PRODUCTION OF POLYAMIDE HIGH-STRENGTH YARN

• Main Authors: MATSUZAKI HATSUO, OKANO RYOJI, SHIRAI YASUHIRO
• Format: Patent
• Language: English
• Published: 15.10.1996
• Edition: 6
• Subjects: APPARATUS SPECIALLY ADAPTED FOR THE MANUFACTURE OF CARBONFILAMENTS; CHEMICAL FEATURES IN THE MANUFACTURE OF ARTIFICIAL FILAMENTS,THREADS, FIBRES, BRISTLES OR RIBBONS; CRIMPING OR CURLING FIBRES, FILAMENTS, THREADS, ORYARNS; MECHANICAL FINISHING OF YARNS OR ROPES; MECHANICAL METHODS OR APPARATUS IN THE MANUFACTURE OFARTIFICIAL FILAMENTS, THREADS, FIBRES, BRISTLES ORRIBBONS; NATURAL OR ARTIFICIAL THREADS OR FIBRES; PERFORMING OPERATIONS; PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL; SEPARATION; SPINNING; TEXTILES; TRANSPORTING; WARPING OR BEAMING; YARNS; YARNS OR THREADS

PURPOSE: To efficiently produce a high-grade and fine-size polyamide multifilament yarn having <=6 de single filament size of single filaments constituting the multifilament yarn, a high strength and toughness without any yarn breakage with high spinning stability. CONSTITUTION: A polyamide is melted at a temperature where the melt temperature T ( deg.C) and the crystallizing temperature Tc ( deg.C) according to the differential scanning colorimetry(DSC) satisfy conditions of 55 deg.C<=T-Tc<=75 deg.C and then melt-spun by using a spinneret pack having 10-150cm volume of a flow passage 1a in the pack on a filter 2 comprising a metallic nonwoven fabric. The surface roughness of the flow passage 1a and other flow passages in the pack of the spinneret pack is regulated to <=0.5S and a rectifying plate 3 is installed under the filter 2 of the spinneret pack to pass the molten polymer through holes 3a of the rectifying plate 3 at 2×10 to 5×10 sec<-1> flow velocity.