| abstract |
A polyester fiber having the following characteristics, and a method of manufacturing the same; (a) an intrinsic viscosity of between 0.45 and 0.85, (b) tan delta </=0.140 Tmax</=130 DEG C. wherein tan delta stands for a peak value of a dynamic loss tangent, and Tmax stands for a peak temperature, (c) E2/E1</=0.49 wherein E1 stands for an elongation from zero to a secondary yield point, and E2 stands for an elongation from the secondary yield point to a breaking point, (d) a stability coefficient expressed by a reciprocal value of a product of a work loss DELTA E at 150 DEG C. and a shrinkage factor under a dry heat at 175 DEG C., of 50 or more. A strength, a modulus of elasticity, and a resistance to fatigue of the polyester fiber in accordance with the present invention are superior, and a dimensional heat stability of this polyester fiber is remarkably improved. |