VPD papers

I recently came across four sealed packages of rather yellowed envelopes
(25 per package). Inside each package is a sheet labeled: V.P.D. (Vapour
Phase Deacidification).  The sheet lists the manufacturer, B.G.
Robertson Laboratories (U.K.), and the American distributor, Interleaf,
Inc. (Minneapolis).  There are no instructions for its use.  I have no
idea when this item was purchased; it was here when I was hired in 1991.
I have read the brief discussion about this product in DePew's LIBRARY,
MEDIA AND ARCHIVAL PRESERVATION HANDBOOK (1991), 167-168, which
describes how it is used and states that the distributor's claim that
the product buffers paper against future acid attack is not
substantiated.  My questions are: Is anyone still using and/or
recommending this product?  What is its shelf life?  Is it worth keeping
and using?  Thanks in advance for your help.

Mike Widener
Archivist/Rare Books Librarian
Tarlton Law Library
University of Texas at Austin
727 East 26th St.
Austin, Texas 78705-3224
512-471-7263
Fax: 512-471-0243

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                  Conservation DistList Instance 8:33
                Distributed: Thursday, November 3, 1994
                        Message Id: cdl-8-33-006
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