Removing varnish from map

A colleague who is not on the Internet would be most grateful if she
could have any information on removing varnish from a fairly large
map. It is a printed map on thick paper, with a dark brown coating;
she has tested the coating, and it seems to be soluble in IMS. Some
years ago, I helped remove varnish from several large maps, but we
always found a problem with the dissolved varnish being absorbed
into the paper, and leaving it a light but permanent brown. How can
one get around this problem, and what other problems can she expect?
She would also be interested to know about the hydroxypropyl
cellulose ethers Klucel E and Klucel G. I have sent her the AIC
Catalogue page referring to them. Does anyone out there know more
about specialized applications? Are there any caveats to their use?

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                  Conservation DistList Instance 10:78
                  Distributed: Thursday, March 6, 1997
                       Message Id: cdl-10-78-010
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