Blends of polyamide and acid anhydride-modified polyolefins for use in golf balls

Abstract

Multi-layered golf balls having at least one layer made of polyamide/acid anhydride-modified polyolefin blended compositions are provided. Preferably, a transparent polyamide is used. In one version, the composition comprises a blend of polyamide, acid anhydride-modified polyolefin, and plasticizer. The golf ball includes a core having at least one layer and a cover having at least one layer. The polyamide/acid anhydride-modified polyolefin composition may be used to form any core, cover, or other layer in the golf ball. In one preferred version, the polyamide/acid anhydride-modified polyolefin composition is used to form the inner core, and a rubber composition is used to form the outer core layer.

We claim: 
     
         1 . A golf ball, comprising:
 a) dual core comprising an inner and outer core layer, the inner core having an outer surface and geometric center and the outer core layer having an outer surface and inner surface; the inner core comprising a polyamide non-ionomeric composition, the polyamide composition comprising:
 i) about 40 to about 98% by weight polyamide; and 
 ii) about 1 to about 60% by weight of an acid anhydride-modified polyolefin, 
   
       and the outer core layer comprising a rubber composition, wherein the center of the inner core and surface of the outer core layer each has a hardness, and the surface hardness of the outer core layer is greater than the center hardness of the inner core; and
 b) a cover having at least one layer disposed about the core. 
 
     
     
         2 . The golf ball of  claim 1 , wherein the polyamide is a transparent polyamide. 
     
     
         3 . The golf ball of  claim 1 , wherein the polyamide composition further comprises a plasticizer. 
     
     
         4 . The golf ball of  claim 1 , wherein the center hardness of the inner core is about 15 Shore D or greater and the surface hardness of the outer core is about 40 Shore D or greater, the surface hardness of the outer core layer being greater than the center hardness of the inner core. 
     
     
         5 . A golf ball, comprising:
 a) a core comprising a rubber composition;   b) an inner cover layer disposed about the core; and   c) an outer cover layer disposed about the inner cover layer, the outer cover comprising a polyamide non-ionomeric composition, the polyamide composition comprising:
 i) about 40 to about 98% by weight polyamide; and 
 ii) about 1 to about 60% by weight of an acid anhydride-modified polyolefin. 
   
     
     
         6 . The golf ball of  claim 5 , wherein the polyamide is a transparent polyamide. 
     
     
         7 . The golf ball of  claim 5 , wherein the polyamide composition further comprises a plasticizer. 
     
     
         8 . The golf ball of  claim 5 , wherein the center hardness of the inner core is about 15 Shore D or greater and the surface hardness of the outer core is about 40 Shore D or greater, the surface hardness of the outer core layer being greater than the center hardness of the inner core.