Cellulose nitrate and cellulose acetate

I am a German student in photographic conservation and working on
some cellulose nitrate and acetate roll films (1940-50s) that I try
to relax and flatten with different procedures.

I have ideas about working with:

 Acetone vapours (maybe additional glycerol or plasticisers like
 camphor, methylacetate, methylphthalate)

 baths with glycerol-water (additional alcohol, water)

 humidity chambers for relaxation (different times and humidities)

Can any one have experience or ideas about softening, redimensioning
of aged plastics or can offer citations to literature on the
subject?

Katrin Pietsch


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                  Conservation DistList Instance 20:34
                 Distributed: Saturday, January 6, 2007
                       Message Id: cdl-20-34-010
                                  ***