METHOD FOR PRODUCTION OF POLYAMIDE MONOFILAMENT Russian patent published in 1995 - IPC

FIELD: method for production of man-made fibers. SUBSTANCE: polyamide melt is extruded through spinneret. Formed filaments are taken up on rotating cylinder where filament is first cooled down to temperature to temperature 30-150 C below the temperature of maximum crystallization rate by single-side contact with surface of take-up cylinder. Then, filament is separated from cylinder surface and finally cooled during the second stage down to temperature 3-30 C below the glass transition temperature of dry nonoriented polyamide by alternate contact of opposite sides with surfaces of subsequent cylinders which simultaneously serve as feeding mechanism of the first draw device where filament is subjected to orientation drawing. Then, filament is subjected to thermal stabilization and wound up on take-up device. EFFECT: improved mechanical and physical properties of monofilament in a wide range of temperatures. 2 cl