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?  ...

Yes, the cotton was washed, twice the second time we tested it.  I
have had some emails from Mary Ballard suggesting that the sizing
may not wash out efficiently without enzymes to break down the
sizing, or may need a peroxide based oxidiser, or a hotter wash
water, depending on the sizing.  We have been using Orvus or similar
detergents, with no added enzymes or oxidisers, and a cooler water
wash.  Our plan is to try out the enzymes and a hotter wash,
followed by a wash in plain water with no detergents, and then redo
our Oddy tests.

Valerie Tomlinson
Conservator
Auckland War Memorial Museum
Tamaki Paenga Hira
The Domain
Private Bag 92018
Victoria Street West
Auckland 1142
New Zealand
+64 9 306 7070ext7304


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                  Conservation DistList Instance 30:5
                  Distributed: Saturday, June 18, 2016
                        Message Id: cdl-30-5-002
                                  ***