SIZING AGENT-APPLIED CARBON FIBER, PRODUCTION METHOD THEREOF, PREPREG, AND CARBON FIBER-REINFORCED COMPOSITE MATERIAL

摘要

PROBLEM TO BE SOLVED: To provide a sizing agent-applied carbon fiber which allows adhesiveness and anti-abrasion properties between a carbon fiber and a matrix resin to be excellent and allows a composite to be excellent in high-order processability, and to provide a production method of the sizing agent-applied carbon fiber, a prepreg, and a carbon fiber-reinforced composite material.SOLUTION: The sizing agent-applied carbon fiber is obtained by applying a sizing agent, which contains an aliphatic epoxy compound (A) and at least an aromatic epoxy compound (B1) as an aromatic compound (B), to the carbon fiber and has 335-600 GPa elastic modulus. The surface oxygen concentration (O/C), which is measured by the X-ray photoelectron spectroscopy using AlKαas an X-ray source and 45° as a photoelectron escape angle and is an atomic number ratio of the oxygen (O) on the surface of the sizing agent-applied carbon fiber to the carbon (C) thereon, is 0.15 or larger. When the C1s inner shell spectrum on the surface of the sizing agent applied to the carbon fiber is measured by the X-ray photoelectron spectroscopy using AlKα1,2 as the X-ray source and 15° as the photoelectron escape angle, a ratio ((a)/(b)) of the height (cps) of a component of the bond energy (284.6 eV) belonging to (a) CHx, C-C and C=C (a) to that (cps) of another component of the bond energy (286.1 eV) belonging to (b) C-O is 0.50-0.80.