Process for dyeing polyamides in the melt

摘要

A process for dyeing spinnable polyamides in the melt, comprises incorporating into the melt a finely divided anthraquinone dyestuff of the formula where A represents an anthraquinone dyestuff and B represents an at least bicyclic non-vattable aryl residue. Specified polyamides are those derived from S -caprolactam, o -amino undecanoic acid and hexamethylene diamine and adipic acid. The dyeing may be effected before, during or after the formation of the polyamide. In the examples, polyhexamethylene adipamide is dyed with the following dyestuffs:- Specifications 516,131 and 820,975 are referred to.