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. 01, 1997
Filed:
Jun. 30, 1995
Takashi Kojima, Ibaraki-ken, JP;
Yasuhiro Hirai, Ibaraki-ken, JP;
Takafumi Yoshimura, Ibaraki-ken, JP;
Mitsubishi Gas Chemical Company, Inc., Tokyo, JP;
Abstract
Mesophase pitch that has a softening point of no more than 250.degree. C., a pyridine-insolubles content of no more than 50% and a n-heptane solubles content of 3-10%, with the n-heptane solubles experiencing a weight loss of no more than 15% at 450.degree. C. as measured by thermogravimetry is produced by polymerizing a condensed polycyclic aromatic hydrocarbon or a substance containing it in the presence of HF and BF.sub.3. This mesophase pitch is suppressed satisfactorily in its tendency to smoke during spinning and, additionally, it has a low enough softening point to exhibit outstanding spinnability. Hence, the pitch allows for high-volume spinning to be performed continuously for a prolonged time without causing extensive fouling of the surface of spinning nozzles.