for the following products
2,2'-Benzidinedisulfonic acid | 4,4'-Diamino-2,2'-biphenyldisulfonic acid | 4,4'-Diamino-[1,1'-biphenyl]-2,2'-disulfonic acid(contains 30% Water at maximum) | 4,4'-Diaminobenzidine-2,2'-disulfonic acid | 4,4'-Diaminobiphenyl-2,2'-disulfonic acid hydrate and Benzidine-2,2'-disulfonic acid
