Is Thioindigo vegan?

Thioindigo

Vegan

Thioindigo is a synthetic organosulfur dye used to dye polyester fabric. It is structurally related to the plant-derived dye indigo, with the two NH groups replaced by two sulfur atoms, producing a pink shade. It is manufactured entirely from synthetic precursors.

Also known as DyStar, Vat Red 41
CAS number 522-75-8
CI number CI 73300
Last reviewed 3 June 2026

Sources

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