POLYESTER FIBER AND PREPARATION METHOD THEREOF

摘要

PURPOSE: Polyester fiber is provided to have excellent physical properties by including filament of high strength and high elongation and low modulus, thereby minimizing the possibility of fracture under the extreme change of external environment. CONSTITUTION: Polyester fiber has the elongation of 0.5% or larger under the stress of 1.0 g/d measured, 4.3% or larger under the stress of 4.0 g/d, and 7.5% or larger under the stress of 7.0 g/d at room temperature. The total fineness is 900 denier or larger. The manufacturing method of the polyester fiber comprises: a step of elongate polyester fine elongation filament by melt spinning a polyester polymer of which inherent viscosity is 1.2d/g or more at 270-310°C. The polyester polymer comprises 70mol% or more of polyethylene terephthalate.