flax oil

Flaxseed oil is produced with the mature seeds of cultivated flax of Linum usitatissimum L. The almond is covered by a kernel which is abundantly charged with an oil-soluble yellow coloring matter, which strongly colors the oil. However, we can try to clarify the oil by exposure to the sun, but it will turn yellow again if we keep the paintings in the dark. Another half-truth about the exposure to the sun of painted pictures, because, after drying, the yellowing will settle irrevocably, unless using oils already cleared by UVA rays.

CHEMICAL ANALYSIS Total Fatty acids C 4: 0 Butyric acid C 6: 0 Caproic acid C 8: 0 n-Caprylic acid C 10: 0 Capric acid C 12: 0 Lauric acid C 14: 0 Myristic acid C 14: 1 Myristoleic acid C 16: 0 Palmitic acid C 16: 1 acid Palmitoleic C 18: 0 stearic acid C 18: 1 Oleic Acid C 18: 1 Isometric C 18: 2 Linoleic acid C 18: 3 Gamma Linolenic acid C 18: 3 alpha linolenic acid C 20: 0 Arachidic Acid C 22: 0 Behenic acid C 22: 1 Erucic acid

% < 0.1 < 0.1 < 0.1 < 0.1 < 0.1 < 0.1 < 0.1 5.4 0.1 3.8 3.1 0.6 17.7 < 0.1 58.4 0.1 0.1 <0.1

Poppy oil Flaxseed or Linseed by BERTFR via Wikipedia

If yellowing is a factor that disturbs you, you have to paint with other non-yellowing techniques like "Cera Colla" (a good alternative to oil painting), a very pleasant technique to use when mastered. Flaxseed oil is a highly viscous oil, she is the yellowest of the oils while the poppy oil is the clearest once clarified.

This oil extracted from Papaver Somniferun L. with oil seeds gives poppy oil. She is a variety of somniferous poppies, cultivated for its seeds, from which it is derived from the orient. The poppy also contains a white latex in its capsules, but it is the seeds that gives the oil. Oil of poppy was obviously used in the Middle Ages.Turquet de Mayerne describes her use by artists of the seventeenth century. This oil has been sought extensively and used by the artists of the nineteenth century, as it yellows less than other oils. However, due to its poor siccativity, it makes a poor oil to grind pigments for paints if not siccativated. Iodine number: 133-158. Saponification number: 189-197

CHARACTERISTIC OF A MODERN LINSEED OIL ACCEPTABLE COMPOSITION OF A LINSEED OIL IN%

Saturated acids min: 8 max: 11 Oleic acid min: 14 max: 15 Linoleic acid min: 20 max: 25 Linolenic acid min: 48 max: 58

I personally made little use of this oil, I prefer walnut oil. Linseed oil contains fatty acids constituting the triglycerides (glycerols) main elements of vegetable oils. Flaxseed protects from the UV the objects it surrounds.Iodine value of linseed oil: 170-190

Poppy seed

Poppy oil

Cooked with litharge like black oil or mixed half with walnut oil and cooked, the blend of these 2 oils "poppy and walnut", becomes an oleaginous binder of very high-quality. I call this mixture of cooked oils "Clear oil".


OLEAGINOUS BINDERS Grape Seed Oil

She requires nearly 100 kg of grape seed to obtain 1 liter of oil. Grape seed oil is known for her resistance to high temperatures. Rich in polyunsaturated fatty acids, she contains virtually no alpha linolenic acid. She is extracted by first cold pressing. She is soluble by cold in absolute alcohol and by hot in 90°C alcohol. It contains 85 to 90% glycerides of unsaturated acids (oleic and linoleic acids) and also contains those of stearic and palmitic acid. She is a study quality oil , she is semi-drying however cooked with litharge she allows an hardening to heart. 25 years ago, I painted a few paintings with this oil and they are in good condition. She solidifies at -15°C. her density is from 0.920 to 0.940. Saponification index is 180 to 196. Iodine number 124-143

Ricin seed oil also know as Castor oil

Taken from the Ricinus communis plant native from northeastern Africa and the Middle East. The Egyptians cultivated it and used it at least to light up 6000 years ago. The most important sources of castor seeds are found in East India, Java, Mediterranean countries, Mexico and the United States. Castor oil comes from a euphorbiacea. She is a mixture of fatty acids glycerides, the main one being ricinoleic acid. The leaves contain an alkaloid, the ricinine, which can cause severe poisoning. The seeds are rich in oil and protein : 46 to 53% of oil and 15 to 20% of protein and contain a very dangerous toxalbumin call ricin. Castor oil is highly dextrorotatory. The crude castor oil is refined by steam, so that the proteinaceous materials are coagulated, in order to be removed by filtration. The seeds are crushed and this more or less homogeneous paste is heated and placed on a sieve which allows the oil to drain. This castor oil in its modern version serves as a plasticizer in some oil or alcohol varnishes, she makes them less brittle. Castor oil She is the oil with the highest density : 0.962. She has a refractive Index at 20°C. of 1.479. Viscosity : 997 mPas. Iodine value : 82-90. In thin layers this oil does not harden even when exposed to air. She is entirely soluble in alcohol, a pro-

perty which has long been used, since it does not tint the varnish in which she is mixed. she can be used in a small part (0.1%) in varnishes for plasticizing. There is also a castor stand-oil which hardens very slowly.

China Wood or Tung Oil Also called Abrasine Oil

Taken from the walnut of aleurites, it is used to make printing inks. The aleurites are the genus Aleurites of the Euphorbiaceae family : the bancoulier which has the Latin name, Aleurites moluccana, the Chinese wood of Japan, but it is also extracted from the seeds of the nut of the Chinese tree, Tung. Aleurite is a tropical tree of the Euphorbiaceae family, native to the Far East and many islands of the Pacific, cultivated in Europe and in the United States. Another species, also known as Chinese wood, originating from Central Asia, is also cultivated in the southern United States and reaches in height 7 m. Tung oil is composed of stearic acids (eleostearic acid) and less oleic, linoTung Oil leic and palmitic glyceride. Eleostearic acid is an unsaturated, crystalline fatty acid that exists in 2 isomeric stereo forms, an alpha acid that occurs primarily as the ester of glycerol in Tung oil and a beta acid obtained from alpha acid by irradiation (Octadecatrienoic acid : 9-11-13). The following chemical formula shows the structure of the eleostearic acids of the Tung oil : CH3(CH2)3CH=CHCH=CHCH=CH(CH2)7COOH. Its seeds are roasted, powdered and pressed to give a dark brown raw oil, called dark wood oil. The so-called white wood oil, actually pale yellow, is obtained by pressing the unroasted seeds. Used in paints and varnishes as a very powerful drying agent, it also serves to waterproof paper and various types of ceramics and to feed timber. Density at 20°C from 0.930 to 0.939. Refractive index from 1.513 to 1.522. Acidity ~ 5. Iodine number from 205 to 215. Saponification number: 189 to 198. I tested this oil in 2018, it serves as a reinforcement for other oils as a natural accelerator hardening. By mixing 30% of walnut oil, it gives a beautiful shine to oil paintings for glazing.

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OLEAGINOUS BINDERS STAND-OIL OR POLYMERIZED LINSEED OIL

The polymerized linseed oil is obtained by a particular method for substantially reducing the volume of unsaturated fatty acids in linseed oil and increase stability and reduce its tendency to yellow. The oil obtained by this method of purification was known in Holland, from the fifteenth century, and was called stand-oil. It was prepared in the past by a laborious process consisting in heating it up to 350 ° C, whereas it is now produced industrially, by heating it under vacuum or in an inert atmosphere. The polymerized oil is less colored, very stable,And its hardening is very slow.I use it in lacquered type paints call "Chinese lacquer" and for varnishes that I want very viscous. Viscosity: 450 mPas.

polymerized castor oil

SAFFLOWER OIL

Linen stand oil

Good quality safflower seeds weighing 19-21 kg per bushel contain 22-28% oil. Extensive oilbased laboratory tests, followed by manufacturing plant tests, indicate that it is a valuable raw material for use in paints, varnishes and related industries. Safflower oil has good hardening and paints made with this oil are durable and Carthamus tinctorius weather resistant. It has been found that it is much less yellowing and its color is rather clear, both in white paints and in enamels. Varnishes made with safflower oil behave normally, they possess a shine and optimum strength. The oil lends itself satisfactorily to heat treatment, refining and bleaching. The oil can be heated for 2 hours at a temperature between 307°C. and 310°C. and she polymerizes into a rigid but highly elastic mass which is soluble in turpentine and other nonpolar solvents. Safflower oil is also a product that can be useful as a base for the manufacture of linoleum. Many manufacturers report the use of safflower oil in the manufacture of paints and varnishes favorably. It is particularly useful in the manufacture of paints

Safflower oil is extracted from the seeds of an oleaginous herbaceous plant called Safflower of the dyers: Carthamus tinctorius L., of the Asteraceae family. It was cultivated in India and Egypt for many years as an oilseed crop and as a source of red dye obtained from flowers.There are two distinct varieties of plants, ie, typicus and inermis. The first is thorny and the second without thorns.Plants that are very thorny in the wild show a tendency to become thornless in culture. The spiny variety is considered the best variety for oil production. In the industry of paints, varnishes, linoleums and related products large quantities of drying oils are needed. Until now it was linseed oil which was preferred, but in view of the increasing quantities needed by industry, linseed oil was no longer sufficient. The culture of safflower was implemented in 1930 [67], to come to the help of a linseed oil production which was beginning to lose steam in favor to the growing mode of the cotton fiber. [65] Carthamus tinctorius By Daderot via Wikimedia


OLEAGINOUS BINDERS and white enamels, where a permanent whiteness is desired.Safflower oil-based paints have satisfactory durability and weather resistance. The characteristics of safflower oil depend highly on its fatty acid composition. Oleic acid (C18: 1 A9) and linoleic acid (C18: 2 A9,12) are the two main fatty acids present in safflower seed oil, together accounting for about 90% of the total fatty acids . [66] Conventional safflower oil is characterized by its relatively high content of linoleic acid, about 74.6% compared to most other seeds oils.[65] Oleic acid has a greater oxidation stability compared to linoleic acid because it contains one less double bond. The purified oleic acid is also a valuable chemical raw material, and may undergo cleavage to form derivatives such as azelaic acid which can be used in the formulation of a range of industrial products and polymers ; as a result, safflower oil has an important place in modern industry of building paints.[68] It is the oil that contains the most linoleic acid (polyunsaturated) with about 74.6%. Some manufacturers of artistic paints use it to grind whites, blues and some other light colors. It is used in industrial paints because it has the reputation of less yellowing. It is a common ingredient in paints of alkyd resins and she is used industrially in large quantities. COMPOSITION OF SAFFLOWER OIL ON 100 G

Palmitic acid (saturated)

4,288 g

Stearic acid (saturated)

1,915 g

Oleic acid ω-9 (Mono-unsaturated)

14,35 g

Linoleic acid ω-6 (Poly-unsaturated)

74,64 g

Trans fatty acids

-

Total Saturated Fat

6,203 g

Total mono-unsaturated fatty acids Total acids Poly-unsaturated fatty acids

14,35 g 74,646 g

Vitamine E

34,1 mg

Vitamine K

7,1 µg

Index Iodine 130-150 Refractive index - 1.476 to 1.4810. This oil is generally considered to be inferior to linseed oil in terms of its long-term durability and there is a significant risk that the paint films will become brittle over time. If you decide to use it anyway, to plasticize it, add to it a little Venetian medium, castor oil or some other oil. This vegetable oil can be clarified and siccated, it is

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low acid, characterized by low yellowing and excellent compatibility with pigments. Due to its pale color, it is recommended for grinding whites and light tones. It can be mixed with oil colors to accentuate their fluidity and brilliance without altering the shade during the Hardening. It is much less drying than linseed oil, but can be safely mixed with it.This oil is less yellowing than linseed oil, but it also has some disadvantages: Its hardening time is longer and the oil forms a film with properties other than those of linseed oil. As a result of its other properties, the use of safflower oil paint in a technique that is made up of various layers (where it forms an undercoat for linseed oil paints) can cause the cracking or even the detachment of the latter and even an inability to adhere properly to the supports. Refined safflower oil

His use into the artistic field is recent, moreover we do not have much studies on its stability. I have searched on the Internet and in the literature for technical data on this oil, but apart from some generalities, nothing conclusive at the end can be retained on the intrinsic qualities of this safflower oil. However, cooked in the presence of drying agents, this oil could be a binder having excellent film-forming qualities, if cooked without exceeding 95°C for 2 hours maximum, to preserve its character of clear oil. This oil is unfortunately difficult to find in liter and ever more and it is not sold among the most important suppliers! The future will tell us if we were right to use this oil. Safflower oil from the Moulin de Montoison 2017


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PAINTS WITH OLEAGINOUS BINDERS

Hitchcock. Paint with egg yolk and pigments on Wood 47 X 40 cm. Blue is azurite, red Pozzuoli oxide and yellow of naples ©1994 David damour

Incognito. Oil painting and tüsclein on wood MDF 65 X 50 cm. Cochineal, gall and spinel black. ©1997 David damour

Oil paints that I grinded and put in tubes 2017 I have not touched them yet I will use them for the book N°5


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SICCATIVES Driers are substances that are added to the oleaginous binders to accelerate the hardening of paint films. These materials should rather added to the oils or binders, no on the palette, whether in the form of powder or point fluids, because of the accuracy of the dosages. Siccatives are present in virtually all conventional lacquers as well as in the oily products of natural paints, they are found even in water glazes. These are solutions composed of metal salts and organic solvents. The metal salts catalytically accelerate the hardening of natural drying oils. A linseed or walnut oil non-siccatives hardens in a 3 to 7 days interval, while the same drying oil will harden in a day. The cobalt and manganese salts cause rapid surface hardening. The zirconium, calcium and zinc salts allow for the regular hardening of the oily film. Lead, despite its toxicity and the fact that non-toxic equivalent products have been found, is still used in many conventional lacquers. As a rule, lead is not used in ecological paints. Recently, cobalt has been the subject of the same suspicions as lead: it is the dust caused by the sanding of old paints containing cobalt siccatives that penetrate the body through the respiratory tract. We have the same problem with the fine dust generated by the sanding of untreated wood. It is essential to guard against the dangerous effects of such substances by means of adequate dust protection, ie a mask. In addition, in conjunction with an oily product, cobalt does not pose any danger to humans. This is why it is allowed as a siccative, for example in surface treatments with linseed oil of wooden toys (European safety standard for toys). However, it is necessary to consider the appropriateness of the use of hazardous products in natural paints.

Massicot

There are however accept a compromise, despite the research, there is no currently of equivalent to the driers of cobalt product. The drying speed up hardening of the paint films. Note the use of the word "harden" and no "dry" that applies to aqueous binders. They are the catalysts of the oxydo polymerization of drying oils and alkyd resins that are introduced at rates between 0.5 and 4% by weight in oils or printing inks. Dryiers consist generally of metal salts of fatty acids (typically of linoleic acid) soluble in oil. Regardless of the nature of the solvent and the nature of the ligands (or anions), which lie on the metal cation. Metals that can be use as drying are cobalt, lead, manganese, iron, nickel, bismuth, cerium, titanium, calcium, barium, zinc, lithium, zirconium, vanadium, copper and strontium.

The Litharge

It is a lead oxide of Chemical Formula: PbOResulting from the oxidation of the metal heated in air and according to its Litharge or Massicot state, one has undergone a fusion and the other not. It is the best siccative for artists oils, it comes in the form of yellowish or orange powder. In my opinion this is the most desirable siccative, however it must be preceded by extreme precaution of use; In its pulverulent form, once incorporated into the oil, the risk is minimized : wear glove and mask. I have been using this product for over 30 years without worry, because I observe draconian measures. For professionals, this product is, and will always remain the best siccative despite what its detractors think.

Litharge


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SICCATIVES The Massicot

It is lead oxide, yellow if cooling was fast, it has a redOrange tint if cooling has been slow. Color Index PY 46.77577 Chemical Formula: PbO Refractive index: 2.60 As a pigment, it is obsolete since the late eighteenth, early nineteenth century. The word Massicot comes from the Italian "Marsacotto" which contains the word "cook", we find traces of its use in the book "I tre libri dell'arte del vasajo" the art of the potter by Cipriano di Michele Piccolpasso. Lead oxide was known by the Egyptians from the predynastic period, through the metallurgy of lead, and was known by Greeks and Romans. A.P. Laurie pointed out a yellow lead oxide on the "scribe's palette" dated 5 centuries before Christ.

the thickness of the film, it is then called siccative to heart like lead driers. These driers are added to the paints in quantities generally less than 2.5%. There is also manganese octoate. Harmful Substances. Manganese acetate Tetrahydrated

The Cobalt

Cobalt salts tend to start the hardening reactions (They promote the formation of hydroperoxides, by repeated transitions of cobalt from Co2 + to Co3 +).Cobalt and cobalt compounds are considered to be potentially carcinogenic to humans and highly toxic to aquatic animals. Cobalt siccatives are a substitute for lead. They are perfect for light colors. These lead free driers consist of cobalt octoate, an organic salt of cobalt and zirconium blended intimately with Chemical Formula : C16H30CoO4 Or cobalt (II) naphthenate added to the Cobalt octoate binders in amounts generally less than 2.5%.

Vanadium

Massicot put in a frying pan to cook the oils

Manganese

The manganese oxide derived from the mineral called pyrolusite advantageously replaces cobalt dryers, however they are dark. Manganese acetate (an oxidation catalyst) or manganese naphthenate are mixed or fired with oils. Chemical Formula Mn(C11H7O2) which has a melting point at 150°C. The liquids are then allowed to settle, so very dry oils are obtained. The manganese acetate tetra hydrated of Chemical Formula: Mn (C2H3O2) 2.4H2O, is present in the form of pale pink crystals. It is soluble in water, ethyl alcohol and methyl alcohol. Manganese, for its part, has a more uniform action in

Particular derivatives of vanadium are used as siccative for hardening paints by oxidation. These dryers are ionogenic in nature and contain polyvalent cations of vanadium or vanaCobalt Acetate II Tetrahydrate dium oxide and radicals of anionic organic acids or other organic anions. These driers are ionogenic metallic derivatives which are added to unsaturated oils and binders (the constituents of paints who harden by oxidation). This conversion results from an oxidative crosslinking which is accelerated by the metal cations or cation oxides of the ionic metallic derivative of vanadium. The vanadium derivatives, in particular vanadium pentoxide and vanadium linoleate, are used as accelerators for hardening oils by autoxidation, also vanadyl di-carboxyVanadium oxide (V) lates, vanadyl acetate, vanadyl ethylhexanoate, vanadyl oxalate and vanadyl malonate. The compounds of general formula are


SICCATIVES used in the form of a solution in water or in oil in an acid environment (at pH less than 5), so we can appreciate particularly solutions of vanadyl derivatives of general formula with pH of 0 to 3 by phosphoric acid, hydrochloric acid, sulfuric acid or their acid salts. The use of vanadium as siccatives requires very precise formulations that are not within everyone's reach.

Zirconium

The present zirconium siccatives are prepared with combined zirconium and calcium octoate, ethylhexanoic acid, a zirconium salt or zirconium carboxylates. They act in depth and on the surface. They accelerate the crosslinking and allow a balanced hardening of the thick layers. Very powerful, they must be carefully controlled. Colorless, they do not contribute any alteration to light colors and are very effective for blacks and lacquers. In trade, it is called courtray drier, but I strongly advise against using them on the palette. Instead, get zirconium octoate and incorporate it into your pure binders. I repeat, because it is very important, that any siccative must never be added on the palette, in the paint pastes, but in oils or any other liquid binder aczirconium octoate cording to your choice. Because of the precision of the dosage, the quantity of siccative can be dosed more finely on a liter than on a nut of paint on a pallet. The zirconium and calcium "Coutray" siccative that we found in trade is a very good siccative, otherwise one of the best, because it avoids accidents of overdosing (dixit some suppliers). It's a fashionable siccative at the moment (2016).

Calcium keeps the paint film matrix open, which prevents the solvent from dispersing or escaping at the beginning of the hardening process. Calcium allows dispersion of the pigment and reduces the lack of siccativity when added to the pigment grinding step.

Copper

We use copper as an oxidation catalyst since at least the seventeenth century, at the Velasquez's time, a Spanish oil cooked with copper was used by the masters. It is an oil cooked in the presence of copper, which has been macerated in vinegar for at least 15 days. This very fine oil was very sought after. I made this oil and it is true that she is very beautiful, however it should be reserved for the blue and green colours, because it has a greenish tone, very light, but very subtle. copper octoate It hardens walnut oils by oxidation. As lead its a siccative very complementary to the others, it has to be reserved copper acetate however to the connoisseur, because copper is toxic. Today, the most commonly copper used as siccative is copper ethylhexanoate (copper octoate), a greenish blue liquid that contains 6.0% to 12.0% copper. It is also possible to use copper acetate.

Cerium

More reactive than lead, effective even at low temperature and high humidity. Cerium can cause a yellowing of the film of dry paint and an excess can cause a skin effect on the surface of the paints. Pure cerium is often too expensive to formulate paints. For a lower cost, a mixture of rare earth metals is commonly used with the same benefits. Cerium can be considered as a primary siccative, i.e, a small part of it is added to the formulations of some systems. cerium carbonate

Strontium

Calcium

calcium octoate

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Its a siccative to heart (like lead, lithium, zirconium and strontium) wich connect the fatty acid chains with oxygen/metal/oxygen bridges leading to crosslinking. Currently used as a replacement for zirconium and lead. It is not known to be toxic such as zirconium and lead, because strontium compounds are insoluble in aqueous binders. It is a siccative of the future, which should be studied for Strontium hydroxide Octahydrate use in place of other toxic siccatives.


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SICCATIVES Organic Siccatives

The two most commonly used products in this role are first : 1,10-phenanthroline, which is an organic compound of the formula C12H8N2, formed of three aromatic cycles adopting the arrangement of phenanthrene and 2) 2,2'-bipyridyl, a chemical compound of formula NC6H4-C6H4N, which is in the form of a crystalline white solid, combustible and slightly soluble in water. It belongs to the bipyridine family of formula (C5H4N) 2, of which it is an important isomer. These two products are aromatic amines with high toxicity. Non-amine aromatics and amine derivatives are now more commonly used because they have a lower toxicity, but they also have a lower reactivity compared to aromatic amines. The function of the ligands with the metal increases the activity of the latter and leads to the decomposition of the peroxides and thus reduces the hardening time. The main advantages of using amines in consideration of their effectiveness are : 1. The type of resin 2. Temperature 3. The chemical nature of the amine These dryers are used to provide advantages for the complete spectrum of alkyd resins and alkyd emulsion systems.

Elaboration of siccatives

Caution

The odor emitted by solvents such as aspic essence, turpentine and lead paints can be inconvenient in the long run. You must let harden the paints made, in another room than the place where you live. Wear gloves and use a barrier cream when handling your tubes. Personally I am a great asthmatic and I am allergic to a lot of materials, but these paintings never bothered me, however it is true that you should avoid painting too near with your nose on a few inches of your canvas. The toxic pigments are much more virulent, I happened to have a discomfort because of the cinnabar. Toxicity is the major problem of paints, but there are in particular many non-toxic techniques such as cera colla, enluminure, oil/water emulsions, encaustic, gouache, watercolor, etc. ...

Conclusion

I intend in the short term to realize and develop pictorial materials free of all toxic siccatives and toxic compounds, possessing the same characteristics as drying oils and mediums allowing to change their rheology. Mixtures of strontium and calcium could be the most promising. I will present the result of my research and the recipes in my next book "Gestures and Paints Materia", a less theoretical and practical book on painting, i.e with less recipes and more gestures. The painting's practice with all the materials andsubstances exposed in this book.

Making driers to standardized metal content and adequate solubility is achieved by means of three types of reactions : 1. Fusion of metal oxides with suitable organic acids - for example, lead oxide and 2-ethylhexanoic acid to give 2-ethylhexanoate of lead. 2. Double decomposition by the reaction of a solution of cobalt sulfate with sodium naphthenate in the presence of a solvent such as mineral spirits to give a solution of cobalt naphthenate solvent (the aqueous solution of sodium sulphate which is formed is separated from the solvent solution).

COPPER ACETATE

3. Direct melting of the metal, for example, metallic cobalt is reacted with an organic acid in the presence of air and water, giving soaps of cobalt of high purity. As a general rule, avoid adding more than 5% to 7% of dryers in the total volume of the binder.

Manganese nodules By WarXboT via Wikimedia Commons


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MOLECULAR REPRESENTATION RESINIC ACID STRUCTURES

ABIETIC ACID

PALUSTRIC ACID

LEVOPIMARIC ACID

PIMARIC ACID

NEOABIETIC ACID

DEHYDROABIETIC ACID

ISOPIMARIC ACID

SANDARACOPIMARIC ACID

Vector Illustration © 2016 David Damour


36

LIST OF BOILING POINT-MELTING POINT Turpentine

Boiling point: 149-180 ° C Flash point: 30 to 46 ° C Melting point: -50 to -60 ° C Relative density (water = 1): 0.86 to 0.9 Kg / l Autoignition temperature: 220 ° C

Aspic Essence

Boiling point: 183 ° C Density at 20 ° C from 0.880 to 0.930 Density: 0.893 g / ml at 25 ° C Refractive index: 1.47

de-aromatised Essence of Petroleum Boiling point 140 ° -160 ° C

Alcohols at 90 or 95°C

Boiling point: 56 - 53 ° C Relative density 0.819 (at 20 ° C)

Shellsol A

Boiling point 155-185 ° C

Shellsol® D40

Boiling point: 145-205 ° C Flash point> 38 ° C Density at 15 ° C, g / ml 0.760 to 0.795

Shellsol® D70

Boiling point: 190-250 ° C Flash point> 70 ° C Density at 15 ° C, g / ml 0.780 to 0.820

Shellsol® T

Boiling point: 185-215 ° C Flash point> 61 ° C ASTM D93 Density at 15 ° C, g / ml: 0.761 Refractive index = 1.4240 - 1.4310

Ethanol

Boiling point: 78.37 ° C Melting point: -114 ° C Density: 789,00 kg / m³ Molar mass: 46.06844 g / mol

Methanol

Boiling point: 64.7 ° C Melting point: -98 ° C Density: 791.80 kg / m³

Dammar Resins

Fusion point around 130 ° C Melting point: 87-100 ° C Density: 1.04 to 1.12 Autoignition temperature: 464 ° C

Xylene

Boiling point: 137-140 ° C

Toluene

Boiling point: 111 ° C

Mastic of chios

Softened at 90 ° C and melted at 105 ° C Melting point up to 120 ° C Density: between 1.04 and 1.07

Sandarac Resin

Softening at 100 ° C and melting at 135 ° C Density: 1.092

Shellac

Melting point between 77 ° and 82 ° C

Balsam of Canada

Boiling point: 43 ° C Flash point: 62 ° C (144 ° F) Flash Point in a vacuum: 50 ° C Density: 0.985 to 0.995 Rotatory power: + 1 ° to 4 ° Acid value: 84 to 87 Ester number: from 5 to 10

Balsam or Turpentine from Bordeaux Boiling point: 156 ° C Melting point: 130 ° C Specific weight: 0.856

Eastern Hemlock

Melting point 135 ° -136 ° C

Regalrez 1094

Softening point of 94 ° C Glass transition temperature: 33 ° C

MS2-A Resin

Softening temperature: 85 to 100 ° C Density: 1.08

Copal Resin

Melting point: 77 ° C to 82 ° C Boiling point: 320 ° C

Baltic Amber or Succin Melting point: 295-395 ° C

Paraloid B 72

Melting point: 145-150 ° C Density: from 39.8 to 52 Begins to melt around 70 -75 ° C


37

LIST OF BOILING POINT-MELTING POINT Camphor

Spermaceti wax

Melting point: 175 ° C Boiling point: 204 ° C Density: 0.992 at 10 ° C

Between 45 to 50 ° C

Ouricuri wax

Between 79 and 84 ° C

Mowilith 20®

Softening point: 80 - 100 ° C Glass transition temperature: 30 - 40 ° C

Candelilla wax

Mowilith® 30

Lanolin or Suintine wax

Softening point of the film: 105-125 ° C Glass transition temperature (Tg): 30-40 ° C

Mowilith® 50

Softening point of the film: 140-160 ° C Glass transition temperature (Tg): 35-45 ° C Viscosity (20% in EE) at 20 ° C: 100-160 cps

Mowilith® 60

Softening point of the film: 160-180 ° C Viscosity (20% in EE) at 20 ° C: 180-250 cps Glass transition temperature (Tg): 35-45 ° C

Beeswax

Melting point: 60-65 ° C. Density: 0.9272 and 0.9697

Bottom between 68.5 and 70 ° C Between 38 and 42 ° C

Polyethylene Wax A Between 98-108 ° C

Zirconium

Melting point: 2200 ° C

Graphite or Plombagine

Very high melting point: 3500 ° C

Molybdenum Orange Melting point> 800 ° C Density: 5.30-6.10

Manganese

Melting point: 150 ° C

Carnauba wax

Melting point: 85-101 ° C

Order of Abundance of Primary Chemical Materials in the Earth's Crust Up to 30 km and whose content exceeds 10 grams per tonne. (from P. ARNAUD) Silicon Aluminum Iron Calcium Magnesium Sodium Potassium Titanium Hydrogen Phosphorus Manganese Fluorine Barium Strontium Sulfur

272 000 83 000 62 000 46 600 27 640 22 700 18 400 6 320 1 520 1 120 1 060 544 390 384 340

Carbon Zirconium Vanadium Chromium Nickel Zinc Cerium Neodymium Lanthanum Yttrium Cobalt Scandium Nitrogen Lithium Lead

180 162

136 122 99 76 66 40 35 31 29 25 19 18 13


38

ESSENCES AND SOLVENTS NOTA BENE All of these products are harmful to health from exposure, wear gloves and a mask, especially if you are using Toluene and Xylene. It is imperative to always read the technical data sheets of such substances before handling and using them. Remember that there are barrier hand creams to prevent allergies. ESSENCES - ALCOHOLS AND AROMATIC HYDROCARBONS

Formerly, essences were called "essential oils": they are organic compounds resulting from the distillation of natural substances, of which they constitute the volatile and odoriferous part. They are used to lengthen and temper paint pastes, but also to make various mediums and varnishes, to degrease metals, to clean supports and rinse equipment, etc ... In painting, we mainly use the essence of turpentine, the essences of citrus peel such as orange and the essence of aspic with remarkable dissolving power as well as terpineol, little odoriferous with the very pleasant fragrance of lilac. . By using one of these solvents and another as a co-colvant, almost all the painter's resins (except amber) are dissolved. Solvent list link by family: http://bit.ly/Liste-Solvants. Other essences constitute mixtures of hydrocarbons derived from petroleum such as white spirit and Shellsols® a registered trademark, of which there is a wide range of references ( Shellsol D38 -ShellSol D40 - ShellSol D43 - ShellSol D60- ShellSol DSC ShellSol D70 - ShellSol D80 - ShellSol D90 - ShellSol D100 - ShellSol D100 -ShellSol TC - ShellSol TD - ShellSol OMS- ShellSol T - ShellSol TK - ShellSol TM - Shellsol A. Every Shellsol® has its own unique characteristics that allow them to be used in various fields of application, ad hoc and / or particular. Read the technical sheets of these. List of all Shellsols http://bit.ly/TousLesShellsolsDisponibles

GREEN CHEMISTRY VS PETROLEUM

Green chemistry has already won the battle against petroleum, we are going to see more and more green solvents, also called "biosolvents", coming onto the market, because they come from plants, organic chemistry and not petroleum, they are therefore eminently healthier, in fact they are much less toxic for the most part, because of their non-volatility (without VOCs) like PEG for example. 14 million tons of solvents are used each year in the world, the USA consumes about 3,500,000 tons or about 25%. We consider the advent of the period "Oil" around 1850, this one reigned with hegemony until 1974, date of the first oil crisis, however oil did not say its last word, as long as it did. will remain in the basement of the Earth, yet its days are numbe-

red. at the current rate, the lifespan of petroleum is between 40 years and one century!

SOLVENTS FROM GREEN CHEMISTRY

The future is in green solvents, less harmful and just as effective. There are few references for the moment in the "retail trade", in 2021. We will have to wait a little longer before they are released widely at retail, no more than 5 years, I think. The easy extraction of petroleum decked out blinders mankind for more than 165 years, however, it has made it possible to develop extraction and synthesis techniques that can be transposed into other sectors, including sustainable development, by using renewable biomass produced by living beings (plants, animals, etc. ...). Nature is not lacking in intelligence, on the contrary, it participates in its own enrichment, by making it possible to always have material within its reach, this is what we call reproducibility; oil requires too many resources: it takes everything and it is not renewable, but we have just discovered how to synthesize it in 2018, and fortunately, finally we have passed from the era of black gold to that of green gold, the challenge will be to use it intelligently and wisely.

BIOSOLVENTS AND SUBSTITUTE SOLVENTS

It is this observation that prompted me to do research on biosolvents and materials from the plant kingdom. Here I give you some raw data on green solvents and biosolvents as well as substitute solvents for petroleum products. Biosolvents are produced from oilseed, sugar, grain or pine plants. These include Bioethanol, obtained by the fermentation of sugar or starch, including Glycerol Carbonate, abbreviated Dimethylisosorbide (DMI), as well as vegetable oil methyl ester abbreviated EMHV. [62] Terpene alcohols are extracted from soybean oil. For example d-limonene or citrus essence are potentially the most suitable solvents to replace very dangerous chlorinated solvents. Ethyl lactate is a solvent made from the fermentation of carbohydrates, it is even recognized and approved as a food additive in some countries. Glycol ethers are used as a substitute solvent just like Terpineol, a terpene much less odoriferous than certain natural essences, we can thus use them as a diluent by using very few strong solvents at the beginning since by diluting with an odorless product. we make paintings that hardly show any unpleasant odor. It is also necessary to speak of the bioresins resulting from fatty diacids of plants such as rapeseed, corn, soya, etc., because they can also be used in the synthesis of polyamide, polyester and polyurethane; without forgetting the alkyds made with soya; the list


39

ESSENCES AND SOLVENTS is long, the future is indeed with "vegetable carbon". An oxygenated solvent combined with an aliphatic hydrocarbon can be used successfully to replace xylene. Some solvents are found to be effective in replacing xylene in nonpolar paints with these solvents: 1. Methyl Amyl Ketone: MAK C7H14O 2. N-Butyl propionate C7H14O2 3. Isoamyl Acetate C7H14O2 Biomass is used very little in the world, at the moment 2%, but that is changing exponentially. Natural solvents like turpentine and citrus oil from plants are harmful, but we can use other strategies: Use the cosolvent method, limit our exposure, try using odorless thinners like Shellsol T and Terpineol for your brush maker and try working with an air extractor or windows open. Use very few strong solvents in large bottles to just cover the resin, so you can subsequently dilute with an odorless solvent like Shellsol T, the whole will have lost a very large part of its odor.

THE DISSOLVING POWER

The Kauri butanol (KB) value is used to assess the dissolving capacity of hydrocarbon solvents. It is calculated by titration of a solution of standard Kauri resin (20% by weight in butanol) with a solvent, until a cloud point appears, when it becomes impossible to read a text through the. solution. The amount of solvent used for the titration is taken as the KB value. Usually the Kauri butanol value is a measure of the aromatization of solvents. By using the KB value, it is possible to organize solvents in sequence: aliphatic hydrocarbons <naphthenic hydrocarbons <aromatic hydrocarbons. In my table above, I used it as a standard measure of the solubility power of the painter's materials, not as a measure of aromatics, since we decided to substitute them, if possible by green elements or biosolvents , so this KB scale is somewhat shifted and empirical. The Kauri Butanol test therefore measures the relative strength of a solvent, but there are other scales such as the Hildebrand parameter, calibrated from 0 to 19, turpentine being at 16 on this scale and toluene at 18. We determine and the ability of solvents to remove residues of resins or other fatty substances is measured using the Kauri Butanol Index (IKB or KB) which appears in standard ASTM D 1133. The higher the KB index, the more powerful the solvent: a measurement of 30 indicates that the solvent is inefficient, a measurement greater than 80 indicates a strong solvent. KAURI-BUTANOL SOLUBILITY INDEX OF SOME SOLVENTS SOLVANT IKB FORCE White spirit

31-33

Poor

TURPENTINE

56

Normal

Dipentene

60

Normal

Alcohol diacetone / Acetone

60

Normal

d-limonene

67

Normal

Citrus essence

75-80

Normal

Aspic essence

~ 85-90

VERY GOOD

Xylene

98

Excellent

Toluene

108

Excellent

Lactacte and Ethyl acetate N-Butyl acetate (smell of nail polish) and Diesters

Très Élevé

Excellent

Glycol ethers Methyl ether from Propylene glycol

Très Élevé

Excellent

Trichlorethylene

130

Excellent

Biosolvent

> 160

Excellent

n-methyl-2-pyrrolidone

> 300

Excellent

100% pure pine essence

> 500

Exceptional

THE SUBSTITUTION OF 21ST CENTURY SOLVENTS

By noting the solubility values fd, fp and fh (see the end of the article), it will thus be possible to choose which solvent is better than another. We will also take care to always note the pH of the solvents alone, before mixing them together, then mixing them, because the mixing can be improved by adding to a solvent, an acid or a base, depending on its pH: to replace a solvent with another, sometimes it is necessary to increase the pH, for example that of n-butyl acetate by adding a base such as a little triethanolamine.

REVOLUTIONARY METHOD OF DISSOLUTION

When you have to dissolve resins, use the method of "mechanochemistry", it is a branch of chemistry which deals with the chemical behavior of materials under the effect of a mechanical action, it is a technique which is not not so new and which makes it possible to use much less strong solvents, because we use organic and intermolecular chemical reactions, in the electric mill and then by very fine grinding with mortar using a pestle or by mechanical grinding with l 'Using ball mill, capable of generating greater crushing force; finally, take the time factor into account. The very fine grinding of the resins in a mortar makes it possible to make a flour, so you will use very few solvents. There is also a trick like dissolving the copal resin, which consists in wetting the resin in block with very little strong solvent, while it is still in pieces, then to grind it a few weeks later in order to '' constitute a paste that will be left to soak for a few days, we finish by adding a less strong and less harmful cosolvent in order to achieve the final varnish, all this with little heat, the only caloric value having been performed during the grinding . For example start with very little aspic essence then end up diluting with shellsol T which has no odor obviously it is a little harmful but only with prolonged contact so just be careful or wear gloves. In 2021, we have products that do not smell, they are not at all bothersome.


40

ORIGINAL DISSOLUTION METHODS THE COSOLVENT AND HEAT METHOD When you have to dissolve your resins, also think of the "cosolvent" method, the addition of a second, or even a third solvent will come with the help of the first solvent, jointly the latter will improve the dissolution of the solute , it works wonders. The most used cosolvents are: ethyl acetate, water and ethyl alcohol, which come with the help of aspic and orange essence, turpentine and Shellsol T, but between them also each other. Think about moderate heat, simply by placing the flask on the grid of an electronic heater, then shaking the mixture every 2 min, this allows a very sharp heating of the solution, since here we use forced air on the walls of the container, all around and not a simple bain-marie, which heats part of the flask and which is much more difficult to manage, not to mention direct heating directly from the container which is very uncertain. I am speaking here only for the dissolution of small quantities of resins, one liter maximum, and not for making glues and plasters, although I heat my plasters this way! DISSOLVING RESINS BY PULSED HOT AIR By pulsing hot air through an electronic heater (it's the one in my workshop), as it has a grid, I place the bottle on it, see photo below, the heat will heat the glass container on all sides exposed to the breath, I shake the heated flask at a moderate temperature between 30 and 70 ° C : thus the glass which heats up will increase the temperature of the solvent which will heat the resin, therefore it dissolves very gently cut closed.

it, it is the glass which communicates the heat to the contents, thus we arrive to heat just what is needed, that is to say the exact heat, because as soon as the resin begins to dissolve, we stop exposing the glass, and therefore the solvent. Very clear varnishes are thus produced, since little heat is used; as we are working with a closed container, there are no vapors emanating in the workshop: check the "closed cup" temperature of the solvent, before starting. Take care never to saturate the workshop with toxic fumes, which is why this method of dissolving resins is perfect, certainly original, but very practical: it is ideal for dissolving small quantities of resins, up to one liter, without to make very concentrated solutions, which can then be diluted cold with Shellsol T or another essence such as terpineol. I use a Silvercrest © electronic heater, with 3 power levels of 1000, 1300 and 2300 watts, it also has a remote control, the temperature is adjustable from 5 to 37 ° C maximum. However, I manage to heat the glass up to 80 ° C with this method by leaving it longer, it is more than enough to dissolve many resins, time does the rest. You have to remove the glass and shake it every 60 seconds to 3 minutes, so as not to risk overheating it and risk breaking it. A dedicated model would be preferable because it is safer, but I don't know if it exists.

In this way, the heat emitted does not matter since we remove the glass bottle every 2 minutes or so, to shake

Electronic pulsed air heating to heat the container over very moderate heat which heats the solvent which dissolves the resin. In winter it's even more practical!


TERPINEOL - FATTY ESSENCE AND ASPIC TERPINEOL

CAS N° 8000-41-7. Formule C10H18O. It is a ~ 62.3% alpha-terpineol turpentine alcohol, obtained from purified turpentine by fractionation, which is in the form of a clear, barely yellow liquid, a natural monoterpene alcohol which can be isolated from various sources such as cajeput essential oil, pine essential oil and petit grain essential oil, especially modern varieties (2019). Refraction Index ~ 1.4800 - 1.4855 Flash point ~ 200 ° C | Water content ~ <0.1% Relative density ~ 0.931 - 0.935 It is slightly soluble in water and 70% in ethanol. It does not contain more than 4% of low boiling point substances distilling below 214 ° C. It is a clear, barely yellowish liquid with a high viscosity, reminiscent of glycerin. Its high viscosity is very pleasant under the brush, moreover it is a paintbrush thinner which replaces turpentine for oil painting. It is also an excellent solvent for synthetic resins and a co-solvent for natural resins to easily dissolve mastic with turpentine, plus its odor is pleasant. Terpineol removes brush marks and allows for leveling of the paint, as it pulls the paint. Oil paint applied with terpineol dries completely, leaving a matt film. Due to its lilac scent, terpineol is also used in soap making. Store at a temperature between 10 and 20 ° C.

THE FATTY ESSENCE

It is of turpentine that was allowed to oxidize upon contact with air, it thus gives a viscous liquid, highly soluble in alcohol. It is sometimes used as a plasticizer in alcohol-based varnishes, but it is especially useful as a binder in painting techniques for porcelains and enamels.

Fatty essence that I made by letting turpentine oxidize for months. This one is 20 years old : I kept it by experimentation to check its stability and plasticity over time.

THE ASPIC OR SPIC KNOWN AS THE ESSENCE OF LAVENDER

Scientific name Lavendula Spica DC, the essence of aspic is native to several countries, including France, Spain and Yugoslavia for the essence of commerce. There are 28 varieties of lavender, but only 3 are valid for painting. Here are the 9 CAS numbers that I have listed and that are found in cosmetics, so you will know which one to choose. The first 3 have a very strong dissolving power; the best is the Spica, in my experience, although I also managed to dissolve mastic resin with lavandin, but it turns strongly yellow. Always using fresh essences avoids this pitfall. 1. Lavendula Spica N° CAS 97722-12-8 2. Lavandula Latifolia N° CAS 84837-04-7 3. Lavandula Angustifolia N° CAS 90063-37-9 4. Lavandula hybrida N° CAS: 92502-71-1 5. Lavandula hybrida abrial N° CAS 93455-96-0 6. Lavandula hybrida grosso N° CAS 93455-96-0 7. Lavandula hybrida grosso N° CAS 93455-97-1 8. Lavandula hybrida barreme N° CAS 93685-88-2 9. Lavandula angustifolia Acétylé N° CAS 94334-13-1 Most of them are harvested by hand, which is why the essence is so expensive. Those having a strong dissolving power are the Spica and the Montblanc known as "of better quality", but when we compares their composition by weight, the Spica is richer in essence than the Lavendula Angustifolia and the Lavendula vera, if the the essence of aspic that is currently on the market (2021) is indeed the real Lavendula spica!

41


42

ASPIC ESSENCES Modern aspic composition Lavendula Spica CAS N° 97722-12-8 Component Terpineol Pine essence Turpentine Dipentene Limonene EUCALYPTOL Camphene Terpenyl acetate Cedarwood essence Camphor Myrcene Acetophenone

Composition of lavender "Monblanc" Lavandula Angustifolia CAS N° 90063-37-9

CAS N° 98-55-5 8002-09-3 8006-64-2 138-86-3 5989-54-8 470-82-6 79-92-5 8007-35-0 85085-41-2 76-22-2 123-35-3 98-86-2

% ~ 26 ~ 19 ~ 19

Component N° CAS % 3.7-Dimethyl-1.6-octadien-3-ol 78-70-6 25-50 Alpha Pinène 7785-26-4 2.5-5 Beta-Caryophyllène 87-44-5 1-3 Terpinène-4-ol 562-74-3 1-3 3.7.7-Trimethylcyclo(4.1.0) 13466-78-9 < 2 hept-3-en Myrcène 123-35-3 <2 Béta Pinène 18172-67-3 < 2 Trans-Anéthole 4180-23-8 < 1

14.5 ~9 ~5 ~ 3.5 ~2 ~1 <1

Lavendula Spica is largely composed of 72.69% ethereal oils and 27.31% odorous substances, it is colorless when fresh, then it turns yellow over time. It has a strong, pervasive and overwhelming odor, which partly disappears in 24 hours. Optical rotation = + 4 ° / -15 ° Density at 20°C = 0.880 - 0.930 or 0.893 g/ml at 25°C Boiling point = 183 ° C | Flash point: 57 ° C. Refractive index at 20 ° C = 1.454 - 1.490

1 -Fine or True lavender: Lavendula Vera It is found naturally or in cultivation on dry hills between 600 and 1500 meters. It gives a refined essence very appreciated for its aromatic qualities. 2 -Aspic or large lavender: Lavendula Spica DC It grows wild and spontaneously between 600 and 800 meters above sea level. Its essence is very camphorated. It is used in paints and varnishes. 3 -Lavandin Hybrid species created around 1930, from the crossing of true lavender and aspic which reproduces only by cutting (hybridization) of True Lavender (1) and Aspic (2). Lavandin is cultivated at much lower altitudes, ge-

Hydrodistillation Thermometer

Water cooler

Mixed water + salt or water + pumice stone

Essence

Water

Arrival and departure of water

Lavender

Balloon heater


ASPIC ESSENCE AND TURPENTINE nerally around 400 meters, for its resistance and yield qualities. It is the most commonly planted lavender in the gardens of Provence. There are several varieties of lavandins (grosso, abrial, super, etc. ...). Lavandin is more camphoric than true lavender, however its price is less than aspic and true lavender. Aspic essence 2017

43

these will be entrained by the water vapor and then recovered in another container after condensation by the refrigeration tube. The distillate contains an aqueous phase as well as an organic phase consisting of essence. The essences that we want to extract are organic compounds which are partly soluble in water. Salting is the method of making the compounds in the plant less soluble in water by adding salt. This will make it easier to recover the essence of lavender. Finally, the settling is performed in an ampoule of the same name, in which the previous mixture separates into two immiscible phases. 1. in the lower part we find the heavier aqueous phase 2. above there is an organic phase, of lower density, containing the essence of lavender. The result is dried to remove the water that could be retained in the organic phase, then filtered to collect only the pure lavender essence.

TURPENTINE

Lavender essence and Aspic essence

I use aspic for the production of cold copal varnish, but also to dissolve all the other resins with the long wetting method, with mechanochemistry and also as a cosolvent in very small doses. It is completely soluble in ethanol. Aspic is prohibited in art restoration, because it remains trapped in porous bodies, it can cause softening of the layers of young paintings. I use it in a very small dose, because of its strong smell, at the end of the mechanochemical process, because it allows to dissolve many natural and synthetic materials, if you are patient, then you add shellsol T as a cosolvent and voila, we obtain a varnish which shows very little odor, at least bearable. Essence turns yellow faster if left in the light!

HYDRODISTILLATION

The technique of hydrodistillation is the distillation of an aqueous solution containing an organic compound immiscible with water. See diagram on left page. A mixture of water, plant such as lavender flowers and pumice stone are boiled to stabilize the blend and allow a uniform temperature of the mixture. The cells of the plant will explode and release the non-water soluble chemical compounds contained in the plant,

It is the volatile, 100% part of Pinus Maritima with CAS number: 8006-64-2, the resin or "pine gem" that flows from maritime pine. The terpene solvents that make up turpentine are obtained from pine trees and sometimes as a mixture for lower quality varieties as a by-product of the citrus industry. Turpentine essence is a mixture of two hydrocarbons: Pinene and Nopinene with a chemical composition: C10H16. A good essence of turpentine should not leave any traces if applied to a piece of glass. Apart from the regional varieties, the Portuguese variety, which we find from time to time, at some suppliers is surely the best, because it is very pure, moreover, it has a pleasant smell. This resin is collected by tapping and then distilled with water. This method has remained unchanged since ancient times, Pliny describes the process. Using a still, a distillation apparatus, the gem is purified and then rectified in order to give it a quality suitable for use in painting. These are the oldest solvents used in painting, they predate Egyptian civilization. The main solvents in this group are turpentine, dipentene and pure pine oil with a KB of 500. There are species of turpentine from various origins such as Bordeaux, Landes, Portugal and Turpentine from portugal 2017


44

TURPENTINE - THE ESSENCE OF ORANGE AND ALCOHOLS all places of exploitation. regional. I buy it when it's available again because it took 20 years last time to see it on the market again, so when you find it, take advantage. Turpentine is used to make the famous "Rubens Gel", to dilute paints and to dissolve soft resins such as Chios mastic and dammar resin, shellac, etc. Refractive index from 1.46 to 1.48 Boiling point ~ 149 to 180 ° C Melting point ~ -50 to -60 ° C Relative density (water = 1): 0.9 Flash point ~ 30 to 46 ° C Auto-ignition temperature: 220 to 255 ° C I wouldn't say it's the best of all solvents, far from it, but it's a really good thinner, although the odorless Shellsol T has my preference for thinning. Turpentine has a strong, pervasive odor. Additionally, due to their unsaturated structure, turpentines are restricted by air pollution regulations. ORANGE ESSENCE CAS No. 8028-48-6. It is composed of 97-100% by 4-Isopropenyl-1-Methylcyclohexene more commonly called turpentine from oranges or citrus fruits from which the essence is obtained by cold pressing. Chemical Formula C10H16 Density 0.83 - 0.85 g / ml. Refractive index = 1.4727 Boiling temperature = 175 - 178 ° C. Flash point Closed cup = 45 - 51 ° C. Auto-ignition temperature = 237 ° C. It is an "essential oil", the citrus terpene also known as "d-limonene", obtained by pressing and distilling orange peels: they contain between 0.3 and 0.5%. The advantage of making citrus essence yourself, in addition to economic reasons, but also olfactory, is that you can play on its strength and obtain a product that is much less fragrant. Normally these essences give off less unpleasant odors, but they are allergenic like all essences. It has a very good dissolving power which is stronger in comparison with turpentine. Orange essence is fatter than the other essences, I noticed that it evaporates more slowly too; moreover, it gives sudden headaches.

HOME-MADE RECIPE FOR ORANGE ESSENCE Take the skins of the oranges, taking care to remove the white skin, pass them through a fruit blender, place the liquid in a cone-shaped glass, then leave to settle for 24 hours: two distinct products will appear. Get the more transparent of the two for pure citrus essence. This essence can be used as a one-off replacement as an oil-based paint thinner. You can also put the mixture after decanting in the freezer to solidify the aqueous part to recover the essence.

Water cooler

Cold Water

Lukewarm water

Balloon heater

Water Orange peel

+ distillate

Orange peel distillation

ALCOHOLS AND ACETONE They form a very large class of organic products that are non-nitrogenous, that is, containing only carbon, hydrogen and oxygen as a building block. The term "alcohol" in the painter's trade is used to designate not a single product, but a whole chemical family, such as denatured ethyl alcohol made with methylene containing 35 to 65% of various impurities, including acetone at 25%. Acetone is part of the ketone family and is found in a specific proportion in methylene, it dissolves certain gums and resins. It is a liquid, colorless, very fluid product with a pleasant, but noxious odor. It was discovered in 1754 by Courtevaux who called it pyro-acetic ether with a boiling point of 56.53 ° C and a relative density of 0.819 (at 0 ° C). ETHANOL OR ETHYL ALCOHOL AND METHANOL

They are saturated hydrocarbons with the Chemical Formula: CH3-CH2-OH for ethanol and CH3OH for methanol, the common active ingredient of which is ethane. They serve as surfactants in art restoration, lowering the surface tension of water and other polar liquids, allowing liquids to penetrate stubborn surfaces. Ethyl and methyl alcohols denatured at 90 ° and 95 ° by volume are good wetting agents. They are used as wetting agents for certain gums such as tragacanth, for example, in the preparation of temporary varnishes with dammar resin, in the restoration of works of art and in cabinetmaking for pad varnishes, etc. ...


WHITE SPIRIT They are both corrosive and harmful. They are very volatile and they evaporate without leaving a trace. For ethanol : Density: 789.00 kg / m³ Molar mass: 46.06844 g / mol Boiling point: 78.37 ° C Melting point: -114 ° C

Ethyl alcohol

Alcool au méthanol à 95°

WHITE SPIRIT CAS N° : 64742-49-0. They are solvents, mixtures of aliphatic and alicyclic saturated C6 to C12 hydrocarbons with a typical maximum content of 25% of alkyl aromatic hydrocarbons, which are obtained by the distillation of crude oil by collecting only the fractions which distil. between 150 and 190 ° C, whose distillation curve is very similar to turpentine. The composition and the dissolving power of white spirit depend on the nature of the petroleum and the grade which follows the name in general; so you can find white spirit at 30/75, at 60/95, at 100/140. A good white spirit should be crystal clear and clear like water, it should have a specific gravity between 0.770 and 0.790, a distillation temperature of ~ 140-200 ° and an evaporation rate at 20 ° C of about 53 seconds. White spirit should not grease after evaporation and its odor should not be too strong, it should not smell of petroleum. It is sometimes adulterated with a derivative of turpentine, pine oil, terpiWhite spirit

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neol or terpinolene. I use white spirit only for rinsing material not for painting. Its slight dissolving power for 30/75 varieties is very useful in restoring works of art for cleaning varnishes and paints, pure or mixed with ethyl alcohol or acetone. CHARACTERISTIC OF 30/75 WHITE SPIRIT • 50 % = Pentane CAS-Nr: 109-66-0 • 30 % = Hydrocarbons C6, Isoalkane, <5% n-Hexane • 20%= Hydrocarbons C6-C7 Isoalkane Cyclène <5% • < 5 % = n-Hexane, CAS-Nr: 110-54-3 • < 15 % = Cyclohexane, CAS-Nr: 110-82-7 Boiling temperature: 36 to 98 ° C Evaporation rate: 13 (Butylacetat = 1) Vapor pressure: 400 hPa 20 ° C Density: 0.67 g cm3 at 15 ° C immiscible in water Auto-ignition temperature> 200 ° C Kinematic viscosity at 20 ° C = 0.3 mm2 / s CHARACTERISTIC OF 60/95 WHITE SPIRIT Mixture of C5-C7 paraffinic and naphthenic hydrocarbons. • < 75 % Hydrocarbones, C6-C7, n-Alkane, Isoalkane Cyclène, <5% n-Hexane • < 60 % Hydrocarbones, C7, n-Alkanes, Isoalkane, Cyclene • < 5 % n-Hexane de N° CAS: 110-54-3 • < 40 %Hydrocarbons, C6, Isoalkane, <5% n-Hexane • < 100 % Hydrocarbons, C6-C7, Isoalkane, Cyclene, <5% n-Hexane • < 1.5 % de Cyclohexane CAS-Nr: 110-82-7 Cyclohexane and n-hexane are components of the carbonaceous hydrogen mixture. Melting temperature: <-20 ° C Boiling temperature: 48 - 105 ° C (ASTM D1078) Flash point: <0 ° C (ASTM D 56) Upper explosion limit: 8.3 Vol.% Lower explosion limit: 0.6 Vol.% Vapor pressure: 100 to 200 hPa (20 ° C) Density: 0.65 - 0.8 g / cm3 (15 ° C) Solubility in water: practically insoluble Auto-ignition temperature: 200 ° C Kinematic viscosity 0.3 mm2 / s at 20 ° C CHARACTERISTIC OF 100/140 WHITE SPIRIT N° CAS: 64742-49-0 hydrocarbons, C7-C9, n-Alkanes, Isoalkanes, Cycloalkanes. Mixture of paraffinic and naphthenic hydrocarbons Boiling range 100 - 142 ° C Aromatic content 0.01% (m / m) Density (15 ° C) 0.720 - 0.748 kg / l Refractive index (20 ° C) 1.403 - 1.416 Water content 0.01% (m / m) Flash point: <10 ° C Evaporation rate: 1.4 (Butylacetat = 1) Upper explosion limit: 6.8 Vol.%


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SHELLSOLS Lower explosion limit: 0.9 Vol.% Vapor pressure: 35 hPa (20 ° C) Vapor density:> 1 (Luft = 1.0) Density: 0.725 - 0.748 g / cm3 (20 ° C) Solubility in water: not very miscible Coefficient of variation (n-Octanol / Water): 4 - 5.7 Auto-ignition temperature:> 200 ° C

THE SHELLSOLS OR PETROLEUM SPIRIT

Shellsols® is a registered trademark of petroleumbased solvents, of which there is a wide range of references including the Shellsol D38 -ShellSol D40 ShellSol D43 - ShellSol D60- ShellSol DSC - ShellSol D70 - ShellSol D80 - ShellSol D90 - ShellSol D100 - ShellSol D100 -ShellSol TC - ShellSol TD - ShellSol OMS- ShellSol T - ShellSol TK - ShellSol TM. Shellsol A. They are mixtures of light saturated hydrocarbons, with a variable number of carbon atoms (C7-C11), free of aromatic compounds, i.e. they contain less than 0.1% by weight of benzene . Petroleum essence is a very volatile solvent which does not leave a greasy film. According to the reference (Shellsol T), it is less odorous than the essence of Turpentine. They are less "fatty" solvents (when fresh) than vegetable essences, plus they evaporate less quickly than conventional natural essences. Mineral spirits are used to dissolve non-polar resins, to lengthen oil colors and to thin some varnishes. According to the reference (Shellsol A), they have a strong penetrating power, running the risk of causing a leaHydrated mineral spirits are used to ching phenomenon by reduce the shine of acrylics and to crossing the paint film delay their drying. to end up in the lower layers. Too much petroleum spirit makes paints dull. Each Shellsol® has its own unique characteristics which allow it to be used in various fields of application, specific and / or specific. Refer to their respective technical sheets on the Shell® website: https://www.shell.com/business-customers/ chemicals/our-products/solvents-hydrocarbon/aliphatic-mineral-spirits.html

SHELLSOL "A", A SUPER SOLVENT

Solvent having a high dissolving power and high-boiling, slow evaporation and of which the flash point is high. It is a solvent for natural resins, but it dissolves very many synthetic resins. Shellsol A can be used in place of toluene and xylene. It has a very strong smell, very pronounced aromatics, which unfortunately makes it harmful. To replace it, you will have to identify the resin you want to dissolve, then use the appropriate solvent, you can also use the mechanochemistry method, so you use little solvent to dissolve the resin, you finally dilute with a co-solvent without odor like Shellsol T.

Shellsol A after staying for 10 years In the bottle staying at right

Shellsol A original bottle

SHELLSOL T AN ODORLESS SOLVENT

ShellSol® T is a highly refined and hydrogenated aromatic derivative to convert aromatics into cycloparaffins. This deep hydrogenation results in products of controlled composition with a low percentage of aromatics, therefore, Shellsol T has absolutely no odor, it is very pleasant to use, it is very useful in poorly ventilated environments, it is why it advantageousShellsol T ly replaces turpentine and aspic for allergic people. I use the most cosolvent and thinner. However, be careful not to spray yourself with it, as Shellsol T is harmful, like all solvents.


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SHELLSOLS PROPERTIES OF 4 SHELLSOLS PROPERTIES

SHELLSOL® T

SHELLSOL® D70

SHELLSOL® D40

SHELLSOL® A

Density at 15 ° C, kg / liter

0,761

0.789

0.766

0.895

Refractive index (at 20 ° C)

1,4240 à 1,4310

1,4300 à 1,4500

1,4250 à 1,4360

1.4950 – 1,5040

<1 ppm

<1 ppm

< 5 ppm

> 61°C

74°C

> 38°C

62.8 - 65°C

185-215°C

190-250°C

145-205°C

155 – 185°C

110

800

55-70

45

Sulfur

max.

Flash point Boiling point Relative evaporation rate (Ether = 1) DIN 53170 Benzol content, mg / kg Molecular weight

<3

<3

<5

< 0.01

174 g / mol

140 g / mol

130 g / mol

26

28-29

32

94

24 mN/m

26 mN/m

25 mN/m

30 mN/m

<0,2 % du Poids

<0,4% du poids

> 97% du poids

171

Quantity of Kauri Butanol Standardized solvent measurement

Surface Tension at 20 ° C Du Nouy ring Method Aromatic Content

1 mg / kg

max.

g

/ mol

500 mg / kg

SHELLSOL D40

It consists largely of C9-C11 paraffin and naphthenics (processes relating to the field of petroleum processing). It is used as a thinner for non-polar acrylics such as Plexisol® P550 and as a solvent in the production of varnishes with synthetic resins. Acetates (acetic acid + an alcohol) are widely used as solvents with synthetic resins, but also as a cosolvent with natural essences, due to their strong dissolving power, their less unpleasant odor: the latter disappears quickly (~ 10 min ). They evaporate quickly and when mixed they accelerate the evaporation of other solvents.

to be able to apply them easily, taking care to shake the 2 solvents well ; when mixed with the alkyd resin, the paint hardens very quickly and becomes very shiny after drying. Brushes should be rinsed with pure ethyl acetate before cleaning them with soap, because non-polar synthetic resins, once dry, are not dissociated by soap and water. If afterwards, a cloth soaked in diluted ethyl acetate is passed over the varnishes or paints, they are made matt, this allows an increased shine to be tempered.

ETHYL ACETATE : A SUPER SOLVENT

CAS No: 141-78-6. Chemical Formula: C4H8O2 It is a medium polarity solvent resulting from a reaction between acetic acid (vinegar) and ethanol (ethyl alcohol). It is used in many applications, in particular as a solvent for the preparation of varnishes, lacquers, inks and thinners, in addition to dissolve all acrylic resins of Paraloid®, PolyVinylButyral, Plexisol, polyvinyl acetate and other solid acrylic resins ; but it is also used as a setting accelerator if it is mixed with paints, it is sufficient to make a strong 40% solution in ethyl acetate and ethanol, for example of Paraloid B82, or of PVB at 1 : 7, then mix it with the paints you want to speed up, drying is immediate depending on the dose, the more you add the faster it evaporates and the paint hardens. I tested it with various paints and as a varnish, it allows to make very shiny varnishes with the Paraloids, you have to dilute them with a little Shellsol T or essence

+ 2 hours

30 g of Paraloid B 82 in 100 ml of ethyl acetate

Paraloid B 82 is completely dissolved in ethyl acetate after 2 hours


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CYCLOHEXANOL When mixed with Paraloid and Laponite or tylose, this allows very easy application with a knife, since there is thus a longer opening time allowing the paint to be applied for a very long time, the more the film is more mat according to the Laponite report. Ethyl acetate is a transparent liquid that has a very strong and fruity odor. Ethyl acetate is miscible with many organic solvents such as ethanol, acetone, diethyl ether, aspic essence, shellsol T (shake and mix well), alkyd resins , oils, etc. and it can be gelled with C300 tylose if necessary. Explosive limit between 2.1 and 11.5%. Explosive mixtures of air and steam are possible under certain extreme conditions! Water solubility 61 g / l. | Self-igniting = 460 ° C. Melting point - 83 ° C and boiling point 77 ° C. Density 0.902g / l at 20 ° C Vapor density (air = 1): 3.04. | Flash point: -4 ° C. It is a very good substitute for chlorinated solvents (check beforehand). It evaporates faster than ethyl alcohol. Ethyl acetate is not very toxic, however its slight toxicity is doubled, if it is mixed with ethanol or ethylene glycol.

CYCLOHEXANOL OR CYCLOHEXYL ALCOHOL ALSO KNOWN AS HEXAHYDROPHENOL

CAS No: 108-93-0. Chemical Formula C6H12O Cyclohexanol, C6H12, is formed by the oxidation of cyclohexane, C6H11OH. In the formation of cyclohexanol, a hydrogen atom on the cyclohexane ring is replaced by a hydroxyl group (-OH), this is how it becomes an alcohol. Cyclohexanol is a light aliphatic alcohol, an alcoholic organic solvent which is in semisolid, semi-liquid form depending on the ambient temperature; it solidifies below 20 ° C, it changes to a liquid state by absorbing moisture from the air. The hotter it is, the more it gives off a characteristic camphoric odor, and this from 30 ° C. around 15 ° C it becomes solid and its odor is less pronounced. Cyclohexanol is a viscous, moderately flammable alcohol. Its polarity is medium (50) and therefore it is used as a pore-forming solvent in processes for cleaning works of art by swelling in several stages, because it induces low to moderate degrees of swelling of the paint layers. It mixes well with water. It is used in the treatment of leather, in the manufacture of lacquers, paint and varnish strippers, in pure varnishes and as an intermediate in the preparation of plasticizers. In painting, it is mainly used in small doses <10% mixed with butyl acetate to stabilize and as an intermediate agent to homogenize gels made with acrylic and synthetic resins. It is used in metallic effect paints, to make mixtures composed of metallic pigments or precious metals, resins, waxes and oil.

Cyclohexanol is also used to stabilize and homogenize soaps. It is an alcohol of oily appearance, which takes a long time to evaporate: for example mixed pure with wax, in summer, after 2 days, a film applied to ceramic was still not hardened. Do not confuse cyclohexanol with other solvents prefixed with "hexane", which largely contain a linear hydrocarbon nhexane, which is extremely harmful just like methylene chloride. Cyclohexanol is soluble in ethanol and is miscible with ethyl acetate and vegetable oils, such as linseed oil. It is mainly used as a mixture, to plasticize or homogenize paints or gels. I use it to slow down fast evaporating solvents Cyclohexanol taken by like ethyl alcohol or ethyl acetate. mass at 19 ° C. Solubility in water: 3.60 g / 100 ml at 20 ° C 4.3 g / 100 ml at 30 ° C Refractive index ~ 1.4641 to 1.4656 auto-ignition temperature ~ 300 ° C. Density ~ 0.9624 g / ml melting temperature ~ 25.1 to 25.9 ° C boiling temperature ~ 160 to 162 ° C Flash point closed cup ~ 63-64 ° C Gas / vapor density ~ 3.5 Vapor pressure ~ 130 Pa at 30 ° C ~ 300 Pa at 40 ° C ~ 620 Pa at 50 ° C Explosion limits, flammability in% in air: 1. Lower limit: 2.7% 2. Upper limit: 12% Listed toxicological values: H302 - H315 - H227 H332 - H335. Pure cyclohexanol can be toxic by inhalation or skin exposure.


N-BUTYL ACETATE AND ISOAMYLE ACETATE N-BUTYL ACETATE OR BUTYL ACETATE

CAS No. 123-86-4 Chemical Formula = C6H12O2 It is a solvent of medium polarity, not very harmful, which denotes a very characteristic odor of "nail polish", which evaporates rather quickly. It can be used to dissolve many synthetic resins like Paraloid, Polyvinyl Acetates, Ketones, Aldehydes, Plexisol, etc. It is one of the best solvents in Paraloid. It can be thickened, like many solvents, with Tylose C300 (methylcellulose). It is also used as a cosolvent to speed up the too slow evaporation of certain solvents. Density ~ 0.879 to 0.881 Viscosity ~ 560 Mpas at 25 ° C Solubility in water ~ 5.3 g / l (20 ° C) Melting point -77 to -78 ° C Boiling point ~ 125 to 127 ° C Gas / vapor density ~ 4.0 Vapor pressure ~ 1.2 kPa at 20 ° C Flash point ~ 22-26 ° C closed cup. It is soluble in many organic solvents such as alcohols, ketones, ethers, and most hydrocarbons, but it is not soluble in water. Explosion or flammability limits in% in air: 1. Lower limit: 1.7% n-butyl acetate 2. Upper limit: 7.6% Auto-ignition temperature ~ 420 to 425 ° C Toxicological values: H226 - H336 - R10 - R66 - R67

ISOAMYL ACETATE KNOWN AS BANANA OIL

Also known as Isoamyl Ethanoate; isopentyl acetate; 3-methylbutyl acetate. CAS number. 123-92-2 Chemical Formula: C7H14O2 It results from isoamyl alcohol and acetic acid. It is a clear, colorless liquid which denotes a pure banana and pear scent when mixed with ethanol, so it is used as a flavoring agent by confectioners. It can be used as a solvent, cosolvent and as a diluent with other solvents in order to make them less odoriferous, less pregnant. Solubility in water at 20 ° C ~ 0.2 g / l. Insoluble in glycerol, practically insoluble in propylene glycol. Soluble in ethanol, ethyl acetate, most fixed oils and mineral oils. Oral rat LD50 ~ 16,600 mg / kg. Density 0.87-0.90 g / cm3 Refractive index 1,400-1,404 Boiling temperature ~ 142 ° C Melting point - 78 ° C. Flash point (closed cup): 33 ° C. Vapor density: 4.5 (air = 1). Auto-ignition temperature ~ 355 - 380 ° C. Explosion or flammability limit in% in air 1. Lower limit: 1%. 2. Upper limit: 7.5%.

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Toluene known as Methylbenzene

It is an aromatic hydrocarbon, transparent liquid with the Chemical Formula: C7H8 Toluene is produced during the process of making essence and other fuels from crude oil, in the manufacture of coke from coal, and as a by-product in the manufacture of styrene. Toluol is crude toluene. Toluidine is an aniline dye [49] derived from toluene. Methylbenzene can also be used as a fullerene indicator, it is a raw material for toluene diisocyanate. Boiling point: 111 ° C

XYLÈNE

It is an aromatic compound, a mixture of three isomers of benzene. Benzene is a natural constituent of crude oil (aromatic hydrocarbon). Its Chemical Formula is: C8H10. Xylene is a colorless, highly flammable liquid, its melting point is between 47 and 87 ° C, its boiling point is close to 140 ° C, its density of 0.87 is lighter than water in which it is insoluble. Xylene has a harmful effect on the brain, even on short exposures. NOTA BENE I have totally banned toluene and xylene from my practice, since I discovered the existence of the cosolvent method in 2017 and became aware of the mechanochemistry. I urge you to do the same and no longer use these 2 substances which are very dangerous to health. If you see, write "benzene" or "benzene" on a label, definitely don't use it. With the cosolvent method, these products are obsolete for the modern "painter". There are other substances that the painter should do without, including ligroin (it contains <5% n-hexane and <2% cyclohexane), n-hexane, cyclohexane, and all very pure aromatics, because with aspic + turpentine as a cosolvent and citrus essence + terpineol you can do anything. I am talking here about painting, not about the restorer's profession which sometimes requires very strong solvents in small quantities.


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THE POLARITY OF THE SOLVENTS TO DETERMINE THE DISSOLVING POWER

The polarity is expressed by the Fd value : More its value is low, more the solvent is polar

If you know the fd value of a solvent, then you can predict its range of miscibility for a given material. Moreover, by linking the 3 values fd, fp and fh, we can know the range of solubility. By knowing the polarity of a solvent, we know with which liquid we can mix it, ideally: for example we see below that ethanol mixes very well with water since its polarity value is 36. It I was unable to find any evidence for aspic, so I deduced from my knowledge and experience the values fd, fp and fh.

Hexane Shellsol A Cyclohexane White-Spirit

Turpentine Aspic D-Limonene Isoamyle acetate Butyle acetate Ethyle acetate

Cyclohexanol

Acetone Ethylene Glycol Ethanol Methanol

Water

0 18

30 36 42 47 50 51 60 68 70 77

90 94 97 100

Non Polar

Polar

Polarity scale Fd ≈ Dispersion Forces = less polar bonds Fp ≈ Polar Forces = More polar links Fh ≈ Hydrogen bonds = Intermolecular force between 1 hydrogen atom and 1 electronegative atom like oxygen Solvents Water Methanol Ethanol ETHYLENE GLYCOL ACETONE CYCLOHEXANOL ETHYL ACETATE BUTYL ACETATE 30% Butyl Acetate + 70% Terpineol 70% Ethyl acetate + 30% Aspic Aspic essence Turpentine White Spirit Shellsol A

value fd 18 30 36 42 47 50 51 60 65 68 70 (empirical) 77 90 97

value fp 28 22 18 20 32 12 18 15 18 21 25 (empirical) 18 4 15

value fh 54 48 46 38 21 38 31 25 22 23 35 (empirical) 5 6 18


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SOLUBILITY TRIANGLE FOR THE PAINTER

Gums, Glues, Albumin Synthetic resins Natural Resins

Waxes

10

Hardened Oils

90

Oils 80

20

70

30

60

40

Fh

50

Fp

50 40

60

30

70 80

20 10

90

10

20

30

40

50

60

70

80

90

Fd You will find on the internet, a portable version of the Solubility Triangle in Flash at this address http://www.icr.beniculturali.it/pagina.cfm?umn=297&uid=505&usz=1 Thanks to Cristina Pingeot for bringing this restaurateur owner's triangle to my attention, he helped me perfect this triangle for the painter. A huge thank you to Maurizio Coladonato and Paolo Scarpitti for creating this great tool. Grazie a maurizio coladonato and paolo scarpitti.


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THE BALSAMS The Balsams

The balsams consist of the natural dissolution of one or more resins in a volatile liquid, the syrupy and oleoresinous result called "balsam", improves the flow and the adhesion of the oleaginous binders and the oleoresinous mediums. Before using these balms, you should take into consideration that they are all anti-drying, they are most often used for glazes, in the later layers of the work, unless you consider them as a complete technique, Like the masters of the past, for example the VanEyck brothers. The original characteristic of balms is their great plasticity, which also makes it possible to use them as plasticizers of varnishes and mediums. On storage, in the long run, some balsams Crystallize, it is necessary to heat them to restore their original cohesion. I have been experimenting with solid form of Venice balsam from HMB-BDA (Paris) for more than 20 years and is still active. To use it, just heat it in a bain-marie in a little warm turpentine oil : see picture below.

Venice balsam ou Turpentine from Venice

It is secreted by the common larch Pinus larix L, Larix Decidua and Larix occidentalis, exploited in Tyrol, Piedmont in Italy, France to Briançon, Canada and northwestern North America. Formerly it was called "bijon". It is part of the Pinaceae family. The Venice balsam, when cleansed of its water, is as thick as honey, nebulous and translucent, with a caramelgreenish-yellow tint, its odor seems that of turpentine and lemon, with a bitter and aromatic taste. Stored, the balsam does not separate over time and does not harden on the surface when diluted with essence; It becomes fluid at low heat to bain-marie and it is easily sink. This oleoresin contains 15 to 25% of essence, which is soluble in alcohol, toluene, ether, turpentine and oils. It can be used as a glaze medium for the last layers in a ratio of 2: 1 and 1: 1 with black oil. The balsam of Venice is not siccative, like all the basalms, it will be necessary to wait long enough between each layer of painting. Relative density at 20°C = 1.027. Refractive index at 20°C = 1.5193

Venice balsam

Larix decidua By I, Przykuta GFDL via Wikimedia

The Balsam of Canada

It is secreted by a species of balsam fir from the Pinaceae family: Abies balsamea and Abies Canadensis, originally from North America. It is found in the Province of Quebec as far as in Maine (USA), the more southern regions of the Appalachians (a mountain range in eastern North America extending from Newfoundland, Canada) In the north, to the center of the state of Alabama in the south (United States). It is harvested from the bark of this coniferous species during the summer of July to the end of August or even of the beginning of September It is in the form of a clear syrupy substance with the aspect of honey, of a light yellow color, has a sweet odor, very odoriferous, a bit bitter flavor, it is as transparent as water, But it turns yellow over time if it is stored in the dark, its oleoresin also contains a watersoluble alkaloid, and succinic, formic and balsam of canada acetic acids are formed by dry distillation. (Which has exactly the same characteristics as turpentine), camphene (a bicyclic monoterpene of the formula C10H16), about 50% canadinolic acid alpha and beta C16H29COOH, about 15% canadianic acid C19H37COOH, about 5% canadoresene C21H40O and various resin acids.


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THE BALSAMS Density of his essence : 0.862 to 0.865. Density of the balsam ranging from 0.945 to 1.080 Refractive index: 1.53 to 1.55 Il possède une grande réfringence, une transparence parfaite, même à une faible épaisseur, une inertie chimique et une excellente plasticité. It is the perfect plasticizer for varnishes at very low dose. It is soluble in xylene, oils, essences of aspic and turpentine in part. Partially soluble in almost all organic solvents but insoluble in water. It was widely used in optics because its refractive index of 1.55 is close to that of glass. It is used with oil-based paint, oleaginous and resinous materials to plasticize varnishes, to create magnificent glazes and subtle transitions such as wipes or blends if mixed with Rubens gel, it give the pastes a crystalline luster. It is necessary to add a very little and only in the last layers of the work, because it is anti-drying, unless if we allowed a long time between the resumption of layers of painting (1 month). The balsam of Canada, like the other substances in the painter's craft, must not be ingested, not even to taste to identify certain substances. The lethal dose (LD = mg / kg) for humans is 3 to 4 g of Canada Basalm for an individual of 80 kg. For information, a similar balsam is obtained from spruce, hemlock, "Tsuga canadensis" which was studied by Tschirch and Bruning (Archives, Pharmaceuticals, 238, 487). For 100 parts this turpentine contains Canadian acid C19H34, 2%, m.p. 135-136 ° C, 13%, 2% C19H28 canadolic acid, m.p. 143-145 ° C, 0-3% , C19H30 2% melting point 89-95 C ° 48-50%, essential oil 23-24%, canadoresene, 11-12%, succinic acid and impurities, 1-2 parts.

balsam of canada

Tolu Balsam or Balsam of Peru

The Tolu balsam is the product of the trunk of the Myroxylon balsamum L. Harms tree of the fabaceae or leguminous family of up to 15 to 20 meters high, with slender trunk covered with a greyish bark. Peruvian balsam native to Central America is a native New-Grenada tree that grows in Colombia, Peru, Venezuela, Argentina, Brazil, Paraguay and Bolivia. Called "Balsam of Peru", because originally it was imported from this country, but it is no longer the case. It is an aromatic balm that exudes from incisions made in the trunk of the tree, and then collected in tin pots. The bark is detached from the trunk of the tree, then the wood is burned, which activates the flow of the balsam. Tolu Balm has a scented odor and a slightly acid taste. It is presented in the form of a somewhat thick liquid of blackish brown color, similar to molasses. It contains benzyl benzoate, benzyl cinnamate, cinnamic and benzoic free acids, peruviol, farnesol, nerolidol, traces of vanillin and acid esters of toluresinotannol, an alcohol of very complex constitution. Fresh, Tolu balsam is a soft, tenacious, resinous substance that becomes much harder in time, but that fears cold. If a small fragment of balm is heated and pressed between two pieces of glass under a microscope, crystals of cinnamic acid can be seen in the mass. Tolu Balsam is soluble in 3 to 4 volumes of alcohol at 90°.It is also used in perfumery, medicine, expectorant, anti-burning poultice and in the preparation of aromatic substances. We can produce very beautiful brown lacquers with the balsam of Tolu. Density is 1,140 to 1,170. Acid value is 105 to 140 Ester value is 38 to 70. See this blog for another detail on Tolu :

http://jeanne-blog.com/balsam-of-peru-balsam-oftolu/

Tolu balsam


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THE BALSAMS Balsam of Copaiba or Copahu

Part of a genre that consists of 35-40 species of evergreen trees, which can reach a height of 15 meters and native to tropical America and Africa. The balm is extracted from Copaifera officinalis L. which provides the most important production among Copaifera guyanensis Desf, Copaifera coriacea Mart., Copaifera Langsdorffii Desf., Copaifera confertiflora Benth., Copaifera oblongifolia Mart. and Copaifera rigida Benth. It was discovered in 1625 by a Portuguese monk (Manuel Tristaon), who met Indians from Brazil. The word "copaié" comes from the Tupis Amerindiens and means in Tupi language : the tree and its resin. Copaifera grows mainly in Brazilian tropical forests. The balm is obtained by drilling holes in the trunk to the center with a wick and by pushing into these holes tubes of tinplate through which the balm flows. Some trees often provide 30 liters of balm, or even more. The first crop is colorless, with a consistency of olive green oil to pale yellow, and Copaiva Balsam BY Maša Sinreih in Valentina with a peculiar odor Vivod from Wikimedia Commons and a bitter taste. It is an oleoresin which is distilled into an essential oil comparable to the essence of turpentine. But once in contact with the air, its consistency becomes thicker and yellowish, it then becomes a balsam. The hydrocarbons of copaiba are terpenes derived from isoprene plants, formed of five carbon atoms, pinene is one of the terpenes constituting it. Heated terpenes become methanol (CH3OH) and other simple compounds used as fuel and as raw materials in the chemical industry. It is a very interesting balsam, which has characteristics similar to those of Venice balsam, and it is used in the same way. Specific Gravity (20 ° C): 0.958 to 0.993

Copaifera officinalis By Franz Eugen Köhler via Wikimedia Commons

Cross-linked Essence of Copaiba By Itineranttrader via Wikimedia Commons

Balsam or Bordeaux turpentine

It comes from various species of pines, in France, in the Landes and around Bordeaux, it is extracted from Pinus Maritima, Pinus Pinaster, Solander, Germany, Pinus Austriaca L, Pinus Sylvestris L and Rotundata , America Pinus Taeda L and Australis and currently Russia. The turpentine of Bordeaux is a balm with the consistency of thick honey, which separates with time in two superimposed layers, one transparent and semi-fluid and the other resinous with a crystalline aspect. Its smell is strong, unpleasant and its flavor is pungent and bitter. In addition to sylvic acid, this resin contains 15 to 30% of turpentine, which it abandons by distillation with water. This balsam is completely soluble in alcohol, ether, carbon disulphide and fixed and essential oils. It is a balsam, more or less thick, depending on whether it contains more or less turpentine.


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THE BALSAMS Its fields of application are the same as of those the balsams of Venice and Canada, but in my opinion the balsam of Canada is that of all the balms that possess the best characteristics for artistic painting. Its melting point is around 130 °C. Boiling point at 156 °C. Specific weight about 0,856

The Galipot

The Galipot is the Bordeaux turpentine elapsed during the winter, and dried up on the very trunk of the tree. It is very poor in essence. Its a product of little interest for the painter because of its secondary quality, however I mention it because it is often found in old recipes of painting and it is necessary to know that it is possible to replace it with the Venice turpentine or the Canada balsam.

The Rosin or Arcanson

Rosin is the solid residue obtained after distillation of turpentine from Bordeaux originally from Landes forests. It is an oleoresin known as gemstone or pine gemstone that is harvested from species of softwood trees and in particular Pinus Maritima, although in the 21st century it is China that exploits it for the largest Part of Pinus massoniana and Pinus kesyia. Rosin unlike essence which is liquid, is present in a compact and resinous mass, that is insoluble in water but soluble in most organic solvents, such as hydrocarbons, alcohols, ketones, esters, etc. . ... It is a mixture of crude formula C20H30O2 of 4 constituents, including abietic acid, levopivorimaric acid, neoabietic acid and dextropimaric acid, having conjugated double bonds for three of them, which explains the high sensitivity of the rosin to water after oxidation and particularly to peroxidation,

which can cause considerable disruption of the materials with which varnishes are constituted, it is why it should be avoided in artistic painting because of the low molecular weight of Its constituents. After all these observations, it is understood that the use of the rosin would lead to the long, irremediably of the varnishes bleaching. The rosin is used primarily to extract Lapis Lazuli from lazurite and by the musician who rubs rosin on the lock of hair of the bows to allow vibration of the rope. It softens between 90 and 110 ° C.

Strasbourg Turpentine or from Alsace

we collect it from the bark of the white fir, also known as pectine fir or fir from the Vosges, from the fir trees "abies Alba" or "abies pectinata", it is a conifer of the Pinaceae family, an important essence tree for the Forestry in Europe. For 100 parts turpentine of melting point 114-115°C boils at 145-153°C, contains 8-10% abienic acid C13H2O2, crystalline abietric acid and 46-50% abietinolic acids, Essential oil 28-31%, abietoresene 1216%, alkaloid, coloring matter, water and impurities, 2.1%, succinic acid 0-05-0-08 parts. (Tschirch and Weigel, Arch Pharm 238, 411).

Strasbourg turpentine

In general, the pine balsamsAnd balsam firAre to be used sparingly because they have a marked tendency to migrate into the lower layers of the work unless they are used from the start, in this case beware of the embusers or they must be used in conjunction with others resins, in order to palliate the inherent and intrinsic defects, which possess all the balms without exception, a notorious lack of siccativity. Rosin By Jibi44 via Wikipedia


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THE BALSAMS Larch Balsam from Southern Tyrol

Here is an example of a regional production of larch balm from South Tyrol currently in the catalog. The best turpentine of larch, from which are produced essence and balm, is obtained from flows of European larch resin. European larch (Larix decidua) grows in the Tyrolean mountains at an altitude of 1700 m. It blooms between April and May, it is at this time that the buds of the larch grow, the shoots grow at the end of the upper branches. Although the larch belongs to the family of pines, it does not have needles, but leaves that fall at the end of autumn. Trees reach up to 50 m in height and can live for more than 600 years, in South Tyrol in the Ultental Valley, there are 3 larches, whose age is estimated at 850 years! Larch wood is the heaviest and hardest wood among European conifers. Except to make balms, it is mainly used as timber and to make furniture.

Large quantities of turpentine are collected from mature trees from May to October. Holes are drilled in the trunk and wooden tubes are inserted. The flowing balm is perfectly clear and only requires filtration through a coarse stains to get rid of its impurities. This balm should be as clear as possible; If this is the case, after desiccation it will produce a non-yellowing film with an enamelled finish. Compared to other balms, this is the most reliable used in painting with Canada Balm. Antony van Dyck used a balm of this type in his mediums. It is perfect for making glazed and enamelled paints. It should be diluted 1 to 1 with high-quality aspic or turpentine, but it can also be mixed with a rubens gel to make beautiful glazes but they are very long to harden. Abies Alba or Pectinated Fir

Conclusion

South Tyrol Balsam 2017 on raw wood

South Tyrol larch balsam unrefined

This chapter on balms can be developed over time, as some of them, from regional productions, reappear from time to time in the catalog of certain suppliers. If you are lucky enough to get balm or any other material where you live, then use it, it's a godsend to have fresh regional produce, even if they are of lower quality than Materials purchased at the other end of the world; For as has always been the case in art, it is the way in which you prepare your materials which determines their final qualities: for example by purifying an oil of poor quality and then by baking it with siccative, we can do An oil of very good quality, this remains true for countless materials.

"Pinus pinaster" pine forest


57

THE NATURAL RESINS Natural Resins

They are from the vegetable kingdom, such as Chios mastic and animal like shellac. The difference between turpentines is that they are always present in liquid state, resins are always in solid form except latex. There are as many resins as there are plant or animal species that can provide them. The rosin resins are treated at balsam (see Bordeaux Turpentine) and Elemis are resins of Secondary quality or unsuitable in the field of artistic paintings, they lose (very quickly through evaporation) their constituents and the few qualities they had initially. So I will not treat them, and you could replaced them advantageously with sandaraque resin. Elemi is more useful in the field of perfumers than in artistic painting. Only the first resin quality materials have to be used in artistic painting.

It will have to be taken into account to realize the "Medium of Rubens" or "Gel of Rubens" in order not to miss it.Its hardness lies between that of the dammar resin and the sandaraque resin.The mastic, a tri-terpene resin, consists of two resins, one of which is soluble in alcohol with acid reaction, while the other is insoluble, the weight of the latter being 8 to 20% by weight Of the mastic. When it has just been harvested, it contains traces of essential oils. It is completely soluble in hot turpentine and cold in acetone. It dissolves to 90% in 95° alcohol and to 75% in carbon disulphide, it dissolves completely in ether and anhydrous alcohol.

Mastic of Chios, or Scio

This medium hard resin comes from a shrub, the Pistacia Lentiscus L. of the Terebinthaceae-Anacardiaceae family. Mastic is found in Greece and especially at Chios (a Greek archipelago known by the Turks as Sachis adassina or Mastic Island), also known by the Egyptians (who named it "fatti") since about 2700 BC. The inhabitants of the villages who harvest exclusively this resin are called "Masticochora" or "mastic village". Its name "mastic" comes from the fact that it was much used as masticatory in order to perfume the breath and strengthens the gums. The lentisk is also common in Algeria. Its fruit can contain between 20 and 25% of a fat and green oil. Incisions are made on the trunk and on the branches of the lentisk, collecting from 4 to 5 kg per year and per tree, solidified droplets in the form of tears containing inclusions of tiny air bubbles, Elsewhere for that it is called "mastic in tears". The mastic of Chios has a weak balsamic odor, slightly bitter but pleasant enough. The mastic resin was used in antiquity as an antiseptic, and was also used as chewing gum. The mastic softens at about 90 °C and melts at 105 °C. The older she is, the higher its melting point, it can reach 120 °C. Its density between 1.04 and 1.07 can vary by Pistacia Lentiscus L increasing.

Mastic of Chios in tears

Mastic resin to powder with an electric mill


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THE NATURAL RESINS There are 2 kinds of Mastic 1. The mastic "in sorte" also called "mastic female" collected on the ground, it bigger than the mastic in tears, his transparency is less, its darker color varies from yellow to dark brown. 2. The mastic in tears or mastic officinal is more transparent and brilliant, its breakage is vitreous, its coloring goes from greenish yellow when it has just been harvested on the tree to become soon light yellow. It is this one that must be used for the painting and for clear varnishes, this variety is denominated "Mastix Electum". Care must be taken to choose the mastic, because the bigger the tear, the better the quality (although it is not as large as the "in sorte" variety). The mastic makes it possible to produce soft and glossy varnishes. They turn yellow over time, but can be removed easily because they are soluble even after several decades. Mastic varnishes begin to become insoluble when they reach about fifty years, care must be taken to remove final varnishes with Resin mastic of chios 8 years out of mastic every 10 light, the resin loses strength with years. The masage, it must be added a little more tic mainly allows when making varnishes and mediums the realization of the famous Rubens medium, a jelly, of which it is the primordial component in half with siccatived oil with lead. We also realize with the mastic of Chios in conjunction with sandaraque resin of beautiful fat varnishes in the oil of linen or hot walnuts. Chios mastic is the most important resin in the painter's craft, it is a must have, although the synthetic resins in solvent phase replace it increasingly.

and was mentioned for the first time in 1828 by a German apothecary F. Lucanus. The Dammar, most commonly used in painting, is extracted from a conifer, the aganthis dammara, which grows in eastern India and New Zealand. Dammar resin is usually a terpene resin, the major components of the resin. It is soluble in turpentine, aspic essence, alcohol, chloroform, ether and petroleum essences, and in cold and hot oils.It melts at about 130 °C.

Dammar in pieces

The variety "Batavia" is the most prized. It is used to make clear varnishes to replace the more yellow mastic resin and especially much more expensive. Its varnishes are less flexible than those with mastic, but they have a tendency to micro-cracking and become insolubilized with age. As a resin for medium, the problem does not arise since the oil communicates to him his properties. I only use it to make insulation varnishes for the lower layers in oil painting on wood and fixatives for charcoal and pastels, however I plasticize them with castor oil.

Dammar Resins

They are resins secreted by various trees of the Dipterocarps, Hopea, Shorea, Balenocarpus and Vateria family, from large evergreen trees of tropical regions that are found from India to the Philippines and Malaysia. It did not arrive in Europe until 1827 Dammar in powder


59

THE NATURAL RESINS The Sandarac resin

It is a resin naturally flowing from the bark of Callitris Quadrivalvis rich, a kind of thuja articulata, a shrub found in northern and eastern Africa. Sandarac also exists in Australia, produced by The Callitris Preissii, Miq. and another one the Tetraclinis articula.

to not use the so-called sandaraque of Germany taken from the exudation of old junipers, that we can recognizes by heat, with a very characteristic odor. Sandaraque is a resin with which "liquid varnishes" are made by subtle mixtures in aspic essence and oil. See. Recipes. It is necessary to moisten the resin in a little alcohol, then dilute it with turpentine or aspic, it is important to plasticize these varnishes with castor oil which has the advantage of being very clear. The varnishes with the sandaraque are very hot and are well adapted for works treated with pigments of earth, ocher and red. By mixing with the mastic resin, sandarac is my favorite resin to make infinite varnish of all sorts.

Sandaraque resin set to dissolve in aspic essence, the best solvent for natural resins

There are 3 kinds of Sandaraque resin 1. Transparent pale yellow tears 0.5 to 3 mm long and covered with white dust. 2. Common in tears, but darker, ranging from brown to reddish, it is less translucent and contains many impurities. 3. That of Australia in tears is much larger and not transparent. The sandaraque resin is hard and friable, it has a low odor terebinthaceae and a slightly bitter flavor. It softens at about 100 ° C and melts at about 135 ° C, igniting and emitting a rather pleasant odor. Its density is 1.092, 1.05 and 1.006 depending on the sample and the freshness of the resin. Sandaraque is a tri-terpene resin composed by 3 resins that can be separated (including sandaracopimaric acid) but behave identically in solvents.Their study is of little interest. The sandarca is soluble in ether and hot in alcohol, as well as in acetone. It is incompletely soluble in turpentine, but completely soluble in aspic essence even when cold. It dissolves very little in benzine and petroleum ether. The hardness of the sandarca is equal to that of the copal Kauri, but superior to that of the mastic it scratches. As a general rule, it is not falsified, but it is used to falsify the mastic resin, it is necessary

Sandarac resin in tears

Gums-Lacquer or Shellac

The gum-laque comes from the East Indies where it is produced by the female of an insect, the cochineal lacquer, of scientific name Coccus-Lacca, living on different trees and in particular on Ficus Religiosa L, Ficus Indica L, Rhamnas Jujuta L and Croton Lacciferum. The insects are coated by the juices which flow from the stitched surface of the tree and which dry on them, inside the beads thus formed there are larvae which consume the juices and which after mutations pierce the envelope to Escape from it. These beads are colored in reddish brown and compose the lacquer, consisting of a coloring matter, a wax and a resin, this solidified lacquer takes the name of gum-lacquer. The best qualities of shellac are those that are harvested prior to insect hatching. Shellac comes almost entirely from India, although it is also produced in small quantities in Burma, Indochina, and Thailand.


60

THE NATURAL RESINS

3. LEMON shellac in flakes

3. Shellac flakes

9. Shellac dewaxed and bleached

4- Lacquer in granules

4 LEMON shellac

5. Buttons lacquer

8. Shellac Discolored

3.Orange lacquer in scales

9.Gomme dewaxed and bleached shellac

Commercialy, there is shellac in 10 diverse and varied forms, which are listed below :1. the lacquer in sticks 2. the dye lacquer 3. Scale lacquer 4. grain lacquer 5. the lacquer in buttons 6. lacquer in loaves or in shelves 7. wire lacquer 8. the discolored lacquer 9. dewaxed and bleached shellac 10.The shellac wax Shellac is a brittle, friable material whose color varies from brown to light golden-blond and yellowishwhite depending on the treatment it has undergone. Its composition has been studied, but the results vary because the origin of the samples is often indeterminate or unknown. Its crude composition consists essentially of esters of an acid to which the following chemical formula is given : CH3CH2CH2(CHOH)(CH2)7CHOH·COOH namely, the di-hydroxy-fico ceryl acid.Cf.[51] COMPOSITION TYPE OF SHELLAC Resin 74,5% Coloring materials Wax Humidity Residue

6,5% 6,0% 3,5% 9,5%

Constitution expressed in volume: 68 volumes of resins; 10 vol. Coloring matter; 6 vol. of wax ; 5.5 vol. Nitrogenous material; 10.5 vol. Of foreign bodies. The shellac is actually a form of natural plastic. The wax contained in the gum is formed from a mixture of several myricic ethers with more than 50% free myric acid and a small amount of free or combined ceryl alcohol, but the proportions of these various elements vary according to the treatments the raw lacquer was subjected to. The dye lacquer contains up to 50% dyestuffs, not more than 0.05% for 91% resin, the tablet consists of 88.5% resin, 2% nitrogen and 2.5% foreign bodies. Gum-shellac wax is mainly a mixture of acid esters (about 60%) and free alcohols (about 35%). In addition, it contains small amounts of hydrocarbons, penta and untriacontane or hentriacontane, a linear hydrocarbon of the alkane family of formula C31H64 and with about 1% of acid resin. The shellac is incompletely soluble in ether, which dissolves only 6% of its wax, also in chloroform and carbon disulphide; For this reason it is sparingly soluble in cold alcohol, unless it is allowed to digest very long in the latter.


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THE NATURAL RESINS The shellac is soluble for a time in hot alcohols, For on cooling the wax makes it become turbid again and separates itself. It is insoluble in oils, but it dissolves readily in alkaline solutions such as ammonia, borax, sodium carbonate, sodium hydroxide, caustic and carbonate solutions as well as in various organic solvents. It is precipitated from these solutions by acids. Water dissolves only its coloring matter, which is also very soluble in sulfuric acid and dilute hydrochloric acid. Its melting point is between 77 and 82 ° C. The shellac is bleached by very complicated means, often very expensive and difficult to realize by the layman.

lynesia, New Zealand, New Caledonia and the northSouth America. There are 5 main types of copal recognized as such in commerce and which are: 1. The Copal of East Africa, including Zanzibar 2. The Copal of West Africa 3. The Copal of Manila 4. The Copal Kauri of New Zealand and New Caledonia 5. The Copal of South America The copal from Zanzibar from where it comes is sorted, then packed for export. The copals of East Africa are fossil resins, harvested mainly in localities where copal trees have disappeared. They are most likely the product of Trachylobium species. West African copals are harvested along the coastal regions of Sierra Leone in the Congo. The finer varieties are fossil or semi-fossil and the poorer varieties are derived from living trees. The best varieties of copals come from the Congo, Angola and Benguela, the average qualities of Sierra Leone and Accra, and the worst of the Niger.

8. Shellac Discolored

Shellac is mainly used (although often replaced by synthetic resins) in buffer varnishes, As a binder for inks, and as an insulating varnish. The best way to use shellac is to bind the inks, but it must be saponified with an alkaline solution, and then neutralize the alkali (by means of a sulfurous acid, for example), which will precipitate the gum. I use the bleached and decolorized gum-lacquer to realize silhouette inks very resistant and very covering and varnishes in solvent phase.

Gross copal resin Which must be moistened This copal was left to moisten with alcohol on an experimental basis for 5 years (result photo on next page)

Copal Resins

The copal resins, where as they are frequently and erroneously referred to in trade as "copal gum", include various types of resins, some recent, others of fossil origin. Copals come from almost all tropical and subtropical countries in the world. The main sources of trade copal come from East Africa, West Africa, the Indies, certain islands of Po-

The copal becomes gradually translucent after being moistened for months or even years, the more you let it moisten the more transparent it becomes.


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THE NATURAL RESINS The copal resin

The trees that produce these types are probably Copaifera guibourtiana, Cyanothryrsus ogea and oblonga Daniella. The copal of Manila is produced in the Philippine islands, but the same type of resin is also found in India, it is found in commerce under the names of Macassar, Pontianak or Copal of Singapore. These are the copals used for the best qualities of copal varnish. The Kauri copal, like the resin from New Zealand and New Caledonia is called: Pin Kauri and Dammara Australis, it is a fossil resin. The finest and best varieties are from East Africa. The South American copal which is the product of Hymenoea species is derived primarily from live trees, commercially known as Demerara Animi, as well as the best qualities which are identical to the best varieties of East Africa. The copal resin varies greatly in appea

rance. It is a hard, fragile, vitreous and semitransparent resin, yellow to red and faceted structures. The main virtue of the copal is its hardness, it forms varnishes with hard surface, able to withstand intensive rubbings. In order to make copal varnishes, the resin must be heated until the destructive decomposition takes place at 260 °C for the Manila copal, approximately 10 to 25% of its weight is lost in the form of water , Of gas and oil, before it becomes soluble in linseed oil and turpentine, in order to incorporate it into varnishes. The copal varnishes are advantageously replaced by varnishes with synthetic resins, however the copal manila is an excellent variety, usable for the manufacture of hard varnish in printing, for the protection of wood, making of varnishes and mediums for the Oilpainting, but care must be taken to plasticize these mixtures with castor oil.

The Baltic amber or Succinct

It is a Upper Eocene plant fossil resin (56 ma to 33.9 Ma), found mainly on the shores of the Baltic Sea, on the coasts of Memel, Königsberg and Danzig, on Which is deposited by the waves. It was discovered amber very recently, in 1996, in France in the Oise, by Gael de Ploëg (Nel et al.1999). It is located near Creil, in the place called "Le Quesnoy" [109]. Amber comes from the fossilization of extinct conifer resin, including Le Pitioxylon Succinifer Krauss. During the fossilization process, the volatile components of the resin evaporate, the remaining hydrocarbons polymerize and harden. The yellow amber is solid, of the color of honey, ranging from light yellow to caramel more or less dark, it presents in pieces of variable sizes, translucent, hard, with conchoidal fracture. Amber is insipid and brittle, it admits a beautiful polish, as in the photo opposite. Amber is mainly constituted by Aweng of 28% succinabietic acid and 70% succinic ester of succinorésinol and 2% of a resin ester of Borneol and succino abietol. The alcohol-soluble succin portion consists mainly of succinic acid abbreviated to C80H120, with a small proportion of esters of bornyl acid and 0.24 to 0.48% of sulfur.

Amber BY Brocken Inaglory via Wikimedia Commons

The alcohol-insoluble succinate portion (70%) is almost entirely composed of succinate of an alcoholic succinoresinol resin. Succinoabietic acid is crystalline, it melts at 148 ° C, and when it melts with potash, gives succinic acid. Succinorésinol is a white amorphous powder soluble in a mixture of alcohol and ether, melting at 275 ° C. (Tschirch and Aweng Arch, Pharm., 232, 660). The heat causes darkening and dehydration of amber. Refractive index: 1.546 Its melting point is between 295 and 395 ° C. Mohs hardness: 2 to 2,5


63

THE NATURAL RESINS When heat is applied to the resin, first succinic acid, water, petroleum and combustible gases are released, this residue is soluble in alcohol, the additional application of heat to the resin Amber oil, which, when the distillation is well conducted, corresponds to 28% of the initial resin, and finally, when the temperature increases at the end of the operation, a yellow wax condenses, Giving an oil of amber color which is a mixture of several hydrocarbons and which constitutes what is used in paint in varnishes. (Baudrimont, J. 1864, 538) It is the most symbolic resin of the painter's craft, because from time immemorial it has been attempted to dissolve it without reaching it completely, it is possible to dissolve 10 to 28% of amber by very long and very diverse means, It is possible to cold dissolve from 10% to 20% amber (previously comminuted and reduced to fine dust by manual means in a mortar) in aspic essence and a portion of toluene, however It is necessary to allow to digest for very long months, to decant, to allow the solvents to evaporate and then to plasticize these mixtures, which makes it possible to obtain a clearer varnish, the addition of glass beads will help dissolve the resin by friction. Its hot dissolution is very problematic and complex, because its final properties have little to do with the initial amber, just like the action of acids on it. Amber formerly used in medicine is now used mainly as ornament, sometimes in photography and in the manufacture of artificial silk. I used experimental amber varnishes in conjunction with clear oil to make a medium to make varnished paints.The use of such a resin is nevertheless anecdotal and the prohibitive price of amber varnishes from trade does not, in my opinion, justify such expenditure.

The genuine Chios mastic varnishes or the Manilla copal are easier to access and they have nothing to envy amber varnishes, especially in terms of use, flexibility and possibilities.

Amber varnish dissolving since 2000

ambre en poudre

Amber powder 2016

Amber powder after 10 years without light


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SYNTHETIC RESINS There are approximately one hundred polar and nonpolar synthetic resins, with various names, allowing the realization 1. Varnish of very high quality. 2. Mastic and adhesives with multiple properties 3. Crystalline and high gloss paints with very high adherence power with multiple features. Plexisol P550/40 et P550/675 or Degalan® P550 It is a soft polymer based on butyl methacrylate in 40% solution in special essence with a distillation range of 100 to 125 °C with 20% aromatic hydrocarbons close to special essence F for P550-40. For the P550 / 675 mixed with Plexigum P 675. It is soluble in esters such as ethyl acetate and amyl acetate, ketones, aromatic hydrocarbons (toluene, xylene), chlorinated hydrocarbons ( Trichlorethylene), aliphatic hydrocarbons: white spirit and Shellsols and in a limited manner in alcohols. Soluble in toluene, xylene, ethylbenzene, trimethyl ethylbenzene in proportions ranging from 1 to 20%.

Characteristics Solvent Solids content Dynamic viscosity Temperature of Glass transition (Tg) Viscosity Index Molecular weight (Mw) Density Flash point Heating temperature Strength required Grubbing up for a Plexisol 5%

MS2-A Résin

Data special essence 100/125 ° C 40% 2800 - 5400 mPas 25°C 35 cm3/ g 65 000 g / mol 0,84 g / cm3 - 5°C 100 à 140°C approximately 2,5 kg

Ketone resins were patented in 1930. MS2-A resin was produced in England in the early 1950s by chemical reduction of a complex mixture of methylation and condensation products formed by reactions involving methyl cyclohexanone, methanol and its derivatives. The resin is obtained by the reaction of the condensation of cyclohexanone and methyl cyclohexanone in alkaline methanol. MS2-A is used to improve the luster, adhesion, hardness and stability of lacquers, enamels, varnishes and specific paints. Its low molecular weight allows excellent solubility in a range of solvents, including aromatic solvents and high-grade aliphatic hydrocarbons such as mineral spirits. It is reproached for its poor UV resistance, which can however be eliminated by the addition of Tinuvin® 292 or any other tinuvin of the range. Plexisol P550

It is a non-polar resin and therefore totally insoluble in water. Compatible with several vinyl, ketone and acrylic resins, including the Paraloid B67 for example. Its films are reversible with acetone and toluene. Plexisol P550 gives glossy, soft and low adhesion films. In addition to the fact that it can be used as a paint binder and as a finishing varnish for works in oil or acrylic diluted 5 to 10% in white spirit. Plexisol P550 is used for example for the manufacture of depolymerizable ceramic layers, for the manufacture of welding wires, for the consolidation of pictorial layers of paintings, for the reattachment of paints on copper, and for the re-weaving of fine textiles. Softening temperature of the film: 54 ° C.

MS2-A resin


65

SYNTHETIC RESINS

Its refractive index of 1.505 provides excellent optical properties. This has allowed its development as an alternative to natural resins in varnishes and other formulations for artistic paintings. MS2-A is a pale yellow resin in pellet form with a sweet camphor odor, but is also pre-dissolved in ethyl acetate.

MS2A varnish In ethyl acetate

Features of Regalrez 1094 Softening Point Typical Properties Acidity Saponification

Données de 90 à 98°C Yellow tone index 2 <1 <1

Density at 21 ° C Flash point Molecular weight Mn

0,99 kg/l 235°C - 455 °F 900 uma 630

MW

900

MW / Mn Mz

1.4 1.370

Refractive index

1.519

°C glass transition

33°C

PROPERTIES OF THE MS2-A RESINE Properties Softening temperature OH VALUE ketones content Acid value Refractive index Density Mw Mn Polydispersibility Molecular weight

Values de 85 à 100°C > 190 mg KOH/g <0,4 groupe / 100g Pratiquement zéro 1,505 1,08 1776- 1929 -1361 769- 460- 488 2,31- 4,2- 2,79 de 400 à 1000

Regalrez 1094

Regalrez 1094 is a hydrocarbon resin produced by polymerization and hydrogenation of pure monomers of hydrocarbons. It is in the form of crystalline tears, very stable to light. It has a low molecular weight. Regalrez ® 1094 is compatible with polyethylene, polypropylene, natural rubber, EPDM, butyl rubber, ethylene-propylene copolymers and isoprene rubber, ethylene-propylene and ethylene butylene intermediate blocks.Regalrez® 1094 can be used with EVA (vinyl acetate) copolymers with less than 20% vinyl acetate, microcrystalline paraffin and polyolefin waxes (release agent and lubricants in plastics processing). To make the Regalrez film more elastic we can add to it 10% of Kraton.

Regalrez 1094

Regalrez 1094 is soluble in aliphatic and aromatic C5 solvents, esters and ketones.It is insoluble in glycol ethers and alcohols. Suitable for zero VOC based systems. Regalrez® 1094 is soluble in tert-butyl acetate and chlorobenzene Tetrafluoride (PCBTC) and tolerates some acetone and/or methyl acetate as a diluent in TBA-based solvent systems ( Tert-butyl alcohol) and/ or parachlorobenzotrifluoride PCBTF. This non-polar resin has been suggested for use in modifying plastics, composing adhesives, paint films, waterproof coatings and poultices.


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SYNTHETIC RESINS It is often used in artworks conservators and painting to create high-quality varnishes in conjunction with Tinuvin 292 and Tinuvin 900 (or Tinuvin® 1130, or Tinuvin® 384 or Tinuvin® 400).

He is compatible with various acrylic and vinyl resins. Paraloid B-72 is an excellent acrylic resin, very resistant to water, alkalis, acids, oils and chemical vapors.

Paraloid B-67 or Acryloid® B-67

It is a thermoplastic solid acrylic resin. Paraloid B-67 is in particular, an alkyd acrylic ester resin designed to have good compatibility with alkyds, oleaginous binders and oleoresinous varnishes. The addition of Paraloid B-67 in alkyds, oils or varnishes produces paint films of very great hardness, improves the desiccation speed, as well as the optical qualities and the hold under the brush creating thixotropic paints. Paraloid. B-67 is the most hydrophobic of Paraloid®. These thermoplastic resins possess excellent resistance to water. Paraloid. B-67 is generally recommended for making all types of paints and especially where the use of water is forbidden, as well as for the production for protective films of metals. It is an excellent medium for non-polar acrylic pigments and paints.. It is soluble in toluene, xylene, methylene chloride, ethyl acetate, mineral spirits, acetone, butanone (methyl ethyl ketone), isopropanol. See above the solubility table. PARALOID B 67

Paraloid B-72 or Acryloid B-72

It is a copolymer based on ethyl methacrylate and methyl methacrylate at 70/30 of medium hardness. It is in the form of transparent solid crystals. Its melting point is between 145 and 150 ° C. Density between 39.8 and 52 It does not have a defined boiling point, however it begins to melt around 70-75 ° C It is soluble in esters such as ethyl acetate and amyl acetate, ketones, aromatic hydrocarbons such as toluene and chlorinated hydrocarbons such as trichlorethylene. Very easily soluble in toluene and acetone. Diluable with xylene, Shellsol A, isopropanol, With alcohols, butyl glycol, methoxypropanol (PM). Insoluble and immiscible in aliphatic hydrocarbons such as methane, ethane and mixtures of turpentine / white spirit.

PARALOID B 72

Paraloid B-72 has a very low reactivity and can therefore be used with a wide range of fluorescent and phosphorescent pigments [43] it can even be applied to objects to be baked. It can be used in combination with other resins to produce paint films and varnishes having a wide variety of characteristics. The films it produces are very elastic and adhere to many surfaces, such as metals, ceramics, etc. .... Paraloid. B-72 is unique for its high tolerance to ethanol, this property allows its use where the use of polar solvents can not be tolerated. Paraloid B-72 is one of the best non-polar resins for the manufacture of UV varnishes with Tinuvins, including 900 and 292, for the protection of metals, in the consolidation of wall paints, PARALOID B 72 en solution wood, glass and Ceramics. Its transparency is also one of its notable qualities.


67

SYNTHETIC RESINS Paraloid B-44

tone), acetone as well as butyl acetate, both of which are good solvents, butyl acetate because of its high flash point and a low level of toxicity. The B-48n can be airor oven-dried. Glass transition temperature: 50 ° C. Refractive index 1.89. Solubility parameters: 9.3 There are other Paraloids, such as Paraloid B-66, ideal for graphic arts and Paraloid B-48n printing inks for engraving and intaglio printing, and Paraloid B-82, a low-cost acrylic resin used to make Lacquers and as a finishing product where a soft resin is required.

It can be dissolved in aromatic hydrocarbons, esters and ketones, but is only partially soluble in solvents such as alcohols and aliphatic hydrocarbons. It is well suited especially for the treatment of metal, copper, zinc, brass, paraloid B-44 the specific treatment of aluminum, and some plastics.

Paraloid B-48n or Acryloid B-48N

It is a copolymer of methyl methacrylate and butyl acrylate which has unique adhesion, excellent toughness, flexibility and durability outdoors. It contains an adhesion initiator that allows fixation on raw or primed metals. The addition of 2% of ethanol can reduce its nebulosity and its stringiness. It is used as protective coating for metals such as: copper, brass, bronze, iron, zinc and aluminum. It is soluble in toluene, xylene, butanone (methyl ethyl ke-

Solubility of PARALOID ™

Acrylic Resins Thermoplastic (The values given are for viscosity, Cps at 25 ° C of a 40% solids solution. (unless otherwise stated)

Correspondence of letters used: -c: Insoluble | D: dispersed | PS: Partially Soluble D. Results when using pure 2B alcohol B-82 is soluble in alcohol / water in various mixtures. E. Viscosity determined at 20% solids. F. Viscosity determined at 30% solids. G. Cloudy solution.

LIST OF POLAROIDS SOLUBILITIES Solvents Alcohol

2B Alcohol Isopropanol N-Butanol Isobutanol N-amyl alcohol Alcohol Diacetone

Chlorinated hydrocarbons

Methylene chloride Carbon tetrachloride Ethylene dichloride Trichloroethylene

Esters

Ethyl acetate N-Propyl acetate N-Butyl acetate Isobutyl acetate Amyl acetate Ethyl-hexyl acetate

Ethers

Dioxane

B-44

B-66

B-67

B-72

B-82

-c 10 000

-c 94e 5 600fg 6 200

-c 2 800 2 500 3 200 3 200 2 300

Dc 130e 3 500

PScd 3 000

2 700 860g 5 500 12 000

850 280e 1 200 7 200

520 20 000 640 2 100

960 280e 1 300 4 800

1 200 6 000f 1 800 3 400

1 800 1 800 2 600 3 100 5 600 -

940 570 875 960 1 110 6 900

240 180 250 240 320 770

500 550g 700 660g 850 -

610 580 630 700 980 -

5 600

880

830

1 300

1 700


68

SYNTHETIC RESINS Mowilith ®30, Mowilith® 50, Mowilith® 60

These are polymers of vinyl acetate which possess properties : 1. Thermoplastics. 2. Good resistance to light 3. Very good transparency. A higher degree of polymerization depending on its concentration, as well as the viscosity of its solutions as well as the film hardness and tear strength.

Mowilith® 30

Viscosity at 20 °C: 22-30 mPas Glass transition temperature (Tg): 30-40 °C Softening point of the film: 105-125 °C

Mowilith® 50

Viscosity at 20 ° C: 100-160 mPas Glass transition temperature (Tg): 35-45 ° C Softening point of the film: 140-160 ° C

Mowilith® 60

Plexigum® PQ 611

It is a binder in particular for odorless and physiologically harmless paints, both for the exterior and the interior, for the preservation of buildings, also for improved insulation systems (polystyrenes). Plexigum® PQ 611 is also used to the production of oil-based printing colors. Density: 1.04 g / cm 3 Density of the powder: approx. 600 g / l Soluble in Shellsol® T, petroleum naphta, esters, ketones, aromatic hydrocarbons (toluene), non-aromatic hydrocarbons (vinyl, ethylene) and aliphatic hydrocarbons (methane, ethane). Its main solvents are aromatic hydrocarbons such as toluene and xylene. It is insoluble in alcohols. Glass transition temperature: approx. 32 ° C Properties of the film, measured on non-pigmented films, dry and without solvent: Pendulum torsion test : 52°. It can be kept cool and dry for 5 years.

Viscosity at 20 ° C: 180-250 mPas Glass transition temperature (Tg): 35-45 °C Softening point of the film: 160-180 ° C The Mowilith are soluble in ethanol supplemented with 5% water, in ethyl acetate, butyl acetate, acetone, butanone (methyl ethyl ketone), methyl isobutyl ketone, toluene. Limited solubility in anhydrous ethanol and xylene.Insoluble in cyclohexane and in petroleum 80/110, ethyl ether (diethyl ether) and water. Areas of application : for bonding paper, textiles, leather, wood, etc. ...

Plexigum® PQ 611

Mowilith® 30

When thick, but low viscosity film is required during processing.

Mowilith® 50 et 60

When thin film, but of high viscosity is required during processing. Ref. Lascaux synthetic resins Datasheets.

Aquazol 200

Mowilith

Aquazol 200 or poly (2-ethyl-2-oxazoline) is A non-ionic and amorphous tertiary polyamide. Chemical Formula: (C5H9NO) n It is a synthetic resin soluble in water. The excellent solubility in water of Aquazol and its thermal stability makes it a preferred substitute for polyvinylpyrrolidone PVP (polyvidone or povidone, an organic polymer synthesized by polymerization of N-vinylpyrrolidone) in high temperature applications.


69

SYNTHETIC RESINS

Aquazol 500 in pieces then dissolved and left in the shade for 3 months: it turns red

Currently, it is used in a variety of pressure sensitive and hot melt adhesives. In addition, it is more accepted in the ceramic industry as a raw earth binder due to its non-ionic nature. It finds other fields of application without being limited to coatings, textile and sizing glass fibers, lubricants and plasticizers.

Propriétés d’Aquazol 200

It is in the form of a yellowish solid Density: 1.14PH of aqueous solutions = neutral Glass transition Tg: 70°C Melting Viscosity at 200 °C: 130 Sec-1 Viscosity in shear rate: 400,000 mPas Refractive index: 1.52 Beginning of degradation:> 380 °C Aquazol® has a wide range of solubility in water and polar organic solvents. SOLUBILITY OF AQUAZOL IN SOME SOLVENTS

SOLUBILITY CALCULATED IN CM3

Solvent

23,4

Range of Solubility

ACEMATT® HK 125

Acrylic matting agent. It is untreated amorphous silicon dioxide with coarse grains precipitated with a heterogeneous particle size distribution. SiO2> 98% PH: 6 (50 g / l at 20 ° C) Density: 2 Kg / l.

Water > 25% in weight

8,9

Toluene

<2% in weight

9,3

Methyl ethyl > 25% in weight ketone

9,7

Methylene > 25% in weight chloride

9.9

Acetone > 25% in weight

12,0

Propylene > 25% in weight Chloride

12,7

Ethanol > 25% in weight

14,5

Methanol > 25% in weight

7,0

N-Pentane

<2% ein weight

"After exposure to UV rays, Aquazol undergoes strong colorimetric variations, yellowing (delta E = 11 and a yellowness index of 14), a decrease in gloss and becomes highly tacky." [99] With titanium white, the effect is lessened because titanium dioxide TiO2 absorbs some of the UV rays. To summarize the paints made with Aquazol must be protected by an anti UV varnish with both Tinuvin 900 and 292 or other Tinuvin. Product

Mass Molecular

Range of Polydispersity

Viscosity

Aquazol® 200

200,000

3–4

18 – 24 mPas

Aquazol® 500

500,000

3–4

60 – 80 mPas

ACEMATT® HK 125

Laropal® K80 (BASF has stopped its manufacture)

Laropal K 80 is a pellet ketone resin, a product of the condensation of cyclohexanone, it is luminous and resists to hydrolysis. It is used to produce all kinds of paint varnishes as a replacement for natural resins, because of its brilliance and excellent resistance to aging, but it eventually turns yellow. Laropal A81 would be much better for the very long term. However its amber color can be sought. Laropal K80 is soluble in traditional solvents such as aromatic hydrocarbons, white spirit, esters, ketones and turpentine, on the contrary it is sparingly soluble in alcohols. It is insoluble in water and methanol. Laropal K 80 is compatible with cellulose nitrate, ethylcellulose, acrylic resins, urea-formaldehyde resins, melamineformaldehyde resins, alkyd resins, epoxy resins, hydrocarbon resins.


70

SYNTHETIC RESINS In fact,Laropal has excellent compatibility. His films are resistant to saponification but do not withstand heat above 80°C. One of its notable qualities is its luminosity. Laropal ® K 80 improves the body, gloss and hardness of paint films and varnishes with which it is mixed. It has a very good ability to bind the pigments, which makes it a very good component of "master pigment mixtures". These "master" blends are used to disperse dyes, pigments and/or additives in paints having different polymer bases, in different materials, such as in printing inks or other homogeneous paint systems. This makes it possible to prepare complex ready-touse paint systems in advance, thus saving considerable time by mixing additives and pigments, the grinding too. It is also used as a consolidant in waxresin mixtures. I am talking about this resin because there may be stocks and you might encounter this type of Laropal K80 varnish resin in the future. left in the dark for 10 years What a pity that BASF stopped producing this resin so practical for the painter, because its dissolution is very fast unlike Laropal A81 which requires 3 times more to be dissolved. Glass transition temperature approx. 49 ° C. Acid number <1. Softening point between 75 and 85 °C. Fortunately I have 1 Kg of this resin that I will use sparingly.

laropal K80

Concentrated lacquer recipe for Laropal K 80 or Laropal A 81

Dissolve in the cold: 25 g of K80 or A 81 laropal in 75 ml of turpentine or Shellsol D40 2 to 5% Shellsol A for Laropal A 81 20 g of glass beads Shake vigorously several times over 24 h and then filter through a stamen or a stocking. Laropal ® A 81 (replaces the Laropal K80) Laropal A 81 is a condensation product of urea and aliphatic aldehydes. It has properties that bring it closer to the Regalrez 1094. Laropal A 81 is luminous, very resistant to yellowing, soluble in the solvents of paints such as alcohols, esters, ketones and aromatic hydrocarbons such as xylene. Limited solubility in aliphatic hydrocarbons such as ethane, isobutane and acetylene. Its solutions tend to separate at temperatures below 15 °C. The addition of 2 to 5% of an aromatic solvent such as Solvesso 100 produces stable solutions.

Laropal A 81 pellets

Laropal A81 can be stabilized with Tinuvin 292. Laropal A 81 is compatible with cellulose nitrate, acrylic resins, urea-formaldehyde resins, melamineformaldehyde resins, alkyd resins, epoxy resins, Hydrocarbons. Laropal A 81 is suitable as a grinding resin because of its high compatibility and the low viscosity of its solutions, its high pigment binding capacity and high transparency. Laropal A 81 can be used for the production of non-polar pigment pastes with a high pigment content, due to its good pigment wetting qualities and the very low viscosity of its solutions, which makes it the same as Laropal K 80, a very good component of "master pigment mixtures". Laropal ® A 81 is very stable to heat, it does not fade and can be used in ceramic cooking finishes, it emits no odor. Used as a modification component in the production of alkyd resin, it allows the partial replacement of up to 20% solids on the whole of the parent material.


71

SYNTHETIC RESINS Laropal A 81 improves the roundness, gloss and hardness of paint films. It takes 3 hours to dissolve Laropal A81 directly in hot waxes where it took 10 minutes with the Laropal K80. It greatly improves the adhesion of paint systems to all types of substrates. Glass transition temperature approx. 57 ° C Acid value ≤ 3 mg KOH/g Softening point between 80 and 95 ° C. 2 to 5% xylene, toluene or shellsol A must first be added to the cold to dissolve or moisten 48 hours and shake the mixture vigorously. Laropal A81 serves mainly as a binder for pigments and for retouching, to make high-performance varnishes and to paint hotmelt road markings on the bitumen. How to dissolve Laropal A81varnish and lacquers when they age ? Response : With a mixture of 70% acetone and 30% toluene.

proves gloss, hardness, body, adhesion and resistance to yellowing. It is a resin of very high quality. Due to its good wetting of the pigments and a very low solution viscosity, Laropal A 101 can be used for the manufacture of pigment pastes with a high pigment content. Laropal ® A 101 is not soluble in aliphatic hydrocarbons and therefore is particularly suitable for films resistant to mineral oils. It is suitable for resin grinding due to a wide range of compatibility and solubility, low viscosities of the solution, high pigment bonding capacity and high transparency. Due to its relatively low solvent retention, it only leads to a slight increase in the drying time of the varnishes (for example with nitrocellulose). Laropal® A 101 is excellent for indoor and outdoor paints, it is a very good adjuvant of paints for those who want glossy films, non-yellowing and very resistant, so to make synthetic paints very perennial.

Laropal A 101

Laropal ® A101 is a condensed product from urea and aliphatic aldehydes. It is mainly an aldehyde resin for the dispersion of pigments: it promotes wetting and it has good elasticity, good hardness and excellent adhesion. Physical characteristics of Laropal A 101: Light yellow pellets Low odor Melting: 95-110 ° C Density: 1.1 Kg / l (20 ° C) (DIN 53217) Bulk density: 600 - 700 kg / m3 Solubility in water: insoluble Acid number = 3 mg KOH / g Iodine color number = 5 Density at 20 ° C ~ 1.1 g / cm³ or 9.26 lb / gal Softening range 95-110 ° C Temperature Tg ~ 73 ° C, 163 ° F Hydroxyl value ~ 35 mg KOH / g Saponification value ~ 62 mg KOH / g Laropal A 101 is soluble in alcohols, esters, ketones and aromatic hydrocarbons such as toluene and xylene. It is insoluble in aliphatic hydrocarbons such as methane CH4, propane C3H8, ethane C2H6, isobutane C4H10, acetylene C2H2. Laropal® A 101 is compatible with nitrocellulose, CAB resins (A thermoplastic polymer composed of cellulose esterified with both acetic acid and butyric acid. Cellulose acetate butyrate or CAB became a commercial product in 1938 ), Chlorinated rubber, vinyl copolymers, acrylic resins, urea-formaldehyde resins, melamine-formaldehyde resins, alkyd resins, epoxy resins and hydrocarbon resins. Limited compatibility with ethylcellulose. Because of its excellent solubility and compatibility, Laropal ® A 101 can be used in many paint formulation systems. Depending on the application, it im-

Laropal A 101

Tinuvin 292 Ciba SC [60]

Tinuvin® 292 is a transparent liquid. The active substance in Tinuvin 292 is a mixture of Bis (1,2,2,6,6 - pentamethyl - 4 - piperidyl) sebacate of molecular weight: 509 and Methyl 1,2,2,6,6 - pentamethyl - 4 - piperidyl sebacate of molecular weight: 370. Chemical Formula: C30H54N2O4 It is an amine stabilizer specially developed for paint systems, it is not a UV absorber. It extends the life of coatings by minimizing paint defects such as cracks and loss of gloss. The resistance of the paint films to the aggressive air agents can be considerably improved by the use of a combination of Tinuvin® 292 and UV absorber Tinuvin® 1130, Tinuvin® 384, Tinuvin® 928, Tinuvin ® 400 or Tinuvin® 900. These synergistic combinations in automotive paints, for example, provide superior protection against gloss reduction, cracking, blistering, delamination and


72

SYNTHETIC RESINS shade changes, so imagine what they can bring to artistic paints. ts range of applications goes from alkyd and polyurethane paints to oils, acrylic water, phenolic, vinyl and acrylic paints. Test the stability of the mixture. Optimum protection is obtained by mixing tinuvin 292 with Tinuvin anti-U.V like Tinuvin 900 in the later layers of the work or by incorporating it into a pure varnish. Not miscible with water but its dispersion in water can be facilitated by diluting it with a water-miscible solvent such as butylcarbitol. Specific gravity at 20 °C = 0.9905 g / cm3 Dynamic viscosity at 20 °C = 400 mPas Boiling point = 585.478 °C Flash point = 307.886 °C SOLUBILITY AT 20°C for 100 G OF SOLUTION Butyl carbitol > 50 Butanol > 50 Butyl acetate > 50 Depanol® J > 50 Ethyl glycol > 50 Methoxypropyl acetate > 50 Methyl ethyl ketone > 50 Solvesso® 100 > 50 ; Solvesso® 150 > 50 ; Xylene > 50 ; Hexanediol > 50 Triacrylate triethyl-ol-pro> 50 pane Recommended dosages in binders = 1.0 to 3.0% Tinuvin® 292 improves paint systems. Tinuvin 292 liquid Tinuvin 292 liquid

For UV-resistant paints and varnishes

Between 0.5 and 3.0% of Tinuvin® 292 If the resin is natural up to 3% If the resin is synthetic up to 2%. 1.0 to 3% Tinuvin® 900 or other. Tinuvin is calculated on the weight of solids.

Recipe for Tinuvin Varnish with Mastic Mastic of Chios = 25 g or 25% Tinuvin 292 = 3 g, ie 3% Shellsol D40 = 74 g, ie 74%


73

SYNTHETIC RESINS Recipe for Tinuvin Varnish in Dammar

Dammar Resin = 20 g Tinuvin 292 = 3 g Tinuvin 900 or 400 or 1130 = 3 g Shellsol D40 = 74 g Always wear gloves and goggles when using Tinuvin® Studies have demonstrated the stability of varnishes to which tinuvin 292 has been added; After 6000 hours of artificial aging to light, they did not turn yellow.

Tinuvin 900 Or Tinuvin Liquid 400 or Tinuvin Liquid 1130

Tinuvin® 900, 400 and 1130 are UV-refractors of the class of hydroxyphenyl-benzotriazole, developed especially for the manufacture of varnishes for paints. Chemical Formula of Tinuvin 900: C30H29N3O Composition Chemical Tinuvin 900: 2- [2-hydroxy-3,5-di (1,1-dimethylbenyl) phenyl] -2H-benzotriazole. Molecular Weight: 447.6 Melting point: 137-141 ° C Specific gravity: 1.22 g / cm3 at 20 ° C Thanks to its extended UV refraction, Tinuvin® provides effective light protection. Tinuvin 900

Solubility at 20 ° C in solution per gram Of Tinuvin 900 per 100 grams of solvent Butyl carbitol 0.2 Butanol 0.3 Butyl acetate 4.5 Depanol® J 2 Ethyl glycol 1 Methoxy propyl acetate 22 Methylethyl ketone 5.5 Solvesso® 100 5 Solvesso® 150 5 Xylene 10 Water < 0.01

Tinuvin® are high performance resins, very XXIst.

Wear gloves, a mask and, if possible, goggles when handling Tinuvin® in its liquid form. Prefer the vernissages outdoors in summer if you can. If by unfortunate chance there was contact with the eyes, wash thoroughly with running water for at least 15 minutes holding the eyelids apart.

Xylene appears to be the best solvent.

UV varnish with Tinuvin 900 and 292

The concentration of Tinuvin is: 1.0 to 3.0% of Tinuvin 900, 400, or 1130 0.5 to 3% Tinuvin® 292 depending on resin In 5 to 15% of xylene and then 60% of Shelsoll D40. Either about 1 to 3 g of each Tinuvin per 75 g of solvent. It is preferable to make tests beforehand in order to ascertain whether the substrate and the paints do not react with the varnish if necessary.

Tinuvin 1130

Conclusion

There are also organic chemicals such as cinnamic acid C9H8O2 and its esters, used as antioxidant substances found in Peruvian balm and Tolu balm or benzophenone derivatives which absorb ultraviolet light and thus protect products from discoloration or bleaching. They can be very practical in oil-in-water emulsions, but also in order to store liquid or pasty materials and thus protect them from UVA rays.


74

NATURAL GUMS Natural Gums

Natural gums are materials produced and collected from different trees and plants, algae or by reactions of microorganisms on glucoses and mineral salts which form with water a kind of jelly or a more or less viscous liquid with name of "mucilage". They are used in the preparation of binders for paints and aqueous techniques, such as watercolor, gouache, dry pastel, and also as thickeners, gelling agents and stabilizers for emulsions, etc.... A preservative must always be added such as camphor or sodium benzoate. (See preservatives). The term "gum" should designate only water-soluble materials (the right words is diluted) as opposed to the term "resin" which should designate only substances soluble in non-polar solvents. The process for producing gums consists by preparation of flour by mechanical means. Another method conducted by hot solubilization of the raw material, followed by filtration to remove insoluble materials. The clarified solution is precipitated by isopropyl alcohol, the precipitate is pressed, dried, ground and then sieved.

composed of collagen, elastic tissue and reticulated fibers), which are by desiccation reduced to a very small volume. Formerly before the trade in gum arabic, fruit tree gums were the only ones used [7]. They have the advantage of being very easy to obtain and of a simple use, it is sufficient to finely grind the dried gums and then to macerate them in their own volume of distilled water or boiled water then decanted, And to add another volume of water and then to filter through a cheesecloth to constitute a binder which can be used in all aqueous techniques, miscible with all pigments. Although the color of the gum is dark, it does not change the hue of the pigments.

Left Cherry gum dissolved in water. On the right, very light apricot gum. Both dissolved by mechanochemistry.

The Arabic Gum Cherry and apricot gums

The Country Gum or Gum from France, cherry, apricot, plum and fruit trees

Gummi Nostras, officinalis. It comes from the natural exudation of fruit trees in the drupaceae section of the rosaceae family, such as apricot, cherry and plum trees, in this case, but gums can be harvested from other trees fruit trees such as peach, apple, pear, etc.[6] The gum oozes from the old trunks in the form of a colorless liquid which hardens in the air and then becomes colored in reddish brown more or less dark following the gum. The gum of country macerated in water provides a mucilage which is not a true dissolution, it is the swelling of collagen fibers (loose connection fabric,

Gum arabic is produced by many species of Acacia trees of the family Mimosaceae, originating in Africa and Sudan. Nearly 900 species of Acacia are able to provide gum arabic, however, according to the Codex Alimentarius definition, only gums produced by Acacia Senegal and Acacia Seyal have the official denomination of "gum arabic". The best known varieties are Acacia Senegal, Acacia Laeta and Acacia Seyal. The commerce of gum begins first in Egypt because the Egyptians knew it and used it (2650 BC) to ensure the cohesion of the bandages of the mummies. Gum arabic was introduced into Europe in the Middle Ages via the ports of Arabia, from which its named, and from the ports controlled by the Turkish Empire, the gum arrived in Europe under the name of "Turkish gum" then the illuminators used it [8]. The natives of Mauritania feed with gum arabic.


75

NATURAL GUMS The largest production of gum arabic is concentrated in Africa, giving it its nickname of gum Senegal, whose 80% of the production comes from Acacia Senegal (Sudan), the rest is divided half between Acacia Laeta and Acacia Seyal. Gum arabic, is a polysaccharide more commonly known as "Sugar" which contains calcium, potassium and magnesium : it is extracted from the exudation of Acacia Senegal.

TYPICAL COMPOSITION OF GUM ARABIC

Oxygen

50.84

Carbon

42.23

Hydrogen

6.93

Total

100

Acacia laeta Burkina Fasso par Marco Schmidt

Commercial Arabic gum in powder

Aqueous gum arabic solutions may be slightly acidic, check them with a pH meter. Gum arabic is soluble in water, insoluble in alcohol and incompatible with it, as well as with lead salts, mineral acids, ferric, cupric and oxalic acids. The strong acids decompose it. Gum arabic is classified as an E414 food additive in the thickener family.

Arabic gum in pieces very great quality

It's an all-purpose gum. It has been used in the "Enluminure" technique for a very long time. Gum arabic mixes well with albumin as well as with skin glue, for specific painting techniques. It was also the main ingredient of the white glue of school children. In the form of an aqueous solution, it decomposes very rapidly under the effect of oxygen, so we must add a preservative such as sodium benzoate or a little camphor. The ideal would be to prepare well in advance and leave the solutions of pure gum arabic to sediment, because I have noticed that a brownish sediment deposited at the bottom of the vial after a few weeks, Transfer the upper part into a new flask. Gum arabic is a stabilizing adjuvant for emulsions and temperas. Through the use of gum arabic solutions in water, the oil can be miscible with water to form oil-in-water type emulsions which behave as aqueous binders. The gum arabic in solution is used up to 20 times its weight in water, for the preparation of binders for gouache and watercolor. I also use it in the formulation of greasy varnish or overprint varnish, to regulate their transparencies and their rheological properties. Density: 1.291.39 Kg/liter. Note that there is no impurities, this it's the advantage of using the version in pieces, she is cleaner than the commercial powdered


76

NATURAL GUMS Gum Traganth or Gum tragacanth

Also named Traganthe, gummi tragacantha. It is known since the 3rd century BC. J.-C., Theophraste describes it. It is extracted from the natural exudation of the dried sap of about twenty species of plants of the Astracantha genus of leguminous : 1. Astragalus gossypinus 2. Astragalus echidnaeformis 3. Astragalus Gummifer Lab growing in Asia 4. Astragalus Microcephalus which grows in Turkey and Iran, main place of production. Incisions are made in the trunk of the shrubs then the gum flows out in the form of twisted filaments, odorless, white or yellowish translucent ribbons with a horn-like callus-like texture, which has earned it the name "Goat's spine" by extension "goat's horn", whence Tragacanthe which means tragos = Goat and akantha in Greek = spine (horn). Tragacanthum gum is a mixture of polysaccharides consisting of tragacanthin completely water-soluble and bassorin, tragacanthic acid, insoluble in water, but which swells heavily, making it possible to obtain high-viscosity gels from aqueous solutions at 2%. It is soluble in 70% hot water and to some extent in alcohols, which is used to moisten the gum before dissolved her in water.

Natural and raw adragnate gum from the Lion of Brussels. It must be ground and then dissolved 100 g per liter of water

The gum dissolves and forms a mucilaginous liquid with boiling water. The viscosity of the tragacanth solution at 2% can reach 3600 mPas. Solid camphor is added to cold solutions of tragacanth as a neutral preservative. We use tragacanth gum to make dry pastels sticks, watercolor in godets or pans, thick gouache, but also to prepare the fabrics, leathers, skins and smooth the vellum because the gum has a great rigidity when dried. The thixotropic qualities of gum tragacanth can be used in tempering emulsions techniques, hide glue paints and other glues. The gum tragacanth is plasticized with honey or glycerine or with antifoaming agent. It is used in pharmacy and pastry as a food additive declared E413 (authorized in France).

100 g of natural tragacanth in 1 liter of distilled water.


77

NATURAL GUMS The Ammoniac Gum

It is a plant originally from Asia, belonging to the Apiaceae family which can reach up to 2.5 m in height, which grows in Iran, India, Afghanistan and Pakistan. The plant contains up to 95% oil containing about thirty components rich in sesquiterpenes, the most significant of which are sesquiterpene hydrocarbons (up to 68.57%) of δ-cadinene of formula = C15H24 (16.24%) and up to To 15% of oxygen-containing sesquiterpenes as well as α-Pinene, limonene, camphene, etc. ... The gum ammonia is the sap extracted from the Dorema ammoniacum Don which is a gum-resin found in the cavities of the stems. It often naturally exudes from holes caused by beetles. It is used in "enluminure" as a mordant for the laying of gold leaf, The resin resembles a milky gum in the form of agglomerates or small tears, which can vary in size from that of a peanut to that of a nut, often associated with many impurities. The gum ammonia is hard, fragile and brittle which melts at ~ 54 ° C, and which becomes flexible by manipulating it in the hand. The alkalis form a cloudy solution with it. Nitric acid converts it into a yellow substance, soluble in alcohol and hot water, which can dye fabrics of a very fine shade of yellow, which is not affected by chlorine. The gum is partially dissolved by water, forming with it a white emulsion, which precipitates a resinous part by sedimentation, leaving a clear liquid to appear clearly. The alcohol dissolves more than half the gum, the remainder being its resin, which remains insoluble in alcohol. The part of the soluble white resin is precipitated by the addition of water to the remaining alcoholic solution. The gum ammonia has a slight odor, due to the presence of a small amount of essential oil. Ammonia [not to be confused with ammonia, an alkali (NH4) 2CO3)] is constituted by :

When the gum has soaked the liquid, we must express the solution then mix everything and pass through a cheesecloth. If the mixture is too thick, add a little gum arabic solution and a few drops of glycerine and a conservative. This solution of ammonia gum is applied with a brush at the place where gold leaves are to be applied, but they can not be browned. Ammoniac gum is also used in admixture with mastic resin or fish glue; This makes it possible to make a solid adhesive which serves to adhere gold leaves, to stick precious stones together and to repair the porcelain.

Dorema ammoniacum

Gum between 18 et 28% Resin between 56 et 68% Essential oil between 1,5 et 6% CHARACTERISTICS OF AMMONIAC Density between 1,190 et 1,210 Ashes between 0,79 et 447% Acid number between 69 et 80 Ester value between 19 et 38 The gum resin is pressed into blocks and then ground into powder. To use the gum, it must be digested for 12 hours. It must be completely covered with 1 cm of water with 5 drops of sodium benzoate.

ammoniac Gum


78

NATURAL GUMS Dextrin and Starch

The dextrin (E1400) consists of D-glucose, which contains 6 carbon atoms, 12 hydrogen atoms and 6 oxygen atoms which form a structure which has an intermediate chain length. Chemical Formula of Dextrin (C6H10O5) n • xH2O. For the synthetic variety, starch is heated with hydrochloric acid (E507), orthophosphoric acid (E338) or sulfuric acid (E513), which has the effect of fragmenting the starch , So it swells more quickly. To synthesize dextrin, starch of corn, barley, rice, wheat or soya is heated at 180 ° C. for 2 to 3 hours. These are substances classified as food additives E1402 for starch treated with alkalis, E1401 for starch treated with acids and E1403 for starch bleached using hydrogen peroxide. Originally, the starch most used was obtained from potato starch in the form of a white to yellow powder, which dissolves very well in water but little in alcohol. It is also made with starch of wheat, barley, corn, rice or soy. Hydrolysed plant proteins are decomposed into amino acids by a chemical process (acid or alkaline hydrolysis) or enzymatic and are currently used as binder for paint as a replacement for casein in certain ecological paints but also for promote low VOC paints (see glossary).

pure than that synthesized. The dextrin or starch of potato, wheat or corn is also a food additive under the number E1400. The dextrin E1400 is used to make adhesive (for example for bonding stamps, leather, photographic articles). Starch is used in artistic painting as a thickening agent and as a substitute for arabic and tragacanth gum. In industry, it is used to thicken colored printing inks, and also to starch wallpaper, it is also used in art restorers. Dextrin is comparable to gum Tragacanth in its use, it has the same film-forming and thixotropic characteristics. These amidon's gums are all thickeners, neutral gelling agents in aqueous paints, which can also be used as aqueous binders adjuvants.

The Guar Gum

It is extracted from a plant, the seed of an Indian legume, a bean, cyamopsis tetragonoloba, an annual plant of the Fabaceae family. Guar gum E412 is a virtually odorless, white to yellowish powder.

Extra pure Dextrin

Starch Glue Recipe

50 g of dextrin mixed with 100 ml of water 5 g of potassium hydroxide known as caustic potash KOH or wood ash dissolved in 200 cl of water Mix the two solutions to obtain a glue. It is a method of preparation applicable to other gums, to wet the tragacanth gum we can uses alcohol, although personally most of the time I prefer to let the gums wet with water in a natural way. Potash may also be collected from wood ash, but it is less

Guar gum

It is comparable to the Tragacanth gum in its use, it has the same film-forming and thixotropic characteristics.

Tara or Caroube Gum from Peru

Gum Tara or Caroube from Peru It is extracted from the seed of a South American tree: Caesalpinia Spinosa which appears as a white to yellow powder, almost odorless. Tara gum may contain resin acids and their esters, terpenes, as well as pro-


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NATURAL GUMS ducts resulting from the oxidation or polymerization of these terpenes. It is soluble in water at low temperature, at less than 50 °C and in ethanol. Tara gum is sensitive to acidic pH. It is a food additive under the denomination E417 (authorized in France). Tara gum is used to thicken and stabilize emulsions and gels by providing a structured effect. This polysaccharide of nonionic structure instantly hydrates in water and can be used both hot and cold. Tara gum is recommended for formulations of medium to thick consistency, it requires to be passed at cold with a mixer then left to rest to allow it to thicken. Use: from 0.30 to 1% as stabilizer and from 1 to 2%, to form gels.

Agar is produced in China, Ceylon, Bengal and Japan, where it was discovered in 1658. Insoluble in cold water, soluble in boiling water.

Agar agar

Tara gum powder and mixed with water: note its brown color

Agar Agar gum

It comes from various red algae of the Rhodophyceae class: Gracilaria Gelidium. Agar is a dried hydrophilic colloidal substance extracted from certain marine algae. Their active ingredient is a galactose polymer, more particularly consisting of very weakly sulfated (2 to 4%) and 3,6-anhydro-galactose galactose units. It is a polysaccharide consisting mainly of D- and Lgalactose units. About every tenth of D-galactopyranose units contain a sulfuric ester group. Cations of calcium, magnesium, potassium or sodium are also associated with the polysaccharide. The algae are cut, boiled and filtered and then mixed with a solution of ethanol and water to obtain an agar precipitate which is then dried.

On cooling, it gives thermoreversible, firm and brittle gels. Gel threshold reached with 0.25%. It is a food additive under the name E406 (authorized in France). [9]

recipe of Agar gel

Prepare a 1.0% solution of agar with boiling water in a container which is then put in a water bath at 30 ° C for 15 min. A firm, strong gel is formed. In water at 70 ° C for 1 h, the gel does not melt. When heated to a temperature above 95 ° C, the gel is liquefied and becomes a clear solution.

Test to distinguish agar from

Alginate, gum arabic, gum ghatti, gum karaya, pectin and gum tragacanth: A solution at 0.5% of the sample gives a precipitate with half its volume of a hot solution (40.°C.) of ammonium sulphate at 40% in solution.

The bacteriological tests demonstrate

Scheme de 3,6-anhydro galactose

Total number of plaques : Not more than 5000 colonies per gram. Yeasts and molds : Not more than 500 colonies per gram. Coliforms : negative to test. Salmonella bacteria : negative to test. Ref. : Technical sheet available online here

http://www.-pigmente.com/media/pdf/63470e.pdf


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NATURAL GUMS Other Algae Gums Carrageenans E407

These are marine algae growing mainly on continental slopes. In France, Brittany 'bretagne) is the first producer. The carrageenans are divided into 4 main groups, divided into two functional groups: 1 / gelling carrageenans 2 / thickening carrageenans

carrageenans gum

There are other seaweed gums like :

Furcellaran

Which is an extract of other red algae Furcellaria fastigiata of the Furcellariaceae family of the Gigartinales order.

Alginates

They are extracts of brown algae, laminaria or fucus of the class Phaeophycaeae. We obtained by an alkaline solution, a viscous liquid of a brown alga of the laminaria species. Chemical Formula (C6H8O6) n. The alginates make it possible to form hard and thermostable gels. Alginates are used as thickeners, gelling agents, emulsifiers and stabilizers. It is possible to obtain a propane-1,2-diol alginate E405, a particular ester of alginic acid, which is a foam stabilizer. To obtain the gum it is necessary to clean and then cut the algae, to make them macerate in a diluted acid to demineralize them. The result is ground in the presence of an alkali in order to neutralize the alginic acid to solubilize it in the form of a salt. The

precipitated extract is washed, pressed and wringed, then finally neutralized, dried and ground to the desired size. Ask your supplier for the technical data sheets of these gums if you want to use them, but overall they behave like other gums.

The Xanthan Gum

It is a gum of microorganic origin : The Xanthonomas Campestrisla. Xanthan rapidly thickens with aqueous solutions even at very low doses (1 to 3 g per liter). It is so thick that it quickly constitutes a material that resembles a jelly. It stabilizes the emulsions and all the rebellious mixtures which are sedimented (mixtures of minerals and salts), it is even more viscous in the presence of Guar gum and it gels firmly with the gum Tara. The xanthan gum is obtained by the fermentation action of a bacterium Xanthomonas campestris on a hydrocarbon substrate (eg corn starch, glucose, sucrose). The mixture is purified with ethanol or isopropanol and then dried and ground. Sodium, potassium or calcium neutral salts are also produced for commercial purposes. Tank culture converts glucose and mineral salts into xanthan, which have a structure similar to cellulose, only their lateral links are different, they include acid functions, acetylated hydroxide functions, and others acetalised by pyruvic acid. Of very complex composition, the xanthan molecule has two parts : Inside, a molecule of glucan, and several external chains. Glucan is a particular molecule of polysaccharide. The polysaccharide molecule is composed of several molecules of monosaccharides, attached by osidic bonds, covalent bonds. This bond is formed when two sugars meet, losing a molecule of water. This reaction is called the condensation reaction. The formation of the bond produces water, which is not found in the general formula of a polysaccharide: Cn (H2O) n -1, hence the presence of (n-1). This main structure is surrounded by several chains which in particular allow the stability of xanthan in an acidic, alkaline or enriched in enzymes medium. The xanthan gum is nonionic, very avid for water, forming colloidal solutions that are very stable and hardly sensitive to temperature variations. Since 1964, xanthan gum has successfully replaced fruit tree gums, which are less easy to extract. It is considered as a food additive under the denomination E415 (authorized in France). She finds multiple way in painting and can be used as gum tragacanth. Its pH varies from 6 to 8 in 1% aqueous solution.


NATURAL GUMS

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Conclusion

Here is another example of a very modern material of the 21st century. Xanthan gum is a very versatile gum, despite the reproach that can be made of it with a marked effect to fluff. Gum tara, favored by those who often make emulsions. The most versatile in my opinion is gum tragacanth, but its prohibitive price, targets it to small amounts of paint, pastel or emulsion.Xanthan gum is a " minute gum", she is simple to use and forms instantly with water, flexible gels immediately usable (like the Laponite). xanthan gum pH 6.5 13 g for 400 Ml of water

Xanthan gum powder

Recipe for Gum Xanthane : 2 grams of xanthan gum mixed with 10 grams of water, immediately give a gel with

good film-forming qualities. The gel formed is not brittle. However, it is necessary to add a preservative like sodium benzoate, because in just 2 days the xanthan gum already begins to mold.

Gums and glues for water paints:

from left to right: Apricot Gum, Fish Glue, Parchment Glue, Skin Glue, Albumin, Tylose MH300, Gum Tragacanth and Gum Arabic. You have here a panel with gums and glues that allows you to make all kinds of paints such as watercolor, gouache, Enluminure, tempera, etc ...


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ANIMAL GLUES THERE ARE 4 FAMILIES OF GLUES AND 2 TYPES OF ANIMAL GLUES Skin glues are derived from materials present in the skin and the connective tissues associated with the skin. As a group, skin adhesives are the strongest and most versatile of animal adhesives given their wide application. The glues are generally in the form of plates, beads, flakes or in powder form. The average moisture content of the animal glue is 11 to 14% (loss of weight), subject to slight variations due to changes in relative humidity. An ash content of 3.00 to 4.50% is considered normal. In aqueous solution, the adhesives skins are estimated of neutral. The pH range of skin adhesives is between 6.4 and 7.4. The bone glues are slightly more acidic, their pH range is between 5.8 and 6.2. The specific weight of the dried animal glue is about 1.27. Recipe in detail of this parchment glue in my third book: "Colorants inks & pigments of plants" © 2018 David Damour

1.Skins or Hides glues

From the skin and connective tissues of rabbit and / or hare (but also goat, sheep, lamb) or veal for parchment glue. Currently, real rabbit skin glue are made in Italy, Germany and Spain. It is very easy to make with parchment, parings of leather or rough gloves, these are more, the best glues. Among the clearest glues are those of calf parchment, which are also the finest.

Skin glue recipe

We take pieces of rawhide or parchment - (we must treat the fresh skins with lime) - boiled with 18 times their weight in water, per 100 grams of leather, 1.8 liter Of water, stirred constantly with a wooden spatula, and reduced by half. It is allowed to cool a little and then the liquid is poured on wooden boards or in molds. After cooling, the squares obtained are cut out, protected from moisture. It is possible to add as a preservative a tiny amount of camphor in the glue still liquid and tepid. As an experiment, I have kept for 20 years a glue of skin with a little alum, and simply adding a nut of camphor. See photo at bottom of page.

Genuine rabbit skin glue

Parchment glue made by cooking scraps between 2 and 4 hours with 22 times their weight in water; then we pour on plastic lids © 2018 David Damour

Adhesives Precaution of use 1. Always use clean equipment. 2. Weigh the glue and water separately. 3. Soak the glue in clean cold water beforehand. 4. Pour the dry glue into the water. 5. Prepare separate glue lots. 6. Once the glue has inflated, it will be necessary to cook the whole glue in a single time and not to dissociate it, in order to preserve the ratio glue / water 7. Always use a gentle heat (<45 ° C), never boil or simmer glue.

2.Bone Glues and Gelatin

They come from the collagen present in the bone matter of beef and pork. All the current commercial adhesives are bone glues apart from the glue of rabbit skin and that of hare. The bone glue is treated from clean and dry bones that have been degreased before the treatment for glue. As a group, bone glues, although not as versatile as skin glues, are used when a lower grade glue is acceptable. Skin glue in solution for 20 years.

Its sticky power, however, has diminished.


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ANIMAL GLUES 2- Gelatins

Some gelatins are made with rabbit skins, they are called technical gelatin plates. With beef skin, the glue comes in powder and that of pig skins is in sheets. They are of limited interest in relation to true skin adhesives. Bone glues are currently manufactured in China, gelatin in Spain and Italy. We can however realize bone glue with 1 kg of clippings bone in 4 liters of water, to boil, until reduction of one third of liquid, then to flow.

Colle de peau en grésils

2. Recipe for casein from Rians® Fresh Cheese

The natural casein is made with 50 grams of white cheese, mixed with 10 g of slaked lime, thus immediately transforming it into calcium caseinate or with 15 g of ammonia transforming it into ammonium caseinate,Add 2 to 3 volumes of water. It is stored in a full and clogged bottle, although it is preferable to use it very quickly, otherwise add a preservative such as camphor which gives it a more pleasant odor or 20 drops of sodium benzoate because this glue does not does not preserve at all, it emits a characteristic odor after a few days, or even a few hours in hot weather. The casein solubilized by lime is much more sticky than when it is solubilized by borax, which makes it possible to reduce the quantity of fillers, in particular kaolin and talc. Final Ph of the glue ~ 12.6

Plaque de Gélatine

3. Fresh Cheese Glue known as "Casein"

Casein is the main protein in milk of mammals, it is in part coagulate milk, it is called the curd, physical condition after the coagulation of milk like curd. Casein should not be confused with pure milk, since the presence of lactose and other soluble products in the latter makes it a very unstable product for paints.

Freh skimmed milk

chaux-eteinte

1.Recipe for extracting the curd from fresh skimmed milk and then making the glue 1.Heat without boiling 1 liter of skim milk 2. Add an acid, 5 teaspoons of white vinegar to the milk, gently stirring until the milk separates into curds which form small sticky and solid pieces and on the other side, whey, which is in the form of a clear liquid 3. Filter through a sieve to separate the whey from the lactosérum to collect the curds 4. In a plastic container or clean glass, add an alkali : 15 grams of ammonia dissolved in a little water or slaked lime. You should now get a sticky white substance called casein that has just been extracted from the milk protein, however it is not as pure as the commercial one. This is the casein base binder, which can be diluted with pure water.

Slaked lime

COMPOSITION OF COMMERCIAL CASEIN

Proteins

82 at 84%

Protein, dry weight

92 at 94%

Lactose

0,5 at 0,85%

Ash content

2.3 at 2.8%

Fat (SBR method)

1.8 at 2.3%

Humidity

11 at 12%

PH

4,1 at 5,1

Free acid n / 10 NaOH

8.8 at 9.6 ccm


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ANIMAL GLUES 3.Preparation of commercial casein

Powdered casein is prepared by swelling 50 grams of casein in 150 ml of hot water to which is added 15 g of ammonia dissolved in a little water. It is necessary to stir constantly when introducing the alkali or to pass to the mixer, the liquid foam strongly, the casein dissolves, we add again: 150 ml of water, which makes it possible to obtain a base solution, in which it is necessary to add 5 drops of glycerin to plasticize it for flexible supports + defoamer

It is a natural product that is obtained by baking fish skins, followed by evaporation. It is very viscous at room temperature and reaches a rubber-like consistency. This fish glue can be made fluid by heating it without losing quality.

Glycerin

Ammonia

4.Fish Glues or Ichthyocolle

Sturgeon glue is extracted from swim bladders from various fish skins. It is made in Russia for the variety "Salianski" and in Canada for liquid glue. The authentic Swiss sturgeon glue is the best quality available in the world. It is made of fresh bladders of the sturgeon (species of origin: Acipenseridae). The bladders are cut in length, put in hot water to get rid of any foreign element, and then suspended in order to dry them. The largest amount of native collagen is contained in the bladder caviar fish, which is qualitatively the best variety. This quality is referred to as "Salianski sturgeon glue". Sturgeon glue has been used for a long time by Russian art restorers, as adhesive and for consolidation. The sturgeon glue has a higher adhesive power, but a lower viscosity than animal glues, such as gelatin or glue of rabbit skin. It is an exceptional glue of very high purity, to be reserved for fine works, as for laying gold and precious plasters (and also because of its prohibitive price: 450 € / kg). There is fish glue in transparent flakes, in plates, as well as liquid variety.

Common astarch glue nd 25% fish glue in water at right

Clear sturgeon glue and purified into fine sticks

Unfiltered Saliansky fish glue, here pure just dissolved


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VEGETABLE GLUES Among the vegetable glues, there are all the gums which can serve as glues such as fruit tree gums such as gum arabic from acacia, cherry gum, etc. ... Dextrin is a glue of potato starch or rice starch. These are actually flour-based glues like all cereals that makes it possible to make all kinds of glues. For nearly 6,000 years, man has only disposed of this kind of natural adhesives. Cellulose-based adhesives, the main constituent of plants and in particular the wall of their cells, synthetic glues like Klucel types, Hydroxypropyl cellulose (HPC). Adhesives based on rubber and neoprene or polychloroprene, the first synthetic elastomer, epoxy structural adhesives that allow bonding with high mechanical strength (up to 15 megapascals in shear), these epoxy adhesives have been used since 1960 for bonding, with excellent durability, then the appearance of vinyl aqueous adhesives for wood, acrylics for plastics, more recently adhesives and polyurethane sealants. All this panel of adhesives allows the artist to adhere whatever he wants, without any limitation, if not his imagination.

Japanese Glue of Algae Funori

Funori glue is a natural vegetable glue with 100% dry algae. This glue is usually very stable, however, it can sometimes leave white spots caused by insoluble parts of algae. Before applying Funori adhesive to the paper, she must be prepared as follows :

Funori glue recipe

Put the dry glue in a container and then put on the fire, 1. Add water (approximately 5 to 10% of the volume ratio: 5 to 10 g of Funori glue in 90 cl of water). 2.Heat the glue in a water-bath vessel to moderate heat until the material is completely dissolved and then filter the solution through a cloth or stamen to remove the insoluble parts of algae. The viscosity of the adhesive will depend on its final application. This glue natural algae is essential for the preparation of the ink stick, but it is also used for Grounding paper and canvas. It is used by art restorers and for the consolidation of paintings.

JunFunori glue An exceptional glue

It is a water-soluble polysaccharide extracted from red algae of the genus Gloiopeltis urcata which grows along the Pacific coast of Japan, China and Korea. This alga has become notorious to restorers as a product particularly suitable for the consolidation of matt paints. The Funori glue is a product of natural origin and therefore of variable quality. To solve this problem, several Swiss restoration institutes have pooled their research in order to develop a particular purification treatment. The result is JunFunori (jun means pure), a standardized product that has been produced and tested by experts over a period of several years. With this glue, restorers now have an improved product to consolidate matt paints without altering the surface appearance of the paint, but why painters would not use it because of its high quality.

Basic Recipe for JunFunori Glue

Dissolve 1 g of JunFunori in 100 ml of cold water. Heat in a water bath to ± 55 °C for several hours until the glue has completely dissolved. Be sure to mix regularly during the dissolution process so that all undissolved particles are removed from the inner walls of the container. A fluid, smoother solution indicates a completely dissolved glue. The 1% by weight base solution is highly viscous and may be diluted according to its intended use. Make tests and experiment with your substrates, applying a second coat if necessary. Concentrations above 1.5% by weight may not completely dissolve.

dry JunFunori

Link to the JunFunori glue datasheet : http://www.-pigmente.com/media/pdf/63477e.pdf Japanese Glue of Algae Funori


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THE WAXES Waxes are products of vegetable, animal, fossil or synthetic origin. There are 24 different waxes because of their nature and structure. I will detail those that we can use in painting. The wax is a material that has a place somewhat apart in painting, it requires some preparation to be used as an adjuvant because it has no binding force itself. It must be mixed with a second component which will give it the ability to bond and adhere. Used sometimes hot, sometimes cold, the wax makes it possible to produce works with naturally flexible and thick layers imprinted with a certain vigor and suppleness, which do not let themselves be so easily apprehended.

ANIMAL WAXES Beeswax

Beeswax is produced by the secretion of the eight cherry glands located on the central face of the abdomen of the working bees: Apis Mellifera. The wax constitutes the alveoli of the hives. It is the most important wax for the painter, but also the most perennial. Its naturally yellow color, perhaps discolored by a treatment with boiling water and carbonate of soda, and then exposed to sunlight, so it can be used with the lighter shades, which constitutes a technique of wax painting. The beeswax has a complex composition of more than 300 molecules consisting of 14% free acids (cerotic acid C25H51COOH), 13% hydrocarbons, but mainly contains 71% esters (mono, hydroxy, di And triesters), or glycerides, palmitates, palmitoleates, hydroxypalmitates and oleates of higher alcohols. Its melting point is between 60 and 65 ° C. Its density is between 0.92 and 0.97 Kg / l. The beeswax is heat-soluble in benzene, diethyl ether and chloroform. All waxes have a great chemical inertia. Wax was used as a binding agent by Lascaux painters as a preservative by the embalmers of Upper Egypt and is still used for the manufacture of liturgical candles. Works made over 2000 years ago, such as the portraits of the Fayoum, were able to reach us in perfect condition. Waxes are kept indefinitely stored away from frost and humidity. The wax is used for the encaustic technique, to polish varnishes, to make the famous "Venetian Medium", for the manufacture of Cera Colla, a binder made of wax milk, in which is added an adhesive or a resin, In casein distemper recipes and also as a thickening, structuring and stabilizing agent for paints, both aqueous and oleoresinous. It is possible to make the wax miscible with water by the saponification process by mixing it with water and with a base such as ammonia. See recipes

bleached beeswax

Cells of beehive

Carnauba wax on left - beeswax on right


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THE WAXES 3 OTHER WAXES OF ANIMAL ORIGIN Wax sperm said spermaceti

whale "White Whale" or

It is drawn from a cavity of the skull of the sperm whale, called "the melon." It is a soft wax, melting between 45 and 50 ° C, it is white, fragile, and essentially composed of cetyl palmitate. It has the same chemical characteristics as paraffin. It was used in the 19th century in certain varnishes.

Wax of China

It is derived from the secretion of female coccids (Ceropastus Ceriferus), found on trees and shrubs, where they build cocoons of wax around the branches of trees such as the troene and ash that grow in China. It is a wax, of regional production, which is used only on site. Chinese artists use it for luxury decorations.

The carnauba wax consists essentially of aliphatic esters (40%), diesters of 4-hydroxycinnamic acid (21.0%), omega hydroxycarboxylic acids (13.0%) and fatty acids (12%). Its compounds are mainly derived from acids and alcohols in the range of C26-C30. The carnauba wax has a high content of diesters as well as methoxy-cinnamic acid. The wax is sold in several qualities, labeled T1, T3 and T4, depending on the level of purity. The purification is performed by filtration, centrifugation and bleaching. I use in proportion 40/60, the wax of carnauba mainly mixed with beeswax, for the making of the "Venetian Medium".

La Lanoline ou Suintine

Lanolin is a fat obtained by purification and refining of the wool. It comprises olein and stearin. Its composition is very complex. It is amphiphilic and forms very stable emulsions with water, it is a very hygroscopic species. It appears in a creamy white to yellow mass. It is imperative to purify the wax to use it in good conditions. It is mainly used for the care of leather, Flocons de lanoline pharmaceuticals and cosmetics.Melting temperature between 38 and 42 °C.Refractive index: 1.478-1.482.

Raw carnauba wax

VEGETABLE WAXES Carnauba Wax

It is a vegetable wax that comes from a palm tree originating from Brazil, which is also found in Haiti and Cuba, the Copernicia Cerifera, named in homage to the Polish astronomer Nicolas Copernicus. It is also called "tree for life". We harvest the secreted wax (To protect itself from the evaporation of its water) by its fan-shaped leaves, which can reach 2 meters of width. The wax is recovered on the upper surface of the sheets by cutting and drying them. Carnauba wax is hard and friable. Its melting point is between 85 and 101 °C, it is therefore harder than beeswax. It is one of the painter's natural waxes, the hardest of all. Carnauba wax


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THE WAXES 11 OTHER NATURAL WAXES OF VEGETABLE ORIGIN Candelilla wax

It is the purified wax taken from the leaves of the candelilla plant Euphorbia antisyphilitica. It is a substitute wax for Carnauba wax or beeswax. It consists predominantly of 42% C 29 -C 33 alkanes and 29% C 42 -C 64 esters. It melts at 68.5-70 ° C.

The wax of Japan also called Toxicodendron wax It is derived from the fruits of the Rhus Succedanea, a small tree of the Anacardiaceae family, native to Asia, found in China, but also in Japan and the Himalayas. Its fruits contain a fat (triglyceride).

Japan wax

The wax of Esparto

It comes from the valley of Albaida, a small region of Spain, which produces paraffin and a wax of regional and artisanal production.

Balanophora wax Candelilla wax

Ouricuri wax

It is collected under the leaves of a palm tree, ouricuri or nicuri (Syagrus coronata), which grows in Brazil. It melts at 79 to 84 ° C.

Jojoba wax

It is another Ceride, From the seeds of a dioecious plant: The Sysmondsia, which grows in the deserts of North America, India, Australia, Israel and Ecuador. This wax is substituted for sperm whale wax, the latter being protected.

It is extracted from the tuberous rhizomes (clandestine stems) of plants of the genus Balanophora and Langsdorf fia, which contain a flammable waxy matter. The stems are used as candles in South America.

Sugar cane waxes

They are widely used in the cosmetics and pharmaceutical industries. They are a potential substitute for expensive carnauba waxes. Sugar cane waxes, rich in fatty esters with very long chains, are extracted from a by-product of sugar, its foam which contains 3 to 4% of dry matter.

The plant waxes of Palme, of which there are nearly 3,000 species. Melting point between 50 and 65 ° C

plant waxe

Jojoba wax

Ocotillo wax is derived from a climbing cactus, plants from the South American and Mexican deserts.


89

THE WAXES Soy wax.

Soy wax, which is highly sensitive to temperature fluctuations, has a low melting point and can start to soften above 25 ° C.The candle makers discovered and developed this wax in the years 1991. It can be used in very small quantity as plasticizer for paints.

Its composition is very varied. It is used in encaustic, the manufacture of carbon paper, leather care products, grease making and ink manufacturing. Melting range between 82 and 95 ° C.

soy wax

The Raffia wax, taken from a kind of palm tree of Madagascar, the Raphia Farinifera.

FOSSIL WAXES

Cire de Montan

These are waxes resulting from the transformation, in the soil, of organic matter of vegetable or animal origin.

L’Ozokérite ou Ozocérite

Ozokerite or OzoceriteIn 1854, the first ozokerite mine opened at Boryslav, in Ukraine, at the same place where in 1861, one of the first oil wells will be set up in the world, by Robert Doms. It is a mineral wax, odoriferous, that we find everywhere and that we extract lignite. The deposits of Ozokerites occur in the form of veins. The slow evaporation and oxidation of petroleum result in the deposition of its paraffin dissolved in the cracks and gaps occupied by the liquid. The structure of ozokerite varies from a very soft wax to a black mass as hard as gypsum. Melting point between 61 and 78 ° C. natural ozokerite By Dave Dyet via Wikipedia

Petroleum waxes

They are waxy paraffins separated from crude oils when they are fractionated. Among these are microcrystalline waxes, which precipitate paraffin oils in the form of fine crystals. They are constituted by paraffinic hydrocarbons. Paraffine

SYNTHETIC WAXES Polyethylene Waxes

They are used in the packaging, Lubricants and inks.

white ozokerite

The Wax of Montan

It consists of purified montanic acids (C26-C32) And their esters with ethanediol and 1-3 butanediol and / or their calcium and potassium salts. It is similar to natural waxes.

Polyethylene Wax


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THE WAXES Synthetic esters And modified Montan waxes

Semi-synthetic waxes are created in the laboratory with natural raw materials such as Montan wax and amide waxes. They are produced by condensation of fatty acids and amines. Synthetic amides are used in cosmetology, for making candles and as lubricants.

The copolymer waxes

Based on ethylene-vinyl acetate (EVA) and ethylene acrylic acid (EAA), these waxes are well known in the formulation of paints, in particular as a primer for metals.

A Polyethylene The Wax A

It is a low density polyethylene wax. Its melting point is between 98 and 108 ° C. Molar mass: 6000 g / mol Molecular viscosity at 120 ° C: 950-1550 mm2 / s It is very sparingly soluble in all organic solvents at ambient temperature. It dissolves very well when hot in most solvents of low or moderate polarity, such as white spirit, turpentine, mineral spirits, toluene, xylene, Shellsol A and butyl acetate . It is used in the technique of encaustic To maintain leather, to protect metals and wood, and as an additive in hot melt adhesives.

synthetic amide wax

Microcrystalline Waxes

These are the first synthetic waxes to have been put on the market : Fischer-Tropsch waxes, which are used in packaging, adhesives, candles, cosmetology (sticks, etc.), wood encaustic , Etc. ... Melting point <75 ° C

Cire wax A

Fischer-Tropsch wax polyethylene wax


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PRESERVATIVES Preventol ON Extra

Preventol ON extra is a sodium 2-phenylphenolate salt with approx. 4 mol of crystallized water. Empirical Formula: C12H9NaO 4H2O Declared as food additive E232, not authorized in France, it is presented in the form of small square, whitish to yellow platelets. It has good biodegradability. It is used as an active ingredient for multi-purpose disinfectants and preservatives, hospitals, surgery, industry, and for paint as an antibacterial in aqueous solutions. It is a powerful preservative for the following materials: leather, adhesives and adhesives, lubricants, chillers, papermaking, fabrics. Also use as a preservative for whole citrus fruits. It protects against wood diseases. Used for the preservation of aqueous products such as glues, adhesive dispersions, textiles, additives for concrete, suspensions of fillers, ceramics, polishing agents, emulsions, etc. ... Antimicrobial material in the textile industry. As an active ingredient in disinfection systems. In the manufacture of pigments and their formulations. It is a remarkable preservative of aqueous solutions, glues and binders. Care should be taken : wear gloves and protective equipment when handling it in its pure state, as it is very harmful in this form. It become pink in aging, I personally found this faculty on preventol of more than 10 years. Density: 1.3 Kg / l Density in bulk [flakes] approx. 400 - 450 kg / m3 Solubility at 20 ° C: • In ethanol 2000 g / Liter • In isopropanol 1500 g / liter • In water 1200 g / liter [at 25 ° C.]. PH 2% in water between 11.1 to 11.8 Stable up to pH 14

Preventol RI80

Percentage of use

Bone glue, gelatin: 0.15 - 0.40% Solutions of albumin: 0.35. 0.50% Liquid starch glue: 0.15. 0.30% Dry starch paste: 0.20. 1.5% Dry Thickener: 2 - 3% Cellulose Adhesives and Thickeners: 0.05. 0.15% Paper industry, filling material suspension, coating color: 0.07. 0.10% Preparation with casein 0.10 to 0.25% There is also PREVENTOL RI80 a concentrated liquid preparation of benzalkonium chloride, allowing the formulation of disinfectants with a broad spectrum of action against fungi, bacteria and algae.

Preventol On extra


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PRESERVATIVES There are a small number of preservatives, plasticizers, stabilizers, pH correctors, dispersants and adjuvants,For the former, to extend the lifetime of adhesives, binders and materials, and for the latter to extend the capacities and characteristics of paints. It is necessary to ban the use of formalin (formaldehyde) which is very harmful for the paints (it ends up rendering the pulverulent films), moreover it is toxic. I will keep here the most useful in painting and if possible non-toxic.

The Camphor

The word "Camphor" comes from the medieval Latin camfora, from the Arabic "al kafur". The generic name of camphor applies to the various compounds which represent ketones, corresponding to secondary alcohols called camphols, they are somehow camphene terpenes. The camphors are found in the essences of various plants, especially those of the camphor, the Matricaria, the rosemary, the aspic, etc. ... There are two kinds of camphor, one natural and the other synthetic. What differentiates them is their direction of rotatory. Natural camphor is the crystallizable part of essence distilled from Japanese camphor wood, Cinnamomum Camphora, Camphora Officinarum Nees (Laurus Camphora L.) from the Lauraceae family growing in Japan and China. These trees resemble European linden or basswood. To obtain camphor, the trunk, branches and roots are reduced to shavings, boiled with water in iron pots covered with capitals, lined with rice straw in the interior, Camphor comes to condense. This constitutes the raw camphor. Camphor occurs in Cinnamomum camphora grayish grains, agglomerated, oily, and mixed with impurities. In order to extract the essence and the water, it is centrifuged and then subjected to the action of hydraulic presses where it is crystallized in benzene. The camphor thus purified is then sublimated in glass vases or iron pots. If a white and transparent camphor is desired, before the sublimation, a little lime, charcoal, or filings are added to the camphor. The refined camphor is presented in a colorless mass (crystallized in hexagonal prisms), transparent, unctuous to the touch, rather elastic, which can be scratched by the nail.

Its fracture is brilliant, its crystal texture, its warm and spicy flavor, its sharp and penetrating odor. Chemical Formula: C10H16O Its density is 0.992 Kg / l at 10 ° C. Its melting point is 175 ° C. Its boiling point is 204 ° C It volatilizes at ordinary temperature, it does not spray well after being moistened with alcohol, and better with ether. It is sparingly soluble in water (1 in 840), yet it acquires an odor and a camphorous flavor upon its contact. Water loaded with carbonic acid dissolves a much greater proportion of camphor, as well as water which is boiled for a long time in its presence. It is soluble in 0.65% alcohol at 95°, if water is added to this solution, camphor is precipitated as a flaky powder. A hot saturated alcoholic solution allows to deposit, by cooling, pretty crystals of camphor. Camphor is soluble in 1% alcohol at 90 °, 0.57% ethyl ether, 0.33% chloroform, 0.55% acetic acid, 4% olive oil and 1 , 5% turpentine. It is, moreover, very soluble in acetone, benzene, in fixed and volatile oils, fats and fused resins, etc. .... It is insoluble in glycerine. The synthetic camphor is made from the Pinene of the essence of turpentine (distilling below 170 °C), it has a rotatory power low or zero, the only one difference with the natural camphor. Camphor is a flammable substance. It is one of the best preservatives of aqueous solutions (with sodium benzoate and potassium sorbate), because it is not dissolved by them, and they also give them a pleasant odor. I have kept for 20 years experimentally, a glue of liquid skin, and so many other materials thanks to camphor.

Camphor crystals

Camphor


CONSERVATIVES AND MORDANT Crystalline Thymol

It is in the form of aggregates or in the form of a transparent white liquid, soluble in aromatic solvents. It is a preservative of watercolors in tube and a fungicidal agent of paper. Soak the media with a few drops. Chemical formula : C10H14O Thymol crystals

Sodium benzoate and Potassium sorbate It is a sodium salt of benzoic acid, sodium benzene carboxylate. E211 as a food additive. Benzoate Chemical Formula : C7H5NaO2 Sorbate Chemical Formula: C6H7KO2 I considered it food grade (some sodas contain), until very recently I read an article that talks about its toxicity. Benzoic acid and its salts, benzoates are listed possibly carcinogenic by the Association for Anti-Cancer Therapeutic Research (ARTAC, France). It is prepared by stirring 100 grams of benzoic acid in a little water, it is slightly heated, and liquid caustic soda is added. 10% aqueous solutions are neutral or slightly alkaline, check with a pH meter. Do not mix sodium benzoate with calcium salts and acid iron salts. It is a preservative of aqueous solutions which can be added to hide glues, gouaches, liquid enluminure, etc. ... I use Sodium benzoate and potassium sorbate it for hide glue and casein in conjunction with camphor which also perfumes binders. I recently used a liquid mixture of sodium benzoate and potassium sorbate, an antifungal, which I buy from Aroma-Zone, see suppliers. Sodium benzoate powder could be purchased from the pharmacist. Its density is 1,332.

The Clove essence

Cloves Are the dried flower buds evergreen of the tree a dozen meters high the syzygium aromaticum of the myrtaceae family. The tree is native to the North Moluccas, an archipelago to the east of Indonesia. The best quality comes from the Moluccas, Zanzibar (Pemba Island is the main crop area) and Madagascar. Clove oil is the essential oil of the clove,

which has a spicy smell with a burning taste. It is obtained by steam distillation. The main component is 70-85% eugenol C10H12O2, also called 4-allyl2-methoxyphenol, which is an aromatic compound. It has disinfectant properties like camphor. Exposed to air, it turns brown, and should therefore be used with caution. Use it drop by drop !. It is especially a preservative of emulsions and temperas, which is very useful when using fresh egg, but also in small dose a retarder for oil (Be carefull, because it can darken it, Try out). Use this essence in small doses, because its high dissolving power could alter the lower layers of the paints.

The Garlic

Garlic juice was often used by Byzantine artists. Scientific name Allium sativum L, garlic is a perennial vegetable plant of the family Alliaceae. It possesses bonding and sticky properties, since it contains an essential oil formed mainly of organic sulphide (Alliin bisulphide and trisulfide, a C3H5 radical of allyl alcohol and Allicin, some compounds of which exist in the essence of garlic Which has antibacterial, anti-fungal and antioxidant properties.When it is fresh, garlic exudes a transpanatural garlic rent liquid with a distinctly pungent odor, but becomes very dark by aging, this does not detract from its binding strength. COMPOSITION OF GARLIC OIL Compounds Percentage Diallyl disulfide 54,25 Diallyl trisulfide 1,34 Diallyl tetrasulfide 6 Diallyl sulfide 5,7 Methyl-allyl trisulfide 1,34 Allyl-propyl disulfide 0,13 Methyl-allyl disulfide 1,94 Chemical formula of allicin: C6H10OS2 Chemical formula of the allyl: C6H11NO3S

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MORDANTS AND PLASTICIZERS Garlic and garlic juice are used as a mordant in mixed techniques, oils / water and for laying gold, but it must be bonded with skin glue, casein or gum and it should be agglutinate, because alone, it is not a powerful adhesive unless it is very old. We prepare the garlic juice by pressing the pods, remove the green heart, put in a stoppered bottle for 2 months then crush them in a mortar or a mixer and pass them through a cheesecloth to separate the potential impurities. Garlic is used as a binding and adhesive agent for the preparation of plates for gilding. It is also possible to use the whole garlic, a pod is cut in two, which is passed over the parts of oleoresinous paints which it is desired to touch with temperate paints. The advantage of this technique is that it is possible to use pigments having a low refractive index (LapisLazuli, smalt, malachite, etc.). ...] on oil layers [previously sanded and degreased, it is only necessary to remove the glossy film on the surface], without hampering the legibility of the work. The garlic juice may be diluted slightly with water, but also with egg white. The "fat on lean" rule is defied with this technique, as with plextol K360, which perfectly hangs on the sanded and degreased oil, thus making lean retouching on matt oil let possible. I retouched with aged garlic juice, parts of oil painting on wood and these never moved. "The more the garlic juice is old, the better it is" as Cennino Cennini says, which I have personaly verified. [25]

liquid garlic prepared in 1999 to let it age, it becomes reddish brown after 10 years to become dark brown beyond 15 years.

Garlic liquid after sedimentation longer than 15 years, note the lighter sediment, a black liquid is staying afloat. Shake before using this aged garlic juice

The Alum

It is a double sulfate of aluminum and potassium hydrate of Chemical Formula for alunite KAl3[SO4]2[OH]6 and Al2 [SO4]3K2·SO4·24H2O for the alum. The natural alum or from rock corresponds to the mineral called Alunite. He was employed by the Egyptians and the peoples of Mesopotamia. It was extracted during the Roman period of mines from Tyrol, Sicily, Voltera and Aragonia. When they were exhausted in the Middle Ages, it was collected from

the coasts of Asia major, which constituted a serious obstacle to European industry at that time, as alum was in great demand for the dyeing of fabrics and for tanneries of leather. In addition to being used to etch textile fibers to be dyed, alum is widely used to prepare aluminate lacquers in the manufacture of pigments lacquered from vegetable and animal dyes. The alum from rock has an excellent thickening and plasticizing power, it makes it possible to extend the lifetime of the adhesives and to deprive them of their ability to swell in water (techAlum issolves nique often found in technical works); In water It is also used as a preservative for inks and other highly perishable substances. It is an alkaline product, it is necessary to check the final pH of the solutions. I use sodium benzoate as a preservative more readily.

Alum

Glycerin

Alumina sulphate at 200 g per liter of water

Glycerine or glycerol is a trihydric alcohol, a polyol. It is an organic chemical compound characterized by a number of - OH [hydroxyl groups] groups of Chemical Formula: C3H8O3. Each of these molecules is esterified by 3 molecules of fatty acids to form an ester molecule also called triglyceride, so it is a triatomic alcohol. Colloidal binders such as gums, glues and egg white used in water-based paints become fragile after drying, which can lead to cracks and tears in the paint layer. This disadvantage is avoided by adding glycerin to the binders (thus obtaining a plasticized film), so the paint film maintains a certain moisture after desiccation.


PLASTICIZERS AND MORDANTS In the past it was added in the form of a syrup consisting of a mixture of boiled water, in which honey or sugar was introduced, honey or liquid sugar was thus obtained. The disadvantage of these two substances is that they attract insects, so works containing glucose must be protected. Glycerin is a very good plasticizing material for aqueous paints, however, it must be added to the dropper. Glycerin also makes it possible to make watercolor pan or godet or any other paint tablet with water. Glycerol is low toxic, it is considered harmful. Density: 1.26 g / Glycerin cm³. Melting point between 17.8 and 20 ° C. After a certain time at 0 ° C., it solidifies. Boiling point: 290 ° C.

The Fig Milk

It comes from a group of mainly tropical plants of the family Urticaceae, but also found in Europe. There are more than 2,500 species, these are usually herbaceous plants, shrubs or lianas: Ficus Doliaria mort. The fig-milk is obtained, by making incisions on the young leaves and the stems of the fig-tree, a milky and whitish juice flows out, from which an acid ferment, called "cradin," analogous to that of the Carica Papaya (papain). Figs milk is used as a plasticizer in tempera recipes. Cennino Cennini speaks of it when he says to whip egg white with branches of fig trees in order to laminate it. In the north of Italy, there are many figs, so it is not surprising that painters have used it naturally. He played a considerable part in the perpetuation of the works of the past painted with the egg. The painters of the Middle Ages beat the egg and the tempera with fig-branches, the juice thus intimately mixed with the binder and plastifig milk cized it. Another of its properties is to delay the drying of tempera and other materials with which it is mixed. Its use goes back to antiquity, in the days of Pliny. There are references to its use in "De Arte Illuminandi" manuscript of enluminure recipes in Latin by anonymous author of the fourteenth century. Currently, 75% of French production is located in Solliés in the Var.

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Papaya of Carica Papaya

It comes from a persistent tropical fruit tree, native to southern Mexico, papaya or melon tree. The whole plant contains a white liquid, a protein of the latex family. The papain presents itself in tears, in rounded mass, in vermicular threads of unequal size. It is a hydrolysing diastase which is rapidly doubling proteins in neutral medium to give albumoses and amino acids (glycocolle, arginine, etc.). Its optimal pH value is 7. Papain is the dried and purified latex of the fruit of Carica papaya, it is a substance that contains a mixture of proteolytic enzymes found in the unripe papaya fruit. It is analogous to that of the ficus Doliaria. It is a natural plasticizer, ideal in temperas. Tests must be done beExtract of papain in powder form forehand, because the latex has a very marked tendency to yellowing. Add very little in paints. The latex also serves as a masking gum to make reserves.

Oxgall or the Fiel Beef

Bovine gall is the secretion of the liver collected in the cistifellea of the ox, an organ situated in the upper part of the abdomen below the lower surface of the liver. The gall is in the form of a green-brown liquid, becoming colorless and crystalline when purified. It has been used since the Middle Ages, there are many references to its use in ancient manuscripts of enluminure recipes. It is a wetting agent, moistening and dispersing rebel pigments, but it is also a degreaser for undercoats before painting in watercolor. It must be used sparingly to dilute paints in tubes or godets. 0.4% pure oxgall (or mixed with a little alcohol) improves the fluidity of the wash, thus allowing the pigments to spread better on greasy surfaces, thus avoiding the paintings to bead. It is used in the cracking varnish technique. It can be added to paints with hide glue, to make them brighter. Purified oxgall makes it posoxgall sible to use aqueous paints on surfaces such as acetate sheets, tracing sheets, etc. ....


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SURFACTANTS AND DISPERSING AGENTS Tween 20 also called Polysorbate 20

It is a nonionic surfactant which has emulsifying properties. It is classified as a food additive E432. Chemical Formula: C58H114O26. It is polyoxyethylene (20) sorbitan mono-oleate which has an HLB of 15.0. Density: 1.1 kg / l at 20 ° C. Viscosity, 25 ° C: Approx. 400 mPas. Flash Point: Above 149 °C. Point of fire: Above 149 °C. Soluble in water, alcohols such as methanol, ethanol, isopropanol, propylene glycol, ethylene glycol and cottonseed oil. Insoluble in mineral oil. Appearance at 25°C : Liquid Acid number KOH/g max. 2.0. Saponification number, mg KOH / g: 40 - 50. Hydroxyl number, mg KOH / g: 96-108 Water content: 2.5 to 3.0%. Polysorbate is considered harmful and carcinogenic, as all polysorbates although sometimes reported harmless. They are synthetic products made in 3 steps from sorbitol (E420). The water is removed from the sorbitol to form a sorbitan, which is esterified with a fatty acid such as lauric acid (E432), oleic acid, palmitic acid or stearic acid. At the end of the process, ethylene oxide is added with a catalyst to give polysorbate. Tween 20

Cyclomethicone D4 et D5

There are Cyclomethicone D4 and D5 which can be used as surfactants because they reduce the surface tension of the materials with which they are mixed. Appearance: colorless liquid Boiling point 172 ° C. Density: 0.95 Viscosity 2.4 mm2 / s Refractive index: 1.394 Tension superf. 17.8 mN / m Flash point (closed cup) 55 ° C Freezing Point 18 ° C Water content of 250 ppm Cyclomethicone

Ethomeen® C 12

Compounded with 100% Bis (2-Hydroxyethyl) coco alkyamine. It is a tertiary amine ethoxylate, based on a liquid coconut primary amine at 20 °C. Density at 20 °C 910 kg / m3 PH: 9-11 (1% solution) Melting point: 6 - 8 °C Boiling temperature> 200 °C Flash point: 100-199 °C Closed cup flash point (Pensky-Martens)> 100 ° C Pour Point (Pour point refers to the lowest temperature at which a substance continues to flow): 8 °C. Viscosity at 20 ° C.: 150 mPas. Foam height in mm, according to Ross-Miles: Immediately: 30mm at 50 ° C, 0.05% after 5 min: 25 mm Wetting power according to Draves at 25 ° C., 0.1% Distribution of Alkyl Chains Distribution of the C 8 alkyl chain = 5% Distribution of the C10 alkyl chain = 6% Distribution of the C 12 alkyl chain = 50% Distribution of the C14 alkyl chain = 19% Distribution of the C16 alkyl chain = 10% Distribution of the C18 alkyl chain = 10% Solubilities of 5% Ethomeen® C12 at 20 ° C: soluble in ethanol, isopropyl alcohol, propylene, white spirit, glycol, xylene and weak aromatic solvents. It is dispersible in water. Ethomeen® C 12 can be used as an emulsifier, wetting agent and dispersant. It is also used in hair coloring, where it helps to disperse the dyes by wetting the hair fibers. It must always be homogenized before use, unless the total quantity is used. It is easily biodegradable to more than 60% (28D, 301D of the OECD). Ethomeen® C 12 must be stored, handled and used in accordance with good hygienic practices. The information described above is based on the current state of knowledge and is intended to describe the product from the point of view of safety requirements. They should not be interpreted as guaranteeing specific properties. Ethomeen® is a harmful product, wear protective gloves and goggles. Harmful Substance = Bis (2-Hydroxyethyl) cocoalkylamine, CAS No. 61791-31-9 Ref. Kremer® and AkzoNobel® data sheetl


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PH COMPENSATOR Ethomeen® C 25

Chemical Formula: C30H63ClNO15X Polyoxyethylene (15) cocoamine Ethomeen is a tertiary amine ethoxylate, based on a coco primary amine consisting of: 1. Amines, coconut alkyl, ethoxylated from 98-100% 2. Amines, coconut alkyl 0.001-2% 3. Poly (oxy-1,2-ethanediyl), α-hydroxyω-hydroxy-0.001-2%

Ethomeen® C 25 can be used 4. 5. 6. 7. 8.

As an emulsifier in formulations Oil additives As surfactant As polar solvent thickeners As a pH compensator

It has a double action with polar synthetic materials: 1. as an emulsifier used for gel formulation such as Ethomeen C12 2. as a neutralizing agent for Carbopol, for example if its pH is too high. It must always be homogenized before use, unless the total quantity is used. [63]

Solubility

Ethomeen® C 25 est soluble dans le 2-propanol, l’éthanol, le propylène glycol, l’water et le xylène à une solution de 5%, mais il est insoluble dans les solvants aromatiques faibles et le white-spirit.

Precaution of use

Ethomeen C25 Avoid contact with eyes and skin. When handling, wear rubber gloves and goggles.

Dispersing Agent "Disperse Aid" Kremer®

Dispersant for polar and non-polar paint systems, for oil and water but it is also a wetting agent for aqueous and non-aqueous systems. It is a mixture of polyglycol esters, biodegradable, containing fatty acids (non-ionic surfactants). It is in the form of a liquid of yellow hue. Density 1.0 Kg / l at 20 °C. PH 6.5 to 2% in water. Surface tension 33 mN / m Easily emulsifiable in water but easily soluble in most aromatic and aliphatic solvents. Slight deviations have no influence on the application and its effectiveness. It improves the distribution of pigments in emulsion paints, for example if they are difficult to Disperse Aid disperse.

Moreover, this substance prevents possible flocculation of the particles which can be caused by the emulsifier. Particularly for the long-term storage of paints caused by mechanical or thermal shock, such as high shear forces. Disperse Aid is biodegradable, it is designed for use in low-VOC paints systems. The concentration is generally from 0.1 to 0.3% on the basis of the finished paint and can in principle be added at any stage of the production of the paints. However, it is common to incorporate Disperse Aid at the beginning of the paint formulation and then leave it on for a few hours.

Storage and Handling

Disperse Aid is sensitive to frost, it must be stored at a temperature between 15 and 25 °C. The product may be stored in closed containers at least 12 months after the date of use.Ref. Technical Data Kremer®

Triethanolamine

Crude Chemical Formula C6H15NO3 Chemical Formula of the compound : N(CH2CH2OH)3 Triethanolamine is also known as trolamine, the acronym TEA or the systematic name 2,2 ', 2-nitrilotriethanol. It is a colorless and viscous, an organic liquid chemical compound. It is a tertiary amine and a water-soluble trifunctional alcohol or trihydric alcohols. It is composed of 48.3% Carbon, 10.13% Hydrogen, 9.39% Sodium (N) and 32.17% Oxygen. Average mass : 149.188 Da. PH : 11 (20 g / l, 20 ° C). Density : 1.12 kg / l at 20 ° C. Melting temperature : 21 ° C. Boiling point : 360 ° C (1013 hPa). Flash point : 190 ° C. Vapor pressure : <0.01 hPa (20 ° C). Like other amines, triethanolamine acts as a light base due to the unique electron pair on its nitrogen atom. It is used as a pH compensator in preparations for a wide range of products. It is very convenient to counterbalance the pH of overly alkaline paints, inks and coatings. It has the same odor as ammonia. Triethanolamine is one of the basic chemical raw materials used as an emulsifier in water / oil and water / wax mixtures; For the treatment of rust in the treatment of metals; Also used in ink, it can play a role as a dispersing and water repellent agent. Triethanolamine


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ANTI-FOAMING ETC. ... Antifoaming

A foam is a substance that is formed by the trapping of gas pockets in a liquid or solid. Several conditions are necessary to produce foam : there must be a mechanical action. To create foam, agitation or action (W) is necessary to increase the surface area (ΔA): where γ is the surface tension. There are also micro-foams consisting of very small foam bubbles formed by dispersing a gas in a surfactant solution under very high shear conditions, thus very small gas bubbles are created, each surrounded by a film involving two molecular entities composed of stabilizing surfactant molecules. The surface of active components such as surfactants reduce surface tension and foaming. In general, an antifoaming agent is insoluble in the foaming medium and has surface-active properties. An essential feature of an antifoaming product is its ease of spreading quickly with foamy surfaces. It has an affinity to the air-liquid surface where it destabilizes the foam strips. This causes the breakage of the air bubbles and the distribution of the foam on the surface. The entrained air bubbles are agglomerated and the large bubbles rise more rapidly to the surface of the bulk liquid or they may burst and disintegrate

It is the only oil that is completely dispersed in water. The oil is expressed from the seed.sulfated castor oil is created by the addition of sulfuric acid to castor oil. It is considered the first synthetic detergent. 4. The fatty alcohols in C7-C22 are effective anti-foaming agents, but they are expensive. 5. Animal waxes and human cerumen, well known by the "enlumineurs".

Antifoaming from dimethylsiloxane is a silicone oil

which is used to prevent emulsions, acrylic and vinyl paints to foam too much, but also for other aqueous binders, especially during the preparation of paints or gels to the blender.[135]

R O

R Si

O

R

R

R Si

R Si

very flexible silicone chain in the shape of a chisel. Illustration ©2016 David Damour

There are some defoamers, as follows the most important in 2016 1.Anti-foaming agents based on polyethylene glycol E1521 and copolymers of polypropylene glycol or PEG are supplied in the form of oils, water solutions or water-based emulsions. They have good dispersing properties. Polypropylene glycol or polypropylene oxide is the polymer of propylene glycol. Chemically, it is a polyether of Formula HO - (CH2H2O) n-H. The PEG is used in many formulations for polyurethanes. It is also used as a rheology modifier, as a surfactant, as a wetting agent, and as a dispersant.It is available from [122]. 2.Silicone oils: Polydimethylsiloxane [O-Si (CH3) 2] n, also known as PDMS or dimethicone, is an organomineral polymer of the siloxane family. It is also a food additive (E900), used as antifoaming in cola beverages. Silicone-based defoamers are polymers available in the form of a water-based oil or emulsion. The silicone compound consists of a hydrophobic silica dispersed in a silicone oil. It is the antifoam that I use most often in my recipes, it has the advantage of lasting very long, so 40 drops are enough for 1 liter of binder. I also use it to make emulsions in conjunction with the Ethomeen C12 or C25. See Micro-emulsion p.380 and its precise dosage.[63] 3. Beaver oil or "Turkey Red Oil" is also known as sulfated castor oil.

silicone oil

PDMS Antifoam left 10 years out of light from 2006 to 2016

The defoamer is always effective and also of good quality even after 10 years off light. Its honey hue does not interfere and does not modify the shade of the film of the painting.

Wetting agent and emulsifier PM

It is an acrylic polymer for emulsification. Dispersing agent for aqueous media in order to reduce the surface tension of organic pigments 0.1 to 0.3%. Wetting agent PM is a modern emulsifier which offers many advantages for oil-in-water (O / W) emulsions and universal emulsification: it is a water-soluble polymer that easily attaches to The oil / water


WETTING AGENTS EMULSIFYING AND SURFACTANTS interface regardless of the type of oil used. Emulsions may remain stable for years even at temperatures above 40 °C. These emulsions are also stable to repeated freezethaw cycles. Low irritant. Low level of use due to its hydrogel nature and its high performance properties, it is possible to use only 0.1 - 0.3% PM dispersant. Thanks to this, it is possible to replace 3 to 7% of the traditional active emulsifiers which can be irritating. Rapid diffusion of the oil phase, the hydrophilic part of the hydrogel agent diffuses instantaneously upon contact according to the chaAgent mouillant PM racteristics of the surfaces. The oily phase is released and provides immediate impregnation of the substrate, eliminating the long latency observed with traditional O / W emulsions. Substances and base volume required to neutralize the dispersant to an approximate pH of 6.0 to 7.0

neutralize with a suitable base. 3. Use a quick mix (800-1200 rpm) to reduce the particle size and obtain a shiny product. Controlled homogenization may be useful, but variation in viscosity may result from high shear.A liquid nonionic surfactant with an HLB of 8 to 15 at a concentration of 0.10.4% such as Tween 20 may be added to the oil phase to reduce the size of the oil droplets and improve creamy appearance of the emulsion. Ref. technical sheet http://bit.ly/Agent-Mouillant-PM

Global surfactants Agents

The polyoxyethylene ethers of dodecyl alcohol, for example [C12H25-O- (OCH2CH2O) 6H, are added to achieve compatibility of the various materials in the paint systems. See Microemulsions p.380.

The emulsifiers

They are wetting agents to increase the colloidal stability of paints in the liquid state. See Microemulsions p.380.

Corrosion Inhibitor

It is a compound that prevents corrosion by forming a metal oxide layer. The surface becomes passive. The objective is to protect the substrate from rust. The corrosion inhibitors commonly used are : • Sodium molybdate • Zinc molybdate

• Sodium hydroxide NaOH (18% solution) ~ 0.5 • Potassium hydroxide KOH (18% sol) ~ 0.5 • Ammonium hydroxide NH4OH (28% sol) = 0.3 • Triethanolamine (TEA) C6H15NO3 ~ 2.0 • Tromethamine or Trolamine C4H11NO3 ~ 2.0 • Aminomethyl propanol (AMP®) C4H11NO1.5 • Ethylenediamine C2H4 (NH2) 2 ~ 2.0

Methods of implementation 1. Indirect method

1. Disperse the emulsifier in the oil phase until the pigment is wetted by the oil. 2. Add the oil phase (containing the wetting agent PM) to the aqueous phase, containing the neutralizing alkali, with vigorous stirring. Do not use tank homogenizers, but a single mixer (800-1500 rpm). 3. Wetting agent PM will swell rapidly in water causing high viscosity and formulation of a creamy emulsion.Continue stirring for 15 to 20 minutes.

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Zinc Molybdate

2. Direct method

1. Disperse the emulsifier by slowly sieving it in rapidly agitating water. A powder disperser may be used to accelerate dispersion.Foam may occur during this step. 2. Continue stirring, pour into the oily phase, and Sodium Molybdate


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PHYSICS OF PAINTINGS VARNISH

CRACKS IN THE VARNISH

CRACKS IN THE PAINT AND IN THE COATING

GLAZE FINAL COAT OF PAINT RE-ROUGHING

ROUGHING

CHARCOAL DRAWING ON COATING

FINE COATING AND PRINTING SKETCH AND PAINT LAYERS

COARSE COATING STRETCH-WRAPPED CANVAS IN THE COATING

SIZINGS AND COATINGS SUPPORT SUBSTRATE

Illustration

WOOD

2016 David Damour

THE REFRACTIVE INDEX

STRATIGRAPHIC STRUCTURE OF A PAINTING

A pigment has a hiding power which depends on its constant refractive index with respect to the binder in which it is dispersed and which also has its own refractive index in air. When light passes from one medium to another, light can change its angle of movement. The angle of refraction with respect to the angle of incidence in the air is called the refractive Index (represented by "n"). The Refractive Index is what makes a stick seem to bend when we introduce it into the water. Pigments with a high refractive index act as refractor of the incoming light until it is refracted at the point of impact of the first pigment grains encountered. The refractive index indicates the extent to which a light beam from the air of index n = 1.00 to penetrate into another substance is refracted. The greater the hiding power of a pigment, the greater the difference between its refractive index and that of the binder. For example, cinnabar of refractive index n = 3.0 ground with walnut oil of refractive Index n = 1.48, will be more covering than a smalt blue of refractive Index n = 1.48. To calculate the hiding power, the refractive index of the pigment is subtracted from that of the binder, ie for cinnabar: 3.0 - 1.48 = 1.52, which demonstrates that this pigment will be covered in all binders, whether aqueous or oleaginous. The smalt with index n = 1.48 will, on the contrary, be totally transparent in oil, since its IR is equal to that of walnut oil, whereas if it is ground with an aqueous binder such as water with an index n = 1.330 ie 1.48 - 1.330 = 0.15, it will be more covering than in the oil. It is therefore preferable to use it in an aqueous binder such as lean emulsions, egg white, pastel, cera colla, etc. ... The writing of the calculation of the index of refraction is thus written, ie n = n1 of x - n2 of y. On the basis of these observations, the hiding power of a pigment can

be reduced by mixing it with other pigments or fillers which have an index of refraction equal to or barely greater than that of the oil. It is very useful for making glazes : adding kaolin n = 1.55 makes the pigment more transparent (and not chalk a much less neutral matter).

REFRACTIVE INDEX AND LIGHT

The greater the difference between the refractive index of the pigment and that of the medium in which it is dispersed, the more intense is the diffusion of light. Refractive index = R.I

R.I =

Speed of light in vacuum Speed of light in the substance

DIMENSION OF PIGMENT PARTICLES

The particle size of the pigments has a paramount role in the refraction of light. In order for the light distribution to be as effective as possible, the diameter of the pigment should be slightly less than half the wavelength of the light to be dispersed. Since the human eye is more sensitive to green yellow light (wavelength about 0.55 μm), the theoretical primary particles of the pigments are 0.1 to 0.3 μm, microscopic studies Have confirmed this range for primary particle size. The optimal granulometry of the pigments to maximize their hiding and tinting strength in order to produce a layer of luminous paint should be between 40 and 63 μm, size verified from suppliers. Consequently, the painter must choose pigments of granulometry which are suitable according to the technique he wishes to make. The more a pigment is fine the more it is coloring, for enluminure and the gouache it is perfect, unfortunately too fine pigments are inadequate


PHYSICS OF PAINTINGS

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with certain techniques like the fresco for example and even for the oil, because if the pigment is too fine the paint will cracked, which is why it is better to choose larger pigments if they are to be crushed more thoroughly, idem case for minerals or you have to ask the supplier to grind them at acceptable particle sizes between 63 and 100 μm.

The solids volume of a paint is a fairly good measure of its quality. The volume of solids is expressed as : VP = Volume of pigment + Volume of solids of the binder divided by the total volume of the fresh paint x 100. The "100" is present in the equation because the volume of the solids is always expressed by percentage.

The tinting strength and the hiding power

PIGMENT VOLUME CONCENTRATION (PVC) Pigment Volume Concentration (PVC) is a practical tool for calculating the % of filler to be added in plaster and paint and also to choose in advance what type of paint we want, matt or glossy. It makes it possible to calculate the % of dry matter to be added to a given volume of binder. It is the ratio of volume of pulverulent or dry matter contained in the product to compare with the dry extract PVC is a number that represents the volume of pigment relative to the volume of all solids. PVC = Volume of Pigments ÷ by Volume of all Solids. It is written as the ratio of pigment to binder. Example : If a coating has a PVC of 40, so 40% of the total binderpigment mixture is due to the pigment, the remaining 60% are the solids and solids contained in the binder. The PVC gives us an idea of how much pigment is contained in the paint compared to the amount of binder. It is useful to know this because the binder has a very important role that is to bind the pigments and other raw materials in the paint. There must be enough binder to allow the paint to adhere properly on any surface. If, for example, as in a glaze, a paint has almost no pigment, it will generally be very bright and will have a PVC close to 5. Research has shown that the properties of a paint depend essentially on the ratio of pigment volume and fillers used and the volume of the dry film. Therefore, this very useful calculation is given by the concentration of pigment by volume called PVC. The pigment volume concentration is defined as the volume fraction of pigment (including fillers) in a single volume of a binder mixture for a given amount of pigment. A paint having a high PVC can be called a paint with a PVC of 50. A paint with a high PVC contains more pigment and less binder and will by definition have a matte finish, it will less anchor to the supports, so it will be less sticky and will therefore be more porous. On the contrary, a paint having a low PVC contains less pigment and more binder, it should be brighter, sticky and therefore less porous. Thus, PVC is referred to as "Critical PVC" or "CPVC" when the mixture of pigments and binder is such that it creates air voids in the paint film thereby increasing its porosity if the volume concentration of Pigment increases above the CPVC, the void space and porosity increases so that the tensile properties decrease.

The hiding power is the measurement of the ability of a pigment to opacify another paint film or a support, while the coloring power describes the ability of a pigment to change the color of another colored paint. The covering power of a paint is the measure of its ability to mask a colored contrasted background, its the results from the interaction between the incident light and the pigments present in the paint film. The particle size of the pigments also affects their covering and coloring powers, the greater the particle size of a pigment, the less it is covering and coloring, the finer it is ground, the more it is opacifying and coloring. It is also possible to reduce the covering power of a pigment by grinding it less finely, this assertion is only valid with the pigments which are prepared from minerals. By preparing some of them, the most common ones, we then have a starting range of fineness, which we can added to the commercial pigments finely dissociated (crushed) to a large extent between 10 μm and up to 200 μm for some fillers. The addition of silica of various granularities can also fill this office. Commercially available organic pigments range from about 1 to 10 μm whereas conventional inorganic pigments range from about 10 to about 80 μm while fillers are between 4 and 200 μm depending on the varieties.

THE VOLUME OF SOLID

The volume of solid is the measurement of the volume of solid film-forming ingredients in a paint pot, that is, the material that remains when the paint has hardened. In other words it is a measure of the actual volume of paint that can be used to determine the dry film thickness of the paint when applied at a predetermined spreading rate. The paint can be extended by addition of thickener and solvent. Thick paints do not always contain more solids in volume. Most industrial paints actually have a very low volume of solids and can often contain 50 to 60% water or solvent. For example, a common paint tin contains a dry matter content of 39%. This means that a 4 liter pot contains just over a liter and a half of solid material (actual paint). The other 2.5 liters are solvent. This solvent is sometimes necessary to paint-spraying, but beyond that, the solvent is useless.


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PHYSICS OF PAINTINGS

A film with a low CPVC with excess resin can give a shiny paint that reflects light because it has a smooth surface. A film with a large CPVC contains fewer binders, the pigment particles protrude through the surface of the film thereby increasing the surface roughness, the light that is diffusely reflected will not be perceived as glossy, paint will have a semi-gloss appearance. When the volume of pigment is sufficiently large, the diffusion also increases due to a larger air / pigment interface volume, and the paint film appears more flat / matt. As a result, the PVC of a paint film increases at a point that will be reached when the pigment and filler particles have actually absorbed all the binder (or the resins contained therein) available for wetting the paint area. The addition of further pigment will result in pigment to pigment contact rather than contact in the binder pigment film. This point is known as Critical Pigment Volume Concentration or CPVC, which corresponds to the limit beyond which significant changes in the properties of the paint film can be observed, for example, an increase in the permeability of a film to steam or a reduction in corrosion resistance. A very useful concept in paint formulation is to use the pigment volume concentration function as a percentage of the CPVC. It should not be forgotten that, beyond a certain percentage of PVC / CPVC, a significant reduction in the properties of the paint film occurs. Generally, the smaller the CPV of a paint, the better its external durability. This assumes that the paint is formulated with a durable good quality binder in the first place. PVC = VP divided by (VP + V1) where VP = volume of pigments and fillers and V1 = volume of binders (essences and solvents excluded) where Pigment volume divided by Pigment volume + Binder solid volume multiplied by CPVC can also be calculated using the following equation : 1

CPVC = 1+

OA x d 93,5

CPVC = 1 divided by 1 + AH multiplied by d, divided by 93.5 where OA= oil absorption in grams of oil to wet 100 grams of pigment and d = binder density (g / ml).Depending on their densities, the ability of the binders to wet or encapsulate the pigments may vary, which may affect CPVC.It is agreed that low density materials tend to wet the pigments better, however the type of binder also has a significant effect on the wetting properties of the pigment. Dispersants and surfactants are used to improve wetting and stability of the pigment dispersions in the binder.

CPV OF DIFFERENT TYPES OF PAINT

The figures below show the main trends fillers expressed in CPV. Mat = 50 to 80 Off-white = 35 to 55 Semi-gloss = 20 to 40 Gloss = 10 to 20 High Gloss = 7 to 15 Primers and Coatings = << CPV <50 (except for high zinc coatings CPV> 95) Intermediate layers = <CPV <35 Finishing layers = CPV <20 Glacis = CPV <5 with use of organic pigments. The addition of small amounts of silicas as fillers can greatly reduce the gloss. This can be seen with semigloss varnishes which may have a CPV of 5.

HOW DO PIGMENTS GENERATE A COVERING POWER ? The ability of a pigment to possess good hiding power is related to whether it has good absorption properties or good light scattering properties. Pigments such as spinel blacks and red iron oxides have excellent light absorption properties by absorbing most of the light that strikes their surface. Black is the most covering because it absorbs all the wavelengths of light, this absorption of light explains why dark colors heat up in the sun. For example, a black gloss paint can have a CPV of only 3% and yet have excellent covering power, so it can cover an area of 13 m2 with 1 liter of paint while a white paint with a CPV of 20% will have a relatively low covering power and will require two solid layers to cover 13 m2 with 1 liter of paint. It is a real shame that the most muddy colored paintings will have a very great hiding power. Vivid and muddy pigments tend to have excellent covering power. "Black spinel" pigments, for example, can give paints with 100% coverage with only a few percentage pigment by weight. Light can be considered as a beam of energy also called photons. The refractive index differences of white powders can be compared respectively with their power to kill the photons. Modern titanium dioxide is probably the most important white pigment used in the paint and plastics industry. It is by far superior to any other existing white pigment, in addition it is non-toxic. Just about anything you see in white in urban areas is titanium dioxide. Pigments such as titanium dioxide draw their opacifying power from their ability to diffuse light. The light scattering process is much less potent than the absorption and relies on a pigment having a high refractive index.


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PHYSICS OF PAINTINGS WHY DO SOME PIGMENTS HAVE BETTER HIDING POWER THAN OTHERS

Imagine the surface of a white paint enlarged microscopically thousands of times until we can see on each grain composing the painting a tennis player. Each beam of light energy called photons that comes to hit the surface is fired off by the "tennisman" with his racket. If you look around you will find on the paint that tennis players placed on pigments with high refractive index are powerful because they are able to remotely return all the incoming light beams. The players placed on fillers are in the second row and they miss most of the incoming light beams and as a result they pass through the paint allowing the support to be seen. On the contrary, the surface of a paint pigmented with spinel black could be described as a sea of petroleum. Any light beam projected on its surface will just enter, all its energy will be completely absorbed by it. There are other factors that influence the opacifying power of a pigment, such as the size of its particles and its crystalline structure, which is particular with pigments such as titanium dioxide. The crystal structure is the way a pigment is designed and constructed. As an example, the carbon may be present in one of these three forms - graphite, soot or in the form of diamond. It is obvious that the diamond will not absorb light very well. However, if crushed to a very fine particle size, it will be similar to titanium dioxide as to its hidng power and it will be white rather than black. Some suppliers like Kremer® sell diamonds in the form of fine powder.

Motorized sclerometer

Illustration

2016 David Damour

I use this device N°1 as an experiment to measure the thickness of paint film.

HARDNESS OF PAINT FILMS

The hardness of the materials and the films of paints are measured by specific apparatus, one of them is called a sclerometer. The notion of hardness has often led to misunderstandings on the part of industry. Since virtually all coatings and materials have viscoelastic behavior, the notion of hardness must be defined according to the resistance against mechanical action such as pressure, abrasion, or incision.

SHEAR TESTS, SCRATCHES AND CUTS

The motorized sclerometer is used to evaluate the hardness of the coatings according to the scratch resistance method. A test panel is attached to the support that moves slowly, while the chisel strikes the Il l surface. Depending on the test procedures, specific ustr at io or variable weights can be applied to obtain different n degrees of tear, from simple trace to destruction. A voltmeter indicates when the chisel is in contact with the metal support of the sample. Maximum size of the test panel: 100 mm x 150 mm. Thickness 1.6 mm (thickness 0.3 mm).

20

16

Da

vi

d

Da

m

ou

r

Manual scratch tester [57]


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PHYSICS OF PAINTINGS THE ADHESION TESTS [56]

Perpendicular incisions are made (see illustration below) on a dry paint film to be tested, then an adhesive tape is applied and it is removed quickly. As little as possible of small squares, must be removed by the tape for a film of good adhesion. More than 60% of the dry film must remain attached to the substrate for a quality paint film.[10] Hooking tests

Poor quality film

film of good quality

Excellent quality film Illustration

2016 David Damour

FILLERS IN OIL PAINTINGS

Paints are nothing more than systems of suspended particles in a liquid and depending on whether the suspended body is a pigment or a liquid (particles of oil in emulsions) we are in presence of a suspension. For a long time suppliers of crushed and paints in tube have used fillers so that the pigments do not uncouples from the binder in the tubes. Thus, in recent years, they have used modified organic clays called "Tixogel®", a high-efficiency coagulating agent, for oil colors for the best paints, for the worst Meudon white (chalk), which Makes the oil paintings more transparent and greyish. Prefer the silicates as filler for the oil, because they are more stable than the carbonates. [20] Some pigments, such as titanium white, which tends to flour, manganese blue or manganese violet, sometimes require a filler to better agglutinate under the muller or mill rolls. These extenders contribute to the dry hiding power (air-pigment interface) of low-cost paints and are used to control gloss, texture, suspension and viscosity. The main types of extender are carbonates (chalks), silicates (silicas), sulphates (gypses) and oxides (iron and manganese). Their particle sizes range are from 4 to 200 μm. Except in very special cases, a pigment needs no charge. In order to check if a pigment is pure, pour 50 grams of it into 200 ml of white spirit, stir and let rest (if you have a sedimentation cone, it is better), leave 24 hours at rest, if there is a filler, you should see it very visibly, like another layer in the mass. This method is valid for oil-ground pigments, then put into tubes, as well as for all aqueous paints, the only difference for these will be to dilute them in a large quantity of water, then leave to sediment.

Silice pure naturelle

Aluminum stearate

Fillers ratio in oil painting


PHYSICS OF PAINTINGS SOLIDITY TO CHEMICAL AGENTS AND TO LIGHT The "strength"term is used to describe pigment's sensitivity or durability to light, heat, solvents, acid or alkaline environments, etc. ... Each of these qualities is quantified using a "solidity scale" which evaluates a pigment from 1 (low) to 5 (excellent) in all cases except for lightfastness, which is subdivided by 1 to 8, 1 being a total absence of solidity, it is also said to be fleeting and 8 being an exceptional lightfastness [89]. The term "light resistance" expresses the ability of a pigment to withstand exposure, both direct and indirect, both natural and artificial, to light without undergoing visible changes in appearance. The more damaging components are found in the infrared and ultraviolet regions of the spectrum and as such a rapid assessment of the likely reaction of a pigment to long-term exposure to light can be assessed using equipment that maximizes artificial sources such as xenon or a carbon arc in a fadometer (a device for measuring the fading of a surface) can be used to assess the behavior of the pigment at accelerated exposure to compare them with "Blue wool, scale No. 1 to No. 8." The pigments can degrade and lose or change color by reacting with each other and with the components on the environment in which they are suspended or impurities in the air. The pigments can also lighten in the light, for example like the case of orpiment, it becomes more yellow.

PROPERTIES OF PIGMENTS TOWARDS LIGHT

White pigments have very little absorbing power with respect to their diffusion power whereas the black pigments have very little diffusion power with respect to their absorbency. Colored pigments selectively have both an absorbing power and a scattering power, that means they exhibit a dependent wavelength behavior, which explains how these two processes of "absorption" and "diffusion" give rise to what we can measure : the reflection spectrum or the spectral reflectance that gives wavelengths between 400 and 700 nanometers. Pigmented coatings can be characterized by their spectral reflection, but since the human eye can not see the reflection spectrum, it simply communicates color stimuli to the brain. The missing link in the chain is the conversion of the reflection spectrum by colorimetric color stimuli. The colorimetry refers to the quality of the hues perceived by the excitation of these same colors, which in turn is based on the reflectance spectrum. The principles of colorimetry are based on the fact that all color stimuli can be simulated by additive mixing of three selected color stimuli (trichromic principle). A color stimulus can also be produced by mixing impalpable so-called "spectral" colors.

105

Thus, there is a spectral distribution in the case of non-luminous hues, the perceived colors therefore emit spectral reflectance when a photon arrives on a pigmented film, so one of these three events may occur : 1. It can be absorbed by a pigment particle 2. It can be dispersed by a pigment particle 3. It can simply pass through the film (the binder normally being non-absorbent) The most notable physico-optical properties of the pigments are therefore their light absorption and light scattering properties. If the absorption is very low compared with the dispersion, the pigment will therefore be white. If the absorption is much higher than the diffusion over the entire visible region, the pigment will be black. With the colored pigments, the absorption is selective and the wavelength diffusion is in the visible region of the spectrum of 400 to 700 nm. Pigments and coatings can be characterized unambiguously by their spectral reflectance curves where spectral curve also denotes reflectance. The reflectance spectrum and therefore the properties of the pigments are also derived from their particle size.

PHENOMENA OF ABSORPTION AND DIFFUSIONS OF LIGHT

Opacity is regulated by the interactions of visible light with the paint film. There are two distinct approaches to achieving a complete opacity : 1.Absorption of light = Black pigment. 2.Diffusion of light = White pigment. Absorption of light = black pigment particles incorporated in a paint film suppress light entering in the film and transform it into heat. The aim is not to prevent light from reaching the underlying substrate, but rather to absorb light before it emerges from the paint film. The actual path length for absorption is twice the thickness of the film and for maximum opacity, the particle size should theoretically be about half the dominant wavelength. The diffusion by opacity can occur with another scheme : scattering that does not suppress light from the system redirects it out of the film, thus preserving the balance and intensity of the original colors. This redirection occurs before the light hits the medium and interacts with it. When this happens, the result is identical only with the absorption of the visual information of the support, but with a different appearance of the paint film. This gives a dark absorption film, while a luminous film results from diffusion. In practice, diffusion opacity is more difficult to achieve than absorption diffusion.


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PAINTING AND LIGHT

Illustrations FIG. 1

2016 David Damour

FIG. 2

FIG. 3

AIR BUBBLES PIGMENT

AIR

BINDER

BINDER BINDER

AGGLOMERATED

DISPERSED Schema pigment dispersions

FLOCCULATED PIGMENTS Illustration

2016 David Damour


PHYSICS OF PAINTINGS There are two reasons for this : firstly, the actual length of the absorption path is twice as long as that of diffusion (in order to achieve diffusion, the light must be redirected before contact with the substrate, while that absorption can still occur after light hits the substrate). Secondly, much less interactions between light and pigment are required for absorption opacity. Most of black pigment particles are very sensitive and reabsorb almost all of the light that strikes them, light is absorbed at its first contact with a dark pigment particle. Light scattering also occurs in contact with a pigment particle, but only one interaction is rarely sufficient to reverse the direction of the scattered light, and opacity of white is generally achieved only after light strikes several particles of light. Pigment (about a dozen). Hence, opaque black films can be much thinner and contain much less pigmented material than opaque white films which require more pigments to achieve perfect opacity.

THE POWER OF DIFFUSION

Le peintre devrait connaître ces mécanismes d’opacité et savoir qu’ils sont essentiellement indépendants l’un de l’autre. En résumé, les pigments foncés ne diffusent pas la lumière, mais l’absorbent et les pigments blancs ou très clairs reflètent la lumière, donc ne l’absorbent pas. L’artiste peut ainsi équilibrer l’absorption et la diffusion de façon à régler la luminosité de la peinture à sa convenance et ainsi jouer avec le bright-obscur.

THE CHOICE OF PIGMENTS

When deciding which pigment to use, there are several aspects to consider : 1) The intrinsic properties of the pigment = its color, its coloring power and its hiding power. (2) Physical and chemical properties : natural or synthetic, animal or mineral, organic or inorganic, chemical composition, water-soluble content, particle size, density and hardness. 3) Its stability = resistance to light, to heat and to chemicals : alkaline or acidic, etc. .... 4) Its behavior in the binders = interaction with the properties of the dispersion binder, its particular properties in certain binders, its compatibility with the other pigments and with the adjuvants. 5) The symbolic value is a very relative factor, it is judicious to know if you has to create particular and targeted images, for example, for a customer and towards which public the image is intended, as well as the choice of colors to the fashion will be preferred according to the pigments with strong emblematic connotations, as for advertising, for example, because the brands have their fetish colors that make them recognize at first glance.

THE OPTIMAL PREPARATION OF PIGMENTS

The optimum dispersion and stabilization of the pigment particles are important factors in determining the final properties of paints and by extension of the paint films. The pigments and fillers must be wetted and then finely ground and distributed as uniformly as possible. Under these conditions only, the hue, the intensity, the gloss, the covering power, the resistance to light can reach their maximum efficiency. The dispersion and stabilization of the pigment, which requires time and energy, is arduous without wetting agents and without suitable dispersion additives.

Dispersion of pigments in 3 consecutive steps [64] 1. The wetting of the pigment by the plate incorporation method 2. Dispersion of the pigment and the binder. 3. Stabilization of the pigment and the possible addition of a filler with the binder, stabilizers and various additives.

WETTING BY SPREADING OR BY PLATE INCORPORATION METHOD

Wetting the pigment particles is essential for an intimate distribution with a binder. The air trapped in the powder of the pigment must be completely removed and the pigment particles must be completely surrounded by the liquid medium, such as the binder. The processes involved in the wetting of a solid, that means by the pigment, are approximately described by the so-called "Young" equation : γs - γsl cos ∂ = Where : γl γs = Free surface energy of the solid γsl = Solid/liquid interface energy γl = Surface tension of the liquid ∂ = Solid/liquid contact angle With wetting and diffusion, the contact angle is zero, so the cosine term is 1, this occurs when the free energy surface of the solid less energy solid / liquid interface equal tension of the liquid surface, and which is written as : γs - γsl = γl. In order for the (liquid) binder to wet the pigment (solid), the surface tension of the binder must be less than that of the pigment. A liquid with a low surface tension moistens the pigments better than if it has a high surface tension. The additive will contribute to the wetting by reducing the surface tension of the liquid, however the wetting and the dispersion of the additives is not only limited to the surface tension of the liquid. Since the [ pigments/fillers ] groups adsorb the binder, they also modify the boundary surface of the binders. The surface tension therefore lies not only between the pigment and the binder, but also between the additives and the binder.

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PHYSICS OF PAINTINGS

The additives which allow wetting and dispersion reduce at the same time the surface tension of the liquid and the interface tension between the pigment and the binder, in this way the wetting is doubly promoted,that is why they are used.

THE DISPERSION OF PIGMENTS

The pigment particles are now impregnated with the binder, which is itself enveloped by the surface of the additive. The surfactant reduces the reactions with the pigment and thus lowers the viscosity of the starting paint paste. Thanks to this, more pigment can be added in order to make paints that are richer in coloring matter, which is an advantage that is not negligible for mechanical dispersion processes such as roll mills. With this dispersion process, the pigment agglomerates are divided into particles and small pigment aggregates. Usually aggregates can not be broken because these particles are so intimately linked that it is almost impossible to dissociate them. Pigment manufacturers take this phenomenon into account in the production of powders by controlling the proportion of aggregates, as their number may affect the hue or final shade of the pigment powder. Each process of dispersion to break up aggregates and agglomerates requires energy. This essential task is given for information by the following equation : dW = γ·dA où W= Energy of surface Interface γ = Surface tension A = Interface area

Illustration

2016 David Damour

This equation indicates that for an increase in the surface area dA during the dispersion (by breakage of the agglomerates), an energy contribution dW is necessary, which is proportional to the surface tension γ. The smaller the surface tension, the greater the increase Of the surface area is large and an amount of energy applied. Thus, due to the presence of a dispersion additive, as the surface tension is reduced, less energy is required.

THE STABILIZATION OF PAINTS

In the dispersion process, the aggregates (FIG 1 on the previous page) are divided into particles and small conglomerates. The formation of particles results in an increase of the boundary surface with the liquid medium of the binder (FIG 2 on the previous page). The higher the interface voltage, the more difficult the reduction of the interface area. The particles, therefore, agglomerated, form so-called "flocculates" (FIG 3 on the previous page). The term floccules indicates an agglomerate occurring in suspension. By dispersing the additives, we suppress the formation of flocculates. To stabilize the distribution of fine particles, the molecules of the additive must be strongly adsorbed on the surface of the pigment. This means that the additive molecules require groups or segments that can interact strongly with the surface of the pigment by ionic bonding, dipolar interactions or hydrogen bonding. Depending on whether the formulation is water or solvent based, whether the pigment is a metal or not, different mechanisms can occur.


109

PHYSICS OF PAINTINGS A rather remarkable example is the case of carbon blacks. Their surface areas are far superior to other pigments. Therefore, a larger amount of dispersant additive is required to effectively cover a surface, because the carbon black does not have a conventional molecular structure.

THE SHAPE OF THE PIGMENT PARTICLES

The shape of the pigments can not be evaluated precisely with the naked eye, it necessarily requires a microscope, however in the specialized literature their forms are well documented. The pigments have several dimensions, the particle size and a well defined particle shape. The intrinsic shape of the pigment particles is determined from the crystalline form of the raw materials that make up the pigment, but it also derives from the pigment manufacturing method. As a rule, moistened pigments tend to have edges that are more polished and rounded than those produced by dry grinding. The very divided pigments (very fine) of the order of 10 microns also have smooth outlines. The primary particles of the pigments can be round, square, irregular in the form of knots, stick-shaped, needle-shaped or bladeshaped plates. The structure of the pigment particles also affects the property of paints such as firmness, effusion, brushability, sedimentation and the advantages or disadvantages they impart to the films. The needle-like pigments are several times longer than their smallest circumference. The rod or stick forms give more resistant paint films than can be compared to reinforced concrete with its Tor rods immersed in its mass. Thorn-like particles tend to settle in the paint film and create a lattice structure, and are more easily dispersed than a compact layer formed by nodular, round or square particles. These sharp pigments are Illustration

long and they can create asperities and across the film of paint and thus give matt satin coatings that lower their shine. This rough and abrasive surface can serve the base of the lower layers and intermediate layers creating a whole network of irregularities which allows a better cohesion and adhesion of the following films. The blade-like pigments create thin slices that will consolidate the film. They create bridges inside the paint film, thus making them airtight to the passage of liquids and vapors. The knot-shaped, round and square particles absorb less oil than the other types of pigment form, allowing the preparation of rather dull paint, easy to apply while the needle-shaped particles, in the form of a blade and In the form of bars tend to increase the consistency of the paints because of their affinity for the oil. The shape of the pigments of course must be taken into consideration, but this is not the only value since the size of the primary particles of the pigments and their tendency to agglutinate should also be appreciated. For example, the case of the black smoke or vegetable black proves that their shape is not sufficient to define them, although the latter is round, they nevertheless consume an enormous amount of oil because their particles are very small , Thus very often during the grinding of such pigments their shape changes from a round shape to a lattice shape.

EXTENDERS AND STABILIZERS

To prevent inversion of the dispersion process, we surround the pigment particles by extenders blocking agglomeration of particles. The stabilization is achieved by the addition of these substances to establish identical loads on all particles. The surfactants then form agglomerates of a few tens or hundreds of molecules with the pigment and the binder, creating an attraction (unnatural at the base).

2021 David Damour

NEEDLES - THORNS - ACICULAR CYLINDERS - RODS The length is greater than the other two sides

PLATELETS - SQUARES - KNOTS Different dimension of the sides which have more or less the same aspect

SLATS The thickness is smaller than the other sides

ROUND - SPHERICAL equivalent dimensions


110

PHYSICS OF PAINTINGS - GRINDING The surfactant additives are components of the polyether silicone copolymer family. Ethomeen C 25 and Disperse Aid, for polar and non-polar artistic paintings, as well as phosphatidylcholine. There are natural surfactants that can be used, such as oxgall and to some extent glycerin for aqueous paints. For water, sodium polyphosphate can be used to stabilize the aqueous mixtures. We can also mention ammonium lauryl sulfate (ALS). There are also mild multifunctional surfactants such as acylglutamates composed of a C8 or higher chain fatty acid and L-glutamic acid as well as sodium cocoyl glutamate, derived from coconut oil and fermented sugar. There are other very light non-ionic surfactants, such as coco glucoside, lauryl glucoside or decyl glucoside obtained from sugar and vegetable oil, these are alkylpolyglycosides (APG), sugar esters that are advantageous as surfactants, low-cost and non-toxic. Sodium coco sulfate, also anionic, is a sulfate derivative (ester) of fatty acids of coconut oil. Modern high performance polymer filler additives and dispersion additives of all types of pigments find multiple uses with all types of adhesion groups, such as the TEGO® Dispers 755W most commonly used in the manufacture of Industrial paints sectors.

THE OIL ABSORPTION

The pigments of small particle size have a large specific surface area per unit mass; Therefore, more oil is absorbed at the surface. Likewise, the needle-shaped, blade and irregular particle pigments have a high oil absorption rate compared to the round, square and knotted particles due to a larger area. Pigments with a spongy structure such as carbon blacks also have a high oil absorption rate due to the penetration of oil into the interstices. The oil absorption rate is a value on the amount, and therefore the density of the pigment is an important data. Dense pigments often have lower oil absorption rates than pigments with a low density, provided that their size and particle shape are of the same order. Apart from particular characteristics of the pigments mentioned above, other factors such as the energy input during grinding, including the duration and shear force, the acid value of the oil which is the mass of hydroxide of Potassium (KOH) expressed in milligrams should be about 3 plus or minus 1 mg KOH / g and the presence of water within the pigment matrix determines its oil absorption rate.

THE FINAL GRINDING OF THE PIGMENTS

After all that has been said, It is clearly obvious that a quality paint system is only possible from the moment when dispersant additives such as: ethomeen, disperse aid, disponil, etc. ... are involved. They will allow a greater affinity between the pigment and the binder.

The wetting remains important because it will prepare the pigment and thus allow to to involve less physical force to obtain a paint of good quality possessing optimal properties of surface. I advise to always wet the pigments before grinding especially the organic pigments, which is why I often grind them with water even if I have to do an oil painting, water is not a problem In the production of oleaginous paint, the oil will expel the water to leave a paste of oil. In industry, this process is called "Flushing" or more commonly in French a "rinsing" process which is widely used in the preparation of concentrated organic pigment dispersion for color printing inks. The process can be described as a direct transfer of pigment from an aqueous phase to obtain a non-polar oil phase. The pigment is mixed with an oil-based vehicle or binder and then the water is separated automatically and spontaneously from the surface of the pigment and replaced by the oil binder. Painters of the past, to name but one, "Rubens", crushed its lead white first with water to expel the acetate of lead, in order to realize a white of better quality and of Increased purity. The grinding with water can be performed in an agate or porcelain mortar according to the size of the particles of the pigments, which must ultimately have an average dimension of between 10 and 30 μm maximum, for use in most paint systems. The dimension of commercial pigments is often indicated by conscientious suppliers, because the granulometry is very important as we can see in the realization of the dispersions, do not hesitate to ask him to grind to the dimension of your choice (he possesses all the tools for this purpose), you will thus achieve paints with increased coloring power.

CONCLUSION

Physical paintings is a difficult area and practice its precepts is not always easy, but one step at a time we finally understand its mechanisms and assimilate. It is sufficient to know that the pigments have a major influence on the physico-chemical properties of the paint films, just as much as the binders, so choose them accordingly.


111

PHYSICS OF PAINTINGS - FLOCULATION

THE FLOCCULATION OR WHY IT IS ALWAYS NECESSARY TO GRIND AND STABILIZE THE PAINTS THAT ARE PUT IN TUBE AND IN POTS

Suspension of Stable Pigment Agglomerates

Flocculation is the formation of bulk clusters of pigment particles (flocculates) in a suspended fluid system. It occurs when there is not enough repulsion between the droplets to keep them at a distance from one another. Flocculation may be '' high '' or '' low '' according to the intensity of the attractive energy involved. Flocculation is often the result of an insufficiently ground initial dispersion, dispersant type or inadequate concentration.

Separation of particles

Typically, these flocculates are easily broken under moderate shear but will rapidly re-form if the particles are left free to move through the mass of the binder.

FLOCCULATION CAN CAUSE SEVERAL MAJOR PROBLEMS 1. the loss of opacity and coloring powerThe floccules do not disperse as efficiently as the primary pigment particles.

2. Excessive viscosity and poor fluidity Agitation will often stabilize the suspension, but flocculation will occur at rest.

TEST OF THE DEGREE OF FLOCCULATION To determine whether the pigment is fully dispersed or remained dispersed over time, a color tone is prepared with a titanium white. Half of a sample is taken and the excess paint is recovered and set aside until it is dry. Then take a small amount of the original fresh mixture and place it on top of the dry paint film. This paint is then applied by pressure in a circular movement in order to disperse the paint. If the pigment is completely dispersed, the rubbed paint will show a stronger hue than the original sample. Surfactants and agglutinators are indispensable in painting, especially if placed in tubes. Without emulsifiers, the aqueous and fatty phases of the emulsions would separate and form undesirable floccules. (See microemulsions)

Stabilization of the dispersion Flocculation

Illustration

2016 David Damour


112

THE HYDROGEN POTENTIAL CALLED pH The hydrogen potential or pH is a measure of the chemical activity of hydrogen ions H + in solution, especially in aqueous solution. These ions are present in the form of oxonium ion (also, and improperly called hydronium ion). PH measures the acidity or alkalinity of a solution. Thus, in an aqueous medium at 25 ° C., a pH solution below 7 is said to be acidic. The lower its pH, the more acid it becomes. A pH solution above 7 is said to be basic or alkaline because its pH is shifted away from 7 (Increases) and the more basic it is. A pH solution of value 7 is said to be neutral. So there are 14 graduations since the highest acidity between 0 and 6.99 to the highest alkalinity, between 7.1 and 14. It is necessary to take into consideration the temperature (and the quantity of alkali or acid) that can raise or lower the pH of a solution.

LIST OF PHS OF SOME SUBSTANCES BASIC SUBSTANCES Soda

14

Potash

13

Ammonia

12

Casein binding base

10 à 12

Water of magnesia

10,5

Soap

9,0 à 10,0

Borax

9,5

Sea water

7,9 à 8,3

Mountain water

8

Pure water*

7,0

Blood

7,34 à 7,45

Sodium chloride sol.

7

Human Saliva

6,5 à 7,4

ACIDS SUBSTANCES

pH color circle By "TheChimist" via Wikimedia

pH buffer solutions 4.01, 6,86 et ph 7

butter Cow milk

6,1 6,5

Acid rain

< 5,6

Tea

5,5

Urine

5à7

Coffee

5,0

Cheese

4,5 à 6,5

Beer

4 à 4,5

Apple juice

3,5

jam

3,5 à 4

Orange juice

3-4

Wine

3,5 à 4

Rhubarb

3,1 à 3,4

Grape juice

3 à 3,5

Vinegar

2,9

Cola

2,5

Lemon juice

2

Gastric acid

1,8

Acid battery

< 1,0

Hydrochloric acid

0


113

THE pH METER The pH meter is a portable electronic device that allows the display of the numerical value of the pH.

It is constituted at the end of a probe and a glass electrode for measuring and a reference electrode. Its operation is based on the ratio between the concentration of H 3 O + ions (pH definition) and the electrochemical potential difference that is established in the pH meter when immersed in the solution studied. It makes it possible to determine the value of acidity and alkalinity of any solution.

Ammonia is a product in solid form of white color in fine granulate which is very irritating and has a strong pungent odor of ammonia, a gas which mainly composes it and escapes spontaneously. Ammonia is a chemical product of Formula NH4OH, it is an alkali, a base which makes it possible to saponify the materials of the painter in order to make them miscible with the water and to allow their intimate mixture with the oleaginous substances, like wax with oil for example to make the Venetian medium .The mean pH of ammonia in solution is> 11.5.Warning Ammonia is toxic and dangereuxx, wear mask and gloves during handling.

http://bit.ly/Fiche-Securite-Amooniaque

Pure ammonia

Manual Calibration pH Meter

Probe and glass electrode of the pH meter which allows the measurement of the acidity or the alkalinity and the temperature for this model

PH meter with automatic calibration.

You should rather use the right-hand model because the manual pH meter go out of correct adjustment very quickly and is too complicated to calibrate with his screw on the back of the device and the screwdriver provided for this purpose, whereas this automatic model AD11 from Adwa® simply requires pressing the set button, immersing it in a pH4 buffer solution and then immersing it in ph 7 buffer solution and calibrating is done, moreover it does not disrupt itself as quickly as its manual namesake.


114

THE MINERALS The Minerals

Minerals (unified structure) are found in rocks (accumulation of minerals), which are themselves aggregates of one or more types. Rocks and minerals were formed all along the geological history of the Earth. Some minerals are used to produce colored powders called "Pigments". The word pigment which comes from the Latin "Pigmentum" means coloring matter. A pigment is a natural, organic or synthetic (chemical) substance which is mixed with a binder to form a solid paint film that attaches to the surface of the supports. Thus many pigments are obtained by the fine grinding and purification of natural mineral and inorganic materials rock. All the minerals are not usable in painting, and in particular with oil painting, I am thinking about copper, which is often found, beware of its instability. The point is not to amass any pebble and grind it into a pigment, it would be too simple.

How minerals are formed

The main minerals of interest to the painter are those which provide colored materials, they are called "hydrothermal minerals" because they precipitate from aqueous solutions at high temperatures between 50 and 600 ° C, often in connection with an igneous activity (volcano And heat). Most of the time, they are deposited in veins in fractures or in cracks of enclosing rocks. Thus, the rocks, veins and walls enriched with minerals are subjected to the action of atmospheric agents. Sulphides which can be oxidized form soluble sulphates. Others can be dissolved and some react with deeper sulphides and enrich them by removing

Orpiment

Malachite

certain elements, for example by replacing the iron with copper. Sulphides such as Cinnabar, Covelline, Galena, Molybdenite, Orpiment, Pyrite, Réalgar ... can be transformed into carbonates, silicates, oxides by reaction on the walls of the rocks. A new group of minerals can then be formed, and the surface exposed to atmospheric agents (outcrop) which can be leached, can be changed into a new oxide or several, depending on the conditions. "The crystallization which is the passage from a disordered liquid, gaseous or solid state to a solid ordered state, is controlled by very complex laws" (Atlas of Mineralogy). Crystals are formed by various factors such as temperature, pressure, evaporation time. Most minerals that crystallize under these conditions are minerals that contain metals. Hydrothermal deposits close to the earth's surface can be altered by low-temperature (meteorite) water effusions. Thus primary minerals are transformed into secondary minerals. Metals: silver, copper, iron, mercury, gold, lead. Semi-metals: antimony, arsenic, bismuth. Non-metals: diamond, graphite, sulfur. Here are some primary minerals: gold, silver, copper, pyrite, galena, marcasite, sphalerite, magnetite, hematite, ilmenite, cassiterite, fluorite, quartz, calcite ... which may give some secondary minerals such as cerusite, malachite, azurite, etc. ...

Where do we find the Minerals?

You can obtain from a mineralogist (see suppliers 8) who will find for you the most beautiful specimens especially so that you can make pigments.Or you must

Céladonite

Fuschite

Crocoïte

Amazonite

Azurite

Ocher Saint Georges sur la Prée Lapis lazuli

Purpurite

Rock crystal

Thulite Chrysocolle Turquoise

Alba Albula Vivianite

Talc Réalgar

Lapis lazuli

Ocre rouge du Mexique

Limonite Goethite

Cinabre Hématite

©2021 David Damour Collection of minerals

Rhodocrosite


115

THE MINERALS go on "Campaign". As a general rule, the minerals that interest us, flush and are located in all mountain areas. The rock is exposed in the often renewed areas, the frequent landslides, the base of the mountain walls, the bed of torrents (the streams in general) and the bottom of the valleys.The old mines and quarries are also places conducive to the discovery of minerals and especially in the upper parts of the mineral deposits called oxidation hat. And Internet of course.

How do we choose minerals?

It is easy to know what minerals are most likely to give saturated and vibrant hues. Know that all the minerals do not give beautiful pigments, particularly if they are needle-like or accicular (thin spines) and vitreous (clear and colorless), ie the percentage in the host rock is not sufficient enough to give a reasonable quantity of pigments once the mineral is crushed, that's why in commerce some of them are very expensive because they are very rare. Make sure to choose compact masses (such as malachite No. 1) containing the fewest veins of color opposite to the desired pigment. We need a mineral that is not in an advanced stage of oxidation, such as azurite No. 4. That's why the choice of minerals is paramount.

1 ©2016 David Damour Malachite of high quality

2 ©2016 David Damour Azurite of excellent quality

Recognizing quality minerals

I will try to explain to you the difference between an ideal mineral to provide a saturated pigment of good quality after purification and a mineral that will best give a gray powder or too white but not a bright pigment. 1.While this is very rare, the mineral must contain the least marbling possible. 2. The overall color of the mineral must be of the desired range, if we want a green, the mineral must be the same, here for malachite and azurite, we find that mineral No. 1 is entirely green with little Dark green at its base and for azurite No. 2 it has a grayish part, but as it can be separated by crushing before powdering, this is not inconvenient. Whereas specimens 3 and 4 are inadequate. 1. Malachite No. 3 is too mottled and too dark, a large part is acicular and vitreous, moreover it contains little clear malachite, as it undergoes very thorough oxidation. 2. The azurite No. 4 is far too advanced in oxidation and in vitreous form, it will hardly supply a pure pigment. It would have been necessary to find this azurite, millions of years ago, before the chemical transformation of its copper changed into another compound, such as silica, for example, and irreparably corrupted its original blue tint. However this azurite of Oujda like the malachite N ° 3 is magnificent for a collector, but not for the painter who wants to realize pigments and pure color paints.

3

Malachite advanced oxidation stage

4 Azurite of oujda By Didier Descouens via Wikimedia


116

FROM MINERALS TO PIGMENTS

Where do the pigments come from?

Obtaining pigments from minerals requires considerable but very rewarding work. Inorganic pigments come from rocks, ochres or earth, minerals or inorganic chemistry, they can be reproduced with chemical and mechanical means. It is possible to make some of them with chemical substances, metals and a muffle furnace, however, it is an arduous task that requires great skills and much accuracy in the dosages and temperatures to be developed. Thus it is simpler to obtain them from nature, from minerals. The pigments are in the form of fine powders, the particle sizes of which are very variable, in range from 0.1 micrometer (0.1 μm) to a few hundred micrometers (eg 200 μm). Pigments - unlike the dyes - are insoluble in the liquids in which they are dispersed, except very rare exception such as the case of umber's

Chromatic circle made by half with egg white, then scanned and completed by half with RGB colors flat tints on computer.

earth.

What is a paint ?

How should pigments be named?

We should not say "a red pigment," a term too general, but "red cinnabar", an active ingredient, mercury sulfide which composes it and gives it its color, otherwise you need to use the Colour Index.

A paint is a varied and polyphase chemical system, heterogeneous and arranged once the film is dry as a discontinuous solid phase called film or coating. It is the result of mixing one or more pigments with a binder, a liquid, a mixture of water, oil, or both, with a gum, a resin or any other component, It is, which gives creamy and sticky materials that will allow the paint to adhere to any supports or substrates. Pigments are particles added to the system to modify its properties. The first modified properties by pigments are appearance, including color, but pigments are also used to modify the physical characteristics of the system in conjunction with fillers or various inert adjuvants such as silica or barite white.

Cinnabar and cast iron mortar

"Coloribus versus Pigmentum"

Color is a sensation that the brain generates and which we designate with words (light strikes cones and rods: photoreceptors located at the bottom of the eye) while pigments are physical and chemical materials, palpable, affiliated In a "Color Index", a generic and universal way of identifying, distinguishing and naming all existing coloring matters, including pigments, in order to identify them.To know more : http://bit.ly/2bhIemS

Illustration

2021 David Damour


MATERIALS FOR MINERALS PREPARATION One of the natural processes for obtaining colored pigment powders begins with the crushing and purification of minerals, rocks or various compact materials.

117

The 4 steps to get a powdered pigment.

* 1. It is necessary to crush the minerals that are deposited in a strong canvas, then with a hammer they are reduced in small pieces until obtaining small grains of about 1.5 mm of side * 2. The smaller the granular materials are, the easier and simplified the grinding with the iron mortar will be. Start preferably the crushing of the materials in an iron mortar. * 3. The granules are crushed with a pestle until a sufficiently fine grind is obtained, of the order of approximately 80 to 200 μm, in order to be able to begin the purification steps with an Agate mortar. * 4. The smaller, finer, or dissociated the size of the particles, the more luminous the pigment will be.

Illustration and photos © 2016 David Damour

Mortars and pestles to convert minerals into pigments and powdered materials


118

OCHER CRUSHING USE OF A CAST IRON MORTAR

1 Cast iron mortar for crushing hard materials and an electric mill (see Suppliers No. 28) to grind the crushing result.

2 Crushing for example 100 grams of ocher from Morocco in block with a cast iron mortar. Do not forget to wear a dust mask

4

5

3 Arrange all around the mortar a cloth or a waterproof rag will work especially if the pigment is toxic to prevent splinters from jumping and scattering during crushing.

6

The crushing is finished after 3

End of ocher grinding with cast

minutes, it is very fast. Note the

iron mortar. The powder is now

The powder is placed in the bowl of

powder which passed through the

sufficiently fine to be extrafine

the electric mill to grind it very finely.

fabric it is so fine.

powdered with an electric mill.


119

OCHRES AND EARTHS SPRAYING USE OF AN ELECTRIC MILL

8

7

Continue grinding for 1 minute. The mill is left to cool for 30 seconds

Initially we start the electric grinding 15 seconds

9 Finally, the pigment is powdered for about 2 minutes

13

10 The powdering with the mill is finished, the dust shall be allowed to settle before opening the bowl. Wear mask and gloves.

11 12.If the pigment is fine enough, it is possible to begin the purification by levigation, by preparing an Imhoff cone. 13.If the powder contains no impurities, an agate mortar is prepared for fine grinding with water to form paints.

12 Imhoff Cone Filled with water


120

FINE GRINDING OF PIGMENT POWDERS WITH WATER PRACTICAL USE OF AN AGATE MORTAR

1 Place 20 grams of pigment in an agate mortar, quantities are for demonstration, but it is possible to multiply them if you have a larger mortar.

2 10 ml of water are added, the grinding can begin.

4 3

Crushing the pigment of Morocco's red ocher with water, this make a creaky sound, because we crushes the grains of the pigment.

The upper part of the water/pigment mixture is removed with a syringe, here 10 ml to avoid overflowing, but also because impurities could be present, especially in the case of minerals.

6

5 The fine grinding is achieved for 5 minutes until the end of the creaky sound (characteristic of minerals and rocks) which means that the pigment is really very fine and able to constituting a quality paint with all binders.

The grinding is finished when the action of the pestle on the pigment no longer makes a characteristic sound of sand that is crushed. The pigment is suspended in water. The excess water must now be removed to recover the purified pigment.


RECOVERY OF PURE PIGMENT

121

Universal method for grinding a pigment with water, which constitutes a pigment paste that can be used with all techniques. This is a great time saver when making paints.

8 7

After removing the excess water, it remains the purest pigment, it is enough to mix it with a binder to constitute a painting, personally I wait that the water evaporates.

The water is removed with a a pipette or a syringe in order to recover the pigment more easily. The red ocher of Morocco pigment is ready (it is one of the natural ocher which possess the strongest red coloration, it also exists in blocks). The very fine powder is recovered in a flask in order to make it a paint at any time by simple mixing with any binder, but it can also be used like that on linen or cotton cloth as in the "Tüchlein" technique [11]. Despite of its inorganic nature this pigment has sufficient

coloring

power to dye a fabric without the addition of an additional binder, however, such works remain very fragile to abrasion

9 After 24 hours, all the water evaporated, scratching with a round knife and a brush to collect the pigment.

and shocks, ensure to protect them with a matte varnish or under a glass frame.

10


122

MINERALS POWDERING GRINDING MINERALS TO MAKE PIGMENTS

2 1

Replacing the mill bowl The grinding can begin.

100 g of azurite are placed in the bowl of an electric mill.

4 Let cool the mill for 2 minutes, then continue grinding azurite for 1 minute.

5

3 At first, grind the azurite for 15 seconds.

6 The powdering is finished after another 1 minute.

The spraying is finished, let the dust settle. Wear a mask and gloves before opening the bowl.

8 The azurite powder is fine and it appears blue, but if we grind it with oil in this state it would give dark green blue and not pure blue. It must be purified because it contains many impurities such as sand.

7

The transformation of azurite into A fine powder took 3 minutes.


LEVIGATION : DEFINITION AND USE

123

PURIFICATION OF MINERALS "Levigation" is the key word for the transformation of minerals into pigments. Once we have obtained a sufficiently fine grain, we must purify the mineral powders, in order to separate them - by means of an Imhoff sedimentation cone - all impurities, including soluble salts and other sandy parts. This operation is called "levigation" which comes from the Latin "laevigare", leviger, which means: "technique for separating the constituents of a powder with air or a liquid stream". It is the action of purification of minerals by water. There are different methods of levigation. There are various industrial processes of levigation, with air apparatuses separating the different grains; The levigation with successive tanks at different levels filled with water as for the purification of ochres and an handicraft procedure like this : we mix with water the powder of the minerals in an Imhoff sedimentation cone. The cone is swirled rapidly and stopped abruptly or the liquid is stirred with an agitator, the heavier pigment particles are going down while the lighter ones as well as the impurities will float. The cone is partially emptied in order to recover the purest pigment, so it is transferred from the top in order to remove the particles that are less pure, nevertheless colored. For an azurite, it is possible to obtain between 5 and 7 shades. It remains to crush these powders - with water in an agate mortar - they will become paints if mixed with a binder. The Imoff cone is a graduated transparent glass or Clear PVC container, 48 cm high, which can hold up to 1.4 liters of liquid. Imhoff Cone I use the Imhoff cone in the first stage of mineral purification to separate impurities and soluble salts from

Agate mortar and pestle

rocks, earth and minerals used to make pigments. Powders are obtained by crushing minerals or rocks in an iron mortar. The pigments must first be ground as dry as possible.

STEP 1

We fill the cone with a liter of tap water, then add up to 100 grams of minerals reduced to a fine powder, stir the mixture, rotate the cone on itself or use an agitator, wait until the mixture stabilizes and the heaviest pigment particles sediment, the lightest particles will float at the beginning, they are the less pure. The cone is gently emptied in a first tank to recover the impurities in order to leave the pure pigment at the bottom of the cone. Water is added to the line of 400 ml and step 1 is then start again until the water is no longer tinted by the impurities. Thus we recovered in different tanks several sediments of different shades and purities.

STEP 2

Grinding shall be performed with an agate mortar to purify as much as possible the mineral. The ideal would be to have a mortar as large as possible, but I will use a small model to explain my method. The different sediments collected in step 1 are ground with water in an agate mortar and taken with a 10 ml and a 100 ml syringe, with which the various sediments are retrieved by aspirating the substances that float after the grinding of the Pigment with water, until only the purest pigment remains at the bottom of the mortar. The pale shades impurities are the finest particles, they are recovered by aspirating the water + impurities mixture with the syringe immediately after the grinding. All what is float has to be removed from the mass in order to fully purifying the sediment which is none other than a purest colored substance which has been extracted from the mineral and which is called a "pigment ".

Mortar and pestle to grind the pigment with a binder.

porous porcelain mortar of 1 liter and pestle for crushing plants and organic matters


124

THE LEVIGATION PRACTICAL USE OF THE IMHOFF CONE

1

4

Fill the Imhoff cone with 1 liter of water

Let settle The mineral

2

The mineral is poured into the water

Wait 1-2 minutes for

Pour the first sediment

sediment

mark of 500 ml

5 the heavy parts to 6 into a tank up to the

mixture is stirred 3 The With an agitator

8 First sediment of azurite that is reserved, it will precipitate 7 while the other sediments are realized. You must fill as many tanks that we have of mineral to be purified, of impurities to be removed.


125

THE LEVIGATION PRACTICAL USE OF THE IMHOFF CONE

9

The Imhoff cone is emptied to finish the first sediment in order to leave the pure pigment at the bottom

10

In order to start a second sediment, water is poured to the mark of 400 ml and the mixture is then stirred with an agitator

13

11

And so on, this is the sediments. Water is put back in order to collected as much as necessary in order to remove all the greyish matter which constitutes the impurities.

12

step by step we have eliminated the first 2 sediments in vats, it is the most impure material, which has a greenish tone. It should be understood that azurite is one of the longest and most difficult mineral to purify, as it contains a lot of sandy matter.

Here is the dirty water that constitutes the impurities. It must be thrown into the sink, as it contains no coloring matter.


126

THE LEVIGATION THE FIRST 3 VATS GIVE 3 DISTINCT SHADES

14 The water is removed from the first sediment. If we want to keep the greenish-blue pigment, we let evaporated the water for 24 hours.

15 The water from the second sediment is removed in order to recover the pigment which can be further purified with agate mortar.

16

Here are the first 3 sediments. A clear blue begins to appear in the third tray. Most of the purification is almost complete.


127

THE LEVIGATION PURIFICATION OF MINERALS TO EXTRACT PURE PIGMENTS

17

Result of the last sediments, note how the one on the right is much purer and blue.

19 18 The purification with the Imhoff's cone will be finished after removing all the water from the cone. We can then begin the finer purification with agate mortar for a pigment of extreme purity.

We clearly see the sandy impurities mingled with the mineral. Here the water acts like a magnifying glass, so we can better distinguish the pigment and know when we must stop the levigation.


128

THE LEVIGATION - ...AFTERPART GRINDING THE MINERAL TO OBTAIN A MEDIUM QUALITY PIGMENT

20

After removing the water and the last impurities, empty the bottom of the Imhoff cone into a tray. Medium grade azurite is ready to be crushed.

23

10 ml of water are added then the mixture is stirred with the pestle, and left to sediment, the impurities which staying afloat are removed with a syringe, this sediment is placed in another mortar No. 2 , this is another shade of average quality.

22

21

We add 10 ml of water to grind the mineral as thinly as possible, slowly, 5 to 10 minutes.

50 g of pigment are placed in the agate mortar to start grinding.

24

25

We continue grinding the pigment for 1 minute (without adding water) and removing the water/pigment mixture staying afloat with a syringe, then we put it to the mortar No. 2, this is the result of the average quality.

Continue the grinding and the taking of the azurite pigment in average quality, add 10 ml of water, grind 1 minute and then remove what floats with the syringe and empty it in mortar N ° 2.

27 26 The water staying afloat is removed after grinding, it contains a portion of sandy matter. All the water which is removed must be placed in the mortar No. 2, made of porcelain or other, because in this water there is a blue pigment of average quality, but of a frank color.

Here is the mortar No. 2 and the moderately purified pigment, it is a full part shade, but we can continue to purify it to obtain a finer quality which has a shade of purest blue. This average grind can therefore give 2 distinct qualities, an average and a fine.


LEVIGATION THE FINE AND EXTRA FINE QUALITY

129

PURIFICATION OF MINERALS WITH AGATE MORTAR

28 we grind in agate mortar with 10 ml of water and then the staying afloat water is removed, this is another shade.

29 Azurite fine quality obtained with the N°27. If this fine quality is further ground with 10 ml of water, an extrafine quality is recovered by levigation.

31

32

This quality must be purified one last time to obtain an extrafine azurite.

Fine azurite which is purified by grinding and subsequent washing.

30 We will purify by levigation this

other grind to obtain 2 distinct qualities of blue, an average and a fine.

33

Thus, this quality of extra-fine blue is obtained by purifying the shade No. 31.

34

35

Fine and extra fine Azurite, the extra quality is deposited in another mortar and the fine quality in porcelain mortar No. 2, and so on according to the number of shades desired. A minimum of 2 mortars is required.

Azurite of extrafine quality which has been extracted from the previous baths. The purest quality has thus been obtained. Let the pigment to dry naturally in a flask. See the result as a dry pigment on the next page.


130

RESULT OF LEVIGATION FOR A QUALITY PIGMENT BOTTLING OF THE PURIFIED DRY PIGMENTS

3 azurite levigations, the extra quality is on the right, the fine quality on the left and the average at the center.

Extrafine Azurite 2016

Extra-fine red ocher from Morocco

3 levigations of azurite, the extra quality is on the left, the average quality in the center and the fine on the right.

Red ocher from Morocco extrafine on left and raw variety on right.

extra-fine Azurite lighter Extra-fine red ocher from Morocco

Extra-fine Azurite

These two pigments were used to make the photos of this article to explain how from a rock, a mineral, an ocher or an earth, the purest pigments are extracted with a little bit of patience.


COLLECTION OF 400 PIGMENTS 200 NATURALS MADE BY ME

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43 plant and animal pigments © 2018 David Damour

Collection of pigments in 2016 ©David Damour

Collection of pigments in 2008 ©David Damour

Collection of pigments in 2018 ©David Damour : on the left the pigments I make myself with plants and coccineal. In 2021 I have 200 naturals pigments made with plants at my atelier


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THE PIGMENTS The definition of a pigment proposed by the Association of Pigment Manufacturers (CMPA), in response to a request from the Inter Agency Committee on Toxic Substance Testing, was developed specifically to allow differentiation between a pigment and a dye. Reproduced here this definition in its entirety : "Pigments are colored in black, white or organic fluorescent particles and in the form of inorganic solids which are generally insoluble and are not physically and chemically affected by the substrate or vehicle in which they are incorporated. The pigments are generally dispersed in vehicles or on substrates to be applied, for example, in inks, paints, plastics or other polymeric materials. The pigments retain their crystal structure or particles during the colouring process. Due to the physical and chemical characteristics of the pigments, the different pigments and dyes in their applications, when a dye is applied, it penetrates the substrate in a soluble form, after which it may or may not become insoluble. When a pigment is used to color or opacify a substrate, these finely divided and insoluble particles remain entirely throughout the coloring process". In summary, a pigment is a pulverulent, coloring, insoluble and essentially physically and chemically unaffected material By the vehicle or the support. The use of natural pigments dates back to prehistory. Our ancestors used ochres, hematite, brown iron ore, manganese, and so on. ... these materials could flush to the ground and then "artist" ties these pigments with grease, resins, natural waxes or any other material that can act as a binder and that nature provides. Then, thanks to the discovery of the fire (about -450,000 years ago) and the domestication of it, the use of calcined soot of wood charcoal, residues from the combustion of various tree species, including scots

1 Natural azurite

pine, for the man to express his ideas by the realization of frescoes with precise graphics like those of the cave Chauvet discovered in 1994, located in France in the commune of Vallon-Pont-d'Arc, in the department of Ardeche, Which dates from the Aurignacian (with two dates of occupation of the site : between 33 and 29 000 years and in Gravettien between 27 and 24 500 years before thev Present Day); They are among the oldest rock frescoes, for now, until a future discovery!. Later, towards the end of prehistory, about 5,500 years ago, the development of writing, as we know it today, began in some parts of the world. There are many examples throughout the history of mankind of the use of natural pigments and the making of artificial pigments such as Egyptian blue and green which are among the first artificial inorganic pigments created by man. Indigo is certainly the first organic dye.

Chauvet Cave - Horse Panel BY Claude Valette via Wikimedia

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3

4

Cast iron mortar to crush the mineral

Azurite pigment ground in a mortar of agate

Azurite ground with gum arabic and apricot gum


THE PIGMENTS Thus, the history of pigments dates back to prehistoric rock paintings, which bear witness to the use of ocher, carbon black, hematite, brown iron ore and other pigments based on minerals or rocks, More than 30,000 years ago. (The date is just a benchmark, what counts are the components they used). We know from the literature that cinnabar, azurite, malachite and lapis-lazuli have been used in China and Egypt since the third millennium BC. The blue of Prussia was synthesized in 1704, it is the first pigment of that kind. Only one century later Louis Jaques Thénard produced his cobalt blue. High technological skills led to the production of chromium yellow, cadmium yellow, the creation of many synthetic iron oxides covering ranges of colours from yellow to black, orange, brown and violet ; Also include green chrome oxide and synthetic ultramarine. In the 20th century, major developments in chemistry led to the creation in 1936 of molybdenum red and in 1960 titanium nickel yellow. At present, new inorganic pigments are introduced on the market, such as vanadium bismuth and praseodymium/spinel zircon yellows, bismuth pigments based on zirconium oxide and cerium mixed or doped with transition metals; As well as samarium pigments, cerium pigments for the formulation of lead-free sulphide pigments, which

can be used as a replacement for cadmium sulphide and cadmium sulfoselenide pigments. Let us mention the white of zirconium, a very promising pigment, one of the last pigments to have been invented at the end of the 20th century. In 2005, world production of inorganic pigments was about 6 million tons, of which 2.4 million tons were for high-performance pigments, and about 700,000 tons of organic dyes in terms of world demand for paints for all 2000, it was about 20 million tonnes. We are in 2016, these figures have had to increase since then. This demonstrates the importance of pigments, which cannot be dispensed with in modern societies. Today, in 2016, there are about 600 inorganic pigments and more than 8,000 organic dyes listed in the Colour Index, which increases every year. All these inventions, which are nevertheless banal for the man of the 21st century, make it possible to highlight the influence and the importance of the pigments, ins and outs of all the colours that surround us. I invite the reader to a journey into the heart of the colourful raw material, from which are extracted so sublime powders tinted called "pigments", which will constitute after transformations, paintings high in colour on the palette of the artist painter.

Display stand for pigments for enluminure @ 2018 Damour David

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THE COLOUR INDEX CI The Color Index ™ International or C.I

It is a reference database, maintained jointly by the British Society of Dyers and Colorists and the American Association of Textile Chemists and Colorists. Printed for the first time in 1925, it is now exclusively published in digital form on the internet. So far (2016) there are approximately 27,000 products for a total of more than 13,000 generic names, including more than 8,600 chemically different coloring products for more than 40,000 trade names. The availability of a standard and universal classification system for pigments and dyes is useful and essential because it determines the contradictory historical, proprietary and generic names that are sometimes applied arbitrarily to colors. Thus everyone knows which pigments or coloring matters, it uses [76].

The Colour Index CI or abbreviated C.I

It is a generic and universal way to identify a pigment or a dye: 1. By its nature: Pigment, Dye or other C 2. By its color: white, black, blue, etc. ... I 3. By its Serial Number G 4. By its Constitution Number = CICN N

The first letter of the Color index corresponds to the nature of the pigment: There are 19 P = Pigment S = Solvant dye http://bit.ly/Solvent-Dyes N = Natural for natural dyes M = Metal for Metallic Pigments CA = Acid dyes http://bit.ly/Acid-Dyes CF = Food dyes CR = Reactive Dyes CV = Vat Dyes CD = Direct Dyes http://bit.ly/Direct-Dyes CB = Basic Dye http://bit.ly/Basic-Dyes FP = Fluorescent Pigments Azo Coloring Materials Dyes Textile Ingrain Dyes for Leather Developers Sulfur Dyes Condensed Sulfur Dyes Dispersed Dyes http://bit.ly/Disperse-Dyes Oxidation Dyes

The second letter of C.l is the color W for White

Bk for Black

R : Red - Rouge Y for Yellow G for Green

Br for Brown O for Orange B for Blue

V for Purple or Violet

The CIGN

This is the Generic Name assigned by the Color Index, it describes a commercial product : 1. by its nature 2. by its hue 3.a serial number : The serial number represents the chronological order in which the colorant types were registered by the Color Index, for example : Pigment Blue 29 or PB 29 = CIGN of the Lapis Lazuli Pigment Blue 31 or PB 31 = CIGN of the Egyptian Blue.

The CICN

It describes a product by its molecular formula (from 10000 to 77999). When a new molecule appears on the market, it is classified and a new entry is assigned to it with a number of five or six digits. Within each molecular category, each product is classified according to its chemical structure. Where possible, entries are classified according to their hydrogen function. When a product differs only by its metal or acid function, but also according to its crystalline modification for certain pigments; Thus a subdivision is made by adding another number separated from the first number by colon (:), example of Prussian blue = CI Pigment Blue 27: 1 = Alkali ferriferrocyanide

Writing the color index of Prussian Blue Nature P

Color B

Serial Number 27:1

CICN 77510:1

Abbreviated text of the Prussian Blue Colour Index : C.I PB 27: 1 77510: 1 which can also be written in full plain text : Colour index Pigment Blue 27: 1 77510: 1

Writing the color index of Lapis-lazuli Blue Nature

Color

Serial Number

CICN

P B 29 77007 Abbreviated text of the Lapis-lazuli Colour Index : C.I PB 29 77007 which can also be written in full plain text : Colour Index Pigment Blue 29 77007

So the Color Index cover and reflects 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11.

The generic name = CIGN The usual name The common, historical and commercial name The Constitution Number = CICN The constitution and the chemical formula The description of the shade Its opacity The light resistance The oil absorption rate The Toxicity Technical and chemical notes inherent in pigments and dyestuffs


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THE COLOUR INDEX CI CICN Chemical categories and range

12. Acridine 46000-46999 13. Amino ketone and hydroxyketone 56000-57999 14. Anthraquinone 58000-72999 15. Aza heterocyclic 50500-50999 16. Azine 50000-50499 17. Azoic acid 37000-39999 18. Oxidation bases 76000-76999 19. Benzoxazole 51500-51999 20. Carotenoids 40800-40999 21. Organic Natural Dyes 75000-75999 22. Diphenylmethane 41000-41999 23. Disazoics 20000-29999 24. Indamine 49400-49699 25. Indigoid 73000-73899 26. Indophenol 49700-49999 27. Lactone 55000-55999 28. Methine and polymethine 48000-48999 29. Mono azoic acid 11000-19999 30. Nitro 10300-10999 31. Nitroso 10000-10299 32. Oxazine 51000-51499 33. Phthalocyanine 74000-74999 34. Inorganic Pigments 77000-77999 35. Polyazoic acid 36000-36999 36. Quinacridone 73900-73999 37. Quinoline 47000-47999 38. Sulfur 53000-54999 39. Stilbene 40000-40799 = Fluorescent brighteners 40. Tetrakisazo 35000-35999 41. Thiazine 52000-52999 42. Thiazole 49000-49399 43. Triaryl methane 42000-44999 44. Trisazoic acid 30000-34999 45. Xanthene 45000-45999 Respective subgroups at this address : http://colour-index.com/cicn-groups-sub-groups

reactions and that there are no physical additives added to the final material, therefore it is pure. If this is the case, the dye or pure pigment responsible for the coloring of the final material is called "Essential Dye". The Colour Index is a very dynamic document in constant evolution that adapts to the progress of the analysis techniques and the complementary information desired by the users. It is now considered more critically, as are increasingly precise tools and advances in modern investigations. It is, in fact, a very sharp tool for research and knowledge of technical data. The Colour Index is therefore an ultimate and universal tool, indispensable for the painter and allows : 1. Know the precise chemical composition of a pigment or paint if the supplier indicates its reference. 2. To compare two pigments or dyes of the same family, but of different composition or natures : The cobalt blues or the ultramarine blues among them, the blue synthetic ash of the Azurite. 3. To recognize an authentic pigment of an imitation (which is not always noted on the commercial material) for example a natural yellow ocher of C.I PY 43 compared to a synthetic yellow iron oxide of C.I PY 42. 4. To distinguish a pure pigment compared to a mixture of pigments, which is not always easy to identify. 5. To keep up to date on the new pigments and dyes developed continuously.

To be affiliated to the Colour Index, a coloring matter, pigment or dye must be of the same chemical constitution and the essential coloring results must be obtained from a single chemical reaction or a series of several reactions from original substances. The definition also includes multi-constituent substances or process products intended to exclude substances obtained by simple physical mixing of several or two colorants or pigments in pulverulent form. Many commercial products contain, as well as the substance responsible for the color, quantities of other chemicals, generally they are additives intended to improve the pigment's application properties, such as dispersibility, flow and / or Resistance to flocculation. Dyes often contain large amounts of fillers. In all cases, the essential coloring material is the part of the material responsible for the color and excludes any additives. The Colour Index should be used to ensure that the original coloring matter of each dye or pigment results from a single chemical reaction or a series of Illustration © 2016 David Damour


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LIST OF REFRACTIVE INDICES OF PIGMENTS AND RAW MATERIALS The Refractive Index is compared to that of air, it allows to know the opacity and transparency properties of a pigment. The closer the Refractive Index is to that of the binder, therefore the smaller the difference, the more transparent the material will be in it. A very opaque material will therefore see its IR very far from that of the binder, whatever its nature. The greater the difference between the refractive index of the pigment and that of the medium in which it is dispersed, the more intense the light scattering. The angle of refraction relative to the angle of incidence in air is called the Refractive Index (represented by "n"). The Refractive Index is what makes a stick seem to flex when we put it into water. • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • •

Acetone ~ 1.36 Acrylic ~ 1.49 Aegyrine ~ 1.760 to 1.805 Air: 1.000 292 6 Albumin ~ 1.35 to 1.39 Alcohol ~ 1.329 Alkyd / Melamine (75/25) 1.55 Alumina White ~ 1.50 to 1.56 Aluminum hydroxide ~ 1.568 to 1.587 Amber ~ 1.546 Anhydrite ~ 1.570 to 1.614 Antimony Oxide ~ 2.09 to 2.29 Aquazol 200 ~ 1.52 Arabic gum solution ~ 1.344 Azurite ~ 1.730 to 1.85 Barite Green ~ 1.8 Barite White ~ 1.636 Barium yellow ~ 1.96 Beeswax at 74 ° C ~ 1.442 Bismuth-Vanadium yellow ~ 1.9 to 2.4 Bitumen ~ 1,635 Black Iron Oxide ~ 1.9 to 2.1 Black Magnetite ~ 2.42 Blue ash ~ 1.73 to 1.838 Bronze ~ 1.18 Burnt Sienna ~ 2.39 Butadiene Styrene Resin 1.53 Cadmium red ~ 2.64 to 2.77 Cadmium yellow ~ 2.35 to 2.5 Calcined Umber ~ 2.3 Calcite ~ 1.486 Calcium Carbonate 1.63 Canada balsam ~ 1.53 to 1.55 Carnation Oil ~ 1.477 Castor Oil ~ 1,479 Cerium Red PR 265 ~ 2.7 Cerulean Blue ~ 1.84 Chalk ~ 1.48 to 1.60 depending on the variety Chrome Yellow ~ 2.2 to 2.6 Chromium ~ 2.97 Chromium Oxide Green ~ 2.55 Chrysocolla ~ 1.575 to 1.598 Cinnabar ~ 2.819 to 3.146 Clay 1.65 to 1.80 Cobalt Blue ~ 1.74 Cobalt Green ~ 1.94 - 2.00 Cobalt Violet ~ 1.7 to 1.9 Cobalt Yellow ~ 1.70 to 1.75 Cochineal Carmine ~ 3.0 Copal from Congo ~ 1,545 Copper ~ 1.10 Copper Oxide ~ 2.705 crocoite ~ 2.31 to 2.66

• • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • •

Cyclomethicone D4 and D5 ~ 1.394 Dammar resin ~ 1.515 Diamond ~ 2.42 to 2.75 Diatomaceous earth 1.45 Dioptase ~ 1.64 to 1.71 Dolomite ~ 1.503 Egg white paint~ 1.346 Egyptian Blue ~ 1.63 Emerald green ~ 1.9 to 1.95 epidote ~ 1.715 to 1.797 Essence of Asp ~ 1.47 Essence of Turpentine ~ 1.46 to 1.48 ethanol ~ 1.3 Ethyl alcohol ~ 1.36 Fe2O3 ~ 2.4 Glass ~ 1.51714 Glauconite ~ 1.62 Glycerin ~ 1.473 Goethitis ~ 2.10 to 2.40 Gold ~ 0.47 Graphite ~ 2.70 Green Earth ~ 1.50 to 1.70 Green Earth of Verona ~ 1.68 Guanine ~ 1.85 Gum-Gut ~ 1.58 to 1.59 Hematite ~ 1.9 to 2.9 depending on the variety Indigo ~ 1.49 to 1.52 Iron Oxide ~ 2.918 Isoindole Orange ~ 1.7 Ivory ~ 1,540 Ivory Black ~ 2.5 Jarosite ~ 1.713 to 1.850 Jasper ~ 2 to 2.2 Kaolin ~ 1.55-1.56 Klucel ~ 1,337 Lamp Black ~ 2.1 Land of the Ardennes ~ 1.80 Lanolin or Suintine ~ 1.478-1.482 Lapis Lazuli and Ultramarine Blue ~ 1.5 Laropal K80 ~ 1.529 resin Lead Red ~ 2.42 Lead White ~ 1.94 to 2.10 Lead yellow tin ~ 1.9 to 2.1 Linseed Oil ~ 1,484 Lithopone White 30% ~ 1.84 Madder ~ 1.8 Magnesium carbonate ~ 1.509 - 1.700 Magnesium Silicate 1.65 Malachite ~ 1.65 to 1.90 Manganese black ~ 1.9 to 2.1 Manganese Blue ~ 1.65 Manganese Brown ~ 1.9 to 2.1 Manganese Violet ~ 1.8


LIST OF REFRACTIVE INDICES OF PIGMENTS AND RAW MATERIALS • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • •

Manila Copal ~ 1,544 March orange ~ 1.50 Mars Violet ~ 1.7 Mars yellow ~ 1.5 Massicot~ 2.52 to 2.62 Mastic Resin ~ 1.536 Mels Gray ~ 1.85 Mercury ~ 1.62 Methanol ~ 1.329 Mica ~ 1.60 Minium or Mine Orange ~ 2.40 to 2.42 Molybdenum Orange ~ 2.55 Molybdenum Red ~ 2.55 MS2A resin ~ 1.505 Naples yellow ~ 2.0 to 2.3 Natural Indian Yellow ~ 1.67 Natural Spinels ~ 1.715 to 1.725 Nylon ~ 1.53 Onyx ~ 1.486 Orpiment ~ 2.4 to 3.1 Oxidant Soy Alkyd ~ 1.52 to 1.53 Paliotol Orange ~ 1.71 Phthalocyanine blue ~ 1.5 to 1.7 Phthalocyanine Green ~ 1.7 Plaster 1.53 - 1.62 Polyurethane resin ~ 1.50 Pozzuoli Red ~ 2.5 Praseodymium yellow ~ 2 to 2.1 Priderite Yellow ~ 2 to 2.1 Prussian blue ~ 1.56 Quartz ~ 1.543 to 1.64 Réalgar ~ 2.46 to 2.61 Red Ocher ~ 2.75 to 2.95 Resin Regalrez 1094 ~ 1.519 Rosin ~ 1.525 Rubber ~ 1.5191 Rutile Titanium White ~ 2.71 Safflower oil ~ 1.476 to 1.4810 Sanitobre ~ 2.0 to 2.2 Sepiolite ~ 1.520 to 1.530 Shellac ~ 1.513 to 1.516 Shellsol® A ~ 1.4950 - 1.5040 Shellsol® D40 ~ 1.4250 to 1.4360 Shellsol® D70 ~ 1.4300 to 1.4500 Shellsol® T ~ 1.4240 - 1.4310 Siderite ~ 1.57 to 1.78 Sienna ~ 1.87 to 2.17 Silica ~ 1.45 to 1.49 Silver ~ 0.180 Smalt ~ 1.46 to 1.55 Smoke Black ~ 1.9 to 2.25 Soybean Oil ~ 1.48 Spinel Black ~ 2.5 Spinel phase browns ~ 2 to 2.2 Strontian yellow ~ 1.92 to 2.01 Sulfur ~ 1,960 Synthetic Indian Yellow ~ 1.69 Synthetic Spinels ~ 1,730

• • • • • • • • • • • • • • • • • • • • • • • • • • • • • •

Talc ~ 1.57 to 1.60 Titanium Nickel Yellow ~ 2 to 2.1 Titanium Orange ~ 2.5 Titanium White Anatase ~ 2.42 Tung Oil ~ 1.513 to 1.522 Ultramarine Red ~ 1.5 Ultramarine violet ~ 1.5 Umber Nature ~ 1.87 to 2.17 Van Dyck Brown ~ 1.62 - 1.69 Varnish in general ~ 1.52 Venetian balm ~ at 20 ° C ~ 1.5193 Venetian turpentine ~ 1,530 Verdigris ~ 1.55 to 1.9 Vermilion 2.81 to 3.15 Vine Black ~ 2.3 Vinyl Acetate Resin 1.47 Vinyl Resin ~ 1.48 Vivianite ~ 1,580 Volkonskoyte Cr203 <15% ~ 1.7 - 1.9 Volkonskoyte Cr203> 30% ~ 2.45 Walnut Oil ~ 1.480 Water ~ 1.3330 Yellow Ocher ~ 2.0 to 2.40 Zinc green ~ 1.7 Zinc Oxide 2.02 Zinc sulfide ~ 2.37 Zinc White ~ 2.01 Zinc Yellow ~ 1.84 to 2.01 Zirconium ~ 2.2 Zirconium White ~ 2.40

The Refractive Index- Illustration © 2016 David Damour

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HIGH-PERFORMANCE MODERN PIGMENTS The artist, through teaching and empirically, should be aware of the particular limitations inherent in each type of painting. When new applications or destinations are explored, as is often the case with art, it is essential to make tests to verify the physicochemical integrity of the final work in order to ensure that its quality is optimal. Numerous paint tests are performed and compiled by ASTM, an American organization that tests materials to standardize and make known their properties and qualities, and which you should consult for information. [84] It is important to note that there are standard ASTM specifications for different types of artists' paints, including acrylic emulsions, watercolor, gouache, oil, alkyd resins, etc. .... These definitions represent consensus among producers, consumers and other interested parties by the acceptable characteristics and performance of the materials. It should be noted that most industrial products have not been developed particularly for artists' paints. Thanks to the broad spectrum of existing types of paints and their possible uses, we are tempted to pick up any material or the materials provided by the industry and use them to make our works. Each artist will therefore have to make tests himself, in order to know these new materials. He can read the literature in order to use them in setting as stable as possible in the most balanced final result because the constraints of the industry are not the same as those of materials and paints for use in artistic works. Consider asking your suppliers for the "data sheets" of the products you use. I have written this book in order to guide my colleagues, the artists, in the labyrinth of so numerous and equally complex materials, substances and new paints . It brings the question to mind if one should not be a chemist to make quality paintings in this 21st century. I'm talking about Complex Inorganic Pigments (PICs), high performance pigments and rare earth pigments, because they have increased strength for easel painting. We are sure to use very stable pigments, compatible with all binders and pigments. Because of their universality, they are pigments of the first choice for the painter, but some of these pigments are not yet available at retail, but it will not be long. The category of pigments known as "high performance" refers to groups of a larger set of pigments, both organic and inorganic, which exhibit increased durability. Their most remarkable characteristics are their resistances to ultraviolet radiation (resistance to light), their thermal stabilities and their chemical resistances. Since they are excellent for the industry, why not enjoy them and use them in artistic painting? Many high performance organic pigments have suffi-

cient stability for long-term outdoor applications but are not as light-fast or heat-stable as the most durable inorganic pigments in the same family. Chromates and aluminum can make lead pigments more stable by encapsulating them with a layer of dense silica. Without this surface treatment, these pigments can hardly be considered to be highly efficient. It is difficult to summarize all the trends in such a diversified pigment industry, and some pitfalls exist. On the one hand, product management has acquired a much greater role in the chemical industry than before, it influences the technical approaches of companies and universities involved in the research and development of these high-performance pigments. On the other hand, the majority of highly performing pigments fall into the category of nanoparticles in the form of corpuscles having at least one dimension smaller than 100 nanometers (0.1 μm). The technique of nanoparticles is receiving intensive attention because of concerns about its possible toxicological effects for humans. This is why it is always necessary to wear a mask when handling such substances in the form of powder. A trend in research is directed towards the development of high performance pigments for improved efficiency in emerging technologies for digital printing, electronic display and mass dyeing for 3D printers, to name a few some. Many articles are written by the most competent chemists and practitioners of the pigment domain (see European-Coatings for example). Collectively, these researchers have hundreds of patents in their respective fields of competence and many of them convey their knowledge through conferences around the world. Their sagacity is equal only to their knowledge of the technical aspects that will influence the technological future of the dyestuffs industry. Their views and contributions will prove invaluable to the end user in this vast field of pigments and dyes. Painters are at the end of the chain, but this could change, I hope for the future, not borrowing pigments and dyes from other corporations, but participating in the decision-making process and drawing up with the chemists. The term "high performance pigment" (PICs) is more often used to denote inorganic pigments than organic pigments. One of the problems with high performance inorganic pigments is the limitation of available chemical components, so very few new compounds have been developed in recent decades. Most inorganic pigments are thus personified by the conventional substances already well known. On the one hand, the cost parameters in the manufacture of existing pigments are governed by ubiquitous competition and, on the other hand, the discovery and development


HIGH-PERFORMANCE MODERN PIGMENTS of new "high performance" inorganic pigments with enhanced qualities: Common inorganic chemical materials such as chromium, titanium dioxide, iron oxide and carbon are used. The progressive improvement of pigment performance in general is necessary, such as, for example, the achievement of a formulation that is safe for the end user [102]. In recent years the rule has been applied to the ecological and toxicological fields of "sustainable development" driven by laws, a more responsible attitude and a pressing desire to substitute a whole palette of "old pigments". This resulted in the abandonment of previously well known and yet very useful inorganic pigments such as lead red, lead molybdate and chromium orange. They are replaced by environment-friendly pigments (less toxic), which are considered to be highly performing. The development of new types of PICs is more than imperative and indispensable in the field of "efficient and targeted pigments" such as corrosion catalysts or optically reliable UV compounds[99].

THE DEVELOPMENT OF PICS

A NEW GENERATION OF PIGMENTS: PICS, COMPLEX INORGANIC PIGMENTS ALSO KNOWN AS MIXED METAL OXIDES (MMO)

THE DIFFERENT TYPES OF PICS

It is an important family of high performance pigments called "Complex Inorganic Pigments" or PICs. Chemically speaking, these pigments are crystalline synthetic metal oxides, the structure of which is identical to that of natural minerals. They are named complex because they contain several distinct metals (see Periodic Table on page 132). These complexes provide a range of metal combinations and in practice they provide a wide range of pigments for this family (see table on page 133) [91].

WHEN TO USE PICS PICs are used when the stability of the color of the paint film is paramount. These components are resistant to attack and dissolution by chemical agents and solvents, they do not bleed or migrate during application. They have a higher thermal stability of hundreds of degrees than organic pigments, and are not discolored by exposure to ultraviolet (UV) rays. In fact, these pigments absorb UV light without decomposition, which qualifies them as excellent UV absorbers, and they also have excellent opacifying qualities. Among the pigments available on the market, they are the most stable and the most durable and they are eminently performing.

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The PICs are made by calcination (strong heating in the presence of air) of mixtures of metal oxides and precursors (oxides such as metal salts, hydrates and carbonates). Calcination temperatures generally range from 650 to 1300 °C [111]. All raw materials decompose at relatively low temperatures to form metal oxides. This combination of oxides becomes reactive at higher temperatures. Ions are metals and oxides that become mobile and interdiffuse to create a homogeneous solid. The ions in the solid material then rearrange to a stable crystal structure which is determined by the presence of metals, the oxygen/material ratio (O / M) and the calcination temperature. The pigments thus obtained contract a new structure following calcination, they are then ground to obtain a specific particle size, then they are often washed and finally kneaded to homogenize the final mass of the pigment.

The most common types of crystal structures encountered are rutiles and spinels, with some other structures of some importance. Titanates have the largest volume of PICs used today, and the greatest consumption is rutile. Rutile titanates represent by far the largest class of PICs used. Chromium antimony titanate yellows (CI Pigment Brown 24) are the most widely used, followed by the yellow of nickel titanate antimony of CI Pigment Yellow 53, which has a yellow green shade with high coloring power. He has Excellent chemical resistance and very good external durability, it is light-fast and heat-stable. The manganese antimony titanate brown (CI Pigment Yellow 164) occupies a much smaller place, and the other categories a significantly lower fraction. The rutile PICs contain a substantial amount of titanium oxide, as the base oxide, in a range of 70 to 90% TiO 2 calculated by weight of pigment. Positively charged ions (cations) of Ni (II) nickel, Cr (III) chromium and Mn (III) manganese transition metals are responsible for the hue (products) while the colorless (reactive) ions Ti (IV) titanium , Sb (V) antimony, Nb (V) and W tungsten (VI) are present to maintain the metal oxide filler or level. The tints range from light yellow to dark brown [101].


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HIGH-PERFORMANCE MODERN PIGMENTS

THE ELEMENTS CONSTITUTING THE PICS[23]

The cobalt titanium greens are generally modified by divalent zinc Zn (II) and divalent Ni (II) nickel and oxides producing light green hues. The greens can be in the same color space as the green chrome (III) oxide and compete with them somewhat since they acquired the same durability characteristics. However, cobalt titanates (Co-Ti) are usually formulated to give cooler, brighter shades, some of which have more bluish shades, impossible to obtain otherwise. Cobalt titanium is more expensive because of the cobalt it contains (PG 50 77377). The iron titanates (Fe Ti) are formed from combinations of iron (II) and titanium dioxide TiO 2. These formulations are often modified by the addition of iron (III) oxide, zinc oxide (II) and aluminum oxide (III). Like the cobalt titanates, they have an inverted spinel structure. Iron titanate pigments produce bright yellow-brown tones with dark red-brown reflections. In many cases these pigments exhibit greater thermal stability than zinc ferrites or brown iron oxides and are generally used in paints for these characteristics (PBk 12 77543).

The magenta substances (round on black background) on the periodic table [116] show the elements that are responsible for the base shade. The elements in blue (round on a black background) on the periodic table are colorless and are used to balance the charge and give its color to the final pigment.

TITANATES WITH SPINEL STRUCTURE

Spinel titanates form a smaller group of pigments than rutiles. The proportions in which the various substances combine into spinel-like M3O4 are performed by reacting 2 units of metal oxide with 2 units of titanium dioxide = TiO2, and as metal oxides the divalent nickel = Ni (II), Cobalt Divalent = Co (II), the divalent zinc = Zn (II) or the Divalent Iron = Fe (II). These titanates have an inverted spinel structure, where a number of ions occupy two octahedral coordination sites in the network. The best known titanate qualities are green cobalt titanium PG 50 and titanium iron brown PBk 12.

2

Cl

Gold 196.966569

Mercury 200.592

I

10

Kr Krypton 83.798

Xe

54

52

Iodine 126.90447

Xenon 131.293

Po At Rn

Bismuth 208.98040

Polonium 209

86

Bi

Argon 39.948

36

35

34

33

Lead 207.2

Tellurium 127.60

Ar

Bromine 79.904

Pb

Antimony 121.760

84

Tl

Tin 118.710

Thallium 204.38

Selenium 78.971

Sn Sb Te 51

48

47

Pt Au Hg

Platinum 195.084

Indium 114.818

Arsenic 74.921595

Neon 20.1797

Chlorine 35.45

53

Iridium 192.217

In

Cadmium 112.414

80

Ir

Osmium 190.23

Silver 107.8682

Germanium 72.630

83

Gallium 69.723

Ne

18

9

8

S

Sulfur 32.06

85

Rhenium 186.207

Palladium 106.42

79

75

76

W Re Os

Tungsten 183.84

Rhodium 102.90550

78

Ruthenium 101.07

77

Technetium 98

46

45

44

43

42

74

Molybdenum 95.95

32

Zinc 65.38

82

Copper 63.546

50

31

30

Nickel 58.6934

49

Cobalt 58.933194

81

Iron 55.845

29

28

27

26

25

24

23 41

73

P

Phosphorus 30.973761998

F

Fluorine 18.998403163

Astatine 210

Radon 222

Rutherfordium 267

Dubnium 268

Seaborgium 269

Bohrium 270

Hassium 269

Meitnerium 278

Darmstadtium 281

Roentgenium 281

Copernicium 285

Ununtrium 286

Flerovium 289

Ununpentium 289

Livermorium 293

11

8

11 7

11

6

11 5

11

4

11 3

11 2

11 1

11 0

9

10

10 8

10 6

10 7

Rf Db Sg Bh Hs Mt Ds Rg Cn Uut Fl Uup Lv Uus Uuo 10

Ununseptium 294

Ununoctium 294

Actinium 227

Thorium 232.0377

Protactinium 231.03588

Neptunium 237

Plutonium 244

Americium 243

Curium 247

Berkelium 247

Californium 251

Thulium 168.93422

Ytterbium 173.054

Lutetium 174.9668

Es Fm Md No Lr

Einsteinium 252

Fermium 257

Mendelevium 258

Periodic Table of the Elements of All Pigments and in particular Inorganic Pigments Complex PICs of Mixtures of Metal Oxides MMO and Pigments of Rare Earths Illustration © 2016 David Damour

71

69

70

67

68

Erbium 167.259

Nobelium 259

10 3

96

97

Np Pu Am Cm Bk Cf

Holmium 164.93033

10 2

Dysprosium 162.500

10 1

Terbium 158.92535

66

65

Gadolinium 157.25

10 0

Europium 151.964

99

Samarium 150.36

64

63

62

60

U

Uranium 238.02891

Promethium 145

95

Ac Th Pa

Neodymium 144.242

94

Praseodymium 140.90766

93

Cerium 140.116

61

La Ce Pr Nd Pm Sm Eu Gd Tb Dy Ho Er Tm Yb Lu

Lanthanum 138.90547

92

88

Elements of Rare Earth Pigments of the 21st century

Manganese 54.938044

59

Actinoids

Tantalum 180.94788

Silicon 28.085

O

Oxygen 15.999

17

Si

7

6

Al

N

Nitrogen 14.007

16

ACTINIDES

Carbon 12.011

15

POOR METALS

C

Boron 10.81

Cr Mn Fe Co Ni Cu Zn Ga Ge As Se Br

Chromium 51.9961

91

89-103

226

Radium

Hafnium 178.49

5

Ra

Niobium 92.90637

58

Fr 223

B

Hf Ta

10 4

Lanthanoids

87

Barium 137.327

Francium

LANTHANIDES

Zr Nb Mo Tc Ru Rh Pd Ag Cd

40

57-71

Caesium 132.90545196

V

Vanadium 50.9415

Zirconium 91.224

72

56

55

Cs Ba

Y

Yttrium 88.90584

Ti

Titanium 47.867

57

37

38

Strontium 87.62

Scandium 44.955908

89

Calcium 40.078

22

Ca Sc

Rb Sr Rubidium 85.4678

NOBLE GASES

TRANSITION METALS

Aluminium 26.9815385

21

K

Potassium 39.0983

ALKALINE EARTH METALS

Magnesium 24.305

39

19

Sodium 22.98976928

20

11

12

Na Mg

He Helium 4.002602

14

COLORLESS USED TO BALANCE THE CHARGE AND MODIFY THE COLOR SHADES OF THE FINAL PIGMENT

Beryllium 9.0121831

ALKALINE METALS

13

Be

METALLOID HALOGEN

98

4

3

Li

Lithium 6.94

NO METALS

5

ELEMENT THAT IS RESPONSIBLE FOR THE BASE COLOR

1.008

90

1

H

Hydrogen

Lawrencium 266


141

HIGH-PERFORMANCE MODERN PIGMENTS

32 COMPLEX INORGANIC PIGMENTS PICS AND HIGH PERFORMANCE PIGMENTS

Cobalt Green Titanium PG 50

OTHER TITANIUM-BASED PICS

The titanium-barium nickel yellow is the only other important category of titanate pigment, in addition to those already listed. The term "Priderite", as well as for spinel and rutile, refers to the crystal structure of the latter. These pigments provide a lighter hue of slightly green yellow, which is generally common for titanium nickel yellow, with the exception of its other properties are similar to those of other PICs. The basic formula of priderite yellow is : 2NiO × 3BaO × 17TiO2 (PY 157 77900).

Chemical

Color Index

Hue

CoAl CoCrAl

PB 28 77346 PB 36 77343

Spinel Spinel

(Zr, V) SiO4 CoZnAl FeCr

PB 71 77998

Blue Blue-green to teal Turquoise

PB 72 77347 PG 17 77288

Dark blue Green black

CoCr CoTi NiSbTi ZnFe BaNiTi NiNbTi CrNbTi

PG 26 77344 PG 50 77377 PY 53 77788 PY 119 77496 PY 157 77900 PY 161 77895 PY 162 77896

CrWTi MnSbTi

PY 163 77897 PY 164 77899

Dark green Green Yellow green Brown Yellow green Yellow green Yellow orange Orange Brown

Spinel Hematite corindon Spinel

NiWTi MgFe CrSbTi

PY 189 77902 PBr 11 77495 PBr 24 77310

ZnFe ZnCrFe FeCr FeCr

PBr 31 77496 PBr 33 77503 PBr 29 77500 PBr 35 77501

MnNbTi MnTiCrSb

PBr 37 77890 PBr 40 77897 PBr 45 778965 PBk 12 77543 PBk 23 77865

MnWTi Pigment brown PBr 24

FeTi SnSb FeMn CoCrFe CuCr CoFe NiCrMn FeMn

Chemical Type Titanium Yellow Nickel PY 53

Yellow Red-brown Yellow orange Brown Brown Brown-black Brown

Structure

Spinel

Spinel Rutile

Spinel Priderite Rutile Rutile Rutile Rutile Rutile

Spinel Rutile

Spinel Spinel Spinel Spinel

Brown

Rutile Rutile

Brown

Rutile

brown-yellow

Spinel

Grey

Cassiterite

PBk 26 77494 PBk 27 77502

Black Black

Spinel Spinel

PBk 28 77428 PBk 29 77498 PBk 30 77504 PBk 33 77537 Colour Index Pigment

Black Black Black Black Hue of the pigment

Spinel Spinel Spinel Spinel Structure of Pigment


142

HIGH-PERFORMANCE MODERN PIGMENTS ALUMINUM-BASED PICS

PICs that contain aluminum oxide, Al2O3, or alumina as the colorless base oxide are called aluminates. They almost always use the coloring oxide of the divalent cobalt (II) = CoO oxide. All these pigments adopt the crystalline structure of spinel and possess shades in the range from blue to teal blue PB 36 77343 of general Chemical Formula = Co (Alx, Cr1) 204. These pigments can also be modified by zinc, magnesium and titanium to make up a whole range of greener blues and teal blue shades.

PICS BASED ON CHROME AND IRON

A large number of PICs contain transition metal oxides in varying amounts of a colorless base oxide. The pigments listed in the table on page 132 use either trivalent (III) chromium green, trivalent red iron oxide (III), or a combination of both as the base. They are called chromites or ferrites, for the chromium and iron bases they contain respectively. Most have a spinel structure and sometimes other important structures such as corundum and hematite.

Blue Pigment PB 36 77343

Brown Pigment PBr 35

PICS BASED ON COBALT AND ALUMINUM

These are combinations of cobalt oxide and aluminum oxide to obtain a spinel structure. They give blue cobalt aluminate spinel, CI Pigment Blue PB 28 77346 (CoAl2O4). Variations of this pigment with Blue Pigment PB 72 77347 (Co, Zn) Al2O4 include modification with divalent zinc (II) Zn, magnesium oxide MgO, titanium TiO2 and lithium oxides Li2O a darker blue, but with very bright shades; If modifiers such as lithium and titanium are added, turquoise blue pigments are obtained. The cobalt blues commercially available are very durable pigments. They have excellent chemical and thermal stability and can be used in aggressive and outdoor environments without the risk of discoloration. The only disadvantage of these blues is that they are poor UV absorbers compared to other complex inorganic pigments.

Blue Pigment PB 28

BLACK PICS

There are 3 types of chrome and iron blacks, as well as a black of tin. The black 23 made of tin oxide (IV) and antimony oxide (V) has a cassiterite structure. The blacks containing copper are black PBk 26 and black PBk 28. Varieties containing cobalt include pigments PBk 27, PBk 29 and a nickel black, PBk30. All these blacks have spinel structures except PBk 23. Copper blacks are more widely used because they are excellent pigments. Cobalt and nickel blacks are only used in applications where their specific properties are required. Copper/chromite black (pigment PBk 28) is a spinel based on copper (II) and chromium oxide green (III), with a general formula CuCr2O4. The presence of copper slightly deforms the network of generally cubic oxides, while pure copper chromite is a tetragonal spinel. The modifier most often used for this black is manganese which is present in many commercially available qualities. Iron and molybdenum can also be used as modifiers. Copper chromite is more widely used for black PICs. This black PBk 28 offers a good shade of jet (a shiny black), excellent durability and heat stability up to 1000 °C. It is also an excellent absorber of UV, it offers a good opacity UV for the systems that use it.


HIGH-PERFORMANCE MODERN PIGMENTS Since they are chemically stable, copper chromite blacks are not subject to photocatalytic, whereas they are decomposed in the presence of white titanium dioxide. For this reason, dark grays and durable paints are often formulated using such blacks. High temperature cooking systems such as silicone paints and glass enamels use copper chromites to make deep grays and blacks. When blacks with greater thermal stabilities than copper blacks are required, cobalt blacks are used. Oil absorption rate is about 18%. They are described as pigments having the respective colour index CI PBk 29 and PBk 27. The divalent nickel oxide (II) is the most commonly modifier used. Since they contain a significant amount of cobalt, they are significantly more expensive than other black PICs.

Black Pigment PBk 28

BROWN PICS

There are three commercially important groups of ferrites and chromium browns. The former are pure ferrites defined by CI Pigments Brown 11, Brown 31, and Yellow 119, followed by mixed chromite / ferrite browns which are Brown pigment 33 and PBr 35. These are all spinels. The third type is represented by pigments mixed with iron and chromium. These pigments adopt one or the other structure of hematite or corundum. Spinel ferrite pigments containing pure zinc, C.I. Pigment yellow PY 119 and Brown PBr 31, or magnesium CI Pigment Brown PBr 11, provide shades of light brown yellow to light brown red. Iron-zinc pigments and, to a lesser extent iron-magnesium pigments, are widely used as heat-stable pigments for thermoplastic materials.

Manganese Black Pigment PBk 33

Their high cost price limits their use for porcelain and enamels which requires high thermal stability. The only important nickel black is described as PBK 30 pigment, it has a distinctive blue shade and excellent coloring power. The commercial qualities are generally modified with divalent and trivalent manganese oxides Mn (II) and Mn (III). These pigments are somewhat more heat stable than copper blacks, but less heat stable than cobalt blacks. These pigments are often used for their reflective infrared (IR) properties.

Pigment brown PBr 33

143


144

HIGH-PERFORMANCE MODERN PIGMENTS The mixed chromium-iron pigments of C.I PBr Brown 33 and PBr Brown 35 provide darker browns than the pure ferrites, covering a range of reddish brown to a shade close to black. These products are mainly used in plastics and paints to provide stable pigments to heat. In addition, Spinel Brown has good IR reflectivity properties, it is used at low temperatures in the manufacture of plastics and paints. Pigments containing only iron (III) and chromium (III) oxides in the ratio of manganese elements: M2O3, are identified by CI Pigment Green 17 or C.I. Pigment Brown 29. These two descriptions refer to the same type of pigment in the Color Index and their names may be used interchangeably. These pigments are not spinels, although they adopt either the structure of the corundum or the structure of the hematite. They are dark brown-red with an almost black hue. The primary characteristic of these pigments is their good IR reflectivity. They generally have a higher IR reflectivity than other PICs, whose IR reflections are dark. These browns and blacks are mainly used to prepare dark, durable paints and little heat build-up.

Common modifiers include aluminum, titanium, magnesium and zinc oxide. The cobalt (II) ions in the spinel are tetrahedral coordinated, providing a green base of chromium oxide with a bluish tint. Generally, the colors range from light blue to dark green. Intensive use of cobalt-chromium greens is important in camouflage applications. In the region of near infrared (IR) (700 to 1000 nm), this pigment has a reflectance similar to that of certain natural media. Chromium cobalt pigments have been found useful in the preparation of greenish pigments which correspond to ambient infrared signatures.

Blue de cobalt greenish PG 26

Pigment brun PBr 29

CHROME-BASED GREEN PICS

There is a chromite green pigment in this class. It is a green of chromite cobalt, C.I. Pigment Green PG 26 77343 (14% oil absorption rate). This pigment has a spinel structure based on cobalt oxide and divalent green chromium oxide (II), of general formula CoCr2O4.

Pigment vert PG 26

Ferro® website where you will find a data sheet for each high performance pigment, which I just mentioned: http://bit.ly/2bq9AHK


145

THE RARE EARTH PIGMENTS

Cerium oxide IV

Polishing Powder Optics with cerium

Cerium oxide CeO2

Black cerium sulphide

Light yellow cerium

Cerium red pigment red 265

Cerium oxide

Cerium Ultrapure on argon

By Materialscientist via Wikipedia

Cerium oxide(IV)

Cerium ammonium nitrate

Sulphide of Cerium By BXXXD via Wikimedia

Cerium pigment

Polishing Powder Optics with cerium

Cerium oxide (IV)

Sulphide of Cerium III à 80%

Neodymium oxide


146

THE RARE EARTH PIGMENTS The rare earth metals are elements of line VI of the periodic table of the lanthanide family. Contrary to their designation, rare earths are very widespread, their agglomeration in the earth's crust is of the order of 0.016%, ie as high as zinc, 10 times more than lead, and 1000 times Plus the money. Cerium is the 26th most abundant element and it is the most abundant rare earth metals, the two most rare being thulium and lutetium. It is a gray metal that reacts easily with other elements. Cerium was the first rare earth element to be discovered in 1839 by the Swedish chemist Carl Gustaf Mosander (1797-1858). Mosander was studying a new rock that had been discovered outside the town of Bastnäs, in Sweden. He named this new element "Cerium", in honor of the asteroid Ceres, which had been discovered in 1801. Cerium is found in the minerals of allanite, bastnaesite, hydroxyl of bastnaesite, monazite, rhabdophane, synchysite and zircon. [90] Only a few "high performance" inorganic pigments are now available (retail) for their high thermal, chemical and UV stabilities in a range from yellow to red, such as cadmium sulfoselenide, lead molybdate and bismuth Of vanadium which they advantageously replace.

Cerium Ultrapur under argon, 1.5 grams Materialscientist via Wikipedia

Density : 5 Kg / l Mohs Hardness : 4-5 Bulk density : 0.8 g / cm3 Typical particle size (μm) : 0.8 to 1.3 Temperature stability : 350-400 ° C Refractive index : 2.7 Absorption of oil : from 20 to 28% Cerium structure By Benjah-bmm27 via Wikimedia Commons

PIGMENTS WITH CERIUM SULPHIDE. THERE ARE THESE 4 PIGMENTS Sulfide of Cerium Light Orange. Chemical formula : Ce2S3·La2S3 Colour Index Pigment Orange CI PO 78 77285 : 0 Sulfide of Cerium Orange. Chemical formula : Ce2S3 Colour Index Pigment Orange C.I PO 75 77283 : 1 Sulfide of Cerium Red Chemical formula : Ce2S3 Colour Index Pigment Red C.I PR 265 77283 : 2 Sulfide of Cerium Red brown Chemical formula : Ce2S3 Colour Index Pigment Red C.I. PR 275 77283 : 0

Example of PR 265 Features

This pigment is given for strength for about 50 years, its resistance to the weather is high. It can advantageously replace cadmium red, molybdenum red, red iron oxide, in this case red pigments 122 and 254.

Description of Cerium Sulfide Pigments

Cerium sulphide is a kind of mineral pigment powder of yellowish red to light orange. Cerium sulfide pigments were developed in 1996 by Rhodia®, to be used in many coloring formulations. Cerium sulphide has powerful and vivid colors. These pigments are bright, have a high resistance to heat, light and weather. They benefit excellent hiding power, non-migratory and not bleeding, and they respect EU environmental directives.


147

THE RARE EARTH PIGMENTS FORMULATIONS WITH OTHER RARE EARTHS

By introducing an alkaline element of lithium or sodium in small proportions, the dark red color turns into a red to a bright orange. The color of these cerium-based compounds can be further modified by introducing fluorine. The resulting crystal lattices are 2-dimensional, composed of rare earth fluorinated sulphides and are rendered more stable in acidic environments and more temperature resistant than their sulphidated homologues.

Cerium oxide CI 77280

PREPARATION OF CERIUM SULFIDE PIGMENTS IN 3 STEPS

By partially replacing cerium with another rare earth such as samarium in small proportions, intense red pigments are obtained. Fluorinated samarium sulfides, as well as their sulfur homologues, also produce intense yellow colors. Their composition has a samarium purity of more than 99% relative to the other rare earths and contains at least one alkali or alkaline earth element, at least part of which is included in a crystal lattice of said sesquisulphide, while the cerium content is Less than 1%. Cf. Rhodia [93]

1. Synthesis of a Precursor Based on Cerium

An acidic solution of a cerium salt is converted by a liquid process using a reactive cerium precursor. At this stage, the alkali metal and / or alkaline earth metal salts can be added depending on the target color. The resulting precipitate does not yet have a hue and it is then necessary to convert it into a colored sulphide.

2. Sulfurization of the cerium precursor

The transformation of the cerium precursor into a colored sesquisulphide is performed at elevated temperatures (between 700 and 1100 ° C.) in a sulfurizing atmosphere. The resulting colored sesquisulphide is then cooled to room temperature. The lower the oxygen supply, the clearer the hue of the pigment.

3. Final treatment

Once the mass is tinted, it is reduced to powder in order to break up any agglomerates that may result from the sulfurization process. This step is necessary to reveal its pigmentary nature. A surface coating is then applied to the Ce2S3 particles by a wet process in order to increase the stability of the pigment and to optimize its compatibility with the final matrix. The coating may be inorganic or organic. Finally, the pigment is filtered, dried and sieved before its packaging.

Cerium red


148

THE RARE EARTH PIGMENTS APPLICATIONS OF CERIUM PIGMENTS

Red cerium sulphide can replace reds of cadmium and other organic and inorganic pigments that contain heavy metal elements. In the cosmetics industry red cerium sulphide can replace red iron oxide, as well as organic reds, it is used in all kinds of resins, plastics, high quality varnish, high paints Quality coating, non-stick coatings, fluorocarbon coatings, automotive coatings, coil coatings and marine coatings, with high temperature resistance, lightfastness and weather resistance, but is also used in red ceramic glazes in order to enhance their colors. Because it contains rare earths, the effect of red cerium sulfide is magnificent, and it can be used with all kinds of materials because it has much better qualities than other pigments of this color.

These compounds when applied by immersion improve the corrosion resistance and the adhesion of the paints. [91] The cerium sulfide pigments have a covering power and a relatively high opacity, similar to cadmium pigments. They can be used alone or in combination with other pigments and dyes to obtain orange and red tones. They are also used successfully as shading pigments in order to obtain pastel shades and beige tones. The cerium sulphide pigments can be readily dispersed in a variety of polymer resins such as plastics, but also with polyurethanes. They are highly dispersible as well as non-powdery, they are not sensitive to migration when dispersed in a polymer matrix and composite materials (thermoplastic, thermosetting, elastomeric materials). When combined with other pigments and dyes, cerium sulfide pigments can even improve the dimensional stability of the resulting composition, for example with high density polyethylene and with polypropylene. Cerium sulphide pigments also have a minimal effect on mechanical properties, such as shock resistance.

HUES [gamma (γ) forms] OF MARKETABLE RARE EARTH PIGMENTS IN THE NEAR FUTURE [88] Rare earth metals in powder form

CHARACTERISTICS OF PARTICULAR APPLICATIONS Cerium pigments are currently used in paints and varnishes, technical plastics, ceramic staining and packaging, where high opacity, thermal stability, lightfastness and no warping are still difficult to obtain with mineral pigments.

The latter compounds have excellent performance, but their toxicity is debatable to the environment. Thus, due to changes in legislation and government regulations, there is an increasing need to develop new classes of inorganic pigments that are both non-toxic and ecologically irreproachable, while preserving or even surpassing the optical, thermal And chemicals of the current high performance pigments. In addition, the use of rare earth salts of cerium Ce(NO3)3, lanthanum La(NO3)3 and sulfur bis-silane as substitutes for chromate coatings for galvanized steel has been proposed.

La2S3 Lanthanum sulphide

Yellowish white

Ce2S3 Sulphide of Cerium

Dark Red

Dy2S3 Dysprosium sulfide

Orange

Pr2S3 Praseodymium trisulfide

Green

Nd2S3 Neodymium sulphide

Light green

Gd2S3 Gadolinium sulfide

Ochre

Tb2S3 Terbium sulphide

Light yellow

InCl3 YCl3 Indium yttrium

Blue

The understanding by chemists and industrialists of the properties of lanthanide sesquisulphides, permitting the addition of alkali metals and / or alkaline earth elements, to widen the range of cerium sesquisulphides from light orange to reddish.


THE RARE EARTH PIGMENTS This chemical modification of the Ce2S3 gamma phase makes it possible to balance it at less than 800 ° C., which makes it easier to produce variously colored pigments. The NEOLOR™ cerium sulfide pigments of the Rhodia® brand are almost completely insoluble in water and their cerium ion does not, in fact, have any acute or chronic toxicity. [71]

PIGMENTS FOR THE FUTURE

Because cerium sulfide pigments have good thermal stability, excellent lightfastness, good opacity and dispersibility, they are the most promising pigments in the future as the successors of a whole family of colored materials consisting of heavy metals such as lead, cadmium and chromium. The rare earth sulphide materials have attracted much interest in recent years, mainly because of their very interesting optical and magneto-optical properties. The rare earth and sulfur elements combine to form a wide range of compounds such as sulfides or oxysulphides. Among them, sesquisulfides seem to have the best potential from the moment when the color is paramount. Cerium sulfide is the most promising when the hue and purity of the pigment is crucial.

Cerium oxide IV CI 77280

A new Blue created in 2016 Indium/yttrium/manganese PB86

Cerium Red Ce2S3

Cerium Sulphide BY Bxxxd via Wikimedia

149


150

CONVENTIONAL INORGANIC PIGMENTS

Display of pigments @ 2016 Damour David. From left to right : Chrysocolle - Indigo of Morocco - Cobalt blue - Spinel blue - Dark green cobalt blue - Manganese blue - Phthalocyanine Blue - Unpurified Azurite - Ultramarine Blue - Azurite N ° 1 - Emerald Green - Malachite

Display of pigments @ 2016 Damour David. From left to right : Lead White - Orange Mine - Gum-Gutte - Natural Orpiment - Golden Ocher - Yellow Verdaccio Titanium-nickel yellow - Strontian yellow - Ultramarine blue - Azurite N ° 1 - Malachite - Emerald green


151

BLUE PIGMENTS

Smalt

Blue Ploss

Prussian Blue

Chrysocolla

Cobalt Blue Turquoise PB28

Vivianite

Synthetic Azurite

Egyptian Blue

Smalt

Manganese

Spinel blue

Egyptian Blue

light ultramarine

ultramarine very light

Ultramarine extra dark

Blue spinel zirconia

Lapis-Lazuli

Blue Cerulean

Cobalt Blue

Aerinite


152

BLUE PIGMENTS The Lapis Lazuli Blue or natural ultramarine

Also known as "Painters Flowers", armenion, lapis armenus. Its name comes from the Latin lapis : stone and Persian "lazur" or "lazaward": blue. Color Index Pigment Blue PB 29 77007 No Toxicity Hardness: 5.00 to 5.50 Density: 2.38 to 2.45 Refractive index: 1.477 to 1.484-1.5 depending on the sample. Oil absorption rate : 36% Lapis-Lazuli is a sodium aluminosilicate containing sulfur and chlorine. Chemical Formula 3Na2O.3Al2.6SiO2.2Na2S Lazurite occurs in mass or in grains. The Lapis-Lazuli name is given to the mass lazurites containing the colored principle. The Lapis-Lazuli is a semi-precious rock, not a mineral (we makes jewels and ornaments with it), whose microscopic elements are very well distinguished, it is a mixture of white dolomitic limestone, pyroxenes and clear amphiboles. The meta somatic limestone rocks (exchanges between a rock and a solution, or between two rocks of different compositions) constitute the bedrock of the lazurites with impurities and traces of pyrites ("the gold of the fool" because of its resemblance to Gold) and iron, magnesium, potassium and water H2O. Lapis lazuli was used as a pigment in Europe from the Middle Ages. The first trustworthy information about the lapis comes from Marco Polo (1254-1324), because he was entrusted with important responsibilities by the "Tatar Koubilai Khan". Marco Polo visited the lazurite deposits in the province of Badakhstan in Afghanistan, describing the mines and mining of ore in his "livre des merveilles", where he recounts his trip to Asia. The lapis-lazuli is also found in Chile ( sells this quality). Its coloring and covering power is very low in oils, as these have a refraction Index too close to Lapis-Lazuli (1.477 to 1.484). It is best to use it in aqueous techniques to develop its beautiful shade. This pigment is really beautiful, it is an incomparable blue. It requires by long levigation of preparations from the raw rock. to gives up to 5 shades (from the purest blue to the bluish gray, see photos). It is very stable to light, but it is dissociated by acids by evolving hydrogen sulphide. It is the second most expensive pigment in powder form in the history of painting : € 18,000 per kilogram, which is why it is better to prepare it yourself. When we thinks that King Charles I of England (1630) offered 227 kg (500 pounds) of Lapis-Lazuli to the painter Anthony Van Dyck, we remains pensive [18]. Van Dyck returned to England in 1633, where he was ennobled, and made chief painter of the English court. He was paid £ 200 a year, while a simple farmer earned £ 20 a year. We so realize the value of the Lapis-Lazuli at that time. The lapis lazuli is compatible with lead white as well as with all techniques of painting except those whose binder is very acid like certain oils; Check the pH of your binders. ! (Overseas disease is rare).

Lapis lazuli rocks © 2016 David damour

Lapis Lazuli agglomerates

Lapis-lazuli says "Fra angelico" The purest quality By ©Attila Gazo from Master Pigment®

Lapis-lazuli 5th Levigation

Lapis-lazuli powder prepared by Levigation from the rock


153

BLUE PIGMENTS A SHORT HISTORY OF LAPIS LAZULI

A stone became semi-precious for a pigment with a strong symbolic connotation: The lapis lazuli carries luck and it is a sign of wealth. The connotation of "preciosity" makes this rock a matter with a strong symbolic and economic impact. The discovery of LapisLazuli objects for the period from the Neolithic to the Bronze Age is estimated at 29,976 units. This figure is considerable when we think of the value of Lapis-Lazuli. It is a much appreciated material, used mainly for trade. The history of Lapis-Lazuli begins in Neolithic times in Mehrgarh (Pakistan) where many pearls have been found [19]. The adornments became common only during the 3rd and 4th millennia BC [18-19]. The Lapis-Lazuli is highly symbolic, it is synonymous with positive and dynamic mysticism, charged with supernatural power, at the origin of the greatness and the immaterial power of the divinities. The Lapis-Lazuli is supposed to bring luck and protect against curses. The largest and most beautiful deposits of Lapis-Lazuli cited by Marco Polo in his book "livre des merveilles" are located in Badakhshan, at the Chaghai Mountains (the Afghan-Pakistani border) in Sar-eSang, a mountainous region about 3000 m Accessible by passes more than 6000 m, beyond the Hindu Kush, in the Pandjchir valley in Afghanistan [20]. The use of the lapis disappears, about 1500 BC.to reappear only in Phoenician and Roman times to gradually regain the Mediterranean via the Near East. The use of Lapis-Lazuli powder is very old. It is proved to be use as make-up by the women of Egypt. The same is true of its use in painting, in enluminure. The price of this raw material and the causes of supply shortages in the Middle Ages were studied : before the year 900, lapis lazuli was not used in Europe [Guineau 1986, Coupry 1999, Brown & Clark 2004]. Lapis-Lazuli was widely used by European painters of the 14th and 15th centuries, no doubt thanks to the enthusiasm of wealthy 'sponsors', the purchase price of the pigment was calculated separately when ordering paintings. The stability of lapis-lazuli up to 1100°C is proven, its tint is stable and fixed, like its synthetic homologue which supports heat of the order of 950 to 1100 ° C. The lapis-lazuli was the true precious (and not semiprecious) stone of the ancient East, signifying the essential symbol of the Near East and of Egypt, its possession was a sign of political and religious power. The lapis-lazuli continues to fascinate and today has a special place on the palette of the painter, as it is difficult to extract it in the form of powdered powder or pigment ready to use. Its preparation from the rock is arduous and does not let itself be apprehended as easily as other colored rocks. The lapis-lazuli has lost its precious stones status in favor of the diamond, Nevertheless, it is still a reference of choice for his beauty, purity and stability, for

the painter who wants to use it to embellish his works, because his presence has not gone unnoticed.

THE PURIFICATION OF LAPIS LAZULI

First, we choose 500 grams of lapis lazuli, which is marbled and of an azure tint, without any vein of gold and green. Break into small pieces and melt in a fire for a good hour in a container in which you have put a good distilled vinegar, place the pieces of lapis lazuli and leave them. Boil 1/2 liter of water with a little raw white honey in a small metal container. Skim until there is no more foam and let cool. When the entire material is well moistened, pass through a cheesecloth to collect it over a container. Grind the calcined lapis-lazuli with this water, and let dry in the shadows and not into the light or sun, which could damage its tint.

Once dry, prepare this paste for 500 g of Lapis SUBSTANCES

GRAMS

rosin resin

70

Mastic resin Beeswax

85 85

Melt with a little cold water, so as to obtain a homogeneous paste. Incorporate 33 parts of glycerin at the end into the paste, and allow to heat for a few moments, so that all the ingredients are incorporated with the previously baked pigment paste. Let the dough cool by spreading it on a marble or parchment paper and then make logs about 3 cm in diameter by 20 cm in length, let dry for 3 to 4 days. When the logs are dry, reheat them in hot water from 45 to 55 ° C for a few minutes while kneading them to incorporate the ingredients intimately. Let the Lapis loaves dry in the shadows for another 3 to 4 days. When you want to use azure, first make clear vine cedar laundry or, failing that ammonia (you can heat the loaves in warm water to soften them) and knead the dough in order to extract the lapis lazuli, until the material no longer rejects the purest blue pigment. Only the first extracts give the most beautiful pigment. Prefer the first extracts and put them aside otherwise you risk to incorporate sandy impurities into the sediment. This process makes it possible to separate the good substance from the poor quality. For 500 parts of lapis, 440 parts can be estimated, the remainder being a loss. Attila Gazo of Master Pigments prepares a beautiful lapis-lazuli in this way.


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BLUE PIGMENTS PURIFICATION OF THE LAPIS LAZULI COURTESY OF ATTILA GAZO OF MASTER PIGMENTS METHOD INSPIRED BY CENNINO CENNINI

Weigh 500 g of lapis + 85 g of beeswax + 70 g rosin resin + 85 g mastic resin

Pour the lapis into the wax - resin mixture

Constitute logs of lapis of 20 cm by 3 cm

Extraction of the lapis by kneading the dough in an alkaline water

Lapis-lazuli 1st sediment. Only the first extracts are the most beautiful, then the color becomes less pure.

Heat the mixture wax-resin

Stir mixture well to incorporate

Logs of lapis left to dry 3 to 4 days

Incorporate the Lapis-Lazuli into the wax-resin mixture

Pour the dough on the marble then let harden

Just before extraction of the lapis, heat the logs at 45 to 55 ° C, 15 min to soften them.

Extraction of lapis Note the difference in purity

1st extract of the extraction result of the purest lapis

Filtration lazuli, then set aside this sediment as the color of the powder is vivid.

Final result of lapis extraction call Fra Angelico. It is the purest and the most beautiful blue.


155

BLUE PIGMENTS Azurite

Also called mountain blue, German blue, vitriol blue. Colour Index Pigment Blue PB 30 77420 It is a natural copper carbonate of chemical formula : 2CuCO3.Cu (OH)2 ou Cu3 (CO3) 2(OH)2, often associated with the malachite with which it shares the Colour Index. Incompatible with lead, cadmium and sulfur with which it blackens. Toxicity of copper salts. Density: 3.8 Oil absorption rate : 26% Refractive index: 1.75 to 1.85 depending on the sample. Its deposits are found in several parts of the world, in deposits of secondary copper ore, often associated with malachite. The Egyptians used it already under the IVth dynasty, approximately between -2625 - 2510 BC. J.-C. Azurite was a pigment, very important until the seventeenth century. The artificial variety Na7Al6Si4O24S2 is made with kaolin, sulfur and sodium carbonate Na2CO3, It is a rather transparent pigment in oil, with which it degrades to become green or black with time. To avoid its decomposition, it must be used in mixture with Rubens medium which will protect it from external aggressions. It is preferable to use it in lean tempera or in enluminure, techniques in which Crushed azurite it develops its magnificent hue. By levigation of the natural mineral, we obtain up to 5 tones, this after long hours of purification. Azurite is very useful in the oil technique, underlayment for Lapis-Lazuli or other blues, but especially in enluminure.

Azurite Levigation Results

Different results of azurite levigation

Pure azurite after levigation purification

Smalt

Colour Index Pigment Blue PB 32 77365 Composed of silica (glass), potassium and cobalt SiO2Cox according to the proportion of cobalt it contains (between 2 and 18%). It is a distant cousin of cobalt blue. Word borrowed from the Italian Smalto ("enamel"), from the francique smalt ("enamel"). High quality raw azurite ©2016 David Damour


156

BLUE PIGMENTS Pliny mention in his natural history a blue glass (77. av J-C) under the term "sapphire". The smalt : Smaltino, was certainly invented in Italy in the late Middle Ages, around 1483 (Harley, 1982). Smaltite, a mineral called Skutterudite (Norway), was used to make smalt because it contains cobalt with a chemical composition (Co, Ni) As3, not to be confused with the pigment itself. It is one of the first artificial pigments of cobalt. Known by the Egyptians, but not as a pigment, it was used to make enamels and jewels. Used from the Renaissance, especially in the 16th and 17th centuries by Italian (Titian), Flemish (Rembrandt) and Spanish (Velásquez) painters, as a precoat for the Lapis-lazuli or as a filler for other blues. The smalt is prepared by baking a mixture of powders of cobalt salts and silica at about 1150 °C., the molten powder constituting a mass of glass of a deep bluish black color. The molten glass is ground into a fine powder and then purified. Velásquez used it as a filler with LapisLazuli. The smalt has noSmalt By Shisha-Tom torious siccative via Wikipedia properties, which is why it was used in mixture with other blue pigments, less drying. It is a very transparent pigment in oil, it is preferable to use it in aqueous techniques, in which it will moreover be more stable. It should not be too much crushed, otherwise it loses its color. Refractive index: 1.5

The Egyptian Blue

Colour Index Pigment Blue PB 31 77437 It is the first known synthetic inorganic pigment. It is a double copper and calcium silicate of Chemical Composition : CaCuSi4O10 It is prepared like the smalt, by heating quartz, with copper and calcium carbonate, at temperatures of up to 1,000 °C. Density: 3.0. Refractive index: 1.63 analysis by weight for

Silica SiO2 Calcium oxide CaO Copper Oxide CuO Iron sesquioxide Fe3O4

1000 parts 637 143 213 7

It is a pigment of Egyptian origin, 3000-2500 BC. J.-C., its use ceased towards the seventh century AD. J.-C., without knowing why. Its recipes are numerous and varied, but as a rule it is a mixture of fine sand with copper carbonate and chalk and a melting mixture such as sodium carbonate: Na2CO3. Blue is thus obtained by baking at temperatures of 851 to 1000 ° C. The molten and cooled mass is crushed and then reduced to powder. A remarkable solidity, it does not fear alkalinity, since it is Egyptian blue used in the fresco. It is currently in the catalog.

The Han blue

The Chinese made and used between 1045 BC and 220 AD, A copper and barium silicate BaCuSi4O10, copying Egyptian blue, exported to China through the Silk Road. By replacing the calcium carbonate with baryta heated between 20 and 48 hours, at 100 °C more than the Egyptian blue. It was used in ceramics and was widely used to decorate the famous terracotta warriors of the mausoleum of Emperor Qin.

Smalt

Zirconium vanadium Blue - Zircon Ceruleum Blue also called Blue Spinel and Blue lumière Colour Index Pigment Blue PB 71.77998 Artificial pigment, consisting of zirconium silicate and vanadium: (Zr, V) SiO4, of the spinel family and of the PICs. The zirconium vanadium blue is made by calcining at high temperature a mixture of zirconium (IV), silicon oxide (IV) and vanadium (IV) oxide in


157

BLUE PIGMENTS variable proportions to create a matrix in the form of zirconium Crystalline. Its composition may comprise, as modifiers, less than 5% of a combination of alkali and/or alkaline earth halides. It is a non-toxic but harmful pigment classified under transport number 3285, listed in class 6.1 of the hazardous products. Pigments are not made to be carried to the mouth. [75] The toxicological properties of this pigment have not been fully investigated (2009). Density: 4.62 Kg / l. It is a very stable pigment, compatible with all pigments and all pictorial techniques.

cial ultramarine blue, the price was awarded to him in 1828. This pigment has a remarkable stability, except in the acids, so that in recent years, the industrialists produce blues qualities coated with a low-emissivity SiO2 silicon oxide coating in order to improve the stability of the paints, making it possible to remedy any shortcomings found of the pigment. There are 4 to 7 distinct shades. It is a hydrophilic pigment, having an affinity for water in which it develops a beautiful tint. In oil, it is rather transparent hence a refractive index of about ~ 1.5. The coarse particles give a more red and deep blue while the smaller particles of lighter green blues with higher coloring power. Its a very practical pigment in glazes and mixed with white. Density: 2.34. Oil absorption rate ~ 35%.

Blue ultramarine very clear

Light ultramarine blue

Blue ultramarine greenish clear

Blue Lumière spinel

Dark ultramarine blue Greenish ultramarine extra

Blue Zircon spinel

Artificial ultramarine Blues

Colour Index Pigment Blue PB 29 77007 Chemical description: Aluminosilicate complex with an alkali metal sulfide. Synthetic variety of lapis-lazuli of Chemical Formula: Na2OSAl2O3SiO2 Non-toxic pigment. This blue was invented in the nineteenth to replace the too expensive Lapis-Lazuli. After a contest organized in 1824, by the company for the encouragement of national industry, with a price of 6,000 french francs, JB Guimet succeeded in manufacturing artifi-

Blue ultramarine, reddish Extra-dark ultramarine blue

Prussian blue also call berlin blue

Colour Index Pigment Blue PB 27 77510 et 27:1 77510:1 It is a pigment consisting of potassium (I), iron (II) and (III), sodium and water of chemical formula Fe7 (CN) 18 (H2O) n, where n varies from 14 to 18 and also Fe4 [Fe (CN) 6] 3 nH2O. It is prepared by precipitation of ferrous ferrocyanide, starting from an alkaline ferrocyanide and a ferrous salt, and then by oxidation in an acid medium when hot, using an al-


158

BLUE PIGMENTS

kaline chlorate. The fortuitous discovery of Prussian blue is attributed to Diesbasch and Dippel, between 1704-1707.It has good lightfastness, is resistant to acids and common solvents, but is decomposed by alkaline solutions, giving off brown ferric hydroxide. Mixed with titanium white, it allows to obtain a range of different and varied tones.It is advantageously replaced by the heliogene blue. Charron blue is a very charged Prussian blue variety. Density: 1.97 and Oil absorption rate 35%.Refractive index: 1.56 Light cobalt blue PB 35.77368

Prussian blue

Medium cobalt blue PB 28.77346

Greenish cobalt blue PB 36.77343

The Cobalt Blues

Colour Index Pigment Blue PB 28 77346 Pigment Blue PB 35 77368 Pigment Blue PB 36 77343 Pigment Blue PB 74 77366 Chemical Formula: CoAl2O4, Cobalt Aluminum with spinel structure for PB 28 Chemical Formula: CoO.SnO2 for PB 35 Chemical Formula: Co-Cr-Al Green cobalt chromite spinel for PB 36 obtained by calcination at 2400 ° C of a mixture of cobalt (II) oxide of chromium (III) oxide and oxide of aluminum (III) in various proportions. Chemical Formula: (Co, Zn) 2SiO4 for the PB 74 Density: 3.6 to 3.8 Oil absorption : 20 to 30% depending on the variety. Refractive index : approx. 1.70 There are a multitude of artificial pigments of cobalt, and according to their chemical compositions, of various colors. The cobalt blues consist generally by a mixture of double oxides of cobalt and aluminum, obtained by calcination of the metal up to its melting point between 1200 and 1300 °C. They have been known since 1804. These pigments are very stable to light, compatible with all techniques and with all pigments. sells 8 varieties of cobalt blue ranging from light blue, medium, dark, to sapporo, greenish, ceruleum, light and dark turquoise. The cobalt pigments are rather transparent in the oil. They are magnificent pigments in enluminure.

Cobalt Blue Sapporo PB 74.77346

Dark cobalt blue PB 74.77366

PB 35.77368 Cobalt blue ceruleum

Dark turquoise cobalt blue PB 36.77343

Cobalt Blue Turquoise PB 28 77346


159

BLUE PIGMENTS The Blue Ploss

It is neutral verdigris made up of copper and calcium acetate, also known as "crystallized" verdigris or "distilled" verdigris, but also " Purified "verdigris. Chemical formula : CuCH3COO.H2O and also : CuCa CH3COO2.2H2O. Pigment very bright, but not very stable in acid environment. It is more lively than the verdigris, but of a more acid tint, its like Prussian blue mixed with a lot of white. It is a siccative pigment in oil painting and it allows to realize the Spanish oil. H. Ploss describes the production of this pigment in his book, "A Book about Old Colors," with a reference to a book on colors dating back to 1500 from Trèves in Germany. The name of this pigment was chosen in his honor.

I have had great difficulty taking it in photo as its color is particular, see pigment collection, the big pot at bottom right on the left picture, (otherwise on the DVD to blue manganese).

Manganese Blue

Cerulean blue

Blue Ploss

Manganese blue

Colour Index Pigment Blue PB 33 77112 Pigment made up of 2 elements of MnO4Ba barium manganate and SO4Ba barium sulfate.It is prepared by calcining manganese chloride and barium dioxide at 700 to 800 °C. It has a high density which allows to recognize it easily. Pigment toxic because of the barium it contains and harmful because of the manganese. Refractive index: 1.65 and oil absorption: 30% It is a very strong pigment, which has been used since 1930. It is resistant to acids and alkalis, and is very stable to light.Compatible with all techniques, including fresco; It can be mixed with all pigments. Its rheological properties are poor, the pastes are difficult to handle. Grinded with water, it amalgamates very badly and it flour, it is better to use it in oil with addition of a little pure silica. Manganese blue is difficult to find as a powdered pigment. This blue looks like cyan in RGB.

Colour Index Pigment Blue PB 35 77368 Of Chemical Formula: SnO CoO Constituted by cobalt stannate (tin + cobalt), calcium sulphate is often added to it to regulate its viscosity, otherwise lumps will form and it would be very Difficult to agglutinate in binders when grinding on marble. It is prepared by calcining a mixture of cobalt sulphate, tin chloride and lime, the mass is then ground, washed and dried. Non-toxic pigment. Known since about 1860 (Rowney & Co). In a blue tone with light greenish reflections, this pigment is very beautiful in oil, in which it develops all its subtlety. It is one of the rare blues to cover in oil. It is a very dry pigment, thanks to the cobalt it contains. Mixed with yellow of Naples, it gives very beautiful green. It is difficult to find in the form of pigment powder. Average density ~ 3.8. It is compatible with all pigments and binders. oil absorption : 20 to 25%. Refractive index: 1.84


160

BLUE PIGMENTS Blue ash, lime blue, verditer blue, bremen blue and synthetic azurite

Colour Index PB 30 77420. It is a basic Copper (II) Carbonate of Chemical Formula 2CuCO3 · Cu(OH)2. Mixture of copper hydroxide Cu(OH)2 naturally present in several minerals such as azurite which is mixed with CaCO3 calcium carbonate. In fact, its artificial azurite (Scott.2002), which is called differently according to the filler used, lime blue, lime, gypsum blue, eggshell blue, and according to the nature of the lime , Extinct or not. They are pigments with an intense blue tone more greenish than the natural azurite that was used in the Middle Ages as a pigment in enluminure. It was used from the 17th to the 19th century as a decoration pigment often mixed with smalt to produce darker tones. In the 19th and early 20th centuries, it was used for the coloring of wallpaper. It is compatible with watercolor and tempera but not in oil because its low refractive index ~ 1.73 to 1.838. The particles of this blue are more rounded and more regular than the natural crushed azurite. The lime blue reacts with strong oxidants. Density 4.0 Kg / l. Thermal stability <200 °C. Lime blue carbonate basic copper

synthetic Azurite called Blue ash or blue verditer

There is also a lime green referenced to C.I Pigment Green PG 22 77412, an arsenite of copper precipitated Cu3 (AsO3)2 with calcium sulfate CaSO4. All these pigments are toxic.

Cavansite

hydrated calcium of silicated vanadium Chemical Formula: Ca (VO) Si4O10 (H2O)4 It is a vanadium and calcium silicate. Cavansite is a sky blue mineral crystallized in small needles. It is most commonly found in Poona, India, a city of the Republic of India in the state of

Maharashtra, located on a tributary of the Krishna River, northwest of the Dekkan on the Maharashtra lava plateau. 190 kilometers from Bombay. It is not known if it was used in Europe, but this light blue sky pigment, could be used in some mogul miniatures. Cavansite is a rare and very beautiful mineral. It was discovered in 1967 in Oregon in the USA and is only found in some localities in India. The best crystals come from the famous zeolite quarries of Poona, India. These crystal aggregates consist of spherical rosettes with prominent pointed crystals. The rarity and beauty of the Cavansite explain its recent popularity. It is preferable to use it in aqueous techniques. Very good resistance to Cavansite from light.

Pentagonite

It is a mineral species of the group of silicates and of the subgroup of phyllosilicates of Chemical formula Ca (V4 + O) Si4O10,4H2O. The chemical components Ca: V: Si of pentagonite are the same as those of Cavansite as well as H2O, because their unit cells have the same volume. Associated with Cavansite, calcite, analcime, heulandite, apophyllite and stilbite. It is found in the USA, about three kilometers south of Owyhee Dam, Malheur County, Oregon and Goa, India. It is of opaque turquoise color, very light-resistant and compatible with aqueous techniques such as Acrylic, Tempera, Enluminure, etc. ... Pentagonite from Goa , < 40 μm

The Aerinite

The Aerinite was discovered in 1876 by the German mineralogist A. von Lassaulx while studying a sample from the province of Huesca (Aragon, Spain). He baptized it "aerinite" (from the Greek: aérinos) in reference to its sky blue tint. Aerinite is an aluminum silicate and of hydrated calcium (ophic alteration of Triassic zones). Its deposits are located in areas near the Spanish Pyrenees (Porta et al., 1990) in Aragon, in the province of Huesca (Estropiñan del Castillo, Caserras, Juseu, Nacha), Catalonia, in the province of Lérida , Villa Nueva d'Avellanes, Ager, Artesa de


161

BLUE PIGMENTS Segre, Hostalets de Tosts), in Navarre, Andalusia, in the province of Málaga (in Antequera). The complex chemical formula proposed in the RRUFF ID R050610 database is the following (Ca,Na)6(Fe3+,Fe2+,Mg,Al)4(Al,Mg)6[Si12O3 6(OH)12](CO3)•12H2O and also (Ca5.1Na0.5) (Fe3+,Al,Fe2+,Mg)(Al,Mg)6[HSi12O36(OH)12] [(CO3)1.2(H2O)12]. In France, for the moment, only one deposit has been discovered in Saint-Pandelon, near Dax, in the Landes department [52]. Moreover, they are also found outside the Pyrenees, where other deposits have been discovered in Morocco, the Middle Atlas and the Anti-Atlas, on the outskirts of the city of Ouarzazate, in the north of Italy , In Portugal (in Serra d'Argo), in the United States (Arizona). The pigment is heated between 400 ° C and 600 °C to give it a greener tint, so the pigment loses its water of crystallization to acquire a greener green pale tone. This light green and rare blue pigment is available from time to time at . It is compatible only with aqueous techniques because of its low index of refraction, it will be transparent in oil. It is resistant to chemicals, heat and light.

nal coloring depending the origin of the origin of the mineral and the means of purification applyed. It is found in sedimentary deposits of minerals, in clay, in moors, deposits of brown coals and as inclusions in the fossilized bones and teeth, it is then called "Odontolite", also called turquoise of the bone or turquoise of fossil, a fossil or ivory bone, which owes its color to turquoise or phosphate minerals. The Vivianite may have a crystalline structure in the form of shimmering plates, but it presents itself more generally as an earthy deposit. Vivianite deposits are found in Cornwall, England, where it was discovered in Wheal Kind, St Agnes, and was named after its discoverer by John Henry Vivian (1785-1855), Serbia, and Germany. It Is also found in Krim in Ukraine, Bolivia, Colorado in the USA, Australia in Queensland, Brazil, Mexico in Chihuahua and in the elephant cemeteries of Cameroon. The Vivianite was rarely used in European easel paintings, but it was used to represent skies by the Cologne school in the thirteenth and fourteenth centuries. Ferrous phosphate was used as a pigment and was also called "blue ocher" by the Cologne School of the 13th and 14th centuries. The earthy form of the pigment was also identified in Dutch paintings of the seventeenth century, including the famous painting by Johannes Vermeer, "L'entremetteuse" (1656). The number of occurrences of Vivianite in paintings has steadily increased in recent years. It can be used in the pastel technique and with water-based binders; In oil, reflecting its refractive index of about 1,580, it will be transparent.

Aerinite. Iron magnesium silicate calcium and aluminum Estopinian Huesca Province Spain via Wikipedia

Aerinite 80μm

The Vivianite or Blue Ochre

Chemical composition : Fe3 (PO4) 2.8H8O Chemical structure : Fe3 2+(PO4) 2• 8H2O Chemical description : It is an hydrated iron phosphate. The Vivianite is a natural earth very bluish gray very rare therefore very expensive (1200 € / kg), it is a powder of blue pigment gray, which gives a shade violet or blue gray in the paintings with water, the fi-

Vivianite by Attila Gazo from Master pigments [2]


162

BLUE PIGMENTS

The Chrysocolla

Colour Index Pigment Blue PB 31 77437, like the Egyptian blue. Its name comes from the Greek "chrysos": gold and "kolla" glue, which refers to the name of a material to weld gold. The chrysocolla is an old term designating various materials used for the preparation of gold, but which is refined over time and today refers to a mineral, hydroxylated hydrated copper silicate of general chemical formula : (Cu, Al)2(H2Si2O5)(OH)4• nH2O The chrysocolla has been used as a semi-precious ornament for at least 3000 years BC. It is a mineral usually found in secondary copper mines. The chrysocolla is often associated with azurite and malachite in the same mine as well as with tenorite, halloysite, nontronite and allophane. In some copper-bearing Arizona mineralities, it has been found with the chrysocolla in 92 other deposits around the world where the two minerals are found together. It is also found in the Timma mine (King Solomon mine) in Israel, Russia, Congo, Australia, Slovakia, Chile and Mexico. In its natural state, it may resemble malachite, however its tint is more bluish, turquoise, it looks very much like turquoise. Because copper is bonded to a silicate matrix, it is a pigment that is poorly soluble in acidic media, which is why it can be used in oil, but it will lose its beautiful color in It. It is preferable to use it in aqueous techniques or as "Titian", to sprinkle it on a bed of binder (in our time a binder type Plexisol © or another clear binder solvent phase fast hardening. Excellent resistance to light, but is decomposed by powerful acids, alkalis, and heat.

Very beautiful Chrysocolle my mineralogist brought me back from a trip to australia.

It is a pigment which develops such a beautiful shade in the technique of enluminure, bound with a binder such as egg white, the most transparent of all vehicles, the color of the pigment is so preserved. Hardness (Mohs) ~ 2 to 4 Density ~ 2.0 to 2.8 Kg /l Refractive index ~ 1.575 to 1.598

Natural Chrysocolla

Copper Blue - Very light turquoise blue

It is a copper phosphate of chemical formula Cu5 (PO4) 2 OH consisting of ~ 32.4% phosphorus pentoxide P2O5 and ~ 59.2% copper oxide CuO, also found in nature such as libethenite, A rare mineral of copper phosphate hydroxide. The tonality of this pigment is very difficult to obtain by mixing. Like azurite and malachite, all pigments containing copper are unstable and can degrade and turn blackish over time in oil painting. This pigment exists in various shades according to the way of making it and the proportion of its components. It is compatible with all aqueous techniques, including lime and fresco in which it is more stable.

Copper Blue


163

WHITE PIGMENTS

Zirconium White

Barytine White

Titanium white XSL

Barytine White

Titanium white

Zirconium White

White silver

Tin White

Natural titanium dioxide

Tin White

Lithopone

White lead

Solid white

Titanium white

Zinc white

Zirconium White

Ilmenite

St. John's White

Bismuth White

Titanium white


164

WHITE PIGMENTS The Lead White called Ceruse

Says also Silver White, Cremnitz White, Berlin White, Holland White, Clichy White, Krems White, Vienna White, Lead Flakes or Flakes white, etc. ... Color index: Pigment White PW 1 77597 It is a basic carbonate of hydrogenated lead. Chemical Formula: 2PbCO3 Pb (OH)² And also C2H2O 8Pb3 or 4PbCO3 • 2Pb (OH) 2. Natural and artificial mineral pigment Refractive index: 2.1 Oil absorption rate : ~ 10 to 15% according to samples Thermal decomposition: approximately: 315 ° C Density : 6,9 Kg / l at 20 ° C Insoluble in water at 20 ° C pH : 7 per 100 g / l water, at 20 ° C Soluble in acids and alkaline solutions It is known since Antiquity (Pliny the Elder). The lead carbonate is naturally present in the cerusite, which may contain traces of Sr, Zn, Cu, crystallizing in the crystal system, one of the three lead ores found sufficiently abundantly to form exploitable deposits in order to constitute lead in solid state. It is possible to make this white by putting thin plates of lead, suspended in a closed container and waterproof, at moderate heat, in the presence of vinegar and/or manure. A white, powdery layer forms on the surface of the metal, after a few weeks, this white powder is recovered by scraping, which is purified by successive washing in water. The higher the lead content of the metal, the more pure and white the pigment. " Cerusite Les Frages " BY Didier Descouens

Silver White

There are different methods of manufacture, but for a final pigment of good quality it should contain about 70% lead carbonate and 30% finely divided hydrated lead. This white is banned in France since 1916. If you are not professional, it is unlikely to be available, its use as so many other historical pigments is rightly regulated. If you often use toxic pigments, be sure to do a blood-oriented heavy metal analysis every once in a while, as lead will accumulate. I have been using this white for more than 25 years and I have never had a problem, from the moment when we apply certain safety rules, there is no reason to be inconvenienced, Moreover, used with Rubens medium technique, it is isolated, as in a gangue and therefore non-reactive, once hardened. In any case, the pigments are not made to be carried to the mouth. I read an article about sulfur in the form of hydrogen sulphide or hydrogen sulphide (H2S) released into the air that is detrimental to pigments, but the sulphide emissions are much less in our time (in 2016) Than any other, which consequently implies that our modern pigments have less to fear from the aggressions and injuries of the atmosphere than at any other times. In air, hydrogen sulphide H2S is oxidized by oxygen or hydroxide radicals, thus forming sulfur dioxide and then sulphates which can be removed from this compartWhite lead of 1900 ment by absorption by plants, Recovered in an old factory soil or precipitation . [125]. The white silver is the most beautiful of the whites for the oil and tempera paint, it is irreplaceable, moreover it requires only 13% of oil during the grinding. The films he produces are very hard (but elastic), at the limit of the break, which is why I always add a small dose of saponified wax mixed with "clear oil" in order to plastify it. It is a pigment which hardens very quickly, in a few days, depending on the applied thickness, it can already be glazed. Master Pigments® makes and sells white silver in "Flakes" of unsurpassed quality [2]. Think grinding in case it would contain impurities, your lead white on the marble first into water, and then stepwise add the oil, which will expel the aqueous liquid and thus complete purifying White lead of 1990 the pigment.


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WHITE PIGMENTS The Titanium White

Colour Index Pigment White PW 6 77891 Refractive index of the Rutile : 2.71 Anatase refractive index : 2.42 Oil absorption rate : 18 to 22% depending on the sample Density : 3.9 to 4.26 depending on the quality Chemical Formula : TiO2 There are 4 types of titanium dioxide pigment with a titanium content of 80 to 98% minimum with barium or calcium sulfate as filler. The pigment that interests us in artistic painting is the purest and it consists of titanium dioxide, derived from the black titanium ore of ilmenite, an iron and titanium mineral of Chemical Formula FeTiO3. The white was made by hydrolysis and calcination at 900 °C. of the ore to obtain titanium dioxide. The former sulphate process is performed as follows : dissolving the ore in sulfuric acid, purifying the aqueous solution of titanyl sulphate, precipitating it into a hydrated titanium oxide gel, and calcining the gel to be crystallized in aggregates of pigment particles, which are ground. At the present time, titanium whites which are produced are more environmentally friendly with a chloride process without dilute acids. Rutile is the most used, as it is more hiding than anatase, however the anatase variety is whiter. Rutile absorbs a little more violet light than anatase and is slightly more yellow, but does not interfere with the mass pigment. The rutile crystals are elongated, denser and have higher refractive indices. Due to their high refractive indexes, rutile pigments diffuse light more efficiently than those produced with anatase. They are also much less chalking. The rutile Ilmenite is lipophilic whereas the anatase is hydrophilic, it must be taken into account when making emulsions. The present TiO2 titanium pigments are complex structures composed of an optically active core with a coating which adapt the pigment for specific uses; Their optical performance approaches the diffusion efficiency of the theoretical light. The theory of diffusion consists in studying the collision between two or more particles. To check that the pigment is pure, the titanium white rutile although of slightly bluer tone than the white of lead, is rather a frank white.

Rutile titanium white is considered to be the most hiding of all whites, however to develop a maximum covering power its primary particle size should be between 0.02 and 0.3 μm. Typical composition of a titanium white Titanium 89% Silica 5,5 % Alumina 3,3%

White Titanium Rutile

The advantages of titanium white are high strength, opacity, good UV resistance and inexpensive. Its disadvantage is that it forms in the long run radicals which degrade the binder. No pigment is perfect !.


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WHITE PIGMENTS The Titanium White XSL

By special treatment by precipitation of the titanium oxide (at the core of the particles), by hydrolysis of the titanium alkoxide (an alkoxide is the conjugated base of an alcohol and therefore consists of a bound organic group to an oxygen atom negatively charged), this pigment can so be easily and rapidly mixed with the water in which the particles are perfectly dispersed.They are stable pigments in acids, bases and lime, they are also very resistant to light. Areas of application of XSL white : Oil, Acrylic, tempera, Water-based, Lime, Fresco, Cement, Lutherie, Ceramic, Silicate Binder, Painting on Glass.

7 others Special XSL pigments for aqueous binders They behave in water like dyes although they are inorganic, mixing them perfectly with her. XSL Translucent Yellow C.I. PY 42.77492 XSL Red Coquelicot C.I. PR 112.12370 XSL translucent red C.I. PR 101 77491 XSL Irgazine DPP red C.I. PR 254 56110 XSL royal blue Phthalo C.I. PB 15: 2.74160 XSL Yellowish green Phthalo C.I. PG 7.74260 XSL Smoke Black C.I. PBk 7.77266 http://bit.ly/Pigments-XSL

Titanium dioxide Natural chamois

Colour Index Pigment White PW 6.1 77891 Chemical Formula: TiO2. It is the second most used titanium ore. The pigment is produced by grinding the chamois rutile ore which contains about 95% titanium dioxide with small amounts of iron and other impurities. In industry it is used when titanium is capital, but the final hue does not have to be necessarily white. It has a very beautiful shade of jarosite, but more light yellow. It can be used in all techniques and with all binders. Resistance to light 8 is perfect. Oil absorption ~ 25%.

XSL White titanium

XSL White titanium

Natural Titanium chamois

The Zinc White

XSL pigments from . Description above

Colour Index Pigment White PW 4 77947 Chemical Formula : ZnO Composed of zinc oxide ZnO at 99.8% min, and traces of other minerals such as copper 1 mg/kg max, manganese 1 mg/kg, iron (Fe)2 mg/kg max, Lead (Pb) 15 mg/kg max, cadmium 10 mg/kg max, arsenic 5 mg / kg .Density = 5.5 to 5.7 Refractive index: 2.01 Oil absorption ~ 20%


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WHITE PIGMENTS The natural ores of zinc consist of blende, sphalerite (ZnS) and calamine (CO3 Zn). The metal is obtained by roasting and direct reduction by carbon, with air injection at the time of the reduction of the metal. Zinc was known as early as the 1st century by Dioscorides (physician and botanist) and alchemists of the Middle Ages who called it "Lana Philosophica", but it was not known or used in painting. It was around 1780 that it appeared, but was not really used by painters until about 1850. It was marketed in the nineteenth century at the end of the fight between white lead and zinc white to reduce cases of lead poisoning, the workers who were preparing the white lead and painters for building that used it, however, despite all the advertising around the zinc white, it was titanium white that took advantage of it and that lives Its production and its demand tenfold. This white has some defects, and not the least, it has a tendency to crack with oil and is unstable in an acid environment, on the other hand it is not toxic. It is used in industry for anti-corrosion coatings. It is best to use it with aqueous paints and techniques like gouache.

It is no Toxic. It is better to use quality lithopone, so it will be compatible with all binders and pigments.It has good coloring and hiding power. Its performance over time is verified, if it is of good quality.It is generally used in glazed paints, due to its good resistance to acids, in coatings with hide glue, up to 20 to 30% maximum, in order to make them whiter.

Lithopone

The Solid White or Barytine White

zinc white

The White of Lithopone

Colour Index Pigment White PW 5 77115 Chemical formula : BaSO4 + ZnS ZnSO4 + BaS --> BaSO4(s) + ZnS(s) Density : 4,3 Refractive index : 1.84. oil absorption : 20%. Consisting of zinc oxide and barium sulphate. Coprecipitation of zinc sulphide and barium sulphate in proportions of about 60% zinc sulphide and 40% barium sulphate.Calcination of the result of the two mixtures at about 1000 ° C, protected from air, washed and then reduced to powder. Created and patented by G.F. Douhet, the november 6, 1847.

Colour Index Pigment White PW 21 77120 artificial and PW 22.77120 natural. Chemical formula: Ba(SO4), consisting of natural or synthetic barium sulfate (purer chemically, it is brighter than Barytine), in powder, of high purity, obtained by precipitation. It has a low hiding power. It is one of the most stable pigments and is therefore used to increase the density of expensive pigments or to agglutinate an excessively dense titanium white. It is the most stable filler with oil to make coatings or reparure, to avoid using chalk that is too unstable with acidity. Refractive index ~ 1.55. Oil absorption~ 20%.


168

WHITE PIGMENTS The Tin White

Colour Index Pigment White PW 15 77861 Tin dioxide of Chemical Formula: SnO2 The tin is extracted from the cassiterite, which is its principal mineral. Prepared by heating the metal in air, we obtain, a white powder that was used in the Middle Ages, in enamels. It is a hiding pigment. It was proposed to be used in painting, but its manufacture is too expensive, compared to other white (about 90 € per kilogram). Used to give nacreous effects to paints and pigments, used in ceramic glazes and also as polishing agent for glass and metal. Possible techniques: acrylic, tempera, water-based paint, ceramic, silicate binder, paint on glass.

static coatings, anti-reflective coatings in solar cells, in the manufacture of gas sensors, in optoelectronic devices and resistors as well as in the manufacture of liquid crystal displays and touch screens of tin-indium oxide. In powder form, white tin ashes are currently (2019) commercially available.

Tin White

Very nice Cassiterite with muscovite By Carles Millan Size 100 mm x 95 mm Weight 1128 g

In painting, tin oxide ashes are used to give subtle pearlescent effects to pigments. Tin white is also used in ceramic glazes and as a polishing agent for glass and metal. Tin white can be used to temper a pigment that is too strong and to give it reflective characteristics, but also to increase its refractive index in order to make it more covering.

Tin oxide SnO dissolves in strong bases to give stannates, with the nominal formula Na2SnO3. Dissolving the melt of solidified SnO2 / NaOH in water gives Na2 [Sn (OH) 6] 2 "a preparatory salt" used in the dye industry. Tin oxides dissolve in acids to give hexahalostannates, so care should be taken to use with tin white, binders that are neither too acidic <2, nor too alkaline> 13. Quadrivalent SnO (IV) tin oxide is one of the most studied metal oxides in our time, due to its many applications and its potential. It is also a good bactericide, a fungicide, a myxobactericide (microbial control agent), a stabilizer in plastics and it is also used, but more rarely, as gilding with tin foil. Tin oxide nanoparticles are used because they form barriers that allow after oxidation and / or reduction to manufacture all kinds of high performance material, such as magnetic data storage, magnetic resonance imaging, as catalysts, as energy-saving coatings, antiTin White


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WHITE PIGMENTS Pure, it is a beautiful pigment, very luminous and very masking, with a high refractive index of 2.006 (a little less than titanium white). It was proposed for use in painting in the 20th century, but its manufacture is very expensive, compared to other whites, it costs around € 90 per kg, the most beautiful white to water and the cheapest is cristobalite! Compatible techniques: Acrylic, tempera, gouache, cera colla, ceramic, silicate binder, polyurethane, etc. Instead, use it in polar, aqueous techniques, making sure to check the pH of the binders. In view of the properties of the mineral, the pigment is very resistant when used under good conditions.

Bismuth nitrate is used for base patina and is also a rust inhibitor on aluminum, steel and iron. When mixed with water, it will create a white base, to which can be added varying levels of oxides and carbonates to obtain deeper patins. Techniques: Acrylic, Tempera, Ceramics.

bismuth Nitrate

Le Bismuth nitrate

Colour Index Pigment White PW 17 77169 Also named, basic bismuth nitrate, white of paint, paint white, cosmetic white, bismuth Magistery, Snowcal 55W, Vicalin, Vikaline. From the Greek "psidymos", silver white, from the Arabic "bi ismid": having the properties of antimony. Bismuth was identified in 1753 by Claude Geoffroy le Jeune, but it was already mentioned as metal by Agricola, a 15th-century mineralogist who latinized the name in bisemutum. Paracelsus, a German physician (1526), knew him under the name of wismat. Chemical formula : Bi5H9N4O22 Consisting of> 98% bismuth subnitrate.It is obtained from its ore (the bismite) Density : 4.93 - (water = 1)

Zirconium White also called Zirconia White

Colour Index Pigment White PW 12 77990 for the Zirconium Oxide CAS No. 14940-68-2 The zirconium white consists of zirconium oxide (ZrO 2) a white zirconium anhydride. It is composed of monoclinic zirconium dioxide having a zirconium oxide content (including hafnium oxide) between 94.5% and 99.40%. Chemical Formula ZrSiO2 It is an inorganic pigment, mineral, of the twentieth century, it was formulated recently, Blumenthal & Jacobs in 1973, and Broochwicz in 1993, indicated two ways of making this white zirconium analogous to the minerals of arkelite and baddeleyite. 1. Zircon and carbon are baked at more than 2000 °C. to form zirconium carbide (ZrC), the precipitate is burned in air to give zirconium oxide. 2. Zirconium salts are precipitated by alkaline sulphate, giving a very pure form of polysulphate-polyzirconium acid which is calcined in order to make the pure oxide.

Bismite

It has an appearance of white crystalline powder, insoluble in water. Odourless. Soluble in acids. It has an affinity for water. It is commonly used as an astringent and antiseptic. Trivalent Bismuth (III) nitrate Bi(NO3)3·5H2O is a highly soluble crystalline bismuth source for compatible uses with nitrates and low pH acids. Nitrates are also oxidizing agents.

The pigment is in the form of a white powder and constitutes a number of compounds used in the manufacture of paints and dry additives, coating pigments, various catalysts, paper primers, ceramics pigment manufacture, welding fluxes and insulating materials in the production of piezoelectric crystals, high frequency induction coils, glazes for ceramics, glass, heat resistant fibers. Zirconium is also used for the coating of titanium pigment (TiO2) and leather tanning. The zircon is an effective opacifier because of its high refractive index. The finely ground zircon crystals are capable of dis-


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WHITE PIGMENTS

persing all wavelengths of visible light thus making the ceramic more opaque and white. It is an effective opacifier which has a refractive index which differs greatly from the medium in which it is in suspension.

zirconium white

Approximate composition of zirconium white ZrO2 > 63,5% TiO2

<0,20 %

Fe2O3

<0,15 %

Al2O3

<1,5 %

SiO2

<33 %

Uranium

230 to 280 ppm

Thorium

170 to 230 ppm

The zircon has the additional advantage of high hardness (7.5 on the Mohs scale) making it a scratch and a mechanical resistant product. This white zirconium pigment is not considered hazardous according to EC Directive 67/548 / EW. Its melting point is 2200 ° C. Loss on fire <0.9% It is insoluble in water. It is a non-flammable pigment. Density between 4.6 and 4.8

For a typical ZrO2 sample, the refractive index of the zirconium white is 2.40 Oil absorption rate of 16 to 20% Compatible with all techniques and all binders. I have been looking for a white pigment that could replace the white lead, toxic, I tried this white of zirconium, pure and mixed with other white pigments in oil, to constitute a white covering, frank , I must say that it is very promising, moreover it has a refractive index of 2.40, which is not negligible. sells this white under the denomination "White of ". The photos do not pay homage to him, because he is really an immaculate white. Zirconium compounds are also used in solvent-based paints as a coordinating siccative where zirconium carboxylate can be used in place of toxic siccatives with lead and as a thixotropic agent in water-based paints. Ammonium zirconium carbonate is used with a variety of resins to improve the resistance of paints to heat and friction. Zirconium fluoride is used in the treatment of metals to improve the adhesion of metallic aluminum paints. Titanium acetylacetonate was a widely used standard adhesion promoter, but zirconium propionate replaced it as a flexographic adhesion promoter and for gravure inks to improve adhesion on reticent substrates. Zirconium chemicals are used for applications that include paper coatings, paint siccatives, antiperspirants, printing inks, paints and catalysts.

Tungsten White

Hydrated barium tungstate. Colour Index Pigment white PW 13 77128 Chemical formula : WO4BAH2O It consists of a mixture of solutions of tungstate of soda and of barium acetate.It is a little used pigment, but used in painting of art.In view of the price of its very expensive manufacture, unfortunately industry abandoned the manufacture of this pigment, which nevertheless possesses good hiding qualities and which is unalterable, it deserves to be noted.

Tungsten Metal


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YELLOW PIGMENTS

Nickel titanium yellow

Nickel titanium yellow greenish

Baryum yellow

Zinc yellow

Praseodymium yellow

Jaune de Chrome

Priderite yellow

Lead Tin yellow

Cobalt yellow

Orpiment

Orpiment

Priderite yellow

Bismuth yellow bright

strontiane yellow

Orpiment

Nickel titanium yellow

Bismuth yellow

strontiane yellow

dark naples yellow

Bismuth yellow


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YELLOW PIGMENTS

The Orpiment

Colour Index Pigment Yellow PY 39 77085 and PY 39 77086 for the synthetic variety. Royal yellow, imperial yellow, orpin. The name is derived from the Latin word aurum : gold and pigmentum : dye "auripigmentum or auripigmento" literally meaning "gold pigment" or "golden color" that made him take to gold by the Romans. Refractive index : 2.9 to 3.1 depending on the sample Oil absorption between 60 and 70% Orpiment is a natural mineral of the sulphide class, it is a yellow arsenic trisulphide of the formula : As2S3 or As2S5, sometimes containing impurities or traces of mercury, germanium, and antimony. The synthetic variety is much more toxic than the natural mineral in its pulverulent form. Its use nowadays is highly regulated as lead white.

It is an anti-drying pigment, sometimes it takes up to 3 months for a thin layer of oil paint to harden. It is one of the longest pigments to be grinded under the wheel, it has a rubber-like texture, despite a homogeneous structure. The orpiment can not withstand the lead or copper with which it decomposes rapidly, I have not observed this phenomenon in my paintings. Mixed with indigo, it gives very beautiful green. In its natural mineral form, the orpiment is very stable to light if it is ground with drying oil and the medium of Rubens is added to the dough. It is dissociated only by strong acids. I painted in 1993, a painting on Orpiment wood, the orpiment did not move. (See paint below). It is worth to be used, because its nuances are really subtle, moreover, it is of remarkable intensity. It is used with skin glue, oil, or in the techniques of enluminure with egg white and gummed water. It can not be used, in the technique of fresco.

Realgar Vein I am not talking about Réalgar in this book because it is a poison. Raw Orpiment ©2016 Damour David

Its toxic properties were used to repel insects. Orpiment usually occurs in association with the red realgar (the more it contains The more it is orange), in vein with silver and lead ores, but also in the form of nodules in beds of sandy clay. It comes from Bohemia, Transylvania, Romania, Iran, Georgia, Utah, Kurdistan, Peru, China and Macedonia in Greece, as well as near volcanoes such as Mount Vesuvius and Mount Etna. It is often associated with stibine, pyrite, realgar, calcite and gypsum and sometimes with native sulfur. It is also used as an arsenic ore, containing up to 61%. Moreover, when it is grinded on the marble, he has a strong smell of sulfur. Formerly, it was also used in the dyeing and printing of calico and by tanners to remove the hairs from the skins. Its shades range from bright yellow to orange depending on whether it contains more or less realgar and also according to the fineness of the grinding.

The nave of this Salisbury church and the floor of this oil painting on wood are painted with orpiment, and unpurified azurite in the center. 60 X 60 cm. © 1993-2016 Damour David


173

YELLOW PIGMENTS Yellow of Naples

Colour Index Pigment Yellow PY 41 77588 et 77589 It is an artificial mineral pigment, a lead antimonate of the Chemical Formula : Pb2Sb2O7, for lemon and dark and for reddish yellow Pb3(SbO4)2. It consists mainly of a mixture of oxides of antimony and lead, the nuances of which may vary from lemon yellow to orange yellow, depending on the proportions of the two materials. For information there is a mineral, Bindheimite of Formula Pb2Sb2O(O, OH) named after a German chemist J.J. Bindheim, but also Rosiaite a very rare mineral of formula PbSb2O6, discovered around 1996 in Cetine mine, Italy. These two minerals have never been used as pigments, certainly because they are too rare. The yellow of Naples is made by calcination of a mixture of lead monoxide, antimony and sulfur or alkaline tartrate. Toxicity of Lead Compounds. Oil absorption rate: 15 to 25% depending on the variety. Refractive index of 2.2 to 2.8 depending on the samples. The history of the yellow of Naples is rather obscure. The compounds of lead and antimony are known to have been used in Babylon and Assyria for the production of glazes for yellow ceramics, approximately in the fifteenth century. AD, it was one of the few opaque yellow pigments in ancient Egypt and Mesopotamia, used as glass and glazes for ceramics. Its use in Europe dates from the fourteenth century. The first recipes of this pigment are those of Cipriano Piccolpasso who gives 7 variations for his production, in his book "Li tre libri dell'arte del Vasaio" written between 1556 and 1559. Its name comes from an expression of Andrea Pozzo "Luteolum Napolitanum ", which is referred to in one of his treatises published in Rome between 1693 and 1700. It was widely used in Europe from 1740 to about 1850. At present, you can find of good quality from . The pigment is homogeneous and divided gently, it has good covering power and very good lightfastness. The yellow of Naples does not have a crystalline structure and resembles the massicot (yellow lead oxide). Chemically it is fairly stable. However, because of the presence of lead, it can darken under the action of atmospheric sulfurous hydrogen, although nowadays this problem is less. It can gray on contact with iron, tin or zinc, I have personally found this fact. It is advisable to use a plastic or wooden knife to mix the paint or the pigment. It will be more judicious to use it, grinded in oil and enclosed in a medium like the "Rubens medium" type, rather than in an aqueous binder. Naples yellow is compatible with all pigments and binders. It requires little oil, 15 to 35% depending on the samples, and it is very siccative in oleaginous and oleoresinous binders.

Dark Naples Yellow

Bindheimite By Rob Lavinsky iRocks.com via Wikimedia

Naples yellow lemon

Reddish naples yellow

Naples yellow

Lead Tin Yellow or Verriers Yellow

Colour Index Pigment Yellow PY 77 629 Chemical formula : Pb (SbSn) O3 et Pb (Sn, Si) O3, Light tin lead Yellow Type I= Pb2SnO4 is a lead stannate prepared from a heated mixture of lead dioxide with tin dioxide. Type II is a lead silicate and tin oxide produced by melting lead, tin, and quartz at about 800 °C. Toxic pigment. oil absorption about 15 to 25% Refractive index about 2.0 This pigment is very hiding and slightly drying in oil. Its use in easel painting was between 1500 and 1750, as it was gradually replaced by the yellow of Naples. It was discovered by Jacobi in 1941, on works. It is the beautiful yellow used by Vermeer, but also by Rembrandt. It can be found from 's shop under three distinct varieties. Kühn (1968), distinguished in his time, 2 types of lead tin yellow.


174

YELLOW PIGMENTS Dark lead tin yellow

lead tin yellow light

lead tin yellow type II

Bismuth Yellow also known as Vanadium Yellow and Bristol Yellows (mixtures) Colour Index Pigment Yellow PY 184 771740 Chemical composition : 4BiVO4•3Bi2MoO6 It was introduced on the market in 1985. It is made by dissolving bismuth nitrate, sodium vanadate and sodium molybdate in nitric acid followed by precipitation of a complex mixture of metals. The precipitate is calcined to give a polycrystalline product.

It is recommended for use with alkyds and acrylics, water-based paints, nitrocellulose lacquers, and cooking enamels. The pigment has excellent weathering resistance, good coverage, gloss, and excellent lightfastness. Its thermal stability is also good. It is bright and luminous, making it a good substitute for toxic yellow pigments. It is an opaque pigment, bright yellow, proposed to replace the yellow of Naples. There are 4 shades : lemon, light, medium and dark. Bismuth yellow has a much higher saturation than yellow pigments of iron oxide and titanium nickel. It advantageously replaces cadmium yellows. It is compatible with all binders and pigments. Very low toxicity [71] Density: 6,7. Refractive index of 1.9 to 2.4, depending on the variety. Oil absorption 25%. Bristol yellows are a mixture of vanadium, they can replace zinc yellow. In spite of their ionic character, they are very resistant in alkaline and acidic medium, they have excellent thermal resistance and excellent resistance to light.

Yellow bismuth dark

Yellow bismuth average

Bismuth yellow light

Yellow bismuth lemon

Cobalt Yellow or Aureoline

Colour Index : Pigment Yellow PY 40 77357 Chemical composition = [Co (NO2) 6]K3 + 3H2O It is an artificial mineral pigment, a mixture of cobalt salts and potassium nitrate. It exists since 1848, but it is only used in painting since 1861. refractive index of 1.70 to 1.75 depending on the samples and oil absorption: 20% Toxicity of cobalt salts. It is light stable, but is not resistant to acids and alkalis, therefore it is preferable to use it in aqueous techniques.


YELLOW PIGMENTS

175

also saw the invention of new pigments increasingly stable, such as bismuths, praseodyms zircon and spinels. Cadmium pigments are often charged with BaSO4 barium sulfate even when the pigment has been sold as pure.[21] Cadmium Yellow N°1 lemon

Yellow of Cadmium N°2 very light

Cadmium Yellows

Cobalt Yellow

The Color Index distinguishes in the case of pure cadmium yellows PY 37 77199 and PY 35 77205 from Zinc Sulfide Cadmium and then PY35 :1 77205 :1 and PY37 : 177199 :1 from the varieties charged up to 60% with barium called cadmium lithopone (a mixture of CdS with barium sulfate BaSO4). These are cadmium sulfides for PY 37 and cadmium and zinc sulphides for PY 35.Chemical Formula: CdS and CdS + ZnS oil absorption : 20% Refractive index : 2.5 There are 6 cadmium yellows from lemon to orange. Soluble salts of toxic cadmium, not compatible with lead and copper. Discovered in 1816, by a German pharmacist, Stromeyer. Cadmium sulfide was used in painting from 1840. The pigments were prepared by precipitating an aqueous acid solution of a cadmium salt (chloride or sulphate), either by hydrogen sulphide or by a solution of alkaline sulphide for clear cadmiums ; dark cadmiums are made by mixing cadmium sulphide and zinc sulphide. They are compatible with all binders except fresco. Modern pigments with cadmium have a very good resistance to light. I use little of these pigments because they are incompatible with lead white, moreover I prefer the high performance pigments of spinel as well as the yellows of bismuth and Praseodymium/Zircon; Inevitably the cadmiums, given their prices and their toxicities, are doomed to disappear from the palette of the painter, out over a shorter or longer period, and

Set of cadmium Pigments from

Cadmium Yellow N°4 clear

Yellow of Cadmium Average N°6

Yellow of Cadmium N°9 dark

Yellow Praseodymium/Zirconia/Spinel/Rutile

Colour Index Pigment Yellow PY 159 77997 Oil absorption about 36%. Density = 6.78 - 6.81. Refractive index of 2 to 2.1 It consists of 52 to 61% of synthetic or natural zircon oxides, 22 to 33% of silica, 3 to 5.5% of praseodymium oxide, 0.2 to 1.8% of yttrium oxide and 6 to 10% mineral oil; Its composition may comprise a combination of alkaline modifiers or alkaline earth halides. Its Chemical Formula would be of the type: ZrO2 + SiO2 + Pr6O11 + Y2O3. Praseodymium is of importance, the 39th element constituting the earth's crust. It is a very recent pigment, a yellow pigment of zircon and praseodymium oxide.


176

YELLOW PIGMENTS

Praseodymium Yellow

Priderite Yellow

Titanium Nickel Yellow and Greenish Spinel Yellow

Other pigments are prepared with components such as spinel, corundum, rutile, zirconium silicate and the like.... Yellow praseodymium currently represents about half of the zircon-like colors produced in the world. This predominant position is mainly due to the fact that it is a very pure pigment. These pigments are very stable and very pleasant to use. These are the pigments of the future, indispensable on the palette of the 21st century painter. The yellow zircon/praseodymium is stable up to 1280°C. Melting point 930°C.

Pridérite Yellow said Primerose Yellow And also Daipyroxide Yellow

Colour Index Pigment Yellow PY 157 77900 The structure of the primerite is related to the structure of hollandite (a natural oxide of manganese and barite). Its chemical composition is complex, it is a mixture of oxide of Nickel (II), of oxide of Barium (II) and of oxide of titanium (IV) heated at high temperature. Chemical Formula close to BaNiTi7O16. It is generally synthesized from barium carbonate BaCO3, basic nickel carbonate NiCO3 and titanium dioxide TiO2, in a reaction at high temperature. One of the purposes of its synthesis is to minimize the level of acid-soluble barium. A difficulty in the complete realization is the decomposition of the BaCO3 while avoiding a high eutectic BaO / BaCO3 temperature (a mixture of two pure bodies which melts and solidifies at constant temperature). In addition, the reaction is complicated by intermediate BaxTiyOz species which form to varying degrees upon calcination. Oil absorption rate about: 22% to 27% Refractive index: 2 to 2.1. Average density.

Colour Index Pigment Yellow PY 53 77788 Consisting of a mixture of mixed oxides of antimony, nickel and titanium. Chemical Formula: (Ti, Ni, Sb) O2. It is produced by high-temperature calcination of oxides of antimony, nickel and titanium with CdO, Cr203 or Li2O modifiers. Density: 4 to 5 Kg / liter. Oil absorption: 14-18% depending on the variety. Refractive index of 2 to 2.1.Its stability limit is 950°C. It was developed in 1954 by the Harshaw Chemical Company to replace Barium Yellow. It is an opaque pigment, which has a low covering and dyeing power. Its toxicity is not demonstrated. There are two varieties, one of which has a beautiful slightly greenish yellow. They are both compatible with all pigments and binders. Perfect lightfastness.

Titanium Nickel Yellow

Greenish Titanium Nickel Yellow


177

YELLOW PIGMENTS Zinc Yellow

Colour Index Pigment Yellow PY 36 77955 et 36 : 1 77956. It is constituted by a mixture of complex chromate of zinc and potassium of schematic formula : 3 CrO4Zn, CrO4K2, ZNOH2, 2H2O. The zinc yellow is prepared by mixing solutions of zinc sulphate and alkaline dichromate. There are several chromates of zinc, depending on their precipitation, various shades are obtained, from lemon yellow to orange-yellow. The natural zinc ores consist of blende, sphalerite (ZnS) and calamine (CO3 Zn). The metal is obtained by roasting and then by direct reduction by carbon, by means of injection of air at the time of reduction of the metal. The zinc yellow has a poor resistance to acidic and alkaline agents, but excellent resistance to light.

Chrome Yellows

Colour Index : Pigment Yellow PY 34 77600/603 andPY34:1 77603:1 : Variety with lead sulphate. The word chrome comes from the Greek "chromos" which means "color".Chemical constitution: PbrCO4 + PbSO4 according to the lead content, more or less strong, the yellows are lemon to orange. These are pure lead chromates or lead sulpho chromates prepared by precipitation of nitrate, acetate or lead sulphate solutions with sodium bichromate solution, filtered and then washed, dried and ground.Various shades of bright lemon yellow to orange yellow are obtained depending on whether they contain basic chromates or other adjuvants such as sulfur. They are distinguished by numbers from 0 to 4, from orange to red (see orange). Pigment toxic, but the modern varieties of yellow chromium, coated (so called ultra) and highly stabilized, are weakly toxic, moreover they are less soluble in acids, and have good resistance to light, heat and atmospheric agents.

Zinc Yellow

Chrome Yellow

Zinc was known as early as the 1st century by Dioscorides (physician and botanist) and alchemists of the Middle Ages who called it "Lana Philosophica", but it was not known or used in painting; It was around 1780 that it appeared, but was not really used by painters until about 1850. In a too thick layer, with oil, the zinc has a tendency to crack, it is preferable to reserve it to the aqueous techniques. In fact, zinc yellow has a tendency to rehydrate if heat increases, which is why it is said to be unstable with oil paint. Nontoxic. It has anti-rust properties. Density: 3.4 to 3.46 and oil absorption: 20%. Refractive index of: 1.84 to 2.01.

Do not mix them with pigments such as ultramarine blue and lime, therefore, in fresco. These pigments were invented and developed by Louis Vauquelin in 1797, when he discovered the action of lead salts on chromium. Crocoite, a natural mineral discovered in 1766, in the Urals, was used only very confidentially, as a pigment. The industrial preparation of chromium yellows only began about 1804-1809. Chrome pigments have become obsolete today, they are increasingly being replaced by titanium pigments, zircon, and spinel. Density: 4.80 to 6.90 depending on the variety. oil absorption: 15 to 20% Refractive index: 2.2 to 2.6


178

YELLOW PIGMENTS

Strontian or strontium yellow

Color Index: Pigment Yellow PY 32 77839 Consisting of strontium chromate Chemical Formula: SrCrO4 Toxic Pigment Density: 3.74 - 3.78 Kg / l oil absorption: 20% Refractive index: 1.92 to 2.01 depending on the sample. Created in 1808 by H.Davy, discoverer of the mineral, strontianite. The name comes from a place in Scotland, "Strontian", in Argyll shire, where it was discovered.

Barium Yellow

Colour Index PY 31 77103 Prepared as a pigment the first time around 1809, and used in painting in the first half of the nineteenth century. The barium yellow results from a precipitation of a solution of neutral potassium chromate and barium chloride. Barium Chromate for Chemical Formula BaCrO4. It is a pigment compatible with all binders and pigments.Toxicity of barium chloride salts by ingestion and in contact with skin. The yellow Barium is now replaced by the titanium nickel yellow, however given its unique shade, it seemed important to describe it. Excellent hiding power, but very low coloring power. Refractive index : 1.96 depending on the variety. Oil absorption : 27%.

Strontian yellow

Strontian does not exist in the pure state, it is found in nature, combined with sulfuric acids, carbonic acids, or carbonates of lime, with which it constitutes varieties of aragonite. The "Strontian" yellow is prepared by precipitating a boiling solution of alkaline bichromate with strontium nitrate. This magnificent semi-opaque yellow pigment is not very strong in light, it has a greenish tendency, it must be used as an undercoat of other yellows, such as Naples yellow or cobalt. Therefore useful in the technique of glazes for underwear. The pigment can be protected with a Tinuvin varnish (refracts U.V), so there is no risk of changing the color. Avoid using it with water, because it is soluble in it; In oil, it develops all its tint and it is much more stable in mixture with the Rubens gel. This expensive pigment is very difficult to find, I bought from Sennelier, about twenty years ago, unfortunately it has become impossible to find. Strontium pigments are mainly used to protect aluminum from corrosion. Its shade is unique, it has a texture and a really particular hue that is difficult to transcribe with a photo.

Barium Yellow

RTZ 10C151 Yellow

Colour Index Pigment Yellow PY 227 It is a Sulfide Niobium tin oxide and zinc. RTZ pigments were developed by Shepherd® in the 1980s. It is a high performance, inorganic yellow pigment produced by high temperature calcination. It is chemically inert, stable and resistant to heat and UV. It has exceptional durability and masking power and is generally used in applications where resistance to heat, light, and weather is required. Nontoxic pigments. It is compatible with most resin systems, polymers, pigments and binders. Absorption of oil 11%. Specific surface 3.5 g / m2 Thermal stability 320 ° C. PH 5.4. Density, 5.5

Jaune RTZ PY 227 Yellow and RTZ PY 216 Orange [133]


179

RED PIGMENTS

Red Vermilion genuine

Cadmium red N°4

Red Oxide Bayer N° 180

Red from Sartorius

Red from Pompéi

Red from Pompéi

Molybdenum Red

Red ochre from Roussillon

Sanguine in pieces

Red from Herculanum

Red from Pozzuoli genuine

Cadmium red N°2

Red iron oxide

Red from Herculanum

Hematite

Red Vermilion genuine

Hematite

Venice red

Armenian bolus

Cinnabar


180

RED PIGMENTS

The Cinnabar and the Vermilion

Colour Index Pigment Red PR 106 77766 Chemical Formula HgS Mercury Sulfide Natural mineral pigment, also prepared artificially, but it is called Vermilion. It consists of sulfur and mercury. Described for the first time by Theophrastus in - 315 BC. Mohs hardness = 2.5 Density = 8.1 Oil absorption = 13 to 16% Refractive index between 2,819 and 3,146, one of the highest. Toxicity related to the mercury compound when in pulverulent form. The crushed and grounded mineral had served directly as pigment for centuries. The historical source of cinnabar is the famous Almaden mine in southern Spain, which is still the world's largest deposit of mercury. Cinnabar is found largely in nature and especially in England, Italy (Tuscany "monte Amiata"), Idria in Slovenia (where mercury was discovered in 1497), Kweichow in China where there are remarkable crystals, Japan, California, Mexico, Peru and Nikitovka in Russia. Vermilion is the standard name given in England and the United States to the red pigment based on artificial sulfide of mercury. The artificial cinnabar was made very early; Geber (Jabir), an Arab alchemist of the ninth century mentions a red compound Natural cinnabar ©2016 David Damour formed by the union of sulfur and mercury. The pigment has been known to the Chinese since time immemorial and has long been held in high esteem. When it is grounded gently, its tint approaches the reddish orange. Cinnabar and vermilion are permanent pigments, light has no effect on them. Vermillion is incompatible with lead, chrome yellow, zinc yellow and Prussian blue. It can be used in all techniques. This pigment is of unmatched beauty, it is found in the works of the greatest masters of painting, it is easily recognizable because it radiates. We recognizes its frauds, because in the pure state when heated in a small spoon, it disappears without leaving the slightest trace. Three shades are obtained by crushing the mineral and after levigation, but in this form it differs somewhat from its artificial namesake. It does not keep very long grounded in oil and put in tube, it becomes rubbery and asks to be milled again. It is an irreplaceable pigment on the palette of the painter and the illuminator.

Natural Cinnabar 4 levigations in detail from my second book

Common Vermilion

Genuine Red Vermilion from Sennelier

Chinese Vermilion packaged in small envelopes


181

RED PIGMENTS Molybdenum Red

Colour Index Pigment Red PR 104 77605 Artificial inorganic pigment. Pb MoO4 et PbSO4 Chemical composition of the present variety : 10PbCrO4 PbSO4 PbMoO4 It is a mixture of crystals of chromate, sulphate and molybdate of lead, prepared by precipitation with solutions of lead nitrate and sodium dichromate. Toxic pigment, heavy metals.Density: ~ 6.4 oil absorption: 20 to 30% depending on the sample. Refractive index: 2.55 It is known since 1934-1935

The hematite Fe2O3 is an important ore of trivalent iron III and of iron sesquioxide which constitutes the terminal phase of the oxidation of this one.

Natural Hematite ©2016 David Damour

Hematite contains aluminum, silica, magnesium and calcium. • Sanguine is a peroxide (oxide containing more oxygen than the basic oxides) iron, a mixture of hematite and chalk. • The red bolus are earths derived like hematite from different parts of the world, they are also called "bolus from Armenia", however the bolus, contains less iron than hematite, but more magnesium. Non-toxic pigment. Density: about 4.9 to 5.28 Oil absorption: 18 to 30% Refractive index ~ 1.9 to 2.5 depending on the sample Molybdenum Red

It is a pigment with anti-rust properties. Good chemical stability. Exceptional coloring and hiding power. It is compatible with all binders and with all techniques, however, do not mix it with sulfur compounds, with which it blackens. It is preferable to use it with oil, in sub-layers for vermilion, or madder lacquer or cochineal carmine. It is very strong at light and heat up to 160 °C. It is used in the preparation of printing ink.

Hematite – Sanguine - Red Bolus

Pigment Red PR 102 77491 For natural hematite et PR 101:1 77015 for synthetic hematite. Pigment Red PR 102 77491 natural red oxide. Pigment Red PR 101 77491 For artificial red oxides. The word "hematite" means "blood" in Latin and Greek. An old superstition affirmed that the great deposits of hematite were formed after battles, and by the subsequent blood which accumulated in the earth. Hematite crystals are rare and highly sought after by collectors. Hematite is sometimes used in jewelery or as black reflective stones.

Sanguine in pieces ©2016 Damour

Just grind the mineral in a mortar, then wash it, to make a reddish brown pigment, very useful in skin tones. We make sticks of dry pastel with the sanguine, to draw and we use the red bolus from Armenia to make precious coatings for gold, because it has a very soft and astringent texture that allows to make a sitting to make adhere the sheets of metals with water and alcohol.


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RED PIGMENTS CHEMICAL COMPOSITION OF HEMATITE IN %

Iron oxide III trivalent Fe2O3

81.0

Silicon oxide SiO2

5.0

Aluminum oxide Al2O3

2.5

Calcium oxide CaO

2.279

Magnesium oxide MgO

2.0

Manganese Mg

0.06

Phosphorus P

0.026

Sulfur S

0.005

Water-soluble salts

0.13

Reds from Pozzuoli

1.It is a mixture of red ocher and hematite. The natural version is a natural iron oxide, of volcanic origin found near Naples in Pozzuoli, Italy. Nontoxic. Known since antiquity. This highly stable pigment is compatible with all binders and pigments. oil absorption = 20 to 25% Refractive index = 2.5

1. Red Pozzuoli Mixed

Pure natural hematite

2.The natural red from Pozzuoli consists of iron oxide and other traces of elements due to the volcano located 3 km from Pozzuoli. This red has a fine structure, a good coloring and masking power.

Bolus from Armenia 2.Real Pozzuoli red from the end of the 19th century in a cone (trochisque)


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RED PIGMENTS The Red Synthetic Pozzuoli also said Red of "Mars"

It is a red oxide of artificial iron, it has a very beautiful shade, and an exceptional coloring and covering power. It is a synthetic red oxide that some suppliers name red synthetic Pozzuoli. Pozzuoli Red also called red of March

Herculanum red

Pompeii Red - Herculaneum Red Sartorius Red

Colour Index Pigment Brown PBr 7 77491/77492. It is a natural iron oxide Fe2O3, which was widely used in fresco during antiquity and found from . It is sometimes called Tuscan red or burnt Sienna earth, which is calcined from 350 to 400°C. Tuscan red is a bright red pigment prepared by depositing an organic red dye, such as alizarin, on a red iron oxide base. Compatible with all pigments and binders. Oil absorption between 60 and 80%. Sartorius Red from Sardinia

The Minium or Mine Orange

Pompeii Red

Colour Index Pigment Red PR 105 77578 Chemical formula : Pb3O4 The real minium is a mixture of ortho lead plumbate (80%) and lead oxide (20%).It is known since antiquity.Very opaque pigment, renowned for its antirust properties. It is prepared by air heating of the metal, first transformed into massicot and then into minium. At present, the oxidation is done with oxygen. Grinded with oil and then put into tube, it becomes in ver hard mass, that's why it must be just grinded at the moment of its used (see photo on the next page). Density: between 8.25 and 9.15.


184

RED PIGMENTS

Oil absorption ~ 10%, one of the lowest among all the pigments such as brown hematite iron-chromium PG 17 (Blk) also says Green Black of Chrome hematite who need 9% of oil. Refractive index: 2.4

Cadmium Pigments set

Pigment set for practical testing cadmium pigments

Orange Mine Pigment

Cadmium red in a zirconium matrix

Orange mine taken in mass in the tube 1999

Reds of Cadmium

Colour Index Pigment Red PR 108 77202/77196 et PR 108:1 77202:1 a cadmium co-precipitated with barium. There is also a red pigment PR 113 77201, a mercury sulphide co-precipitated with cadmium sulphide, but with less resistance than Red PR 108. These red pigments are cadmium sulfoselenides of Chemical Formula : 3CdS and 2CdSe They are produced, by co-precipitation with solutions of cadmium sulphate and selenium sulphide, which are calcined in order to obtain different shades. Cadmium reds are much more resistant to light and chemical agents than cadmium yellows. There are several shades of cadmium red : light, medium, dark also called No. 1-2-3. oil absorption ~ 20% Refractive index ~ 2.5 Soluble salts of toxic cadmium. Not compatible with lead and copper. Excellent hiding power and very high tinting strength Heat resistant up to 700°C. I don't use the cadmium pigments.

Red Cadmium Dark

Red Cadmium Medium

Red cadmium light


185

GREEN PIGMENTS

Malachite

Green chrome oxide

Egyptian Green

Emerald green

Verdigris

Green chrome oxide

Volkonskoite

Volkonskoite

Cobalt green spinel

Zinc green

Barium Green

Chrysocolla

Cadmium Green Light

Green chrome oxide

Victoria green

Chrysocolla

Ultramarine Green

Dioptase

Emerald green

Rinmann cobalt green


186

GREEN PIGMENTS The Malachite

Says called green mountain, green from magna. Colour Index PG 39 77492 Malachite is a semi-precious natural mineral composed of basic copper carbonate of Chemical Formula : CO3 Cu, Cu (OH) copper hydrocarbonate. Toxicity of copper compounds. It is toxic, in its pulverulent form, wear imperatively a mask during the manipulation. Pigment of density : 4 Hardness 4 on the Mohs scale Refractive index : 1.8 oil absorption : about 34%

Singularly, malachite has not been widely used in European masters paintings, however, it has been widely used with azurite in western China. It has also been reported in Japan on Buddhist murals of the seventh and eighth centuries. Classical and medieval writings refer to malachite as "chrysocolla", a word derived from Greek for "gold" and for "glue" because the ancients used it with "soda" to paste gold leaf.

Natural malachite ©2016 Damour

Known long before the Egyptians. Malachite is perhaps the oldest known light green pigment. Like azurite, it occurs in many parts of the world where it is associated with deposits of secondary copper ores. Malachite was used in ancient Egypt and was found on a tomb of the fourth dynasty.

Malachite Pigment

This decorative stone, which is then cut and polished, was used mainly in jewelery and ornament. 3 shades are obtained after crushing and levigating the mineral, then grinding it on marble, but do not grind too much, otherwise it loses its lovely shade and it darkens. Due to its refractive index, it is desirable to use it in aqueous techniques although it is splendidly ground in oil.

Malachite is also used in fresco in which it is permanent. Compatible Techniques : Enluminure Oil Acrylic Tempera glue, casein. Malachite pigment

Tube of natural malachite in oil

Malachite oil paint tube


GREEN PIGMENTS Green Chrome Oxide

Colour Index Pigment Green PG 17 77288 Artificial pigment of Chemical Formula : Cr2O3 Consisting of > 98.7 % of chromium III oxide, it is prepared by the reduction of alkaline bichromates, such as ammonium bichromate. There are local deposits of natural chromium oxide in Russia, one of which is called "green Russia", but it is virtually no longer mined. The green chrome oxide is very resistant to light, as well as heat, approximately up to 1000°C. oil absorption ~ 15% Refractive Index ~ 2.55

187

The Green hydrated Chromium oxide or "Guignet's Green " also call Emerald Green

Colour Index Pigment Green PG 18 77289 It is an artificial pigment consisting of chromium oxide (765 vol.), Heated to 250 ° C., with boric acid (121 vol.) And water (114 vol.), which gives hydrated chromium oxide. Chemical formula : Cr2O3H2O oil absorption: 40 to 90% depending on the variety Refractive index: 1.9 to 1.95 It was patented in 1859 by the French chemist, Guignet, however, it seems to have been invented by a process kept secret in 1835 by Pannetier, a Parisian pigment manufacturer. It is very resistant to light, acids and bases, but it should not be heated above 180°C, otherwise he loses its water and blackens. It is compatible with all pigments and binders. It is an indispensable basic green on the painter's palette, as mixed with different yellow, it provides all kinds of greens. It is a rather transparent pigment with deep reflections, but of a sharp tint. In commerce, in the form of ready-to-use paint, it is often replaced by other greens such as heliogene green or obtained by mixing, because it is a very expensive pigment, check the Color Index PG 18 on tubes . Emerald green

Green chrome oxide

The Atacamite

Atacamite occurs at Acatama in Chile where it was first identified. Its synonym is remolinite. It is a copper oxychloride mineral of the chemical formula Cu2Cl (OH) 3 which may contain 60 to 75% copper and about 16% chlorine, having a fibrous or granular orthorhombic-dipyramidal crystal structure. She was known by the Egyptians. It may be associated with cuprite, brochantite, linarite, caledonite, malachite, chrysocolla, paratacamite, botallackite and clinoatacamite. It is also found in Corsica, Quebec, Spain, England and Australia. Theophilus mentions it and calls it Fine Atacamite 0-80 µm "viride salsum". In the Middle Ages there were recipes of green which refer to this mineral very solid to the light. Hardness 3 to 3.5. Density ~ 3.76. Atacamite BY Rob Lavinsky via Wikipédia

Emerald green In full light


188

GREEN PIGMENTS Zinc Green also knows as English Green

It is a mixture of zinc yellow and Prussian blue or heliogene blue, giving cooler shades than chromium oxide greens. It is often very charged ; I prepare it in proportion of 90% Zinc Yellow + 4% Prussian Blue or Heliogene + 6% Lithopone. The word "English" as a result of a pigment is a generic term given by the producers of zinc green and red ocher.The pigments were imported into England, cooked, mixed, and then re-exported to Europe under the name of English red or English green. Oil absorption rate : 30 to 35% Refractive index : 1.7

Ultramarine Green

Colour Index Pigment Green PG 24 77013. It is a pigment, which results from the manufacture of ultramarine blue, a double silicate of aluminum and sodium containing sulfur. The ultramarine green is the first product of calcination in the manufacture of ultramarine blue by the indirect process. The ultramarine green was produced between 1840 and 1960. It was a very important pigment in facade painting and artistic painting. Nontoxic. It can be used with glue, oil, acrylic binders and watercolor. Pigment very difficult to find ( sell it a few year ago).

Green Black Chromium of Hematite

Bluish Cobalt Green A or Rinmann Green

Colour Index Pigment Green PG 19 77335 It is a synthetic pigment, colored with cobalt zincate: CoO, ZnO. It was invented by a Swedish chemist, Rinmann, at the end of the 18th century. 1. It has been artificially prepared since the nineteenth century, by calcining zinc and cobalt oxide, or zinc nitrate and cobalt nitrate, in which boric acid or phosphoric acid is added to enhance the tint. 2. Isomorphous mixture (same structure) of cobalt zincate and zinc oxide heated to high temperatures which can not be separated chemically. The palest hues require larger amounts of zinc oxide. It is a very lightfast pigment. It is not Toxic. Oil absorption ~ 20% Refractive index: 1.9 Pigment compatible with oil, acrylic, tempera, aqueous paints and ceramics. Incompatible with silicates, cement and fresco binders.

Colour Index PG 17 77288. High performance pigment also known as Shepherd Black 10C909A and Dynamix Black 30C940. It is made by high-temperature calcination of chromium (III) oxide Cr2O3 and transition metals with a hematite structure. The black green chromium of hematite is combined with mixed metal oxides such as Al2O3 (alumina), Fe2O3 (iron oxide) or Mn2O3 (manganese oxide). This combination of pigments is effective to simulate the reflectivity of chlorophyll in the visible part of the Green Black Chromium of Hematite electromagnetic spectrum in the part of the spectrum that is visible to the eye between 0.40 μm and 0.70 μm. It is one of the main pigments used in the manufacture of green shadow paint for camouflage and military net. Stability to heat> 800 ° C. Density ~ 5.2 oil absorption 9%, one of the lowest. [23]

The Cobalt Green Spinel

Colour Index Pigment Green PG 50 77377 Chemical composition: CoCr2O4 et Co2TiO4 It is a mixture of cobalt, chromium and titanium.The cobalt green of spinel cobalt (Co) 2TiO 4 is a light green powder produced by the calcination at high temperature of a mixture of cobalt (II) and titanium (IV) oxide in various proportions which lead to the creation of a crystal matrix of inverted spinel. It may comprise one or more modifiers of aluminum oxides Al2O3, calcium oxide CaO, oxides of chromium Cr2O3, oxRinmann bluish cobalt green


189

GREEN PIGMENTS ides of iron Fe2O3, lithium oxides Li2O3, magnesium oxide MgO, Nickel oxide NiO, oxides of antimony (V) Sb2O5, and/or zinc oxide ZnO. Compatible with all techniques. Density: 4.53 Kg / l. Oil absorption : 16 to 22%. Insoluble in water. Perfectly lightfast.

Refractive index 1.55 to 1.90 depending on the variety.

Verdigris

Cobalt green spinel

The Verdigris

Colour Index Pigment Green PG 20 77408 Chemical formula : Cu (CH3COO) 2•[Cu (OH) 2] 3• 2H2O Chemical composition : C4H6CuO4 × H2O, Cu (CH3COO) 2 • [Cu (OH) 2] 3• 2H2O It is a hydrated acetate of divalent copper (II), which is obtained by applying vinegar or bunches of grapes to copper plates in a closed vessel, the thin layer of verdigris is recovered gradually. It is known since antiquity. Toxicity of copper compounds. It is an unstable and highly reactive pigment, which darkens under the action of hydrogen sulphide, nevertheless, it was used much in the Middle Ages in enluminure and decorative painting, as well as in the eighteenth century , in particular, Watteau used it as a green lacquer, moreover you can use it to realize the Spanish oil. If used in oil with the Rubens gel, with shellac or with encaustic, it does not move. It has a very high luminosity of tone, both in oil and in aqueous binders. Care must be taken to insulate the paper supports with a varnish, since the copper acetate makes holes in it. It has a very good resistance to light. Verdigris in full light

Cadmium Green

It is a mixture of 3 pigments. Pigment Yellow Cadmium PY 35 77205 Phthalocyanin blue pigment PB 15:3 74160 Pigment white synthetic barium sulfate PW21 77120. Pigments compatible with all techniques. Very good fastness to light.

Light Cadmium green

Dark Cadmium green


190

GREEN PIGMENTS The Victoria Green or Pastel Green

Colour Index Pigment Green PG 51 77300 Chemical formula : 3CaO·Cr203·3SiO2 It is an inorganic pigment produced by the calcination at high temperature (1150°C.) of a mixture of calcium (II), chromium (III) oxide and silicon oxide (IV), in various proportions to form a crystalline matrix of the spinel-garnet type. It may include aluminum oxide Al2O3, boron trioxide B2O3, calcium fluoride CaF2, cobalt oxide CoO, lead oxide PbO or zirconia ZrO2, as modifiers (see glossary) . It is best to use the Victoria green PG 51 in aqueous techniques because it loses its beautiful tint in the oil becoming darker as the green chrome oxide. Oil absorption : 35% Excellent light fastness. This pigment is compatible with all techniques, even in the ceramic technique, because it is calcined at 1150°C, so it should be suitable for painting ceramic glazes. Grinding of Victoria green in oil. Note as the shade has darken, it is therefore preferable to use it in aqueous techniques such as pastel or enluminure, to preserve its beautiful shade.

Green Victoria Pigment

The Egyptian Green

Colour Index pigment bleu PB 31 77437 Chemical composition : CaCuSi4O10 It is a copper silicate. Cf. Egyptian Blue. It is made as the Egyptian blue by heating a mixture of calcium compounds (carbonate, sulphate or hydroxide), a compound of copper (oxide or malachite) of quartz or silica gel in proportions corresponding to a ratio of 4 SiO 2 · 1 CaO · 1 CuO at a temperature of 900 °C using a stream of sodium carbonate, potassium carbonate or borax. The mixture is then maintained at a temperature of 800°C. for a period ranging from 10 to 100 hours.

Green Victoria grinded with water Egyptian Green in full light


GREEN PIGMENTS

Egyptian Green in Ambient Light

The Volkonskoïte or Volchonskoïte

Chemical formula : Ca03(Cr3+, Mg, Fe3+) 2(Si, Al) 4O10 (OH)2 4H2O Volkonskoye was discovered by Kammerer in the summer of 1830 at Mount Efimiatskaya on the Siberian Ural Mountains (Russia). It was dedicated to Prince A. Volkonskoi, minister and patron of the natural sciences of the Imperial Court of Russia (a generalmarshal during the War of 1812 against Napoleon). It is a chromium mineral often described as a hydrated chromium silicate containing about 7-34% chromium oxide Cr203 which is part of Class VIII of the Silicates and Phyllosilicates of the smectite group. The smectites represent the major part of the products of the superficial alteration. They form in greenish mass in general, ranging from serpentines that are found to about thirty meters deep, up to a few meters to the surface. Among these smectites are found Volkonskoites, whose richness in chromium varies around 34% of chromium oxide Cr203 strongly colored green. It is generally accepted that the content of chromium oxide Cr203 in the Okhansk mineral range is in the order of 15 to 24%, while other Russian chrome clays (known as Sedyuchenko's chromium beidellites (1933)) Contain only up to 5% Cr2O3. Analysis of the mineral by Berthier Silica chrome oxide green Peroxides of iron Magnesia water 98.8 %,

27.2 34 7.2 7.2 23.2

191

Volkonskoite is a clay mineral whose principal coloring component is chromium silicate, found in sandstones, conglomerates and red beds, commonly in the filling of voids of the decomposition of organic matter (wood, etc.). ...) and oxides of iron rubéfiante. The largest deposit of Volkonskoite is located in Mount Efimiatskaya and elsewhere in the Okhansk region of the Kama River in the Perm Basin in the Russian Urals. An area of about 2500 km2 with 70 Volkonskoy deposits, located to the west of Okhansk, between the Kama River and Kirov, which was delineated by Entsov et al. (1952), who also described the geology and petrology of the region where Volkonskoite is found. [69]. The mineral is often associated with chlorite, and tridymite. It is a rare mineral in other parts of the world, deposited mainly in Russia, but is also found in the Belgorod-Dnestrovskii (Akkerman) region of Ukraine and near Gotse Delchev (Nevrokop), Pirin in Bulgaria. Volkonskoite is not very rare in Russia, you can find it quite easily if you are looking for it. The mineral is usually free of impurities and may be used as a pigment without too much preparation. There is some evidence of a green pigment of chromium oxide in some European Renaissance works, but there is little data on the use of this pigment in ancient art. No universally accepted definition of volkonskoye exists to date. The nomenclature of volkonskoite should be examined by the nomenclature committees of IMA and AIPEA so that a simple and precise definition of this mineral is established.[70]

Attila Gazo Volkonskoite from ©Master Pigments

Volkonskoite is considered a very stable pigment. It is not affected by exposure to light. The natural pigment is absolutely permanent. There are no known incompatibilities with other pigments and binders.


192

GREEN PIGMENTS A unique feature of mineral volkonskoite is its high adhesion, which complicates grinding for use as a pigment. One method to avoid this pitfall is to add a small amount of quartz or silica during the grinding of the mineral with the muller on the marble. The addition of quartz does not detract from its qualities which make it one of the best green pigments to use in the first layers as well as in the final stages of the work. Volkonskoite is not toxic, but precautions must still be taken when treating the pigment in powder form, do not inhale the dust. The massive tint of the volkonskoite varies from a luminous olive green to an emerald green, she closely resembles grinded with oil, to a green earth from Verona.

Density : 2.

Volkonskoite Pigment ©d’Attila Gazo from Master Pigments®

The Volchonskoite has a beautiful shade for glaze. Its shade is similar to glauconite, but fresher, more greenish. Its refractive index can vary from 1.70 to 1.90 depending on the proportion of chromium, hence the pigment is rather transparent. In order not to waste its beautiful tint, it would be better to use it in aqueous techniques, where the pigment will develop such a beautiful shade, luminous and subtle of sustained green earth. Painters have always appreciated Volkonskoite as a pigment which gives to the oil a translucent hue of olive hue, which makes it particularly perfect in glazes and Velatura. After drying, the volkonskoite is very stable and keeps its tint indefinitely, this is one of the reasons that made it use in icons painting. Pablo Picasso liked this pigment for its beautiful color and properties, and throughout his career he supplied large quantities of Volchonskoite for his use in painting. Hardness : 2-2.5.

Tint of the Volkonskoite in oil

The Dioptase

Volkonskoite

Volkonskoite to oil with addition of white

Also called emerald of copper, emerald of the poor Mineral of the class of silicates. It is a copper silicate Chemical formula : Cu6•Si6•O18•6H2O. The dioptase is presented in short prismatic crystals and compressed in the free state, but also in the form of crusts. Its modes of deposits are located in the zone of oxidation of copper deposits, in veins of calcite or dolomite. It is found in Zaire, Russia, Chile and Arizona in the USA. It is a very rare mineral, it is particularly difficult to find crystals of a size suitable for the development of pigment. Ref. . The dioptase resists very well to light, but between 350 and 400°C it becomes blue, between 400°C and 800°C it loses its water and becomes black. Density ~ 3.28-3.35. Hardness Mohs ~ 5


GREEN PIGMENTS

193

The Green called "Veronese green"

Magnificent Dioptase

Barium Green

The barium (From Greek βαρυς or barys, heavy) is an element of symbol Ba. The pigment is at the origin barium manganate precipitated by a mixture of solutions of barium chloride and alkaline permanganate, but it also results from the mixture of barium chromates, phthalocyanine blue and strontium chromate. This beautiful pigment, stable to light and moderately covering, has a very fresh shade. It is not found now in pigment powder, but you could meet him, that's why I talk about it.

I do not know why around 1826 pigment manufacturers gave the name of "green Veronese" to a variety of Schweinfurt green, while the real green Veronese already existed, it is simply green earth of Verona, A much diaphanous tone; But the manufacturers of pigments of the time, found it very commercial to give the name of veronese to this pigment not very solid in light, a acetoarsenite of copper precipitated by mixing solutions of arsenite sodic and sulphate cupric that reacted with acetic acid. These greens of copper arsenite are poisons like the realgar. It would seem that was this kind of compounds would have poisoned Napoleon, because the wallpapers of the time were dyed with such pigments. It is possible to make a shade of very fresh green of "Veronese" green, by mixing heliogene or phthalocyanine green with heliogene or phthalocyanine blue, the brightness is adjusted with white. But we can also powdered or pulverized jasper on fresh paint layer, on an undercoat of green earth mix with a little white for example, as Veronese used to do.

The Jasper of Latin and Greek iaspis is a crystalline

iron silicate from a sedimentary and volcanic rock containing ~ 80 to 95% silica, ofPigment "green Veronese" ten classified with microcrystalline quartz such as chalcedones and agates. It may contain clay and up to 20% other minerals such as manganese, lead, copper, antimony, silver, thallium, tin, zinc, etc. Hardness ~ 6.5 to 7. Density ~ 2.65 g / cm3 Refractive index ~ 2 to 2.2 Oil absorption ~ 20 to 30%

Rock of Green Jasper

Barium Green Green jasper


194

THE OCRES

Limonite N°1

Limonite N°2

Limonite N°3

Tawny brown ocher

Hematite

Burgundy Yellow ocher

Red ocher of Roussillon

Dark yellow ocher from italy

Light yellow ocher

Brown ocher of the Elba island

French Orange Ochre

Sanitobre

Verdaccio brown

Verdaccio dark

Verdaccio yellow

Limonite N°4

Roussillon Yellow ocher

Ocher of gold

Pale yellow ocher

Verdaccio greenish


195

THE OCRES

Burgundy Yellow ocher nodule

Sanguine in pieces

Jarosite

Burgundy Yellow ocher

Burgundy Yellow Ocher

Dark yellow ocher from italy

Burgundy Yellow ocher nodule

Light French ocher

Burgundy Yellow ocher

Golden Ocher of the Carpathians

Light yellow ocher

Tawny brown ocher

Sanitobre

Roussillon Yellow ocher

Pale ocher from Cyprus


196

OCHRES AND EARTHS FROM DIFFERENT PARTS OF THE WORLD

The number of ochres and earths is incalculable. Their respective colour indexes are for yellow and orange tints PY 43 77492, for those of red coloring PR 102 77491, for earths of green shades PG 23 77009 and for those of brown and reddish brown shades of PBr 6 to PBr 8. Ochers and earth of all shades are found all over the world. They are found mostly in the mountains and in the vicinity of volcanoes rich in various minerals and rocks, in the bed of rivers, in places often washed and displaced.Ochres and natural earths have a lower coloring power than synthetic oxides, but have superior chemical resistance and abrasion resistance.They are all resistant to light.

Yellow ocher from Amberg in Germany

Orange ocher 120 μm from Castile in Spain

Yellow ocher from Andalusia in Spain

Venetian Red PR 102 77491

Moroccan yellow ocher

Green Earth of Bavaria in Austria Light ocher from germany

Extra fine green earth from Russia

Black earth 80 μm from Andalusia in Spain

Brown ocher of germany


197

THE OCHRES AND THE EARTHS

Yellow from Heydalsvegur

Green from Brimisvellir

Red from Snaefellsjoekull

3 earths of Iceland. The Snæfellsjökull is one of the most renowned volcanoes in Iceland, thanks to Jules Verne who, in his novel "Journey to the center of the Earth", situates the entrance to the center of the Earth at the top of this mountain. The name of the mountain is actually Snæfell jökull which means glacier. In the vicinity of the Snæfell jökull volcano, there is an extraordinary amount of minerals. Dr. (in close collaboration with landscaper Peter Lang) has harvested some of these earths to benefit us. They will be magnificent in enluminure or gouache. As usual, the earths and ochres are rather sublimed with aqueous binders.

NATURALS OCHRES AND EARTHS


198

THE OCRES

Yellow Ochers and the Limonite

Peroxide of hydrated iron : 2Fe2 O3·3H2O Colour Index Pigment Yellow PY 43 77492 for natural ocher and Pigment Yellow PY 42 77492 for synthetic iron oxide. See synthetic oxides. Density : 4.30 Hardness : 5,20 oil absorption : 30 to 35% Refractive index: 2.0 to 2.2 depending on the sample. These are very siccative pigments. Yellow ochres are natural clays as rocks, constituted by ferric hydroxides, mainly derived from Limonite, Goethite and Lepidocrocite rocks. Limonite in particular is rust in its natural state. Its name comes from the Latin "limus": mud, vase. It is very frequently formed everywhere, especially by oxidation of other iron ores to which it superficially gives its color. Its earthy and powdery varieties are called "ocher" or "earth". Limonite often contains impurities of colloidal silica, clay and manganese oxide. [112] Compact and fragmented varieties with sticky luster are called "stilpnosiderites" from the Greek "stilpnos" gloss and "sideros" iron. Hematite is distinguished from limonite, with which it is often found in nature by the color of the powder. The most important deposits of limonite are found in Sweden and Finland where it is called "iron of the marsh" or "iron of the lakes" because it forms at the bottom of certain lakes under the action of microorganisms. I brought back from a trip to Italy very beautiful limonite. Photos adjacent. Limonite contains 48 to 63% iron. The best contemporary natural ochres contain 22% iron oxide, 10% alumina and 64% siliceous sand for Burgundy ocher; For ocher of Vaucluse: 17% of iron oxide of which 22.80% of alumina and 51% of siliceous sand, it will be more transparent than that of Burgundy. If you want to use pigments very rich in iron oxides, then limonite is the best first choice. Ochres are rocks and not minerals. They have been known since prehistoric times. They are treated by separating the coarse impurities by levigation in water. The fine parts are then filtered and dried. Up to 5 shades are obtained per levigation. In Burgundy to the south and north of the Loire River, many mines produced a local ocher very famous in the artistic world, but this one of laborious underground extraction no longer exists, it nevertheless remains a mine currently active And it is possible to obtain ocher from Burgundy (see Suppliers, earths and colors). Currently it is in Roussillon in France in the Vaucluse that ocher is the most exploited. Ocher is found all over the world and there are thousands. Ochres have infinite shades and have an incomparable physical resistance to external aggressions (resistance to abrasion), as well as an extraordinary behavior over time and an incredible lightfastness and stability, if they are used with a durable binder.

Goethite © 2016 Damour. It is from goethite which have been developed synthetic iron oxides

Purified limonite trochisques ©2016 Damour

Limonite 4 levigations ©2016 Damour


199

THE OCRES Red Ocher and Calcined Red Ocher

Yellow ocher of Roussillon Burgundy yellow ocher In ambient light

2 yellow ocher from Burgundy in full light

Colour Index Pigment Red PR 102 77491 It is constituted by iron oxide: Fe2O3 Red ocher is either natural as hematite or other natural oxides or is obtained by heating yellow ocher between 200 and 300 ° C. The grade depends on the cooking time and the cooking temperature and the iron ore composition. There are red ochres and synthetic yellow ochres: red iron oxide, also called red and yellow of March, very coloring, but they are less resistant to wear than natural ocher. oil absorption of 15 to 30% Refractive index: 2.70 to 2.95

Red Ocher from Mexico ©2016 Damour

Red ocher of Roussillon

Common red ocher

Red ocher from Morocco extra-fine

9 months. 100 X 80 cm @ 1993 David Damour – Private collection - France. The pigments used in this oil painting on wood are limonite No. 1 to 4, Pozzuoli red oxide, Prussian blue and white lead.


200

THE OCRES SAHARA Ochre

Colour Index PY 43 77492. Natural yellow ocher French constituted by Fe2O3 + ALO3 + SiO2. Melting temperature ~ 1340 ° C. pH 7. Density : 946 g / liter

It is a common product of the alteration of pyrite and / or the mineral group of Feldspars (based on double silicate, aluminum, potassium, sodium or calcium). Jarosite is a rare mineral, but it is present in small amounts in almost all layers containing iron sulphides. It is often associated with barite, turquoise, galena, goethite, limonite, hematite, and other iron ores. Jarosite Analysis Component

French Ochre SAHARA

Satinobre Monte Amiata satin ocher

This ocher originates from Mount Amiata, an extinct volcano of the Apennines, which culminates at 1,738 m; It is located near the Maremma, Val d'Orcia and Val di Chiana on the border of Tuscany near Umbria and Lazio. sells this beautiful ocher.

Satinobre Ocher orange gold from Monte Amiata

The Jarosite

Colour Index Pigment Yellow PY 43 77492 Chemical formula : KFe3(SO4) 2 (OH)6 or (K, H3O)Fe3(SO4)2(OH)6 The jarosite which is used as pigment is sulphate hydrate of iron and potassium. Most of the minerals in the natural jarosite group are considered stricto sensu as solid jarosite solutions : KFe3+3(SO4)2(OH)6, of natrojarosite : NaFe3 + 3(SO4) 2(OH) 6 and hydronium jarosite : (H3O) Fe3 + 3 (SO4) 2 (OH) 6. The Jarosite was named in 1852, according to the typical locality of its discovery, Barranco Jaroso, in the south of Spain. It can also be named according to its geographical position. The main source of iron (Fe) in its deposits is pyrite, which on contact with oxygen oxidizes and in contact with water releases ferric iron as well as sulphates and generates acidity. The generation of acidic drainage produces water rich in iron and sulphate. These highly concentrated solutions lead, according to the physicochemical parameters, to several types of secondary or tertiary minerals, including Jarosite and / or goethite. Jarosite is therefore a secondary mineral, formed under certain conditions and under arid climate.

Potassium oxide K2O Iron oxide (III) Fe2O3 Sodium oxide Na2O WATER H2O Sulfur trioxide SO3 Alumina AL2O3 Total in%

% 4.80 45.7 0.22 13.51 32.5 0.09 96.73

Jarosite is the clearest natural yellow ocher, it does not have this orange tint of other ochres.Jarosite was identified as a pigment in the Middle East on wall paintings as well as on Egyptian temple walls at Karnak. In a Roman villa in France, microscopic particles of hydronium jarosite ([K, Na, H3O] Fe3 [SO4] 2[OH] 6) were also discovered on frescoes and pigments during excavations in Pompeii Walsh and all.2004). Currently, it is found in Egypt, Spain in Barranco Jaroso, Cyprus, New Mexico, Canada, North America and Russia. Jarosite deposits are also found in the Achi-Say layers of Kazakhstan and Zhuravlinskogo in the Russian region of Perm.

The Pale Ocher or Limonite of Cyprus

Due to the political situation in Cyprus, mining of its rare and beautiful deposits is little exploited, but a small quantity of manual production is available from certain suppliers such as . There are likely to be other natural ocher deposits of this clarity throughout the world, but the Jarosite of Cyprus has always been famous for its unique tint. It is resistant to atmospheric agents and light. It has good hiding power.

Natural jarosite pigment Under natural light


201

THE OCRES Density ~ 3.2. Hardness ~ 2.5 to 3.5 Molecular Weight ~ 500.81 g Refractive index ~ 1.713 to 1.820 Oil absorption ~ 54% = 50 grams of pigment ~ 30 ml of oil (10ml black oil weighing 9.3 grams for 0.93 of density). Natural jarosite under artificial light

Sanitobre under ambient light Sanitobre in full light

Verdaccio

Name given to a mixture of equal parts of ocher, black and Saint John white (Cennino Cennini). Originally these shades were used in fresco, then later in tempera and then in oil. The pigments are greenish to warm brown, similar to dark earth. They are used in underlayments to highlight the warm shades of skin tones to obtain subtle and realistic flesh effect. Verdaccio dark greenish

Verdaccio yellow

Natural jarosite under natural light

Tube of pale ocher of Cyprus grinded with oil

Sanitobre

The Sanitobre is a kind of ocher, resembling limonite in its color and ferrous composition. It has the same properties as ocher but its tint is very dark in oil, while with an aqueous binder it retains its tint. It was a term used in the sixteenth century to designate a dark ferrous ocher. Refractive index: 2.0 to 2.2. Oil absorption: 44%

Tube of Sanitobre grinded with black oil Verdaccio dark

Verdaccio brown


202

THE SYNTHETIC IRON OXIDES - PIGMENTS OF MARCH The Pigments of "Mars"

The Pigments of "Mars" The term "Mars" comes from the literal Latin "Crocus martis" used by medieval chemists to refer to artificial iron yellow, but it is now a generic term for certain artificial iron oxides, which exist in many dyes, yellows, reds, oranges, browns, violets and blacks represented by synthetic oxides. See the above images.

Orange of Mars iron oxide 960

Brown iron oxide 660

Black of March

The manufacture of the synthetic iron oxides is performed according to 3 different methods, using raw materials such as scrap metal or byproducts for pickling steel or recovering liquors during the production of titanium dioxide TiO2.

In the solid state

This process involves the calcination of iron oxide, sulphate and chloride in an oxidizing atmosphere to give reds, browns and blacks.

Precipitation and hydrolysis

The iron salt solutions are mixed with alkali and are then air-fired at temperatures above 90°C, which precipitates the desired pigment. This method is used to produce yellows, orange, reds and blacks.

The Laux Process

It represents the conversion of the well-known Bechamp reaction on an industrial scale for the reduction of iron from nitrobenzene to aniline, which produces iron oxide as a residue. The incorporation of iron or aluminum chloride in the reduction process produces high quality yellow and red iron oxide pigments.

Mars brown iron oxide 610

Iron oxide Gamma

Red iron oxide

The different Synthetic Iron Oxides

• Red Oxide PR 101 77491 = Fe2O3 xH2O • Yellow Oxide PY42 77492 = FeO xH2O • Brown Oxides PBr6 77491, 77492, 77499 = Fe2O3xFeO yH2O • Brown Red spinel PBr 11 77495 = MgO Fe2O3 • Black of March PBk 11 77489 et 77499 = Fe3O4 • The Caput Mortuum PR 101 77491 = Fe2O3 is an artificial oxide of a purplish brownish tint obtained by calcination of iron sulphate, it resembles the Brown iron oxide 660. There are various shades of reddish and dark.

Yellow iron oxide 920

Mars Yellow-orange Mars Violet

Caput Mortuum purple


203

EARTHS

Natural sienna earth

Iseo reddish-brown earth from Lombardy

Calcined Umber

Clay green earth

Glauconite

Verdaccio dark greenish

Natural Glauconite

Verdaccio brown

Natural Umber from Cyprus

Verona Green Earth

Aegyrine

Verdaccio dark

Green Earth Burnt

Brown from Otranto

Epidote

Yellow Verdaccio


204

EARTHS Earths of Siena - Umbers and others

Sienna natural C.I Pigment Brown PBr6 77 492. Burnt Sienna Pigment Brown PBr 7 77491 et 77492. Raw umber, burnt and greenish Pigment Brown PBr 8 77728 et 77730 Nature provides many earths of all ints and shades. The shading of raw earths vary from brown to gray through green. Many earths can be used to make paint. The coloring of these powders is usually caused by divalent iron (II) silicate. Personally I also use glauconite as green earth, its name comes from the Greek "Glaukos": greenish blue, alluding to its tint. After levigation it is one of the most beautiful green earths. The possibilities for a chemist to recognize and describe these rare materials are very difficult. The basic element of green minerals is frequently iron, chromium or nickel.

Individual deposits of green minerals are rare, but on a regional scale they are rather abundant. Epidote, for example, may be found in veins and thin layers up to 1 centimeter thick in the region around Livorno in Italy. Many Earths are locally crushed and used as pigment, therefore not well-developed commercially. If you have the opportunity to go to the mountain, take surface Earths and test them by levigation, you can get beautiful and very subtle pigments.

Natural Italian Siena of Badia province of Bolzano

Natural Umber Greenish dark PBr 8 77728

Sienna natural

In Russia, for example, a chrome local deposit is exploited for artistic purposes, its chemical composition is a silicate iron hydrated chrome, the color of the pigment is similar to green viridian. In Italy, many green and greenish minerals deposits were available in Tuscany during the Middle Ages. The medieval mineralogist could easily distinguish between a green earth and a green copper compound. Green earths are often named after their first places of origin: Green earth of Bohemia, Cyprus, Verona, Earth of Siena, Badia, etc.

Verona Green Earth, the pigment used by Paul Veronese (born in 1528) and the Green Earth of Bohemia

Also called Celadonite. Colour Index Pigment Green PG 23 77009 Chemical formula : K (Mg· Fe2+) (Fe3+ Al) [(OH) 2|Si4·O10] and also K (CA1·Fe3+) (Fe2+·Mg) (AlSi3·Si4) O10 (OH) of monoclinic system, its hardness is about 2, its refractive index is 1.68 and its oil absorption rate is about 80%. The green earth is essentially a mixture of glauconite and celadonite minerals, a complex amalgam of magnesium, hydrated iron, potassium and aluminum silicate. These deposits, known since antiquity, lie north of the mountain of Verona at Monte Baldo in Italy. The bluish quality, the best earth from Verona is no longer accessible, since the landslide of 1922, result of a great earthquake, however some suppliers have it in reserve. This earth is very subtle for skin tones. Grinded with clear oil, she is beautiful, because she has a unique shade of dark emerald green. The green earth of Bohemia, dull and more yellow replaced it on the palette of the painter. The burnt green earths are calcined natural green earths, which chemically transforms the ferric hydrate compound into ferric oxide. It is possible to produce green called "Veronese", a shade of fresh green by mixing green and blue heliogene (but also by sprinkle jasper as Veronese used to do) and with a refractive index of 2 to 2,2 and oil absorption between 20 and 30%.


205

EARTHS

This is a clay mineral known at all times, which is also found in sediment in some rivers. Its name comes from the Greek "Glaukos" (green blue) derived directly from its greenish tint. After levigation and purification of pure glauconite, you will obtain up to 3 shades, ranging from dark green to light green. It can be used in all techniques and with all binders, because it has a great chemical inertia, but care must be taken by purification with water, to remove the soluble salts and the sandy impurities present in the mass. She must be boiled, filtered and then levigated.

Genuine Verona Green Earth

Green earth from Cyprus embellished with cobalt blue, it is then called earth of Nicosia

Genuine Verona Green Earth

Raw natural glauconite ©2016 Damour

Oil tube of Green Earth from Verona Note its magnificent shade of dark emerald green

The Glauconite : silty green earth

Colour Index Pigment Green PG 23 77009 It is a mineral ferric (III) iron and ferrous iron (II) silicate of greenish tint with micaceous structure of Chemical Formula (K, Na)2 (Fe3+, Fe2+, Al, Mg)3[Si3 (Si,AL)O10](OH)2,4 H2O. It is an hydrous iron and magnesium aluminosilicate of density : 2.79 and refractive index 1.62. with an important oil absorption for natural green earths, up to 80%. They are conventionally in the form of dark green grains of 0.1 to 3 millimeters in diameter in marine sediments of 50 to 500 m depth, find in sand, clays, carbonates, sometimes associated with phosphate or epigenized minerals (a chemical phenomenon consisting in transforming the chemical nature of one element by another without changing its shape).

Purified natural glauconite ©2016 Damour

glauconite grinded with oil


206

EARTHS Earths of Cyprus : Natural Umber and Green Earth Colour Index Pigment Brown PBr 8 77728 et 77730 Refractive index : 1.87 to 2.17. Oil absorption up to 50%. Mixture of iron oxide and manganese of Chemical Formula Fe2O3MnO2nH2O Elle contient de 45 à 70 % de fer : Fe2O3 et de 5 à 20 % d’oxyde de manganese MnO2 et moins de 10 % de silice, d’alumine, etc. ... She contains 45 to 70% iron: Fe2O3 and 5 to 20% manganese oxide MnO2 and less than 10% silica, alumina, etc. ... She has a strong tone and good opacity. It is a earth of very high quality, among the most fixed. There are 6 different shades of Cyprus shade, ranging from natural variety to burned variety. It is also prepared chemically, by precipitating, with potash, a solution containing a mixture of iron sulphate and manganese, the precipitate is washed, dried, and then calcined. There is also a green earth from Cyprus PG 23 77009 impossible to harvest, because of the political situation of the country, however sells a little of this quality.

The calcined umber

Colour Index Pigment Brown PBr 8 77728 et 77730 Density: 3.64 Refractive index: 2.3 Oil absorption: up to 35%. No Toxicity. Originally the Umber was exploited in Nocera Umbra in the province of Perugia which forms the Umbria in Italy, now it also comes from Turkey. Derived from the Italian word for the umber, "ombra", in reference to its obscurity and its natural depth. It comes from colored reddish brown clay with oxide of iron and manganese hydrate. This calcined variety is obtained by heating the earth of natural shade, which has the consequence of destroying the organic impurities, by changing its color and especially making it less greedy in oil, this makes it more fixed and more suitable for this technique . She has always been known and used. Excellent coloring power, but low hiding power, which instead targets her for glaze. It is a very siccative earth, because it contains manganese. Pigment stable and compatible with all binders and pigments. After harvesting the earth, it is pulverized and then the earth is boiled in water in order to remove the impurities by hot filtration, only if we desired to preserve it raw, otherwise it is calcined directly. We obtains by levigation up to 4 shades. Common calcined Umber

Raw umber from Cyprus

Dark Green Earth from Cyprus

Green Earth from Cyprus

Calcined Umber photo in full light


207

EARTHS Sienna natural and Sienna burned

Colour Index of the Natural Sienna Pigment Brown PBr 6 77491, 77492 et 77499 and for burnt Sienna Pigment Brown PBr 7 77491 et 77492. Sienna consists of iron oxide and manganese dioxide, but also contains clay. It originally comes from Sienna in Italy, but is found all over the world, such as green earths, umbers, yellow ochres and red ochers. Like the raw umber, the earth of Sienna is calcined to make it more stable and change its color. The burnt Sienna earth contains 30 to 48% of red iron oxide and much more manganese dioxide than natural Sienna, so she is more drying. Refractive index : 2 to 2.2 Oil absorption up to 80% for the natural variety, 60% for the burned variety. Natural sienna Under artificial light

The Epidote The Epidote

Colour Index Pigment Green PG 23 77009 Epidote is a word that comes from the Greek epidosis (increase), of very complex composition, it is constituted by silicate of calcium, iron and aluminum also known as piemontite (of Aosta) when it is manganesiferous, But of red-brown to very dark red. It is a mineral species of the group of silicates of the subgroup of sorosilicates. It forms a series with clinozoite when it does not contain iron.Chemical formula : Ca2 (Al, Fe III) 3 [OH (SiO4) 3] ou [(Si2O7) (SiO4)] O (OH) Al2Ca2 (Al, Fe3+). It occurs mainly in metamorphic rocks derived from impure calcareous rocks or from rocks rich in feldspar. The largest deposits are found in Europe in Italy in Piedmont and on the island of Elba in Tuscany, but are also found in Austria, Russia and Cornwall, in Isere Rhône-Alpes in France. Described by René Just Haüy in 1801. This yellowish green pistachio pigment was widely used by Gothic painters of the Middle Ages, and is found in many paintings of green meadows. Refractive index 1.715 to 1.797. She is very hard to ground on the marble because of it's hardness of 7 but she is so beautiful that it is worth the effort.

Burnt Sienna

Epidote powder

Green Earth Burned

Epidote block


208

EARTHS

Iseo brown Reddish brown earth umber from Lombardy

It is a earth of a unique shade, reddish, local and regional exploitation of Iséo, small Italian town of Lombardy. It is rather transparent in oil, so ideal for glacis and for watercolor. Pigment stable and compatible with all binders and all pigments. It has a very good stability to light. As all local earth, therefore rare, its price is quite prohibitive (92 € / kg), compared to more common earths, such as raw Siena (30 € / kg).

Important deposits of Ægyrine are found in Norway at Telemark, Porsgrunn, Langesunds fjorden, Bjørkøya, Haoya, Haoya West; Malawi, the Zomba district on Mount Malosa, Arkansas in the United States and the Kola Peninsula in Russia. Gyrin is not considered to have been used as a pigment.It is a mineral, a relic of the green earths, which are themselves derived from the erosion of alkaline rocks, in which the ergyrin may be present.It is a frank green earth, interesting to use in conjunction with glauconite, because it has a fool proof stability. Compatible with all techniques and binders. Mineral refractive index: 1.760 to 1.805 Hardness of the mineral: 6. Density: 3,5

Brown Iseo in full natural light

The Ægirine

Colour Index Pigment Green PG 23 77009 borrowed from the green earth. Chemical formula : NaFe3+ Si2O6 with traces of Al, Ti, V, Mn, Mg, Ca, K, Zr and cerium. The Aegirine is a mineral species from the group of silicates subgroup of inosilicates family pyroxene, clinopyroxene subfamily, often found in association with augite.The constitution of Ægyrin Augite can be related to the characteristic chemical composition of the host rock, ie the high iron/iron oxide ratio, Fe203/ FeO and iron oxide and oxide of aluminum Fe203/ Al203. His name comes from Ægir, the Scandinavian God of the sea.The Aegirine occurs in pegmatites and in alkaline igneous rocks such as nepheline syenites and alkaline granites which generally occur in areas of continental extension.The Aegirine is an iron that contains a silicate, which forms elongated crystals that have a needle-like structure. The color of the very hard particles is dark green.

Ægirine By Rob Lavinsky iRocks.com via Wikimedia

Ægirine pigment 63 μm


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GRAY PIGMENTS

Greenish gray schist flour

Greyish schist flour

Ceylan Graphite

Graphite

Gray from Mels

Manganese gray

Spinel gray

Onyx gray

Onyx gray

Blue gray slate

Schist flour

Gray granite

Schist flour

Gray lead

Schist flour very light

Gray of Beaune from Burgundy


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GRAY PIGMENTS The Natural Grays

There is no gray Colour Index, but black PBK.Found in some commercial paints of "Slate Black" meaning "black schist" with Colour Index PBk 19 77017 to some black and gray make up the composition of mixtures include "the gray of Payne", to mention the best known, that shares the Colour Index with some slates consisting of hydrated aluminum silicate. Nature provided all over the world, various grays, coming from minerals, rocks, limestone deposits, slates, volcanic rocks and granites. The tints of these rocks embrace all the shades which goes from gray to light green depending upon the source of the materials. Many of these powders can be used to make paints, especially with aqueous binders. The coloring of these powders is often caused by silica and alumina, hence they are generally poorly colored and not very covering.

Ardennaise's earth- Rotten earth - Gray lead

Kind of natural earth made from slate and from Ardennaise earth, very subtle, grinded in oil it has a greyish hue.I use it in shadows and skin tones. It is a rather transparent earth. Link to buy it : http://www.moulincouleurs.fr/fr/terres-et-ocresnaturelles/30-terre-pourrie-2076.html These lands and natural clays are extracted from various quarries. These deposits are found in the Ardennes, Burgundy, Germany and even in India, in fact all around the world. See Suppliers. Oil absorption is about 40% Refractive index of 1.80. Gray lead

COMPOSITION OF AN ANGEVINE SLATE Silica 50 % Alumina 30.1 % Iron oxide 8% Magnesia 2.3 % Potash 3 Soda 1.3 % Water 3.3 % Various 2% However, grays are often named after their extractive locations or chemical constituents such as manganese gray or earth (umber, Sienna, as originally). Individual deposits of gray minerals are rare, but on a regional scale rather numerous. Clay is a sedimentary rock composed largely of minerals, usually silicates of more or less hydrated aluminum, which has a laminated structure (phyllosilicate), which explains their plasticities.

Rotten Earth

Ardennaise Earth

Onyx Gray

Onyx is a variety of Agate, which is itself a variety of chalcedony, consisting of more or less pure silicon dioxide of Chemical Formula SiO2 Hardness: 6½ to 7. The Colour Index of the silica is Pigment White PW 27 77811

Schist flour extra light

Colour Index PBk 19 77017 Borrowed from the Slate Black Hydrated silicate of aluminum and magnesium. It is a mixture of hydro-silicated alumina, natrolite, a mineral species from the group of zeolites, silicates of the tectosilicates subgroup of the chemical formula Na2 (Al2 Si3 O10).2H2O and natural feldspar of the chemical formula (Ba,Ca,Na,K,NH4)(Al,B,Si)4O8 which is also a mineral of the tectosilicate family, the composition of which is that of a sodium, potassium or calcium aluminosilicate. It has à low coloring power.

Onyx gray Onyx gray in full light


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GRAY PIGMENTS Onyx flour is silky and ideal for coatings and water techniques. It can be advantageously used as an undercoat, for laying silver sheets and for precious coatings.

Slate Grey

Schistous clay ot shale, C.I PBk 19 77017 whose color varies according to the origin and the content of various impurities. Dark bluish gray = Breton and Touraine region slate. With very dark varieties, we obtain powder called "black slate". Purple gray = Ardennaise slate. For 1000 the composition of the slate from the Corrèze, seems to be the purest : Silica 619 Alumina 192 Lime 12 Magnesia 27 Potash and Soda 45 Loss on fire 28 parts, the lowest of the 4 slates.

The best graphite comes from Sri Lanka, it is called "Ceylon" (it is the purest constitued by 98% of carbon), but it could be extracted all over the world. Synthetic graphite, with the same composition as natural graphite, is obtained by the graphitization (baking between 2600°C and 3000°C.) of a mixture of petroleum coke and pre-fired pitch (bitumen). It is more pure (about 99% carbon) than natural graphite and offers better electrical conductivity and greater chemical resistance. Graphite is used in the manufacture of pencils and alkaline batteries. In industry, graphite is used for the manufacture of anticorrosive and antistatic paints, it is the pigment which constitutes the pencil and which is also used to draw the sketck of our drawings on canvas, however, strokes should be fixed to avoid bleeding and/or to prevent run-down of the graphite in the underlying layers of the substrate. Low density which varies from 2.1 to 2.3 Low hardness of 2 on the Mohs scale Very high melting point of 3500 ° C. Refractive index : 2.70

Flour gray schist

Natural slate

The Graphite or Plumbago

Graphite in pieces

Colour Index Pigment Black PBk 10 77265 Chemical formula : C Carbon black rich in pure carbon up to 99% according to the varieties and, whose ash content varies from 0.40 to 5.73%. At the end of the eighteenth century, the Swedish chemist Carl Wilhelm Scheele proves that the plumbago (which he used to write) does not contain any lead, it is an oversight, but is in fact constituted by a particular and relatively pure crystalline form of carbon. The term "graphite" was invented in 1789 by the German mineralogist Abraham Gottlob Werner, inspired by the Greek word "graph in" which means "to write". Natural graphite is subdivided into 3 varieties: 1. Graphite in flakes 2. Vein graphite 3. Amorphous graphite The graphite is remarkable for its inalterability and its properties to guarantee rust iron and cast iron objects. Graphite


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GRAY PIGMENTS Manganese gray

Colour Index Pigment Black PBk 14 77728 Composed of Manganese dioxide : MnO2 It is naturally produced by pyrolusite and polianite, but the commercial product is generally prepared from a mixture of manganese dioxide, hausmannite, braunite and other manganese ores. Dioxide is the most common manganese compound in nature, the so-called "pyrolusite" constitutes the main ore of the metal. Manganese dioxide is insoluble in water, nitric acids and sulfuric acids. Its density is 5.026

Melting point : 535°C with release of oxygen and formation of manganese sesquioxide Mn203. Change of state from 527 °C (decomposition) PH value : 8

Grinding of manganese gray with oil

As a pigment, the manganese gray has a very beautiful hue with bluish reflections. It is totally stable to light. Compatible techniques : Oil, Acrylic, Tempera, Aqueous paints, Fresco, Ceramic, Silicate paint, Gouache.

Manganese gray

It is a very reactive compound because of its powerful oxidizing power. It can react hotly on many reducing substances, including sulfur, hydrogen sulphide, sulphides... It also acts as oxidizing agents for certain acids. This characteristic is used as a desiccant for paints and varnishes, as it is an excellent oxidation catalyst for oils. CHEMICAL COMPOSITION OF THE PIGMENT Element

Quantity in %

MnO2

minimum 88,50

MnO

Approx. 0.75

Fe2O3

Approx. 0.56

Al2O3

Approx. 1.0

CaO

Approx. 1.0

PbO

Approx. 0.29

As

Approx. 0.02

Spinel Gray

Colour Index PBk 26 77494 Chemical formula : MnO Fe2O3 The iron black manganese spinel is an inorganic pigment. It is a product of the high-temperature calcination reaction in which divalent manganese (II), trivalent manganese (III) oxide, iron (II) oxide and (III) is incorporated in various amounts And homogeneously to a chemical bond between a metal and an interdiffused non-metal to form a crystal matrix of spinel. Its composition may comprise one or more modifiers of Al2O3, CoO, CuO, NiO3, SiO2 or TiO2 Used during the creation process in order to adapt its properties. This cold tone pigment with pretty bluish reflections is very coloring. The iron black manganese spinel is very resistant to light and it is compatible with all binders and pigments. Pigment resistant to temperatures up to 540ºC. Density : 5,4 Kg / l Oil absorption of 48%.


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GRAY PIGMENTS Gray from Mels

Colour Index Pigment Black PBk 19 77017 Types of schistous clays of the Swiss Alps, constituted mineralogically by a mixture of hydrated aluminum silicate, quartz and mica. Approximate formula : Al2SiO8(OH)4. Very high stability to light.Compatible techniques: Oil, Acrylic, Tempera, Aqueous painting, Fresco, Cement, Ceramics. Gray from Mels

Spinel gray

Gray of Beaune from Burgundy

The Gray of Beaune of Burgundy is a warm light gray. The tonality of the powder is similar to chalk, greyish, but with more force. The tonality of the pigment can vary from binder to binder, becoming warm gray brownish to oil, and lighter in aqueous binders. If the pigment has a granulation of less than 80 μm. It is easily diluted in aqueous binders, although pieces remain visible on strokes. With watercolor, the paint can granulate slightly. The Gray of Beaune can also be grinds with oil, but like cobalt and ultramarine pigments, it would have a tendency to sink. The color is maintained better when a coagulator is added to it, for example a little Laponite or wax, which also makes it possible to stabilize the suspension with the oil if the paint is put into tube. This pigment is suitable for watercolor and aqueous techniques, for tempera and acrylic dispersions in order to preserve its beautiful tint.

Gray of Beaune

Payne's Gray

As it is found on all suppliers colour chart, I give you here its composition. It is a mixture of 3 pigments, an heliogene or a phthalocyanine blue with carbon black and quinacridone violet : PB 15 74160 + PBk 6 77266 + PV 19 46500

Payne's gray


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ORANGE PIGMENTS

Mine Orange

Titanium Orange

Titanium Orange

Yellow of March

Orange for glaze

Natural Crocoite

Mine Orange

Orange for glaze

transparent Orange

Titanium Orange

Gamma Orange Iron Oxide

Cadmium Orange

Mine Orange

Molybdenum Orange

Titanium Orange

Molybdenum Orange


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ORANGE PIGMENTS The Titanium Orange

Colour Index Pigment Brown PBr 24 77310 Artificial inorganic pigment of titanate oxide of chromium antimony : (Ti, Cr, Sb) O2 chemical characteristic : Ti= Titane Rutile – Sb : Antimony – Cr : Chromium et O : Oxygen Pigment insoluble in water, it is also very resistant to acids and alkalis. Excellent resistance to light. It is a pigment of original shade derived from titanium, it is therefore very stable in oil, but it tends to powder, the use of clear or black oil stabilizes it and makes it very pleasant to use, it Keeps its beautiful sonority in oil, in which it gives splendid colour planes. It is compatible with oil, acrylic, tempera, water paint, fresco, cement, ceramic, silicate paint and paint on glass. No Toxicity. Density: 4.4 Refractive index ~ 2.5 oil absorption ~ 18-40%

Mars Orange and Orange for glaze

Colour Index Pigment Yellow PY 42 77492 and Pigment Red PR 101 77491. Artificial iron oxide Fe2O3. No Toxicity. Density of 3.7 Kg/l at 20°C. The "Orange of Mars or Mars Orange" were developed between the eighteenth and nineteenth centuries. They are prepared by aqueous precipitation of iron salts such as sulphates with an alkali and then calcining this ferrous sulfate FeSO4, with which red and orange shades are obtained, according to the calcination time and the variety of iron used. These pigments of paler shades than ochres and natural earths were produced, among other things, to compensate the wear and tear caused by natural ochers on the granite rolls of mechanical mills of paints for artists and building manufacturers. All Mars pigments are artificial iron oxides, therefore they are much more transparent than their natural homonyms thus more useful in glaze. Iron oxides are compatible with all binders and pigments. Oil absorption ~ 54% Refractive index ~ 1.5

Orange for glaze

Titanium Orange

Titanium Orange

Mars orange yellow


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ORANGE PIGMENTS Molybdenum Orange

Colour Index Pigment Red PR 104 77605 This pigment was patented in 1930 by the German chemist Lederle. Chemical composition : Pb (Cr, S,Mo) O4) Chemical formula : 7 Pb CrO4, 2SO4PbMoO4 It results from the co-precipitation of lead chromate and molybdate, in a range of varying concentrations of lead chromate 69-80%, lead sulfate 9-15% and lead molybdate 3-7%, other substances 3-13%. molybdate lead chromate pigments advantageously replace the reds and oranges of chromium. COMPOSITION OF THE FINAL PIGMENT Component

%

Pb

59

CrO4

27

SO4

4

MoO4

2

Toxicity of lead. Solubility in water of PbCrO4 (major component): 0.058 mg / L (at 25 ° C) and 0.17 mg / L (at 20 ° C) Solubility in water of PbSO4 (minor component): 42.5 mg / L (at 25 ° C) Melting point> 800 ° C Density ~ 5.30 to 6.10 Refractive index ~ 2.55 Oil absorption ~ 15 to 30% The permanence of the pigment is increased by several ways either by addition of stabilizing agents such as zinc salts or by precipitation of the lead chromate with a coating of lead sulphate or by the encapsulation of the pigment with silica. It has a high hiding and coloring power. It may be affected by hydrogen sulphide. Very good fastness to light. This very bright and beautiful pigment, is used to prepare oil paints and inks. Personally, I use it also with enluminure to replace the orange mine and for oil glazes.

pallette in pearwood with Molybdenum Orange

Molybdenum Orange

Molybdenum Orange oil tube


ORANGE PIGMENTS Orange Mine or Minium

Colour Index Pigment Red PR 105 77578 Chemical formula : Pb3O4 The true minium is a mixture of lead ortho-lead (80%) and lead protoxide (20%).It is prepared by air heating of the metal, first transformed into massicot then into minium or the orange mine is prepared from PbO by oxidation by heating it in air to 500 ° C., Unreacted excess is removed by dissolving PbO in acetic acid. In its modern version, the oxidation is performed by the injection of oxygen. Mineral minium (pictured below) may have been used as pigment in Antiquity, Pliny quotes it (77 AD). The synthetic variety was known as red lead, it is one of the first inorganic pigments to have been made with Egyptian blue and green. Very opaque pigment, renowned for its anti-rust properties. Density between 8.25 and 9.15.oil absorption ~ 10%, one of the lowest. Refractive index ~ 2.4

The Crocoite

Colour Index Pigment PO21 77601 and PY 34 77600 et 77603 For synthetic lead chromate. Its name comes from the Greek "saffron" as referring to his red-orange hue. Crocoite is one of 25 chrome minerals that are all rare. It is a chromate of lead. Chemical formula : PbCrO4 The Crocoite was discovered in a Russian gold mine in Sverdlovsk in 1770. It also comes from other countries such as Brazil, Hungary, Germany, South Africa and Australia,where we currently find (2016) the most beautiful specimens. Notable occurrences also exist in the United States at Inyo, Riverside County in California and Maricopa County in Arizona. The Adelaide mine is the most prolific source of superb crocoite specimens from Dundas in Tasmania.[81].

Crocoite By Didier Descouens via Wikimedia Commons

Natural Orange Mine BY Andrew Silver. Collected at Broken Hill, New South Wales, Australia via Wikipedia

Orange mine pigment

Its red-orange translucent prismatic crystals form in deposits of lead ore. As a secondary ore, crocoite occurs in the oxidation zones of massive hydrothermal deposits. It most often forms the basis of chromium-rich chemical environments from the oxidation of galena. Crocoite is associated with other secondary minerals such as wulfenite, pyromorphite, cerusite, limonite (a hydrous iron oxide mixture), vanadinite and a number of rare chromates, including ochroite of composition PbCrO4.PbO, a name given by Klaproth in 1803 to the Swedish mineral now called cerite, from which it extracted a new earth (from the impure oxide of cerium) which he named "ochroiterde" because of Its yellow ocher tint. With a density between 5.9 and 6.1, crocoite is among the most dense of all translucent minerals. This unusual density is due to the high atomic weight of lead (202.7), its main elemental component. Due to its density, the crocoite has a particularly high refractive index of 2.31 to 2.66, which is close to that of diamond. Hardness: 2.5 to 3.0

217


218

ORANGE PIGMENTS COMPOSITION OF A STANDARD CROCOITE

Component

%

CrO3

30.3%

SiO2

1.10

PbO

68.35

Total

99.80

In 1761, the German mineralogist Johann Gottlob Lehmann (1719-1767) identified the crocite as a new mineral after studying samples of the locality of the Tsvetnoi mine near Sverdlovsk, R u s s i a . Suspecting that this new mineral contains lead, Lehmann calls it "red lead of Siberia". In 1770, the German scientist Peter Simon Pallas (1741-1811) crushed specimens of the same site into a bright yellow powder which constituted a superb pigment in painting and for the Genuine Adelaide Crocoïte powder dyeing of fabric, this pigment rapidly gained popularity throughout Russia and Europe. But the true composition of the crocoite remained a mystery until 1797, when the French chemist Louis-Nicolas Vauquelin (17631829) treated samples of "Siberian lead red" with acid to produce an oxide that contained an unknown element at this point. Vauquelin named this new element "chromium," according to the Greek "Chroma," meaning "color", alluding to the bright colors of its compounds. He also demonstrated that the "Siberian red lead" was in fact lead chromate. In 1832, the French mineralogist François Sulpice Beaudant (1787-1850) gives the "Siberian lead red" its first formal mineral name "crocoise", from the Greek "krokos" saffron, a reference to the color of the powder. This name was changed to "crocoite." Crocoite was initially the only known source of chromium. From 1780 until 1850, the crocite of Russia

and Germany was the only source of chromium necessary for the manufacture of yellow pigments in chromate of lead for paints and dyes. The importance of Crocoite as a chromium ore came to an end in 1850 after the discovery of large deposits of iron (chromium oxide) chromite ore. Crocoite was used occasionally in art painting, probably that of the Beresovsk mine in Russia although this mine was not always active. A synthetic crocoite, a yellow lead chromate of CI Pigment Yellow PY 34, was widely used as a pigment. The natural crocoite is available at at a price of 41.65 € per 10 grams, such a price is due to its rarity, but the pigment is so pure and it is so beautiful that it can justify it[89].

Cadmium Orange

Colour Index PO 20 77202 for pure cadmium sulfoselenide and PO 20:1 77202:1 for Barium Sulphide and PO 23 77201 varieties with mercury sulphide and PO 23:1 77201:1 cadmium and mercury sulphide coprecipitated with sulphate of barium. It is an intermediate pigment between cadmium red and cadmium yellow : a cadmium sulfoselenide. Orange cadmium pigments exhibit excellent light fastness, are opaque, bright and have a high coloring and covering power. There are 4 cadmium orange, from 0- 0.5-1 and No. 2. Orange tints are more numerous in organic and synthetic varieties. See Dyes and lacquered pigments.

Cadmium Orange Nº0

Cadmium Orange


219

VIOLETS PIGMENTS

Light bright cobalt violet

Manganese violet

Light red ultramarine violet

Reddish ultramarine violet

Dark cobalt violet

Dark cobalt violet

Dark bright cobalt violet

Mars violet

Violet of the French Riviera

Vesuvianite

Mars violet

Manganese violet

Light bright cobalt violet

Ultramarine red

Light bright cobalt violet

Mars violet


220

VIOLETS PIGMENTS Manganese violet

Colour Index Pigment Violet PV 16 77742 Also Called Violet of Burgundy, Violet of Nuremberg. Chemical name: Manganese (III) ammonium pyrophosphate prepared by the action of phosphoric acid on manganese dioxide and ammonium chloride. Chemical Formula : P2O7MnNH4 No toxicity Known since 1868 (Nuremberg) Density : 2.70 Refractive index : 1.8 oil absorption : 25 to 33% Good resistance to acids, low resistance to alkalis, resistance to temperatures up to 250°C in air. Excellent resistance to direct light. It is a pigment which has a rubbery structure under the muller, in oil. It is a very siccative pigment. It must be grinded with raw oil only, I have already ground this violet and then put it into tube, it has become hard in only few months. It has a pretty hiding power, of a blue violet purple lacking radiance (dull, leaden). This pigment of acid tint is very useful in undercoating for other violets such as cobalt violet. It look like the dark cobalt violet, but does not have its rheological characteristics. It is beautiful in the technique of pastel. Techniques : Oil, Acrylic, Tempera, Waterbased paint. Check the pH of the binders.

COMPOSITION OF VESUVIANITE

Calcium Aluminum Magnesium Iron Silicon oxygen Hydrogen Fluorine

~ 27 % ~ 8% ~ 3% ~ 3% ~ 17 % ~ 40 % ~1% ~1%

The Vesuvianite was discovered and described in 1795 by the German of Saxony, Abraham Gottlob Werner [1750-1817], an eminent mineralogist who was appointed in 1775 as inspector of mining and professor of mineralogy at Freiberg in Germany. He named the Vesuvianite after the locality of his first discovery in Italy, at the volcano of Vesuvius near Naples in Campania. Four years later, the renowned French mineralogist and crystallographer René Just Haüy (1743-1822) suggested that it be called "idocrase" because its crystal grooves are similar to those of certain minerals that crystallize in other systems. Both names were used interchangeably until 1888, when mineralogists formally confirmed his original name of "vesuvianite".

Manganese violet

The Vesuvianite

Mineral vesuvianite is a double silicate of alumina, iron, magnesium, calcium hydrate and oxyfluoro silicate, which may contain copper, beryllium, chromium, manganese and boron. The vesuvianite is of the class of silicates belonging to the mineralogical group of sorosilicates (double tetrahedral silicate, the simplest sorosilicates from the structural point of view comprise the S2O7 group of two SiO4 tetrahedra associated with an S. The vesuvianite can also be called "idocrase," referring to vesuvianite gem forms and comes from the Greek word "eidos", which means "form" and "krasis", blend or mixture ; alluding to its crystalline form that shares the characteristics of both the nesosilicates and the sorosilicates. Chemical formula : Ca10 (Mg, Fe) 2 Al4 (SiO4) 5 (Si2O7) 2 (OH, F) 4 ou (Ca10Al4 [MgFe] 2 Si9O34 [OH4].

Vesuvianite

The areas where vesuvianite is found most are : Coahuila in Mexico, Quebec, Canada, Rio Grande, Brazil and Castrovirreyna, one of the seven provinces of the Huancavelica region in central Peru . In U.S.A, the Vesuvianite is found in California, Arizona, New Hampshire, Rkansas, Idaho, Washington, Nevada and Texas. Other localities provide some mineral and are found in Italy, Austria, Switzerland, Sweden, Russia, Pakistan, Japan, China, Kenya and Namibia.


221

VIOLETS PIGMENTS Hardness: 6 to 7 Density: 3.32-3.43 It is a pigment which it is preferable to use after grinding and washing of the mineral, in aqueous or lean techniques, in order to preserve its beautiful violet tint. Pigment available from .

Violet of the Côte d'Azur

Also named "light caput mortuum". This pigment is between ocher and radiolarites. [113] It is similar to mica and is colored by iron and manganese. Its highly colored mineral deposits are of only local importance, in Switzerland near Sargans and between Nice and Turin in the Alps, where there are currently two natural deposits. This pigment with fine reflections can be used in aqueous techniques and in the enluminure for subtle carnations. Techniques: Acrylic, Tempera, Water-based paint, Fresco.

chloride (5%) heated at 150 ° C. for 24 hours, cooling and then washing and drying the material. No Toxicity. Density: 2.35. Refractive index: 1.5 oil absorption: 35%. Resistant up to 260 ° C. Excellent resistance to light even direct. Excellent resistance to alkalis, but low in acids, it produces hydrogen sulphide or hydrogen sulphide in its contact. Possible techniques : Oil, Acrylic, Tempera, Aqueous Painting, Fresco, Silicate Binder.

Light red ultramarine violet

Violet of the Côte d'Azur in bloc.

Ultramarine violet

Violet of the Côte d'Azur pigment

The Ultramarine Violet

Colour Index Pigment Violet PV 15 77007 It is a sodium aluminum sulfosilicate. There are 3 shades from light reddish to reddish with medium brightness. It is made by mixing ultramarine blue and ammonium Reddish ultramarine violet


222

VIOLETS PIGMENTS Reddish ultramarine violet

Colour Index Pigment Red PR 259 77007 Chemical family: sodium aluminum sulfo silicate Chemical formula : Na6Al6Si6O24S4 et Na7Al6Si6O24S3 Composed as the complex aluminosilicate ultramarine blue containing an alkali sulfide, but unlike it, it contains more sodium and hydrogen. No Toxicity. Refractive index : 1.5. Oil absorption : 50%. Excellent resistance to light and alkalis but lower resistance to acids, with which it releases hydrogen sulfide, a highly flammable toxic gas; Check the pH of your binders before mixing with them. This pigment has integral component since its composition is original as well as its method of manufacture and that it has a colour index. During the grinding on the marble, a strong odor of sulfur emanates and in contact with the iron, it blackens spatulas, palette knives, etc. ... It is very beautiful in pastel stick. Techniques compatible : Oil, Acrylic, Tempera, Waterbased paint, pastel. Avoid using it in encaustic because there is toxicity of the irritant gases of sulfur dioxide that can be generated if the pigment undergoes a chemical change at a high temperature by other combustible materials. In any case, it is better not to take the risk.

Ultramarine red

Ultramarine red

Mars Violet

Colour Index Pigment red PR 101 77491 Chemical Formula : Fe2O3 Like all "Mars" pigments, it is an artificial iron oxide. It is obtained by heating ferrous sulfate (Mars yellow) to high temperature. The first step consists in precipitating iron hydroxide by making it originally in ferric form as the Mars yellow, then it is by calcining this Mars yellow that various shades are obtained by dehydration. The more the pigment is heated, the more it turns from red to violet then to black.They are very strong pigments compatible with all binders and all pigments. Oil absorption ~ 20%

Mars violet


223

VIOLETS PIGMENTS Potter's Pink or Sicocer® F Pink 2302

Colour Index Pigment rouge PR 233 77301 Chemical composition Chromium silicate tin Chemical Formula (SnCr) O2 ou Ca (Sn, Cr) Si05 Forme une poudre micronisée. Densité : 3,90 kg/l. Forms a micronized powder of density : 3,90 kg / l. It is produced by high temperature calcination of tin oxide IV and chromium III oxide in the presence of alumina, calcium oxide II, silicon oxide IV or marble flour, which makes it possible the creation of a crystal structure of tin or titanium. After the reaction, the product is washed to remove excess chromium salts. By changing the proportion of tin oxide and/or chromium oxide, various grades are obtained.

There are basically two versions of potter's rose, a luminous version and a darker variant, the two shades resemble Ultramarine red when wetted with a binder and the dark variety looks to be mistaken of the March violet. Many modern inorganic pigments belong to a broad group of mixed MMO metal oxides or the Pics family, complex inorganic pigments. The Potter's pink being the first representative of this family of pigments, invented from the middle of the XIXth century. It was the only luminous pink for watercolor in England from the eighteenth to the nineteenth century. It seems to have been used more frequently in the mid-nineteenth century.

Bright Potter's Pink

The Potter's Pink was invented in England around 1780 circa by an unknown potter from the Staffordshire. In the nineteenth century Winsor & Newton proposed in his catalog a watercolor painting under the name of "pinkcolor". This pigment in its modern version is manufactured by BASF (Germany) under the name Sicocer F Pink 2302.

dark potter's Pink < 38 µm

With a subtle hue of pink, Potter's pink is a truly original pigment, especially the clear version, the darker version is more common, as it can be found in synthetic iron oxides like the Mars violet, see the photo on left.

Potter's Pink

The grains of this pigment are very hard, due to the use of quartz during its realization, which can be noticed during its fine grinding. Its opacity is moderate, but it is much better with aqueous paints; It is a pigment more suitable for velatures than for glacis. This pigment is hard to find in modern technical literature. Its relatively high price (20 € / 50 g) is due to its complicated preparation, and on the other hand because of its rather confidential availability. This pigment advantageously replaces the madder lacquer mixed with white or iron oxides. Originally this pigment was mainly used in ceramics like zirconium white, and it was frequently used as underglaze. It was also used for painting on porcelain and for printing ink. It is an absolutely stable pigment with all binders and with all painting techniques.


224

VIOLETS PIGMENTS

The Violets of Cobalt

Colour Index Pigment Violet : PV 49 77362 for the brilliant bright cobalt violet. PV 14 77360 for the bright cobalt violet. PV 14 77362 for the dark cobalt violet. Phosphate of cobalt hydrate or not according to the desired shade. There are 3 different shades. 1 : Red : (PO4) 2CO3 8H2O toxic 2 : Dark Violet : (PO4) 2CO3 4H2O toxic 3 : Bright Violet : (PO4) 2CO3 no toxic It would seem to be non-toxic in its modern form at least the bright clear version of this pigment. The pigment was invented in 1858 by the French chemist Salvetat. Refractive index: 1.7 Oil absorption ~ 47% for PV49, the addition of a little silica or aluminum stearate stabilizes the pigment during grinding. Excellent stability and very good siccativity. It is a pigment of all beauty, the brilliant bright variety is the purest. I noticed that this violet does not like iron tools, as well as the pigments containing it, tools turn black. Compatible techniques : Oil, Acrylic, Tempera, Aqueous paints, Varnish paint, Enluminure.

Brilliant bright cobalt violet PV 49

Dark cobalt violet PV 14 77362

Grinding of brilliant bright cobalt violet in oil

Bright cobalt violet PV14 77360

Oil tube of brilliant bright cobalt violet


225

BROWN PIGMENTS

Intense manganese brown

Brown iron oxide 686

Dark manganese brown

Brown iron oxide 655

Iron and zinc brown

Iseo brown

Chromic Pyrite

Brown iron oxide 660

Brown iron oxide 640

Brown Chrome Oxide of Hematite

Van Dyck brown reddish

Brilliant brown of Zurs

Vandyke brown Ferrocyannure

Brown chrome iron and zinc

Brown Chrome Oxide of Hematite

Brown Fauve


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BROWN PIGMENTS

The Browns of Manganese

Colour Index Pigment Brown PBr 8 77728 and 77730 and PBr43 77536. It is a manganese oxide (II, III), the natural mineral hausmannite of Chemical Formula Mn2+Mn3+2O4 or artificial Mn3O4, a manganese dioxide, precipitated by action, on a solution of manganese chloride and Sodium carbonate solution, containing some of an alkaline hypochlorite.[112] Manganese is harmful. Mohs hardness of ore ~ 5,5 Density ~ 4.86 Kg / l

Brown Manganese used for making cave paintings

It is a very stable pigment and very solid to light, moderately transparent, and which advantageously replaces the calcined umber earth. It is a deep brown pigment with a warm and full tonal balance, and with high coloring power (PBr43 artificial variety), which is used as a substitute for bitumen, which is detrimental to oil paintings. Refractive index: 1.9 to 2.1 depending on the sample. Oil absorption ~ 20ml of walnut oil per 100 grams of pigment, or 18.6%, much less than umber earth.

Dark manganese brown, a synthetic oxide of manganese and iron that I use to replace the calcined umber too much greedy of oil. Colour Index PBr43 77536 of Chemical Formula FeMnO3, it consists of manganese oxide and iron. It is a pigment with exceptional coloring and covering power. It is available from under the reference 48330 oxide of manganese brown 645 T

Etiquette for manganese brown oil tube PBr43

Intense manganese brown from Morocco Pbr8

Intense Manganese Brown grinding with oil


BROWN PIGMENTS Brown pigments with spinel phase, hematite phase and rutile phase Spinel browns are artificial pigments created after the 1960s and prepared by calcining intimately a mixture of metal oxides at temperatures of 800 to 1400 ° C. During the calcination process, a chemical compound is formed with its own crystal structure, such as spinel, rutile or hematite; The addition of colored ions of various metals gives their colour to these pigments. The desired shade is obtained by selecting specific metal oxides. These oxides are made from metals such as chromium, nickel, antimony, titanium, manganese, cobalt, aluminum, zinc, iron, copper, praseodymium, zirconium, yttrium, etc. ... The resulting product is ground to a fine powder so that the particle size is optimal. Properties of spinel pigments • Good heat stability • They are insoluble • Excellent chemical resistance • They do not bleed • They do not migrate • Good Refractive index • Good dispersibility • Strong covering power • Bright colors Oil absorption: 9 to 30% depending on the variety Refractive index ~ 2 to 2.2 depending on the variety These pigments are part of the family of high-performance pigments, also known as PICs for Pigments Inorganic Complex.

Zinc Iron Brown with spinel phase

Chemical composition : Fe2O4Zn Colour Index PY 119 77496. The iron-zinc brown spinel is prepared by calcining zinc (II), iron (II) oxide and iron (III) oxide in various proportions which create, by ionic bonding, a homogeneous crystal matrix with a structure of spinel. Modifiers such as: Al2O3 or other substances such as: InO2, NiO, SiO2, SnO2 and / or TiO2 may be involved. Density: 4.60 Oil absorption : 20%.

Iron-zinc brown with spinel structure

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The Brown Chrome-Iron Spinel

Colour Index PBr 29 77500 This pigment is part of the PICs pigments. [23] The PBr29 has a shade corresponding to Pantone 497 It is a mixed phase pigment based on iron oxide and chromium oxide, corresponding approximately to formula (Fe, Cr)2 O3. Oil absorption 18 %.

Brown chrome iron spinel PBr 29

Brown Chromium iron and zinc with spinel phase Colour Index PBr 33 77503 This pigment is part of the complex inorganic pigments PICs. Chromium, iron and zinc brown spinel (Zn, Fe) (Fe, Cr) 2O4 Is prepared by calcining at high temperature a mixture of zinc (II), iron (II) oxide, iron (III) oxide, chromium (III) oxide in variable proportions in order to create A crystalline spinel matrix. Its composition may comprise one or more modifiers of Al2O3, nickel oxide NiO, silicon dioxide SiO2, tin dioxide SnO2 and/or titanium dioxide TiO2. Oil absorption : 15 à 25 %.

Pigment PBr 33 Brown Chromium iron and zinc with spinel phase


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BROWN PIGMENTS Inorganic Van Dijck Brown

Colour Index Pigment Brun PBr 9 77430 This brown is copper ferrocyanide : CuSO4 + Fe2 (CN)6. The genuine Brun Van Dijck of Colour Index Pigment Natural 8 : NBr8 77727 Is a kind of lignite, consisting of earth, peat, iron, alumina and silica. sells under the name Van Dijck Brown, a brown from the Czech Republic, which is incompatible with oil. The reddish inorganic variety comes from strong calcination, until sintering, of ocher, followed by grinding. The synthetic variety comes from colcotars, calcined or natural vitriol, chalcitis which is a ferrous oxide (containing copper, which is calcined) or residues of sulfuric acid of very deep reddish brown color, Van Dijck brown is a frank pigment, pleasant to use, but very difficult to find pure in the form of pigment. Oil absorption : 30 à 40 %. Brown from Zurs

Iron Brown or Prussian Brown

It is simply, calcined Prussian blue. You can very easy produce it yourself, in a melting-pot, with a muffle furnace. According to Jean-François Léonor Mérimée (1757-1836), a French painter and chemist, making this bleu succeeds only if the blue of Prussia contains a certain proportion of alumina.

Brown iron oxides 610, 640, 655, 660, 686

These are all mixtures of red + black + yellow synthetic oxides depending on the shade which is usually reddish brown from light to dark. All these mixtures are available from .

Brown iron oxide 610

Colour Index Pigment Red PR 101 and Pigment Black N°11. Pigment Red 101 (Fe2O3) + Pigment Yellow 42 (FeOOH) + Pigment Black 11 (Fe3O4)

Van Dyck Brown Ferrocyannure 1996

Brown from Zürs

This pigment is an exfoliating mica mineral, brown and reddish slate of Austrian origin. It consists of radiolarites. [113] Radiolarites are primitive gravel beasts. They are present in hard, red-brown slates and contain mica [115]. The color of the pigment is due to iron and manganese. The deposit of this brown from Zürs is at the top of Lechtal, Austria. Very good resistance to light. Compatible with oil, acrylic, tempera, aqueous paints, fresco, cement, ceramic, silicate binders.

Brown iron oxide 610.


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BROWN PIGMENTS Brown iron oxide 640

Blend of C.I. Pigment Red 101 (Fe2O3) + Pigment Black 11 (Fe3O4).

Brown iron oxide 655

Blend of C.I. Pigment Red 101.77491 (Fe2O3) + Pigment Yellow PY 42.77492 + Pigment Black 11.77499 (Fe3O4).

ver à otrante, cette ocre presque partout où se trouve des calcaires, spécialement après la chute de pluie en automne, car le sol a fraîchement a été lavée par l'water. La couleur brun reddish de l'ocre ressemble à du sang coagulé qui donne un pigment qui peut être utilisé avec toutes les techniques picturales et avec tous les liants.

Brown ocher from Otranto

Pyrite Chromique

Brown iron oxide 655

Brown iron oxide 660

Blend of Pigment Red PR 101.77491 (Fe2O3) and pigment noir PBk 11.77499 (Fe3O4).

Colour Index Pigment Brown PBr 46 774945 Consisting of iron and chromium with a spinel structure of Chemical Formula : MnFeCr2O4 This chromium iron and manganese brown is prepared by calcination of chromium (III), iron oxide (II and III) and manganese oxide (II and III) in various ratios, thus creating a matrix in the form of crystalline spinel. There is also a version made with zinc oxide. This is a magnificent pigment, similar to the dark greenish shade earth. It is part of the family of high performance pigments (PICs). Chromic Pyrite in full light

Iron oxide brown 660.

Otrante brown

Colour Index PBr 7 Natural brown earth from Otranto. Otranto is an Italian city in the Province of Lecce in Apulia, which gave its name to the Otranto Canal which separates Italy from Albania.The site of Otranto was certainly occupy since the Palaeolithic and the Neolithic, it is a site that has a rich and long history. Cette terre brune contient des dépôts de chaux qui constitue parfois des sédiments sous forme de petits agrégats ronds d'oxyde de fer, que l'on prénomme "pépite". Ces minéraux furent utilisés durant le Moyen Âge comme fondant pour le fer. On peut trou-

Chromic Pyrite In ambient light


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BLACK PIGMENTS

Black earth from Rome

Black iron oxide

Manganese black

Covellite

Spinel Black PBk 26

Atramentum

Spinel Black PBK 26

Manganese black in full light

Manganese black

Magnetite

Spinel Black

Black earth from Rome

Black iron oxide

Black Stone from France

Spinel Black PBk 28

Magnetite


BLACK PIGMENTS

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Black Magnetite

Color Index Pigment Black PBk 77491/77492/77499 From the Greek, "magnes" which means magnet. Magnetite is a natural mineral consisting of magnetic oxide from the oxide family. Membership of the spinel group.

Magnetite © 2016 David Damour Pigment that comes from the mineral that my mineralogist brought me from a campaign Very nice Magnetite By Rob Lavinsky via Wikipedia

The magnetite originates from Magnesia in Thessaly (Greece), it takes its name from Mount Magnetos ("Great Mount"), a mountain particularly rich in iron. She has been known since at least the Iron Age. Pliny the Elder also mentions it in AD 77. Magnetite is a mineral species composed of ferrimagnetic iron oxide (II, III) of Chemical Formula Fe3O4 or Fe + 2 Fe2 + 3 O4 (sometimes written FeO Fe2O3), with traces of magnesium Mg, zinc Zn, manganese Mn, nickel Ni, chromium Cr, titanium Ti, vanadium V and aluminum Al.

TYPICAL CHEMICAL COMPOSITION Element

Pourcentage

Iron protoxide

50,50 %

Carbonic acid

37,4 %

Silica and clay

6,4 %

Lime (CaO)

2,4 %

Manganese

0,8 %

Phosphorus

0,6 %

Magnesia

Traces

Density ~ 5.18 - Hardness 6.00 to 6.50 Refractive index ~ 2.42 - Oil absorption ~ 15% Nontoxic. It is a very stable pigment, after levigation and removal of impurities. Compatible techniques: Oil painting, Acrylic, Tempera, Water based paints, Fresco, Cement, Ceramic, Silicate paint, Glass paint, enamels.

Pigments with a spinel structure

These are minerals of volcanic origin, magnesium aluminates (MgAl2O4). Most spinels are colorless, although some are very colorful thanks to a supply of various ions during their genesis. These colored spinels also give precious stones such as rubicella for example, it is a yellow or orange red stone and the deep black pleonast, with iron content, which comes from Ceylon. Thus, the famous red stone of the English crown is not a ruby, but a spinel. Depending on which elements are in trace amounts, aluminum, iron, chromium, vanadium and titanium spinels can be distinguished. The shades obtained range from red to pink thanks to the ions of chromium and vanadium; orange by a significant portion of vanadium ; blue, purple and blue green with more or less significant parts of iron; blue by 0.001% cobalt and 0.4 to 3% iron ; green thanks to iron and manganese. Spinels are mixed with metals before being heated to 1200-1600 ° C, causing ion exchange. These metal ions remain embedded in the structure of the minerals after cooling. the pigments are then washed and ground. Spinels have a hardness degree of 8 and are not attacked by acids and soda. These pigments are used to tint ceramics but also for making fashionable jewelry. Spinel pigments can be mixed with all binders, they have a very high resistance to light, weathering and chemicals. They are considered nontoxic. They are the most stable of all existing pigments with ochres and earths.


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BLACK PIGMENTS

Blacks of Spinels

Colour Index Pigment Black PBk 26 77494 Colour Index Pigment Black PBk 28 77428 PBk26 is a ferric manganese with a chemical composition (Fe, Mn) (Fe, Mn) 2O4 and it belongs to the copper manganese iron spinel system. PBk 28 is a copper chromate with the chemical formula CuCr2O4. This chromium spinel black is obtained by high temperature calcination of a mixture of copper oxide and chromium oxide in varying proportions to create a crystalline spinel matrix. The formulation can include one or more modifiers such as iron oxide Fe2O3 or manganese oxide MnO. The manganese iron spinel black PBk26 (Fe, Mn) (Fe, Mn) 2O4 is made by high temperature calcination of a mixture of divalent and trivalent ferric iron oxides or of ferrous iron, manganese in different amounts for create a crystalline spinel matrix. Its composition can include one or more modifiers like Al2O3, CoO, CuO, NiO3, SiO2 or TiO2 used in the creation process to adapt its properties. The PBk26 pigment is characterized by an exceptionally intense black tint. If you want real black you have to use this one. Heat resistance above 500 ° C. Density: 4.5 Kg / l (± 0.1) Hardness : 8 (Mohs) Refractive index : about 2.5 Oil absorption : 47% Particle size : <0.5 µm pH: 6 to 8

PBk 26 spinel black He is a very deep black called "true black"

Covellite or Indigo Copper

It is the natural form of a copper sulphide which is also called cupric sulphide. Color Index PB 34 77449 for the black mineral variety and PB 34 77450 for the synthetic variety. The covellite owes its name to an Italian mineralogist Niccola Covelli (1790-1832), who discovered it. It is a mineral species that is found at vesuvius near Naples. it is composed of divalent copper (II) sulphide, of formula Cu2S with traces of iron, selenium, silver and lead. It is the first natural superconductor. The color of the pigment is dark gray. The mineral occurs as scaled crystals with a bluish metallic luster. Depending on the environment, it presents various tones, which range from red to purple. It is a rare mineral sometimes used for its copper ore.

PBk 28 spinel black is more bluish than the other black Spinels Covellite


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BLACK PIGMENTS Black Iron Oxide also called Mars Black

Color Index Pigment Black PBk 11 77489 for the synthetic magnetite variety of Chemical Formula Fe3O4 consisting of black synthetic iron oxide with traces of SiO2 and Al2O3 for the natural variety. It is a pigment obtained chemically by precipitation of iron and aluminum salts which was formerly naturally extracted, its deposits are no longer exploited. Refractive index: 1.9 to 2.1 Oil absorption: 25 to 30% Black iron oxide

Bornite

Bornite is a mineral formed from copper sulfide of Chemical Formula Cu5FeS4 with traces of silver, germanium, bismuth, indium and lead. Its name is borrowed from the Austrian mineralogist Ignaz von Born, given by another mineralogist Wilhelm Karl Ritter von Haidinger who described it in 1845 and dedicated it to his colleague. Bornite can be found associated with Chalcopyrite, pyrite, iron and copper sulphides, garnets, calcite, wollastonite and quartz. Notable deposits of bornite important in Austria, Belgium, Canada and France.

Bornite

Manganese Black

Color Index PBk 14 77728 for the natural variety from pyrolusite and Pigment Black PBk 33 77537 the synthetic variety, a mixture of manganese oxide with a high percentage of iron oxide (up to 60%). The active ingredient in manganese is derived from pyrolusite (MnO2), psilomelane (MnO2, H2O), hausmannite (Mn3O4), rhodochrosite (Mn2 + CO3), rhodonite (MnSiO3) and Jacobsite, an ore of iron manganese oxide which belongs to the group of spinels. Manganese is often associated with iron ores. These so-called metallurgical ores have contents exceeding 35% manganese and are intended for the manufacture of ferroalloys. Rich deposits have contents greater than 44% manganese and can reach 57%. Main producers: Comilog (Gabon), Samancor, Assoman (South Africa), BHP (Australia), CVRD (Brazil). Manganese has a stable isotope 55, it is the second most abundantly found naturally occurring metal on earth after iron. The manganese reserves on earth are estimated at nearly 5 billion tonnes. See http://www.societechimiquedefrance.fr Manganese is often associated in its constitution with other black manganese compounds such as jacobite (Mn2 + Fe2 [III] O4) and in the oxidation state (Mn2 +, Fe2 +, Mg) (Fe3 +, Mn3 +) 2O4 . Manganese was widely used by prehistoric painters, but first it was used by peoples in ceramics, in the Near East in glazes from the 7th century (Schweizer and Rinuy 1982). It was prepared with manganese ores to produce a dark brown. Currently, it is also used as a siccative in oils, however it should be reserved for dark shades and shades. As a pigment for painting, it was patented in England in 1871 by Rowan. Manganese black is a blackish gray pigment with a chemical composition of MnO2 derived from natural or synthetic manganese dioxide. Harmful by inhalation and ingestion.

Manganese Black PBk 14


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BLACK PIGMENTS The Black Stone

Close-grained clay shale, consisting of carbon C containing siliceous particles SiO2 and bituminous matter, which came from quarries in Piedmont near Pinerolo. Cennino Cennini talks about it at length in his book "il libro del arte". [24.1] This black stone powder, agglutinated and shaped into a pencil that is rubbed on the paper, leaves traces of a beautiful velvety and greasy black.

Noir de manganese en pleine lumière

It should be ground exclusively in raw oil, as it is a very siccative pigment. pH: 4 to 5 in a 200 g / l aqueous solution at 20 ° C. Density of 3.125. Molecular weight of manganese = 86.94. Refractive index: 1.9 to 2.1. Oil absorption: 25 to 30%. See the browns.

Black Earth from Rome

It is a mixture of calcium carbonate, manganese and iron, very dark, colored by manganese dioxide, which is mainly used in frescoes and in oil painting, which I found after 20 years of absence, in 2017, at Restauro-online. Lab data = L 27 a 1.14 b 4.69 Refractive index 1.8 Oil absorption 30 to 40%.

Terre noire de Rome

Pierre noire de France

This black stone was widely used in the 15th century by designers and craftsmen. Its deposits are no longer exploited. Currently there is a somewhat oily stone that comes from France, Thuringia in Germany and Andalusia, but it is a little thinner than its Italian namesake. It is also called Ampelite when the proportion of pyrite, an iron sulphide FeS2 is greater.

The Inkstone or Atramentum

Product of the reaction of oak tannic acid in an iron salt solution. Atramentum is a deep black material, which differs from carbon blacks and iron oxide black. Historically also called "ink stone", it is grayish black in aqueous binders. It can be corrosive to paper supports. However, this pigment develops a deep and incomparable hue with oil or acquires a glassy appearance in oleoresinous binders. It is a very bright pigment. Not to be confused with Flame Black.

Atramentum


MICA PIGMENTS - PEARL - PEARL GLEAMS - GLITTER

Fuchsite green quartz mica

Scales of mica Muscovite

Muscovite

Fuchsite green quartz mica

Colibri royal-gold

Violet iron mica

Colibri Bronze

Mica Silver blue

Phlogopite mica

Colibri copper-gloss

Fuchsite green quartz mica

Violet iron mica

Chroma yellow-gold

Mica copper

Muscovite mica

Magic indian

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MICA & PEARL PIGMENTS The word mica comes from the Latin "mica" (plot). It is a mineral formed mainly of aluminum silicate (kaolin) and potassium (alkali metal). Mica is referenced in Color Index Pigment White PW 20 77019 represented by muscovite, a mineral of the silicate group (subgroup of phyllosilicates). It is a hydroxylated silicate of aluminum and potassium, chemical composition H2KAl3 (SiO4) 3. Its name is inspired by the translation of vitum muscoviticum (Moscow glass), the mineral was used as glass, especially for stoves. The mica in flakes or "flakes" comes originally from by-products of the exploitation of other substances (kaolin for example), that is to say from rocks containing high proportions of mica such as muscovite and phlogopite which is a kind. of mica, fluoride can be contained in small amounts in almost all mica, be it phlogopite, muscovite (the most common) or others. The most common white mica is muscovite, a silverycolored mineral which is cut into sheets, these "flakes" can be used as they are, but are most often sprayed, either dry ("dry-ground") , either by wet way ("wet ground", thinner), or micronized. Powdered muscovite mica is a mixture of 36% aluminum oxide (alumina) and 47% potassium oxide (silica acid). The remainder of the 17% is divided into 10% potash and small amounts of iron oxide, fluorine, magnesium oxide, water and soda. Natural mica and consequently large particles can damage oil paint films. Very fine, micronized particles of mica titanate, as well as pearl glow pigments are more suitable for oil painting. Mica is chemically inert. Density 2.9 Mohs hardness: 2.5 to 3.0

1-3 mm Muscovite mica scales

CHEMICAL ANALYSIS OF A PHLOGOPITE MICA SiO2

40,7 %

Al2O3

15,8 %

MgO

20,6 %

K2O

10,0 %

FeO

8,9 %

Bao

0,5 %

Na2O

0,5 %

TiO2

1,5 %

Cr2O3

0,2 %

NiO

0,3 %

P2O5*

0,3 %

Phosphorus pentoxide is phosphorus oxide long known by the formula P2O5, but the correct crude formula is P4O10. There are more than fifty pearlgleaming pearl pigments with shades and sparkles, each just as magnificent as the next. Howard R. Linton is the inventor of synthetic pearl pigments filed in US Patents 3,087,828 of April 1963. Pearl pigments are pigments made by coating a metal oxide on a laminar substrate. The resulting pigment is semi-transparent, and has some unique optical properties. This coating process is generally a sol-gel process, which means that salt solutions are used for the precipitation.

PEARLESCENT PIGMENTS

Muscovite also called white Mica

They can be divided into two categories: 1.Natural substrates: mica, kaolin or phlogopite 2. Synthetic substrates: alumina, silica, borosilicate or synthetic mica. Iriodin® pearl glow pearl pigments are composed of laminated mica with 45 to 66% silicon dioxide SiO2 (Quartz) which is the main constituent of sand and 19 to 29% titanium dioxide TiO2 (rutile) , 15 to 25% iron oxide Fe2O3 and 0 to 1% tin oxide SnO2.


PEARLESCENT PIGMENTS - PEARL GLEAMS - GLITTERING

237

The particle size of mica pigments varies in the order of 10 to 60 µm depending on the supplier. Their densities vary from 28 to 32 g / 100 ml. Oil absorption 55-65 g per 100 grams. They are insoluble in water. Mica refractive index: 1.6 Heat stability up to 800 ° C pH varying from 4 to 9

PEARL MICA PIGMENT

Here is a mixture that gives a beautiful white shiny glitter with pearlescent effects : • PW 20 77019 = Very fine mica 25%. • + PW 15 77861 = Tin white 25%. • + PW 6 77891 = Titanium white 50%.

PIGMENTS GLITTER

It is the last category of special effect pigments to have been invented. Diffracting (interference) pigments are produced by diffraction technology. These pigments are made by vacuum deposition on surfaces with special patterns. They were originally invented for cosmetics. There is a whole range of them. See and Supplier N°5's website where you will find examples of this type of pigments. http://bit.ly/Pigments-scintillants http://www.impactcolorsinc.com/Diamond-Silicates

Magic Indian Pearl Pigment

Royal gold glittering pigment 100 µm

Mica Pink Paliocrom® BASF

Pearl Luster Magic Turquoise MIRA®

Pearl Luster Magic Colibri gold star

Potassium (K) and aluminum (Al) silicate + Tin oxide + organic pigment. The pink Paliocrom® is coated with mica with reduced titanium dioxide TiO2, the pigment has a cool pink undertone with blue light reflections. These combinations of organic and inorganic pigments provide additional benefits for new hues and effects. Paliocrom® pigments are dyes for industrial use based on micaceous metal oxides. They are heat resistant and are characterized by good resistance to atmospheric agents. Link Pigments, resins, crosslinkers and additives BASF http://bit.ly/Paliocrom-Pigments


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FLUORESCENT & LUMINESCENT PIGMENTS

In 1852, Sir George Gabriel Stokes, an Irish mathematician and physicist, gave the name fluorescence (of fluorite) to the phenomenon of luminescence that certain materials produce when subjected to ultraviolet rays, thus emitting light of greater wavelength. , included in the visible spectrum. Ultraviolet light or "black light" is not or hardly visible by the human eye, because it is located beyond the zone of violet, it is endowed with a greater energy, but d At a lower wavelength, less than 4000 angstroms, one angstrom is equivalent to 0.1 nanometers or 1e-7 of a millimeter. Ultraviolet light excites the electrons that are around the nucleus of the atom. When the excited electrons return to their original orbit, they emit an amount of light energy that is very brightly colored. This light scattering can remain despite the stopping of the stimulation, in this case we speak of "phosphorescence". Most minerals react to long waves, some to short waves; others to both.

A B

Fluorite (15x8cm) BY Didier Descouens via Wikipedia A : Lumière du jour - B : Lumière Ultraviolette

There are some fluorescent inorganic pigments made up of host crystals, oxides or metal sulfides doped with other metals, such as Europium-doped Strontium aluminate: SrAl2O4: Eu2 + while organic dyes are made up of l 'Oxinaphthaldazine or disazomethine which can be prepared for example by condensation of one molecule of an aromatic diamine with two molecules of 2-hydroxy-3-carboxy-1-naphthaldehyde, or a substituted derivative thereof, but it there are also yellow green uranine dyes C20H10Na2O5 soluble in water, used as a leak detector. Rhodamine B (C28H31ClN2O3) a bright fluorescent pink PV1 45170: 2 and PV1: 2 45170: 4. Quinophthalone pigments, isoindolinone groups, azomethine pigments PY 101 48052 known since the end of the 19th century (PO59 12075, PO65 48528, PY129 48042), can also constitute fluorescent pigments, just like certain azo pigments (orange and yellow) which fluoresce on exposure to radiation, leading to an increase in spectral and light response [76]. The pigments are mixed with a transparent polymer, an amino resin of chemical description = Polycondensed triazine-toluene resin of sulfonamide-paraformaldehyde in a synthetic coloring material.

Binding fluorescent pigments in this resin reduces damaging influences due to temperature, water and U.V. Fluorescence can be obtained both by daylight and artificial light sources. Extremely intensive fluorescence, eg. for the special effects, perhaps obtained, with a contribution of "black lights" which emit UV rays. Pigments transform short waves of light present in wavelengths (color) which they also reflect. [77] Specific weight: 1.4 kg / liter Stability temperature: + 140 ° C Decomposition temperature: 300 ° C Most fluorescent pigments do not contain metal ions except zinc. Blue and green pigments contain copper. Organic fluorescent pigments do not contain inorganic phosphorus, radioactive substances, components that damage the ozone layer. They can be used for making toys and for finger paints. The binders with which these pigments are mixed should be as transparent as possible. The addition of standard fillers and pigments greatly reduces fluorescence. Fluorescent pigments should be mixed only with bold color tints - for example, yellow and green, or two different red tints, but never with their complement. Fluorescent pigments are moderately resistant to light, they can be used with oil, acrylic, tempera, and all water-based paints [43]. Works of art made with fluorescent paints must be protected from light if the lifespan of the fluorescence is to be extended; for example with a varnish with Tinuvin 292 and 900.

Range of fluorescent pigments Kolortek.com


239

FLUORESCENT & LUMINESCENT PIGMENTS Fluorescence is not uncommon in nature, many organic and inorganic species fluoresce in some way, such as most soils containing fluorescent humus, as well as many bacteria. Fluorescence is common in minerals like Willemmite and Fluorite.

Rhodamine B

Willemmite under U.V lamp .Photo : Jim Simpson http://www.tigerowner.com/Hall_of_Fame.htm

Fluorescent pigments showing their effect in "daylight" are an American invention dating from 1930, created by Bob and Joe Switzer, they experimented in order to combine certain dyes and certain resins which would produce paints much brighter than normal, they "radiated" under UV light or black light. Fluorescent pigments are dye solutions on a solid support of polar resins. Fluorescence is a process of photoluminescence by which short wavelength light, whether in the ultraviolet or the visible electromagnetic spectrum, is absorbed and re-emitted at longer wavelengths. Fluorescent dyes in their undissolved state are not fluorescent, only once they are dissolved on a thermoplastic or thermosetting resin support (they are ground into a fine powder) then they become fluorescent pigments. Daylight fluorescent pigments convert energy from the ultraviolet spectrum and convert them to longer wavelengths visible to the Fluorescéine human eye. An object painted with a fluorescent pigment specific to daylight reflects its visible color and absorbs and transforms the UV wavelengths of that color.

This creates a visual effect of "super shine", comparatively the shade looks brighter than a standard color. These products are known as Fluorescent DayGlo. Only a few fluorescent dyes are commercially available, and can be made into pigments. Some of these most important dyes are based on Rhodamine B (there is a whole range of them), which was invented in 1877, and on coumarin. Advances in the development of fluorophores include various categories of fluorescent dyes : • rhodamines which are fluorescent organic heterotricyclic compounds based on fluorone • fluorescein C20H10Na2O5 or 3H-xanthene3-one • 4-amino-1,8-naphthalimide used to make sensors, sensors or markers. • BODIPYs derived from 4,4-difluoro-4-bora-3a, 4a-diaza-s-indacene • pyrene which is a chemical compound of Formula C16H10 from the family of polycyclic aromatic hydrocarbons (PAHs) • porphyrin which serves as fluorophores to label biological reagents. We can also mention a Diamidino yellow pigment (DY), a True Blue (TB), a Granular Blue (GB), an Evans Blue and a Nuclear Yellow, as well as a Fast Blue: CAS No. 73819-41-7 classified in Color Index under the reference FB 2: 1 Fluorescent Blue 2: 1: Excitation wavelength: 365nm Emission wavelength: 420nm. Decomposition temperature> 300 ° C Specific weight ~ 1.4 g / ml Average oil absorption 56% There is also a whole range of UV light pigments, referred to as "Basic" "Acid" or "Solvent", these pigments require activation via an alcohol or another activator.


240

FLUORESCENT & LUMINESCENT PIGMENTS The range of fluorescent pigments from yellow to magenta is obtained by combining dyes at different ratios so green is obtained by mixing yellow and phthalocyanine green on the resin support. Blue is a combination of phthalocyanine blue and coumarinbased benzopyranone optical brighteners.

Rhodamine

The original techniques used to make fluorescent pigments have varied over the years: • In the beginning, these pigments were made by a mass polycondensation reaction of melamine, formaldehyde and toluene sulfonamide. The resulting thermoplastic or thermosetting products were suitable for various applications in molar ratios of polymer raw materials. • Another method developed in the 1970s to make fluorescent pigments is assimilated to the first, it uses suspension polymerization. This technique offers pigments which combine excellent inertia and very luminous pigments. An important component in the manufacture of fluorescent pigments is the basis of the pigments used, as it should be remembered that these are solid solutions of dyes that only fluoresce when dissolved.

The stability of fluorescent pigments is 4 on a scale of 8, so it will be necessary to protect the paints with an anti UV varnish or an anti UV glass, however there is a risk that they will reduce the luminous effect of the paints. The ratio of fluorescent paints requires a high pigment rate compared to the binder, you have to find the right balance, because this will give a matte, nonshiny film. For best applications, you should consider that due to transparency, the shade of the medium or background should be bright, white is best. If necessary, an opaque white preprint should be applied to dark substrates or backgrounds. Pigments and therefore fluorescent paints and inks often show a tendency to bleed, so care should be taken to choose the correct shade for the overprint.

Mixing fluorescent pigments

Rhodamine

Changing the shades of fluorescent pigments should only be done with transparent pigments. Opaque tints "undermine" the fluorescence effect and significantly reduce gloss. One of the tips is to mix paints with conventional non-fluorescent lightfast pigments, so normal paint will last if the fluorescent paint ever deteriorates or disappears. Unlike conventional pigments, fluorescent pigments not only converge visible UV rays but also UV light with respect to their intrinsic color, therefore these paints have a double effect since we can also see them under UV light.


FLUORESCENT & LUMINESCENT PIGMENTS Common organic and inorganic pigments do not show this property and are gray under UV light, under black light. Due to these properties, fluorescent paints and inks can be used as "black light effect paints", e.g. to bring out elements in order to place them in the foreground whatever the perspective or in dark environments. The use of coarse screen fabrics allows the application of coats of paint thick enough to obtain the best possible light output and long fluorescence lifecycles. Fluorescent pigments can be mixed with many binder systems and are therefore suitable for almost all types of substrates. To obtain a glossy paint film, it will be necessary to make an overprint, that is to say to apply successive thick layers. The trick is to apply two, or even 3, thick layers on top of each other, so the effect will be longer (like with natural dyes!). The thicker the paint layer, the better the hold, since the binder that coats the pigment will also act as a barrier and protection against the sun's rays. It would be wise to add a little Tinuvin 292 and PVB or Special Gum Globalprene 1650 to the paint paste. Personally I use either a Polyurethane binder or a natural / synthetic resinous paint with dammar resin and Plexigum PG 611, but it is also possible to use a binder made of gum or natural glue, such as gum arabic or tragacanth, but also all binders based on cellulose ether such as Tylose, Klucel, Methocel, Benecel, etc. ... PolyVinylButyral or Laropal type binders are completely transparent, so they are perfect. Fluorescent pigments are not the most widely used

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in architecture or automobiles due to their inherently low resistance to light and the low resistance to dyeing of these materials. They are mostly used for signage, so if you decide to use them you will need to take all of these parameters into consideration. However, there are challenges painters can face when handling fluorescent dyes, as they are polymeric in nature, unlike organic and inorganic pigments, therefore they do not tolerate high grinding. In some cases, the polymer heats up and melts, causing unnecessarily large clumps. In addition, many fluorescent pigments are not resistant to highly polar solvents and the dyes used can migrate out of the paint. Personally I mix the fluorescent pigment with the binder in a bottle without grinding with a wheel, then I let the binder adsorb. This is possible because commercial fluorescent pigments are very fine. Further, as mentioned, fluorescent pigments are inherently poor in lightfastness. The best way to prolong the life of a fluorescent paint is to tint it with high amounts of fluorescent pigments, with a film as thick as possible, then cover with a varnish containing a UV absorber as clear and transparent as possible, the addition of synthetic resin is ideal.

improvements

Adding UV absorbers to the paint system has not proven to be a real improvement or protection over the long term, it is ultimately not a very effective way to improve the performance of fluorescent paints. . Here at the bottom of the page 2 references of very luminous fluorescent pigments that you might encounter in commercial tubes or elsewhere in pigmentary form.

fluorescent pigments "daylight" blue, white, red, yellow, which can be ground, but personally I only do a simple mixture with a hard brush, either with a natural binder (albumin or gum from tree) or synthetic (Laropal or Plexigum) or with an aqueous acrylic binder such as Primal © which is completely transparent once dry.


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FLUORESCENT PIGMENTS - ACIDS AND SOLVENTS DYES Reference

TOXICITY Normally, most fluorescent pigments do not contain heavy metals such as cadmium, lead, mercury and hexavalant chromium or chromium VI (this is the sixth oxidation state of chromium). In addition, many fluorescent products have been tested for skin irritation and acute toxicity. The most important pigments were tested and classified as being essentially non-irritant and essentially non-toxic with a Lethal Dose 50 in rats orally of> 5000 mg / kg.

Table opposite some acid dyes and solvents. Often the reference of the solvent is its Color index. On https://bestchem.hu/bestchem/en/chemicals/ dyes-pigments/list you will find many dyes Acids and solvents.

Colour Index

CAS Number

42080 42645 42650 50415 18690 SBk34 SBr43

3486-30-4 5863-46-7 4129-84-4 11099-03-9 5601-29-6 32517-36-5 61116-28-7 61711-30-6

dye

Acid Violet 7 Acid Blue 15 Acid Violet 17 Solvent Black 5 Solvent Yellow 21 Solvent Black 34 Solvent Brown 43 Solvent Blue 48 Orasol® Black X51 Orasol® Black X55 Solvent Orange 58 Solvent Yellow 82 Solvent Yellow 90 Solvent Orange 99 Solvent Red 119 Solvent Red 127

orasol blue 2GLN

Solvent Black 27 Solvent Black 29

12237-22-8 61901-87-9

Solvent orange RL

71775-93-4

SY 82

12227-67-7 61116-26-5 110342-29-5 12237-27-3 61969-48-0

SY 90 SO 99

SR 119 SR127

FB SERIES DAYLIGHT FLUORESCENT PIGMENTS The fluorescent pigments of the FB series referenced Q / RWH107-2011 have brilliant hues, intense fluorescence and good dispersibility. The complete range has 22 very stable pigments. They are mainly used in color pastes, water-based paints, but also based on aliphatic hydrocarbon solvents and aromatic hydrocarbons for their increased resistance to solvents. Fluidity ≥ 30.0 mm; Coloring power ≥ 95%; Oil absorption ≤ 55%; Average particle size ≤ 6 µm; Particle density 0.6 g / cm3; ref. http://www.wanlongchemical.com/EnProduct. asp?ClassID=3

FT SERIES FLUORESCENT PIGMENTS

FT series fluorescent pigments are very high performance pigments, possessing vivid hues, excellent solvent resistance, especially in high molecular weight polar solvents such as ketones and esters. FT series fluorescent pigments can find extensive applications in paper printing inks, screen printing inks, lacquers and other paints. Coloring power = 100 ± 5%; Oil absorption ≤ 45%; Average particle size ≤ 6um; Density 1.34 g / cm3; Heat resistance up to 250 ° C Ref. http://www.wanlongchemical.com/EnProduct. asp?ClassID=25

Albumin and cherry gum with fluorescent yellow pigment


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PHOSPHORESCENT PIGMENTS Phosphorescent Pigments show virtually no tint in daylight, but they glow and glow in the dark by selective absorption of light, emitting wavelength after 1 ms. There are very few phosphorescent pigments, however, there is one blue, one red and two green [44]. Data sheet of a Phosphorescent Green [45] of composition: ZnS, Cu, Co - mixture of zinc, copper and cobalt sulphide. Modern compositions are strontium aluminate (SrAl2O4) doped with europium, which is much less toxic. A synthetic resin such as Paraloid® B 72 dissolved in ethyl acetate can be used as a binder and varnish. See at synthetic resins. Solutions of organic blue and white phosphorescent treatments hosted by a polysiloxane derivative used in polymeric light-emitting diodes have been formulated recently. New phosphorescent yellow iridium complexes containing a carbazole-oxadiazole unit [80] used in polymeric light-emitting diodes, polymethacrylates and polystyrenes with carbazoleoxadiazole side chains exhibit good thermal stability, spectroscopic properties and electrochemicals suggest their suitability as hosts of transformable solutions for green phosphorus. [78]

Green phosphorescent paint

1

Bases and acids destroy these pigments, just like daylight. Phosphorescent inorganic pigments can be made with alkaline tungsten salts.

Others luminophors 1. 2. 3. 4. 5. 6. 7. 8.

Alkaline halogen Alkaline earth oxide Alkaline earth sulphide Barium oxide doped with Mn, Ce, Sn, Cu, Ag Zinc phosphide, cadmium phosphide Gallium sulphide and Gallium phosphide Zinc sulphide Cadmium selenide

Phosphorescent organic pigments can be made from pure organic phosphorus with carbazoles as well as other fluorescent organic substances embedded in crystalline material. [79] Research continues to discover new solutions and pigments to the satisfaction of painters [80] [94].

Phosphorescent pigments ZnS powder and SrAl powder by FK1954

2

Glow in the dark pigments By FK1954

3

Glow in the dark pigments 4 min later by FK1954


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ORGANIC PIGMENTS AND MODERN SYNTHETIC DYES Their respective families will be studied in detail under 3 sections Organic pigments or rather as one should say: dyes, are natural materials, plant, animal or extracted from petroleum and modern chemistry. They are called synthetic organic dye. There are over 8,000 pure and unique dyes. The primary quality of a dye is that it is soluble in the binders with which it is mixed, unlike inorganic pigments. Colorants are readily used in inks and dyes for their high solubility. The dyes are dissociated in the order of 1 µm (micrometer), that is to say they are very fine, which is why they are used in dyeing and in the manufacture of inks. However, the resistance to light and abrasion of dyes does not exceed that of inorganic pigments, although enormous progress has been made in this area. Humans have used vegetable dyes for painting their bodies since prehistoric times, at least as long as they use ocher in its natural state.

Madder roots

VEGETAL

1. Pigments lacquered from animal dyes. 2. Pigments lacquered from vegetable dyes 3. Modern synthetic dyes. The discovery of mauveine by the young English chemist William Henry Perkins heralds a revolution in the dye industry. This discovery was of great importance to the textile and chemical industries, when he produced mauvein on March 23, 1856, the first synthetic dye was born. Until then, commercial dyes used to dye fabrics were very expensive natural products. In addition, during the Victorian era, fabrics faded in the wash and they faded in the sun. For centuries, purple dye was especially the attribute of the wealthy and royalty, so over 10,000 murex (the mollusk, from which the mucus was used to obtain the dye) were needed to dye a single Roman toga. [27 ].

Structure of Heliogen Green

SYNTHETIC

Sepia Officinalis

ANIMAL


245

PIGMENTS OF THE ANIMAL KINGDOM

Genuine Indian Yellow

Sepia

Sepia

Sepia

Cochineal

Cochineal + Madder

Cochineal lacquer

Cochineal red

Carmin naccara

Cochineal from Mexico

Ivory black

Ivory black

Murex

Purple from Cochineal

Damour oyster white

Pearl White Gofun Shirayuki


246

PIGMENTS OF THE ANIMAL KINGDOM

Carmine of Cochineal

Blood of Saint John, crimson, vermeil, carmine, carmine nacarat, carmine lacquer. Color Index natural red NR 4 75470 and food coloring E120 [126] which is used to color tarama, in confectionery, lipstick, etc. ... Currently in 2016, there really is no economical process to create synthetic carmine. The substance of carmine red is 7-R-D-glucopyranosyl-9,10-dihydro-3,5,6,8-tetrahydroxy1-methyl-9,10-dioxo-2-anthracenecarboxylic acid of Chemical Formula C22H20O13. Refractive index ~ 3.0 and Oil absorption ~ 70%. Powdered lacquer is obtained by the aqueous extraction of crushed cochineals (Coccus Cacti) (which contain about 10% of a red dye), followed by evaporation to dryness which is then fixed on a load by precipitation with aluminum and calcium salts. Carmine is soluble in alkaline water and acidic solutions. Staining from red to orange-red from pH 3 to 7, above pH 8, it gives purple-red tints. Concentration of the lacquer: 65% carminic acid. CARMINE MINERAL ANALYSIS Arsenic

3 ppm

Lead

10 ppm

Copper

25 ppm

Zinc

25 ppm

Ashes 8% Cf. [28] The word carmine may have come from the crossing of the Arabic qirmiz "cochineal" and the Latin "minium", vermilion, because in medieval Latin carminium is not attested. The French word carmin would be a derivative in -in of the old French "carme", the latter borrowed from Spanish. "carmez" from Hispano-Arabic qármaz from classical Arabic qirmiz: "cochineal". The cochineal [29] which provides a dye based on carminic acid has been overtaken by aniline dyes since 1880, however it is still available from most pigment suppliers. The cochineal comes from Mexico originally (since the discovery of North America), it is the shell of the dried insects of the female Coccus Cacti because it lives on cacti of the Opuntia coccinellifera, Nopalea type cochenellifera and Opuntia Ficus-indica which is derived from a calcium salt of carmine acid from the group of anthraquinone dyes. Currently, Peru, Bolivia, Chile and the Canary Islands are the main suppliers of scale insects [30]. To make a kilogram of cochineal red pigment, approximately 140,000 females are needed, in light of this precision, we understand its prohibitive price (380.80 € / kg), beware of falsifications, the powder must be of the same purity of tone than in the photos opposite. Carmine has been used in painting since the 16th century.

It is light-stable if well laquered with alumine, although nowadays it is not lightfast, this is no longer a problem with anti-U.V varnishes which filter ultraviolet rays (see Tinuvin® 900 and 292 varnishes). Carmine is very beautiful glazed with oil, moreover the great masters of the past placed it on a bed of cinnabar to retain all its sound and this in order to make these two capricious pigments used alone more stable. Cochineal carmine is not siccative, so it must be crushed with drying oil, moreover it requires almost 70% oil and does not withstand tubing, it sets very quickly. Its coloring and covering power is exceptional. I use it in illuminating, tüschlein, coloring juices as well as for oil glazes. It is a beautiful and irreplaceable lacquer pigment on the painter's palette. [31]

dried mealybugs, Grana

Cochineal ground in water

Red Cochineal Pigment without Tin

Cochineal Purple


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PIGMENTS OF THE ANIMAL KINGDOM The white from oyster shells and Gofun Shirayuki white

Gofun Shirayuki pearl white Japanese pearl is made with oyster shells which after processing give an aragonite shape. White is composed of hydrated calcium carbonate CaCO3 between 95 and 98% and humidity H2O between 2 and 5%. The shells are gathered in a large pile at the seaside of the city of Kyoto in Japan, where they begin to rot quickly, given the hot and humid climate there. Organic matter is left to decompose for 5 to 10 years. Starting from the finest shells, we obtain white flakes with a lamellar texture which are sorted then crushed and levigated to remove impurities to produce the most important white in the history of Japanese art.

It's a filler or a white, a magnificent pigment, neither too bluish nor too yellowish. It is incredibly pure. Its resistance to light is excellent. Based on its low refractive index of around 1.7, it is transparent in oil. It is compatible with all aqueous techniques such as Acrylic, Tempera, Fresco. You can make white with finely crushed eggshells and then purified by levigation; it has the same characteristics as pearly white, it is a very pure calcium carbonate. Genuine pearl white Gofun Shirayuki pearls are imported from Japan from the latest manufacturer to date [32]. Damour's oyster white in trochisques

The Authentic Sepia

Color Index Natural Brown NBr 9 75500. It is a coloring matter that is drawn from the ink bag of cuttlefish, a species of marine molluscs (similar to squid), Sepia officinalis, of the Sepiidae family. See [33].

Pearl white pearl Gofun Shirayuki

The "Gofun" has been known in Japan since at least the 8th century and was used on wood carvings (Moran 1960). It was noted in 1439 at the Hokanji Temple of Yasaka and on paintings of Karnak in Egypt. It was also used as a white for make-up. Gofun Shirayuki pearl white pearl was used in Japan from the 15th to 16th centuries in Japan to replace lead white. [134] the crushed white of the shells can be calcined with sulfur flower (a powdery variety of natural sulfur or sublimated after refining) to produce luminous paints. It is used in particular as an undercoat for gilding. It is mixed with a skin glue solution and applied to wooden panels, then glazed with the flat of a stainless steel knife to give it an Ivorian luster. It is one of the best whites for precious coatings, thanks to its special softness and silky texture. It can also be ground with water for use in the gouache technique or any other aqueous technique.

Sepia officinalis By Hans Hillewaert via Wikimedia

The cuttlefish is found in the coastal waters of temperate and warm seas, which is why it is also called "Adriatic cuttlefish". We must collect the coloring liquid as soon as we have caught the cuttlefish. The liquid is left to dry in the sun to allow wet material to evaporate, then molded or left as a powder. The coloring principle consists of a biological macromolecule, a protein similar to melanins [34].


248

PIGMENTS OF THE ANIMAL KINGDOM

These brown pigments which color the skin, eyes and hair in humans and also the feathers of birds. It is important to note that melanin is a free radical polymer exhibiting a highly conjugated structure which allows the transformation of UV radiation towards heat. Sepia melanin is a salt composed of Fe3 +, Ca2 +, Mg2 +, K + and Na +, with different qualities of polymer chains, the length of which depends on age, sex, season, etc. ... The melanin of sepia is more particularly a copolymer of eumelanin consisting of approximately 20% of 5,6– dihydroxyindole (DHI) units and 75% of 5,6 dihydroxyindole-2-acid units. carboxylic DHICA).

By using sepia or any other dye in a binder base rich in shellac, the ink is thereby made very glossy and very lightfast. The dry film is insoluble in water and may be diluted with water. Sepia is mixed with this saponified shellac using a base. Shellac makes the ink indelible after drying and perfectly fixed in the light. See Inks. Be sure to check the pH of the solutions before incorporating the pigment. With oil painting, if the works are not protected with an anti UV varnish, such as Tinuvin, the pigment degrades in less than 2 years. In the trade, in the form of paint, or ink, one does not find true sepia, it is replaced by synthetic substitutes. Check the Color Index which should be NBr9 for true sepia. Commercial paints sold under the reference "sepia" are in fact a subtle mixture of calcined sienna, iron oxide and carbon black, sometimes even indigo or organic yellows. The photos in this article were taken with real sepia. Sepia in full light

Sepia is not toxic. The Venetians make succulent pasta with cuttlefish. Sepia has been known and used since the 17th century, Seydelmann (1750-1829), a German painter, from Dresden, is known to have been the first to extract the dye from this mollusk with potassium hydroxide KOH, then filtration and precipitation with hydrochloric acid (E507) produced from the salt and sulfuric acid, thus allowing a higher concentration to be obtained. [35] SEPIA ANALYSIS [35] Compounds

Melanin Calcium carbonate Magnesium carbonate Alkali sulphates and chlorides Various compounds

%

78 10 7 2 0.8

Sepia is soluble in alkaline ammonia-type solutions, but is insoluble in water and solvents. It is best to use it, in aqueous binders, illuminating, washing, shellac, etc. ... Sepia gave its name to a wash technique that was very popular at the end of the 18th century. It has good coloring power, but low covering power, so it is very transparent. it has a very dark brown shade, almost black in all its strength, an irreplaceable warm brown. Sepia, like many organic materials, is sensitive to light, the color may turn red and fade after 2 years. Most inks use dyes, which makes them very thin and not very resistant to fading.

Note the power of the sepia tint


PIGMENTS OF THE ANIMAL KINGDOM Black Ivory also called Black Velvet

Many painters, and especially the Impressionists, regretted at the end of their career that they had not considered black as a color. Take a close look around you and you will see black and white everywhere, besides without these two colors the world would be very flat, no shadow, no relief, no 3D. To be honest, the painter in particular should take into account and appreciate all the colors. Ivory is a hard, white, opaque substance that is the main material in the teeth and tusks of animals such as elephants and mammoths. It is a precious material that has always served as adornment and sculpture, but those days are over, CITES obliges (Convention on International Trade in Endangered Species of Wild Fauna and Flora). Chemical description: real ivory carbon Chemical Formula: C Ca3 (PO4) 2 or C × CaPO4 Chemical composition: charred ivory, calcium phosphate containing carbon. Zero toxicity Refractive index: 2.5. Oil absorption: up to 50%.

TYPICAL COMPOSITION OF COMMERCIAL BONE BLACKS Carbon de 152 à 176 G Tricalcium phosphate Calcium carbonate

de 598 à 623 G de 40 à 76 G

Ivory black given its prohibitive price (460 € / kg), the draconian import regulations for ivory, the lack of raw materials as well as the increased use of plastics as a replacement for ivory made that he had gradually disappeared from the painter's palette. Ivory black is very lightfast and has good chemical stability, but it is considered the least permanent of the major black pigments. Ivory black is a semi-transparent pure blue black with a slight brownish undertone and possessing medium coloring power. Pure ivory black is a very dark pigment, bluish when mixed with white, it mixes well with any other pigments and creates a range of dull greens when mixed with yellow. This is the deepest of carbon blacks compared to lamp blacks (obtained by combustion). It has a very nice sound, straightforward, very useful in glazes, however care must be taken to grind it on marble with black oil, as it is a pigment that is not at all drying. See drying oil. Therefore, it should never be used as an undercoat because of this property, unless you wait 3 months before painting over it. Techniques in which ivory black can be used: oil, acrylic, tempera, water-based paint, fresco, etc.

According to Pliny the elder [37], ivory black was invented by Apelles (a famous painter of ancient Greece born in 352 BC). [38] True ivory black is obtained by calcining pieces of ivory in iron pots, sealed and then heated to approximately 800 ° C. On leaving the crucible, it contains impurities of phosphate and sometimes various salts. Higher varieties are obtained by washing to remove soluble salts. Genuine ivory black can be recognized by its characteristic shape under the microscope, by its typical carbon matrix. Ivory black and ordinary bone blacks (from beef, pork or any other ovid or bovid) have nothing in common, one being 98% carbon pure, the other ( bone) containing only 15 to 18% carbon. All ivory blacks in commercial tube paints or pigments sold under this name are common bone blacks, but have the same Color Index as ivory black. Authentic Ivory Black has not been produced since the end of WWII, except from very rare suppliers.

authentic ivory black

249


250

PIGMENTS OF THE ANIMAL KINGDOM

Guanine or White Silver or Pearl Iridescent

Color Index Natural White NW 1 75170 It is the only natural organic white with a Color Index. Molecular Formula: C5H5N5O IUPAC name: 2-amino-3, 7-dihydropurin-6-one Exact mass: 151.04941 g / mol Mono-isotopic mass: 151.049408 Da guanine is the oldest iridescent pigment. Guanine is a silvery powder of white tint made of natural pearl crystals with which we obtain films of paints with silvery reflections. When light strikes at interface boundaries, it is either reflected or absorbed. Complementary colors are visible due to interference (or iridescence) in the reflection or by transmission of light, so the viewing angle determines the color that is perceived. Guanine (2– amine-6 -​​ oxypurine) is one of the 4 main nitrogen bases found in nucleic acids (DNA and RNA Ribonucleic acid). Guanine is a derivative of purine [39] and hydrogenated bonds with thymine [40] and cytosine (cytosine is a nitrogenous base [41] and more exactly a pyrimidine base [42]). The nucleoside is called guanosine. Guanine is also the name of a white amorphous substance found in the scales of some fish, in the guano of seabirds, and in the liver and pancreas of some mammals. It can be used to make paint films shine. Guanine is similar to pearlescent pigments. It is transparent and has a very great fixity to light. Compatible techniques: Acrylic, Tempera, Water-based paints.

Blacks of Bones

Animal bone charcoal, deep black Color Index PBk 9 77267, the same as ivory black. It is made up of calcium phosphate and carbonate. Bone Black is made by heating fresh bones, if possible, to over 400 ° C, but not to exceed 800 ° C. During this process the organic compounds in the bone carbonize. The black carbon particles are deposited, they are very well distributed on a matrix of inorganic bone substances, more precisely calcium phosphate. Most organic substances break away from bone leaving small holes due to the spongy structure of this bone char; it is also called activated carbon. We divide it as much as possible, for the majority of bone black applications, we form with the very finely ground powder, small granules which will be pounded to make a paste. pH 9.0 to 11.0 Oil absorption ~ 60% approximately Particle size from 50 to 300 µm Bone blacks can be very anti-drying if there are traces of sulfide in the final pigment. Hiding power and variable coloring according to the carbon content. Bone blacks are compatible with all techniques such as Oil, Acrylic, Tempera, Aqueous paints, Fresco, etc. ... Black Animal By Honza Groh (Jagro) via Wikimedia

Mother-of-pearl powder <123 µm

Guanine from South America. It is a very fine, transparent white powder, a mixture of guanine and methylcellulose. Bone black


PIGMENTS OF THE ANIMAL KINGDOM

Nucella lapillus Nordische Purpurschnecke BY Manfred Heyde via Wikimedia Bone black

The Murex and the Purple of Tyr

Genuine Tyr Purple from which it originates also called Imperial Purple. Color Index Natural Violet NV 1 75800. This royal purple receives its name from the Purpura Lapillus and Murex Brandaris, but also from the Purpura Naemastoma a species of crustaceans that produces hypobrachial secretions of purple tint, depending on the species the color ranges from purple to red violet and red. Traditionally used to decorate the clothes of emperors and kings, but also to tint parchments, it takes about 10,000 individuals of this periwinkle (which weighs on average 16 g) to obtain 1 gram of dye, depending on the individual ; Murex Brandaris gives less coloring than Murex Trunculus. It is the most expensive organic dye in the history of mankind, so it was often adulterated with kermes (a kind of cochineal that lives on the kermes oak: Quercus coccifera or on the holm oak also says the oak. false holly: Quercus ilex) or orcanette (a red root of the genus Alkanna) mixed with pastel or indigo. This dye is very stable and resistant to alkalis, soaps and most acids. It is insoluble in the majority of organic solvents. For centuries, purple was the preserve of the wealthy and royalty, but since the invention of organic pigments and especially mauveine in 1856 by English chemist William Henry Perkins, purple has become an obsolete pigment. It is now hardly used except in the Enluminure or in restoring works of art, given its fabulous price of € 71 per gram, around € 60,000 per kilo, almost twice the price of gold.

Murex Brandaris & Purple

Purple from Tyr, authentic, extracted from murex trunculus [48]

251


252

NATURAL PIGMENTS OF PLANTS

Madder Root Powder

Lacquer by Geld and Bourdaine

Bladder Green

Red cabbage

Lamp black

Natural madder

Gamboge

Aleppo gall nuts

Blue Maya

Black vine

Sang-dragon

Stil Grain

Nettle

synthetic Alizarin PR83

Curcuma

Brazil wood

Indigo from Morocco

Indigo Japanese Polygonum

Bistre

Beech charcoal bistre


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NATURAL PIGMENTS OF PLANTS

MATERIALS NEEDED TO MAKE LACQUER PIGMENTS

1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11.

Plant extracts A pH meter and a solution to calibrate it Potassium alum Soda crystals (pH: 14) Ammonia (pH: 12) Borax (pH: 9.5) or wood ash (oak) Alumina sulphate for lacquering Iron Sulphate for making ink Calcium carbonate and kaolin as filler Camphor or sodium benzoate = preservative Baking soda or citric acid as neutralizing agents for pH

8 Iron Sulphate

3.Potassium alum

Saffron Nettle

Gomme-gutte Madder Root Powder

Red cabbage


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NATURAL PIGMENTS OF PLANTS

LA CONFECTION DES PIGMENTS LAQUÉS : LE LAQUAGE All kinds of substitutes are extracted from plants which must be treated in order to obtain a powder, called "lacquer pigment" which can be used in painting. First, the leaves or branches of the plants must be washed and then chopped in an electric mill. These ground vegetables are macerated in boiling water (15 min) and the solution is filtered several hours later. Finally, to constitute a powder, we must fix on a substrate (precipitate) the impalpable coloring principle contained in the water. This action is called lacquering. A lacquer is made up of 4 constituents: • A dye = leaves, flowers, fruits, roots, etc. • A substrate or a filler = calcium carbonate, sepiolit • One cation, one mordant = alum • A precipitant = soda crystals or wood ash Depending on the choice of components, different results and different colors are obtained, depending on whether the solution is alkaline or acidic. For example with red cabbage, we obtain up to 4 shades, purple, blue, green and pink, depending on whether we add, potash also called "washing powder" (ph = 13), soda (ph = 14) or pure lemon juice (ph = 2.59). The lacquering process generally proceeds as follows: 1. In a first tank, we dissolve in water alumina sulphate or alum Al2 (SO4) 3 and sodium carbonate: Na2CO3 or ammonia NH4OH to obtain an alumina gel. 2.In a second tank, a solution of dye in water is prepared, the contents of the 2 tanks are mixed and the lacquer is precipitated with soda crystals (pH = 14) or, failing that, wood ash . The lacquer is filtered, dried and then pulverized. From madder root for hairspray precipitation, alum is used at the rate of 20 grams per 100 grams of madder. For fresh plants, the weight of alum is divided by 4. The resulting hairspray is made from alizarin on an alumina substrate and the filler may be calcium carbonate. Pay attention to the pH, the index of hydrogen potential final, if you don't want to destroy your paper, your supports. So each plant has its own mode of operation, but in general the principle remains the same. An acid is a chemical that contains hydrogen = H. A base is a chemical that includes hydroxyl (OH). We neutralize the acidity or alkalinity of a solution, by adding its opposite, the bases are neutralized by the acids: we can use soda (sodium hydroxide) as a neutralizing base or citric acid as an adjuster. acidifying pH. An acid is neutralized by a base, the resulting reaction produces a salt and water (salt water). You can also use baking soda as a neutralizing base.

7.Sulfate d’Alumine

Choux rouge choux rouge

Natural madder roots

Nettle

The Flower of the Purple Black Hollyhock

The black mallow known as "Rosea Althaea" or "Rosea Alcea" of the Malvaceae family should not be confused with the wild mallow, the "Sylvestris Malva" which does not have a black brown flower, but rather blue red flowers. Rosea Althaea is originally from China, it arrived in Europe through Syria. It is a herbaceous plant that can grow for 6 years, but is more generally an annual flower. A single plant can produce up to a thousand flowers, which will give approximately 500g when dry. The picked flowers can be tanned without additional heat. Flowers dried in the shade contain more dye than when dried in the sun, however the flowers should be well protected from moisture.

My book No. 3 discusses in detail the preparation of each plant and vegetable usable in paint by the painter because this is an area so vast that demand an entire book. Mallow flowers


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In the 2000s, Germany was the most important supplier of mallow flowers. This mallow is currently cultivated mainly near Nuremberg in Germany, and then exported to France and England. Turkey is also an important center of the cultivation of this mallow. It is used to make very subtle black inks with metallic reflections, purplish, depending on the binder used.

Color chart of hollyhock at pH 2.9 on the left; at pH 5.8 in the middle and pH 5.4 on the right

The natural and synthetic madder

Colour Index Natural Red from NR 8 to NR 16 58205 /75330/75340/75410/75420 et Colour Index Pigment Red PR 83 58000, PR83:1 et PR83:3 et Pigment Red PR 112 12370 synthetic quinacridone. Chemical Formula of the synthetic madder C14H8O4. It is a natural blend of 6 dyes taken from the root of Madder Rubia tinctorum L. in the form of heteroside [46], including alizarin. Alizarin was synthesized in 1878 by German chemists Graebe and Libermann. The name of the active substance is 1,2-dihydroxyl anthraquinone. This dye must be fixed on an insoluble support to become a palpable pigment. Madder has been known since long before the Christian era, in India and Persia (Iran). Lacquering can be done on aluminum hydroxide, as well as iron, calcium and chromium to achieve a variety of shades. Nontoxic. Relative density according to the bite. Refractive index ~ 1.8 Oil absorption ~ 80%. Madder is sensitive in alkaline medium and cannot be used in the fresco technique. Good compatibility with pigments. high coloring power, but low covering power, it is transparent in oil, which is why it is mainly used as a glaze. It is preferable to use lacquer pigments to make thin layers of glazes and sfumati. Lacquer retards the desiccation of oils due to its phenolic nature. It has good light stability. In 1995, it was difficult to obtain it, it would seem to be produced again locally, in the south of France, thanks to the enthusiasm for the profession of the painter and the preservation of heritage. I was lucky a few years ago to find 1 kg from a supplier in Paris. If you have the opportunity to find rare or historical pigments, take advantage of it, because you don't know when the opportunity will arise.

Madder lacquer © Damour 2020

Red Pigment of Madder © 2020 David Damour

Ink madder © 2018 Damour


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LES PIGMENTS NATURELS DE PLANTES PROPERTIES OF REAL CAMBOGIA

Dark Madder-Alizarin Lacquer PR 83 58000:1

Acid index Ester index Saponification index Ash Humidity Density Refractive index

80,6 67,2 147,8 0,48% 3,7% 1.2 1.582-1.586

Gaude and Bourdaine Lacquer

Color Index Natural Yellow NY 2 75590 taken from a mixture of the bark or fruits of buckthorn, reseda luteola of the family Resedaceae and the fresh bark of young trunks and twigs of buckthorn, of the genus Frangula alnus of the Rhamnaceae family, such as grain stil. The coloring principle of Gaude is luteolin from Chemical Formula C15H10O6. The gaude precipitated alone with alum gives a light yellow lacquer pigment. It is a pigment which is not very stable to light, but which is compatible with all binders. With saponified shellac it can constitute a beautiful ink.

The Cambogia gum

on the left Gaude pigment and lacque of Buckthorn on the right

The gummi-gutta gum called Cambodge

Called Garcinia gummi-gutta L.; Garcinia cambogia Desr. ; Cambogia gummi-gutta L. ; Mangostana cambogia Gaertn ; Garcinia cambodia. Its name is derived from the province of Cambodia, where it was originally produced. Color Index Natural Yellow NY 24 The Cambogia gum is an organically sourced yellow gum resin obtained from the plants of the Garcinia Morella and Garcinia Hamburyi (rarer) types, both of which provide gummi-gutta. These shrubs of the botanical family "Clusiaceae" are native to Southeast Asia and grow in Thailand, Indochina and Cambodia for the hamburyi variety, in India, Ceylon and Thailand for the morella variety. The percentage of the resinous part is between 70 and 75%.

It was widely used in the 17th century, as a yellow oil glaze in which it is stable and solid, but for this it is necessary to dissolve it with alcohol, then mix it with Rubens gel or any other glazing medium., it can also be linked with saponified shellac. Otherwise with aqueous binders it is rather fleeting without an adequate binder to protect it. The composition of the gum-gutte owes its coloring principle to xanthones and hydroxanthones, compounds of gambogic acid, isogambogue acid, morellic acid, isomorellic acid, morelline, morellinole, isomorellinole, deoxymorellinole , dihydroisomorellin and neogambogic acid. The gum-gutte has a very beautiful yellow tint, mixed with madder and dragon's blood, it serves as golden lacquer; when mixed with azurite, it produces magnificent greens, remarkable for their intensity and depth. Turquet de Mayerne quotes it and gives recipes for gum-gut in combination with linseed oil. We use the gutte mainly in the Enluminure, in washes and in certain varnishes on supports protected from direct light.


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LES PIGMENTS NATURELS DE PLANTES It’s the only solid yellow I use in the Enluminure with the sophora, it’s beautiful. It can be replaced by the yellow Hansa PY 65. It is a toxic product, 7 grams is the lethal dose for humans. According to the EFSA compendium, the whole plant (Garcinia gummi-gutta) is known to have a negative impact on health due to the presence of HCA or hydroxycitric acid (30%). Gloves and a mask should be worn when handling powdered form [46].

These blacks of vegetable origin must be ground with water beforehand, then mixed with drying oil, although it is preferable to use them in the techniques of tempera, the Enluminure, tempera or in ink, etc. ... All vegetable blacks are anti-siccatives. These blacks are exceptionally beautiful. They are very covering and very coloring.

Cassel brown

Colour Index Natural Brown 8 77727 Cassel brown comes from the natural material of oxyhumolite which is the raw material for the manufacture of sodium and potassium salts of humic and fulvic acids. It is a dark brown to gray brown type of granular charcoal with a low degree of carbonization and a high content of humic acids as a component of humus. It occurs as a result of biochemical modifications of organic remains of dead plant substances which are extracted with an alkaline solution to make a dye which can be used preferably with aqueous paints. Humic acid between 15 and 30% min. with 65% water. pH ~ 9-10 Density ~ 1.30-1.40 g / m3 at 20 ° C Solubility in water ~ 369 g / l at 20 ° C Decomposition temperature> 100 ° C R 36/38: Irritating to eyes and skin.

Black vine in bright light

Lamp black also called candle black

Colour Index Pigment black PBk 7 77266 The black of the lamp is close to pure amorphous carbon. This black of plant origin is obtained by burning fir twigs or pine resin, which are burned in special oil lamps, allowing a black powder of remarkable finesse to be collected. This black has a grayish tinge, which makes it possible to make magnificent neutral grays; it is very stable and unaffected by light, acids and alkalis. Density ~ 1.77 and Index of refraction ~ 2.1 Oil absorption > 90 %

this Cassel brown is extracted from walnut

The Black Vine (1) and vegetable charcoal black (2) 1. Color Index Pigment black PBk 8 77268 It results from the carbonization in a vacuum of vine shoots harvested at the time of pruning, These flexible woody twigs are dried before cooking. No toxicity. 2. Color Index Pigment Black PBk 8 77268: 1 declared as a food additive E153 Vegetable charcoal. it is a micronized carbon black of plant origin obtained from the combustion of peat and birch, containing up to 95% carbon C. Certainly known since antiquity. Variable refractive index ~ 2.3. Oil absorption 60%. Full stability and compatibility. Often used to make pencils. Lamp black


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NATURAL PIGMENTS OF PLANTS Smoke Black from Camphor

Color Index Pigment black PBk 7 77266 Commonly called Combustion black. Refractive index ~ 1.9 to 2.25 depending on the origin. Oil absorption ~ 80 to 100% Always known. In general, the pigmentary material consists of carbon soiled with organic compounds. The best smoke blacks come from the combustion of camphor, supplied by various plants of the Lavrine family. Wood, charcoal, resins, oils, fats, etc. are consumed for the inferior varieties. .... During manufacture, an abundant release of gas is formed which ignites at the outlet of the devices, under large sheet metal bells where the black flakes are deposited, they are then collected and calcined. No toxicity. Excellent stability. Full compatibility with pigments and binders, however carbon black tends to float in aqueous binders, just add a wetting agent such as beef gall or Ethomeen C 25 to clump it. Excellent coloring and covering power, superior to bone, ivory, vine or peach black. It is a low-drying pigment in oils due to the presence of phenolic impurities from combustion.

This pigment in the form of pure and natural powder, coming from the combustion of camphor is unfortunately not found in Europe today. It is possible to make it by burning camphor.

Modern bladder green

Color Index Natural green NG 2 75440/75700/75695 It is an organic green made with berries of purgative buckthorn or ripe black buckthorn fixed with alumina sulphate and potash; different shades are obtained by varying the proportions of alum during the precipitation of the lacquer. Add a little indigo to brighten up the color. Originally, the berries were ground and soaked in water then added to a binder made of gum and left to dry in bladders where well precipitated with alum. Ripe buckthorn berries come from a shrub plant in the rhamnaceae family of temperate regions of the northern hemisphere, usually thorny and characterized by alternate petiolate leaves and small axillary flowers then mixed with yellow flowering reseda, used as a dye plant, available at the moment. Very beautiful oil glazes are made with this green, however, due to its medium stability, it is now advantageously replaced by a mixture of Indanthrene blue PB 15 and Isoindole yellow PY 109 or depending on the mixture of a big brand : PR 101: Synthetic red ocher + PY 150 : Synthetic Indian yellow + PG 36 : indanthrene green or phthalocyanine green + PBk 7 : Carbon black

Smoky black in aqueous paste. It's very convenient for quickly making paint by adding any binder.

European smoke black

Old tube of synthetic "Bladder Green" oil paint and natural ink on the right


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NATURAL PIGMENTS OF PLANTS The Grain Stil or Avignon Seeds

C.I Natural Yellow NY 13 75430/75640/75660/7567 0/75690/75695 from Chemical Formula C16H12O7 and C.I Natural Yellow N°14 75440 which gives yellow to brown tints. There are 4 shades of grain stil. Grain stils are made from the unripe berries of Rhamnus cathartica. Advantageously replaced by the gumgutte and the nut of gall.

A filler is added to it to give it body and then it is mixed with the desired binder, where it is dried to recover the lacquered pigment. The addition of acid makes the extract yellowish, the bases give an intense red color. the addition of tin salts gives a precipitation of carmine red and the iron sulphate a violet. It is used as a colorant in inks and in oleoresinous varnishes. It is very beautiful in the the Enluminure. See Enluminure color chart.

Rosette Pigment from my third book

Blood Dragon Yellow Grain Stil NY 14 75440 from unripe fruit

Brazil wood or Pernambuco wood

Color Index NR 24 75280 This bright, vibrant red natural coloring is extracted from a tree species in the Caesalpiniaceae family, Caesalpinis sappan Linn. which grows in India, but also C. brasiliensis from Brazil. The wood contains a dye, brasilin, a hydroxyanthraquinone with the formula C14H9O2 (OH)), which gives a deep red to brownish depending on the pH. It has been known and used since the 16th century as a high quality varnish for violins and various veneers. Brazil has chosen it as a national tree. Density ~ 1.1 kg / dcm³, twice that of oak. The dye mordanted with alum gives it good resistance to washing. A coloring matter is obtained by macerating pieces of Brazilian wood then boiling in distilled water, by manipulating the pH of the dye bath by adding wood ash or vinegar, we produce all kinds of colors of the brown to beef blood red.

Color Index natural red NR 31 75200 and 75210 This natural dye called "Resina Sanguis draconîs", resinous dark red is taken from the rattan fruit, the calamus draco, which grows in East Asia. He has been known since ancient times, Pliny the Elder quotes him. Its red resin consists mainly of an ether of benzoic acid and dracoresinotannol. Dragonblood tastes sweet, a little bit pungent. It melts at around 120 ° C. It dissolves very little in turpentine or ether, but it is very easily soluble in alcohol, benzene, chloroform, carbon disulphide, caustic soda, balms and partly in oils. It is used mixed with gum-gutte in lacquers and especially for gilding in order to achieve golden shades imitating the shade of gold.

Dragon Blood Powder

brazil wood

Dragonblood was widely used in the Middle Ages, as an undercoat for the preparation of the laying of gold or as a hot varnish. Since it is soluble in oil, it can therefore be dissolved and thus mixed with oily varnishes or Rubens gel, to give it a relative consistency to achieve magnificent glazes. Dragon Blood


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NATURAL PIGMENTS OF PLANTS Indigo, Indigotine and European Pastel

Color Index Pigment Natural Blue NB1 75780 and 75 790. For synthesized indigo PB 66 73000. Pigment of plant origin, insoluble in water and in alcohol, obtained by infusion and maceration of the leaves of Indigofera Tinctoria, a tropical plant of the fabaceae family, which grows in India, Asia and Africa. To prepare the dye, the freshly cut plants are soaked until they soften and then baked at 50 ° C for 1 hour. The precipitate resulting from the fermentation is then mixed with a strong base, for example ammonia or lime water, in order to make the indigo partially soluble, it is necessary to maintain a pH of 8 to 10.8 depending on the desired shade. The kettle bath is filtered and then pressed into a solid for use in water or dried and ground to a fine powder for use in oil paints. The coloring principle of indigofera Tinctoria contains a heteroside [46] of Formula C16H10N2O2 Indigo has been known and used in India for at least 4,000 years, in Europe since ancient times. Indigo is a blackish-blue organic dye that develops its shade of blue with white in paint. It was the only source of blue "dye" until the invention of synthetic dyes in the late 19th century. It is one of the oldest dyes used for dyeing textiles.

of Indian indigo, I find its hue to be bluer. In 2019, indigo is also produced by the bacterium E. coli by genetic engineering. Bayer succeeded in synthesizing indigotin (available in various shades) from 1883, then it underwent intense development around 1897. No toxicity, on the contrary, very good for health. Oil absorption : 30%. The additive E132, indigotine, is a blue dye with the Chemical Formula C16H8N2Na2O8S2. Indigo has good chemical stability, it is destroyed only by very strong oxidants. It is compatible with all binders and pigments. Good coloring and covering power. Personally, I reserve indigo for the Enluminure and ink, but it can be used in oil thanks to Rubens' medium.

A little history of indigo and blue jeans

Used for 4 millennia in the Middle East, indigo provides the "blue" of jeans. The word "jeans" comes from the French expression "blue of Genoa", literally the blue of Genoa. The fabric of the Jeans or "denim" originates independently from the two places, from the French city of Nîmes, from where the name "denim" owes its name and in India, where the pants in "denim"

7 pastel shades made from fresh leaves donated by Cecilia Aguirre.

For centuries it was used in many Asian countries, but also in Mesopotamia, Egypt, Greece, Peru and Africa. The Romans used indigo as a pigment for painting, for medicinal and cosmetic purposes. It was a luxury item imported from India via the Mediterranean by Arab merchants. The most typical source of indigo is European pastel, its quality is not at all inferior to that

material were worn by sailors , they were thus named like the overalls. At around the same time, "denim" pants were made near Turin, Italy during the Renaissance and were popularized in the 16th century. These pants were sold through the port of Genoa. The jeans are dyed a blue color with indigo dye.

Tone-on-tone egg white pastel color chart on paper : I extract this pastel from fresh leaves : thanks to Cecilia Aguirre for the leaves ;-)


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Origin PBK8 and the latter PBk7 as the inorganic result of burning Beech wood in the open air. Bistre consists of pulverized soot, collected on the chimney pipes after the calcination of beech, birch or poplar wood. It is composed of carbon, tar oil and sulfur. It is a hydrogen carbide that can contain between 78 and 82% carbon.

Persicaire indigo

Bistre PBk7 77266 raw I made it in a fireplace after burning beech, then I collected soot on the chimney hearth.

The soot is recovered, it is finely pulverized, it is sieved, it is washed in cold water then in boiling water with a solution of potash, to rid it of all soluble salts, thus obtaining a very fine powder that we mix with gummed water and that we can mold and dry. This produces a very dark aqueous ink of bistre ink with brownish reflections. It is mainly used in aqueous techniques. The quality bistres come from beech or birch soot. It is a warm yellow-brown material, which was used as a wash. Leonardo da Vinci gives a recipe for natural bistre. It is a solid pigment in wash, illuminate, and saponified shellac solution. In the trade, natural bistre (NBr11) is now replaced by a mixture of transparent iron oxide mixed with black. Charcoal density ~ 0.561 kg / liter Natural Indigo brought back from a trip to Morocco

About 14,000 tonnes of indigo are produced each year for this purpose, but it only takes a few grams of dye to dye pants.

Bistre or Beech Charcoal

Color Index Pigment Natural Brown NBr 11 and PBk 8 77268 as well as PBk7 77266 depending on the source and method of making the pigment. "Bistre" is a word dating from the 16th century. Bistre can be classified under 3 different Color Indexes, one as natural organic dye NBr11 comes from soot, a fine and organic material, recovered from the chimney flues which is treated then transformed into ink by means of potash (chloride of potassium), the other as Natural Organic Coal Pigment and Mineral

Bistre in the photo above after purification. It will be a very beautiful brown ink.


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Turmeric Root By Simon A. Eugster via Wikimedia

Beech charcoal bistre PBk8 77268

Beech charcoal bistre PBk8 77268

Colour Index Natural Yellow NY 3 75300 Chemical Formula : C21H20O6 Food coloring authorized in France : E100ii [126] Turmeric is the root of a plant in the scitaminea family, native to the East Indies. It owes its coloring principle to curcumin which is the main yellow-orange coloring part of the herbaceous plant of Curcuma Longa L. or Indian Saffron. It can be isolated by distillation with steam, but it can also be extracted by solvent and chemical extraction. Curcumin is obtained using a solvent by extracting turmerol, i.e. ground rhizomes of strains of turmeric longa L. The extract is purified by crystallization in order to obtain concentrated curcumin powder . The product is essentially composed of curcumin, that is to say of the coloring principle [bis - [hydroxy -4– methoxy -3 - phenyl] - 1,7– heptadiene-1, 6-dione-3, 5] and of its two demethoxy derivatives in varying proportions. It can also include small amounts of oils and resins naturally present in turmerol. Curcumin is also used in the form of aluminum lake, in which case the aluminum content is less than 30%. Only the following solvents can be used for its extraction: ethyl acetate, acetone, carbon dioxide, dichloromethane, n-butanol, methanol, ethanol, hexane and propanol -2 . Turmeric becomes unstable at pH 3, curcumin is more stable. Curcumin is listed E100 and E100i as a colorant in the Codex Alimentarius standard, it can be used alone or with other colorants, especially in food materials and in cosmetics. Turmeric is cultivated in Southeast Asia, more specifically in India. It is used in aqueous techniques by simply adding a binder such as albumin, gum arabic or methylcellulose binder. Curcumin develops a very powerful very bright yellow tint in aqueous binders, unfortunately fleeting in the sun.

Turmeric from India

Gallnuts and Oak Apple

Colour Index Natural Brown NBr 6 The gall nut is made from chebulinic acid which is extracted from the dried fruits of terminalia chebula (Myrobolan). Galls are tumor growths produced on the stems, leaves or fruits of certain plants as a result of bites from parasitic animals. Gall is a tumor produced by plants, but usually induced by the egg that is laid under the cuticle of a leaf or stem and that will develop there. Oak apple is a mutation of an oak leaf caused by chemicals injected by the larvae of certain types of gall wasps. They are so called because the gallbladder, which can measure up to 5 cm in diameter, but more generally 2 cm, looks like an apple. The gall nuts used in commerce and medicine are growths on Quercus infectoria, a small oak tree, native to Asia Minor and Persia, the result of the puncture of the bark of young twigs by the female gall wasp , the "cynips galle-tinctoria" [61], which lays its eggs indoors. The common oaks of this country are very affected by gall. Nuts sometimes occur on the leaves, where they form oak apples, sometimes on the shoots, where they do a lot of damage by deforming and preventing the growth of the tree. The young larva that hatches from the egg feeds on


NATURAL PIGMENTS OF PLANTS the tissue of the plant and secretes a special fluid in its mouth that stimulates the cells of the tissues to rapidly divide and develop abnormally leading to the formation of a vesicle. The best gall is collected in Turkey-Syria, mainly in Aleppo province, where it is harvested before the insects take flight.

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solid of white tint used as a reducing agent in photography and for ink, etc. They are not spherical, but extremely diverse and irregular in shape, large, gray, velvety, and reddish-brown in color. They contain about 70% gallotannic acid. The gallnuts of Mecca, Basra or Basrah (a town in the province of Chaldéc) are spherical in shape and surrounded around the center by a circle of horned protuberances.

Aleppo gall nut (1)

Good quality galls are hard and heavy, without perforations, dark bluish green or olive green (1), and appear as spherical balls, 12 to 20 mm in diameter. The main constituents of Aleppo gall nuts or Turkish galls are 50 to 70% gallotannic acid, 2 to 4% gallic acid, mucilage, sugar, resin and an insoluble matter, mainly lignin. If the nuts are harvested after the insects have escaped, the galls will be paler, brown in color, spongy and lighter, punctured with a small hole near the center. They are known commercially as white gall. They contain less gallotannic acid. When you break one of these gallnuts, it appears yellowish, brownish, or white on the inside, with a small cavity containing the remains of a wasp larva. Gallnuts do not have a strong smell, but an astringent flavor, and a slightly sweet aftertaste. The nuts of the pedunculate oak of the gall or oak apple are smooth, globose, brown, generally perforated and much less astringent than the Aleppo galls and contain only 15 to 20% gallotannic acid. They have lesser commercial value. The Chinese gall nuts produced by the bite of the species "Y Aphis chinensis" on the "Rhus semialata" are mainly used for the preparation of tannic and gallic acids, pyrogallol (benzene -1,2,3– triol ) a crystalline

Aleppo gall nuts in balls and crumbs

Galls are used commercially for the preparation of gallic acid and tannic acid and are widely used for tanning, dyeing, and in the manufacture of inks. [47] Gall nuts are mainly used by the painter to make inks and for tanning canvases. They must be reduced to a fine powder in order to mix them with the constituents, making it possible to make brown or black inks. See ink on next page

Oak apple By Bob Embleton via Wikipedia


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NATURAL PIGMENTS OF PLANTS tion of wine lees and tartar were performed on a large scale in parts of Germany, in the vicinity of Mainz and even in France. This is done in large cylindrical containers or in jars with an opening on the lid to allow the passage of smoke, acid and alkaline vapors which escape during the process. the operation is complete when there is no more smoke. The resulting material, a mixture of salt and a very attenuated carbonaceous part, is then washed several times with boiling water, then reduced to an appropriate degree of fineness and finally crushed with a wheel on the marble.

Galle walnut ink

Charcoal or Charcoal Black Blacks of Calcination Charcoal, Carbon Black, Antique Black

Colour Index Pigment Black PBk 6 77266 Chemical Formula C Carbon black is the name generally used for blacks that are made from the partial combustion or charring of oil, wood, plants or other organic material. Carbon blacks have been used as pigments since the domestication of fire. They are made with natural wood or plant materials, with a very limited air supply. The best qualities are prepared with vine shoots, fruit stones or small twigs which are partially burnt and then crushed. Most carbon blacks contain various minerals and tarry, hydrocarbon plant materials. In 1864, a process was developed in America for making a black more suitable for aqueous binders. It was widely used from 1884. The American process uses natural gas as a raw material, the black deposits are automatically collected using large scrapers. The resulting powder appears in grains more dissociated than the other blacks, allowing it to bind more intimately with the aqueous binders. The pigment is stable, very resistant to light and is not afraid of oxygen. In the 19th century recipes resulting from the calcina-

Charcoals

Charcoals of different shapes and sizes


NATURAL PIGMENTS OF PLANTS Manufacture of Charcoal Sticks

Twigs and twigs from almost all types of trees, many woody shrubs and woody vines can be used. Avoid twigs less than a year old, they usually produce a powdery charcoal black. The ideal growth is two years. Peg sticks and scrap wood are also good sources of materials. Almost any type of wood will lead to the build up of charcoal. (Avoid using treated wood due to the toxic fumes emitted during the roasting process). The Twigs should be at least 6-10mm in diameter, as the wood will shrink when it turns into charcoal. Cut branches to the desired length of 12 to 20 cm. Peel off and remove all bark from the wood branches. If the twigs have just been cut, allow them to dry for a few days before moving on to the next step. Wrap several dry sticks, tightly wrapped in aluminum foil so that air cannot get into the package. If air got into the bundle, it would reduce the sticks to ashes rather than charcoal. Should the aluminum come in contact with an open flame, a hole could burn through the foil and spoil the charcoal, so it is best to be safe to wrap a second layer of foil tightly around the foil. First bundle. (But don't overdo it, because each layer of paper reduces the amount of heat reaching the wood). Make a first experiment with 5 or 6 sticks per pack. If the group contains more sticks, higher heat and more roasting time will be needed to completely char everything into charcoal. Softwood species, such as pine and cedar, will require less roasting time than hardwood species (such as birch, ash, oak or walnut). Place the packages in the hearth of a fireplace or on a barbecue. It may take several hours (or overnight) for the sticks to char and then cool. Do not open the package until it has cooled down enough to be safe to handle. You have to experiment with charcoal firing several times before achieving an optimal result. Too much heat will melt the sheet. Insufficient heat will produce marks. You should obtain good results after a few experiments, all of the manipulations of which you have taken care to note in detail. Charcoal can also be made in an outdoor ceramic kiln. If you use a ceramic kiln, be careful of temperatures above 300°C. High temperatures cause rapid charring and are difficult to control. Used throughout history, carbon black is easy to prepare and has excellent hiding power. Because carbon absorbs light so well, it often looks dark in infrared imagery, revealing the charcoal sketch made under the oil paint. The charcoal blacks are all anti-drying in oil. To fix the charcoal lines, use 0.5% Klucel dissolved in a 9/1 ethanol (ethyl alcohol) / water mixture.

Peach black, matte and silky black comes from the calcination of peach stones.

Black from peach kernels

Cherry Black, more gray in tone, comes from the calcination of cherry stones.

Black from cherry pits

Grape Noir with a bluish tone comes from the calcination of grape seeds.

Black from Grape seed

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NATURAL PIGMENTS OF PLANTS The Maya Blue

Mayan blue is a blue pigment found in several Aztec archaeological sites (Mexico, Guatemala, Honduras, El Salvador). This pigment was used extensively by the Mayans and other Mesoamerican peoples from AD 300 to 1589. Around AD, to make frescoes, paintings on ceramics, paintings on wood, pottery and objects of worship, etc. .... The pigment is an organo-clay complex. What characterizes the pigment is its remarkable durability over time and its resistance to acids.

The shade of the pigment obtained depends on the quality of the indigo used. The shades obtained will be more or less light and range from a greyish blue to a greenish blue if synthetic indigo is used or natural indigo from Indigofera tinctoria or Mexican indigofera suffruticosa. Indigo is insoluble in water. It is soluble in acetone and sparingly soluble in ethanol. The blue dye is destroyed by nitric acid turning orange-red. Mayan blue can be recognized mainly by its color, but above all by its resistance to acids. Some researchers explain the resistance of the pigment by the complete desiccation of the water and the entry of indigo molecules into the channels of the fibrous attapulgite, which would have somehow protected the pigment from climatic stress. [114]

Maya blue fresco

Mayan blue was discovered around 1931 by H.E. Merwin on Mexican murals. In 1942, R.J Gettens named it "Mayan blue", thinking he had found an exclusively Mayan pigment. In 1946, murals were discovered in Bonampak, Mexico, which made it possible to study in more detail the pigment by X-ray diffraction, Attapulgite (palygorskite) was then recognized as an adjuvant or main charge of the blue compound.

Authentic Mayan Blue in a Matrix of Silica Crystals

In 1962, finally, indigo was recognized by infrared spectroscopy as a constituent of coloring matter. It only remained to determine the method of making the pigment. There are currently 5 methods to make it, however the most stable pigment is achieved by the traditional route, as follows : 1.It is macerated leaves of indigo tree of the natural species "Indigofera Tinctoria" in an aqueous liquid such as water with a clay with a fibrous structure such as attapulgite, ie 10% indigo for 90 % Attapulgite. 2. We filter to remove the leaves 3. The solution is left to oxygenate 4.We filter again to recover the pigment 5.The pigment is baked for 5 hours at 190 ° C. Thanks to this traditional method, a very resistant pigment is obtained. The best resistance to acids, as well as the shade closest to Mayan blue, is obtained with a 10% concentration of indigo cooked for 5 hours at 190°C.

6.35 cm indigo tile Photo By Evan Izer (Palladian) via Commons Wikimedia


METALLIC PIGMENTS The prohibitive cost of gold determined the development of metallic powders different from those found in nature, such as gold, silver and copper. Aluminum did not appear until the 19th century with the development of bauxite processes, aluminum oxide, which represents between 40 and 50% by weight, is extracted and then electrochemically reduced to produce aluminum. It then competes with silver for its reflective properties. Its development is linked to the development of the spray drying process (1860) which consists in the production of powder which propagates very strongly from a liquid by evaporation of a solvent. It was not until then that modern aluminum pigments appeared. Metallic pigments have a particular form which is the origin of their other names, in the form of flakes in English "lamellar pigments" or "flakes", said to be of lamellar forms. Their largest dimension varies from 0.5 to 600 µm. They are characterized by a form factor of between 1/10 and 1/600, which corresponds to the ratio between the thickness and the average diameter of the particles, that is to say a variable thickness, from 0.1 to 6 micrometers. The first metallic pigments, made around 1930 had an irregular shape of "corn flakes", the control of the grinding conditions currently makes it possible to control their structure in a completely controlled manner. Metallic effect pigments consist of flakes or flakes of aluminum (aluminum bronze), copper and cop-

Aluminum particles coated with gold 0.4 X 0.4 mm in full light

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per-zinc alloys ("gold bronzes"), zinc or other metals. Some of these metal flakes, especially aluminum platelets, can be coated with iron oxide by a chemical vapor deposition process. The metal flakes are fluidized in nitrogen gas at temperatures close to 450°C Then, reagents of iron, carbon (CO) 5 and oxygen O2 are injected into the fluidized bed. For a proper coating, these must be very diluted in an inert gas. Sometimes water vapor is added to reduce the electrostatic charge. The thickness of the coating is controlled by the reaction time. The side product is carbon monoxide, which is catalytically oxidized to CO2. The pigments resulting from this treatment have a metallic gold effect and a reddish and orange metallic effect. Metallic films are used in various ways. Coatings are formulations in which powdered or flaked metals are combined with a binder. However, metallic films used as paint can be used by various and varied means. Such films are both functional and decorative and therefore form a layer which changes the surface properties of the support with those of the applied metal. The coated product is a new material which has an outer layer resistant to corrosion by the metal provided, while the load-bearing characteristics are provided by the core of the material. A wide variety of metals are used, these include aluminum, cadmium, chromium, copper, gold, nickel, silver and zinc.

Aluminum particles coated with gold 0.4 X 0.4 mm


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METALLIC PIGMENTS The reflective properties of aluminum foils give paints a metallic appearance. After application, the structure of the particles dictates their direction in the film parallel to the support. A cooperation effect is implemented between all the glitter which reflects the light in the same direction. Fig opposite. There are two kinds of pigments: 1. non-peeling pigments which distribute after drying consistently throughout the thickness of the paint layer. fig opposite 2. The film-coating pigments which are placed on the extreme surface of the film formed. Fig opposite. The former can be used in the presence of colored pigments in order to obtain a metallic coloring by reflection and absorption, while the latter produce, by covering between the pigments, a very reflective effect which makes it ineffective (and therefore unnecessary). use of colored pigments. There is a new variety of metallic pigments, this new kind of pigment offers possibilities to achieve reflective surfaces, instead of using transparent mica as was the case before. These pigments consist of small rectangular aluminum flakes coated with an epoxy resin that protect them from oxidation. The manufacturing process for these pigments is bonding, that is, the adhesion of the pigments to the surface of the powder grains. This effect is achieved by a special thermal process where a stable resin-pigment interaction is established by heating the pigments above the softening temperature of the resin. This temperature rise causes, with stirring, the powder to cling to the surface of the pigment and its partial encapsulation. This process has only been able to develop thanks to progress and the development of knowledge in the field of powder formulation. However, this process turns out to be more expensive, because it must be specific in terms of treatment time and temperature, for each type of resin-pigment mixture, to be effective. The result is a sparkling, extremely shiny and moisture resistant surface. The most effective way to achieve color reflections is to add translucent organic pigments or concentrated pigments to metallic flakes. The flakes are available in 5 sizes from 0.1 x 0.1mm to 0.6 x 0.6mm and they are compatible with all binders. One of the optical properties of metallic paints is the appearance of a double effect characterized by high gloss in the direction close to the direction of reflection and darkening when moving away from this angle. This characteristic effect of reflective pigments is called the "flop effect" or "two-tone effect" and distinguishes them from ordinary pigments which only diffuse light in all directions with equal intensity.

Reflection of light by metallic pigments in a paint film

Non-film-coating or non-leafing solution

Disorganized pigments

leafing Solution or "creaming"


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METALLIC PIGMENTS Characteristics of metal flakes Material: aluminum foil Al => 90% Epoxy resin coating = 8% Particle size: from 100 to 600 microns Color: Gold, silver and aluminum Thickness: 19 microns (+ / - 10%) Cut: square Solvent resistance: yes Heat stability: 220 ° C

Stability of metallic pigments Stable for 15 min in Isopropanol from 2 to 5% Stable for 15 minutes in 70% isopropanol Stable for 3 months in demineralised water H2O

Bronze-tin-copper

Gold coated aluminum flakes 0,6 x 0,6 mm

Copper powder

Gold coated aluminum flakes 0.2 X 0.2 mm

Aluminum particles coated with silver 0.2 X 0.4 mm


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SYNTHETIC DYES AND PIGMENTS

Yellow Hansa PY 74

Yellow irgalit

Isoindoline yellow

Yellow Diarylide HR

irgazin Orange PY 110

Paliotol Orange PO59

Soudan 3G Yellow

Indian yellow imitation PY150

Hostaperm Red

Isoindole Orange

IRGAZIN Red

ORASOL®-Pink-478

Heliogen Green

Greenish irgazine yellow

Heliogen Blue

Indanthren Blue

Heliogen Blue more Greenish

Alizarin Purple

Hostaperm Red PR122

Perinone Orange


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SYNTHETIC DYES Dyes are substances which are soluble in the medium which they color unlike pigments. According to the Color Index, there are over 8,000 registered synthetic dyes. The dyes are listed, now on a website called Color Index, published by the Society of Dyers and Colourist and the American Association of Textile Chemists and Colorists, under two classification systems, a 5-digit number assigned according to the structure chemical, chromophore group (or Color Index number, CI number), a generic name which includes a use category number and a serial number accompanying the color. All industrial products of the same structure will bear this name, regardless of their trade name. With the exception of carbon blacks, organic pigments are more common today than inorganic pigments and minerals. The first writing referring to the use of natural dyes dates from 2600 BC. J-C. [49] It was not until 1856 that William Henry Perkins aged 18, in wanting to synthesize artificial quinine from allyltoluidine, accidentally discovered the first synthetic coloring matter, “mauve”, it is aniline, a basic colorant. The synthetic dyestuff industry had just been established. Synthetic dyes represent a relatively large group of organic chemical compounds found in virtually all spheres of daily life. The annual world production of dyes is estimated in 2000 at 700,000 tonnes. [92] In 1876, Otto Witt a German chemist noticed that colored substances all contained a characteristic group which he called "color-bearing" chromophore. He finds that by introducing a chromophore into a hydrocarbon (an uncolored compound) it becomes colored. It therefore becomes a chromogen, that is to say a more or less strongly colored molecule. Chromophores are groups with double bonds. The presence of a chromophore group (with a chromophoric double bond) is therefore responsible for the coloring of the molecule. Also if, the chromogen has a second group called auxochrome (increased) then it becomes a dye. Auxochromic groups allow the attachment of dyes to substrates. In fact, auxochrome has the property of increasing its coloration. The amine (- NH) and hydroxyl (- OH) groups are two examples of auxochromes. A dye is thus defined as a substance capable of dyeing a support in a lasting way. It has groupings which give it a hue. Synthetic (artificial) dyes are thus classified under headings and sub-headings : nitro derivatives, triphenylmethane derivatives, xanthenics, acridine derivatives, quinoline derivatives, anthraquinonics, indigoids, phthalocyanines, oxidation bases and azo, mono azo dyes, disazo and tri azo.

You will notice the complexity of the names of the dyes compared to the inorganic pigments.

Classification of dyes

Dyes of synthetic origin are complex molecules which can be anionic or cationic. They belong to a dozen different chemical families. Azo dyes are most commonly used due to the presence of the azo group (-N = N-) which gives these chemicals some resistance to light, acids, bases and oxygen, desired properties for the clothes. Note that more than 60% of world dye production is used by the textile industries. More than 53% of the azo dyes used are identified as being stable compounds, unfortunately not biodegradable.

Chromophoric groups NAME Azo Nitroso Carbonyl Vinyl Nitro Sulfide

STRUCTURE (-N=N-) (-NO ou –N-OH) (=C=O) (-C=C-) (-NO2 ou =NO-OH) (>C=S)

Auxochromic groupings Amino Methylamino Hydroxyle Dimethylamino Alkoxyle Electron donor groups

(-NH2) (-NHCH3) (-HO) (-N(CH3)2) (-OR)

Chemical classification of dyes Azo dyes

The dyes of this class are characterized by the presence within the molecule of an azo group (-N = N-) connecting two benzene rings. This dye category is currently the most widely used in application, accounting for more than 50% of world dyestuff production. Azo dyes are distributed as follows : basic, acidic, direct and reactive dyes, soluble in water as well as dispersed azo and nonionic mordants insoluble in water. It is estimated that 10 to 15% of the initial quantities are lost during the dyeing procedures and are discharged without prior treatment in the effluent! However, these carcinogenic organic compounds are refractory to the treatment processes usually implemented and are very resistant to biodegradation.


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SYNTHETIC DYES Triphenylmethane dyes

The dyes in this category are derived from triphenylmethane which is a hydrocarbon having three phenyl rings bonded to a central carbon. This basic structure is found in a large number of colored organic compounds. Triphenylmethane dyes and their heterocyclic derivatives are the oldest class of synthetic dyes. Currently they are much less important than azo and anthraquinone dyes, but they have retained a certain commercial value, because they allow to cover the entire range of shades. Triphenylmethanes are used extensively in the paper and textile industries to dye nylon, wool, silk and cotton.

Indigoids dyes

Indigo dyes get their name from indigo, from which they are derived. Thus, the selenium, sulfur and oxygen counterparts of indigo blue with colors ranging from orange to turquoise. Indigoid dyes are used as textile dyes, as additives in pharmaceuticals and in confectionery.

Xanthenes dyes

Xanthenes dyes are compounds which are derivatives of halogenated fluorescein. They are endowed with an intense fluorescence. Their properties as markers in maritime accidents or as flow tracers for underground rivers are well established. They are also used as food coloring, in the cosmetics, textile and printing industries.

Anthraquinone dyes

Anthraquinone dyes are the most important after azo dyes. Their general formula, derived from anthracene, shows that the chromophore is a quinone nucleus on which hydroxyl or amino groups can attach. They are used for coloring polyester, cellulose acetate and triacetate fibers.

Phthalocyanines

Phthalocyanines have a complex structure with a central metal atom. The dyes in this group are obtained by reacting dicyanobenzene in the presence of a metal halide (Cu, Ni, Co, Pt, etc.).

Nitrated and nitrosated dyes

Nitrated and nitrosated dyes form a relatively old class of dyes and very limited in number. They are currently still used, due to their very moderate price linked to the simplicity of their molecular structure characterized by the presence of a nitro group (- NO2) in the ortho position of an electron donor group (hydroxyl or amino groups. ).

You should know that the majority of organic, synthetic dyes (we should not call them pigments since they are soluble in water but dye or colorant), must be wet, with alcohol or a silicone wetting agent in order to be able to mix them intimately with water, whereas with an oleaginous or non-polar binder such as linseed oil, this is not always necessary. Another important point, these dyes require a lot of oil during grinding, much more than inorganic pigments, in general they require more than 50% of oleaginous binder to constitute a suitable oil paint, the brilliant Hansa yellow for example requires 110% oil for its grinding. However, the amalgamation in oil and the grinding of these pigments is very simple, sometimes a wetting of 10 minutes is enough to constitute a painting, but I advise you to always grind your pigments with a wheel on the marble, the amalgam is then perfect and does not risk trapping air bubbles in the paint, unlike a simple wetting of a powder with a binder in a container. I wouldn't go into the (chemical) details of all of their constituents, their names and their chemical constituents do not evoke anything very colorful or very poetic and therefore they are very difficult to understand. [50] You really have to be informed of the Color Index of each dye in order to be able to get an idea of ​​these colored substances at our disposal, they are more of the order of organic chemistry, you have to be an enlightened chemist to find your way around. This cohort of the most diverse dyes. It is enough to know some of these dyes and know that they can be used in artistic painting, keeping in mind that with oil painting it is better to use high performing inorganic pigments rather than synthetic dyes, unless used as a glaze. The problem does not arise with aqueous binders such as acrylic, the Enluminure, ink, etc. .... Besides an absolutely incomparable range of pigments, the dyes are beautiful, their luminosities are clear and they have an incredible presence, but they are invasive, especially some red and orange, compared to some iron oxides natural, therefore they must be used in small quantities at the start. I will deal here with the most common dyes in artistic painting. All data on these dyes comes from the technical data sheets of the manufacturers or suppliers of these dyes. http://bit.ly/Pigments-Industriels


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SYNTHETIC DYES HANSA YELLOW ARYLAMID

Color Index Pigment Yellow PY 3 11710 Chemical Formula: C16H12Cl2N4O4 Chemical description: Monoazo 2– [(4 - chloro-2– nitrophenyl) azo] - n - (2– chlorophenyl) -3 - oxobutyramide. Oil absorption: 32%

SYNTHETIC INDIAN YELLOW[132]

Colour Index Pigment Yellow PY 150 12764 Chemical Formula : C8H6N6O6Ni or C18H15N5O5 Chemical Description, Mono Azo Nickel Complex, Nickel Azomethine. Very good resistance to light. Moderate resistance to acids and alkalis. Good resistance to lime. Oil absorption ≈ 55% - 27 g of oil for 50 g of coloring. Compatible techniques: Oil, Acrylic, Water-based paint, Fresco.

hansa yellow arylamid Synthetic Indian Yellow PY150

Irgalith yellow

Colour Index Pigment Yellow PY 13 21100 Chemical Formula : C36H34Cl2N6O4 Chemical description : Diarylide Oil absorption: 55%. Very beautiful yellow pigment. Incompatible with oxidizing agents.

irgalith Yellow

Pyramid Yellow or Anthrapyrimidine

Colour Index Pigment Yellow PY 108 68420 Chemical Formula : C30H15N3O4 Chemical description : Anthrapyrimidine Oil absorption: 55%. Very good resistance to acids but moderate resistance to alkalis. Possible techniques: Oil, Acrylic, Tempera, Water-based painting.

Pyramid Yellow


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SYNTHETIC DYES ISOINDOLE YELLOW

Colour Index Pigment Yellow PY 109 56284 and Pigment Yellow PY 173 561600 Chemical Formula for PY 109: C23H8Cl8N4O2 Chemical description: Tetrachloro isoindolinone resistant to alkalis and acids. Oil absorption: 60 to 65%. Possible techniques: Oil, Acrylic, Tempera, Waterbased painting.

IRGAZIN® Orange DPP-RA and Orange-yellow Irgazin isoindolinone

Colour Index Pigment Orange PO 73 561170 PO 61 and PY 110 56280. Chemical description : Diketo-pyrrolo-pyrrol et tetrachloro-isoindolinone for PY110 Chemical Formula : C26H28N2O2 for PO73 Density: 1.30. Oil absorption: 40 to 60%. Very resistant to alkalis and acids. Possible techniques : Oil, Acrylic, Tempera, Water-based painting, Fresco. IRGAZIN yellow orange PY 110

Isoindole yellow

IRGAZIN® yellow greenish

Colour Index Pigment Yellow PY 129 48042 Chemical description: Copper azomethine complex. Chemical Formula: C17H13NO2 Advantageously replaces stil-de-grain. resistant to alkalis and acids. Oil absorption 60%. Possible techniques: Oil, Acrylic, Tempera, Waterbased painting, Fresco, Violin making.

IRGAZIN® yellow greenish

IRGAZIN Orange PO 73

ISOINDOLE ORANGE

Colour Index Pigment Orange PO 61 11265 Chemical Formula : C29H12Cl8N6O2 Chemical description : Tetrachloro isoindole Density : 1.79g/cm3. Refractive index : 1.7 Resistant to alkalis and acids. Oil absorption : 50 to 60%. Possible techniques: Oil, Acrylic, Tempera, Water-based painting, Fresco, Cement.

Isoindole Orange


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SYNTHETIC DYES Scarlet red or Cromophtal Scarlet RN

Colour Index Pigment Red PR 166.20730 and PR 168.59300. Chemical Formula : C40H24Cl4N6O4 Chemical description : Disazo condensation. Lightfastness = 8. Heat resistance <340 ° C. Density = 1.5. Oil absorption ~ 50%. Resistant to alkalis and acids. Compatible with : Oil, Acrylic, Tempera, Water-based paint, lime, Fresco, Cement.

Indanthren Blue

Colour Index Pigment Blue PB 60 69800 Chemical Formula : C28H14N2O4. Chemical description : Anthraquinone. resistant to alkalis and acids. Oil absorption: 37%. Possible techniques: Oil, Acrylic, Tempera, Waterbased painting, Fresco, Cement.

Indanthren Blue

Heliogen Green and bluish Phthalocyanine Scarlet Azoic Red PR166

Heliogen blue or phthalocyanine

Colour Index Pigment Blue and PB 15 : 1.74160 PB 15 : 3.74160 et PB 15 : 6.74160. Chemical Formula : C32H16CuN8. Chemical description : Copper phthalocyanine. Resistant to alkalis and acids. Oil absorption: 40 to 50%. Possible techniques : Oil, Acrylic, Tempera, Water-based painting, Fresco, Cement.

Heliogen blue

Colour Index Pigment Green PG 7 74260 Chemical Formula : C32Cl16CuN8 and C32H2CI15CuN8. Chemical description : halogenated copper phthalocyanine. Oil absorption: 40 to 50%. Incompatibility: Avoid strong oxidants such as peroxides, chlorates, perchlorates, nitrates and permanganates. Insoluble in water. Heat resistance 250 ° C. Resistant to alkalis and acids. Possible techniques: Oil, Acrylic, Tempera, Water-based painting, Fresco, Cement.

Heliogen Green


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SYNTHETIC DYES Heliogen Green and yellowish Phthalocyanine Colour Index Pigment Green PG 36 74265 Chemical Formula : C32Br6Cl10CuN8 Chemical description : Copper (1,3, 8,16, 18,24– hexabromo-2, 4,9, 10,11, 15,17, 22,23, 25 – decachloro-29 H, 31H-phthalocyaninato [2– ] – N29, N30, N31, 32). Incompatible with oxidizing and reducing agents. Insoluble in water. Oil absorption: 60 to 70%. Possible techniques: Oil, Acrylic, Tempera, Water-based painting, Fresco, Cement.

Purple Alizarin Brilliant

Colour Index Pigment Violet PV 5:1 · 58055:1 Chemical Formula : C14H7NaO7S. Chemical Constitution: quinizarin-2 sulfonic acid. Chemical description: Anthraquinone dye. Resistant to alkalis and acids. Possible techniques: Oil, Acrylic, Tempera, Lime and Fresco.

Purple Alizarin Brilliant Heliogen green

DIARYLIDE YELLOW HR

Colour Index Pigment Yellow PY 83 21108 The compound is synthesized from three components. Treatment of 2,5-dimethoxy-4-chloroaniline with diketene gives an acetoacetylated aniline. This compound is then coupled to the bisdiazonium salt obtained from 3, 3'-dichlorobenzidine. Chemical Formula C36H32Cl4N6O8. May cause severe eye irritation. It is a very luminous pigment very resistant to light and medium resistance to acids and alkalis. Oil absorption ~ 60%. Compatible with: Oil, Acrylic, Tempera, Water-based paint. pH ~ 7 - 9. Density ~ 1.5 Kg / liter

Orange and Yellowish Orange from Paliotol

Colour Index Pigment Orange PO 59 12075 and PO 67 et PY 139 56298. Chemical Formula : C16H10N4 and C16H9N5O6. Chemical description: Mono Azo Nickel. Requires a wetting agent with water. Do not treat with hydrochloric acid. Density: 1.52 Kg/l. Refractive index: 1.71 Oil absorption: 95%. Paliotol PY 139 Yellowish Orange is resistant to acids but not to alkalis, while PO 59 is resistant to both acids and alkalis. Compatible with Oil, Acrylic, Tempera, Water-based paint, Lime and Fresco.

Diarylide Yellow HR

Yellowish Orange from Paliotol


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SYNTHETIC DYES IRGAZIN® RED DPP BO

Colour Index Pigment Red PR 254 56110 Chemical Formula : C18H10C12N2O2 Chemical description : Diketo-pyrrolo-pyrol Density 1.5 Kg / l. Oil absorption ~ 72% Possible techniques: Oil, Acrylic, Tempera, Waterbased painting, Fresco, Cement.

Hostaperm® Pink E and Hostaperm® Red

These are varieties of Quinacridone transparent according to crystal form and substitution type, different orange, brown, scarlet, magenta and purple quinacridone exists. Hostaperm Pink E transparent from Color Index PR PR 122 73915 from Chemical Formula C22H16N2O2. Red is also called Monastral Red; Cinquasia Red or Monastral Red, from Color Index PV 19 73900 from Chemical Formula C20H12N2O2. The two pigments are resistant to alkalis and acids: 5 on a scale of 8. hostaperm rose: pH: 5.5 to 8. Density: 1.47 Kg / l. Stable up to 200 ° C. Oil absorption ~ 90 to 100%. Compatibility: Oil, Acrylic, Tempera, Waterbased paint, lime, fresco and cement.

Hostaperm Red PV 19 73900

IRGAZIN red

Purple Thioindigoid

CI Pigment Red PR 88 73312 4,4,7,7-tetrachlorothioindigo. It is a deep purple red.

Thioindigoid purple

Hostaperm Pink PR122 73915

HANSA BRILLIANT YELLOW

Colour Index Pigment Yellow PY 74 11741 Chemical Formula : C18H18N4O6 Constitution Chimique : Butanamide, 2– [2- (2-methoxy-4-nitrophenyl)diazenyl] – N – (2– methoxyphenyl) -3 – oxo – . Monoazo-Arylide-Arylamide yellow dye. It is a primary yellow useful in admixture with other pigments. It is a slightly transparent yellow. Oil absorption: 110%. Reserve it for the glacis. Excellent resistance to pure light. Good resistance to acids and alkalis. Possible techniques = Oil, Acrylic, Tempera, Water-based painting, Fresco. Hansa yellow PY 74 11741


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SYNTHETIC DYES "Sudan" dyes Black Soudan B

Colour Index Solvant Black 3 26150 Also called Solvent Black 3, Ceres Black BN, Black Fat HB. Chemical Formula : C29H24N6 Average mass: 456.541 Da Mono isotopic mass: 456.206238 Da Name of the chemical components constituting it : 2,2-Dimethyl-6 - [(E) - {4 - [(E) -phenyldiazenyl] -1-naphthyl} diazenyl] -2,3-dihydro-1H-perimidine. Sudan Black B is formed by the diazotized complex coupling of 4-phenylazonaphthalenamine-1 with 2,3– dihydro-2, 2-dimethyl-1 H-perimidin. [1] Therefore, the main expected product is 2,3– dihydro-6-2, 2dimethyl - [(4-phenylazo-1-naphthalenyl) -azo] -1 Hperimidin. Melting temperature between 120 and 124 °C. Density = 1.26 Kg / l It is insoluble in water. Moderate solubility in ethanol. Do not inhale dust and avoid the formation of dust clouds. In which case wear a mask. It is an azo dye, a dye that comes in the form of a fine black to very dark brown crystalline powder that colors black blue. It is a transparent dye that can be used to color a variety of materials. Sudan Black B is a lysochrome (oil and fat soluble dye) primarily used to demonstrate the presence of triglycerides in frozen sections. Sudan B black is used to improve fingerprinting. It is useful for detecting contamination of fats with oil and grease. However, the dye resulting from the above reaction product actually contains several and up to 42 dyes which can be fractionated. Sudan Black B contains two main blue components, SSB-I and SSB-II.

SSB-I is written as follows: 2,3– dihydro-2, 2-dimethyl-4 - [(4-phenylazo-1-naphthalenyl) - azo] - 1Hperimidin. For SSB-II its structure has been confirmed: -2,2– dimethyl-2,3 - dihydro 6 - [(4-phenylazo-1-naphthalenyl) - azo] - 1H-perimidin [72]. Sudan Black B is used for coloring other varieties of dyes called "Sudan". These dyes are as follows.

Oil Red O

C.I Solvant Red 27 26125, Soudan red 5B Chemical Formula : C26H24N4O Nom chimique : 1 – (2,5– dimethyl -4 – [2-5– dimethylphenyl] phenyldiazenyl) azonapthalen-2-ol Oil Red O is an advantageous replacement for Sudan III and Sudan IV, as it gives a much more intense red tint; thus the spots are much easier to discern. In pyrotechnics, Red O oil is used in certain red-tinted smoke compositions. It is also used for the formulation of dyes.

Soudan Black

cell lines stained with Oil Red O

Soudan III

Their chemical structures have been determined using two-dimensional thin-layer chromatography, column chromatography, its IR absorption, mass, H1NMR and C13-NMR spectroscopy has been proven by alternative synthesis.

C.I. Solvant Rouge 23 26100, also known as Sudan Red BK, Fat Ponceau G, Cerasine Rouge. Chemical Formula : C22H16N4O Chemical name: 1- (4- (phenyldiazenyl) phenyl) azonaphthalen-2-ol. Used to color non-polar substances such as oils, fats, waxes, various hydrocarbon products and acrylic emulsions.


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SYNTHETIC DYES Eriochrome Black T ou Diamond Black

Sudan III

Soudan IV

CI Solvant Rouge 24 26105, Crimson lipid, Oil Red, Oil Red BB, Rouge Fat B, Oil Red IV, Scarlet Red, Rouge écarlate NF, Scarlet Red Scharlach, Scarlet R. Chemical Formula: C24H20N4O Chemical name : 1- (2-methyl-4-(2-methylphenyldiazenyl) phenyl) azonapthalen-2-ol). It has the particularity of being used as a colorant in fuels, so it is called Red Tax Oil.

Sudan IV

C.I. Mordant Black 11 Sodium salt 3-Hydroxy-4 - [(E) - (1-hydroxy-2-naphthyl) diazenyl] -7-nitro-1-naphthalenesulfonate. Chemical Formula: C20H12N3NaO7S Average mass 461,380 Da It is an azo dye. Eriochrome is a registered trademark of Huntsman Petrochemical, LLC. In its protonated form, Eriochrome Black T is blue. It turns red when it forms a complex with calcium, magnesium or other metal ions. Besides its use as a dye, Eriochrome Black T is also used to detect the presence of rare earth metals. Eriochrome Black T

Tartrazine

Yellow Sudan 3G also known as fat Yellow 3g also known as Color Index Solvent Yellow 16 12700, 656870. It is an azo dye with a light yellow tint. Chemically, it is 4-phenylazo-1-phenyl3-methyl-5-pyrazolone or 2,4-dihydro-5-methyl2-phenyl-4- (phenylazo) -3H-pyrazol-3-one. It is soluble in fats and oils. Sudan 3G Yellow Dye is used as a colorant in inks, some cosmetics, printer toners and inkjet printer cartridges. In pyrotechnics, it is used in yellow smoke. This food coloring is not authorized in France. Yellow Soudan

Colour Index Acid Yellow 23 19140. Chemical Formula C16H9N4Na3O9S2 Tartrazine is a synthetic orange-yellow azo dye primarily used as a food coloring. It is also known as E102, and trisodium 1- (4-sulfonatophenyl) -4- (4-sulfonatophenylazo) -5-pyrazolone3-carboxylate). Mol weight 534.356 g / mol. It can be used to tint all kinds of oils, plasters or paints.

Tartrazine


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ORASOL© DYES BY BASF®

BASF® ORASOL © dyes

There is a whole range of synthetic dyes such as Nigrosine, a wood stain. Preparation of azine dye and azo dye. ORASOL® dyes are a family of wood dyes or for tinting oils in yellow, blue, red, brown, pink and orange. They are soluble in most solvents, they are very shiny and they have good stability. All these dyes are easily soluble in a mixture of 80% ethyl alcohol, 5% water and 15% methoxypropanol PM, propylene glycol ethers are good dispersants and excellent solvents for paints, resins and dyes. For most applications, 1 to 5 g of colorant is sufficient to tint 1 liter of binder. These are dyes for specific use, such as tinting wood, for tinting oils, etc. ... They are transparent and therefore can be used in painting in glazes. C.I of a few of these dyes out of a total of 26 in the full range: 1. C.I. Solvent Yellow 146 for 4GN Yellow 2. C.I. Solvent Blue 70 for Blue 855 3. C.I. Solvent Blue 67 for Blue 825 4. C.I. Solvent Yellow 88 for yellow 152 5. C.I. Solvent Orange 11 for orange 247 6. C.I. Solvent Red 122 for Red 395 7. C.I. Solvent Red 127 for Pink 478 You will find a few of these dyes. Here is the address if you are interested in this class of dyes: http://bit. ly/Colorants-Orasol. [130]

3.ORASOL® Blue 825

2.ORASOL® Blue 855

5.ORASOL® Orange 247

6.ORASOL® Red 395

7.ORASOL® Pink 478

4.ORASOL® yellow 152

1.ORASOL® yellow 4GN


PROTEAN PIGMENTS The Bitumen

Judean Bitumen, Asphalt (one component), Gilsonite Color Index Natural Black NBk 6 Natural asphalts or bitumens are hydrocarbons composed exclusively of carbon (C) and hydrogen (H) atoms, which are found in the natural state in the form of black and compact sediments, solid, striped by a point metal, but not by the fingernail. Bitumen melts easily in oils and certain solvents, it constitutes the residual state of a natural distillation or evaporation of old slicks of asphaltic petroleum, which are similar in their composition to the asphalt which coats the roadways. In 2021, bitumen is obtained by artificial distillation of oils of the same types. Certain pigments in the broad sense such as bitumen, carbon black and Van Dyck brown are considered to be oxidation inhibitors, so they are therefore antidrying. Asphalts are rarely found free in sediments, but most often impregnated in sandstones or marls = oil shales, asphalt sands and limestones.

Bitumen is very harmful in painting if it is not properly insulated and if the deep and adjacent layers are not protected by an insulating shellac or oleoresinous varnish (Rubens medium). We cannot consider bitumen as a pigment, but more as an oil-soluble dye, possessing thermoplastic properties : it's a substance that softens under the effect of heat without modifying its properties, properties, that in this case for bitumen, we speak of redissolution. It is used in oleoresinous mixtures of Rubens medium type or liquid varnish, taking care to protect the undercoats and the parts in contact with it with an insulating shellac varnish N°36 or N° 36 -1, depending on the nature of your painting. Shellac is the only resin capable of preventing the phenomenon of migration of such soluble substances present in certain pigments such as umber and certain dyes such as bitumen. These soluble agents inexorably end up invading the entire painting, through the action of softening and redissolution of the organic substances that constitute them, they thus end up migrating into the deep layers of the works on which they are applied. Very good article on bitumen [22].

Natural bitumen By Daniel Tzvi via Wikimedia Commons

Bitumen

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PROTEAN PIGMENTS The Van Dyck brown

Color Index Natural Brown NBr 8 77727 Also called earth of Cassel or earth of Cologne. Genuine Organic Van Dyck Brown is a kind of lignite, consisting of earth, peat, iron, alumina and silica. Under the name Brun Van Dijck, there is a very beautiful brown from the Czech Republic made up of bitumen, lignite and iron. Lignite from the Latin lignum = wood, is a sedimentary rock composed of the fossil remains of plants, considered as an intermediate rock between peat and coal that can contain up to 75% carbon. PBr9 Brown 77430 the synthetic reddish inorganic variety comes from strong calcination, to sintering, ocher, followed by grinding, a copper ferrocyanide of Chemical Formula CuSO4 + Fe2 (CN) 6.

Inorganic Van Dyck Brown

Van Dyck Brown of the Czech Republic in natural light

The synthetic variety comes from colcotars, calcined or natural vitriol, chalcitis which is a ferrous oxide (containing copper, which is calcined) or sulfuric acid residue. With a very deep reddish brown shade, Van Dyck Brown is a pigment, straightforward and pleasant to use, but very difficult to find pure. Oil absorption: 30 to 40%. It is incompatible with oil. The organic variety should only be used with aqueous techniques. With a binder with saponified shellac, it will be made more stable and above all much less fleeting. See ink recipe N ° 36 bis. It is a very beautiful blackish brown supported halfway between dye and pigment used as wash and ink. See at Browns.

organic Czech Van Dyck Brown in bright light

Genuine Van Dyck Brown NBr 8


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PROTEAN PIGMENTS The Shungite Black

Colour Index pigment Black PBk 6 77266 Chemical Formula : ShC Natural amorphous variety of graphite, which gives an intense black after grinding. It is a mixture of crystalline silicate particles in a carbon matrix. Shungite Black contains C-60 Fullerenes. The latter were discovered in 1985 by Harold Kroto, Robert Curl and Richard Smalley, which earned them the Nobel Prize in chemistry in 1996. Fullerenes C-60 are a crystalline variety of carbon, the molecule of which has a large number of atoms. Shungite is the only mineral to have these C-60 fullerenes. Shungite is found exclusively in the Karelia region in Zazhoginskoye in northwestern Russia near Lake Onega. It is exploited in this unique deposit in the world. It is a semi-opaque pigment, less transparent and more neutral than vine black. Compatible techniques: aqueous paints, Acrylic, Tempera, Watercolor and Gouache.

The Rhodocrosite

It is a mineral composed of manganese carbonate, Chemical Formula Mn2 + CO3 Its maximum manganese Mn content is around 47.8%, as some of the Mn is substituted by traces of iron Fe, calcium Ca, magnesium Mg, zinc Zn, cobalt Co and cadmium Cd. It usually occurs as granular or small crystals that are pinkish-red, brown, or gray in color, but it is rather pink when pure. Manganese ores are important in the Harz, the Carpathians, southern Spain, western North America, etc.. It is unstable when exposed to air, eventually turning brown and turning into a black oxide heated to around 650 ° C. It is incompatible with acids, with which it produces carbon dioxide. It is slightly soluble in dilute aqueous acids. Hardness on the Mohs scale ~ 3.5 - 4.5. Density ~ 3.12 g / ml at 25 ° C. It is the national stone of Argentina. As a pigment, rhodochrosite is used in the composition of ceramics, paints, colored glasses, in the bleaching of tallow and in textile printing. It can be used in aqueous techniques where its pink shade can be useful for skin tones. As a clear manganese oxide, I am thinking of using it as an oil drier, however the oil will need to be heated up a bit more without going over 260°C. Manganese is harmful, so beware of toxic fumes when cooking oils if you burn them.

Shungite By Amrith via Wikimedia

Fine Rhodocrosite 120 µm Shungite


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Chalk * White Barite

Kaolin Specific charges of inks Assists in the dispersion of titanium TiO2 Reduce the viscosity of paints Mica*

X

Bentonite

Anti- flow

Aluminum powder

X

X X

X

Tixogel**

X

X

X X

X

X

X

X

X

X

X

X

X

X X

Magnesia Refractory & anticorrosion plasters Thickening agents of aqueous and synthetic paints Filler of lean plasters

Aluminium Stearate**

Antisettling

* Best suited for aqueous polar phase paints ** more suitable for non-polar paints like oil

X

X

X X X X

X

X X

X X X

X

X

X

X

X X

X X

X X

X X X

X X

SUN RESISTANT

EXTENDER FOR PLASTERS AND PRIMERS

WATER RESISTANCE

ELECTRICAL RESISTANCE

X

Anti-corrosion paints

Antisettling

X X X

X

X

FIRE RESISTANCE

X

X*

Attapulgite Purification of oils Stabilizes wax emulsions. Matting agent Graphite Antistatic & anticorrosion paint

Quartz powder

X

Making pearly paints

Glass beads Matting agent and decorative coating. Friction aid in the making of varnishes to make the resins dissolve more easily Pyrogenic Silica Aid in the grinding of paints Matity Agent. Gels with oil Talc Specific charges of gouaches Assists the dispersion of titanium TiO2 Improves sanding Laponite Gelling agent for aqueous emulsions

Sepiolite*

DECORATIVE EFFECT

Making pastel supports Matting agent by dry friction Fillers of aqueous plasters Avoid using it with oil paints Filler Oil Paints

WEAR RESISTANCE

Pumice

CONDUCTIVITY

MOST NOTABLE FEATURES

MATTING AGENT

MATERIALS FILLERS

THIXOTROPIC

EXTENDER FOR PIGMENTS

CHARACTERISTICS OF FILLERS AND ADJUVANTS

X

X

X X X


THE FILLERS Fillers are materials that are added to paints, varnishes or binders, in order to change their rheological characteristics [55], to give them dullness, more body, to increase the volume of colored matter, as a blowing agent, as a filling agent, for the manufacture of dry pastels, printing inks, etc. ... These fillers improve pigment suspension, viscosity, thixotropy control and are excellent anti-drip agents for emulsion paints. One of the secondary functions of fillers is to increase the volume of paints by incorporating low-cost materials such as kaolin or powdered cork. They can also be used to improve the properties of films such as their impact and abrasion resistance as well as their water permeabilities. In addition to reducing cost, these admixtures also provide resistance to liquid paint sag, so the edges of painted objects are well covered. When the paint is dry, they reduce water and oxygen permeability and structurally molecularly provide film reinforcement. Bentonites, talc and mica are widely used as lengtheners, as "extenders". The supply of very fine mica is limited to about 10% of the total weight, as are talc and kaolin. But especially the mica, which reduces the permeability through the film of the plate-like particles which blocks the permeability, forcing water and oxygen to seek a longer path through the binder around the particle. Use barite and silicates as filler for oil and varnishes, as they are more stable than pure carbonates. There are about fifty fillers, mostly collected from natural extracts, the others are synthesized.

Chalks

Also known as Blanc de Meudon, Blanc de Bougival, Blanc d'Espagne, Blanc de Méru, Blanc de Champagne, Blanc de Bologna, Blanc de Marly, etc. .... Color Index Pigment White PW 18 77713 for natural chalk CaCO3 and PW 18 77720 for the synthetic variety CCaO3 named precipitated chalk which is much whiter, because it does not contain impurities, it can be produced by the passage of carbon dioxide through purified slaked lime. Natural chalk is made from pure calcium carbonate. Chalk has been known since the dawn of time, Pliny calls it "creta". The chalk is of fossil, plant or animal origin. It is a sediment resulting from deposits of various microfossils, including coccolites dating from the geological period of the Cretaceous, from which it borrowed the name. The finer grades of precipitated calcium carbonate are used to control sagging and flocculation of colored pigments in many aqueous paints. Chalk is whiter and pure, it can contain up to 99% calcium carbonate, the rest being clay. Chalk reacts with acids releasing carbon dioxide. It is poorly soluble in water, and perfect for making thin coatings with skin glue or synthetic binders, on substrates such as wood, heavy canvas, cardboard, etc..

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In some applications, the reactivity of calcium carbonate CaCO3 with acids makes carbonate-containing fillers undesirable, in particular paints subjected to humidity, the degradation of the properties of the paint film can be accelerated by rain. and the acidic atmosphere. Calcium carbonate paints should not be used in exterior latex Pure Chalk's from the career du Revoi 55190 Pagny-sur-Meuse - France paints. Water and carbon dioxide seep through the film of latex paints, calcium carbonate reacts to form calcium bicarbonate, which is soluble in water and re-penetrates out of the film. On the surface of the film, the water evaporates and the reaction reverses, leaving an insoluble calcium carbonate glaze that settles Bologna chalk on the paint film. This glaze is particularly visible on dark colored paints. This is why chalk should be avoided in oil paints, reserve it exclusively for grounds and water-based paints. Density ~ 2.4 to 2.7 Refractive index ~ 1.48 to 1.60. Precipitated chalk PW 18 77720

Gypsum Calcium sulfate Annaline

Colour Index Pigment White PW 25 77231 Gypsum is a naturally occurring mineral composed of hydrated calcium sulfate of Chemical Formula CaSO4, 2 (H2O) or CaO4S. It is one of the most common sulphate minerals. It is generally formed by the crystallization of salts contained in water, sedimentation during the evaporation of saltwater lagoons cut off from the sea. The Egyptians were certainly the first to use plaster, they obtained it by firing the gypsum between 120 and 150 ° C, it thus loses its water and turns into plaster, then turns back into gypsum in the presence of water. To use it in artistic painting, it must be killed, by purging it in a tub of water, we stir the mixture every day, for 1 month, then we throw the water, we bake breads with this plaster, we let dry and store away from moisture. It becomes soft like silk.


286

THE FILLERS There is also a filler called Annaline which is extinguished and burnt gypsum, thus making it more stable. Personally, I don't use plaster, I don't trust it. It is unsuitable in plaster if it is not killed, because it is not very stable, it cannot be used in fresco. It can be used, for the production of paper underlays, in the aqueous phase from the annaline killed plaster. As a coating, for rigid surfaces, in a synthetic binder such as Plexisol P550 in solvent phase, this coating appears to be more stable than in the polar phase. I recommend that you experiment, then let it harden for 35 days and do a surfacing and bonding test. Oil absorption between 15 and 25%.

It is used for the filtration of raw oils, in order to purify them or to make absorbent papers, to extract the oleaginous binders from too greasy paints, but also for viscosity control for glues, thickening of latex paints and gelling agent, wax-based emulsion stabilizer, as a binding agent for the granulation of powders and as a mattifying agent in paints. Particle sizes: approximately 60 µm. Density: 2.4 Kg / l. pH 8.5. Attapulgite in natural light

Attapulgite or Fuller's Earth

It is magnesium aluminum silicate that is mined near Attapulgus, Georgia (USA.). It is also called palygorskite. Some small deposits of this mineral can also be found in Mexico, where it was used in the making of Mayan blue, a variant of indigo blue. See mayan blue. Some indigos are from South America. The Mayans prepared indigo by precipitating white attapulgite, making it a brighter, more light-resistant blue than the pure plant extract. It was used in murals and in ceramic painting before the conquest of Mexico. "Fuller earth" is a catch-all term for clays or other fine-grained earthy materials, this term has no mineralogical composition or connotation. Chemical Formula (Mg, Al) 2Si4O10 (OH) • 4 (H2O). Attapulgite was used for over 40 years by industry before being recognized as a full-fledged mineral clay. The confusion arose from the fact that it was considered to be montmorillonite, as some of its properties are quite similar. It was around 1940 that it began to be studied in detail Attapulgite is a clay with a fibrous structure unlike the lamellar structure of most clays. It is used as a spray in a wide range of absorbent and filtration materials. It's a bit of clay to do everything It has a high degree of absorption. A 3% dispersion of attapulgite in water is very thixotropic, acquiring a high apparent viscosity at low shear, but becoming almost as fluid as water with intense agitation.

Attapulgite Fuller's earth in ambient light

The Pumice

Pumice stone is a colored volcanic stone, of a grayish shade, it is very light weight. It is formed by lava filled with gas. It’s so light weight that she really floats on water. It is formed from fragments of rhyolite, dacite or andesite. It is considered volcanic glass because it does not have a crystalline structure. Pumice stone is ground and used in soaps, abrasive detergents, pencil erasers and especially with waxes. The delicately ground pumice stone is added to some toothpastes and hand cleansers. I use it as an addition in coatings for rigid substrates to make rough surfaces (by sprinkling on the plaster) for dry pastels on wood and thick cardboard. It is an excellent mattifying agent for all kinds of paints by rubbing, polishing or dry sanding. Density: 910 g / liter


287

THE FILLERS

Sepiolite Pumice in powder

The Sepiolite also called Meerschaum

Sepiolite is a hydrated magnesium silicate of Chemical Formula : Mg4Si6O15 (OH)2 · 6(H2O) and also H4Mg2Si3O10. Sepiolite is a mineral of the group of clays with a fibrous structure derived from an ancient Greek term, Frenchized in "sepion" and which designates "cuttlefish bone". Sepiolite is a natural product (without asbestos), consisting of 85% sepiolite and 15% other types of clays. Sepiolite is a colloidal and thixotropic material. It has a pinkish hue, it is very light and very airy in powder form. Chemical analysis SiO2 60.5 % MgO 23.8 % Al2O3 2.4 % Fe2O3 0.9 % CaO 0.5 % K2O 0.5 % Na2O 0.1 % Loss on ignition at 1000°C = 11.3 % It is a thickening agent for aqueous suspension, polar solvents and synthetic polar phase emulsions. Add between 3 to 10%, in water-crushed paints. pH ~ 8.5 - 8.8 +/- 0.5 (10% in aqueous suspension) Apparent density ~ 60 g / l ± 30 Viscosity (6%, Brookfield) 39,000 mPas Water content ~ <10% Specific surface, BET 320 m2 / g Insoluble in water and in fats. Average fiber length ~ 2 μm Average particle size ~ 149 μm (100 mesh)

Rock crystal or Mountain Quartz

Crystalline quartz PW 27 77811 can be reduced to a pure white powder, from 0 to 150 µm. Chemical formula SiO2. Quartz and therefore silica is present as impurities in many minerals and soils. Rock crystal was very rarely used as a filler, given that it is rare, difficult to spray given its hardness of 7 Mohs and its prohibitive price !. Rock crystal is also a waste when polishing rough stones in jewelry, so small quantities are available for painting. Quartz is found in the Alps in very small quantities, in Brazil, Arkansas, Madagascar and also on the highlands of the Himalayas between 3000 and 4000 m altitude, it comes from northern India in the state of Himachal Pradesh, near the Kashmir border. Beautiful crystals are also found in the Alps. Its transparency and shine decrease if it is ground too fine. Powdered rock crystal is very useful for precious and decorative plasters as well as in miniature painting and modern the Enluminure.

Rock crystal powder ~ 10 µm.

Block rock crystal


288

THE FILLERS

Albula chalk in Switzerland

Quartz Powder

It has the Color Index of Silica Pigment White PW 27 77811 which is a chemical compound of silicon dioxide with the formula = SiO2, an essential component of igneous and metamorphic rocks. Quartz powder can contain between 99% and 99.99% silica depending on its origin. It also contains other elements such as Components

%

Al2O

4.07

Fe2O3

0.17

TiO2 CaO + MgO Na2O K2O

0.37 0,45 0.83 0.74

We prepare with quartz powder sublime coatings with skin glue on wood, of an immaculate whiteness, which we can then glaze with the flat of a stainless steel knife to give them a magnificent marmoreal polish.

Marble powder

Color Index Pigment White PW 18: 1. 77220: 1 and 77713: 1. Also called dolomite, from Chemical Formula CaMg (CO3) 2. Formed by substitution of calcium by magnesium in ordinary limestone, less sensitive to acids than chalk.Very fine powder, from 10 to 300 µm depending on the variety. I use it, mixed with quartz powder, for making superb plasters on wood and for preparing plasters for setting gold. pH ~ 10. Density ~ 2.83 Kg / l. Oil absorption ~ 15% COMPOSITION OF THE MARBLE POWDER Component Quantities CaCO3 95,5 à 99,2 % MgCO3 0,4 à 3,0% FeO3 0.035 à 0.08 % Al2O3 - 0.1 % SiO2 (silicates) 0.25 %

7.5 micron quartz powder

Alba Albula or Alba of the Pass d'Alvra

Colour Index Pigment White PW 18 77713 Variety of chalk in buff white color, from Albula in the canton of Graubünden in Switzerland. The Albula chain is a massif in the central Eastern Alps. It is a natural calcium carbonate CaCO3 with traces of magnesium carbonate as impurities. Care should be taken to remove the soluble salts by levigation. Block of Alba Albula

marble powder from Italy

Talc or chalk from Briançon

Colour Index Pigment White PW 26 77018 Formed into layered silicon SiO4 tetrahedra, two-dimensional macro-ion (Si2O5) 2 of Chemical Formula Mg3 (Si2O5) 2 (OH) 2 or Mg3Si4O10 (OH) 2. It is a natural, double hydroxylated magnesium sili-


289

THE FILLERS cate which may contain traces of nickel, iron, aluminum, calcium, sodium and other magnesium silicates such as asbestos. The proportion of magnesium defines its purity. Talc results from the weathering of magnesium silicates, in layers and fillings of crystalline schist cracks and in limestone or dolomitic rocks as well as with pyroxenes, amphiboles, olivine and other similar minerals. The talc, which is oily and soft, is very pleasant to the touch. Its lamellar structure is put to good use in paints that are viscous, matt and flexible, such as gouache, in which it is added as a filler, but also if we want to increase the resistance to light from the final paint film. I use it as a filler for gouache and opaque paints and for some plasters that I want very matt and very flexible. Talc is called chalk from Briançon (it comes from Piedmont in Italy) or soapstone. Luzenac in France is the largest talc career in the world, but it is also found in Austria (Bavaria, Carinthia and Tyrol), Italy, Hungary, and Corsica. Mohs hardness of 1 Density between 2.7 and 2.8. Refractive index ~ 1.57 to 1.60. Oil absorption from 25 to 45% ~ depending on the sample. Soapstone is a massive variety of talc, which has been heated. If the soapstone contains chlorite, it is then called "soapstone", metamorphic, magmatic and meta-magmatic rocks very poor in silica. Massive talc aggregates are nicknamed "bacon stone" because of their white color and compactness.

ture of porcelain. Kaolin of formula Al2Si2O5 (OH) 4 is composed of hydrated aluminum silicate, of the phyllosilicate family, a soft rock with a lamellar structure, which explains its propensity to viscosity and thixotropy, qualities used in water-based paints such as bucket watercolors, confectionery pastels and colored pencils, all bucket paints, high quality plasters and white lacquers. Kaolin is chemically very resistant, even with strong acids. TYPICAL COMPOSITION OF A KAOLIN Components Quantities SiO2 46 à 49% Al2O3

35%

MgO K2O Na2O CaO

0.2% 1% 0.07% 0.02%

kaolin Bacon stone, a block of natural talc © 2016 David Damour

Kaolin

Color Index Pigment White PW 19 77004/77005 It is a naturally occurring hydrated aluminum silicate, kaolinite. Chemical Formula of purified kaolin Al4 (Si4O10 [OH] 8). Its origin comes from feldspars and silico aluminate clays very widespread in nature. It is a mineral, originally used in China, but found all over the world. Breton and Limousin deposits are exploited in France. We can distinguish the lean kaolins, containing a little silica and which are used to make lacquer pigments, and the fatty kaolins, indicated as fillers for paints, they are also used for the manufac-

Kaolin decreases crack formation and increases the stability of coatings. In paints and lacquers, kaolin not only acts as an inert filler, it also produces quality films. Kaolin prevents the sedimentation of pigments in liquids, given its thixotropic and mechanical qualities; it has increased reflection properties, a significant covering power with improvement in the hardness of the primed surfaces. It is also used in ceramics and for coating papers. Oil absorption ~ 46%. Density ~ 2.6 Kg / l. Water absorption ~ 8%. Refractive index ~ 1.55


290

THE FILLERS

Barite White also known as Barium White Color Index Pigment White PW 22 77120 for the natural and PW 21 77120 for the artificial variety. Chemical Formula BaSO4 with diamond structure. It is a barium sulphate obtained naturally from barite or fixed white, more brilliant, which is obtained artificially by precipitation processes. It has low covering and hiding power, and a medium to hard structure. It is one of the most stable pigments, which is why it is used to lengthen pigments and paints in order to increase their density and due to its low oil absorption it does not affect the consistency of paints. It is also used to lengthen too dense titanium white and for making white oil prints on canvas and coatings with skin glue on wood. It mixes very well with all binders. Density ~ 4.5 g / cm3. Oil absorption ~ 15%. Refractive index ~ 1.637 to 1.648.

Magnesia is a very white material

Ashes of bones

Barite Sulphate

It is tricalcium phosphate with the chemical composition : Ca3 (PO4) 2 Ashes of bones are made by calcining animal bones. It often contains additional traces of calcium, carbonate and other minor constituents. The powdered ashes of bones are a slightly sandy grayish white. They are used for their abrasive properties, on paper and parchment. They were widely used in the Middle Ages before the invention of sandpaper, in the preparation of papers for the silver tip technique. Ashes of bones gives the paper mordant. It is also used as an adjuvant in lime paints.

Magnesia

It is carbonized magnesium oxide also called magnesia, which has the Chemical Formula MgO and MgCO3 for magnesium carbonate. Magnesia is extracted from certain calcite minerals such as magnesite, either from magnesium chloride which is extracted from seawater or from underground brines. It is calcined between 700 and 1000 ° C, then used as a filler for paper and certain synthetic paints. It has very good heat resistance. It is used in the plasters that we want refractory; for paper sizing, the coatings are thus made more resistant to corrosion. It is also used in the formulation of printing inks. It is also a food additive E504 and E504i, an acidic pH regulator and E530 an anti-caking agent which limits the agglutination of particles in a powdered product in order to ensure its fluidity. Density ~ 2.16 Kg / l at 20 ° C. pH ~ 10 to 11 at 20 ° C, 50 g / l. Ashes of bones


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COAGULATORS Coagulators are materials, most generally inert, used to give body to paints, lacquers and varnishes, they can also serve as an agent for purifying oils, as a cleaner and in order to extend the properties of paints, improve pigment suspension, viscosity, thixotropy control and they are excellent anti-drip agents for emulsion paints.

Organic clays

Sodium montmorillonites with high exchange capacity and hectorite are specially treated to form organic clays. In this process, the exchangeable ions are replaced by organic compounds such as alkyl amines. These organo-argillaceous montmorillonites are used as thickeners in paints, to gel organic liquids and recently created nanocomponents. Nanomontmorillonites are treated with organic molecules which interact with polymers to make very resistant products. The mechanisms of interaction and the way in which the organic reagents are arranged on the mineral substrate have been described in the literature. Naturally hydrophilic montmorillonites can be modified to become organophilic or hydrophilic. For use with aqueous binders, hydration and pH correction require careful research into the formulation, which takes a lot of research and time to craft good recipes.

Tixogel® VZ

Structuring recipe for oil painting

Add 0.5% (of total paint weight) of Tixogel® to 1% ethyl alcohol. Ground with pigments, it is one of the best structuring agents with aluminum stearate, for oil paints and oleoresin binders. More specifically, Tixogel® VZ is a thixotropic and anti-settling agent in application areas such as medium to high polarity systems, mixed with aliphatic and aromatic hydrocarbons, basic printing inks, synthetic lubricants. in combination with wetting agents, all painter's oils, alkyds, polyurethane binders, etc. .... Specific weight 1.7 Kg / l Apparent density of 250 to 400 g / l Primary particle size: 1 to 5 µm Maximum water content 3% Stability between 200 and 250°C

Suitable solvents

Alcohols and ketones (> 4 carbon atoms), ethylene glycols, ethylene glycol ether, propylene carbonate mixed with aromatic hydrocarbons, aliphatic hydrocarbons, phthalic acid esters, vegetable oils, epoxy resins, polyethers and polyurethanes. Tixogel VZ gives good results if the biological systems mentioned above are mixed with methanol, ethanol, propanol, butanol, methyl ethyl ketone, methyl isobutyl ketone, acetone and acetate ethyl. The amount of polar solvents should not exceed 20% of the total system.

It is actually smectite, a group of clay minerals consisting mainly of montmorillonite as well as hectorite. [108]. Tyxogel® VZ is composed of 97% organic clay (organoclays) and 3% silica and quartz. Tixogel is a white to yellowish powder which becomes lighter with age, it is transparent in the binders. Approximately 0.5 to 1% of Tixogel®, based on the total amount of oil paint, provides optimum consistency. Tixogel makes oil paints ductile and creamy like butter. It prevents the flow of paints, it reduces the formation of runs and increases the roundness under the brush. The Tyxogel® VZ data sheet from "Rockwood specialties inc / southern clay products" provides extensive information on the product [107].

Tixogel recipe as a thickener

As a thickener for oil paints: 5 g of Tixogel® are mixed with 30 g of turpentine, let solidify and then mixed with 5 g of ethyl alcohol.

Tixogel VZ


292

COAGULATORS Tips for practical use

For optimal gelation, Tixogel VZ should be dispersed in solvents using high shear forces. A stirrer (mixer) operating at 1000 rpm minimum will usually suffice. First, prepare an 8-10% mixture in any solvent. After dispersion in this solvent (approx. 5 to 10 min at 1800 rpm), the polar activators are added for optimal gelation, for example: Methanol / H2O 95/5 - 30% dry Tixogel ratio Ethanol / H2O 96/4 - 35% dry Tixogel ratio Acetone 60% relative to Tixogel VZ dry Gels can be prepared as follows 1. load the solvent into a mixer 2. Slowly add Tixogel VZ (10% by weight of the total pre-gel) in a blender. 3. Mix on high speed for 5 minutes. 4. Add the polar activator. 5. Mix on high speed for 5 minutes. Wetting agents should be added only after Tixogel VZ has been activated. Less than 4.5 kg for 380 liters of paint will control the sagging and / or suspension of pigments, i.e. 11.84 g per liter. With the exception of paints rich in zinc and anti-fouling coatings, in this case much higher amounts of Tixogel® VZ must be incorporated. Depending on the desired consistency, 2-8% Tixogel VZ is used in paint systems. These preparations are then ground by hand using a wheel or using a stirrer such as a blender. If Tixogel VZ is to be incorporated directly into a paint, the product must first be wetted or activated with a sufficient amount of a polar solvent, then homogenized. The moistened Tixogel VZ is then agitated in the biological system by means of a stirrer, it is then ground with the paint and the binder. A surfactant such as lecithin i.e. phosphatidylcholines, a lipid formed from a choline, a phosphate, a glycerol and two fatty acids, can aid the action of Tixogel ® VZ. Care must be taken, however, to ensure that the surfactant used is compatible with the paint system and does not cause incompatibility. Tixogel® VZ is resistant to dilute acids and alkalis.

Chemical Formula (Na, Ca) 0.3 (Al, Mg) 2Si4O10 (OH) 2 • nH2O. Its name of bentonite was given to it by an American geologist. It is a geological stratum, "Fort Benton" in the mountains of Montana, USA. The best bentonites are those which carry sodium as an exchangeable cation and are therefore very colBentonite loidal and completely dispersible. Bentonite swells when wet, it can absorb 5 to 6 times its dry mass in water. Bentonite is a useful absorbent in aqueous solutions as well as in oils.

Applications :

Used to bleach minerals, animal pigments, vegetable oils, fats and waxes. It increases the resistance of emulsions, for making cleaning soaps, in restoring works of art (soaps that contain bentonite are particularly effective in cleaning oily dirt). Used in the purification of raw oils (bentonite absorbs tarry impurities). Also used as a thickener for water and oil colors. ~ 1.5% is used to thicken oil colors.

Polyamides

Polyamide thickeners are available in combinations of different carboxyls and amines. Some of these adjuvants are considered to be polymers. The thickening effect is partly explained by chelation. Their thickening effect in paints is partly achieved by micelle formation resulting from their hydrophilic and hydrophobic ends. Polyamides swell in some organic solvents, their molecular volume increases, so the viscosity also increases. Polyamide agents are available commercially, but not at retail at this time. They are generally recommended at a use level of 2% or less to provide thixotropy in solvent based paints and high solids paints.

Conservation

Tixogel® VZ can be stored for more than two years in a dry place at temperatures between 0 ° C and 30 ° C, protected from light. I personally stored Tixogel VZ in a full, capped bottle, for over 10 years on an experimental basis and the product had not lost its properties with a paint ground with siccativated clear oil .

Bentonite

It is a generally impure aluminum phyllosilicate which consists of montmorillonite, a mineral composed of hydrated aluminum and magnesium silicate and secondary minerals such as Quartz ~ 5 - 9%, Mica ~ 1 to 6% and feldspar ~ 1 - 4%.

Be careful, they can affect the adhesion of the intermediate coats in some paints, because they reduce the surface tension, use them instead with alla prima paints on rough surfaces or sand between each coats. Certain polyaminoamide-based products are mainly used in binders, in particular thixotropic alkyd resins.


293

COAGULATORS BK®-883

Rheological additive for solvent-based systems. It is an organic clay, a tetra-alkyl-ammonium bentonite, for low to medium polarity solvent-based systems. 1. Produces reproducible thixotropic consistency over a wide temperature range. 2. Allows the suspension of particles, which prevents sedimentation of pigments and fillers. 3. Produces a strong film, enhancing action in organically bound systems. The dosage of the polar activator, which can be 95 ° ethanol, 95 ° methanol, acetone or propylene carbonate, is 40% to 60% by weight of BK®-883. Density 1.7 Kg/l

its high thermal conductivity, as an opacifying agent in the manufacture of papers and in the control of the viscosity of inks. It is a very good anti-sedimentation agent for oils placed in tubes.

Aluminum Hydroxide

Les Stéarates d’Aluminium

BK-883

Aluminum Hydroxide

Color Index Pigment White PW 24 77002 It is Chemical Formula Al [OH] 3 Aluminum Hydroxide which contains 42.0% Al2O3 alumina. It is the most stable form of aluminum, which occurs as a white crystalline powder. Oil absorption ~ 70% COMPONENTS Al [OH] 3 Fe2O3 SiO2 Na2O

% de 99.8 à 99.6 de 0.01 à 0.01 de 0.005 à 0.008 de 0.1 7 à 0.32

Refractive index 1.568 to 1.587. Loss on drying 18.0% maximum pH (10% in suspension) 5 to 6 Density ~ 2.42 to 2.45. Molecular weight = 78 g / mol. It is used as a filler for rubber, plastics, fibers and papers in order to obtain increased heat resistance (it is a flame retardant), as an electrical insulator, for

Tri Aluminum Stearate, Crude Molecular Formula: C54H105AlO6, consisting of aluminum soaps of C16C18 fatty acids. Metal stearates are compounds of long chain fatty acids with metals of various valences. The most notable metal stearates are the metal stearates of aluminum, calcium, magnesium and zinc. The most interesting are produced from fatty acids derived from natural sources, with a predominance of sources which mainly contain stearic acid and palmitic acid. Due to the OH group present in the fatty acid molecule 12 - hydroxystearates are generally more soluble in polar solvents and their melting point is higher than the metal salts of predominant stearic and palmitic acid mixtures. Aluminum greases are very hydrophobic and are characterized by excellent transparency and good adhesion to metal surfaces. Due to their excellent water resistance, aluminum stearates are insoluble in water, weak alcohols, esters and ketones. They dissolve into a gel when heated in benzene, aromatics, halogenated hydrocarbons as well as natural and mineral oils such as linseed and walnut oils. Aluminum stearates are produced only by precipitation. There are three possible combinations of aluminum with fatty acids. The ratio of aluminum to fatty acid does not necessarily correspond to stoichiometric values. cf. glossary. Any ratio is possible between the extremes of 1: 1 and 1: 3, therefore, there are many varieties of aluminum stearates, usually named mono, di - or tri aluminum stearate, whose properties differ from those of one from the others with regard to physical properties such as melting point, free fatty acids and in particular gelation properties. Oils with low viscosity are much better thickened by aluminum tri- and di-stearate, while highly viscous oils form a stiffer gel when combined with aluminum di or monostearate.


294

COAGULATORS

Aluminum stearate therefore does a good job of transforming an oily paint into a gel. A small amount of aluminum stearate gives oil paint a smooth consistency. The advantage of using it is that you can pre-prepare an oil concentrate with aluminum stearate and add it to the paint when desired. It prevents the separation of pigment and oil in the tube. It significantly thickens the varnishes. Aluminum stearate powder is also considered a good lubricant, it is an off-white powder with a very light waxy appearance that mixes with the oil to maintain its transparency. Wear a mask. [55] THE COMPONENTS OF TRI ALUMINUM STEARATE

Ashes Free fatty acids Melting interval Humidity Density Purity

Magnesium and Lithium silicate, it is also a thixotropic agent identical to Laponite RD

9-11% 4-9% Between 150 et 160°C < 1, 5% 380 g / l ± 20% ~ 97%

Aluminum Stearate

LAPONITE RD, XLG, D, XL21 for Gels

they may neutralize the effects. Laponite RD should always be pre-dispersed and fully hydrated in water. It is possible to use Laponite as a secondary film-forming binder, by selecting a suitable primary binder and wetting agent, thus producing clear paints, very flexible and resistant to humidity. When mixed with skin glue or casein, it gives very plastic films. See in Tempera. It is a high performance film-forming agent.

10 g of Laponite + 100 ml of water = gel made with a mixer. For heavy impasto, add 10% plasticizer such as silicone antifoam.

Laponite® is a synthetic material, a silicate of Magnesium, Lithium and Sodium which is presented in layers. It is insoluble in water, but swells when hydrated and thus gives clear and colorless colloidal dispersions, which make it possible to make thixotropic gels obtained from 2% in concentration even with tap water. These applications to give a wide range of water-based products and formulations include industrial paints and detergents, gouaches, watercolors in pots, temperas and mixed media, etc. When mixed with pure water, it gives transparent gels like those of xanthan that can be plasticized by adding a few drops of silicone defoamer. Laponite® (as with all coagulators) must be mixed in the blender with water and incorporated before any surfactant, dispersing or emulsifying agent, otherwise

Laponite RD in powder


295

THE INERT SUBSTRATES Inert substrates or structuring fillers are materials that are added to paint pastes to give them relief and change the properties of paint films. You can add cork, glass flakes, glass beads, sand, granites, micas, alabaster, pulp or pure cellulose, etc. ... I will deal here, the most stable and the most useful.

GLASS FLAKES

There is a whole range of glass flakes, with different grain sizes, ranging from 15 to 600 µm. Their lamellar surfaces make it possible to play with light, in order to obtain very reflective and therefore very interesting paint films.

Glass flakes 600 µm

GLASS POWDER IN BALLS, GLASS MICROSPHERES & GLASS BEADS

Solid glass beads are made with silica. The development of this type of pearl is originally based for its use as a pigment dispersant, formulation of reflective paints, to facilitate the grinding of minerals and as fillers for paper. Matting agent for acrylic paints and for oily varnishes from 1 to 4% of the final paint volume. Size from 50 µm to 0.5 mm. [53]

Glass spheres

CARACTÉRISTIQUES CHIMIQUES

Composant SiO2 dioxyde de silicium PbO oxyde de plomb K2O oxyde de potassium Na2O oxyde de sodium ZnO oxyde de zinc Sb2O3 trioxyde d’antimoine B2O3 sesquioxyde de bore Bao oxyde de baryum Al2O3 oxyde d’aluminium

Pourcentage 61.0 % 24.0 % 10.0 % 3.0 % 1.0 % 0.5 % 0.3 % 0.2 % Traces

Glass microspheres

GRANIT 0,2 - 0,6 mm

Granite is a grainy, fully crystallized igneous rock formed by the slow and deep cooling of magma resulting from the partial melting of the earth's crust. Granite is formed of granular minerals (crystals) all visible to the naked eye, mainly quartz, micas (biotite or muscovite), potassium feldspars (orthoses) and plagioclases. It may also contain hornblende, magnetite, garnet, zircon and apatite. There are all colors. Grey Granit


296

THE INERT SUBSTRATES ACID FREE PAPER PULP

It is 99% pure cellulose. Cellulose is a carbohydrate of Chemical Formula (C6H10O5) n (n between 200 and 14,000), it is the main constituent of plants and in particular of their cell walls. Impasto can be made by mixing paper pulp with all kinds of aqueous binders, such as acrylic or glues. Avoid mixing with the oil, which burns cellulose fibers over time.

DRALON FIBERS ®

It is an acrylic fiber, the most used in outdoor fabrics. This fabric was designed by the company Bayer® on the basis of severe certification tests, both in terms of texture and final treatment. Its advantages are numerous: high resistance to wear, the particular interlacing of the fiber makes it very resistant. Air permeability allowing quick drying. Rot-proof, mold does not affect the fibers of the fabric. It does not shrink, swell, or absorb water. Breathable and anti-condensation, it does not retain heat and allows moisture to evaporate. Dralon® has a high resistance to sunlight, averaging 6 to 7 on a scale of 8 (for comparison, cotton has a resistance of 4 and polyester between 4 and 5). Insensitive to thermal changes. Resistant to chemicals, whether basic or acidic. Dense, insulating, aesthetically superior, the dralon is flexible and pleasant to the touch. Wear a mask when handling these fibers.

acid-free pulp

You can make small papers by mixing paper pulp with a little 10 gram skin glue or a mixture of pure water and Plextol B500 and defoamer in a blender. You can make all kinds of paper in different shapes and thicknesses with wooden molds. The evaporation of water, on the other hand, takes a very long time. Do this in the summer. How to Making the papers would require a an entire book from scratch.

Paper 9 X 14 cm, thickness 2 mm made with paper pulp + Plextol. 1999

Dralon 6 mm

ARBOCEL® BWW 40, BC 200 and BC 1000

Filler based on cellulose fibers. ARBOCEL® is a cellulose additive in powder or fibrous form used as a filler in paints and plasters, but also in varnishes. It is naturally occurring cellulose, insoluble in water (unlike water soluble cellulose ethers). These finer grades are ~ 8 µm in length, averaging 20 µm up to the longest grades with a fiber length of 700 µm. In long fiber grades, these curved fibers have a "felting" effect.


297

THE INERT SUBSTRATES

ARBOCEL

ARBOCEL® cellulose fibers are also used as a substitute for asbestos. Usually 30 to 50% by weight of the asbestos previously used is sufficient. The shorter the average fiber length of the ARBOCEL® range, the smoother the surface of the finished product will be. If solvents are used, add fibers at the end of the mixing process. With cold bituminous mixtures of low to medium viscosity, sedimentation can occur. This can be inhibited by stabilizing agents such as magnesium silicates or pyrogenic silicic acids. It is recommended to introduce ARBOCEL® in the aqueous phase [60]. Insoluble in water and organic solvents. Resistant to acids and dilute bases. Guideline values ​​for temperature exposure: 160 ° C for several days, 180 ° C for about a day, 200 ° C is the thermal exposure limit. Moisture: 6 to 7% - Density ~ 46 g per liter Reinforced thickening - Excellent resistance to sagging even in a hot environment (> 90 ° C) - Good workability - pH: 6 ± 1. [58] Fields of use: plasters based on synthetic resins, silicate paints, lime, cement, paints with structuring effects.

CORK POWDER

Cork is a material found in the bark of some trees, especially that of the cork oak tree. Cork is a product of low density, antistatic, relatively resistant to fire, good thermal, acoustic and vibratory insulator and resistant to water thanks to the suberin which permeates its cells. Suberine is the main constituent of cork from Quercus suber, from the Fagaceae (formerly cupuliferous) family, exploited for its bark which provides the cork. It is used to create textured plasters.

Cork powder

VOLCANO ASH

It is pure, purified and washed volcano ash. It makes it possible to make heat-resistant coatings. It also serves as a filler with silicate binders.

Volcano ash

Alabaster

Color Index PW25 77231 Formula CaSO4 2H2O Alabaster limestone = carbonate lime Gypsum alabaster = gypsum, lime sulphate. Oriental or Moroccan alabaster is a little more reddish.

Alabaster


298

THE INERT SUBSTRATES SILICA

Color Index Pigment White PW 27 77811 This is fossil diatomite, and is 90% anhydrous silica. It is found in many minerals and pigments. There are 3 types of silica: Crystalline silica, amorphous silica and diatomaceous silica. It is a good filler for light pigments, for example English greens, with which you can prepare shades that deposit much more slowly than those obtained with barium sulphate. [129]

Natural pure silica

Silica is incombustible, colorless or white, in tasteless crystals. It is known to occur in 17 crystalline phases and 5 amorphous phases. Amorphous fumed silica is a thicFumed silica or pyrogenic [129] kening and thixotropic agent with a very fine particle size of 5 to 50 nm used to make mediums and gels with oil. Natural silica is used to make floor paints that are very resistant to abrasion and to improve adhesion between paint coats. Always wear gloves and a mask when handling.

fumed silica

Scotchlite™ K1 et S 22

Hollow glass microspheres. Average particle size: 29 µm Maximum size: 53 µm

Chemical description: 97 100% soda lime borosilicate glass with 3 mg / m3 silica dioxide. Hollow glass microspheres, special for coloring and stucco. Average particle size: 46 µm, maximum size: 200 µm for K1. Scotchlite hollow glass spheres are Scotchlite S 22 Hollow Glass Spheres made from boron silicate glass with a low alkali content, which means they can be mixed with cement. Its average volume is 8 l / kg, which is why it is an economical solution for the application of light loads. With 125 g of glass per liter of mortar, the specific weight of the plaster can be reduced to half. This hollow glass is an exceptional insulator against heat. However, due to the low density of the particles they must be handled with great care to prevent them from entering the eyes. It is recommended to protect yourself with tightly sealed safety glasses. These are hollow glass microspheres, special for liquid varnishes or liquid injection mortars. Compatible techniques: Acrylic, Fresco, Cement, Silicate binder, Ceramic [53].

Cristobalite and Cristobalite Sand

Cristobalite is a mineral composed of silicon dioxide. Chemical Formula: SiO2 with traces of Fe, Ca, Al, K, Na, Ti, Mn, Mg, P. Cristobalite is very stable as a filler since it consists of silica. Wear a mask when handling in its powder form. Compatible techniques: Oil, Acrylic, Fresco, Cement, Ceramic. Cristobalite 8 µm


299

THE INERT SUBSTRATES Granites [54]

Granite is a plutonic rock found throughout the Earth's continental crust, most commonly in mountainous areas. It consists of coarse grains of quartz (10-50%), potassium feldspar and sodium feldspar. These minerals represent more than 80% of the rock. Other common minerals are present such as mica (muscovite and biotite) and amphibole. The chemical composition of granite is typically 7077% silica, 11-13% alumina, 3-5% potassium oxide, 3-5% soda, 1% lime and 2-3% total iron and less than 1% magnesia and titanium oxide. Volcanic rocks of mineralogical composition are called rhyolite, volcanic equivalent of granite. Granites are the most abundant plutonic rocks in mountain ranges and continental shield areas. They occur in large batholiths that can occupy thousands of square kilometers and are generally closely associated with quartz monzonite, granodiorite, diorite and gabbro. Many ore deposits (eg copper, lead, zinc, gold and silver) are produced by hydrothermal solutions created during the late stages of cooling of granite compounds. These can be set up around peripheries or linked to cracks and fractures within granite ~ 27% quartz + mica, amphibole, pyroxene, and feldspar albite, a building stone. Granite comes in different shades, ranging from gray to yellow to pale red. Compatible techniques: Oil, Acrylic, Fresco, Cement, Ceramic. Ground they lose beauty, we preferably sprinkle them on fresh binder.

The Fuchsite

Color Index Pigment White PW 20 77019 that of mica. Chemical Formula: K (Al, Cr) 3Si3O10 (OH) 2 It can contain up to 6% Cr2O3 chromium Fuschite is a variety of green mica that is mainly found in Brazil, but it is also found in Russia and India. It was named after the German mineralogist Johann Fuchs. Fuchsite crystallizes in the monoclinic crystal system. It is found in phyllites and schists, in metamorphic rocks with green schist facies. In most cases, it occurs as tiny grains scattered throughout the mass of rock, but sometimes the rock is made up almost entirely of fuchsite.These fuchsite-rich green rocks are known as "verdite." The common shade of the mineral is pale green to emerald green depending on the amount of chromium substitution. Mica crystals are flexible and slightly breakable with a hardness of 2 to 2.5 on the Mohs scale. The fuchsite may be fluorescent green. The radioactivity of fuchsite is due to its potassium (K), it is barely detectable. A bright green variety of muscovite having chromium in place of part of aluminum differs from most other muscovites having varying amounts of substitution of trivalent chromium in the mineral. Muscovite begins to take on a very light green tint with the substitution of a small amount of chromium by aluminum. As the amount of chromium increases, the green undertone becomes stronger and varies from a rich emerald green where chromium is present in abundance to a very clear sea green. Compatible techniques: Oil, Acrylic, Tempera, Waterbased paint, Fresco, Cement, Ceramic, Silicate binder.

2

1

Grey Granite

Yellow Granite

Pink Granite

3 Fuchsite green quartz mica 3 grainings: (1) 100 µm fine, (2) 500 µm and (3) coarse


300

THE PREPARATION AND THE COOKING OF OILS

In order to accelerate their hardening, the oils are cooked in the presence of substances, siccatives such as litharge, manganese acetate or copper acetate, etc. Strictly speaking, there is no drying of the oil, but hardening of the oil with an increase in its weight and volume, this reaction is called "oxidation". it is the oxygen in the air that allows the oil to harden. The formation of hydroperoxides is observed while the double bonds are retained. The oxidation mechanism is explained by a radical reaction - (called a reaction in which free radicals intervene) - involving the tearing of an allylic hydrogen atom by a free radical. In fact, oils contain easily oxidizable impurities, such as hydroperoxides formed during manufacturing processes. The radicals (noted X) resulting from the thermal decomposition of these impurities or generated on contact with the atmosphere can tear a hydrogen atom from the fatty acid chain and initiate a radical oxidation reaction. Dryers are oxidation catalysts in powder or liquid form, they are added to oil in a saucepan set on a medium heat fire. Litharge is one of the best siccatives for making a socalled "clear" oil (or "black" if it is cooked more strongly with only walnut oil), because it allows oil paints to harden through the core. and the realization of the famous "Mastic gel medium" that Rubens used from 1620 and that Jacques Maroger describes on page 154 of his book. It should be noted that the prepolymerization of the oil allows some precipitation of impurities, low temperatures up to 100 ° C give the best qualities, high temperatures up to 260°C obscure the oils.

Recipe for clear oil N ° 1A or black oil

1/2 liter of Poppy seed oil and 1/2 liter of walnut oil or 1 liter of pure walnut oil to make black oil 60 grams of litharge 1 onion, peeled then cut in half Mix the litharge with a little raw oil at the bottom of the container, then add the rest of the oil. Add the 2 onion halves and cook until the onion is cooked, it should be fried and have a caramelized color. Usually after 2 hours the clear oil is ready, there is no precise time, it all depends on the heat to which the cooking is performed. The oil should hardly simmer and it should never boil, the ideal temperature ranges from 85 to 110 ° C, although I personally avoid going above 95 ° C for a very clear oil. Depending on whether I use a mixture of Poppy seed oil and walnut oil or pure walnut oil, I call this oil, light oil or black oil. The clear oil is made with poppy oil mixed with walnut oil while the black oil is made with pure walnut oil cooked a little hotter at 110°C.

Litharge deposited at the bottom of a saucepan

Walnut oil

Poppy seed oil

Freshly made clear oil sedimentation with a mixture of equal parts of walnut oil and Poppy seed oil.

In the middle, clear oil after 2 years of sedimentation. In the bottle right and left, having poured oil into a new bottle and have it in the sun for 1 year.

Clear oil No. 1 a has very good film-forming qualities, black oil is smoother under the brush, this is the only difference between these two oils.


CLEAR OIL PREPARATION N°1A

COOKING IN DETAIL OF OIL WITH LITHARGE

onion

1 After putting the litharge and oil, add the peeled onion, cut in half then mix everything, cooking can begin

5

Cooking after 1 hour 15, put the heat to 85 ° C without stirring

6

Cooking after 1 hour 30 minutes, cook for 15 minutes at 90 ° C and stir gently all the time

onion

2

Cook for 30 minutes, stir gently all the time with a round brush (2 cm in diameter) to prevent the litharge from remaining at the bottom

3

7

Cooking after 45 minutes, cook for 15 minutes without stirring maintain heat at 90 ° C.

Cooking after 1 hour 45, put at 85 ° C for 15 min, do not stir

Electronic thermometer

4

Cooking after 1 hour. Increase the heat to 95 ° C for 15 minutes, stirring occasionally.

8

Cooking after 2 hours: cook at 90 ° C the last 15 minutes do not stir. That makes a total of 2 hours 15 minutes.

301


302

OTHER SICCATIVE OIL RECIPES I use Poppy seed oil to make very clear litharged oils. It is possible, if desired, to mix these two oils during cooking to produce mixed paints and emulsions. It only remains to transfer the lukewarm oil into a bottle of more than one liter or filter this oil when it is lukewarm by means of a coffee filter and a funnel and then let the oil settle. For many months, the oil that floats is collected. Always leave a gap of 5 cm between the oil and the cap of the container (the first years) because it increases in volume the first year up to 10% of its weight and the second year up to 8%. Ideally, the oil should be allowed to settle for 2 years. The use of walnut oil in artistic painting dates back much further than that of linseed oil. When 15th century artists began adding oil to their tempera paintings, it was walnut oil that they used.

Jan Van Eyck in Flanders and Antonello da Messina in Italy both knew the properties of the oil and how to use it. From then on it was widely used by the great Masters, the question being who did not use it rather than yes. The systematic denigration of walnut oil and its modest use by art paint suppliers is due to the fact that it costs 10 times more than other oils. A liter of pure, high-quality walnut oil can be worth up to € 250 per liter, while flaxseed or carnation oil is up to € 25.

Spanish Oil Recipe (Velásquez oil)

1 liter of poppyseed oil or walnut 50 grams of acetate or copper octoate, or copper that has macerated in vinegar for 15 days. 1 onion, halved This very fine oil only needs to be decanted, unfiltered, and when hardened, it presents itself as a film of frozen oil in a very beautiful shade of green. Spanish oil is used copper acetate with blues and greens, with which it gives very beautiful, very subtle glazes; moreover, it has very good drying power. This oil is made like clear oil. The drying oils are made according to the same procedure, only the ingredients and the proportions change.

Grapeseed oil recipe cooked with manganese acetate

Manganese acetate is an oxidation catalyst (like copper acetate), of Chemical Formula: Mn (C2H3O2) 2.4H2O. It is in the form of pale pink crystals. It is reduced to a fine powder and then added to the hot oil. Grapeseed oil is resistant to high heat, it allows for very clear binders, it is necessary to leave to settle until the oil becomes clear again, this sometimes requires more than 6 months to wait. The oil is warmed to make it easier to filter through a coffee filter. If the oil is too dark, you can lighten it by mixing 1 liter of cooked oil, but you can also purify the raw oil before cooking 50 grams of Attapulgite Shake vigorously, then filter again or allow to settle.

We make the drying oil by cooking 1 liter of grapeseed oil

Equipment for bottling oils

50 grams of manganese octoate or acetate 1 onion, halved You will find grape seed oil at "à l'olivier" in Paris or on the internet. See suppliers Pay attention to the harmfulness and toxicity of siccatives in lead, copper or any other drier. Wear gloves and a mask and if you can cook your oils outdoors, otherwise open wide the windows of your workshop or the place where you cook your oils. The odor given off is not toxic, but be careful not to burn the oils, as the smoke is very harmful and poisonous.


303

OIL PURIFICATION There are several methods of purifying oils before and after cooking.

Purification of raw oil with acid

Purification is performed using hydrochloric or sulfuric acid. 1. Stir in 1.5% to 3% sulfuric acid at 66 ° B or hydrochloric acid very slowly. Beat the oil-acid mixture for 15 minutes, it turns khaki green .... then leave to stand for 20 minutes. 2.Add 20% water at 40 ° C and beat the oil again for 15 min to allow the water to absorb the acid. 3. Purge the water and check the pH. If it remains acidic, add a little lime to absorb the remaining acidity. 4.Filter through chalk and then fine sand or even better activated charcoal, over which the oil is passed at 60/70 ° C to fluidify it. There is a strong filtration trick with a sheet of paper towel rolled up and introduced into the tube of a funnel lengthwise, i.e. over 6 centimeters, a simple sheet of paper towel gives normal filtration, even coarse, but placing it in this way gives a much more effective filtration, it is also possible to add a little sand on top of the paper towel to achieve even more efficient filtration. It mimics the action of helical filtration glassware with activated carbon inside the tube and is just as effective. Fontainebleau sand

Sheet of paper towel

Purification of raw oil with water and salt There is a recipe for purifying and lightening the oil with water and salt, by mixing 100 g of salt and 50% of water per liter of oil, we shake, we leave to act for 24 hours, we change the salt and the water, we repeat this process 5 times, finally we recover the oil which floats by removing as much water as possible and allowing the remainder of the aqueous liquid to evaporate or by putting the oil in the water. freezer to recover it since it has thickened, the water having remained liquid or having frozen depending on the time left in the freezer. Otherwise the easiest way is to use a plastic bottle then we make a hole with a straw just above the sediment of impurities, and we recover the oil in another container by decanting, this avoids having to freeze oil and water and this is very fast. Finally, we expose to the sun for several months, this raw oil which will become clearer. Purification of linseed oil by salt In the photos, you will notice the impurities on the surface of the water and salt sediment. After removing the sediment, add water and salt, shake vigorously every 2 hours over 24 hours, at the end the impurities are well separated from the rest of the oil. By repeating this recipe 5 times, we are able to naturally purify and oxygenate our oil. You have to be careful not to take this thick layer of impurities. natural purification of linseed oil with salt and water. The easiest way is to use a plastic bottle. 2016

Alkaline refining of raw oil

With alkaline refining, a very clean oil is obtained, but which has poor pigment wetting properties. These oils often require the use of additives for the satisfactory preparation of paints. Currently, almost all oils are obtained from heated seeds or from meal using solvent extraction followed by alkaline refining. Linseed oil coming out of the freezer

Oil recover from the left flask

natural purification of linseed oil with salt 2016


304

CLARIFICATION OF OILS Filtration and Purification of raw oils

Attapulgite and Bentonite are used to purify and lighten raw non-drying oils by retaining various impurities in their mass, thus making them clearer.

Recipe for lightening the oil

25 to 50 grams of attapulgite in 1 liter of raw oil Shake vigorously every 2 hours over 12 hours and leave to act for 24 hours. The oil is warmed to filter it or to allow the oil to settle. Recipe for absorbing impurities in oil 25 to 50 grams of Bentonite 1 liter of raw oil The liquid is stirred vigorously, left to act for 2 days then reheated and filtered through a coffee filter or silk stocking or allowed to settle. What clarifies the oils above all else is the discoloration of the particles by the action of UV rays from the sun. You have to expose the oil for about 18 months to UVA for it to become clear, or 18 months of discontinuous daylight and as such why can we lighten the oil all year round.

Ultraviolet A and B rays

There are two types of UV rays that reach the earth, UVA from the sun and UVB. UVB rays are the shortest rays, and for this reason they reach the earth only when it is tilted closest to the sun. This is why summers are hotter. The earth faces the sun and UV rays that are short are much more intense because they reach the earth's surface more easily. UVB rays do not penetrate the deep skin of the skin, so they only affect our outer skin causing tanning and burning of the skin. When the earth rotates and tilts away from the sun, we experience winter and therefore UVB rays are less intense, so some of them barely reach the earth's surface. That's why you can't really get a tan under a winter sun. UVA rays are the longest rays of the sun. This means that they reach the earth no matter how steep it is. UVA rays continuously cover the entire surface of the Earth wherever "daylight" can be seen. Who says sunlight, says UVA rays. UVA rays do not get weaker during winter, although sunlight does get weaker during this season. UVA rays are the same intensities in June as in December. They have the same strength in the Sahara as in Paris. Because UVA rays have a longer wavelength, they are able to penetrate deeper into objects. As a result, UVA rays will penetrate more glass bottles and vials.

So UVA rays cause dangerous side effects inherent to their strengths and lengths. UVA rays that have been tested by scientists are able to penetrate glass and clothing. So, a common cotton garment that can block UVB rays is almost "transparent" to UVA filtering. Personally, I only get exposure in the sunny months for 2-3 years in a row, there is no avoiding it. It is necessary to put the raw or cooked oil in bottles if possible not very thick so that the rays of the sun reach the oil as much as possible, then place these glass bottles on airtight trays in case one of the bottles should come to break or explode, this in order not to lose the oil, you can if you want at the same time to thicken and dry naturally the oil, removing the plugs and leaving the oil to deal with oxygen of air for 3 months.

In 1 phase, you can perform 5 operations :

1. Oil Sedimentation. 2. Clarification of the oil thanks to UVA rays 3. Purification, the result of sedimentation and clarification. 4. Oil thickening. 5. The slight siccativation of the oil was due to radical reactions, a very slow complex phenomenon of oxidation and the unsaturation of fatty acids contained in the oil. In the presence of oxygen in the air, hydroperoxides are formed and covalent bonds are established between fatty acid chains (crosslinking). In light of these facts, we understand the price of "oleum crassum" walnut oil at ~ € 249 per liter.

Clear oil N ° 1A after 2 Clear oil N ° 1A transferred Black oil N ° 1 after 2 years of years of sedimentation into 1 new bottle and then sedimentation then exposed then exposed to the sun exposed to UVA rays for 1 year to the sun for 1 year

Unretouched photos, just cut out, taken in October 2016


OILS YELLOWING AND AGING Why you should avoid exposing oil paintings in direct sunlight

The yellowing of oil paints is affected by the pigment, the binder, the solvent and the drying agent used. To understand the mechanisms, which occur during the aging of the oil during exposure to light, it is necessary to highlight evolutionary mechanisms called "Auto-oxidations" and "Photo-oxidations". Oxygen, a molecule essential to life, is capable of causing damaging effects on materials through the formation of free radicals and activated oxygen species (EOA). Light in the presence of oxygen promotes the oxidation of unsaturated fatty acids. Ultraviolet rays break down hydroperoxides, peroxides, carbonyls and oxygen-containing compounds, producing radicals that initiate auto-oxidation. The chain reaction is initiated by abstracting an allylic hydrogen atom to give an allylic radical stabilized by delocalization on three or more carbons. The initiator is a free radical produced by the decomposition of hydroperoxides present or already produced by photo-oxidation. Thermal decomposition can be promoted by varying traces of metal ions. [95] Auto-oxidation is characterized by an induction period (process of oxygen consumption) during which the concentration of free radicals increases until the stages of autocatalytic propagation become dominant. Near UV or visible light wavelength photo-oxidation requires a sensitizer. Pigments are naturally present in oils such as chlorophyll, hematoporphyrin and riboflavin acting as sensitizers, as are dyes, such as erythrosine and methylene blue, etc.. All organic materials have dyes in them. The light excites these sensitizers which give their coloring to all organic materials. A solid film of oil paint is formed by crosslinking between fatty acid chains which can be of three types : 1. CC 2. An ether 3. Peroxides. Many oxidation products formed from the decomposition of hydroperoxides are identified and consist of alcohols, ketones, aldehydes, epoxides, esters. Oxidation of the oil leads to the formation of C-C crosslinks, producing peroxide bonds (peroxide radicals [ROO •]), compounds with a greater amount of oxygen than a normal oxide. The curing step is considered "oxidative polymerization", which results in a three-dimensional network. When this polymerization comes to an end, a "steady state" is said to be reached. Oil changes through the breakdown of its ethers, C-Cs, and / or peroxides present in the dry oil film.

305

These degradation reactions can explain the formation of most low molecular weight oxidation products and are identified by basic analysis on oil paints dating back several years or even centuries. The newer the paint film, the more monounsaturated fatty acid and less diacids it contains compared to older paints. This means that the oxidation process continues in paints over several hundred years. Unsaturated and oxidized fatty acids lead to the greatest amount of diacids in old paints. Analyzes of oil films dating back 5 years show short chain fatty acids (C7-C10), diacids (C7-C11), long chain saturated fatty acids (C16-C18, C20-C22), a cyclic fatty acid at C18 and certain unsaturated fatty acids oxidized at C18. [96] The linoleate chain consists mainly of carboxylic acids. The oscillation of the ester-linking carbonyl group of triglycerides decreases during photo-oxidation. The photodegradation of triglycerides of ester bonds in aliphatic polyesters is quite stable in photo-oxidation at λ> 300 nm. [96]. However, in the triglycerides that make up the oil, there is a site with a tertiary carbon atom in the α position of the oxygen atom. As can be true for most of the previous reactions, radical attack is then likely to occur. With photo-oxidation, the cured oil film demonstrates UV absorption in short wavelengths. This result indicates a rapid decomposition by oxidation of contaminants in oils, due to their high photosensitivity. In summary, we can say that the oil ages by the effects of auto-oxidation, polymerization and photodegradation due to oxygen and oxidative stress (radical attack). The thermostability of drying oils is clearly demonstrated in the literature. By thermal oxidation, no change in the chemical structure of the hardened oil film is noticed. This finding, considering the condition of the paintings that date back several centuries, is not surprising. After all that has just been exposed, it is important to know that oil paintings should never be exposed to direct sunlight "for long periods", in order to reduce their yellowing. because the result causes rapid damage to the paint films, due to numerous modifications generated by the phenomenon of photo-oxidation. It is preferable to expose raw oils before firing, so the lightening is durable and less detrimental to the painted works.


306

THE DIFFERENT DRYING OILS AND FATTY ACIDS IN OILS

Raw walnut oil

Poppy oil

Raw linseed oil

2 black oils 2 years

Clear oil 2 months

Black oil

Linseed oil over a brisk heat

Sedimentation of clear oils after 2 weeks

Clear oil 18 months

Clear oil 2 years + 1 year exposure to UVA

Black oil 18 months

Black oil 2 years

This oil, cooked between 120 and 160°C over 2 hours without drying at the start (so as not to get intoxicated) is perfectly resistant to humidity once hardened. It is enough to conduct the cooking like clear oil by raising the temperatures by 120°C for 15 minutes then raising to 160°C for 30 minutes, when the oil smokes drop to 95°C, let the oil cool down to 40°C, then add 60 g/l of litharge off the heat and cook for 1 hour at 95°C. Leave to settle for 6 months then use the oil to paint very oil cooked over resistant to humidity. a brisk heat

FATTY ACIDS IN OILS Number of carbons

Name of acid

Chemical Formula

C4 : 0

butyric acid

CH3 (CH2) 2CO2H

C5 : 0

valeric acid

H3C- (CH2)3-COOH

C6 : 0

caproic acid

CH3 (CH2) 4CO2H

C7 : 0

enanthic acid

H3C- (CH2)5-COOH

C8 : 0

caprylic acid

CH3 (CH2) 6CO2H

C9 : 0

pelargonic acid

H3C- (CH2)7-COOH

10 : 0

capric acid

CH3 (CH2) 8CO2H

C12 : 0

lauric acid

CH3 (CH2) 10CO2H

C14 : 0

myristic acid

CH3 (CH2) 12CO2H

C16 : 0

palmitic acid

CH3 (CH2) 14CO2H

C18 : 0

stearic acid

CH3 (CH2) 16CO2H

C18 : 1 9c C18 : 2 9c12c C18 : 3 9c12c15c C22 : 1 13c 20 : 5 5c 8c11c14c17c 22 : 6 4c7c10c13c16c19c

oleic acid linoleic acid α-linolenic acid

CH3 (CH2) 7CH = CH (CH2) 7CO2H CH3 (CH2) 4 (CH = CHCH2) 2 (CH2) 6CO2H CH3CH2 (CH = CHCH2) 3 (CH2) 6CO2H

erucic acid

CH3 (CH2) 7CH = CH (CH2) 11CO2H

arachidic acid

CH3CH2(CH= CHCH2)5(CH2)2CO2H

behenic acid

CH3CH2(CH= CHCH2)6CH2CO2H

There are over 1000 fatty acids, but only 20 or less in sufficiently large amounts in oils and fats (above). C16 to C18 fatty acids are the most common.


307

RESULT OF OILS SEDIMENTATION On the left 3 clear oils just cooked, put to sediment in September 2013. On the right 1 black oil left has sedimented 2 years.

+ 2 years of sedimentation + decanted + 1 year of exposure to UVA

Black oil n ° 1, before and after having transferred the oil, note on the right the remainder of lead stuck to the walls of the glass, this phenomenon of "horizontal sedimentation" only appears when the vertical sedimentation is completed and that one transfers the oil to a new glass bottle. This purifies the oil naturally and makes it possible to obtain translucent binders of very high quality, containing the right proportion of siccative. This allows for lighter Rubens and Venetian mediums to be made.

A phenomenon of "horizontal sedimentation" of the lead from the black oil on the glass walls, this only appears after two years of vertical sedimentation. From this moment, by pouring the oil into a new bottle as below and then exposing it to the sun for 1 year, it will become much clearer without losing its drying force.

Oil decanted

Clear oil N ° 1 after 2 years of sedimentation and 1 year of exposure to UVA

horizontal sedimentation

2 black oils N ° 1 sedimented: the one on the left is finished, you just have to expose it to light. The oil on the right must be transferred and then exposed to UVA rays for 1 year.


308

MARBLE & WHEELS TO GRIND PAINTS

Frosted glass plates dull very quickly and are much less effective than a real marble in serpentine, porphyry or other varieties (the ideal would be to have a white marble and a black marble), knowing that if the frosted glass plate becomes dull and the wheel remains frosted, the pigments will be less well ground, not to mention that it is necessary to press strongly, while the weight of the granite wheel is more substantial and therefore requires less effort ... I use glass as a palette and the glass wheels only for mixing paints and dyes which require less shear force.

Pocket marble 40 X 30 cm 1 cm thick

Preparation of a new 160 cm X 55 cm marble with pumice stone: it must be matt after treatment. Swedish black granite wheel Height 20 cm, 10 cm Ø at the base: ask a marble worker to make a wheel the size of your hand and your strength, because it is very heavy! Black marble 95 X 32 cm and granite grinding wheel You will find marble, one white and one black, at a marble worker

Light marble for very dark pigments 45 X 48 cm


LIST OF OIL ABSORPTION RATES OF PIGMENTS • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • •

Annaline ~ 18 to 22% Azurite ~ 26% Barite white ~ 15 to 20% Lead white ~ 13% Titanium White ~ 18 to 22% Natural Titanium White ~ 30% Zinc White ~ 20% Zirconium white ~ 18 to 22% Cerulean Blue ~ 15-25 Cobalt blue ~ 20 to 30% Blue Heliogenic ~ 40 to 50% Indanthrene blue ~ 37% Maya Blue ~ 65% Manganese Blue ~ 30% Prussian blue ~ 35% Egyptian Blue ~ 22% Ultramarine blue ~ 31.6% Phthalocyanine Blue ~ 35-78% Iron-Zinc Brown PY 119 ~ 20% Manganese brown PBr 8 ~ 18.6% Cochineal carmine ~ 70% Cinnabar ~ 13 to 16% Natural chalk ~ 10 to 20% Precipitated chalk ~ 30 to 60% Dolomite ~ 15% Epidote ~ 20 to 30% Madder ~ 80% Goethitis ~ 18 to 30% Glauconite ~> 70% Manganese Gray ~ 34% Spinel Gray ~ 48% Gypsum ~ 30% Hematite ~ 18 to 30% Aluminum hydroxide ~ 30 to 70% Indigo ~ 30% Jarosite ~ 55.8% Barium yellow ~ 27% Bismuth yellow ~ 25% Cadmium yellow ~ 20% Chrome yellow ~ 15 to 20% Indian yellow imitation PY 150 ~ 55% Irgazin® yellow greenish ~ 60% Isoindole yellow ~ 60-65% Cobalt yellow ~ 20% Hansa Yellow Gloss PY 74 ~ 110% Hansa Yellow Reddish PY 3 ~ 35% March yellow ~ 54% Naples yellow ~ 15 to 20% Lead yellow tin ~ 15 to 25% Pyramid Yellow ~ 55% Nickel titanium yellow ~ 14 to 18% Zinc yellow ~ 20% Praseodymium yellow ~ 36 to 38% Priderite yellow ~ 22 to 27% Strontian yellow ~ 20% Kaolin ~ 25 to 50% depending on the variety Lapis-Lazuli ~ 36% Limonite ~ 30 to 35% Lithopone ~ 15 to 20% depending on the variety Black magnetite ~ 15%

• • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • •

Malachite ~ 34% Trimmer ~ 10% Mica ~ 56 to 74% depending on variety Minium and Orange Mine ~ 10% Smoke Black ~ 80 to 100% Lamp black ~ 80 to 100% Manganese black ~ 25 to 30% Spinel Black Mn-Fe PBk26 ~ 48% Spinel black Cu-Mn-Fe PBk26 ~ 20% Spinel Black Cu-Cr PBk28 ~ 20% Spinel Black Fe-Mn PBk33 ~ 16% Black vine ~ 50 to 60% Ivory black ~ 50% Black Bones ~ 60% Iron oxide black ~ 15 to 25% Carpathian Golden Ocher ~ 60% Very light French ocher ~ 40% Yellow ocher ~ 30 to 35% Pale Cyprus Ocher ~ 54% Red Ocher ~ 25% Glazed orange ~ 15 to 25% Orange Irgazin® DPP-RA ~ 40 to 60% Isoindole orange ~ 50 to 60% Molybdenum Orange ~ 20 to 30% Paliotol® Orange ~ 95% Titanium Orange ~ 25% Orpiment ~ 60 to 70% Yellow oxide gamma ~ 54% Hostaperm Pink E ~ 100% Scarlet Azoic Red ~ 60% Cadmium red ~ 20% Irgazin® DPP BO red ~ 72% Molybdenum red ~ 20 to 30% Pozzuoli red ~ 20 to 25% Sanitobre ~ 44% Smalt ~ 25% Silica ~ 23 to 33% Talc ~ 25 to 55% depending on the variety Sienna ~ 80% Burnt Sienna ~ 60% Charred Umber ~ 35 to 45% Natural Shadow Land ~ up to 50% Green earth ~ up to 80% Green Earth of Verona ~ 48% Vermilion ~ 13 to 16% Chrome Green Black Hematite PG17Blk ~ 9% Cobalt green ~ 20% Cobalt Green Titanium Spinel ~ 16 to 22% Egyptian Green ~ 22% Green says "Veronese" ~ 20 to 30% Heliogenic bluish green ~ 40 to 50% Yellowish Heliogenic Green ~ 60 to 70% Zinc Green 30 to 35% Emerald green ~ 90% Chromium Oxide Green ~ 53% Victoria Green ~ 35% Cobalt violet ~ 47% Manganese violet ~ 25% March purple ~ 15 to 20% Ultramarine violet ~ 50% Volkonskoye ~ 45 to 50%

309


310

AQUEOUS GRINDING TO MAKE ALL THE PAINTS Always check the pH of your Wet the pigment with wawater and adjuvants before ter to spread it in a thin layer mixing them with pigments then add 3 drops of glycerin or honey to facilitate grinding, so the wheel slides better and grinds easier.

1

Make 8s in the shape of horizontal infinity, to grind the pigment into a watery mass.A marble that is longer than it is wide is ideal for making large 8s, as they are more effective than O's and S's, I discovered in 2018 that they allow to obtain a particular angle and thus to grind much more efficiently. The water then evaporates, it is here only a vehicle, a means, it will be necessary to add a binder to constitute a real paint at the very end of the grinding, this makes it possible not to burn the binder of the painting.

Hold the wheel in the middle with one hand to drive it and one on the top to hold it vertically: the weight of the wheel is enough to grind the material, no need to push vertically with the fine pigments (in the case of minerals it's the contrary). Reserve the paste at the end of the marble: scrape at an angle of 60 °, then grind an ultra thin layer each time, for 30 g this requires 10 times 3 g depending on the size of the marble.

3

You must try to make a layer as thin as possible: if it is too thick, remove a strip of dough in the middle or on the sides with a wide knife

2

Grind one thin layer at a time: To make a palette of 48 shades in 30 ml, it takes about 10 minutes per shade, i.e. 8 hours of grinding: see page 316. 4

and continue the grinding which will naturally spread the aqueous dough on the entire surface of the marble.

5 It is necessary to grind a thin layer each time to achieve a very fine reduction of all of the pigment in the form of an aqueous paste. The natural inorganic pigments are the most difficult to grind, because their aggregates which are formed during their creation, bind them intimately. The ideal would be to grind as finely as possible, with a vibratory grinder, the dry pigments, but as this device is very expensive, we use the method of grinding on marble with a wheel and water: moreover if we let the water evaporate completely, this allows to obtain a pigment flour of about 5 to 10 µm, which will then allow us to make paints by simply mixing with the binder of our choice and then putting them in a tube .


PAINTS GRINDING

311

TEST TO CHECK IF THE GRINDING IS OPTIMAL The oil uptake or absorption rate is the amount of oil necessary to achieve a stable suspension of pigment and oil to form a paint that has good rheological properties and the right oil / pigment ratio. The absorption rate is calculated using a simple method by multiplying the quantity of oil expressed in milliliters by the density of the binder, i.e. 0.93 for walnut oil, the result is divided by 100 then it is multiplied by 100, we thus obtains a very precise absorption rate. The easiest and fastest way is to weigh the pigment and dose the oil with a millimeter syringe if you want to express the Oil absorption of a pigment directly. This is very practical for wetting, among other things, because from now on it will be enough to weigh the oil and the pigment to obtain a paint paste with the right balance between dry matter / oleaginous binder. Oil absorption is multifactorial, it can vary according to the fineness of the particles of the pigment, take for example a titanium orange PBr 24 which exists in 5 varieties of fineness from 1.1 µm to 2.2 µm from some suppliers; this pigment ground in a paint system will be brighter depending on the fineness of the particles, therefore it requires less oil for its grinding. The phase of the pigment, namely its structure, conditions its Oil absorption, as well as its composition and the weight ratio of its chemical components. Thus, you will be able to notice on the list of the "Rate of Absorption" page 293, not a fixed rate for all the pigments, but often a range of Oil absorption variable for some of them, expressed in percentage of oil for. 100 grams of pigment.

Calculation of the oil absorption rate of the pigments

Or an ultramarine violet which requires for 100 grams of pigment 53 milliliters of oil will have its absorption rate expressed with this formula

A=

x 0.93 [ 53 100 ] X 100= 49,29

Either the Oil absorption of ultramarine violet is 49.29 grams of oil per 100 grams of dry pigment of ultramarine violet, or about 50% of oil. But how do you know if this rate is correct?

Test to check if the oil level is correct and if the grinding is optimal

After wetting and pre-crushing 12 hours before, the pigment with its sufficient weight in oil, start on the marble the grinding of the oleaginous material using the wheel. There is a way to know if the paste is sufficiently supplied with oil and at the same time if it is sufficiently grounded, because there is no point in grinding an oil painting too much, there is a risk of exhausting the paste and burn. Take a round or curved painting knife and put it in the paint paste then apply in the vertical direction a reverse thrust to the work surface and remove it from the paint, a filament will be created at its top which goes lie down in height. This filament should keep its shape and stand more or less vertically if there is the right amount of oil in the dough. In the photo below, we can see that there is a little extra oil, because the filament must remain vertical and not be bent as is the case here. In this case, add a little dry pigment, let it soak up and finish grinding the paint.

Mixing pigments with oil results in paints, but to be of good quality, they need to contain the right amount of oil, neither too much nor too little. The weight of the oil is determined by multiplying the volume of the oil by its density (0.93 g / ml). The rate of oil absorption is calculated by the amount of grams of oil used per 100 g of pigment. This method, known as "Gardner-Coleman", expresses the rate of oil absorption or "Oil absorption" which is different for each pigment. This rate is calculated using a simple formula :

A=

[

M x 0.93 P

] X 100

A stands for Oil absorption, it is expressed in grams of oil per 100 g of pigment and is calculated as follows: M stands for milliliter of oil used, P is the amount of pigment used in grams and 0.93 is a constant which represents the density of pure walnut oil here or 0.92 for linseed oil.

yellow ocher Oil-grounded here : Testing the paint paste to see if the grinding is optimal and if the amount of oil is sufficient.


312

THE GRINDING OF OIL PIGMENTS

FROM PIGMENT WETTING TO PUT IN TUBE Grinding oil paints requires little time once the pigment is wetted. 1. Apply the dry pigment to the marble and then soak it in oil. 2. Using a knife, mix the oil and pigment together to make a firm paste. 3. Grind using the wheel, making 8-shaped circles in order to bond the oil with the pigment. It is left to stand for 12 hours, this is called spreading wetting.

that we collect and that we put with the other pile of previously crushed paint . And so on until all the paint has been crushed. We check with the flat of a knife that the material does not squeak, if so, the paint is well ground and ready to be put in a tube. It is possible at this stage to also check the covering power of the paint with the flat of the knife by making a strip as thin as possible which must cover the marble.

4

1

Titanium Nickel Yellow Intense Manganese Brown

Spread the paint paste on one side of an acetate sheet, then roll it up on itself to tube. (see details on page 299)

2

5

You can put the paint in a jar, but I find it unnecessary to waste pigment. Once the 12 hours have elapsed, the actual grinding begins. 4.We make with the wheel on the marble concentric circles in the shape of 8 and S in order to intimately bond the oil with the pigment and to form a ductile paste having the appearance

Cobalt Violet

Creation of an adhesive label to recognize the color of the paint in the tube. Let it harden and then stick there on the tube.

6 3

Manganese Brown

Application of the label in order to see what tint is in the tube. also write the reference of the pigment used. Sartorius Red

of butter, on 1 to 2 mm, as on the photo in 4. All the excess dough is expelled on the sides. We collect the crushed paint in the center that we put in a corner, then we start again with a knob of paste that we crush,

7

Cobalt Blue Turquoise in Oil


313

GRINDING OF NATURAL MALACHITE IN OIL

Natural malachite block

1

Pre-grind the pigment and let it soak in the oil for 12 hours.

Malachite pigment

3

2

Coarsely grind the paint and then let the wetting operate for another 12 hours. Re-grinding is sometimes necessary with some minerals harder than others.

4

To make a 150 ml tube of oil paint, starting from the pigment powder, it takes two hours of intense manual grinding to form an extra fine quality paint, then it is put into a tube.

5

Tube of natural malachite ground in oil 2016

Fine grinding of malachite: grind some, finely, on the marble and lay out the remaining unground paint on the sides, and so on until all the paint is ground. Malachite is very hard to grind, it has a rubbery structure under the wheel and to very finely reduce the grains of the pigment it is necessary to use great shearing forces ; But its shade is so beautiful that it is worth it. Once all of the paint is finely ground, it can be placed on an acetate sheet to tube.


314

EMPTY TUBES AND SMALL GLASS JARS

Pure pigments and dyes ground in water on marble using the method on page 312. For a palette of 48 original shades, it took me 8 hours: I placed the paint pastes in small 30 ml jars. and 130 ml, I would add the binder by simply mixing with a brush in a porcelain cup when painting, so there is no risk of loss if the binder were to harden or chemically evolve and so I can mix them with any binder of my choice, both oil, wax or gum. We could have added a binder and then put the paints in tubes, but I find the glass jars very practical, because you can see the color of the pigments through. Add 2 drops of honey or glycerin + a little camphorated water with the pigment paste, allows to keep a wet side for a very long time.

CAPACITY OF EMPTY TUBES Approximate capacity of empty tubes expressed in grams of medium density pigment.

From bottom to top: white of egg shells, azurite, indigo, malachite, weld, fern and buckthorn

Empty tubes of 200 ml, 120 ml, 95 ml and 32 ml

1 Tube of 12 ml

<20 g

1 Tube of 20 ml

~ 25 to 30 g

1 Tube of 32 ml

~ 30 to 40 g

1 Tube of 50 ml

~ 40 to 50 g

1 Tube of 60 ml

~ 60 to 70 g

1 Tube of 95 ml

~ 80 to 100 g

1 Tube of 150 ml

~ 120 to 150 g

1 Tube of 200 ml

~ 150 to 200 g

Wood log for filling the tubes

The gray strip is used to make the tubes waterproof to a certain extent, but I also add an adhesive strip around the tube to complete the seal. 4 sizes of empty tubes, there are also tubes of 50 and 20 ml, but I do not use them, the tubes of 90 and 32 ml allow to deal with all situations, such as the expression "who can the most, can it less"


TUBING GROUNDED PAINTINGS

315

Take an acetate sheet

Tubing of grounded paint pastes

1

To tube crushed paints in both oil and water, there is a method, a trick, I should say since few artists use it, even professionals who give lessons do not know do not or do not apply this technique and yet it is well known and diffused in the specialized literature. Many artists continue to put paint with a palette knife through the bottom of the tube, what a waste! It's like instead of using a funnel, we use a dropper to pour a liter of water from one bottle to another. It is above all a clean and healthy method with toxic pigments. Once again, let's keep it simple, take an acetate sheet We put the paint on this edge (1) or, failing that, photo paper or any sheet provided that it is not absorbent, at least 21 cm by 15 cm. At the end all along the widest side, the ground paint paste is placed in proportion to the capacity of the tube to be filled. The acetate sheet filled with paint is rolled into a cylinder Then we roll the sheet loaded with the paint paste (2), and then introduced into the tube for 3 cm as if we wanted to roll a cigarette, but a little less than the circumference of the tube, so that the cylinder en- 2 ters just at the bottom of it (side reverse of the plug!). Remember to unscrew the cap and pierce the tube cap (3). It only remains to roll a log on the paint cylinder in order to bring the material into the empty tube, by introducing it over 3 centimeters, 4 maximum and with a small log (4) that we rolls on the sheet in order to drive the paint into the tube, all the material fills the vacuum, we stop when a little material comes out from the side of the stopper. 3 Leave two to three centimeters of space on the fill side of the tube to fold the tube tightly. Perforate the lid of the tube before filling it The tube is then full and free of air bubbles, but you can tap the tube vertically on the cap side to make sure that the paint fills the entire tube up to 2 cm or even 3 cm at least from the inside edge of the tube. here to be able to bend the extremity. We have a paint tube filled cleanly, easily and quickly with no waste. It is advisable to write on a piece of self-adhesive label the name of the ground pigment, its Color Index and a sample of paint left to dry or harden on this self-adhesive label that is later glued around the tube.

4 We roll the log on the acetate sheet filled with the paint paste to introduce it into the tube


316

RECIPES & PAINTING TECHNIQUES ATELIER ©2016 DAVID DAMOUR

It is possible to make an infinite number of recipes from all the materials and substances of the painter's trade. I will give you here all those that I formulated or developed and tested during my research. I had to make a choice among the most stable, because I make recipes almost every month, I love to experiment, but stability is above all, you have to be sure that the mixture delivers on its promises. This represents more than 200 recipes and skill sets, all techniques combined, that you can adapt to your work. Some of them require a lot of rigor in the formulation, that is to say that the dosages and volumes are very large, others on the contrary, allow interpretation, while keeping in mind that the purpose of all these recipes must serve the work only. Knowing these recipes will allow you freedom of execution in your art. Take notes of all your testing, because getting a finished product is one thing, but knowing how to redo it is another. Materials give us the power to do everything, we are no longer limited by not knowing them. In fact, the only limitation is that of our imagination. A very important point, it is ideal to use distilled water for recipes, bought in pharmacies or tap water that is boiled and stirred with a wooden spatula to remove its chlorine. . Avoid using bottled water which can be too mineral, you need pure water otherwise it can cause the mixtures to change (whiten) or even blue the mixtures because of the lime or other minerals sometimes contained in the water. depends on the region where you live: it is especially the rate of iron and minerals which must be the lowest.

Glassworks with decantation and filtration, i.e. 2 desiccators and 1 Imhoff cone on the right. on the left, a linseed oil put to purify and clarify in a salt water solution and on its right 2 flasks to sediment the water which can remain like this for years without evaporating thanks to the funnel placed above.

Pigments ©David Damour 2018


THE MATERIALS AND PAINT MATERIALS

Materials and binders for paints.

ATELIER ©2018 DAVID DAMOUR

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THE PROPERTIES OF PAINTS BENEFITS OF PAINTINGS

DISADVANTAGES OF PAINTS

Enluminure = Very luminous paint with very bright and powerful colors, you can paint everything using this aqueous technique as with all other polar techniques with natural gums; indelible after drying. Preciousness. Beauty. Colorant Juices = very bright and powerful colors. Tüchlein = glue painting imitating tapestry. Casein paint = very resistant paint physically and chemically, indelible, resistant to humidity once dry.

addition of plasticizer and anti-foaming agent required. Fears the light unless you protect the works with a glass or an anti UV varnish. Has a certain rigidity, possibility of cracks if it is not plasticized. Models difficult to achieve. Fragile to abrasion. Do not support the light Do not support humidity and iconoclastic insects Matt, brittle, very rigid paint = addition of plasticizer and antifoaming agent required. Very short opening time. Paint that can damage papers, check the pH of binders and final paints. Realization of models impossible. Relative physical and chemical resistance depending on the binder. Making the binder is difficult, rapid sedimentation, we cannot do any modeling or elaborate work. Relative stiffness.

The Inks = particular graphics, allows both to make very washed out paints which dry quickly and to achieve wet-on-wet effects with very interesting hazardous and variable results; indelible. Aqueous saponified shellac paint = Vivid paint, allowing to achieve solids and lines before painting in oil. Indelible, increased resistance to the light that it communicates to the pigments. Skin Glue Painting = Allows you to quickly paint like Tüchlein. Bright and fresh colors if made with pure pigments. Cera Colla = very flexible and very durable paint, which does not turn yellow even in complete darkness. Put in a tube, it can be kept indefinitely. Materia very interesting. Gouache = opaque and paste-like paint which makes it possible to make all kinds of highlights on aqueous, porous techniques. The Klache® = Gouache that I developed with modern components. Indelible. Bright and frank flat areas. Resists humidity. Fast drying. Plasticity. Watercolor = speed of execution, wet on wet, allows you to play with the shade of the support to bring it luminosity and liveliness. Transparency. Dry Pastel = dry technique allowing to represent everything with great realism, no drying, no waiting, spontaneity and precision. Acrylic = resistant to aggressive agents, UV, no yellowing, good resistance to light. possibilities of giving it all kinds of physical forms through mediums. Short opening time, dries quickly. Oil Painting = allows to create a pictorial space by playing with shine / mattness; possibilities of giving all physical forms to the paint thanks to a whole range of mediums and additives; moisture resistance. It should be exposed to indirect light. Alkyd Paint = same advantage as oil, but with a crosslinking time divided by 3.

Keep dry. Perishable, risk of pulverulent over time. Special tools and materials, constant heat. Redissolution after drying. Realization of gradients and velvety very complex if not impossible. Grinding of particular paints. Lack of liveliness, matt, dull paint, delicate after drying ; the paint gets thicker quickly, few layers possible. Decrease in tone when drying. Velvety and subtle melts difficult to achieve. painting techniques which take some time to learn to master. Short working time, delicate after drying, do not support humidity, the delicacy of the watercolor makes this painting a very fragile material Fragile, fears humidity and shocks, iconoclastic insects if the pastel sticks have not been protected with a preservative. Style softness. Risk of whitening or grayness over time, we are not sure, because we do not have 500 years of hindsight. Result a little cold compared to oil, unless you use hot varnishes (ketone) to enhance the paint. Slow hardening and crosslinking, waiting time, yellowing of paints. Do not expose to direct sunlight once the crosslinking is advanced and do not leave in total darkness. Do not use pure oil. The oil destroys the supports in the long run. Yellowing of paints. We do not have enough perspective on the stability of this chemical binder.

Ethylcellulose paints have good resistance to water and Matt paint with little character used without addialkalis. Good longevity. For making silhouetted inks and tives. insulating paints.


THE PROPERTIES OF PAINTS BENEFITS OF PAINTINGS

DISADVANTAGES OF PAINTINGS

Silicate binder = paint or sticks indoors on coated wood or outdoors on concrete, etc. Encaustic = Very durable paint that can be touched up at any stage and at any time during its development. Same advantages as the cera colla. Infinite overlays. Lightfastness, does not fear exposure in total darkness. Egg Temperas : The flesh of the painting is interesting and the smoothness of the material. Vivacity. As a dedicated technique, simple cracks to be achieved by superimposing a faster drying binder on the layer of egg paint. Emulsion = advantage of oil paints and allows depending on the volume of oleaginous material to give the material all kinds of physical properties such as the appearance of butter until the fine glaze. Microemulsions = High resistance to abrasion, better color intensity and greater resistance to coloring. stubborn paint. Polyurethanes = They allow painting of very thin layers which have great physical qualities; hangs on many supports, whatever their condition. increased shine (personal opinion) Synthetic paints in solvent phase = rapidity of drying, allows the encrustation of pigment in order to maintain their appearance of pulverulence. Pure resin painting = rapid drying, it allows retouching on oil and making quick, very nervous sketches. Glaze by dilution with a little black or clear oil. Rigidity, plasticity. Oleo casein paints = resistant to humidity, not afraid of water after crosslinking. Plasticity. Fat emulsions = like oil from which it borrows the benefits. Cellulose paints in solvent phase = indelible, rapid drying, allows painting on supports which fear water and humidity like all paints in solvent phase.

requires a protective varnish which must be requested from suppliers. Rigidity of pure films. Quick drying : Heat must be present throughout the process. Material cannot be borrowed from other painting techniques. It fears alkaline materials and substances and saline humidity. Rigidity. Fragility of the pictorial layer. Possible cracks, moldings impossible to achieve, because the binder hardens very quickly. work by hatching and separate areas required for modeling.

The oily Varnish = It is the queen of solvent-based paints, it allows you to paint like the great painters like Van Eyck; velvety and sfumato very numerous possible. Rendering of perspective and pictorial space. Strong shine. Very beautiful painting, drawing, agatized, exceptional rendering. Greasy tempera = it has the advantages of its constituents. Long opening time. The Fresco = Very luminous painting, it is perhaps the most luminous of all the techniques with the the Enluminure. It is also a very durable technique if the substrate and the coating are of good quality.

Difficult to do at first, requires a bit of learning and testing. Has the disadvantages of its constituents. Difficult to achieve, it is necessary to implement the components in a very precise manner. Increased shine for those who prefer mattness that can be tempered either by adding mattifying agents or by dry sanding with pumice stone. Speed of hardening; heavy material under the brush. Harmfulness of the solvents required for painting. Grinding of paints with special pigments. Painting difficult to use at first, requires a little practice. Yellowing; destruction of cellulosic supports in the long run. as for the oil of which it has the disadvantages. relative yellowing. fragility of the pictorial layer. Harmfulness of the solvents required for painting. Painting difficult to implement, requires great knowledge of the craft and painting technique. Waiting time between each layer. Destruction of cellulosic supports in the long run as for oil and all oleaginous binders, but less than oil. It has the disadvantages of its constituents. Yellowing. Waiting time. Working time allocated to a specific time "one giornata", one day; it is necessary to wait until the plaster is smoothed. Rise in tones (brighter) when drying to be taken into account.

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THE ENLUMINURE EGG WHITE PAINT The word the Enluminure comes from the Latin “illuminare” which means to illuminate, to make luminous. ”It is certainly the oldest painting technique with encaustic and fresco; it is the ancestor of all the techniques made with erasers. natural like gouache and watercolor. the Egyptians used eggs from ducks and geese because they did not raise chickens. In Europe it was not until the Middle Ages that the egg was used Illuminating is normally a technique using only the white of the egg, which is 68% albumin, from Latin "albus", white. Chemical Formula: C720H1134N218S50241 Minimum molecular weight: 18,400 g / mol Albumin contains the elements carbon, hydrogen, nitrogen, sulfur and oxygen, however their composition varies within certain limits. COMPOSITION OF PURE AND WET ALBUMIN

carbon C hydrogen H nitrogen N sulfur S oxygen O

50 at 55% 6,9-7,3%, 15 at 19%, 7%, 1,4%

ALBUMIN CRYSTALLIZES AFTER DRYING, IT CONSISTS OF THE FOLLOWING COMPONENTS

carbon C hydrogen H nitrogen N sulfur S oxygen O

51,48% 6,76% 18,14% 0,96% 22,66%

The word '"the Enluminure" belongs to the French heritage since the origin, it is a word of the French vocabulary, in Italy one uses the word of "miniatura". The Parisian illuminators of the Middle Ages were very famous for the beauty and the quality of their works. The nature of the Enluminure since the Middle Ages is twofold. 1. it is illustrative and 2. ornamental. it is only late in its history that the ornate letters appear around the 6th century, which had an enormous impact on the layout and later towards the 13th which gave birth to the borders and frames of characteristic flowers and plants. French manuscripts from the late Middle Ages. To be suitable for use in painting, the egg white must be beaten with a whisk or squeezed out with a sponge, until it foams strongly, forming a lot of foam. Leave to stand for a few hours or overnight, then collect the liquid at the bottom of the container, this is the basic binder to which various adjuvants are added, such as glycerin, honey, cerumen or an antifoaming agent. The clumping action of egg white is due to its composition, it is a colloidal solution of nitrogenous substances of 15 to 19% for the white, which coagulates by the evaporation of water. The modest amount of fat contained in the white,

around 0.26%, acts as a convenient plasticizer in the coagulated mass, which certainly explains the enthusiasm it aroused in the Enluminure and gilding. Egg white also contains 1.5% soda.

We thus count The painting

The binder is made from powdered egg white or albumin, a plasticizer such as skin or parchment glue and tree gum, plus a preservative such as camphor or sodium benzoate , and an anti-foaming agent if necessary such as cerumen (ear wax, a yellowish, waxy substance) [59] + pure plant and animal pigments or dyes which are carefully ground on the marble, first to distilled water then amalgamated with liquid egg white. The person applying the paint is called an "illuminator".

The Gilding

It comes in the form of impalpable sheets, with which we embellish the work. See gilding

The supports

You can use parchment, vellum, paper, ivory, cotton canvas, coated wood, etc. ...

The calligrapher or the chrysograph

This is the person who writes in letters of gold. If she wishes, she annotates her works with gilded and painted belles-lettres, but this is not required. Admire the magnificent illuminations at the National Library of Paris and you will see, the beauty of such works, it is as if they had just been painted. A few years ago I was able to see an the Enluminure exhibition from the Middle Ages at the Louvre Museum in Paris, no work containing highlighted texts. Enluminure is and remains a technique of painting with egg white. Some recipes can be formulated with solutions of cherry gum or gum arabic and sometimes tragacanth or xanthan gum, in order to give volume, plasticity and to give mordant to the paint. Personally, I use pure powdered albumin more often, because it is ready in 2 minutes by simply adding water and a little plasticizer such as glycerin, but be careful not to add too much, because it makes binders hygroscopic. As a starting point, plan to add a maximum of 4% plasticizer, the modern silicone antifoamer PDMS does this perfectly.


THE ENLUMINURE OF THE XXI CENTURY e

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Preparation of egg white to be used as a binder for the Enluminure.

1.Put an egg white in a bottle

2.Shake to produce foam, leave to act overnight.

1.

Glass wheel - agate mortar and pestle - albumin

1. The liquid of the enluminure, with white egg , settles on standing after a certain time

2.Let the white stand overnight

3.The next day we filter and recover the decanted and liquid part, it is the binder to which a preservative is added.

Grinding Pigments for the Enluminure

We grind the pigments in a mortar or on the marble, with distilled water, we add the binder to them then we continue to grind in order to amalgamate everything well and we put it in flasks. Adding camphor (or sodium benzoate) to the water or the binder, in addition to pleasantly scenting them, helps keep these liquid illuminators indefinitely. Organic lacquer pigments are excellent in illuminating because they are very fine (dissociated) in the range of 2 to 10 micrometers (µm). The paint is bottled, you will notice how the pigments inexorably end up at the bottom of the container, they are said to sediment. It suffices to shake the bottles to recreate the suspension of the binder with the pigment. A stabilizer could be added to prevent this from happening, but it's best to keep the uniqueness of liquid illuminators.

2. it is necessary to shake the bottles to restore its cohesion to the paint or to add a stabilizer. I do not add adjuvants I prefer to keep the uniqueness of the liquid enluminure

Black enluminure and various mixtures in liquid form


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THE ENLUMINURE OF THE TWENTY-FIRST CENTURY AND THE TÜCHLEIN TYPICAL RECIPE FOR AN ENLUMINURE BINDER

Materials

Quantities

Pure egg white

20 ml.

Skin glue Ox gall or silicone anti-foaming Camphor Water if needed

14% 2 drops for rebellious pigments. a point or 1 gram. up to 5 ml

Almost any pigment can be used in Enluminure, provided they are properly ground in a mortar or on a marble and if necessary purified by levigation with water. Synthetic pigments are easier to grind, because they are more dissociated, they are very fine. BINDER RECIPE WITH TREE GUM Materials Quantities Prepared Egg White Solution 20 ml Cherry Gum Solution 5 ml or Arabic Gum Ox gall or silicone anti-foa2 drops ming for the rebels pigments PDMS Camphor

3 drops a point or 1 gram

The pigments likely to change color to a certain extent are those - (containing copper like azurite, zinc like zinc white and mercury like vermilion, natural cinnabar being more stable) not supporting soda ( sodium hydroxide NaOH), contained in the egg white, however partly so weak, that the changes are not systematic, it is necessary to make preliminary tests, because each sample of pigments depending on its origin may react differently. When the pigments are ground in a mortar, we can put them in flasks, knowing that they will sediment over time; to avoid this you can add 1% xanthan gum or Laponite to your paints. With regard to the light stability of the pigments in the Enluminure, as a rule, since the works are in books, protected from the ravages of time, the problem does not arise; for unprotected illuminations, it suffices to varnish them with a 2% solution of Tinuvin 292, 3% of Tinuvin 900 [62] and 24% of dammar resin in 10% of xylene and 60% of shellsol D40, it is a perfect anti-UV varnish, where to use an anti-UV glass. I made Illuminations-Tüchlein-tempera (parts with egg white, others with casein and others with skin glue in very large formats on virgin cotton canvas, glued or not with casein) in the manner of the Tuschlein, a tüchlein, is a painting executed in tempera on fine linen or cotton canvas.

The pigments are applied pure with water or with a little natural gum or glue. You will notice the use of. 1. The cochineal for red. 2. Molybdenum orange (replaces the orange lead). 3. The gutta for the yolk. 4. The gall nut for the flesh 5. Limonite for land. 6. Indigo from Morocco for the sky. 7. Smoke black around the edges and mixed. In all and for all 7 pigments for a colorful palette. This is what one could call a modern Illuminated Tüchlein, because the means evolve, the materials too. Artists have always adapted. If, for example, a pigment such as Indian yellow no longer exists, what to do? Just use its modern substitute Pigment Yellow PY 150 12764 ; I also replaced the orange lead with molybdenum orange, which has a lower density and therefore easier to use for painting.

The Tüchlein

Tüchlein is a word of German origin, "Tüch" means "fabrics" and "Lein" means "linen" and in its modern sense "Canvas". In specialized literature, the technique evokes a painting made with a water-based binder and animal glue on a linen canvas glued and sometimes printed with a colored wash. The tüchlein technique is specific to the 14th and 15th centuries in Flanders and Germany. It is found in Italy, but the word changes to "a guazzo" which means in French "gouache". Eminent specialists claim that this technique of painting on canvas made it possible to produce works at a lower cost, because one can very quickly achieve accomplished works at low cost, the basic material, the glue, not being very expensive. The technique disappeared in the 16th century. Pieter Bruegel the Elder was one of the last great masters to use this very practical technique in lively and fresh colors. Using skin glue, albumin, casein, gum arabic or fruit tree, it is possible to create on canvas, works of spontaneity and nervous graphics. Didn't know I was doing Tüchlein until I read this article: https://ceroart.revues.org/1737 This technique is in a way the ancestor of gouache and Flashe®. Very good article on the tüchlein technique (English) https://www.nationalgallery.org.uk/upload/pdf/ roy1988.pdf


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EXAMPLE OF MODERN MIXED MEDIA ENLUMINURE AND CASEIN ON CANVAS Gamboge with casein

Gall nut + arabic gum

Indigo from Morocco with skin glue

Smoke black + Indigo with white egg + tylose

Indigo + Smoked black with white egg

Limonite with white egg

Cochineal + Limonite with white egg

Gamboge + Cochineal + limonite with casein

Cochineal with casein Cambogia with Casein

Indigo from Morocco with skin glue

Gall nut + arabic gum

Juice of molybdenum Orange with skin glue Indigo + Smoked black with white egg

molybdenum orange with casein

Cambogia in lavis with casein

Smoke black with casein

"The Beast of the Apocalypse" Enluminure - Tüchlein - Tempera. White Egg , casein, gum arabic and skin glue on cotton canvas prepared with casein. 3 meters x 2 meters. © 1999 David Damour Private collection


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GRINDING WHITE EGG PAINTS

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Place the pigment in a mortar.

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Once the finely ground pigment is added the binder, here 1 g of powdered albumin which is faster to prepare or from a liquid egg white expressed the day before using a sponge or made by decanting egg white, stiffened as if to make a meringue.

5

Add distilled water to grind the pigment

Thoroughly mix the albumin with 10 ml of water and the pigment, which constitutes a "liquid Enluminure", leave to stand for one hour, then grind again. If this makes too much foam, add 2 drops of silicone anti-foaming agent or earwax.

6 Realization of a round color chart of Victoria green on paper with the liquid Enluminure just prepared.

Victoria green final color chart with Liquid Enluminure, no plasticizer has been added, note the creamy nature of the paint, but in order to prevent this from foaming, you can add 2 drops of anti-foaming or cerumen to the mixture and a drop of plasticizer such as silicone PDMS.


THE TECHNIQUE OF GRASS JUICE OR JUICE FROM DYES antifoaming

+

Color chart of Victoria green to egg white, without plasticizers or defoamers.

The paint is applied on canvas not glued or primed, historically the canvas was made of linen or silk, but in modern technology one can use cotton and paper. It was a very common way of painting from the 15th century to the beginning of the 18th century, particularly in Italy where it was first used to imitate the technique of tapestry. In the Middle Ages, the "succhi" technique was used above all as a canvas or studies for the subsequent production of carpets and ornate fabrics in order to replace the traditional cardboard boxes. Victoria green color chart, the From the 16th century, dye juices were mainly used binder has been plasticized with as a decorative paint for the theater and gradually be1 drop of silicone antifoam. came a medium for embellishment and fixed interior decorations, as it imitated the appearance of tapestry. From the 17th century, artists' enthusiasm for this technique grew, because it allowed the rapid creation of works with a watercolor effect. The technique of coloring juices on canvas is very interesting, because there is no binder only a mordant, alum and as a diluent for water, which constitutes very high-color paintings like casein and Enluminure. This technique makes it possible to paint very quickly on canvas or paper with all vegetable dyes, animal lacquer pigments and synthetic dyes.

Fresh egg white paint color chart.

The excess of albumin makes it possible to make crackled paints on paper, but resistant and plastic.

The addition of plasticizer and antifoam can reproduce a paint film smooth and of good qualities.

The Succhi d'erba or Grass juice also says juice from dyes

"Succhi d´erba" is a compound word that has its origins in Italy. Succhi which is the plural of succo means "juice" in French and Erba translates to grass. Which corresponds to "grass juice" or "colorant juice". Erba succchi can be defined as a painting made with vegetable dyes or lacquer pigments, with alum as the main mordant, but other mordants can be used such as alumina.

Symbolic Circus. Coloring juice and Enluminure on paper - 40 X 31 cm © David damour 2001. Private collection

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ENLUMINURE SWATCHES WITH PIGMENTS AND WHITE EGG 5 drops of Bistre + 2 drops of Cochineal

1 vol. cochineal + 2/5 of Indigo = A Blend

Indigo + Bistre on an indigo underlay very diluted 1/2 vol. of A Blend + 1 vol. Gum cambogia + 1 vol. indigo 15 drops of Brazil wood + 5 drops of gall nuts

pure Indigo from Morocco

Gamboge + B Blend

Cochineal + Indigo = B blend 1 vol. Cochineal + 1 vol. Indigo on a layer of gall nut 3 drops of Bistre + 6 drops of Gamboge

Brazil wood 8 drops + Cochineal 2 drops

1 vol. of Cambodge + 1 vol. Indigo

Bistre 10 gouttes + Cochineal 8 gouttes

Cochineal mixed with lead white

White lead with egg white

Carbon black + indigo on the left, carbon black on the right

Cochineal + Indigo


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PALETTE PIGMENTS & DYES CHOSEN FOR ENLUMINURE DYES JUICES AND TÜSCHLEIN

White Gofun Shirayuki

Titanium white XSL

Isoindoline yellow

Gamboge

Lapis lazuli

Blue Maya

Victoria Green

Beaune Gray

Indian yellow imitation

Paliotol orange PO59

Orange irgazine PY 110

Indigo of Marocco

Chrysocolle

Nettle

Lamp black

Grain Stil NY 14

Beech charcoal bistre

Limonite N°2

Gray spinel PBK26

Van Dyck Brown NBr 8

Gall nuts

Sepia

Perinone orange

Brazil wood

Orange of Molybdenum

Hostaperm Pink

Light ultramarine blue

Cobalt blue turquoise

Mexican cochineal

Lacque of madder

Azurite

Ploss

Heliogen Blue

Red cabbage

Egyptian green

Green-grey

Malachite

Heliogen Green

Synthetic indigo

Alizarin violet

Cobalt violet

Epidote


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ANIMAL HIDE GLUE - CASEIN PAINT

Animal Hide glue is an aqueous painting technique performed cold or hot with the whole range of glues such as skin, nerves and bone glues, but also with fish glues such as isinglass and glue Saliansky, there are also glues from milk protein such as casein. Casein is precipitated from skimmed milk which is produced after centrifugal separation of whole milk. 1 Skim milk can be acidified to produce casein acid or treated with an enzyme, resulting in what is known as rennet casein. The precipitated casein curd is separated from the whey, washed and dried. Water-soluble derivatives of acidic caseins, produced 2 by reaction with alkalis, are called caseinates. The amount of casein in whole cow's milk varies depending on the breed of cow and the stage of lactation, it is generally between 24 and 29 g / L. Caseins contain between 0.7 and 0.9% phosphorus, covalently linked to the protein through a phospho- 3 ric ester bond of serine, isolated from casein hydrolysates. Its presence alongside phosphothreonine is constant in all phosphoproteins, to which it confers sensitivity to alkaline agents. It can constitute bridges by joining the peptide chains of proteins by phosphoric or pyrophosphoric diester bonds. Casein is therefore known as a phosphoprotein. Casein painting on decayed cotton or linen canvas, glued or not and not primed is very easy to achieve; it suffices to make a basic binder which will be diluted with cold water as and when depending on the final destination of the paint. For the basic casein binder recipe, plan a larger container, because it foams strongly : Casein binder recipe • 50 grams of insoluble commercial casein. • 300 ml of hot water. • 15 grams of alkali such as ammonia. • 20 drops of sodium benzoate as a preservative. • 5 to 10ml of glycerin or <5% • 1 to 3% of Tylose as an anti-flocculant agent

4

5

Casein glue ready to use. It can be diluted with 20cl of water and give it body by adding <10% "Laponite©" or any other gelling adjuvant such as xanthan gum

Dry film of fresh cheese casein. By adding less lime (alkali), the binder will be whiter.

Binder of casein with cream cheese and slaked lime + glycerin + antifoaming agent + sodium benzoate. The binder has a pinkish tint, but this does not affect the final paint film.

Leave on for 12 hours then dilute by adding another 15 to 20 cl of cold water then the glycerin. This constitutes our paint binder. Personally, I make the final binder in a blender and I add 10 to 20 drops of antifoam (to avoid bubbles) which gives the binder a plastic character and gives it a translucent shade as in the photo opposite. The binder will be indelible and insoluble once dry, whether made with borax or ammonia. The binder is tough and brittle if not plasticized with glycerin and antifoam. You have to plan for a drop in tone when drying, which is why I most often use pure dyes to achieve such works. Casein gives dull films. Binder made with insoluble commercial casein dissolved in ammonia + glycerin + antifoaming agent PDMS + sodium benzoate


CASEIN PAINT

Pure casein base binder without adjuvant

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Fresh casein binder base after adding glycerin and antifoaming agent

+ drying

Film of pure casein base binder without any adjuvant after complete drying. Note how brittle it is, which is why it is necessary to add a plasticizer to it. I add 20 drops of silicone defoamer as a plasticizer, you can also add <3% laponite. the binder has a caramel tint which is translucent.

Final binder of casein paint after addition of glycerin and anti-foaming agent, note how shiny the binder is. He's so tough that it is very difficult to remove it from the porcelain support.

Casein paint for painting large formats: from left to right, gum-gutte, limonite, brown, naccarat red, dark greenish verdaccio and cochineal were used to paint the work on the next page (plus indigo from the Morocco). You can add Laponite® or any other gelling filler to give body to the casein paint.


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CASEIN PAINT

Preparation of casein paints

To grind casein paints, you must first grind the pigments in pure water on marble or in a mortar with a pestle and mix them with the base binder. There are pure water pigment master paste mixes available for sale : http://bit.ly/Pâte-de-pigment-a-l-water. These aqueous pigment pastes are very practical. Thus we can very quickly produce casein paints by simply mixing with the binder, then works with bright colors and which dry very quickly. However, the casein technique is not without limitation, it does not allow for subtle gradations as with oil paint; this requires the use of the hatching system well known to tempera painters (egg yolk). It is the technique of solids and large masses of colors; I sprinkle glass glitter on the bright parts in order to catch the light to bring out certain light parts compared to the shadows, because casein on canvas is matte. Casein has a typical odor which disappears after complete drying. Too many successive coats of casein paint increase the porosity of the film. Apply the paint in two thin and regular coats at a minimum interval of 8 hours in summer, wait 2 days in winter.

Palette for casein paints

Choose pigments that support the alkalinity of the binder which is around pH 10-12 and which can be lowered by adding a few drops of Ethomeen C25 diluted beforehand with a little of the base binder.

White Gofun Shirayuki

Spinel black

Gall nut

Bismuth yellow

Gamboge

Indian yellow PY150

Limonite

Hostaperm Pink PR122

Cochineal

Paliotol orange

Molybdenum orange

Cobalt Blue

Indigo from Morocco

Cobalt Blue Turquoise

Titanium white XSL

Cobalt green spinel PG50

Casein painting on cotton canvas 110 cm X 150 cm Personal collection © 2016 David-Damour Alizarin violet

Heliogen Green PG36

Synthetic indigo

Victoria Green

Ultramarine red


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ANIMAL HIDE GLUE - SKIN GLUE PAINT Animal glues are adhesives, high molecular weight polymers in the form of organic colloid from hydrolyzed collagen extracted from animal skins, connective tissues (nerve glue) and bones. Glue contains two groups of proteins: "Chondroitin", which represents its strength of adhesion and gluten, which contributes to its gelling strength. Animal glue comes from the simple hydrolysis (chemical decomposition of a substance by the direct or indirect action of water) of collagen which is the main protein constituent of animal skin, connective tissues and bones. The best skin glues are those in plates, they are made all over the world from rabbit collagen. The glue is also available in powder or in small blocks, which are easily dissolved in water. The higher qualities give clear and translucent solutions, which makes it possible to recognize its value and destines it to be used for sizing, for making thin plasters and as a binder for distemper painting. Animal glues have been used since time immemorial, they made it possible to replace bitumen glues and birch pitch glues, obtained by smothering the bark of the tree. Murals dating from 1500 to 1000 BC. AD show its use for bonding wood. Many art objects and furnishings from the tombs of Egyptian pharaohs are bonded or laminated with some type of animal glue. The first references in the glue literature providing simple procedures for making and using animal glue are described since 200 BC. J.-C. Much of the initial development of adhesives based on natural products came from the wood and paper industry. The 5 classes of adhesives used most of the time were animal glues, casein, vegetable proteins, starch glues and blood albumin glues. One can count as adhesive formulations sodium silicate, mucilages of natural gums, asphalts and bitumens, shellacs, and to a certain extent natural rubber (cis polyisoprene) derived from latex. See this very complete article on glues.http://www.lekit.design/ img/C4.pdf Rabbit skin glue is used in traditional techniques for Grounding wood (although casein is stronger in terms of adhesion), foil gilding and as a paint binder. First put to swell in water, then heated in a water bath, it is applied hot, once it has cooled it becomes gel. Its advantages are the solution in water, its reversibility and its opening time which allows repentance during marouflages. In painting and gilding techniques, it is used both as a glue for canvas and panels, and as constituents of traditional plasters, as well as as a binder for tempera paints. Initially to make the glue, the skins are kept in a lime suspension for 1 to 3 months until the lime hardens. This process allows for the loosening of collagen

bonds in the skin so that it can be extracted easily. After the lime treatment, the skins are washed several times to remove excess carbonate and then the glue is extracted by cooking in boiling water; the glue which is extracted therefrom is then concentrated using an evaporator. The concentrated glue is either molded or dried in tumble dryers and sprayed for final packaging. The two main types of animal glue are skins and bone glues. Animal glues vary in strength, but rabbit skin glue usually has high strength, good viscosity, and excellent elasticity. Real rabbit skin glue tends to gel at lower temperatures, making it easier to use for sealants. Skin glue is by far the better of the two, giving a fairly neutral pH in solution, usually in the 6.3-7.5 range, although wider variations are possible. Bone glue is generally acidic, having pH values ​​of 5.6 to 6.4. A glue with a high acidity absorbs less water and tends to stabilize more slowly than a glue with a low acidity level. Animal glue is soluble only in water, it is insoluble in fats, alcohols, oils and organic solvents. When placed in cold water, the glue absorbs water and swells. The glue dissolves by the action of heat to form a solution. When this solution cools, the glue forms an elastic gel. This property is thermally reversible and the application of heat liquefies the gel. The gel or melting point of an animal glue solution can vary below room temperature up to more than 42°C depending on the quality of the glue, its concentration and the presence of adjuvants such as as preservatives, plasticizers or anti-foaming agents. TECHNICAL DATA TYPE OF SKIN GLUE

Principe actif Chemical Formula du collagène pH Water Lipides Cendres

Collagène hydrolysé C102H151O39N31 6,3 à 7,5 12,6% 5,6% 1,2%

Animal glues can have an undesirable tendency to foam, the development of small air bubbles in the glue matrix can disturb the uniformity of the cured glue film and can weaken the bonds and the final consistency of the film. Skin glues generally have greater cohesive strength than bone glues which have highly cleaved molecules and which have lower tensile strength and therefore are much more brittle. The tensile strength of skin glues is typically around 40 megapascals.


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SKIN GLUE PAINT Collagen-derived glues, unless they have been modified by the addition of tanning agents, are relatively water resistant, in general they swell easily when exposed to water and redissolve when exposed. again heated, even after a very long time. The lower the original concentration, the less redissolution of the adhesive film will occur. Bone glues redissolve more easily than skin glues, supposedly due to their more pronounced molecular cleavage from their protein matrix. The ability of animal glues to redissolve may be reduced if the protein comes into contact with metallic ions such as metallic foils, iron tools, pigments containing ferrous or ferric oxides or with certain organic pigments as well as with tannins.

Preparation method

Always make sure to set the glue to a minimum concentration, you can always add more if it is missing; for example and as a benchmark, the glue once cold must be between the gel and the liquid form. For tempera paints, 60 to 80 grams per liter is a good ratio, or a glue of strength between 6 and 8 grams.

Real rabbit skin glue in plates that I have put aside for 25 years, it is still as active as the first day. It must be broken into small pieces to make it swell in cool water.

As an adhesive, check the adhesion of the glue by dipping a piece of wood in the pot, if the glue does not impregnate the wooden stick it is because its concentration is good, add a little water if it is too much thick. I use porcelain cups in which I pour the binder to be tested, so I check the quality of the paint films by letting them dry completely, this allows to see the plasticity, roughness, shine and final mattness of the binder. The collagen in the glue can be modified with a wide variety of adjuvants to make it more water resistant by the addition of 1% by weight (to the dry glue) of alum (aluminum sulfate), this method is efficient; avoid formaldehyde. Silicone defoamers can prevent film brittleness and cracking. An addition of 5% glycerin increases the flexibility of the glue, but also increases its hygroscopic character. The addition of 5 to 10% by weight of urea prolongs the gelation time and also increases its flexibility, ultimately producing a glue that is liquid at room temperature.

Animal glue painting recipe

Rabbit skin glue, bone glue, parchment glue, nerve glue and technical gelatin make it possible to make paints known as tempera inexpensively, easily and quickly. Diluted with water, they are excellent binders for carrying out both studies and paintings on decaturated canvas and glued with an 8-10 g glue, so the paint instead of being caught in the absorbent support allows the touch of dragging and quickly creating large, colorful areas of paint. Swell 60 grams of dry skin glue for 24 hours or overnight in as much water as necessary to cover all the dry matter.


SKIN GLUE PAINT

1

2 60 g of skin glue put to swell in pure water

The next day, discard the water or not, there are two opinions on this subject, personally I throw the water, because if the plates contain impurities it allows them to be removed, to a certain extent it purifies the glue, however this only valid for plate adhesive. Replace the water with 60 cl of fresh water. Heat the glue in a water bath to 42 ° C to melt it and dissolve it completely in water. The collagen in the glue should never be heated above 55 ° C, as this weakens and destroys its protein.

1.hot glue Détrempe

Grind the pigments first in water with a pestle in a mortar or on a marble to form pigment pastes. so all that remains is to mix the pigment with the hot glue solution and place in small porcelain or aluminum containers kept on fire, on an iron plate, place on a hot plate as for the encaustic. It is necessary to maintain a certain heat so that the glue remains in solution which allows it to be used for painting. Use hot water to thin the tempera paints. However, you can paint flat with gel glue, it is very interesting and very pleasant; it is possible to add 2 to 4% of Laponite to it to use it cold.

60 grams of skin glue after swelling 24 hours

2. Distemper cold adhesive

The skin glue which remains liquid at room temperature is made possible by the addition of urea and a little table salt. An example of this type of liquid glue is "Old Brown Glue", created by W. Patrick Edwards, director of the American School of French Marquetry. Stress tests have been performed positively on this liquid skin glue and it can be compared to hot skin glue for its bonding strength, however, personally I only recommend it as a paint binder, not for wood Grounding. Initially, it is necessary to swell the skin glue for 24 hours, then heat the glue and when it is lukewarm add 5 to 10% by weight of urea dissolved in a little lukewarm water with 1% of table salt.

Use of paint

Use hog bristle or synthetic brushes that resist the relative heat of the paint. The application is done in thin layers on paper, cardboard, wood or decrepit canvas, glue or not as desired.

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SKIN GLUE PAINT

The disadvantage of the skin glue technique lies in its solubility, so that if more than one coat has to be added, there is a risk of fading the undersides, which is why this painting technique tempera is excellent for painting alla prima, for studies or rapid sketches for oil or any other technique. If you want to make the glue insoluble, it is possible to add either 10% egg white, the least harmful method for the glue, otherwise add up to 20% of a 10% alum solution in some water.

Alum in solution at 10% in water

Sodium Benzoate

Glycerol

Once the painting is finished, it is possible to fix it in order to make the paint film more resistant to ambient humidity as well as to direct water. To complete the work, it is advisable to spray the dry paint with a 10% solution of alum in water, which removes the skin glue from its ability to swell and redissolve on contact with it. water. Avoid using formaldehyde which makes paints unstable by imparting a friability to them, which makes them pulverulent over time; I personally noticed this state of affairs on 20 year old paints to which I had added formaldehyde as a preservative as was customary in 1990. As for the encaustic, it is possible to use aluminum containers with screw-thread lids to keep the gel glue cool, but also for hot glue to paint easily, however aluminum transmits more heat than the containers. porcelain. Avoid heating the glue for too long, as this causes it to lose its strength and adhesive qualities.

4 3

We heat water to 80-85 ° C for our water bath in order to dissolve the skin glue.

With a water bath at 85 ° C, the skin glue is completely dissolved in 10 minutes, the glue reaches ~ 42 ° C. The glue will keep for a very long time in the refrigerator if you add 20 drops of sodium benzoate.


SKIN GLUE PAINT

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5 Electric hotplate on which an iron pan is placed in which you have to pour the water from the bain-marie which was used to cook the glue since it is already hot, pour porcelain or glass containers up to the brim. to keep the skin glue warm while painting. The plate is set to medium to impart enough heat, it takes about 15 minutes for the porcelain and glass containers to be hot. The advantage of porcelain is that you can heat less and work longer without risking destroying the collagen in the glue. Use a syringe to fill the small containers. Add dyes or finely ground pigments in the hot glue, then mix with a brush, here a hostaperm pink, a titanium white XSL and a synthetic indigo which constitutes our base paint with the skin glue.

6 The advantage with dyes is that no prior grinding is necessary. Add beef gall for the rebellious pigments that have difficult to mix intimately with water, like hostaperm pink. The ideal would be to prepare water pigment pastes or buy them here

http://bit.ly/Pâte-de-pigment-a-l-water


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SKIN GLUE PAINT Palette for Skin glue Paint Pigments chosen to paint with skin glue. iron oxides, earths and dyes are compatible with skin glue tempera.

Gelled skin glue, synthetic indigo and Hostaperm pink paint with fresh skin glue on raw linen. I added 2 drops of defoamer in the paint and 1 gram of Laponite to plasticize it.

Titanium white XSL

White Gofun Shirayuki

Manganese Gray

Spinel black

Hostaperm Pink PR122

Cochineal

Nickel titanium yellow

Gamboge

Van Dyck Brown NBr 8

Indian yellow

Paliotol orange

Sepia

Skin glue paint made alla prima. You will notice the liveliness of the pure pigments used: cobalt blue, cochineal, limonite, gumgutte and smoke black. "Discord". Skin glue paint on uncoated cotton canvas. 100 cm X 150 cm. Private Collection France © 2016 David Damour.

Cobalt Blue

Light ultramarine blue

Cobalt Blue

Verona Green Earth

Victoria Green

Alizarin violet

Heliogen Green

synthetic indigo

Indigo froM Morocco


INKS : WATER-BASED PAINTS AND LAVIS Ink is a liquid, most often consisting of an intimate mixture of dyes, plant, animal or synthetic materials, with water, glue or with bleached and saponified shellac; Other inks are made by reacting iron or alum salts and plants, resulting in a variety of colors depending on the base or acid used, but they are corrosive. See list of pH Pigments are generally solids which are virtually insoluble in the medium in which they are dispersed. The pigments are therefore not in the form of a solution in the ink, but in the state of suspension and that is why if you choose inorganic pigments to make your inks, they will settle as in the photo below. I therefore advise you to choose dyes to make your liquid inks.

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Leather was soaked in tan pits for at least a year before being worked, but at the end of the 19th century industry replaced it with chrome. The tannin of the gallnut makes it possible to stiffen the linen and cotton fabrics [62]. Galle nut makes it possible to make black ink by mixing it with iron sulphate. Gallnut ink was used by the Egyptians 2500 BC as for the real Indian ink, it would have been invented by a philosopher named Tien-Lcheu, 2697 BC. stick ink dates from AD 300. AD approximately.

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HOURS

Gall Ink Recipe N°45 Liquid Ink Mine Orange after shaking the bottle

sediment ink Mine Orange

In liquid ink recipes, colorants can be up to 20% of the ink's weight, binder about 70% and additives about 10%.

The Gall nuts

The gall nut is an outgrowth, a bud of an eastern oak species, bitten by insects of the Oak Cynip family. [61] The walnut harbors a larva which develops an acid in the fruit to create tannins. Gall nuts appear as a cherry-sized ball containing up to 70% tannin. Tannin is a substance of organic origin that is found in almost all plants and in all their parts, bark, roots, leaves, etc.. They have been known since ancient times. In the Middle Ages, we used the tannins of the gallnut [47] for the preparation of leather.

Reduce to a very fine powder, • 30 g of Gall nuts that are boiled in: • + 50 cl of water for 5 minutes, let stand for 12 hours. Filter through cheesecloth then add cold to a glass container + 10 g of iron sulphate. Stir the ink with a wooden stick, then add to stabilize the solution + 5 g of arabic gum pre dissolved in + 10 cl of water. We check the final pH of the solution, if it is too alkaline, we add either a little vinegar or a little lemon, both light acids. You can thicken the ink by adding more gum arabic or xanthan gum. As a preservative, camphor is excellent for inks as well as for all natural aqueous binders, 1 to 2 grams of camphor are added per liter of ink. It does not matter if the camphor does not dissolve, it communicates its properties even in the form of crystals; it can be replaced by 20 drops per liter of sodium benzoate.


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INKS : WATER-BASED PAINTS AND LAVIS Gallnut Ink Recipe N°46

The secret to making ink is the tannin in the case of gallnut ink. Mix 20 parts of very finely ground walnuts 10 vol. gum arabic solution (see No. 45) 20 vol. iron sulphate 30 vol. of white wine. Cook the preparation for about 20 minutes. This is a very simple recipe and the gall ink is very pleasant due to its dark brownish tint.

Iron gall ink done in cold way without any heat

Chinese ink solid stick N°19

Gall nut from Alep

Very clear tree gum solution, to replace gum arabic which is incompatible with iron salts, otherwise cellulose such as klucel is used

White wine

Iron sulphate crystals

Liquid inks black on the left Graphite on the right

Mix and let swell overnight 20 g of skin glue or dry beef glue 5 g of sturgeon or dry fish glue 1 liter of distilled water Then the next day, add 50 g of carbon black 5 g of camphor 5 drops of ox gall We do, cook over low heat (do not boil) until reduced half mixture, then add: 2 ml of rapeseed or sesame oil, or any other nondrying vegetable oil, this oil is mainly used as a plasticizer. Let cool and make a ball of this preparation. Put this ball in a cotton cloth that is placed in a skimmer India ink stick mold by over a pot of boiling ©Chen Chia-te. Photos de ©Jimmy Lin [110] water, the steam will continue to cook this dough while softening it. After 15 minutes, the ink is ready to be mixed to expel the air it contains and give it cohesion. All that remains is to roll, amalgamate this dough for a few hours, using a hammer or any other utensils on a hard surface such as a marble or a stainless steel appliance to make homemade lasagna or in a iron mortar using an iron or wooden pestle. When the material becomes elastic, we make round shaped sticks, or we place it in a mold in order to give it a perfect shape. The solid ink removed from the mold is placed in a box in Ink stick which we have taken care to put wood chips or pieces of blotting paper in order to absorb the residual moisture. This solid ink is allowed to cure completely for a minimum of 3 weeks. The older it gets, the better it gets. The best stick inks are those that are decades old.

Gallnut ink


INKS : WATER-BASED PAINTS AND LAVIS 3 tips for making an ink stick:

To obtain a perfect solid ink, you need: 1. that the lamp black is very pure and of superior quality. 2. that the skin and fish glue be pure and of excellent quality. 3. that the ink paste is well rolled and pounded. If these three conditions are met, there is no need to use any other solutions.

Recipe based on ancient Chinese treatises

We take the purest smoke black that is, that of the reference "lamp black" is the best, it is the pigment Black PBk7 77266, we pour it into a fireproof container and then pour on the black , the hot glue melted in the solution, taking care to pass the latter through a sieve that is placed on the container. The dough thus formed is then stirred and the whole is amalgamated. We then form a ball with the powder which attaches to the sides of the vase, we wrap the latter in a piece of canvas and cook it in a bain-marie for 1 hour. After baking, the black mass is allowed to cool a little then we begin the lamination which will last a long time for a perfect amalgamation of the materials, this is the second secret of the success of this ink, the more the black will be intimately linked with the glue and the other ingredients, the more consistent the stick and therefore of good quality. After kneading, this bread-shaped ball is flattened and passed through the mold or else it is given the shape of a log 10 cm by 2 cm in diameter. [110]

For gilding solid ink sticks

Take very soft breads, knead them, shape them into sticks and sprinkle them with a strong glue solution, wrap them in gold leaf and let them dry for a while in a draft. As soon as they are dry, we put them in hot ash after wrapping them in aluminum foil. When we remove the sticks from the ash, instead of brushing them we polish them with a piece of jade or agate. After this browning, the ink bar is wiped with a piece of lint-free cloth, polished again with an agate, and dried in a dry place. As soon as the ink is completely dry, we wrap it in paper, then whenever the weather is nice, we open the package, we wipe it off, we leave the stick for a while in a draft and we wrap it up again. If the weather remained humid, then the package could be opened in a room kept at a temperature of at least 20-22 ° C, without ever exposing them to a higher temperature. By this process, the glue can easily be dried in less than a month. All the steps I have just described must be done in a place well sheltered from humidity, as it breaks down newly made inks, in France the best months are the summer days to make the ink.

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Recipe N ° 20 of indelible ink 50 cl of water 20 g of arabic gum 10 g of oxalic acid a hint of camphor 10 to 40 g of plant or animal pigments Put all the ingredients in a glass jar, stir until the materials are completely dissolved, then put in a stoppered bottle. Wear a mask Dilute with water if necessary. The acidity is neutralized by the addition of a base, such as borax, soda or ammonia. Check with a pH meter if necessary. Be careful, Oxalic Acid is harmful in its pure state

Recipe No. 21 liquid India ink 6 g of dry skin glue put to cook in 50 cl of water then add 20 g of carbon or lamp black 10 drops of glycerin stir and add 3 drops of beef gall or defoamer a hint of camphor Continue to stir, off the heat, until the materials have completely amalgamated, then put in a stoppered and airtight bottle. You can add water to dilute this ink.

Recipe N ° 30 bis of Printing Ink 5 ml of polymerized linseed oil (stand-oil) 15 ml of drying oil / black oil 8 ml of liquid varnish 10 g of Magnesia 10 ml of turpentine 20 g of pigment Adjust the dose of pigment according to the applications. Grind the pigment and the magnesia with drying oil on the marble, put in a pot then add the polymerized oil and the liquid varnish, mix well then dilute with turpentine and as needed with thinners evaporating rapidly such as essences or shellsol T.


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INKS : WATER-BASED PAINTS AND LAVIS Recipe N°36 bis Egyptian ink we make this ink by boiling 20 cl of distilled water to which we add 80 g of blanched shellac to which we add off the heat

Palette of very fine pigments and dyes chosen for the ink

10 g of ammonia or borax pre-dissolved in 10 cl of water, put back on the heat when the effervescence stops and then incorporate the desired pigment 25 g to 40 g of carbon black (but we can make this ink, with gum-gut, cochineal, etc. ...). This ink is resistant to time and chemical agents. It is diluted with distilled water

Titanium white XSL

White Gofun Shirayuki

Atramentum

It has a beautiful brilliant shine. If it foams too much, add 2 drops of anti-foaming agent

Candle Black

Isoindoline yellow

Genuine Sepia

Gall nut

Brazil wood

Beech bistre

Cochineal

Gamboge

Irgazin Red

Egyptian Ink with Gambodge. 1997

Ink recipe N°103

Indian yellow

Van Dyck Brown NBr 8

Paliotol orange

Green-grey

Hostaperm Pink

Synthetic indigo

Heliogen Green

Indigo from Morocco

Nettle

Red cabbage

Blue Heliogen

we make this ink by mixing 13 g of dissolved solid PVA + 80 g of hot water = 60% 10-40% ethyl alcohol depending on how fast you want the ink to dry PEG 1000: 50 g for 50 g of water = 10%

Victoria Green

10g of Albumin for 73g of water = 20% Ecosurf EH6 = 1% to wet stubborn dyes that do not like water and polar materials This ink is 90% indelible without albumin, otherwise add 10% PEG to make it indelible Add 0.5 to 1% sepiolite to stabilize the ink

For information, the body tattoo ink is a mixture of: water, Propylene Glycol, Isopropanol, Glycerin, Polyethylene glycol (PEG), PVA + a non-toxic Pigment.


THE CERA COLLA OR WAX IN WATER Cera colla is a wax milk that comes in the form of a milky white liquid, crumbly and soft to the touch, but that can also be kept in a solid form with the appearance of small blocks that will be rehydrated. at the time of use to prepare paints. Beeswax and carnauba wax are saponified and then emulsified with a resin, a glue or a gum, with a secondary binder in fact, the wax being the primary wool. Cera colla is a mixture of bleached beeswax and carnauba wax in distilled water, to which is added mastic resin dissolved in turpentine (1) or skin glue (2 ) as in the original technique. It can also be made as modern recipes with a solution of gum arabic (3) or Klucel® EF (4) with the addition of Tylose® to adjust the consistency and an alkali to adjust the final pH if necessary.

Recipe by Cera Colla

We prepare the wax milk by boiling in: • 1 liter of water • 60 grams of beeswax So 10% • 40 grams of carnauba wax Wear a mask. When the liquid is boiling, remove it from the heat to incorporate • 10 to 15 grams of Alcali like triethanolamine, ammonia, sodium carbonate, etc.. dissolved in a few water. • It foams strongly, we put back on the heat until the end of the effervescence. Leave to cool, off the heat, while continuing to stir from time to time until the Cera-Colla is lukewarm, then it is transferred to a 1.5 liter flask, because we must add the resin dissolved in essence (1) or skin glue (2), in order to emulsify and give the final mixture sticky and adhesive properties that cold wax alone does not have enough.

2

Melt the wax in hot water : 80-90°C

3 After adding the ammonia, put back on the heat

1

Weigh the waxes and ammonia

4

Continue to heat the saponified wax a few minutes.

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THE CERA COLLA

Pour the saponified wax into a container and let cool. You can also remove the water from it and make cera colla breads that will be kept in full and stoppered bottles, or you can create paints and then put them in tubes to give body to the pasta. This is impossible with liquid wax, otherwise it would have to be added a load such as quartz powder or kaolin. This helps maintain the purity of the pigments and the paint. See 6 and 7 below.

8

5

Pure Cera Colla potted to keep it indefinitely. When using, add water and then part of the binder, resin or skin glue or 30% casein base (see casein).

(1) Resin solution in essence : 50 g of mastic resin dissolved in 100 ml of turpentine or aspic spirit See mastic resin solution N ° 1 30% of this mixture is added to the cold wax, then vigorously shaken, the binder is ready.

6

The cera colla is placed on a marble to allow the water to evaporate in order to keep it in a pot.

Turpentine

7

Cera colla rolls after 24 hours, left to dry out of direct sunlight and stored in a jar or air-free bag. The cera colla is rehydrated at the time of use. Mastic resin solution N ° 1 Mastic from Chios


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THE CERA COLLA (2) Solution of skin glue at 30% or 30% casein base for 1 liter of Cera-Colla. We make the 8 gram skin glue as follows :

30 cl of water in which we dissolve 15 grams of Klucel E

Pour 30 cl of water into a saucepan, add to it 24 grams of skin glue in plate for the best qualities of skin glue or in powder for ordinary qualities. The glue is left to swell in water for 12 hours then the water is heated, the glue is dissolved (do not boil), before the liquid cools, incorporate the melted glue into the wax milk then put in a bottle and shake energetically, the binder is ready.

Skin glue plates

Hide glue

(4) 30% Klucel's solution :

powdered casein

5 g of triethanolamine to correct the pH if necessary We add this solution to the wax milk, we test its adhesion and consistency, in which case a little powdered tylose is added directly to the binder and left to swell.

casein base KLUCEL® EF cellulose ether

water

3) 15% gum arabic solution: 10 g of gum arabic dissolved in 15 cl of water 15 cl d’water Let the gum swell in water for 48 hours without heat, then add a dash of camphor as a preservative. Filter through cheesecloth. Add this solution to the Cera-Colla. Make a test on a piece of paper at 300 g / m2, if the mixture is too rigid, add 2 to 5 cl of glycerin or 20 drops of silicone antifoam.

glycerine

gum arabic swelling in water

Antifoaming

Gum arabic powder. the gum becomes thinner after exposure to light.

pH meter

triethanolamine

All of these recipes can be stored indefinitely, in full and stoppered bottles, protected from light and frost. Cera-Colla is a very durable painting technique on all rigid supports, such as wood, concrete, plaster, metals, ivory, thick cardboard, etc. ... It mimics the smoothness and structure of oil paint to perfection, but with a more matte texture. The supports are prepared by covering them with Cera-Colla emulsified with mastic varnish. We wait 24 hours to start painting. The pigments are ground in water using a mortar and pestle, then they are amalgamated with the final binder, it is possible to tube these paints, however some pigments can set together quite quickly. The use of small capacity containers seems to be the best containing ground material, the same as for the encaustic. The paints can be varnished with Cera-Colla with a solution of Tinuvin 292 and 900 at 1% dissolved in Solvesso 100 or xylene or else just rub the surface of the paint with a soft lint-free cloth in order to polish the wax and give it a satin appearance.


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CERA COLLA COLOR CHART

Cera Colla skin glue color chart, left in the dark for 21 years from 2000 to 2021. The pigments are intact, they are still just as bright. From left to right and top to bottom: 1.Titanium white, Yellow ocher, Limonite N ° 1, 4.Natural Cyprus Shadow Land, Manganese brown, Vine black, 7. Naples yellow, Orpiment, Nickel titanium yellow, 10.Strontian yellow, Verdaccio yellow, Verdaccio dark greenish, 13.Italian dark ocher, Pozzuoli red oxide, Cochineal carmine, 16.March violet, Azurite N ° 1, Natural malachite. Other pigments on the right page. The pigments retain their hues after drying, they would tend to increase in tone, but this is certainly due to the matt character of the wax which gives contrasting values to the films of the wax-bonded paints.

Paints grounded with Cera Colla keep very well and for a very long time. This tube of Blue Ceruleum à la cera Colla is from 2003, it looks like it has just been grounded and put into a tube. Tube of cera Colla Cadmium Red 2003


PALETTE - PIGMENTS CHOSEN FOR THE CERA COLLA With the 18 pigments from the color chart on the previous page, here are 20 additional colors to add to the list of pigments that can be used with the cera Colla. All natural iron oxides, spinel pigments and high performance pigments can be used with Cera Colla. Pigments that are resistant to the relative alkalinity of the binder should be chosen.

Titanium white XSL

Zirconium White

Indian yellow imitation

Cobalt Blue

Cobalt Blue turquoise

Ultramarine red

Hostaperm Pink PR122

Emerald green

Cobalt violet

Heliogen Green

Bismuth yellow

Priderite yellow

Ultramarine

Heliogen Blue

Irgazin Red

Red ocher

Very light ocher

Manganese gray

Intense Manganese Brown

Spinel black

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BUCKETS WATERCOLOR

The word watercolor is borrowed from the Italian "acquerello" diminutive of "acqua", water. The work can be done in a very thin pencil (4H) and then it is enhanced by a contribution of paint that moves it away from graphic and plastic expression, to bring it closer to pure pictorial expression. Watercolor is the least solid of all paints because of its finesse and little material: it will have to be exposed out of light or under UV-resistant glass, out of oxygen. Favor very fine and light pigments. This is the technique of transparency par excellence.

Less fragile watercolor recipe, with ethylcellulose binders such as Klucel HF and M or Tylose MHB 30,000 in solution in cold water so : Watercolor with EthylCellulosic gums 30 g of Klucel® or 30 g of Tylose® or 30 g of CarboxyMethylcellulose + preservative 1 liter of cold water or well below 38 ° C 15 drops of beef gall + 5 gts of camphor To make plastic cups add 20 g of tragacanth gum + 15 drops of glycerin The addition of glycerin is not necessary due to the high plastic qualities of Klucel, but you can add a few drops of PEG for the glide. Make sure that the preservative is stable and non-yellowing, as well as any other added adjuvants.

2 tragacanth gum

Flower honey

distilled water

Amalgamate the pigment with the water and the surfactant then add the honey

3 1 Glycerine

Camphor

Very clear tree gum

Weigh 5 g of pigment here hostaperm pink PR122 Add tragacanth and gum arabic solution

Recipe N ° 101 of Watercolor in Bucket

I use the same binder as the watercolor tube, but I add glycerin and less gum arabic. Added during the grinding ox gall or Ecosurf EH6 with synthetic organic pigments. FOR A LIGHTWEIGHT PIGMENT LIKE HOSTAPERM PINK PR122 5 g of pigment grounded with 15 cl of pure water

4

15-20 drops of honey + 5 drops of glycerin

The paint is ready to be put in a cup using a shaper plastic of the bucket width

15 drops of tragacanth solution (2) 8 drops of Gum Arabic Solution (1) Half empty containers for watercolor and gouache, but any container can be used as a container as long as it is waterproof. I bought some of them from known suppliers, but you can find in glassware stores square containers or the like that can be used for this purpose.

Logwood black bucket

5

cochineal buckets

Watercolors : epidote and hostaperm red PR122 (quinacridone) of magenta tint (named lacquer by the suppliers)


347

WATERCOLOR HONEY TUBE RECIPE Recipe N°100 of Watercolor in tube

The pigments are ground ultra fine with camphorated water and with honey on the marble then they are amalgamated with a solution of gum arabic and a solution of gum tragacanth according to the density of the pigment used, so that it does not build up. not separate in the tube. Add xanthan gum to make the watercolor thicker, while also remaining transparent or sepiolite to give it more strength (just like Laponite). Add 10% beef gall or 2 drops of ecosurf EH6 with the organic pigments. You can add tylose or klucel, but also starch or dextrin to give body and PEG 1: 2 to glide in the water. See Suppliers 39 for empty tubes. We prepare 2 solutions with 3 different gums

1

SOLUTION N ° 1 GUM ARABIC AND XANTHAN 5 g tree gum or gum arabic In 100 g of distilled and camphorated water 1 drop of honey per g of pigment when grinding 5 drops of xanthan gum 1: 9 in water 5 drops of Glycerin And this other solution No. 2 to prevent the heavy pigments from separating in the tube, but also to make solidified watercolors, and why not also, pastel sticks.

2

SOLUTION N ° 2 TRAGACANTH 4 g of wet tragacanth with a little of alcohol and swelling for 24 hours in 105 grams of distilled and camphorated water Filter the 2 solutions with a silk stocking then grind the pigments in distilled water on the marble with all the honey, add the gum arabic solution then at the end the gum tragacanth solution to make a creamy paste in order to put that here in a tube. FOR A HEAVY AND EARTHY PIGMENT LIKE EPIDOTE ADD MORE HONEY Pigment: 20 g + pure water QSP grinding + 25 drops of honey added during grinding Gum arabic solution: 10 drops Tragacanth gum solution: 20 drops

See the table below, as the pigments all have a different density. With this short list you can predict the density of a pigment according to its family, eg. for heavy pigments, earths, ochres, etc. Tip: after grinding, let the water evaporate a little in order to put a pasty watercolor in a tube DENSITY LIST OF PIGMENTS Pigment Density g/cm3 Titanium White 4,26 Lithopone White

4,3

Cobalt blues

3,83

Ultramarine blue

2,34

Prussian blue

1,83

Jarosite

3,2

Yellow ochres Vanadium yellow Zinc Yellow Titanium Nickel Yellow Priderite Yellow Green earth Malachite

3,49 à 4,30 6,7 3,4 à 3,46 4à5 4,2 à 4,8 2,79 3,7 à 4,1

Cobalt Green Spinel

4,53

Mars orange

3,7

Titanium Orange

4,4

Paliotol orange

1.77

Isoindole orange

1.79

Pink Hostaperm E

1,47

IRGAZIN Red

1,5

Iron Brown Zinc

4,60

Charred Shadow Land

3,64

Cobalt Violet

4,2-4,5

Ultramarine Violet

2,35

Lightweight and / or organic pigments such as cochineal, Prussian blue, Irgazin, Paliotol, Isoindole, Hostaperm require 15% soil. gum arabic, + 5% gum tragacanth

Manganese Violet

2,70

Manganese Gray

5,026

For heavy pigments, such as vanadium, cobalt, vermilion, iron, manganese, etc., use 15% tragacanth gum solution: it prevents the pigments from separating from the binder in the tube + 10% Arabic gum

Manganese black

3,125

Preparing watercolor is similar to preparing pastel sticks, take advantage of this when making watercolor to make a pastel stick at the same time, since you have tragacanth already prepared.

Graphite

2,0 à 2,36

Spinel Gray

5,4

Black Spinels

4,5

Black magnetite

5,18


348

MAKING TUBES AND BUCKETS OF WATERCOLOR PAINT

3

1 Grinding with pure water and honey, on marble, pigment, here ultramarine red, add the binder at the very end to mix it well to the ground pigment paste: the watercolor is ready at this time. See on the DVD for the complete procedure in pictures.

Preparation of the dough to put it in a flexible aluminum tube as below with the epidote, a unique pistachio shade.

4 5

2 We can add 2-5 drops of Glycerin in addition to honey

Here I chose the epidote, an earthy pigment, very hard to grind, to determine the maximum amount of honey and binder to be added to the system with the heavy pigments, and I chose Hostaperm red, PR122 for the light pigments. I put the watercolor in a tube with an acetate sheet and I also made pots: you have to add more honey with the earthy pigments and ochres, a little more than one drop per gram of pigment in order to amalgamate the pigment and the binder well and to be able to resume the watercolor indefinitely with plenty of water. It is necessary to add a surfactant (beef gall, Ecosurf EH6) with the synthetic organic pigments which do not have a positive charge, so they flocculate very easily, they have trouble mixing with water and they create buds pin within the paint film. The addition of Glycerin serves to plasticize, but Tylose®, very plastic, can also fulfill this function just like laponite®.

Materials for making watercolor in tubes and pots then test on paper of epidote paint, a very subtle pistachio tint


349

PALETTE - PIGMENTS CHOSEN FOR WATERCOLOR

Zinc white

Lithopone

Titanium white XSL

White Gofun Shirayuki

Black from vine

Atramentum

Gray spinel

Gray from Mels

Brown ocher from Elba

Sepia

Pyramid yellow

Hansa yellow PY74

Bistre

Lamp black

Zurs Brilliant Brown

Praseodymium yellow

Hansa yellow PY3

Pale Cyprus Ocher

Indian yellow PY150

Paliotol orange

Vermillion

Hostaperm Pink

Orange glacis

Blue ceruleum

Irgazine Red

Curcuma

Jarosite

Red cabbage

Smalt

Blue Heliogen

Lapis Lazuli

Green-grey synthétique

Heliogen Green

Nettle

Emerald green

Chrysocolle

Cobalt violet bright

Gamboge

Madder

Blue from Prussia

Victoria Green

Ultramarine red


350

MODERNE GOUACHE Gouache is a painting technique made by mixing gummed water, a filler, a little plasticizer, a preservative and pigments. The word gouache derived from the Latin "aquatio" action of watering is borrowed from the Italian "guazzo", place where there is water and attested as a painting term since the first half of the 16th century by Saba da Castiglione, religious, scholar and Italian humanist (Milan, 1480 - Faenza 1554), we say "in guazzo". There is also the French term "gouacher", to paint with gouache (Delacroix, Journal). Gouache has its origin in ancient Egypt, proven by analyzes of funerary portraits from the Fayum showing the use of tree gums in addition to encaustic. Its use in India and Persia is also attested. It was rediscovered in France in the 17th century along with watercolor and pastel. Gouache was used mainly for preparatory drawings for oil works. In fact, after drying the gouache, looks like oil paint, it takes on a pearly tone thanks to the white it contains. It was a technique popular with Italian decorators of the 16th and 17th centuries, as well as artists who used it to create highlights on their ink drawings. I saw many master drawings in the Louvre, enhanced with gouache. But the general diffusion of the technique is due to France of the 18th century. In the 19th century, the technique was generalized due to its use in the production of advertising posters to become a technique widely used by schoolchildren in the 20th century, which in my opinion depreciated the technique, which was basically a technique called "noble", used by artists. The quality of modern artisanal gouache is superior to any other commercial paint known as "gouache", because the ingredients and pigments are purer, and we can dose the loads at our convenience.

As for watercolor, the work can be done with a thin pencil (2h) then enhanced by a contribution of paint, but it can also be the subject of a mixed technique with any other technique of aqueous, wet or wet painting. dries like pastel. This is the technique of opacity, solids and highlights, because it contains an opaque filler like talc, kaolin or quartz powder, this is the main difference from watercolor.

Binder Damour N ° 1 for Modern Gouache

The preparation of gouache requires putting tragacanth, gum arabic and a little albumin in solution. To make cups, add glycerin or honey to the dough: so 5% of the total volume of the paint. Gouache binder recipe is for a base binder to swell for 12 hours 10 g of tragacanth 5 g arabic gum 2 g of powdered albumin 40 cl of pure distilled water 126 g of talc or kaolin 20 drops of sodium benzoate 10 drops of Antifoaming After 12 hours add 10 to 30 g of pigment depending on its coloring power add 5 drops of beef gall only for rebellious supports You can make gouache with synthetic binders such as Klucel HF and M or Tylose MHB 30,000 in solution in cold water either Synthetic binder for gouache 50 grams of Klucel or Tylose dissolved in 1 liter of water

Making the gouache insoluble with albumin or shellac Gomme adragante

Gomme arabique

Sodium benzoate

If you want to insolubilize and thus make gouache or any other gum-based paint indelible, add 5 to 10% of pure liquid egg white or powdered albumin to the binder. You can also use 10% shellac, making it miscible with water by saponification with a base such as soda, borax or ammonia.

Glycerine

Water

Camphor


351

BUCKET OF GOUACHE Gouache in bucket

back of an ultramarine Bucket 2 cm thick

The pigments are ground very finely with water and then amalgamated with a solution of tragacanth, kaolin and glycerin or honey. Glycerin is added to give the cup a hydrophilic character after hardening. Recipe Gouache Bucket 30% albumin-free gouache binder Kaolin or Talc: 30% of the total volume Glycerin: 5 to 15% of the total volume depending on the hydrophilicity of the pigment, up to 20%. Pigment from 20 to 30% depending on the coloring power of the pigment 10% pure water The pigments are ground on marble or in a mortar, first with pure water, then the gum solution and the filler are added to make a creamy paste in order to put it in a cup, this is the same operation as for the watercolor in cup, the difference is the addition of Kaolin or Talc. To maintain the cohesion of the block and give it a wet character, more glycerin is added to the cups, i.e. 5 to 20% of the total volume, a value to be evaluated according to the hydrophilic nature of the pigment, a synthetic ultramarine blue which is very greedy for water will require more glycerin.

Bucket of ultramarine on the face side, it seems hard and insoluble, but the glycerin contained in the mass makes it possible to restore its cohesion to the paint when water is added with a brush, which is why it is necessary to provide to incorporate enough glycerin in the binder if you plan to make very thick tablets as above. For the record, I left this bucket 10 years in the dark to see how it would behave, in fact it's as if we just did, however consider adding a curator.

For heavy pigments, more tragacanth gum solutions are used, which also prevents the pigment from separating from the binder if one wants to tube the gouache. See the density of pigments on page 349, because each pigment has its own.

1

Put the gums in a jar

2

3

Pour the water over the gums

Let the gums swell for 12 hours

4

After 12 hours, put the binder in a blender


352

5

7

PREPARING THE BINDER FOR THE GOUACHE

6

Pass the binder in a blender to ensure its cohesion, then add at the very end 5 drops of Antifoaming

Broyage de 5 g de Manganese Gray avec 10 ml d’water

10

Gouache Manganese Gray

8

Here is the basic binder ready to use for painting with gouache

Laissez s’évaporer l’water ou ôtez-la avec une seringue, avant d’ajouter le talc puis le liant

Here is the basic binder ready to use for painting with gouache

9

Ajoutez une charge comme du talc ou du kaolin avec le liant et le pigment

Comparaison des liants : aquarelle à gauche et gouache à droite, avec le même pigment Manganese Gray. Remarquez le caractère plus profond et vif de l’aquarelle tandis que la gouache est plus sourde, plus opaque et mate, cela est dû à l’ajout de talc ou de kaolin.


THE "KLACHE" UNIVERSAL AQUEOUS BINDER

353

Pure albumin powder in excess and pigment without glycerin To make crackle paints

Victoria green and pure albumin with a little Glycerin

Manganese gray and gouache binder Damour N°1 On the left = without addition of fillers = Pure binder alone = Watercolor effect On the right, addition of Talc or kaolin and two drops of glycerin as plasticizer = Gouache effect

Universal aqueous binder N°1 named "Klache" Here is a binder that I formulated and named "Klache". Mix: • 10 g tragacanth • 5 g arabic gum • 2 g of powdered albumin or 1 liquid egg white, if you want to make the binder indelible. Go to the blender with • 40 cl of water, in which we add • 2 drops of Antifoaming (this is what makes the binder white and opaque at the end) • 20 drops of sodium benzoate. Leave for 24 hours for the gums to dissolve thoroughly, the older the binder the better. If you don't have a blender, let the gums soak for 2 days. The ideal would be to prepare well in advance and to let sediment the pure gum arabic solution, because I noticed that a brownish sediment settles at the bottom of the container after a few weeks, then poured the upper part into a new bottle. Add camphor, a preservative, as in the picture of gum arabic solution or sodium benzoate, then add or not add glycerin after grinding the paint if you want to make a more paint or less matt or more or less dry and rough. Then I mix a little binder and a little pigment depending on the opacity and depth of tone I want. Klache is a very practical universal binder, by dilution we obtain watercolor. If we do not add talc or kaolin, or albumin with the pigment and the binder, it is watercolor, if we add only albumin and gum arabic it is a kind of indelible liquid enluminure, adding talc or kaolin gives gouache.

Klache, for making watercolor or gouache

Camphor. By letting camphor stay for a long time in pure water, camphor water is produced which serves as a preservative.

Gum arabic solution Note the sediment after a few weeks this is why it must be filtered or recover the part that floats


354

PALETTE - PIGMENTS CHOSEN FOR THE GOUACHE

Zinc white

Smoke black

Praseodymium yellow

Indian yellow PY150

Irgazine Red

Red cabbage

Heliogen Green

Lithopone

Van Dyck Brown NBr 8

Hansa yellow py3

Pale Cyprus Ocher

Isoindole orange

Blue Heliogen

Nettle

Titanium white XSL

Beaune Gray

Pyramid yellow

Zurs Brilliant Brown

Paliotol orange

Ultramarine bright

Emerald green

Barium white

White Gofun Shirayuki

Atramentum

Manganese gray

Brown ocher from Elba

Jarosite

Hansa yellow PY 74

Gamma mars yellow

Titanium-Nickel Yellow

Sepia

Iron and zinc brown

Red ocher of Morocco

Hostaperm Pink

Orange glacis

Blue from Prussia

Blue Spinelle

Cobalt Blue Greenish

Chrysocolle

Victoria Green

Cobalt violet bright

Ultramarine red


355

DRY PASTEL POWDER PAINTING TECHNIQUE

gum tragacanth binder

Dry pastel comes in the form of cylinders or squares a few centimeters in length (usually 5 to 8 cm), in order to have them well in hand. The mixture of water, tragacanth and camphor as a preservative constitutes the binder.

cherry gum

NEVER USE TOXIC PIGMENTS It is imperative to use harmless pigments, because the pastel sticks remain pulverulent on the surfaces, the fact of squeezing them in the fingers, in the long run the sweat risks dissolving fine particles of pigments and entering by this way in the body. Rub your hands with a barrier cream "Bariederm" from URIAGE, it will protect you at least in case, however it is advisable to wear gloves.

1

Binder recipe for Pastel

Make a small pile with pigment and pour water in the center to grind the paste.

3 grams of tragacanth inflate 24 hours in 50 cl of distilled water <10% cherry gum solution 1 dash of camphor or sodium benzoate 5 drops of glycerin

2 Add 10% kaolin, chalk or talc. Pour the binder and continue to grind the paste.

Raw Tragacanth

Tragacanth solution

Liquid metering and water

Sodium benzoate

3

Camphor

Glycerine

Binder with Pastel left 10 years away from light, it is still active.

Allow the water to evaporate, while the dough becomes ductile and firm, so that it can be prepared and placed in a mold.


356

DRY PASTEL POWDER PAINTING TECHNIQUE

binder with tragacanth + 10% tree gum

4

Make a pile of the dough (Elba brown ocher) to allow the excess water to evaporate, to mold it.

5

6

7

If the stick is too crumbly, we crumble it on the marble, then add a little binder and pure water, we remake the stick then we mold and unmold. Each pigment requires a different proportion of binder that will be determined empirically. To achieve gradations, it suffices to take the pure pigment to which is added 10 to 30% kaolin or talc in proportion according to the desired shade. The pastels are wrapped in 10 baking paper as opposite or with tissue paper to avoid repeated contact with the skin.

Bring together the dough obtained in order to mold it easily. Elbe brown ocher pastel stick test

Coat a mold with glycerin so that the dough does not stick.

The dough is introduced into a cylinder or a hollow half cylinder, made of glass or PVC to make the pastel stick. You can use transparent plastic of the test tube type, but you can also create logs without a mold, simply by forming them by hand on the marble. It is left to dry for 24 hours.

Transparent PVC mold

8 The next day we easily remove the pastel stick from its mold. It is ready to be used.

9

Elbe brown ocher pastel stick test

URIAGE ® Bariederm protection cream This cream provides some protection against allergic agents and chemical attacks from pastels and paintings. However, it does not replace a pair of gloves. Wearing gloves is the best protection.

Pastel made in half with handcrafted pastel sticks for skin tones and background. For fine details with Carbothello® pencils from Stabilo ©.

"The Virgin and Child" Pastel on paper 65 X 50 cm According to Simon Vouet. © 1993 David Damour Private collection France


PALETTE OF NON-TOXIC PIGMENTS FOR DRY PASTEL

357

Do not use pigments containing heavy metals such as lead, cadmium, mercury, molybdenum which are toxic. Natural ochres, earths and synthetic iron oxides are good pigments for pastel. Spinel pigments, PICS pigments, synthetic dyes are suitable and provide a very good color base. By mixing the 42 pigments of this color chart, with kaolin and between them, you will obtain more than 1700 shades.

Carrière du Revoi's Chalk

Kaolin

Zinc white

Lithopone

White Gofun Shirayuki

Alba Albula

Spinel black

Black iron oxide

Black from vine

Gray onyx

Beaune Gray

Jarosite

zinc yellow

Nickel titanium yellow

Brown ocher from Elba

Hansa yellow

Yellow ochre

Indian yellow PY150

Ultramarine bright

Ultramarine extra dark

Blue Maya

Sanguine

Herculaneum red

Morocco Red ocher

Mars yellow orange

Red oxide pouzzolles

Blue Heliogen

Blue from Prussia

Iron and zinc brown.

Irgazine Red

Zurs Brilliant Brown

Iron oxide brown

Heliogen Green

Chromium Oxide Green

Violet ultramarine reddish

Cobalt violet bright

Blue spinel

Emerald green

Ultramarine red

Blue Indanthren

Victoria Green

Mars violet


358

PAINTS WITH SILICATE BINDERS Silicates through the ages

For more than 600,000 years, humans have used silica in the form of a flint pebble which is a cryptocrystalline silica also known as Basalt. In this form, the crystals are so fine that they are indistinguishable except under a microscope. Their industrial use dates back to around 1818, but references to the manufacture of sodium silicate are even older and date back to the ancient Phoenicians. Alkali silicates were produced by the ancient Egyptians ~ 6000 years ago, where sodium silicates (and possibly potassium too) were made by fusing sand, quartz and soda or potash, naturally produced from combustion process. It is also possible to believe that alkali silicates were used in frescoes and wall paintings found in the ruins of Pompeii and Herculaneum which were preserved from the eruption of Vesuvius in 79 AD. J.-C. The first description of the solubility in water of a molten mixture of flint pebbles with potash was transcribed in a posthumous work "Ortus medicinae" by Jean Baptiste Van Helmont (1580 - 1644), a Brussels physician, " to fuse the glass with an alkali, then to precipitate the silica by means of an acid ", he named the silica" quellem ", thinking to have discovered a new elementary earth; we also owe him the introduction of the word "gas" in the vocabulary of chemistry. A Dutch German chemist, Johann Rudolph Glauber (1604 - 1670) obtained in 1648, a thick solution consisting of a molten mixture of sand, pebbles of flint or crystalline quartz with potash which he named "liquor silicum" for stone liquor. Glauber recommended its use as a curative agent, for the production of liquid fluxes for melting metals and for glazing in buildings (Furni Novi Philosophici, Amsterdam 1648-1650). In 1768, the famous German poet, Johann Wolfgang von Goethe was also interested during his alchemical studies with potassium silicate. Despite a number of references in the literature, the development of water soluble silicates really began around 1825 when Johann Nepomuk Von Fuchs (1774-1856) a German chemist and mineralogist, studied the industrial production of soluble potassium in water. water, which he named "waterglasses" for "liquid glass". This exceptionally resistant binder was noticed by King Louis I of Bavaria who was looking for a paint that was stable in the harshest temperatures of Germany, similar to Italian lime plasters. Potassium silicate paints were born. Von Fuchs came up with solutions that could be used as adhesives, cements, fire retardant paints, to seal porous stone and as binders imitating fresco. He also invented the name of "stereochromy", a mural painting process allowing the chemical fixation of pigments, "The basis of stereochromy is silicate of potash (...) The finished paintings, we cover them

with a dissolution of silicate, and this species of absolutely colorless varnish (...) guarantees them from any atmospheric influence (Chabat1881). Von Fuchs observed the reactions of potassium silicate solutions with various pigments and tried to explain in terms of chemistry such phenomena than the precipitation by alcohol, the efflorescence of sodium carbonate in a silicate solution which contains potash as the main base and the preparation of solutions with a high level of silica by dissolving precipitated hydrated silicas in silicate solutions obtained by dissolving the vitreous material by heat in the oven. He also proposed silicates as agents for direct cleaning of laundry and mixed with soap, as a reagent. yews in textile dyeing, for brazing and welding fluxes (mixture of chemicals to ensure good wetting of the alloy for the parts to be assembled) and as fertilizer. Therefore silicates have been available on the European market as well as in the USA since 1855. Modern ecological concerns make silicates the materials of choice because they are healthy, easy to use, and very stable.

Properties of alkali silicates for paints and for building mortars Silicate coatings were generally 2-component coatings, sometimes referred to as 2-K coatings, they have been used in Europe since the late 1870s for architectural coatings. Ethyl solvent-based silicates were adopted out of concern for and reducing the VOC content of coatings, although water-borne silicates are popular with painters and are used in a number of areas including: • The impregnation of the concrete to make the surface hardening • consolidation of weathered natural stones • As a barrier against humidity, in particular against rising damp when mixed with paints. Silicate emulsions were introduced to the market in Europe in the 1960s, they have been at the forefront since the 1970s. With long term stability of exterior coatings based on 2-K silicate paints as well as the advantages of organic emulsion paints, there was a desire to make it easy to use by developing a one-component system, i.e. 1-K which has the same properties as mineral paints as well as ease of production, ease application and storage stability.

Properties of 1-K coating systems

• Quick and easy implementation • Good rheological behavior • Stability of the binder and the filler / pigment system against re-agglomeration • Storage stability and shelf life> 1 year • Low degree of sedimentation and syneresis (decrease in the volume of the solid mass and gradual expulsion of the constituent liquid) • Good dispersibility • Simple application properties


PAINTS WITH SILICATE BINDERS • Good diffusion in the substrate for a • Strong adhesion and surface hardening • Good retention of the pigment on the substrate • Perfect hardening without chalking • Good weathering stability • Water vapor permeation The above properties are obtained by properly using the systems formulated and based on binders of stabilized potassium or lithium silicate, mixed with a small proportion of alkaline emulsion and stable organic resins, mixed with pigments and additives. appropriate. Sodium silicates are hygroscopic and generate efflorescence unlike others. Silicate emulsions are formulated by adding fillers duly selected and based on calcium carbonate or silica. Waterborne alkali silicates are believed to be harmless to the environment on the basis that: • Hardened systems are silicate based and are therefore very close to what already exists in nature. • There is no significant health risk during the application in pasty form. • They must not have any allergenic material • These are zero VOC products • They provide a good estimated lifespan compared to the coating and the substrate In nature, almost 95% of the earth's crust is made up of quartz and important silicates.

Constitution of silicates

• Plagioclase: albite (NaAlSi3O8) and anorthite (CaAl2Si2O8) = 42% by volume • Potassium feldspars and orthosis KAlSi3O8 with traces of Na; Fe; Ba; Rb; Ca, = 8 to 22% • Quartz (or silica) SiO2 = 18% • other more complex silicates include Amphiboles at 5% by volume and 12% other silicates. Silicon compounds are also found in the hydrosphere (areas of a planet where water is present), mainly as dissolved silica. Inorganic silicate paints are chemically bonded with the mineral carrier and petrified with the substrate for an insoluble combination after evaporation of water, reaction with carbon dioxide and moisture in the air. This process is called "silification" also known as "petrification". Silicate mineral paint has many advantages such as high durability due to its inorganic composition, resistance to rubbing and abrasion, high permeability to water vapor, resistance to mold and growth fungal due to its alkalinity. The paints are odorless and nonflammable, free from solvents, biocides and environmentally friendly. Their main drawbacks are their high water absorption and their low flexibilities and therefore a lack of plasticity, which is why various adjuvants are added to them.

359

Pigments usable with silicate binders

The pigments that can be used are exactly the same as those used in fresco, such as iron oxides and high performance pigments as well as pigments supporting basic binders such as cera colla. Check the pH of the binder [131]

Modern recipe for silicate binder paint

Here is a subtle mixture of binder to make a silicate paint on wood, imperatively prepared with a coating of at least 1 cm based on carbonate fillers (chalk, powdered marble, dolomite) because the liquid silicate must react with the carbonates present in the support to forming a porous silica. • 250 g of potassium or lithium silicate • 158 g of water • 1 g xanthan gum • 80 g of polyethylene glycol • 80 g of BTMS emulsifier (at aroma-zone) • 3 g of dispersing agent • 100 g of talc • 270 g of kaolin • 3 g of Antifoaming • 2 g of Laponite • 10 g of very fine silica or colloidal silica • 10 to 100 g of Pigment depending on the coloring power Check the pH before adding adjuvants for perfect compatibility. It is recommended to use in silicate paints for interiors stabilizers, quaternary amines and stabilizers derived from amines that considerably increase the quality of these paints, they make silicate-based systems interesting, also to achieve paintings with a matt aspect to the appearance of fresco on a mobile support such as wood. These paints are zero VOCs. Emulsion paint refers to the type of binder used in painting. Simply put, it is the binder that allows paint to stick to the surface of substrates. Emulsions (dispersions) are liquids, with small polymer droplets distributed evenly over the entire volume (these products are made similar to emulsion paints) and they remain stable by adding appropriate stabilizers to the system. Products with a water / polymer ratio of around 1: 1 are generally used. During the process of drying the film, the water evaporates, so that the polymer droplets get closer and closer until they form a compact plastic film. The paint film hardens and binds all elements in the paint and to the surface. In formulating and stabilizing these paint systems, however, what is suitable for interior application may not necessarily work for exterior application. For the exterior, the silicate will be used with hydrophobic agents and then fixed with a suitable fixative available from the supplier of the potassium or lithium silicate.


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PAINTS WITH SILICATE BINDERS Modern silicates

One of the reasons for the early development of soluble silicate is due to the relatively simple process for making them. Sodium or potassium silicates are produced by melting sand (natrite) sodium carbonate Na2CO3 or potassium carbonate K2CO3 at 11001200 ° C. The glass thus obtained is dissolved with high pressure steam, it finally forms a bright liquid, slightly viscous. Liquids can also be spray dried to form hydrated powders. Dissolved or liquid silicates are the most popular commercial form for paint applications as a binder. As a brand, there is Syton © X30 and W30 as well as limasol © as a binder in aqueous dispersion. Potassium and lithium silicates are unique in that they can undergo three very different chemical reactions. These reactions are defined like this: 1.hydration / dehydration 2.Gelling / Polymerization 3.Precipitation These reactions allow the silicate to act as a binder, matrix binder and chemical binder. The silicate can thus cause an agglomerated material to adhere or stick to a support by one or more of these chemical reactions.

1.Hydration / Dehydration

When the water is removed from the liquid, the silicate gradually becomes more viscous. Removing a relatively small amount of water transforms the silicate liquid, thus becoming a glassy film. Liquid silicates with a high ratio of 3.2 are best suited to act as a binder. The lower alkali content of the silicate at a ratio of 3.2 has less affinity for water and can thus harden faster. After drying the bond is less sensitive to moisture absorption, but to achieve more complete water resistance some degree of heat or chemical adjustment must take place. When using potassium silicate as a film-forming binder, it is sometimes advantageous to include a small amount of surfactants compatible with the silicate (eg an anionic or nonionic agent). Laboratory studies have shown that the inclusion of a small amount of surfactants can reduce the surface tension of the silicate in the proportion of 3.2 from 77 dynes to 40 dynes. Reduced surface tension is an advantage that allows easy application of the binder as well as the possibility of applying a thinner layer of silicate paint, which will help to decrease the drying time.

2.Gelling / Polymerization

Gelation / polymerization reactions occur rapidly when the pH of the liquid silicate drops below 10.7. The crosslinking of certain species of silicates makes it possible to form polymers. Although the bond formed by the polymerized silicate is not as strong as the bond formed by dehydration, it has a high degree of water resistance. This reaction can play a role in agglomeration, where the surface of the agglomerated material is acidic or the agglomerated

material is exposed to an environment rich in CO2. The dosage can be adjusted so that the silicate induces gelation / polymerization. Certain adjustment agents such as acid salts, organic acids, esters or carbonates (lime) are used. The inclusion of a silicate polymerization aid is quite common. Once again, a silicate ratio of 3.2 is perfectly suitable for promoting the gelation / polymerization reaction. The low alkali content of this silicate ratio of 3.2 allows faster neutralization. Soluble silicates react almost instantly with multivalent metal cations to form the corresponding insoluble metal silicate. Examples of common metal ions which are reactive with silicate include: Ca + 2, Mg + 2, Zn + 2, Cu + 2, Fe + 3, etc. ... If the material being agglomerated contains a significantly higher amount of positive cations on its surface then the silicate can act as a chemical binder. Volcano ash and ammonia are examples of materials that can chemically bond with silicate. Generally speaking, a high silicate ratio of 3.2 is most suitable for chemical bonding, as it represents the part of the siliceous silicate which reacts with cations.

Silicate Sticks or Sticks Recipe

They are formed by mixing silicate, 95 ° ethyl alcohol, chalk (a filler) and pigments. 1. Measure out 50 ml of sodium silicate solution and pour it into a small plastic or glass container, as silicates cannot withstand iron and chrome objects. 2. Place 12.5 ml of ethyl alcohol in another plastic or glass cup. 95% ethyl alcohol works best, but you can try other alcohols, such as isopropyl alcohol. 3. Add the alcohol to the sodium silicate solution, not the other way around. wear a mask. 4. Using a circular motion, stir with a wooden or plastic stick until the substance formed thickens and becomes solid. 5. Place the polymer in the palm of your hand and knead it, then gently on the marble until it forms a log. Add the pigment and moisten with water then knead the stick to form a perfect stick. Add a filler like marble powder to brighten and give body. 6. Shape the dough into any shape you want, square or round. 7. Store the sticks in small zipped plastic bags or in a dry place. If they broken, it is possible to reform them. Silicon is a very interesting type of atom because, like carbon, it makes four chemical bonds and can branch out in many directions to form long chains. In sodium silicate, the silicon atom is bonded to four oxygen atoms. The ethyl alcohol molecule is very simple and has only two carbon atoms. When sodium silicate and ethyl alcohol are mixed, the silicate particles begin to bond with each other to form long chains.


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PAINTS WITH SILICATE BINDERS When ethyl alcohol (CH3CH2OH) is added to sodium silicate, two oxygen atoms are replaced by ethyl groups and crosslinking of the silicate chains occurs; it can also be mixed with water as a product. This process produces a rubber-like polymer. Unlike carbon, all silicon compounds are inorganic and their polymer unlike most other polymers is an inorganic polymer.

Potassium silicate

Silicate Sticks

Potassium silicate 28/30° pH = 11.7

SAFETY NOTE Wear eye protection and disposable plastic gloves, as sodium, potassium and lithium silicates are alkaline. Avoid all contact with skin and eyes. VOLCANIC ASH SiO2 = 74.28% + Al2O3 = 12.8%. it is a filler that can be used to make repairs, mastics with lime and cements mixed with silicates. Ash also has thermal insulation characteristics. It is not soluble in water and solvents. Melting point: 1260 ° C Specific weight 0.38 g / m3

Sodium silicate consists of sodium ions in pairs with silicate ions such as in (Na +) 2SiO32. The silicate ion can also form a tetrahedral structure, SiO44- with silicon at the center of the tetrahedron and an oxygen atom at each point of the tetrahedron. Long chain polymers are formed by joining these tetrahedra at 2 of each vertex to form negatively charged ions.

LITHIUM SILICATE Chemical Formula Li2O3Si. It is a consolidating agent for plasters, natural and artificial mortars and for all natural loads. Its qualities are identical to those of potassium silicate, but its consolidating power is better with mortars and its ability to protect against microbial invasions is greater for exterior paints. It can be applied directly to wet coatings. It is insoluble after hardening. Use only plastic or glass as the container.

Dry potassium silicate on glass detail

We can plasticize the potassium silicates called "glass water" with acrylic binders and we can also gel them with carbomers like Rohagit and Carbopol EZ2 (see my second book for the experiments in detail.


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ENCAUSTIC HOT WAX PAINTING Bleached beeswax in pearls

Encaustic is a hot wax or cold wax painting technique with the addition of liquid varnish or Dammar varnish as a binder. This is one of the oldest, most durable and strongest techniques, because wax has little fear of atmospheric agents apart from humidity and the associated alkaline salts.In good storage conditions, works made with wax are to some extent eternal. The use of hot wax dates from around 2000 BC. It is believed that his invention should be placed between the 5th century and the 6th century BC. AD and its application in painting in the 4th century BC. In AD, works of the Fayum in Egypt have been found, painted in the 1st and 2nd centuries, and strikingly realistic. The dry desert climate is no stranger to this excellent conservation. One of the advantages of encaustic paint is that it can be buffed to give it a finish that can range from satin to high gloss and is achieved by rubbing the wax with a soft, lint-free cloth. The wax can be sculpted, scratched, laid down, glued, dipped, cast, modeled, sculpted, textured, and combined with other materials [73] such as oleaginous binders (the wax must be saponified in this case) as well as pearlescent or iridescent fillers, etc. The paint cools almost immediately so that there is no drying time (this is the disadvantage of hot wax), it can always be reworked, immediately, the next day, in a week, in a year, in 10 years, when desired, it is the major advantage of the Encaustic.

Carnauba wax

Carnauba wax in blocks

Carnauba wax

Bleached beeswax in pearls

dammar resin powder

bleached beeswax in pearls

Sandaraque resin

Sandarac liquid varnish

Dammar varnish


ENCAUSTIC HOT WAX PAINTING The substrates

The best substrates for encaustic are rigid, absorbent and heat resistant surfaces. Non-resinous wood supports (maple or birch), heavy-weight watercolor paper of 300 gr/ m2 as well as intaglio papers, raw linen canvas mounted on wood or not then covered with an absorbent coating, plaster, stone, raw wood, terracotta and coated papers are all media that can receive hot or cold wax paint. Very fine Japanese papers that are rough can also make very good substrates for hot wax as long as they are well impregnated with pure wax before starting to paint, this technique is called: impregnation polish or paint. hot wax impregnation. An immutable rule says that the wax does not support smooth surfaces, they must be made rough or grainy with sandpaper just as with the dry pastel technique, which requires adhesion supports with rough edges or sprinkled with fine pumice stone or other texturing agents. The preparation of the rigid supports can be done using coatings formulated based on a mixture of quartz powder or any other filler and a quality skin glue or a resistant, non-putrescible binder such as a casein or Klucel-type binder. See adhesives and coatings.

Encaustic can be formulated in 3 ways I) Pure hot wax

You can use the hot wax alone without adding any other ingredient, just melt the wax in containers then add the pigment, stir with a bristle brush and apply the wax in this state. Once the work is finished, the wax is polished with a dry, lint-free cloth to make it shine if necessary. Soft substrates such as canvas or rigid substrates (wood) prepared with a dry plaster must be very absorbent and rough so that the wax adheres perfectly.

II)Hot wax with varnish BINDER FOR HOT WAX WITH VARNISH 8 volumes of bleached beeswax 1 volume of carnauba wax 1 vol of Liquid Varnish N ° 2 = 50 gr of Sandaraque in 100 ml of turpentine or aspic or Varnish Dammar N ° 1 = 50 gr of Dammar in 100 ml of turpentine or aspic We heat in a water bath on a hot plate or on an iron plate that we place on a heat source, small containers in which we put the wax-varnish mixture, then we add the dry pigment, we stir then the polish is applied using brushes or bronze or stainless steel spatulas. The wax must always be hot, you can also heat the tools with a small torch to smooth and make recoveries. There is specific encaustic material, see end of article.

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Encaustic painting is a multi-step process. First, the binder must be melted or liquefied. Then the liquid paint is applied to a porous surface. The wax applied to the support is heated or fused allowing it to form a good bond. This technique, which is more complex than others due to the heat, makes it possible to create works on all kinds of rigid supports. Care should be taken to make the first keys penetrate the substrates so as to create a good base for future coats, if any. You can also use a heat gun and specific equipment (see next page) to heat the wax as well as all the tools to model the pictorial material.

II) The wax cold

We grind the pigments with water Then we make trochisks (see definition) of these: when they are dry, they are added to a mixture made over low heat and in a bain-marie of waxes and sandarac or dammar varnish. This binder is in the form of a paste, creamy and ductile, with a yellowish-white hue. Depending on the pigments, the proportions of waxes and varnishes are different : Recipe for a lead white Pigment: 30 g Beeswax 25 g Carnauba wax: 5 g Dammar varnish N ° 1: 15 g Recipe for a Yellow ochre Pigment: 30 g Beeswax 30 g Carnauba wax: 10 g Dammar varnish N ° 1: 20 g Recipe for a Blue ultramarine Pigment: 30 g Beeswax 25 g Carnauba wax: 5 g Dammar varnish N ° 1: 15 g Recipe for a black Pigment: 30 g Beeswax 30 g Carnauba wax: 15 g Liquid varnish N ° 2: 25 g


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ENCAUSTIC WAX PAINTING Recipe for a Carmine Red Pigment: 30 g Beeswax 35 g Carnauba wax: 10 g Liquid varnish N ° 2: 15 g Recipe for a Sienna earth Pigment: 30 g Beeswax 30 g Carnauba wax: 10 g Dammar varnish N ° 1: 20 g The work is done with pig bristle brushes, one for each pigment, when the wax has completely hardened, it can be polished with a soft cloth to give it a satin or shiny finish. As a last resort the cooled paint can be polished to reveal the luster of the wax and the resin. The opening of such works is neither necessary nor obligatory. Until the 1930s, artists who practiced encaustic were mostly European. Encaustic was little known in the United States before American artist Jasper Johns popularized the technique. Although critical and historical literature is laconic, encaustic recipes, methods and material have changed dramatically from the origins to the present day. Encaustic uses wax, heat, and generally heat resistant pigments to create a work of art or to varnish a work of art or sculpture. The term is derived from the Greek "enkaustikos" meaning "to burn, to burn in the fire, to burn internally", thus the encaustic is characterized by the use of heat and the sensation of burning which it gives off and, therefore, literally separates the medium from other styles of painting that use wax (like wax emulsions or cera colla) because heat is present in all stages of painting. Art historians find it difficult to categorize this complex medium. Yet artists have found in encaustic a way to visually express a unique poetic beauty. Thus Plutarch writes: "A beautiful woman leaves in the heart of an indifferent man an image as fleeting as a reflection on water, but in the heart of a lover the image is fixed with fire like a encaustic painting, which time will never obliterate ". In 1895, an excavation site in Saint-Médard in France revealed the tools of a female artist, many of which have been associated with wax painting, such as a "cauteria": a burner, as well as containers of waxes and resins. These findings provide evidence that the Greek traditions of encaustic painting spread to Rome and Europe. Pliny's detailed description of encaustic

suggests that this art form was an essential medium in Rome in the 1st century AD. Our era. It is only from the following centuries that we have examples of secular uses of the encaustic technique, they come from Egypt. This geographic shift seems to be a continuation of the Greco-Roman style of previous centuries. Before the immigration of the Hellenistic peoples, the use of wax does not appear to have been used for artistic purposes, but in Egyptian funeral services. All the Egyptian encaustic works that we have today and all those mentioned in ancient writings relate to funerary art. Lucas Cranach the Elder, Andrea Mantegna, and perhaps even Leonardo da Vinci, it seems, experimented with encaustic during the mid-Renaissance. At the start of the 18th century, the Comte de Caylus, a French antiquarian interested in Pliny's writings on encaustic, began to experiment with this medium. Caylus, and artist Joseph-Marie Vien, tested several formulations and applications of the wax medium. Finally comes painted and exhibits his own works in wax. Another intellectual, Denis Diderot, "vilipende Caylus ... and preferably praises the encaustic experiments of Jean-Jacques Bachelier. In 1829, Paillot de Montabert, an artist-painter, publishes a Complete Treatise on Painting in 9 volumes , including one dedicated specifically to encaustic. In 1934, a German artist named Karl Zerbe emigrated to America, where in 1935 he became the head of the painting department of the Boston Museum school and he began to look for ways to explain "what characterizes a picture." His research led him to wax, a medium that would allow him to paint layers of paint while avoiding long waiting times for the oil to dry. He discovers that hot waxing on canvas gives him immense flexibility. His experimentation finally led him to a subtle mixture: 90% beeswax and 10% linseed oil thickened in the sun, heated to 107 ° C, which he uses with an electric paddle and thanks to the air blowing. hot and with hand lamps, it achieves fusion. He demonstrated his approach in a 1957 film which he directed and later shared with his followers. Nowadays in 2016, one of the ways to train in the technique of encaustic, apart from personal experience, is the existence of many communities and forums on the internet created so that current artists who use this technique can share , support and learn from each other. Famous artists, whose work has already been well received by galleries tend to distance themselves from what many consider "amateur artists" and this is what slows down "the flow of reliable information." Artists are learning from the plethora of data online, from the foundation of encaustic art books and from academy classes, in response to the boom in popularity of encaustic. This popularization is a good thing, but it causes a certain distrust of the artistic commu-


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ENCAUSTIC WAX PAINTING nity towards the facility, because certain professionals accomplished in the technique of encaustic do not share their knowledge, which constitutes a brake on the evolution and the interest that some other artists or amateurs may have in this technique. In short, encaustic, which is such a difficult technique (from start to finish, you need special material that cannot be borrowed from other techniques such as oil or watercolor), is also marginalized and very little known; but the situation is changing thanks to the internet. The art of encaustic has evolved over the years and time has passed from antiquity to formal research published throughout the twentieth century. However, the lack of interest in the subject on the part of the scientific community is a pity, as much better documented and detailed articles would be welcome. It is the goal of encaustic artists and authors to increase understanding and knowledge of hot wax painting or any other pictorial technique, as well as to encourage more in-depth technical research of the art. encaustic art around the world [74].

Heating station with brushes and nozzles.

walnut oil

linseed oil

turpentine

Wax call "wax A" that can be used as a replacement for beeswax. It has the same characteristics as Carnauba wax in terms of melting.

Cauteria 2 different stainless steel tips of 13 cm

Encaustic iron

Heating plate 22 x 31 cm

Cauteria and spatulas for painting with hot wax


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ENCAUSTIC HOT WAX PAINTING Use a metal plate of 50 X 40 cm in order to distribute the heat and to be able to put aside unmelted wax in reserve.

These aluminum cans (bought on the internet) for hot wax preparation are the most practical way to make our wax paint palette.

Wax Titanium white and ocher in fusion for painting and wax in reserve. We add the pigments (which we have already ground in water) that we mix with hot wax as and when we need.

If you don't have a dedicated hotplate, use a hotplate and a 5mm thick iron griddle, then turn on the hotplate to melt the wax.


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ENCAUSTIC HOT WAX PAINTING

wax, titanium white and very bright ocher

put aside the wax so that it does not melt

Wax in reserve

Thick layer of flat wax, brushed extensively Pure ocher glaze slightly passed on a thicker layer

The wax dries so fast that the touch must be fast

The technique of pure hot wax encaustic is the most difficult of the 3 wax techniques, it is located halfway between painting and repairing or even sculpture, it takes time to understand it. The more carnauba wax you add, the more resistant your paint will be to ambient heat, thanks to its high melting point, but its execution will also be more laborious. To start, you have to acquire the dedicated basic material and do many tests on wood or coarse canvas, see the supports on page 377 for the most judicious choice of substrates to use.


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PALETTE OF 42 HEAT RESISTANT PIGMENTS FOR ENCAUSTIC By mixing 2 by 2 you can achieve more than 1700 shades with these 42 pigments. It is necessary to use pigments which withstand a certain heat such as natural or synthetic iron oxides, all natural earths and high performance pigments. If you are using other pigments, be sure to ask your supplier that the pigment is heat resistant.

Titanium white XSL

Black from vine

Yellow ochre

Herculaneum red

Burnt Sienna

Zirconium White

Gray spinel

Barythine white

Spinel black

Gray Mels

Gray onyx

Clay Green Earth

Jarosite

Praseodymium yellow

Titanium orange

Nickel titanium yellow

Natural sienna

Bismuth yellow

Mars yellow

red ocher

Bleu ultramarine light

Brown ocher from Elba

Iron oxide yellow 920 Natural Ombre from Cyprus

Volkonskoite

Kaolin

Chromium Oxide Green

Blue Heliogen

Black iron oxide

Blue spinel

Blue ultramarine dark

Blue Indanthren

Blue ZirconPB 71

Cobalt Blue Turquoise

Iron oxide brown

Iron and zinc brown.

Heliogen Green

verone green earth

Manganese violet

Cobalt violet bright

Vesuvianite

Mars violet


ACRYLIC - SYNTHETIC PAINT Acrylic is a two-phase technique, that is, depending on the resin and the diluent chosen, it can be done with water or with solvents. It dries to form a transparent film very elastic.

Acrylic Plextol Paint B500 I) Aqueous phase

In 6 hours, you can make a dozen shades or a complete palette by making 1 liter of paint each time. The constitution of acrylic paint requires special care. You must have all the ingredients necessary for its constitution and not omit any of them, otherwise the paint will be irreparably missed. The preparation of large quantities is also a success factor, as is the mixer which allows to achieve a perfect mixture of paints. The materials and equipment needed to make acrylic paints of excellent quality are as follows: 1. 2. 3. 4. 5. 6. 7. 8.

Primal AC 35 film applied to ceramic then peeled off

Acrylic resins Plextol® B500 K360 D498 and Acronal 500 D on the right

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1 mixer with a capacity of at least 1 liter 1 acrylic binder = Plextol B 500 for example 1 dispersant = Orotan 731 K 1 antifungal = available 1 ethomeen C25 pH corrector [63] 1 Antifoaming Pigments Q.s.p water

Eminent chemists say "that you should not try to make acrylic paints yourself" just as "commercial watercolors are finer than homemade ones", this is completely false, I will answer them that I do. have done a lot in my career and that if you follow a strict method you will get good quality acrylic paints. It is true that it takes rigor to make such paints and especially to always ensure to incorporate a dispersant such as Orotan 731 K, check the pH of the final binder and use pigments with perfect chemical resistance. The grinding of modern pigments which are very fine is quick and easy, especially with organic pigments, it is enough to wet the pigments the day before, then to grind them with water in a mortar so that they mix perfectly and intimately with the binder in the blender. RECIPE FOR 1 LITER OF ACRYLIC PAINT Put in a blender 70 cl of neutral water ph = 7 30 cl of Plextol B 500 + 1 cl of Plextol K360 5 cl of Orotan 731 K or wetting agent PM 10 drops of Antifoaming 5 drops of Ethomeen C 25 if necessary see pH 30 to 100 g of medium density pigment Mix everything with a blender, let stand 30 minutes, then go back to the blender for 5 minutes and pour into an airtight container with little vacuum above the paint. This forms a base paint that can be diluted with water as needed. In order to be able to put these paints in tubes, they must be given body, because acrylic binders are liquid.

Triethanolamine

Carbopol EZ 2


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ACRYLIC - SYNTHETIC PAINT

Add an impasto agent such as Carbopol EZ2 at a rate of 2 to 5% of the total paint volume and then it can be put into tubes, however I recommend that you use small containers. If you want to work longer in order to extend the paint opening time, add 10% Plextol K360 which makes the film more shiny ; 2% Laponite also increases the open time of acrylic paints.

To make gel, impasto mediums or strong and thick paints, we use RECIPES FOR GELS FOR 1 LITER OF BINDER 3% Tylose to weakly thicken 5 g of Carbopol EZ2 which gives structuring gels 10 cl of ASE-60 or ROHAGIT SD15 medium gels 2 to <4% Laponite to make all kinds of gels a few drops of triethanolamine to neutralize the ph of the binder if necessary, check with a pH meter These doses can be adjusted, until the desired effect Leave on for 15 to 60 minutes after incorporating the gelling adjuvants. Laponite is very versatile.

Orotan 731 K Agent Dispersant

Pure Plextol K360 film after 24 hours. The film will become completely transparent when dry.

+

laponite RD powder

10 cl of Binder N ° 1A + 2 g of Laponite gel

Water Ethomeen C 25

=

Antifoaming

Tylose-MH-300

=

+ Laponite gel made in a mixer for 2 minutes (to avoid lumps) with 10 g of powdered laponite and 110 ml of water. In large thicknesses laponite crevasse during the withdrawal of its water, it is necessary to add a plasticizer to it such as plextol K360 or 1% glycerin. I put 10% Laponite, so when drying, it cracks, you have to use 4% maximum to make plastic gels.

Binder N ° 1A = 5 cl of plextol K360 + 15 cl of plextol B500 + Antifoaming. Just add the previously ground pigment with water to form a paint.

Binder N ° 1A + 1 gr of gel Laponite without pigment

My favor goes to Carbopol EZ2 which gives plastic gels like with Laponite.


ACRYLIC - SYNTHETIC PAINT The amount of pigment depends on the coloring and covering power thereof, on its density and also on the purpose of the desired paint layer. As with ink, it is preferable to use pigments that are well dissociated (very fine), such as synthetic dyes, but also "high performance" pigments (modern types of pigments that are very stable from a chemical point of view) . Avoid heavy pigments, as they may settle and / or flocculate quite quickly in the binder. The problem, as always, is storage; sedimentation sets in, and we are forced to add additives that do not serve the paint, but storage. We have to find the right balance. Acrylic paints seemingly dry very quickly, however the water vapor they contain does not evaporate for a full 28 full days, many paints retain the thinner (here water) in their structure for a very long time. Plextol B500 is a very versatile resin, it can also be thickened with toluene to form glues to form cold coatings, where the dry film is activated or softened by spraying it with toluene.

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Acrylic paint with Mowilith 20 in solvent phase

One can also make coatings and touch-ups by making paints with this polyvinyl acetate in 50% solution in a mixture of 70% ethanol and 30% acetone. Its thermoplastic properties are excellent, it produces flexible films with excellent resistance to light and high transparency. The viscosity of Mowilith at 20 ° C is 4 to 8 mPas Glass transition temperature ~ 30 - 40 ° C Softening point ~ 80 - 100 ° C It is soluble in ethanol + 5% water, in acetone as well as in toluene. It is insoluble in the White Spirit. Take care to grind the pigments beforehand with water in a mortar and then after evaporation of the water, the binder can be mixed with the pigment powders in a bottle. Paint with pig bristle or sable brushes. The binder can be diluted with a mixture of ethanol and 10 to 30% diacetone alcohol to adapt the drying time of the paint. Since each pigment has a different binder demand, experience will teach us the right balance to achieve for an optimal blend of binder and pigments. Use Mowilith 30® if you want a low viscosity thick film. Mowolith 50® and 60® for highly viscous thin films.

Be careful because the canvas absorbs all the water of the binder. Add plasticizer <5% Antifoaming or Plextoll K360

Acrylic paint gelled with laponite, note the dullness of the paint.

acrylic paint made with 50 ml of Binder N ° 1A + 2 g of Laponite gel + very little Hansa yellow PY74

Mowilith

Grinding of Hansa yellow PY74 acrylic paint with 20 ml Binder N ° 1A + 2 gr of Laponite gel + 3 drops of orotan Ethanol diacetone alcohol 731 K and 2 gr of Hansa yellow PY74. on the right result of the painting and color chart on raw linen canvas.


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ACRYLIC - SYNTHETIC PAINT PALETTE PIGMENTS WELL DISSOCIATED (FINE) FOR ACRYLIC PAINT

Titanium white XSL

Lithopone

Barythine white

Spinel black

Smoke black

Sepia

Very light ocher

Indian yellow PY150

Hansa yellow py3

Van Dyck Brown NBr 8

Isoindoline yellow

Lacque of madder

Irgazine Red

Cobalt violet bright

Zinc white

Iron oxide brown 640

White Gofun Shirayuki

Iron oxide yellow 920

Hansa yellow 74

Spinel yellow

Irgazin yellow greenish

Irgazine orange PY 110

Blue spinel

Ultramarine bright

Cobalt Blue Turquoise

Isoindole orange

Mexican cochineal

Blue Heliogen

Cobalt Blue

Orange glacis

Hostaperm Pink

Paliotol orange PO 59

Heliogen Green

Bismuth yellow

Cobalt green spinel

Alizarin violet

Emerald green

Natural Indigo

Victoria Green

Blue Indanthren

Synthetic indigo

Chromium Oxide Green


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ALKYD PAINTS The first alkyd resins were developed in 1901 by WJ Smith and patented in 1914 by General Electric (GE), but they were not used until much later around 1926, when the first alkyd paint was marketed by GE under the name "Glyptal". Alkyd resins have good film forming characteristics and are very versatile in formulating stable and resistant coatings. The craze for these resins lies in the fact that we must reduce the use of fossil materials (petroleum) and in order to meet greener environmental standards. From then on, they became binders of great importance in organic coatings, although during this period other important resins also took a large part in the revolution of industrial organic paints, such as, for example, epoxy, polyurethanes, silicones and latexes which are adjuvants of emulsions more than binders in their own right, they make poor binders, reserve them for masking. Natural rubber or latex is dissolved in ammonia and prepolymerized. Latex is very elastic when dry, but the films it constitutes are yellowing, they are not fade resistant and they become tacky when exposed to sunlight, they tend to adhere only to surfaces. latex surfaces or on absorbent materials like linen or cotton cloth that can be soaked with it. Powdering latex surfaces with talc will prevent the films from sticking together.) Etc.

Due to its ease of handling, good balance of properties and economic value, orthophthalic acid is the most important polyacid for alkyds. It is almost exclusively used in its anhydride form. Isophthalic acid or benzene-1,3-dicarboxylic acid is an aromatic dicarboxylic acid of formula C6H4 (COOH) 2, it is used as a replacement for phthalic anhydride, when faster curing, forming a film harder and a heat resistant coating is required. Maleic anhydride is sometimes used in limited amounts in alkyd formulations. The incorporation of this raw material generally improves the resistance of the paint as well as the resistance to water. Chemical Formula C8H6O4 Orthophthalic Acid is a colorless, organic crystalline acid prepared from naphthalene. It is used in the synthesis of dyes, perfumes and other organic compounds. Isophthalic acid is colorless, crystalline, slightly soluble in water, the meta isomer of phthalic acid is mainly used in the manufacture of alkyd resins, plasticizers, etc. ... Most of the monobasic fatty acids used in the preparation of the alkyd resin are derived from vegetable oils such as soybean oil and linseed oil for fast hardening alkyds.

Alkyd resins in solvent phase

A typical alkyd resin is prepared by heating and mixing, for example, linseed or soybean oil, phthalic acid anhydride and glycerol to obtain a fatty acid containing polyesters. Alkyd resin based paints are usually solvent based paints, these common solvents are white spirit (a mixture of saturated aliphatic hydrocarbons and alicyclic hydrocarbons with a content between 15 to 20% (by weight) d C7-C12 aromatic hydrocarbons, or xylene. These solvent-based paints have a number of advantages over water-based paints. For example, easier application properties, wider use and greater durability. Tolerance to curing under adverse conditions (low temperature, high humidity) and a superior level of performance on difficult substrates, such as very rebellious or powdery substrates. As a result, solvent-based coatings will not be fully replaced by waterborne (water-based) coatings in the near future. The other important components of alkyd paints are thinners and extenders which are inert fillers used to expand or increase the volume of paints. They are also used to adjust the consistency of the paint and to obtain pigments with greater coloring strength. The last important category of alkyd paint components includes additives, they have very different functions in the formulation of paints. One of the most important groups of additives are those with catalytic activity, the siccatives, which harden the paint.

phthalic acid powder

Safflower and sunflower oils are also commonly used as raw materials for siccativated alkyd resins. Soybean oil is widely used (photo below left). The color of the oil is pale yellow, and the percentage oil content of soybean seed can reach up to 56%. The oil is reacted with glycerol at a temperature of about 250260 ° C, to convert the mono-ester of its oil, the resulting product is polymerized with phthalic anhydride to produce an alkyd resin. The product of this resin is a very viscous bright brown liquid (photo below right).

Alkyd classification

The nature and the proportion of polyols, polybasic acids and fatty acids in oils determine the properties of alkyd resins.


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ALKYD PAINTS The number of combinations is enormous and the specificity of an alkyd resin must involve several parameters. The classification of alkyds is based on its length in oil and the type of oil used.

The synthesis of alkyd resin uses acids mixed with natural vegetable oils such as linseed or safflower oil. The acids used for the production of the alkyd resin are polyacid acid chosen from the oligomers of vegetable fatty acids, in particular a dimer or a trimer of vegetable fatty acids, succinic acid (C4H604) or adipic acid (C6H10O4). These alkyd resins, made sufficiently fluid by conventional heating to 80 ° C, are dispersed in water to form a water-in-oil (W / O) emulsion. This W / O emulsion will be reversed by adding water to form an oil-in-water (O / W) emulsion. Creating an alkyd emulsion means starting with the aqueous phase and adding it gradually in order to disperse the alkyd. These alkyd resins are dispersed in the aqueous phase as uniformly and as intimately as possible and for this it is necessary to use emulsifiers (oleic acid or potassium oleate) and / or surfactants. In view of all these data on alkyd resins, we can note that we are far from a simple binder as could be an ink or a watercolor, the synthesis of such resins is only possible in the laboratory and performed by chemists familiar with such products.

soybean for alkyd

Alkyd Resin

Depending on the percentage by weight of fatty acid in the resin, alkyd resins are called short oil (<45%), medium oil (46 to 55%), or long oil (> 56%). Long oil alkyds are superior in pigment dispersion and rheological properties. But sometimes the oil length also refers to the percentage of triglycerides, in which the fatty acid content is recalculated into triglycerides. The second approach follows from the first by dividing by 1.045. The type of fatty acid used also governs the properties of alkyd resins. The resins are classified as siccative, semi-siccative and non-siccative, depending on the degree of unsaturation in the fatty acid residues, whose iodine number is respectively> 140, 125 to 140 and <125 knowing that , the higher it is, the more the oil contains unsaturated molecules (the more C = C double bonds there are) so is likely to crosslink in air and thus harden.

Alkyd resins in aqueous phase

There are also water-based alkyd paints, the diluent and solvent of which are water. These are natural vegetable oil emulsions.

What may be regrettable for the artist who suddenly no longer knows what he has in his hands, this time it is the loss of the profession by not knowing the materials he uses, they are so complex. Hopefully, the evolution of materials will allow the artist to make binders that are easier to make on their own. I still want to clarify that these resins were not originally created for easel painting, but to make plastics, coatings for building paints and for industrial paints. It is only recently that they have made their forays into the artistic realm. All the suppliers offer it in the form of paint in tubes, but to my knowledge there is very little reference of pure alkyd binder sold "by the liter". An alkyd paint is considered to be a paint, the binder of which is 50% or more pure alkyd resin. Be sure to read the packaging of the paints you buy. Alkyd resins are binders in their own right, they are very similar to oil paint, while having superior crosslinking speed, alkyd resin paint can cure in 2-3 hours, and recoat in 8 hours hardly this advantage, if any, is not the only one. The alkyd has very good adhesion properties, film-forming, its shine is remarkable, its compatibility with pigments is also one of its great qualities as well as its hardness and its resistance to water for alkyds in the solvent phase. It is now known that alkyd resins turn yellow. In contrast, aqueous phase alkyd resins have a short outdoor life due to poor hydrolytic stability. We are currently not absolutely certain if these binders are stable over time for easel paints, so use them with full knowledge.


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ALKYD PAINTS Grinding pigments with the alkyd binder

It is performed first with water or pigment paste, then 40% oil and 60% alkyd resin are added to the already ready paint mass, we continue to grind the paint only a few minutes in order to not to risk burning the material and also in order to incorporate the alkyd phase well into the rest of the oil paint. The tubing is done immediately, so that the paint does not harden in the meantime.

The steps of the constitution of oil painting

Pigments that can be used with alkyd resins As much as possible, favor high-performance pigments, rare earth pigments, ochres and earths, you will thus obtain quality paints and of course long-lasting, see palette page 359. Because the binder as much as the pigment, in half conditions the final stability of a work of art. avoid as much as possible (if not for glazes) organic pigments in oilseed paints.

Alkyd Resin

Drying oils

Mastic resin from Chios

Litharge

Rubens Medium

Linseed oil or walnut oil

Saponified Carnauba and Bee Waxes Pigments

Comment est faite la peinture à l’huile Illustration ©2021 David Damour

Venetian wax medium


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THE TECHNIQUE OF OIL PAINTING The oil is a collective invention that has been improved throughout its history. Oil painting has been known since antiquity, Pliny and Vitruvius mention the use of layers of oil on walls painted in minium [127]. In the 10th century, a priest named Theophilus Presbyter described oil as a paint binder in a book "Schedula diversum artium" or Treatise on the Various Arts. Jan Van Eyck, a Flemish painter, was a brilliant innovator, from 1410 he perfected and developed cooked oils to which he added siccative, then finally he discovered a transparent liquid, the essence of aspic and turpentine which allowed to dilute the paints and in particular for the aspic to be able to dissolve all the resins. This introduces a whole new concept in painting, that of "transparency of paint layers by overlays and the use of glazes". [Johannes de Ketham a German physician living in Italy at the end of the 15th century was the first to describe the use of turpentine as a solvent for varnish resins]. Antonello da Messina came to Flanders to learn the technique from his colleague, which he brought back to Italy. It should be noted that the development of drying oil allowed the creation of printing ink, it can be said in the broad sense that Van Eyck participated in its invention. A century later, Rubens gave its letters of nobility to the technique of oil painting, a period known as the "golden age of oil painting", in addition to being a virtuoso of painting, he developed a gel medium - [or he improved a gel already known by Maarten Van Heemskerck. ?] - with the help of Théodore de Mayerne (a cold solution 1 to 1.5 of mastic resin in aspic or turpentine essence mixed 1 to 1 with cooked oil siccativated with lead), which allowed to transcend the limits of the technique of oil painting. Rubens (circa 1600) used mastic resin because he was unfamiliar with dammar resin, since it did not arrive in Europe until around 1827. One of the notable qualities of the oil paint once crosslinked is its resistance to water, another of its qualities is the rendering of the three-dimensional space that it allows to render by means of transparent and shiny paint and glazes made with thixotropic gel. The technique of oil painting is governed by rules, of which the most important are: - Sizes and aqueous plasters must dry for 28 full days, this is the time it takes for the steam to completely evaporate from the substrate. - Avoid coatings that are too thin, too porous or poor in skin glue (you can cover them if necessary, with a hand of skin glue or insulating varnish but it is not the same), it is preferable to origin to decatate the fabrics well, to glue well and to coat your supports well in order to avoid this pitfall.

- Give preference to halftone prints such as a mixture of yellow ocher and white (iron and lead). - Before starting to paint, degrease the surface of the support with a decoction of Panama wood and leave to infuse in water for 10 minutes. The substrate therefore acquires an astringent character, so it retains the paint better. - You can rub the surface of the plaster with garlic, you can also sand it with horsetail or triple zero sandpaper with water. Sand with triple 000 sandpaper between each coat, before repainting a new coat, this prevents premature cracking. Use mediums rich in: Resin = Rubens gel medium = shine Saponified wax = Venetian medium = satin / matt Rubens' medium, Venetian medium, fumed silica and Barium white give the paint thixotropic qualities, elastic qualities and flexibility qualities. - It is necessary to paint greasy (gloss) on thin (mat), viscous or unctuous on rough = the support must be absorbent and irregular so that the layers of paint can hang. The more layers you add, the more resin the binder must contain and less oil that will make the film too shiny and brittle. - Avoid juices diluted with pure essence, as the resinfree oil may migrate into the deep layers of the work once the solvent has evaporated and end its migration into the canvas. - Before starting to paint, you can cover with a paper towel or a spalter the entire surface of the support with a mixture of white, pigment rich in iron (yellow ocher) or manganese (intense brown or Manganese Gray) and Rubens medium diluted 3 to 1 which binds the paint and makes it hang intimately on the support, this print acts as a binding agent and mordant. Easel painters from the 14th to 17th centuries often began the first coats of their works with tempera or oil-in-water type emulsions with casein or skin glue. The advantage of such coats of paint is that they dry very quickly, which makes it possible to keep on oiling, very quickly. The other advantage of emulsions is that they allow you to adjust the ductility and thickness of the dough, which can go up to the consistency of butter and which gives a plastic character to paints. Van Eyck used oil paint to paint on a cool "bed", consisting of a mixture of mastic or copal resin, oil, cherry gum and essence (emulsified oily varnish or not), with which he garnished the painting, he finished with glazes with "Venice Balsam" said Bijon at that time. This technique gives colorful and agatized paintings. I have personally tested this method on wood and you get very vivid paintings, like enamelled and glazed. It should be noted that oils cooked over high heat give films of paint more varnished than clear oils.


MEDIUMS FOR OIL PAINTING PAINTING IN SUCCESSIVE LAYERS

Begin painting the rough outline with medium, a mixture of mastic resin and black oil, at a ratio of 3 to 1, and aspic or turpentine as a light thinner. It would be a good idea to start the first coats with a technique other than oil, for example with an aqueous technique such as an oil-in-water emulsion with casein, tempera, cera colla and even l acrylic thus allowing to set up the pictorial space of the work without blocking the support; this creates an ideal underside for oil recovery. To redo the sketch, use a mixture of mastic resin and oil in a ratio of 2 to 1 depending on the number of layers remaining, with a medium containing more resin and less oil. This is done until the last layer, which will consist of pure Rubens medium. The layers of paint will be all the more thin as we get closer to the finality of the work; the more layers are applied, the more the paint pastes must be low in oil and rich in mastic resin. You can finish the work with glazes [127] with pure Rubens gel, this avoids any cloudiness and you have a better overview of the work. Leonardo da Vinci could pass up to 20 layers of glaze or sfumati, 2 µm thick, one for each pigment, the soluble part of some pigments explains and allows such finesse.

THE PAINTING "ALLA PRIMA"

To paint works in a working session, we can use a medium such as the Venetian Medium with saponified wax, it allows to achieve rich impasto as well as thin layers of paint, velatures; this medium is an essential component of flexible oil paints which can follow the movements of the substrate if necessary. The support must be well glued and the coating must be neither too absorbent nor too shiny, taking care if necessary to sand it and then to degrease it before starting to paint, then to let the water that can evaporate. be in the plaster.

MEDIUMS OF OIL PAINTING

Here are the recipes of some modern mediums of the painter's trade.

NATURAL CRYSTAL MEDIUM

Mixture of Rubens gel medium and fumed silica or walnut oil and amorphous fumed silica, a thickening and thixotropic agent or ACEMATT® HK 125. Grind the silica with water, allow to dry then incorporate it with the Rubens medium. Apply in a thin layer. You can use different types of oils, such as carnation, flaxseed or safflower oil, to achieve different viscosities. Depending on the amount of silica used, the consistency of the gel will be firm or ductile.

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SYNTHETIC CRYSTAL GEL MEDIUM

Mixing a solution of Laropal® A 81 in shelsoll A and fumed silica or ACEMATT® HK 125. Grind the silica very finely on one side with water, allow to dry then incorporate it hot or ambient heat with the Laropal. Apply in a thin layer.

SATIN MEDIUM

Dissolve 25% ketone resin (which does not have a binding force, like wax) such as MS2-A resin with 25% Laropal A 81 acrylic resin for 24 h in 30% Shellsol A or D40 then mix with 20% carnation oil. We can add 1% of Tinuvin 292 and 900 to give it anti-UV qualities. It is a transparent, slow-setting medium that gives a satin paint film.

WAX GEL MEDIUM

Mixture of PARALOID B72 in 25% ethyl acetate with natural saponified wax + polyethylene wax which is dry saponified as for the Venetian medium. Mix 100 g of 25% Paraloid B72 in ethyl acetate with 60 g of beeswax + 20 g of polyethylene wax or microcrystalline wax saponified with a little ammonia dissolved in a little water. Incorporate the wax in the Paraloid at room heat or at gentle electric heat then put in a tube. Medium in paste with saponified wax in aqueous phase produced for emulsions of the oil-in-water type Make (as for the saponified cera colla) using 10 cl of ammoniacal water with 60 g of beeswax + 20 g of polyethylene wax. As binding material we use: 80 g of Regalrez 1094 at 20% in Shellsol D40 or in a mixture of: - 25 g of Laropal A 81 dissolved in cold 48 hours in 75 ml of Shellsol A or Shellsol D40. The wax is emulsified with the oil previously emulsified with soy lecithin or egg yolk. A kind of synthetic Venetian medium is obtained that can be easily mixed with oil-ground paint pastes.

CONCLUSION

The oil painting technique allows painting on any support if it has been properly sanded and degreased. you have to respect some basic rules, but essential ones. Oil can paint absolutely everything, unfortunately it is a very lively, unstable, constantly changing technique that we can try to tame; the masters of the past have succeeded in some way; they used to say "start your work with a broom and finish there with a needle", that is to say: sketch quickly and take care of the details only at the end.


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TUBES OF OIL PAINT GROUNDED FOR GRINDING PAINTS SEE PAGES 310 TO 313

Tubes of oil grounded paint 2014-2016©David Damour


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PALETTE PIGMENTS CHOSEN FOR OIL PAINT AND ALKYD

42 PIGMENTS CHOSEN FOR THEIR BEAUTY AND PURITY, THEIR COMPATIBILITIES AND STABILITIES WITH OIL

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