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. 13, 1976
Filed:
Dec. 31, 1974
Takashi Fukuda, Otsu, JA;
Nobuo Ishizaki, Otsu, JA;
Shoichi Iwahori, Otsu, JA;
Masayoshi Shimada, Otsu, JA;
Toyobo Co., Ltd., , JA;
Abstract
A process for preparing active carbon fibers which comprises (a) providing a cellulose fiber with a phosphorus compound reactive thereto, (b) subjecting the resulting fiber to heat treatment at about 200.degree. to 350.degree.C until the decreased percentage of fiber becomes about 40 to 75 % (W/W) and then (c) subjecting the resultant fiber to activation treatment at about 450.degree. to 1000.degree.C in an atmosphere containing not less than about 5 % (V/V) of steam until the decreased percentage of fiber becomes about 65 to 95 % (W/W), the said phosphorus compound showing a residual percentage of phosphorus of not less than about 70 % (W/W) after the heat treatment of the step (b) and a residual percentage of phosphorus of not more than about 10 % (W/W) after the activation treatment of the step (c).