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Is 3-Hydroxy-4-[(2-Hydroxynaphthyl)azo]-7-Nitronaphthalene-1-Sulphonic Acid vegan?

3-Hydroxy-4-[(2-Hydroxynaphthyl)azo]-7-Nitronaphthalene-1-Sulphonic Acid

Vegan

This is a synthetic azo compound and its salts, used as a colorant in hair dye products.

Also known as 227-029-3, 5610-64-0
INCI name 3-Hydroxy-4-[(2-Hydroxynaphthyl)azo]-7-Nitronaphthalene-1-Sulphonic Acid
CAS number 16279-54-2
EC number 240-379-1
CosIng ID 31168
Last reviewed 4 July 2026

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