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:
Mar. 18, 1986
Filed:
Aug. 05, 1983
Hugh E Redick, Simpsonville, SC (US);
E. I. Du Pont de Nemours and Company, Wilmington, DE (US);
Abstract
The oxidation of carbon fibers from pitch is carried out directly by winding the spun fibers on to a spinning spool or bobbin, said spool comprising an open ended, porous, non-expanding or collapsible spool. The spun carbon fibers are wound on such a spinning spool so as to leave open areas between fiber bundles. A mixture of an inert gas such as air or nitrogen containing a minor amount of oxygen is used as the oxidizing gas. Oxidation is carried out in a closed zone, e.g. an oven, for a period of time of at least 4 hours at a temperature that is initially below the glass transistion temperature of the carbon fibers and is slowly increased over the oxidation time to a maximum of about 340.degree. C. The gaseous oxidation atmosphere is continuously recycled and passed through the spool to ensure that the fibers are essentially completely oxidized.