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:
Feb. 15, 1994
Filed:
Nov. 20, 1992
Kozi Nishida, Otake, JP;
Yukio Kasabo, Otake, JP;
Toshihiro Maxima, Otake, JP;
Yoshio Manabe, Otake, JP;
Osamu Kato, Toyama, JP;
Mitsubishi Rayon Co., Ltd., Tokyo, JP;
Abstract
There are disclosed a method of purifying a polyacrylonitrile which comprises removing iron compounds or ions thereof and aluminum compounds or ions thereof which can be contained as impurities in a polyacrylonitrile obtained by aqueous suspension polymerization using an inorganic redox initiator, from a solution consisting of said polyacrylonitrile and an organic solvent capable of dissolving said polyacrylonitrile, by the use of a substance having ion-exchanging ability which is insoluble in said organic solvent; a process for producing fiber from the polyacrylonitrile thus purified; and a process for producing carbon fiber from said fiber.