Glue sticks

In answer to Meredith's query about glue sticks:  I too had the same
curiosity about them.  I hand printed a book (on an 1820s handpress)
and had to glue in an erratum slip (to my embarrassment).  I didn't
want to use anything that was not archival.  I wrote to the Avery
Company about their glue sticks (which we had in the department) to
ask if their glue was archival.  I asked specifically, "What is the
pH of the adhesive?"  They sent me a letter in which they said only
that they don't give out their glue formula to anyone.  I wrote back
saying that I didn't want their formula; all I wanted was the pH of
the glue.  They wrote back that the glue's pH was 10.  This seemed
awfully high to me, but I have smeared some out on paper and used a
pH testing pen (admittedly not a very scientific test) and it shows
alkalinity.

I consulted with a couple of conservators who told me that it might
not be good to use such an alkaline glue because its color might not
evolve the same way that the color will on the paper it is stuck to.
That is, the spot where the glue is might show in color variation
somewhere down the pike.

Another conservator told me that the glue is safe--not acidic--but
that he prefers the Uhu glue sticks, which, he said, had a better
glue.  [I don't recall the reason it was "better."]

Sid Berger
Head of Special Collections
Univ. of Calif. Riverside
Sidney E. Berger
Head of Special Collections
Rivera Library
University of California
Riverside, CA 92517
909-787-3233
Fax: 909-787-3285

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                  Conservation DistList Instance 10:15
                  Distributed: Friday, August 2, 1996
                       Message Id: cdl-10-15-002
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