83784-01-4 EINECS 280-835-7 Tetrasodium 3-((2-methyl-4-(7-sulphonato-2H-naphtho(1,2-d)triazol-2-yl)phenyl)azo)-7-(6-sulphonato-2H-naphtho(1,2-d)triazol-2-yl)naphthalene-1,5-disulphonate