To provide a carbon fiber reinforced composite material capable of being suitably used in a golf club shaft or the like and having high twist strength.
The tubular object is obtained by laminating at least one or more carbon fiber reinforced composite material layers and includes a bias layer wherein a carbon fiber direction is arranged at an angle of 25-65° with respect to the main axis of the tubular object and a straight layer laminated on the outer periphery of the bias layer and characterized in that the carbon fiber direction is arranged at an angle of 0-20° with respect to the main axis of the tubular object. The tensile modulus E (GPa) of the carbon fibers in the bias layer, the crystal size Lc () of a carbon net surface due to wide angle X-ray diffraction and the interlaminar shearing strength σ (MPa) of the carbon fiber reinforced composite material obtained by impregnating carbon fibers with an epoxy resin and heating and curing the impregnated carbon fibers satisfy a specific formula. The golf club shaft using the carbon fiber reinforced composite material is also disclosed.
FUJINO MUTSUKO
FUKUI HIROAKI
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