Yellow dye on Chinese paper

David Tremain's interesting posting on 7 May about red lead and
other pigments caused me to re-read an excellent article in Chemical
and Engineering News, August 11, 1997 entitled "Ancient Colors,
Modern Analyses".  Subscribers to the list may be interested to note
that the yellow dye used to dye the paper in the Diamond Sutra is
huangbo, derived from the Amur cork tree Phellodendron
amurense.  The two chemists researching the Diamond Sutra
explain that it was dyed yellow for two reasons--an edict by the
Chinese government required that all theological and socially
significantly papers must be dyed yellow (the Buddhist color of
solemnity) and because the dye also protected the paper from the
ravages of insects.  The dye is water soluble and contains three
yellow alkaloid chromophores: berberine, palmatine and jatorrhizine.

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                  Conservation DistList Instance 11:95
                   Distributed: Friday, May 22, 1998
                       Message Id: cdl-11-95-002
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