Naphthol Green B is a chemical compound, a green synthetic dye also known as Acid Green 1, D&C Green No. 1, CI 10020

Chemical name: Trisodium tris[5,6-dihydro-5-(hydroxyimino)-6-oxonaphthalene-2-sulphonato (2-) N5,O6]ferrate(3-)

What it is used for and where

Cosmetics

It is a restricted cosmetic ingredient as   IV/2 and II/1342   when used as a substance in hair dye products, a Relevant Item in the Annexes of the European Cosmetics Regulation 1223/2009. Substance or ingredient reported: Trisodium tris[5,6-dihydro-5-(hydroxyimino)-6-oxonaphthalene-2-sulphonato(2-)-N5,O6]ferrate(3-).

It is an ingredient that makes the final product more attractive from an aesthetic point of view, but can pose a potential health risk with undesirable side effects especially when used continuously as it can be absorbed through the skin or mucous membranes.

Safety

It is an ingredient that has some important health-related contraindications: it should not come into contact with mucous membranes.

Molecular Formula   C₃₀H₁₈FeN₃NaO₆

CAS   19381-50-1

EC number    243-010-2

Synonyms: 

Acid Green 1

CI 10020

D&C Green No. 1

trisodium;6-hydroxy-5-nitrosonaphthalene-2-sulfonate;iron

MFCD00003886

sodium tris(1-nitroso-6-sulfonatonaphthalen-2-yloxy)iron