Golf club shaft and golf club

Abstract

A golf club shaft is formed by curing wound fiber-containing prepregs and has a tip side and a butt side. In an embodiment, the prepregs include pitch-based carbon fiber-containing prepregs with a low elastic modulus, which are wound on the tip side, and polyacrylonitrile (PAN) based carbon fiber-containing prepregs, which are wound in an outermost layer on the tip side. In another embodiment, the prepregs include low-elasticity carbon fiber-containing prepregs wound on the tip side, and high-elasticity carbon fiber-containing prepregs wound on the butt side. In yet another embodiment, the prepregs include low-elasticity carbon-containing prepregs, which are wound on the butt side, and high elasticity carbon-containing prepregs, which are wound on the tip side.

What is claimed is: 
     
         1 . A golf club shaft having a tip side and a butt side and being formed by curing wound fiber-containing prepregs, the wound fiber-containing prepregs comprising:
 pitch-based carbon fiber-containing prepregs with a low elastic modulus, which are wound on the tip side; and   polyacrylonitrile-based carbon fiber-containing prepregs, which are wound in an outermost layer on the tip side.   
     
     
         2 . The shaft according to  claim 1 , wherein the wound fiber-containing prepregs further comprises polyacrylonitrile-based carbon fiber-containing prepregs extending continuously from the tip side to the butt side of the golf club shaft. 
     
     
         3 . A golf club comprising:
 the golf club shaft according to  claim 1 ; and   a head.   
     
     
         4 . A golf club shaft having a tip side and a butt side and being formed by curing wound fiber-containing prepregs, the wound fiber-containing prepregs comprising:
 low-elasticity carbon fiber-containing prepregs wound on the tip side; and   high-elasticity carbon fiber-containing prepregs wound on the butt side.   
     
     
         5 . The shaft according to  claim 4 , wherein the wound fiber-containing prepregs further comprises:
 main prepregs extending continuously from the tip side to the butt side of the golf club shaft and comprising polyacrylonitrile-based carbon fibers which are oriented in a strait direction with respect to a longitudinal direction of the shaft; and   bias prepregs extending continuously from the tip side to the butt side of the golf club shaft and comprising polyacrylonitrile-based carbon fibers which are oriented in a bias direction with respect to the longitudinal direction of the shaft.   
     
     
         6 . The golf club shaft according to  claim 5 , wherein the low-elasticity carbon fibers have a tensile elastic modulus of 5 to 20 ton·f/mm 2 , the high-elasticity carbon fibers have a tensile elastic modulus of 40 to 80 ton·f/mm 2 , the main prepregs have a tensile elastic modulus of 10 to 80 ton·f/mm 2 , and the bias prepregs have a tensile elastic modulus of 40 to 46 ton·f/mm 2 . 
     
     
         7 . The golf club shaft according to  claim 4 , wherein the high-elasticity carbon fiber-containing prepregs have a length from 15 to 45% of the entire length of the shaft on the butt side. 
     
     
         8 . The golf club shaft according to  claim 4 , wherein the low-elasticity carbon fiber-containing prepregs have a length from 5 to 45% of the entire length of the shaft on the tip side. 
     
     
         9 . A golf club comprising:
 the golf club shaft according to  claim 4 ; and   a head.   
     
     
         10 . A golf club shaft having a tip side and a butt side and being formed by curing wound fiber-containing prepregs, the wound fiber-containing prepregs comprising:
 low-elasticity carbon-containing prepregs wound on the butt side; and   high elasticity carbon-containing prepregs wound on the tip side.   
     
     
         11 . The golf club shaft according to  claim 10 , wherein the wound fiber-containing prepregs further comprise:
 main prepregs extending continuously from the tip side to the butt side of the golf club shaft and comprising polyacrylonitrile-based carbon fibers which are oriented in a straight direction with respect to a longitudinal direction of the shaft; and   bias prepregs extending continuously from the tip side to the butt side of the golf club shaft and comprising polyacrylonitrile-based carbon fibers which are oriented in a bias direction with respect to the longitudinal direction of the shaft.   
     
     
         12 . The golf club shaft according to  claim 11 , wherein the low-elasticity carbon fibers have a tensile elastic modulus of 5 to 20 ton·f/mm 2 , the high-elasticity carbon fibers have a tensile elastic modulus of 10 to 80 ton·f/mm 2 , the main prepregs have a tensile elastic modulus of 10 to 80 ton·f/mm 2 , and the bias prepregs have a tensile elastic modulus of 40 to 60 ton·f/mm 2 . 
     
     
         13 . The golf club shaft according to  claim 10 , wherein the high-elasticity carbon fiber-containing prepregs have a length from 5 to 45% of the entire length of the shaft on the tip side. 
     
     
         14 . The golf club shaft according to  claim 10 , wherein the low-elasticity carbon fiber-containing prepregs have a length from 15 to 45% of the entire length of the shaft on the butt side. 
     
     
         15 . A golf club comprising:
 the golf club shaft according to  claim 10 ; and   a head.