2-Naphthalenecarboxylic acid, 4-((2,5-dichloro-3-methyl-6-sulfophenyl)azo)-3-hydroxy-, calcium salt (1:1) 4-((2,5-Dichloro-3-methyl-6-sulfophenyl)azo)-3-hydroxy-2-naphthalenecarboxylic acid, calcium salt (1:1) 67906-56-3 Calcium 4-((2,5-dichloro-3-methyl-6-sulphonatophenyl)azo)-3-hydroxy-2-naphthoate EINECS 267-723-3