PROCESS OF PRODUCING POLYAMIDE MIDDLE-SHRINKAGE FILAMENTS

摘要

A method for manufacturing a polyamide-based middle-shrinkage filament is provided to improve the middle-shrinkage property of the filament while suppressing the deterioration in physical property of yarns, by optimizing the condition for spinning and winding the filament even without reforming a polymer or complementing a spinning apparatus. A polyamide-based middle-shrinkage filament is spun and wound by using a nylon-6 chip as a source under a condition having a spinning rate of 4,000-4,500 m/min, a draw ratio of 1.6-2.3, and a heat set temperature of 100-140°C. The nylon-6 chip is a full-dull type nylon-6 chip having an intrinsic viscosity of 2.45-2.50. The nylon-6 chip is vacuum-dried at a temperature of 90-120°C to contain a moisture content of 100-600 ppm.