Leather

Additional cleaning methods

Cleaning using a granular eraser

In this method an eraser—Artgum 211, Faber Castell, for example—is finely grated using a household grater. It is best to use a plastic grater, because metal graters may rust or shed small, metal particles which could damage the leather.

You could also use Draft Clean Powder, a granulated eraser which is available from suppliers of conservation materials.

The eraser grains are spread over the leather, then lightly rotated with the palm of the hand or the flat of the fingers until the entire area has been covered. Because skin contains oils, or your hands could be dirty, wear cotton gloves. If the area you are cleaning is very small or particularly fragile, use a small brush to move the granulated eraser over the surface.

Vacuum clean thoroughly after cleaning to make sure that the eraser crumbs are removed. This is particularly important, as conservators are concerned about the long-term effects of eraser residues on the texture, colour, pH and wetability of the surface.

Emulsion cleaner

Dirt which is particularly resistant to cleaning can be removed using an emulsion cleaner. This formulation is based closely on one described in the literature (Fogle, 1985).

To make this cleaner, you need:

• 20ml of non-ionic detergent, for example, Teric N9, Arkopal N090;

• 2g of carboxymethylcellulose—CMC;

• 1 litre of distilled water; and

• 2 litres of X-4 solvent, hexane.

Mix the non-ionic detergent, CMC, and distilled water vigorously for several minutes before leaving the mixture to stand overnight. This gives the CMC time to swell.

Add 15 parts of this solution to 100 parts of X-4 solvent and shake it vigorously until a creamy emulsion is formed.

This cleaning solution keeps indefinitely, but should be shaken before use.

Before using the cleaner, test it on an inconspicuous area of the object—to make sure that there is no significant effect on the surface coatings on the leather or on the leather itself.

Rub the cleaner onto the surface with a clean cloth, rotating the cloth as it becomes soiled. If the object is very small or delicate, apply the cleaner with cotton buds or some similar soft material. This solution easily removes both fats, oils and water-soluble dirt.