Pressure-sensitive adhesive labels

Status report on LC research efforts to evaluate pressure-sensitive
adhesive labels

To date, the Library of Congress has been using a heat-activated
adhesive label for both call number labels and barcodes.  Because of
the unwieldy nature of the machines required to produce a
heat-activated label and the systems enhancements which permit
downloading by catalogers, the Library is investigating the
feasibility of shifting to a pressure-sensitive label without an
overlay/label protector.  The following describes preliminary
research conducted for a limited purpose: the development of
performance specifications used in the procurement of label stock.
Much more extensive research would be required to arrive at
conclusive results.

The current research project is a joint effort of the Binding Office
and the Research & Testing Office focusing on specifications for
spine labels and externally-applied barcodes.  The label must adhere
to a wide variety of substrates that are used as book covering
materials and the image on the face stock must be permanent.  The
first phase of the research has been completed, with two more phases
to follow.

Phase I involved testing 18 labels on 5 substrates typical of
covering materials found on publishers' bound volumes.  The labels
were tested for wraparound capability (adherence to non-flat
surface); brightness after aging and exposure to light; and adhesion
to the substrate after an initial 72 hours dwell time and after
aging.  Phase II, being conducted currently, will test 6 of the
labels from Phase I for adhesion and brightness after an extended
period of aging; compatibility of face stock for printing with
laser, dot-matrix, and thermal transfer printers; and abrasion and
solubility of the printed image.  The third phase will be to test 16
other label stocks with the full range of tests determined by Phases
I and II.

In addition to this research effort, a field test to label 12,000
volumes is being conducted in July using label stock custom-made by
3M which combines the best face stock and the strongest adhesive
identified in Phase I of the testing.

Debra McKern
Acting Chief, Binding Office
Preservation Directorate
Library of Congress
Washington, DC   20540

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                   Conservation DistList Instance 9:3
                   Distributed: Monday, June 19, 1995
                        Message Id: cdl-9-3-004
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