Is Naphthalene Blue Black CS vegan?

Naphthalene Blue Black CS

Vegan

Naphthalene Blue Black CS is a synthetic azo dye used in the textile industry for dyeing wool and other fibres, known also as Blauschwartz NSF and Acid Black 41.

Also known as Acid Black 41, Blauschwartz NSF
CAS number 5850-37-3
CI number CI 20480
Last reviewed 3 June 2026

Sources

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