Unbuffered map folders

Does anyone know a source for large (36" x 48") 10 pt. acid-free pH
neutral, unbuffered map folders which would be suitable for the
storage of architectural reproductions such as blue prints, which
may be sensitive to alkaline environments?  All of the suppliers
I've contacted make their map folders out of stock that is buffered
to about pH 8.5.

Karen Potje
Head, Conservation/Preservation
Canadian Centre for Architecture
1920, rue Baile
Montreal, Quebec H3H 2S6
Canada
514-939-7000
Fax: 514-939-7020


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                  Conservation DistList Instance 14:42
                 Distributed: Monday, February 5, 2001
                       Message Id: cdl-14-42-024
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