METHOD FOR MANUFACTURING FINE DENIER POLYESTER HOLLOW PRE-ORIENTED YARN AND THE YARN MANUFACTURED FROM THE SAME

摘要

PURPOSE: Fine denier polyester hollow pre-drawn yarn is provided which has a ultimate elongation of 70-180%, a single yarn fineness of 0.3-2.5d, a hollow ratio of 25-40%, a uster half inert value of under 0.3% and a heat stress variation between spindles of under 4% of. After drawing, the fine denier polyester hollow pre-drawn yarn has a single yarn fineness of 0.2-1.0d, a hollow ratio 25-40%, a ultimate elongation of 15-45% and a uster half inert value of under 0.3%. A manufacturing method thereof is provided. CONSTITUTION: Fine denier polyester hollow pre-drawn yarn is obtained by the steps of: preparing polyester polymer having an inherent viscosity of 0.5-0.7 and a melting point of 245-265deg.C; and hot-melting the polyester polymer, wherein (a) the melted polyester is extruded and discharged through discharge holes arranged on multi-ring type to discharge tow(4) uniformly (D2 is the diameter of the external ring and D1 is the diameter of the internal ring); (b) the tow(4) passes through a calm zone of Ls(mm) set on the lower part of a spinning nozzle(3); the tow(4) passes through a cylindrical cooling drum(5) having a diameter of Do(mm) and a length of Lq(cm) and supplying the cooling air from the inside to the outside; a cooling wind is supplied to the tow(4) at a speed of about 0.2-0.6m/s to cool the tow(4) to under glass transition temperature of the polyester polymer and collect it; and (c) the tow is wound at a speed of 1800-4000m/min.