2,7-Naphthalenedisulfonic acid, 3-((2,4-dimethylphenyl)azo)-4-hydroxy-, disodium salt 4787-93-3 C.I. Acid Red 8, disodium salt Disodium 3-((2,4-dimethylphenyl)azo)-4-hydroxynaphthalene-2,7-disulphonate EINECS 225-337-2