Paraloid B72

I'm having problems with Paraloid B72 mixed with alcohol as a
fixative for a blue pigment of a book of the 16th century. It seems
that the pigment loses is natural brightness and turns opaque (it
seems that have a white film upon the letters of the text). I don't
know why this happens and what can I use as a substitute (perhaps
hydroxy methylcellulose?)

Teresa Lanca
Biblioteca Nacional
Portugal


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                  Conservation DistList Instance 15:37
                 Distributed: Monday, November 12, 2001
                       Message Id: cdl-15-37-016
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