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:
Aug. 07, 2012
Filed:
Dec. 10, 2008
Taro Oyama, Sunto-gun, JP;
Rie Kawahito, Sunto-gun, JP;
Hiroshi Kimura, Sunto-gun, JP;
Toho Tenax Co., Ltd., Tokyo, JP;
Abstract
There is disclosed a method of producing a pre-oxidation fiber in the production of the pre-oxidation fiber by subjecting a polyacrylic precursor fiber to pre-oxidation processing in an oxidizing atmosphere, including shrinking the precursor fiber as a pretreatment of pre-oxidation at a load of 0.58 g/tex or less in the temperature range of 220 to 260° C. under conditions in which the degree of cyclization (I/I) of the precursor fiber measured by a Fourier transform infrared spectrophotometer (FT-IR) does not exceed 7%, initially-drawing the precursor fiber at a load of 2.7 to 3.5 g/tex in an oxidizing atmosphere at 230 to 260° C. in the ranges of the degree of cyclization of not exceeding 27% and of the density of not exceeding 1.2 g/cm, and then subjecting the pre-oxidation fiber to pre-oxidation treatment. A carbon fiber of high strength and high elasticity that is appropriate for composite materials that exhibit high composite performance is obtained by continuously subjecting this pre-oxidation fiber to carbonization treatment.