The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jul. 09, 1991
Filed:
Mar. 15, 1990
Nitto Boseki Co., Ltd., Fukushima, JP;
Kawasaki Steel Corporation, Kobe, JP;
Abstract
The present invention relates to a process for producing a carbon fiber chopped strand which comprises preparing a pitch fiber from petroleum pitch or coal pitch, cutting the pitch fiber to a predetermined desired length, heating the cut pitch fiber at a high density accumulation in the atmosphere of an oxidative gas to infusibilize the cut pitch fiber, and then carbonizing and graphitizing the infusibilized fiber in an inert atmosphere. According to the process of the invention, no fuzz are formed on the fiber and no uneven infusibilization takes place. Further, the pitch fiber chopped strand accumulation has a high bulk density and relieve exothermic excursion naturally, and therefore neither combustion nor sticking takes place even in an oxidative atmosphere. Accordingly, the production speed can be enhanced and the cost can be lowered to a great extent.