Distorted cellophane

I am currently evaluating a collection of printed plastic packaging
films, dating from approximately 1940-1970. The materials are a mix
of cellophane, polyethylene, acetate, and possibly polyvinyl
chloride. Many of the items are folded and cannot be safely opened
without creating tears. The cellophane (and/or acetate?) exhibits
some shrinkage with distortion. The conservation literature on
cellophane is mostly concerned with tape removal, but I am looking
for information on preservation and conservation. Primarily I would
like to know if anyone has tips for flattening these plastic films,
mainly the cellophane.

I think passive humidification could work, but I am not certain
which items have a moisture proof coating and how that will
influence relaxation of the support. Has anyone used a chamber to
humidify and flatten cellophane? Was warm moisture introduced? The
primary goal is to unfold the items, not achieve perfect flatness.
Also, if anyone can tell me the ideal storage conditions for
cellophane, that would be appreciated.

Laura Wahl
Library Conservator
Hagley Museum and Library
PO Box 3630
Wilmington, DE 19807
302-658-2400 ext. 236
Fax: 302-658-3267


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                  Conservation DistList Instance 22:30
                Distributed: Tuesday, November 25, 2008
                       Message Id: cdl-22-30-011
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