Conservation in Action: Demons and Demon Quellers

Conservation in Action: Demons and Demon Quellers, September 2017

Conservation and Collections Management
Thursday, October 5, 2017

With the painting properly supported by two layers of lining, the next focus is on flattening the painting before improvements can be made on its structure and appearance. A traditional Chinese technique for flattening paintings and mounting materials is to stretch dry them on a board. In this case, the work table is used instead due to the size of the painting.

The painting is first sprayed with water and allowed to expand. Paste is then applied to the reverse only along the perimeter edges, so that the painting, placed face up, adheres to the table. While the painting dries, it also shrinks and flattens.

The painting adapts itself evenly to the tension and becomes completely flat with the pasted edges holding it in place.
The painting adapts itself evenly to the tension and becomes completely flat with the pasted edges holding it in place.

Although the two layers of lining make the painting stable and provide good overall support, the areas with cracks and tears are still thinner and weaker in structure. For reinforcement, conservators prepare paper strips and attach them to the back of these areas with paste. Watch how a conservator water cuts the paper strips in this time lapse video.

Conservator reinforces weaker areas of the painting using paper strips.
Conservator reinforces weaker areas of the painting using paper strips.

Two directions of light are used to aid in the application of the reinforcement strips. Raking light, when the light source is placed to one side of the object at a low angle, emphasizes the surface texture, allowing conservators to see where strips have already been added. Transmitted light, when the light source is from behind the object, highlights losses and any differences in thickness in the layers underneath the examined surface. Below, a light box under the painting provides transmitted light and allows conservators to more easily see through the two lining layers and spot the location of even the tiniest cracks and tears.

Conservators use a light box underneath the painting to help spot and reinforce cracks and tears.
Conservators use a light box underneath the painting to help spot and reinforce cracks and tears.

To assist in remounting later, a narrow silk margin is attached to the perimeter. It acts as an extension of the painting, providing the additional material that can be trimmed when the painting is squared for remounting. The silk is first dyed to match the basic tone of the painting, and then a thin layer of temporary facing paper is added on the surface for ease of handling and cutting. Once in place, the facing paper is removed.

Conservators attach a silk margin along the top edge of the painting with starch paste.
Conservators attach a silk margin along the top edge of the painting with starch paste.

To improve the appearance of the painting, conservators next prepare silk to fill the areas of loss. The silk is aged with ultraviolet light before being dyed in order to approximate the needed color and achieve the specific tone that will match the surrounding image where the fill is to be applied. Similar to the preparation for the silk margin, a temporary facing is added to the silk infill in order to facilitate handling and cutting.

Two samples (the two small rectangular pieces) are placed in an area of loss to compare their tone to the original painting.
Two samples (the two small rectangular pieces) are placed in an area of loss to compare their tone to the original painting. The sample on the left was chosen, as the one on the right is a bit too red in tone.

To ensure the prepared silks are cut to exactly the right size and shape, outlines of the losses are first traced on Mylar, a polyester film.

Conservator traces on Mylar the outline of an area of loss.
Conservator traces on Mylar the outline of an area of loss.

Silk infill is placed over a Mylar tracing, and working on top of a light box to provide transmitted light, conservators cut the silk along the outlines with a scalpel.

Using a scalpel, a conservator cuts a silk infill based on the Mylar tracing.
Using a scalpel, a conservator cuts a silk infill based on the Mylar tracing.

The infill is applied using wheat starch paste to an area of loss.

Conservator applies the silk infill to the area of loss in the boot using wheat starch paste.
Conservator applies the silk infill to the area of loss in the boot using wheat starch paste.

Finally, the white temporary facing paper is removed.

Conservator removes the white temporary facing paper after the silk infill is applied in the boot.
Conservator removes the white temporary facing paper after the silk infill is applied in the boot.
The area of loss around the boot before (at left) and after (at right) the infilling.
The area of loss around the boot before (at left) and after (at right) the infilling.

It will take several weeks for all losses to be properly filled. The infilled areas will then be inpainted as needed to blend the repairs further into their surroundings. In the weeks to come, conservators will prepare mounting silks and backing papers for remounting the painting into a hanging scroll.