2-Naphthalenecarboxylic acid, 3-hydroxy-4-((4-methyl-2-sulfophenyl)azo)-, calcium strontium salt (2:1:1) 55491-44-6 Calcium strontium bis(3-hydroxy-4-((4-methyl-2-sulphonatophenyl)azo)-2-naphthoate) EINECS 259-673-6