Multilayer solid golf ball

Abstract

A multilayer solid golf ball may include a core formed from a highly neutralized polymer and a cover surrounding the core. The ball may also include an enclosing layer disposed between the core and the cover, the enclosing layer having a thermal conductivity of 0.12 W/m-K or less.

1 - 20 . (canceled) 
     
     
         21 . A method for making a multilayer golf ball, comprising:
 forming a solid core from a highly neutralized polymer;   forming a enclosing layer around the core, the enclosing layer being a solid material having a thickness of 0.01 mm to 0.4 mm, the solid material comprising ethylene vinyl acetate copolymer; and   providing a cover surrounding the enclosing layer to form the golf ball;   wherein a thermal conductivity of the enclosing layer is less that a thermal conductivity of the cover.   
     
     
         22 . A method according to  claim 21 , wherein the thermal conductivity of the enclosing layer is 0.12 W/m-K or less. 
     
     
         23 . A method according to  claim 21 , wherein the solid material of the enclosing layer is formed from a mixture of ethylene vinyl acetate copolymer, methyl ethyl ketone, and methylcyclohexane. 
     
     
         24 . A method according to  claim 21 , wherein the thermal conductivity of the enclosing layer is such that after exposing the golf ball to air of 0° C. for 30 minutes the golf ball has a coefficient of restitution that is at least 94.4 percent of a coefficient of restitution of the golf ball before the exposing. 
     
     
         25 . A method according to  claim 21 , wherein the enclosing layer has a thickness of about 0.02 mm. 
     
     
         26 . A method according to  claim 21 , further comprising forming an intermediate layer around the core before forming the enclosing layer around the intermediate layer and the core, or forming the intermediate layer around the enclosing layer and the core, wherein the intermediate layer is formed of a solid material and a thermal conductivity of the intermediate layer is greater than the thermal conductivity of the enclosing layer. 
     
     
         27 . A method according to  claim 21 , wherein the solid material of the enclosing layer consists essentially of the ethylene vinyl acetate copolymer. 
     
     
         28 . A method according to  claim 21 , wherein the enclosing layer is formed directly in contact with the core. 
     
     
         29 . A multilayer golf ball, comprising a solid core, a solid enclosing layer comprising ethylene vinyl acetate copolymer, and a cover, wherein the multilayer golf ball is formed by steps of:
 forming the solid core from a highly neutralized polymer;   forming the enclosing layer around the solid core, the enclosing layer being formed of a solid material and having a thickness of 0.01 mm to 0.4 mm; and   surrounding the enclosing layer with the cover, thereby providing the golf ball;   
       wherein a thermal conductivity of the enclosing layer is less that a a thermal conductivity of the cover. 
     
     
         30 . A multilayer golf ball according to  claim 29 , wherein the thermal conductivity of the enclosing layer is 0.12 W/m-K or less. 
     
     
         31 . A multilayer golf ball according to  claim 29 , wherein the thermal conductivity of the enclosing layer is such that after exposing the golf ball to air of 0° C. for 30 minutes the golf ball has a coefficient of restitution that is at least 94.4 percent of a coefficient of restitution of the initial golf ball before the exposing. 
     
     
         32 . A multilayer golf ball according to  claim 29 , wherein the enclosing layer has a thickness of about 0.02 mm. 
     
     
         33 . A multilayer golf ball according to  claim 29 , further comprising an intermediate layer formed around the core wherein the intermediate layer is in direct contact with the core and the enclosing layer is in direct contact with the intermediate layer, or an intermediate layer formed around the core and the enclosing layer wherein the enclosing layer is in direct contact with the core and the intermediate layer is in direct contact with the enclosing layer, and wherein a thermal conductivity of the intermediate layer is greater than the thermal conductivity of the enclosing layer. 
     
     
         34 . A multilayer golf ball according to  claim 29 , wherein the solid material of the enclosing layer consists essentially of the ethylene vinyl acetate copolymer. 
     
     
         35 . A multilayer golf ball according to  claim 29 , wherein the enclosing layer is directly in contact with the core.