Crocetin
Revision as of 12:21, 27 April 2013 by (username removed)
Description
A bright yellow natural dyestuff. Crocetin is the primary colorant in saffron, crocus, wongsky, unki, gunari, and flowers of Nyctanthes arbor-tristis. Crocetin is a dye substantive dye that produces a strong yellow color on alum mordanted and unmordanted wool. Copper mordanting produces a greenish yellow shade.
Synonyms and Related Terms
8,8'-diaporcarotenedioic acid; CI 75100; crocetina (Esp., It., Port.)
Other Properties
Soluble dilute alkali solutions and pyridine. Slightly soluble in water, organic solvents.
Forms a blue solution in concentrated sulfuric acid.
Forms dark red crystals from acetic anhydride extract.
Abs. max 464, 436, 411 nm
| Composition | C20H24O4 |
|---|---|
| CAS | 27876-94-4 |
| Melting Point | 285 |
Authority
- Helmut Schweppe, Helmut Schweppe, Schweppe color collection index and information book
- The Merck Index, Martha Windholz (ed.), Merck Research Labs, Rahway NJ, 10th edition, 1983 Comment: entry 2578
- Colour Index International online at www.colour-index.org
- Judith Hofenk-de Graaff, Judith Hofenk-de Graaff, Natural Dyestuffs: Origin, Chemical Constitution, Identification, Central Research Laboratory for Objects of Art and Science, Amsterdam, 1969