calcium 4-[(4-chloro-3-sulphonatophenyl)azo]-3-hydroxy-2-naphthoate;PIGMENT RED 58:2;EINECS 231-411-5;2-Naphthalenecarboxylic acid, 4-[(4-chloro-3-sulfophenyl)azo]-3-hydroxy-, calcium salt (1:1);C. I. Pigment Red 58:2;2-Naphthalenecarboxylic acid, 4-(2-(4-chloro-3-sulfophenyl)diazenyl)-3-hydroxy-, calcium salt (1:1)