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.
Type:
Grant
Filed:
December 27, 1984
Date of Patent:
May 20, 1986
Inventors:
Kozo Yudate, Yukihiro Ohsugi, Mamoru Kamishita, Ken Nagasawa