Anthraquinone dyesRUBIARUBIA CORDIFOLIA (INDIAN MADDER)
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1,3-Dihydroxyanthraquinone, also called purpuroxanthin or xanthopurpurin, is an organic compound with formula C14H8O4 that occurs in the plant Rubia cordifolia (Indian madder). It is one of ten dihydroxyanthraquinone isomers. Its molecular structure can be viewed as being derived from anthraquinone by replacement of two hydrogen atoms (H) by hydroxyl groups (-OH). Xanthopurpurin occurs in small amounts (as a glycoside) in the root of the common madder plant, Rubia tinctorum,Continue Reading

Anthraquinone dyesCobaltRUBIASeeing RedYellow
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1,2,4-Trihydroxyanthraquinone, commonly called purpurin, is an anthraquinone. It is a naturally occurring red/yellow dye. It is formally derived from 9,10-anthraquinone by replacement of three hydrogen atoms by hydroxyl (OH) groups. Purpurin is also called verantin, smoke Brown G, hydroxylizaric acid, and C.I. 58205. It is a minor component of the classical lake pigment “madder lake” or Rose Madder. History Madder root has been used forContinue Reading