Dye Structure Relationships for Dyeing Metal- Containing Polypropylene

Abstract

Dyes containing the imino-azo structure C—N=N— are valuable for dyeing poly olefins which contain transition-metal additives. The transition metal forms strong complexes with the imino nitrogen and with the azo nitrogen atoms. In those cases where the dyed fibers are not fast to drycleaning, these complexes are strong enough to cause removal of the transition metal into the drycleaning medium. Thiazole-azo structures prepared from fused ring or polar substituted thiazoles exhibit good dry cleaning fastness.