Storing photographic materials

In response to the discussion on non-buffered vs. buffered
interleaving tissue for use in photo albums, we did some testing
here at Northwestern.  In accordance to accepted practice we
purchased non-buffered interleaving tissue about 5 years ago to use
in photo albums.  One album in particular had come down to the Lab
for structural repair. The photos I believe are silver gelatin
prints.

The photos were in good condition with some fading.  One of the
reasons we decided to place an interleaving tissue in between each
page was because the photos were mounted both on the recto and verso
sides of the pages and were touching each other when the album was
closed.

Yesterday I went to retrieve the album and pH tested the tissue.
The result was a reading of 3.2-3-5.  We still have the original
roll of tissue and the reading on that came out to 6.0 pH.  I also
took readings of the support pages both from one that didn't have a
tissue facing it and the other that did, both readings came out at
3.7 pH.  My question is what would be recommended at this point:
remove the tissue and replace with buffered tissue or just remove
and leave well enough alone?

We have other photo albums that will be coming to the Lab in the
near future for structural treatment so once again would
interleaving be an appropriate action?

Deborah Howe / Collections Conservator
Northwestern University Library
1935 Sheridan Road
Evanston Il 60208
847-491-7607




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                  Conservation DistList Instance 13:44
               Distributed: Wednesday, February 16, 2000
                       Message Id: cdl-13-44-013
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