Serigraph on metal foil

I have a puzzling problem with a 1964 serigraph by Lowell Nesbitt.
It is printed directly on a large sheet (approximately 24"x18") of
gold tone foil (foil on mylar?) that is still attached to its
original backing. The backing is paper that is coated to allow the
foil to be easily removed, while the reverse of the foil is coated
with a pressure sensitive adhesive so that it can be applied to
another support. The artist printed directly onto the foil and never
removed it from its original, and probably, temporary backing.

The problem is that an air bubble has formed, running vertically
through the center of the work. I think it is possible that the air
bubble formed because of the shrinkage of the backing combined with
a degradation of the adhesive or the coating on the support but I am
not sure. Has anyone dealt with anything like this or know anyone
who has? I would be grateful for any help or suggestions.

Note: this work has not been exhibited for over a decade, when it
was removed from storage (it was stored flat in a solander box) a
small air bubble was observed in the center of the work. I removed
the window mat last Wednesday (6 Jan 1999) as it was considered
unsightly by the curator and moved the work to the conservation lab
for rehinging. When the chief preparator and I looked at the work
Tuesday (12 Jan 1999) morning (before rehinging) we discovered the
air bubble.) Again any ideas are welcome.

Aimee Leonhard
Assistant Conservator
Museum of Art and Archaeology
Pickard Hall
Columbia, Missouri 65211
USA

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                  Conservation DistList Instance 12:58
                 Distributed: Friday, January 15, 1999
                       Message Id: cdl-12-58-012
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