Labels for fiche envelopes

Our staff has noticed some fading or deterioration on some fiche
which clearly aligns with the label on the fiche envelope. My
concern  is that since the paper envelope shows no sign of yellowing
or deterioration, perhaps the adhesive has somehow caused a reaction
with the fiche. I have searched high and low, and my colleague has
contacted GPO, and none of us has been able to come up with
recommendations regarding labels on fiche envelopes.

There is documentation recommending acid-free envelopes for fiche,
acid-free ink for stamping fiche envelopes, standards for heat,
humidity, cabinets, removing rubber bands, etc. And there is
documentation recommending acid-free-foil-backed labels for paper
documents. The recommendation to avoid adhesives when housing fiche
makes me wonder whether any adhesive ought to be avoided on fiche
envelopes, or whether the foil-backed ones would be ok.

If anyone can point me to some documentation or has an answer from
direct experience, I would appreciate it. Thanks,

Nancy R. Robertson
Rare Book Librarian
Collection Management Services
Library of Michigan
P.O. Box 30007
717 W. Allegan St.
Lansing, MI 48909
517-373-9464
Fax: 517-373-3615

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                  Conservation DistList Instance 12:80
                  Distributed: Thursday, April 8, 1999
                       Message Id: cdl-12-80-010
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