Toray Industries, Inc.

Shizuo Watanabe

Atsushi Sumida

Ryuichi Yamamoto

Kosuke Katsuki

Keiichiro Ozaki

Carbon fiber superior in processability and in physical properties as a composite is obtained by treating carbon fiber with an epoxy resin composition incorporating a polyalkylene ether glycol derivative represented by the following general formula (I) or (II): ##STR1## wherein R.sub.1 is alkylene of C.sub.1 to C.sub.30, R.sub.2 is alkyl of C.sub.1 to C.sub.30, R.sub.3 and R.sub.4 are each hydrogen or methyl, R.sub.5 is glycidyl, X is ether linkage (--O--) or ester linkage ##STR2## m and n are integers of 1 to 20.

Carbon fiber and process for preparing same

A method of producing carbon fibers in which an exhaust gas generated in a heat-treating stage of the production of carbon fibers is divided into two portions, one portion thereof being decomposed by the action of an oxidizing catalyst and subsequently being blended with the other portion, to be reused. According to said method, the heat loss in the exhaust gas disposal process can be substantially reduced and the efficiency of heat-treating can be improved and in consequence, various troubles due to the decomposed products contained in the heat-treating atmosphere such as surface damage, fuzziness and individual fiber breakage, etc. can be avoided.

Method of producing carbon fibers

An improved process for manufacturing high-grade and high-quality graphite fibers by the steps of (a) heating carbon fibers from acrylic fibers in an initial heating zone while exposed to an atmosphere of inert gas having a maximum temperature from about 1700.degree. C. to 1900.degree. C., and (b) then heating the resulting fibers in a subsequent heating zone while exposed to an atmosphere of inert gas having a maximum temperature from 2300.degree. C. to 2700.degree. C.

Process for continuous graphitization of graphitizable precursor fibers

Disclosed is an improvement in a process for producing oxidized fibers wherein precursor fibers comprised of oxidizable continuous filaments are repeatedly brought into or out of contact with the surface of a heated body, maintained at a temperature of from approximately 200.degree. to 400.degree. C., in an oxidizing gaseous atmosphere thereby to be oxidized. The oxidized fibers can then be heated in a non-oxidizing gaseous atmosphere maintained at a temperature of at least approximately 800.degree. C. to produce carbon fibers, if desired. The improvement resides in that an interlaced filament yarn is used as the precursor fibers, which yarn substantially has no crimps or loops and is comprised of continuous filaments entangled with each other along the longitudinal direction thereof to an extent such that the coherency factor of the yarn is in the range of from approximately 20 to 100.

Growing community of inventors

Ehime, Japan

Shizuo Watanabe