METHOD OF PRODUCING CORE-SHEATH FIBER

摘要

PROBLEM TO BE SOLVED: To provide a method of producing core-sheath fiber capable of producing core-sheath fiber with high strength without using special raw material and/or special means, and to provide a method of producing fiber-reinforced resin with the core-sheath fiber.SOLUTION: A method of producing core-sheath fiber with a core part resin P1 having a melting temperature T1 and a sheath part resin P2 having a melting temperature T2 comprises the steps of: spinning core-sheath fiber by means of melt extrusion; maintaining temperature; and drawing. The melting temperature T1 is higher than the melting temperature T2 by 50°C or more, and the ratio of take-over speed to drawing speed is from 50 to 400 in the melt extrusion spinning process.