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:
May. 20, 1986
Filed:
Dec. 27, 1984
Applicant:
Inventors:
Kozo Yudate, Chiba, JP;
Yukihiro Ohsugi, Chiba, JP;
Mamoru Kamishita, Chiba, JP;
Ken Nagasawa, Chiba, JP;
Assignee:
Other;
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
C10C / ; C10C / ; D01F / ;
U.S. Cl.
CPC ...
208 44 ; 208 39 ; 208 22 ; 4234474 ;
Abstract
A method of producing a precursor pitch for use in the production of carbon fibers, which comprises hydrogenating a soft or middle tar pitch to obtain a hydrogenated pitch containing no free carbon and high molecular weight components and then subjecting it to a heat treatment. In this method, the hydrogenation is carried out in the presence of tetralin at a temperature of 400.degree.-450.degree. C., and the heat treatment after the removal of solvent insoluble components and solvent is carried out in an inert gas atmosphere at a temperature of 450.degree.-500.degree. C. and under a reduced pressure of 0.1-10 Torr.