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. 06, 2012
Filed:
Oct. 31, 2008
Hidekazu Yoshikawa, Shizuoka, JP;
Taro Oyama, Shizuoka, JP;
Hiroshi Kimura, Shizuoka, JP;
Toho Tenax Co., Ltd., Tokyo, JP;
Abstract
A carbon fiber strand obtained by bundling 20,000-30,000 carbon fibers each having, in the surface thereof, creases which are parallel to the fiber-axis direction. In an examination with a scanning probe microscope, the creases in the carbon fiber surface are apart from each other at a distance of 120-160 nm and have a depth of 12-23 nm, excluding 23 nm. The carbon fibers have an average fiber diameter of 4.5-6.5 nm, specific surface area of 0.9-2.3 m/g, and density of 1.76 g/cmor higher. The carbon strand has a tensile strength of 5,900 MPa or higher and a tensile modulus of 300 GPa or higher. When would on a bobbin at a tension of 9.8 N, the strand on the bobbin has a width of 5.5 mm or larger. When the carbon fiber strand is examined by a strand splitting evaluation method in which the strand is caused to run through three stainless-steel rods while applying a tension of 9.8 N thereto, no strand splitting is observed.