Overhead projector transparencies

I received an artwork from 1996 for conservation, which consists of
overhead projection transparencies, printed black and white. Does
anybody have any experience with this material? I wonder what type
of plastics the transparencies are made of and whether the material
has changed during the course of time. The foils used for this
artwork are totally transparent and do not seem to be coated on
either side. The most important questions are how to clean them from
surface dirt and fingerprints and what storing conditions are
suitable. I would be very grateful about any information or shared
experience about this subject.

Melanie Nief
Conservator
Staudingergasse 14/28
A-1200 Wien


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                  Conservation DistList Instance 21:37
                  Distributed: Friday, January 4, 2008
                       Message Id: cdl-21-37-018
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