Chinese red

I have been contacted by a conservator without access to the list in
need of help. The conservator has for many years used potassium
methyl cyclohexyl oleate (a.k.a  Vulpex Liquid Soap) and Synperonic
N to cleanse textiles without problem.

Recently whilst washing a 17th century plant dyed green textile,
which had chinese red dyes, using a solution of potassium methyl
cyclohexyl oleate she found that the chinese red had changed to a
pale mauve. The solution shows no noticeable colour change, nor does
the green textile appear to have been discoloured anywhere else, it
is almost as though the colour has soaked into itself?

Are there any remedies that might bring back the original colour?
What might have caused the dies to fade and how might the
conservator address the problem of cleaning such material in the
future? Can anyone offer practical assistance, the conservator is
located in England.

Mark G. Vine
Conservation Resources
England

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                  Conservation DistList Instance 10:40
                 Distributed: Monday, October 21, 1996
                       Message Id: cdl-10-40-010
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