Effects of repeated freezing on paper strength

Swedish National Testing and Research Institute has made a test on
paper which was frozen and thawed three times over a period of four
months, to find out if the mechanical properties were changed after
the treatment. The test samples were selected from the institute's
reference collection of tested paper. Three of the papers were made
of chemical pulp and three of rag; in all six different kinds, from
the period of 1910 - 21.

The results showed that there were no significant negative effects
on the paper strength, measured as folding endurance, according to
standard: SCAN-P 17:77.

The report will as soon as possible be published in an English
version with the title:  "The effects of repeated freezing on paper
strength" (SP-report 1996:19  ISBN 91-7848-623-8), and can at that
time  be ordered from the institute on E-mail:info [at] sp__se   or
Fax: +46 33 13 55 02

The test was ordered by the "Swedish working group of the Nordic
Committee on Insect Pests in Archives, Libraries and Museums". The
Committee has been working with pest problems in general since 1984,
and after 1988 more intense with a research project, to find out if
it's possible to use pest control methods that has no negative
effects on humans, documents, objects and on the Nature (to avoid
insecticides like DDT). Freezing is one method that correspond to
the criteria's ahead and has the right effects on the pest insects.
But as a method it has to be repeated several times over a period,
to assure that the all the pest insects are dead. The question is
however, can this repeating of freezing and thawing damage the
materials? To get an answer on that some of the research work has so
far been dealing with paper and textile materials.

For further information on the research project and the Committee
work please contact

    Monika Akerlund (co-ordinator)
    The Swedish Museum of Natural History
    Zoo-TAX
    Fax: +46 8 666 41 25
    zt-monika [at] nrm__se

Lars Bjordal
Senior Conservator
Uppsala University Library
Sweden

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                  Conservation DistList Instance 9:78
                   Distributed: Friday, May 24, 1996
                        Message Id: cdl-9-78-001
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