Barrier materials used in framing

I am currently researching materials used as a barrier between the
back of a mount and the backboard of a frame (usually oil tempered
hardboard). I am currently looking at the effects of using melinex,
aluminium foil, 'marvelseal' and 'moistop'; if anyone has any
comments on these or any other materials, or on techniques of using
them and sealing up frames, I would be very grateful to hear.

Emily Gilbert
Paper conservator
The National Museum and Galleries of Wales
Cathays Park
Cardiff CF1 3NP
UK

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                  Conservation DistList Instance 13:34
                 Distributed: Sunday, December 12, 1999
                       Message Id: cdl-13-34-014
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