Removing pressure sensitive tape from paper

Grace White <grace.white<-at->duke<.>edu> writes

>I am in the process of treating a chromolithograph map from 1890 on
>thin, brittle paper that is almost like newsprint.  It has extensive
>transparent pressure-sensitive tape on the front and back.  ...
....
>For solvents, I have tested water, ethanol, acetone and toluene.
>Acetone applied directly with a cotton swab moderately softens the
>adhesive to allow insertion of a knife beneath the carrier, ...

Have you tried ethyl acetate?  Your comment about acetone makes me
wonder if ethyl acetate might be a better fit.  And don't forget to
try mixtures of solvents, they can be quite effective.  There were
two popular formulas at an institution where I worked previously:

    Formula 1 (more modern tape)
    50% acetone
    30% toluene
    20% xylene

    Formula 2 (older tape)
    30% ethanol
    30% n-heptane
    40% acetone

Do you have a suction table or platen?  Once you find the right
solvent, dropping it through the map so that the adhesive residue
transfers to a facing piece of chromatography paper might be more
gentle than a crepe eraser.

The Conservation Wiki <URL:http://www.conservation-wiki.com>
(chapter 15 of the Paper Conservation Catalog) on the AIC website,
has a good section on tape removal, you might find it helpful to
review.

Eliza Gilligan
Book Conservator, UVa Library


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                  Conservation DistList Instance 27:26
                 Distributed: Monday, December 16, 2013
                       Message Id: cdl-27-26-006
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