Process for preparing wetfast polyamide fibers

摘要

A modified polyamide polymer having a high amino end group content, with more than 30 percent of the amino end groups being secondary or tertiary amine, dramatically improves the dye bleed performance. The modified polyamide may be prepared by polymerization of polyamide-forming monomers in the presence of a carboxylic acid and a hindered piperidine derivative in amounts sufficient to achieve the high amino end group content.