Oddy tests of unbleached cotton calico

Linda S. Roundhill <artsconservation<-at->comcast<.>net> writes

Valerie Tomlinson <vtomlinson<-at->aucklandmuseum<.>com> writes

>>I have recently done a series of Oddy tests on a variety of proposed
>>display materials.  While at it, we decided to test the unbleached
>>cotton sheeting we use for storage covers and mounts.  Of all the
>>tested fabrics, this one came out with the worst results, with some
>>white fuzziness on the lead coupon, and a slightly darker colour to
>>the copper coupon.  ...
>
>I assume this unbleached cotton was washed thoroughly and dried
>first to remove any chemicals?  ...

Because cotton is not a food crop, limitless amounts of pesticides
are applied in the farming of it, including systemic pesticides
which essentially become part of the plant as it grows and therefore
can't be removed by washing.  It would be interesting to repeat the
tests with washed organic cotton.

Agnieszka Depta
Paper conservator
London



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                  Conservation DistList Instance 30:6
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