CRIMPED MULTIFILAMENT AND PRODUCTION THEREOF.

摘要

Crimped multifilament produced from thermoplastic polymer, birefringence measured at outer layer pt. of constituent monofilament is larger than that measured at central part thereof, distribution of birefringence is so postion of smallest birefringence is deviated from centre of fibre axis, and number of random crimps per unit is at least ten. Deg. of crystal growth as determined by wide-angle X-ray diffractometry is at least 0.2 in case of polyamide and at least 0.4 in case of polyester. Pref. method of producing crimped multifilament comprises cooling multifilaments extruded through spinnerets to given temp. by applying aq. liq. to side of each of multifilaments, stretching them 1.0- to 1.5- fold, and subjecting them to liq. jet treatment (in case of nylon) or relaxation heat treatment at 105 deg.C or above.