Copper in starch paste

Silvia Oliveira Sequeira <s.o.sequeira [at] gmail__com> writes

>In the literature we have not found any information about the
>combination of starch paste with copper. We thought maybe it was
>some insecticide or fungicide compound added to this bio-susceptible
>glue, but there is nothing on this subject in the articles we have
>found. Does anyone know anything about this starch paste/copper
>combination?

In The Chemistry and Practice of Sizing by Percy Bean and R.
Scarisbrick, 11th ed., The Bragdon, Lord and Nagle Co., Inc., New
York, 1922, pp. 285,6, the use of copper sulfate added to starch
sizing as an "antiseptic ... as a preventive of mildew..." is
discussed.

   "For pure sizing one half per cent. of sulphate of copper on the
    weight of flour or starch is sufficient to prevent mildew,
    unless cloth be allowed to get wet or very damp."

Jack C. Thompson
Thompson Conservation Lab
7549 N. Fenwick
Portland, Oregon 97217
USA
503-735-3942


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                  Conservation DistList Instance 21:37
                  Distributed: Friday, January 4, 2008
                       Message Id: cdl-21-37-004
                                  ***