Slant Washing


This week, Jamye has been cleaning a series of hand-colored etchings using a technique known as slant washing. An alternative to standard immersive washing practices, slant washing is a good option for handling pieces that are somewhat more sensitive.

In this process, the object is placed on a longer sheet of a product called Tek Wipe. One end of the Tek Wipe is placed in a reservoir of clean alkaline water. The object is laid on the Tek Wipe at a slight angle, draining at its bottom into an empty tub. Capillary action pulls the clean water through the Tek Wipe–and the paper object–as it drains. The conservator can help the process along by spraying the object with additional water from the front. As the alkaline water passes through the object, it pulls out acidic impurities, as demonstrated by the pool of darkened yellow liquid that gathers below.

Slant washing has several advantages as a technique. Because the paper piece is not fully immersed in water, it can be washed for a longer period of time without damage. The process is also more environmentally friendly than the standard blotter washing procedure, since Tek Wipe can be washed and reused, while blotter material cannot.

For these particular pieces, the most critical issue was the sensitivity of the media involved. These etchings had a glazing selectively applied to their surface. Glazing is a binder, usually transparent, that saturates the color of an image and gives it gloss. It can be made of materials such as gelatin or gum arabic. In the case of these etchings, the glazing was placed onto the figures of the horses to heighten their visual impact within the scene. Washing these prints in a standard water immersion would likely have dissolved the glazing and possibly damaged the media underneath.

The etchings had darkened over time as the paper became more acidic. Slant washing removed those accumulated acidic byproducts in a carefully controlled manner, and the cleaned pieces can now be flattened and framed for display.