2-Naphthalenesulfonic acid, 7,7'-iminobis(3-((2,4-dimethylphenyl)azo)-4-hydroxy-, disodium salt 6420-38-8 7,7'-Iminobis(4-hydroxy-3-((2,4-dimethylphenyl)azo)-2-naphthalenesulfonic acid), disodium salt Disodium 7,7'-iminobis(3-((2,4-dimethylphenyl)azo)-4-hydroxynaphthalene-2-sulphonate) EINECS 229-159-6