PRODUCTION OF CARBON FIBER HAVING ELLIPTIC CROSS-SECTION

摘要

PURPOSE:To obtain a high-performance carbon fiber having elliptic cross-section, by extruding a spinning pitch through a nozzle having a specific die shape, sufficiently relaxing the extrudate immediately after extrusion, continuously winding the extruded fiber and infusibilizing and carbonizing the product. CONSTITUTION:A pitch for spinning is extruded through a nozzle having rectangular or modified cross-section. The width/height ratio of the die of said nozzle is >=1. The pitch molecule oriented by the nozzle is sufficiently relaxed immediately after the extrusion from the nozzle and continuously wound to obtain a pitch fiber having elliptic cross-section. The objective carbon fiber is produced by infusibilizing and carbonizing the pitch fiber.