Etching plates with bitumen based ground material

I am researching recommendations and options for the long-term
storage of copper and zinc etching plates dating from the 1960's. I
have found information related to the general composition of most
etching process materials, but I am still looking for information
related specifically to the aging characteristics of bitumen based
hard and soft grounds, and in particular the potential degradation
of these materials.

There is a fair amount of working material (grounds, ink, wax,
varnish and other inclusions) on the surfaces of these plates, some
of which have been worked on both sides.

To preserve the readable surface of these matrixes, we are
considering the incorporation of an anoxic system, or other
scavengers into a storage solution with the goal of inhibiting the
oxidation of resinous coatings, and the corrosion of the metals.

Any information about the storage of etching plates and/or aging
printmaking materials would be welcome.

Shannon Jill Bray, Intern
Conservation Lab
Art Gallery of Ontario
317 Dundas Street West,
Toronto, Ontario, Canada


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                  Conservation DistList Instance 25:41
                 Distributed: Wednesday, March 7, 2012
                       Message Id: cdl-25-41-017
                                  ***