2,7-Naphthalenedisulfonic acid, 4-hydroxy-3-((4'-((4-hydroxyphenyl)azo)-3,3'-dimethyl(1,1'-biphenyl)-4-yl)azo)-, disodium salt 68109-58-0 Disodium 4-hydroxy-3-((4'-((4-hydroxyphenyl)azo)-3,3'-dimethyl(1,1'-biphenyl)-4-yl)azo)naphthalene-2,7-disulphonate EINECS 268-478-5