Copper in starch paste

Mark Allen <mark_allen [at] flintshire__gov__uk> writes

>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. ...
>>...
>>... Does anyone know anything about this starch paste/copper
>>combination?
>
>There are references to fungicides added to starch paste in the
>publication The conservation of books and documents by WH Langwell
>1957, There are two substances mentioned that could be the cause of
>the green colour: copper naphthenate or copper oxinate.

I would have to agree with Mark that Langwell is a likely source for
the copper here. Yash Kathpalia in his book on conservation in India
(Conservation and Restoration of Archive Materials, 1973) mentions
the use of thymol to combat mold and the use of phenol and cresol or
acetic acid in paste as preservatives.

Heim, Flieder and Nicot in their paper on combating molds in the
ICOM Conservation of Cultural Properties do not mention copper
products (1968).  In the Baroda Museum Bulletin of 1969 edited by
V.L. Devkar, which was basically a summary of methods used there, no
mention of copper based treatments is made. Paradichlorobenzene, and
Carbon disulphide are noted as fumigants, Chloramine T as a
treatment for mold,but they do also report copper traces in the
paper.

In my notes from preparing works on paper from India and Persia,
especially from the Ehrenfeld Collection in the 1980s, that many
paper hinges and tapes had been applied with a variety of papers and
adhesives.  In some cases when I attempted to remove some of these
using CMC some color transfer occurred into the CMC from the paper
tapes.  One might consider the possibility of contamination from the
papers used for hinging or attachments in addition to or in place of
the paste as the source.

Niccolo Caldararo
Director and Chief Conservator
Conservation Art Service
San Francisco, CA


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                  Conservation DistList Instance 21:39
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