Patent ID: 7943071
Filing Date: 2011-05-17
Classification: D01D,D01F,Y10T

Abstract:
1. A process for preparing a polyethylene terephthalate monofilament comprising the steps of: spinning a polyethylene terephthalate chip having an intrinsic viscosity of 0.8 to 1.3 through a nozzle having 192˜384 orifices, passing the spun yarn from the nozzle through a hood heater adjusted to 350˜400° C. and extended to 320˜500 mm, quenching the yarn from the hood heater, oiling the quenched yarn, and drawing in a multistep process using a plurality of godet rollers on which the contact areas between the yarn and the second godet rollers for the primary drawing is adjusted to 4,000˜8,000 mm wherein the contact area is determined by the following equation: wherein the polyethylene terephthalate monofilament so produced gives a stress-strain curve exhibiting an elongation of less than 2.5% at an initial stress of 2.0 g/d, with an initial modulus value of 80 to 160 g/d, an elongation of 7.5% or less in a stress range of from 2.0 g/d to 9.0 g/d, and an elongation of at least 2.0% or more in a stress range of from 10.0 g/d to the point of break.