Unki
Revision as of 07:18, 24 July 2013 by (username removed)
Description
A bright yellow natural dyestuff obtained from the fruit of the Gardinia florida that is native to the East Indies (Hofenk-de Graaf 1969). Unki has been used to dye silk a bright yellow color. The primary colorant in unki is crocetin. Crocetin is a substantive dye that is also found in saffron.
Other Properties
Crocetin is soluble in water, ethanol, alkali solutions. Crocetin forms a blue solution in concentrated sulfuric acid.
Additional Information
J.Hofenk-de Graaf, Natural Dyestuffs: Origin, Chemical Constitution, Identification, Central Research Laboratory for Objects of Art and Science, Amsterdam, September 1969.