Exploration of the Practical Application of CO2 Laser Engraving Technology to Sustainable, Non-toxic Printmaking Sterling M. Anderson University of Missouri – College of Human Environmental Sciences – Department of Architectural Studies
Abstract Conventionally, the art of intaglio printmaking (engraving images into copper) utilizes hazardous materials such as acids and solvents and/ or tedious physical handwork. These techniques and materials have an adverse eﬀect on the artist’s health as well as the environment. Therefore, there is a need for healthier, sustainable alternatives to the traditional methods of printmaking. The nature of CO2 laser engraving technology with alternative plate materials lends itself to being a viable alternative to traditional printmaking. The goal of this research was to develop a healthy sustainable printmaking process which produced comparable images to those of traditional methods. Research of material data was conducted to determine plate materials which were more sustainable than copper. Glass and salvaged ceramic tile were selected based on the embodied energy of materials which could be engraved by the laser. A hand drawn image was converted into a digital format and engraved into the plates by the laser. Both raster and vector files were engraved to test the line qualities of diﬀerent file formats and how they compare to the original drawing. After an edition of prints was pulled from each plate, a survey was distributed to a group of students and faculty in the fine arts department to gather data on the quality of the prints in comparison to the original drawing and a traditional etching. In the future, the application of the techniques developed and explored in this research could be used to eliminate occupational hazards of traditional printmaking while still creating beautiful works of art.
Introduction The conventional methods of printmaking use a variety of chemicals and materials that are health hazards. Many of these materials are flammable, and are hazardous to the environment if disposed improperly. Below is a list of materials used in printmaking, their use, and their disadvantages.
Materials + Methods Copper takes a relatively large amount of energy to harvest and refine to a point where it can be used as a plate material. A material which requires less energy to produce would prove to be more beneficiary to the environment. The sum of this energy expended during the lifetime of a material is known as the embodied energy (EE). In order to determine which plate materials would be used in this research, a comparison was drawn between the EE of Copper and the EE of materials the laser could engrave. Embodied Energy (EE) of Laser Compatible Materials Compared to the EE of Copper †
LaserȱCompatibleȱMaterials Leather Stone* Acrylic Fabricȱ(Cotton) Wood** WoodȱInlays/ȱVeneers Rubber Paper Ceramic MetalȱMarkingȱ Glassȱ Plasticsȱ(General)
NoȱData 1.5ȱȬȱ11 NoȱData 143 7.4ȱȬȱ16 9.5 91 70.5 12 *** 15 80.5
Based on these criteria, salvaged granite, salvaged ceramic tile, and glass were chosen as plate materials for this research. Although wood has a low EE, it produces fumes when it is burned and would be too diﬃcult to wipe clean. Granite was later discarded as a viable plate material because of the extreme diﬃculty in cutting it to size without the proper equipment. A hand drawn image was scanned into a digital format and then engraved into the glass and ceramic plates with the CO2 laser located in the Boone County Lumber Building Technology Lab. Both a rasterized image (FigI) and a vector image (FigII) were engraved into separate plates to provide more variance in comparison of the prints to the original image. A copper plate was etched in the likeness of the original image to serve as a control for comparison of the newer engraving techniques. After the plates were engraved, an edition of prints was pulled from each plate. The best prints from each edition were selected to be judged in comparison to the original image. A survey designed to compare the diﬀerent qualities of the plates was distributed to printmaking students and faculty in the Department of Art. Those surveyed were asked to examine the prints and rate them on a scale of 1 to 10 in comparison to the original image based on the following criteria: Line Quality, Line Weight, Tonal Quality, Truth to Original, Artistic Message.
Sixteen students enrolled in printmaking classes in the Art Department responded to the survey. Nine of the students were intermediate or advanced students and seven were beginning printmaking students. The scores from each criterion were added together and are represented out of the maximum total score possible for each criterion. Three students chose not to rate the prints based on their “Artistic Message.” In General: • The raster image engraved in glass ranked towards the bottom in most criteria • The vector images were closely ranked towards the top in most criteria • The copper engraving ranked relatively high in “Line Quality” and “Truth to the Original” but relatively low in all other criteria
Conclusions Based on the Results from the survey, one can draw the following conclusions: • Conventional methods of copper engraving still produce qualities which are held in high regard when compared to laser engravings • Vector engraved images are more desirable than raster images regardless of what plate material is engraved • Vector engraved images can produce qualities which are desirable to printmakers These results are not entirely conclusive. More data would need to be collected in order to determine whether these new printmaking techniques are truly a viable alternative to conventional printmaking. Ideally, data would be collected from printmakers with a variety of experience and from multiple printmaking programs to represent a broader, more general population.
Copper Plates – The matrix in which images are engraved. Disadvantages: • Metal plates oxidize the inks, causing discoloration Hard Ground – Waxy substance used to coat the plate before etching. Lines are drawn into this coating, exposing the metal underneath. Once the drawing is complete, the plate is etched in an acid bath. Disadvantages: • Contains Asphaltum (the same substance used in paving roads) and Naptha which can contain known carcinogens • Requires solvents to break down and clean Acids – Corrosive liquid used to etch lines into the plate. The ground rejects acid, only allowing exposed metal surfaces to be etched. The acid etches lines deep into the plate, creating grooves which will hold the ink. Disadvantages: • In concentrated forms, skin and eye irritant • Mixing the acid creates fumes that are lung irritants and can cause emphysema • Acid strength changes over time, producing inconsistent results Solvents – Used to break down oils and grounds and to clean plates and tools. Disadvantages: • Defatting in skin resulting in dermatitis • Inhalation of solvent fumes causes nausea, dizziness, fatigue • Can be fatal if ingested Inks – Pigments suspended in oil which are transferred from the plate to paper. The entire surface of the plate is covered in ink and then wiped down. The only ink which remains after wiping is contained in the etched lines. The ink contained in the lines is transferred to paper through the application of pressure, leaving the engraved image on the paper. Disadvantages: • Oils imbedded in the inks can cause liver damage when absorbed through the skin
MJȱ/ȱkgȱ=ȱmegajouleȱperȱkilogram;ȱbasedȱonȱtheȱUniversityȱofȱBathȇsȱInventoryȱofȱCarbonȱ&ȱEnergy *ȱLimestoneȱ=ȱ1.5,ȱMarbleȱ=ȱ2,ȱGraniteȱ=ȱ11 **ȱSoftwoodsȱ=ȱ7.4,ȱHardwoodsȱ=ȱ10.4,ȱMDFȱ=ȱ11,ȱPlywoodȱ=ȱ15,ȱHardboardȱ=16 ***ȱTheȱVersaLASERȱisȱincapableȱofȱengravingȱmetals
Other important factors in choosing a plate material included: • Compressive strength – The plates would need to resist the pressure of the printing press. • Chemical inertness – Chemically inert materials would not produce fumes while the laser burned the image into its surface. These materials would not discolor the inks used in printing. • Nonabsorbent and wipeable – The plates would need to be easily wiped clean after inking in order to clearly transfer the image to paper.
Fig I – Rasterized Image Engraved A rasterized image is an image constructed from a grid of pixels.
Fig II – Vector Image Engraved A vector image is an image constructed of strokes and fills following a scalable structure of control points.
Results 122 98
160 140 120 100 80 60 40 20 0
Truth to Original 160 140 120 100 80 60 40 20 0
Line Quality 160 140 120 100 80 60 40 20 0
160 140 120 100 80 60 40 20 0
This research implies most of the occupational hazards and wastes associated with traditional printmaking can be eliminated through the use of laser engraving technology. In order to accomplish this fully, a method of mark making which replicates the fineness and elegance of the etching needle needs to be identified and applied to the laser engraving process. If prints can be produced that match the same quality and character as traditional copper plate etchings, the necessity of older, hazardous methods will be diminished. In further studies, more data needs to be gathered to determine the energy consumption of the laser itself and the EE of the chemicals used in traditional printmaking in order to make a complete energy analysis between the two methods. It would be beneficial to explore the use of acrylic and water soluble inks as sustainable alternatives to the oil based inks used in this study. The exactness of the laser and its cutting function open possibilities for exploring registration techniques as well as alternative plate cutting techniques. The possibilities for future application of laser engraving to printmaking are very promising and can only be limited by human creativity.
130 115 92
70 50 30 10
A = Copper Engraving B = Raster Image in Glass C = Vector Image in Ceramic D = Vector Image in Glass
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Bobbi Hauptmann – Mentor Dr. Ronald Phillips – Faculty Advisor Christopher Daniggelis – Printmaking Instructor Eric Sweet – Printmaking Instructor