A polyester fiber highly heat-resistant in a rubber matrix and useful as a reinforcing material for rubber articles, has a tensile strength of 8 g/d or more and is composed of a core portion made from a polyester resin and a skin portion made from a polyester resin and covering the core portion, the skin portion being in an amount of 5% to 20% based on the entire amount of the fiber and having a lower orientation and/or lower crystallinity than the core portion, which polyester fiber has been produced by treating a surface portion of a homogeneous polyester fiber consisting essentially of a polyester resin with a solvent capable of swelling the polyester resin or by coating a precursory polyester fiber for the core portion with a polyester resin for the skin portion.
一种在橡胶基体中具有高耐热性并可用作橡胶制品增强材料的聚酯纤维,其拉伸强度为 8 克/天或以上,由聚酯
树脂制成的芯部和聚酯
树脂制成并覆盖芯部的表皮部分组成,表皮部分的数量占纤维总量的 5%至 20%,其取向度和/或结晶度低于芯部,这种聚酯纤维是通过用能使聚酯
树脂溶胀的溶剂处理主要由聚酯
树脂组成的均质聚酯纤维的表皮部分,或用聚酯
树脂涂覆芯部的聚酯纤维前体以制成表皮部分而制成的。