METHOD FOR PRODUCING LIQUID CRYSTALLINE POLYESTER FIBER, LIQUID CRYSTALLINE POLYESTER FIBER, RUBBER-REINFORCING MATERIAL, TIRE CORD AND TIRE

摘要

PROBLEM TO BE SOLVED: To produce liquid crystalline polyester fibers stably for a long time period.;SOLUTION: A step of preparing liquid crystalline polyester includes acylation of at least one phenolic hydroxyl group containing compound selected form a group consisting of aromatic diols and aromatic hydroxycarboxylic acids with an aliphatic anhydride to obtain a corresponding acylated compound, and transesterification of the acylated compound and at least one compound selected form a group consisting of aromatic dicarboxylic acids and aromatic hydroxycarboxylic acids to obtain liquid crystalline polyester. On this occasion, at least one of the acylation and the transesterification is carried out in the presence of a heterocyclic organic base compound containing two or more nitrogen atoms. Then, fibers are obtained by melt spinning of liquid crystalline polyester having a flow-starting temperature of from 305°C to 380°C at a temperature equal to or higher than a temperature at which the liquid crystalline polyester shows a melt viscosity of 70 Pa s measured under a specific condition and lower than 370°C.;COPYRIGHT: (C)2012,JPO&INPIT