Lok Hang WAN e-portfolio 2024

January - March 2024

Internship, CHIMEI Museum, Taiwan

Internship in the CHIMEI Museum

1 Introduction

CHIMEI Museum is a famous private museum in Tainan city, Taiwan. With the focus on western paintings and objects, I have joined their conservation team and participated in daily work including painting treatments, exhibition condition check and conservation related documentations.

2 Conservation Project: Portrait of Archduke Albert of Austria

Type: Oil on canvas

Size: 127.4 x 194 cm (HxW)

Dated: 1630

Artist: (attr. to ) workshops of Peter Rubens

Main treatments: surface cleaning, varnish removal, old patches and filling removal, surface flattening, re-filling and retouching

This is the main project in the internship. The 17th century protrait had a yellowed varnish and two old patches were dented due to the extensive amount of aged animal glue.

The goal for the project is to remove the old varnish and old patches so the protrait will be perfect for exhibition.

Fig 2. (Top) Portrait of Archduke Albert of Austria, before treatment

Fig 1. (Right) Example of aged patch and filling that becoming dent.

Fig 3. After surface cleaning, the toppest former retouching has been taken off easily. However, the filling required extra force to remove.

3 Revealing the original canvas from the over-sized patch

4. Another layer of filling and retouching had revealed. The patch had became more dent over time and previous conservation decided to cover it with a larger area of filling.

Fig 6. (Right) XRF of Pb element for the patched area. It is to check if any underlayer is presented.

5. The revealed tear is in fact tiny compared to the toppest layer of retouching.

Fig 7. (Left) The area comparison of the the former retouching (white) and new retouching (black).

Fig

Fig

4 Frame Water Gilding

Fig 9. (Left)

Sanding the CaCO3 filling.

The treatment of the main project required time to set, meanwhile I have done the water gilding of a frame.

Fig 8. (Left) A painting frame with loss compo, before treatment.

Fig 10. (Right)

Burnishing the gilding using an agate burnisher

5 Conclusion

The main project is a precious experience for me as this is the first time I have done a former patching that has covered a large area of original painting. One of the old patch has revealed been filled twice prevopisly. If I chose to cover the dent with a larger filling like the former conservation, the area would enter a vicious cycle of becoming more dent in the future. As there are a large area of original painting has been covered, I decided to do a surface flattening and remove all the old filling and retouching.

To conclude, the painting is more similar to the artist's original intention after the conservation.

Fig 11 & 12. The patched area before (left) and after treatment (right). The old retouching did not match the revealed original area, and therefore there is a slight difference in the pattern of the armour.

May 2022 - September 2023

Dissertation Project, Northumbria Univeristy

Effects of traditional water swabs cleaning on modern oil paint with commercial alkyd medium products

Fig 1 & 2 (above) Samples were prepared by mixing alkyd products with ultramarine tube oil paint in various ratios.

A1 Abstract

lkyd is a fast-drying medium that has become a popular alternative to slow-drying oils since its invention in 20th century. This project aimed to investigate the impacts of artists’ alkyd media to commercially available oil paint in terms of water sensitivity.

The results found that artists’ alkyd media in ultramarine oil paint can reduce change in gloss but increase change in colour upon water swab cleaning. There is an increase in intensity of hydrophilic -C=O groups in oil paint samples upon cleaning, and 3 out of 4 tested alkyd media can reduce this change in hydrophilic contents. SEM showed the change in surface topography upon cleaning can be reduced by the alkyd medium.

3 (Above) Sample is light aged in a light aging chamber for total light dose equivalent to 50 museum years in standard environment.

Fig 4 (Left) The sample have been tested the water sensitivity with water swab rolling for 50 times after light aging.

Fig

2 Methodology

Fig 5 Glossmetry to measure gloss differences upon water cleaning.

Fig 6 Colorimetry to measure colour differences upon water cleaning.

Fig 7 & 8 Stereomicroscopy to detect any defects by water swab cleaning method in high magnefications.

Fig 9 & 10 Back scattered electron detecting scanning Electron Microscopy (BSE-SEM) compare the changes in surface topography upon water cleaning.

Fig 11 Attenuated Total Reflectance Fouriertransform Infrared (ATR-FTIR) Spectroscopy provide insights to the reason of the change in appearance from molecular content.

3 Conclusion

The addition of alkyd medium had a mixed effects on the paint surface. On one hand, alkyd medium in oil paint could reduce the loss in surface conductivity and changes in surface topography upon ageing. On the other hand, alkyd content concurrently reduced the gloss changes and increased the colour changes upon surface cleaning.

Some insights on the reasons for these changes have been provided through (BSE) SEM and ATR-FTIR spectrometry. However, the reason for alkyd medium increasing the colour changes upon water cleaning is left unknown. Further research on elemental analysis, such as SEM-EDX, and structural analysis, such as mass spectrometry, are suggested for providing full comprehension.

Fig 12 Result presentation in the 41 th Gerry Hwdley Student Symposium, Cambridge University

4 Limitations

1. Less controllable water swabs cleaning effect

2. Short Curation Time for paint film

Fig 13 - 15. (Bottom) Unpredicted conditions appeared in some of the samples which may affect the reading of colourimetry and glossimetry

June – September 2022

Placement, Conservation Office, Hong Kong Government

Internship in Conservation Office, Hong Kong Government

1 Introduction

The summer placement provides an opportunity to participate in various preventive conservation and practical conservation work, including condition checks before exhibitions, pest management, recto dust removal, inpainting and work with analytical instruments such as MA-XRF, HSI and Raman spectroscopy.

2 Routine Management

Fig 1. (Right) Routine pest management in the collection storerooms. Pest sticky pads with dates are placed in every corner of the rooms. If any pests are trapped, identify the type of insect and jot down the data for future preventive measurements.

Fig 2. (Left) Condition checking for loan items with the loan museum representative. Indicate any conditions that are not marked in the original report.

3 Surface Cleaning - Hydrogel

Hydrogel is a hydrophilic, three-dimensional network of entangled and/or cross-linked polymeric material containing more than 90% water. Compared to solution cleaning, the moisture delivery speed can have better control.

3

Fig 4 (Right) Hydrogels are made by cooking the ingredients with constant heat monitoring and stirring on a hot plate.

After all the ingredients dissolved and gave a clear solution, the mixture was poured onto a flat metal plate for curing.

‘The field’ is a modern oil painting without varnish and is water sensitive. Mould spots were found across the whole painting. As aqueous solutions are not available for this painting, the conservation team decided to use hydrogel instead.

Several gel formulas have been tested:

• Agar

• Gelatine

• Konjac/Xanthan (various ratio)

• Konjac/Xanthan with EDTA and NaCl

• Nanorestore gel peggy 6

• Nanorestore Gel Peggy 6 with EDTA

After testing, Nanorestore Gel Peggy 6 is chosen for the mould stain removal treatment.

Fig

'The Field', WU Guanzhong, before mould stain removal treatment

Fig 5-7 Mould stains, before treatment (left), during treatment (middle), and after treatment (right).

4 X-Ray Fluorescence

XRF is an analytical technique that uses the interaction of X-rays with a material to determine its elemental composition.1 When X-rays irradiate a substance, some specific wavelength of X-ray would absorbed by the substance according to the element on the surface and rerelease the energy again with specific wavelength photons. By gathering the data and compared to the existing absorption spectrum, the element composition of the substance can be known.

10. The same region with a highlighting element of gold, XRF. A filling paper with a higher gold concentration is revealed.

5 Reflectance Transformation Imaging

Fig 11. RTI is technical photography that can record any distortions or irregularities on the recto and support, dramatically indicating how the paint was applied with emphasised inherent physical qualities.

It is an enhanced raking light photography by combing 36 photos with different angles of light sources thus a virtual modifiable light source is generated. RTI allows conservators to look at the object from different angles of light source by moving the virtual light in the computer programme.

Fig 8. The XRF image of element of gold on a paper made with mixing fibre and gold dust.

Fig 9. A part of a paper fan, reflective light. There is some loss on the edge and a filling paper is barely seen.

Fig

6 Strip Lining

Fig 12 Strip lining with a heat iron spatula, holding with a wood block. The heated part is then clamped with wood clamps and set for half day.

The strip lined canvas is afterwards reattached to the strainer with the aid of air nail gun. Both lining and original canvas were stapled together.

Fig 13 Stapling the canvas, with one person holding a staple gun, one person holding the canvas on strainer in the right position, and one person check the position of the image on the recto is in the center.

5 Reflection

The placement provides a lot of different experiences in the conservation career including scitific research, practical treatment and routine meseum object managements. Although all the works I have done is just a very basic touch on the topic, these gave me a knowledge on the general work flow in a government museum.

'The field' was removed from the strainger before the surface cleaning procedure. Strip lining were attached to all four edges to strengthen it. A type of polyester fabric is used. The edge of the fabric is feathered for 1cm and attached to the edge with BEVA film.

The attachment of BEVA film to the original canvas is weak and needed to reattach for serveral times until a satifactory strength is achieved.

The differences in a Hong Kong museum and a Britain museum also inspired me in terms of different approach methods. The pratice in conservation varies hugely in different countries and should bare in mind that there is not only one approach to do a treatment.

June 2022

Placement, The Laing Gallery, Newcastle upon Tyne

Conservation placement in the Laing Gallery

A1 Introduction

two-week placement in the Laing Gallery, Newcastle upon Tyne.

The main responsibility is to restore a 19th-century oil copy of The Family of Darius before Alexander the Great

Besides, I helped in the final condition check of an exhibition.

Table 1. Summarized Identification Card

Title (Copy of) The Family of Darius before Alexander the Great Date

Emu. No. TWCMS: F6127

Studio No. 759

Measurements (cm)

Frame: 65 x 110.5 x 5.5 (HxWxD)

Painting: 46 x91.5 (HxW)

Signature unsigned

1837

Artist A Paul Veronese/ by George Frederick Watts

Medium/Support Oil on Canvas / Stretcher

Owner Shipley Museum Inscription “TheFamilyofDariusal“thefeel-ofalexander “aPaulVeronese”. ByGeorgeFrederickWatts Duringhis3yearsstay ToItalyaftershootinghis firstpictureatTheacademy 1837.

Student Lok Hang Wan Keziah Lim

Conservator Ana Flynn-Young

Fig 1. ' The Family of Darius before Alexander the Great', front, before treatment under visible light

2. Verso Cleaning

• dry brush & vacuum

• chemical sponge

• feather clean area under strecher bar

2 Painting Treatment

1. Frame Removal

4. Varnish removal

• solvent test

• decision: propan-2-ol

• use gel & scapel to remove previous oil-based retouching (see next page)

3. Recto Dust Removal

• aqueous solution test

• decision: de-ionised water

5. Retouching

• Apply 10% B72/Xylene as isolating layer

• retouch with resin colour

Remove previous oil-based retouching

During varnish removal, a part of colour on a woman's face cannot be removed by solvent. It may be an old retouching using oil paint.

Fig 2. (left) Old retouching on a woman face, after solvent cleaning. The paint is not soluble in any solvent available in the studio.

Fig 3 & 4. (above) The old retouching stain was removed by gel soaked with acetone to soften the paint, followed by removing mechanically with a scalpel. Carefully not to remove the original paint underneath.

Fig. 5. (left) The painting after removal of the old stain.

3 Frame Treatment

1. Frame Dirt Cleaning

• Majority: cleaned with NH4OH pH 9

• Sizing stain: cleaned with saliva

• Frame compo: cleaned with TAC 2%

Fig 6. (above) The outer frame, halfly cleaned on the right.

2. Replace Lost Compos

Frame compo filling

• Frame removal

• Dirt removal

• Replace Lost Mouldings

• Guiding of Filings

Fig 7-8. (left) Creating compo filling with plastic powder, using a mould moulding from the remaining original fragment of compo.

Fig. 9-10 (bottom and bottom left) Measure the filling compo on a loss part of the frame and cut and sand it to fit size

3. Colouring the Compo

4. Gold Oil Guilding

5. New Compo Toning*

*Placement has not enough time to get to this stage

Fig 11-13 Colouring the compo filling with acrylic paint, then adding oil guilding size, let it set for 30 minutes then apply the gold leaf.

Extra support for add-on glazing

The painting is going to loan to other museum. An add-on glazing between the inner and outer frame would be an easily achievable method for protection.

4 Exhibition Condition Check

Fig 14 (above) Checking the condition of a borrowed painting with light and mark it on the condition report.

Fig 15 (right) The condition reports of the objects are temporary placed on the floor for counting.

5 Reflection

This is the first time I learn how to oil guild a frame. Although as an easel Painting conservation student the major responsibility is to restore a painting, knowing more about painting frames helped me to consolidate my knowledge and widen my skills.

Besides, participated in a museum exhibition condition check let me know

Before exhibition, all exhibited items needed to check for its condition, especially for the loam item. Some loan items are first seen by our museum's conservator and therefore the condition should be checked very carefully.

more about the job of a conservator during the preparation of an exhibition. The condition check only begins one week before the exhibition started, which means all procedure were packed in a short period of time. It is important for us to do the condition check precisely.

21st – 25th March 2022

Placement, Fine Art Restoration Company, Carlisle

Conservation of an altarpiece from 19th century

1 Introduction

Aone-week placement worked on an altarpiece from a set of two in the St Michael’s Abbey church, Farnborough, UK. Worked in a group of four students and guided by two studio's painting conservators.

Table 1. Summarized Identification Card

Title The Visitation (a copy of Sir Peter Paul Rubens)

Acc. no N/A

Date Late 19th century

Artist Unknown

Owner St Michael’s Abbey Church Primary/ Auxiliary Support Canvas / Stretcher

Measurements ~4ft x 14ft

Canvas stamp N/A

Signature unsigned Media Oil on Canvas

Fig 1. 'The Visitation', front, before treatment under visible light

2 Verso Cleaning

1. The area under the stretcher bar was cleaned with feather and palette knife

2. The rest of the verso was cleaned with a dry brush and vacuum

3. The verso was cleaned further with chemical sponges

Fig 2. 'The Visitation', back, before treatment under visible light

Fig 4 (below). 'The Visitation', back, after verso cleaning under visible light

Fig 3. Cleaning verso with brush and vacuum

3 Unframing

1. Remove the rust nails until each side had two left

2. The painting was held by two people, and carefully remove the remaining nails

3. The painting was removed from the frame and transported to a safe place with cushions

Fig 5. Cleaning verso under streching bar with a feather

Fig 6. Verso being half-cleaned (top half)

Fig 7. removing nails with pliers

Fig 8. Separated frame (upper) and painting (bottom)

4 Surface Dirt Cleaning

• Solvent test

The surface was tested by 4 types of solvents, the numbers of swabs to clean until no more dirt was removed were jotted down. The swabs were rolled but not rubbed on the surface.

i. DI-water: 2 swabs

ii. NH3OH pH9: 3 swabs

iii. TAC 2%: 5 swabs

Although TAC 2% gave the cleanest result, the varnish layer turned cloudy after dried for a day. Therefore, a safer solvent, ammonium hydroxide in pH 9 was chosen.

Fig 12

After surface dirt removal (upper part), compared to the uncleaned bottom part

Fig 9. Solvent test, from above to below: DI water, NH3OH pH9, TAC 2%

Fig 10. Cleaning the recto with NH3OH pH9 solution

Fig 11 (above). Gently cleaned the recto with large cotton swabs

(left).

5 Varnish removal

Fig 13. Solvent test for varnish removal, from above to below, propanol, MEK, acetone and IMS

• Solvent test

Various solvents were used in different areas because they have different sensitivity, and they were tested beforehand.

i. Propanol 50% in white spirit

ii. Propanol

iii. MEK

iv. Acetone

v. IMS (from weak to strong solvents)

Fig 14. Using UV light to check if the varnish removal is completed, surface without varnish does not fluorescence

Fig 16 (above). Wearing a face mask to prevent inhaling voliatile organic solvent when cleaning recto

Fig 17 (left). 'The Visitation', front (partial), with varnish removal on the sky region

Fig 15. Cleaning the sky region with MEK

6 Frame Cleaning

• Vacuum + brush

The frame was first cleaned by dry brush with vacuum to remove loose surface dirt.

• Solvent test

i. TAC 1%

ii. TAC 2%

iii. TAC 4% (from weak to strong)

TAC 2% was chosen to clean the frame.

T21. Frame, after cleaning (left) and before cleaning (right). Thicky dust layer had been removed and the under gold shiny gilding was revealed

7 Discussion

he placement provided a precious experience in handling large paintings, and some concerns may only appear in the large size painting. For example, the canvas is a collage of three smaller pieces of canvas with different weaving. The sensitivity of the paints and the surface appearances hugely varies between areas. Therefore, solvent tests were done in each distinct colour part.

Some parts are quite sensitive to our mildest varnish removal solvent, propanol. Therefore, propanol was used in a diluted concentration, followed by checking on the surface with UV light after every swab. The cleaning process stopped immediately when there is no UV fluorescence was emitted.

Fig 18. Cleaning frame with brush and vacuum

Fig 19. Start the cleaning from a plain surface

Fig 20. Cleaning frame with cotton swabs of TAC solution

Fig