Removing stain from tracing cloth

I am an intern at The London Metropolitan Archives. I have been
working on several architectural plans damaged by greasy and waxy
stains all across the surface. The supports are made of tracing
cloth, the technique is hand ink drawing and watercoloured. I would
like to know how to remove these stains from the surface, possibly
an un-watery method because the tracing cloth is very sensitive to
the humidity and brushing water could erase the glossy surface,
which is a very typical trait of this support.

Elisa Sgaravato, LMA


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                  Conservation DistList Instance 18:42
                  Distributed: Friday, March 11, 2005
                       Message Id: cdl-18-42-038
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