Heat-set adhesive

Rebecca Cameron wrote asking about Ademco heat-set adhesive.  I
believe Ademco are still in business, the last address I have for
them is:

    Ademco Ltd,
    Lincoln Road,
    Cressex Estate,
    High Wycombe,
    Buckinghamshire HP12 3QU
    +44 1268 530331

Fortunately their heat set film is more commonly used for mounting
modern photographs and for museum display boards than as a lining
adhesive.

I have always understood that the adhesive was shellac coated both
sides of a thin paper support.  Whenever I have tried to remove it I
have had similar problems to those described.  The main problem
seems to be that shellac cross-links when heated above a certain
temperature.  I have not yet found any solvent for cross-linked
shellac.  There is a useful section about shellac in C.V. Horie's,
Materials for Conservation, published by Butterworths, ISBN
0-408-01531-4.

Nicholas Burnett
Director
Museum Conservation Services Ltd

                                  ***
                  Conservation DistList Instance 13:11
                   Distributed: Friday, July 30, 1999
                       Message Id: cdl-13-11-012
                                  ***