Crocetin

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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 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

Sources Checked for Data in Record

  • 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, Natural Dyestuffs: Origin, Chemical Constitution, Identification, Central Research Laboratory for Objects of Art and Science, Amsterdam, 1969