Golf ball incorporating an innermost aspherical hollow portion

Abstract

Golf ball comprising a core and a cover, the core comprising: an innermost aspherical hollow portion having volume V ahp ; a shell layer formed from thermoplastic/thermoset composition and having inner surface comprising plurality of symmetrically spaced extensions that border and define the shape of the innermost aspherical hollow portion; the plurality of extensions and innermost aspherical hollow portion, combined, forming a phantom sphere having diameter of about 0.15-1.1 inches; the plurality of extensions having combined volume E TV such that V ahp ≧E TV >0.20 (E TV +V ahp ); and at least one thermoset/thermoplastic outer core layer disposed about the shell layer. The cover may comprise one or more layers. In one embodiment, the plurality of symmetrically spaced extensions border and define the shape of the innermost aspherical hollow portion, and the volume of the innermost aspherical hollow portion is about 2% to about 30% of a total volume of the golf ball.

What is claimed is: 
     
         1 . A golf ball comprising:
 a core comprising:
 an innermost aspherical hollow portion having a volume V ahp ; 
 surrounded by a shell layer that is formed from a thermoplastic composition and has an inner surface comprising a plurality of symmetrically spaced extensions that border and define a shape of the innermost aspherical hollow portion;
 wherein the plurality of extensions and innermost aspherical hollow portion, combined, form a phantom sphere having a diameter of from about 0.15 inches to about 1.1 inches; and 
 wherein the plurality of extensions have a combined total volume E TV  such that V ahp ≧E TV >0.20 (E TV +V ahp ); and 
 
 at least one outer core layer disposed about the shell layer; and 
   at least one cover layer disposed about the outer core layer;   wherein the inner surface has an inner surface hardness and the shell layer has an outer surface having an outer surface hardness greater than the inner surface hardness by about 0 to 5 Shore C to define a first hardness gradient; and   wherein the outer core layer has a second hardness gradient.   
     
     
         2 . The golf ball of  claim 1 , wherein the aspherical hollow portion has a shape that is axially symmetric. 
     
     
         3 . The golf ball of  claim 2 , wherein the aspherical hollow portion is at least one of non-spherical or irregularly-shaped. 
     
     
         4 . The golf ball of  claim 1 , wherein the plurality of extensions and innermost aspherical hollow portion, combined, form a spherical phantom sphere having a diameter of from about 0.30 inches to about 0.90 inches. 
     
     
         5 . The golf ball of  claim 1 , wherein the at least one cover layer comprises an inner cover layer disposed about the outer core layer, and an outer cover layer disposed about the inner cover layer, wherein the inner cover layer comprises an ionomeric material and has a first hardness and the outer cover layer comprises a polyurea or a polyurethane and has a second hardness less than the first. 
     
     
         6 . The golf ball of  claim 1 , wherein the innermost aspherical hollow portion, shell layer and outer core layer, combined, have an outer diameter of from about 0.75 inches to about 1.62 inches. 
     
     
         7 . The golf ball of  claim 1 , wherein the second hardness gradient is a negative hardness gradient of about 3 to 25 Shore C. 
     
     
         8 . The golf ball of  claim 1 , wherein the second hardness gradient is a positive hardness gradient of about 3 to 25 Shore C. 
     
     
         9 . The golf ball of  claim 1 , wherein the outer core layer is formed from a thermoset composition. 
     
     
         10 . The golf ball of  claim 1 , wherein at least one outer core layer is formed from a thermoplastic composition. 
     
     
         11 . A golf ball comprising:
 a core comprising:
 a shell layer that is formed from a thermoplastic composition and has an inner surface comprising a plurality of symmetrically spaced extensions that border and define a shape of an innermost aspherical hollow portion;
 wherein the innermost aspherical hollow portion comprise from about 2% to about 30% of a total volume of the golf ball; 
 
 at least one outer core layer disposed about the shell layer; and 
   at least one cover layer;   wherein the inner surface has an inner surface hardness and the shell layer has an outer surface having an outer surface hardness greater than the inner surface hardness by about 0 to 5 Shore C to define a first hardness gradient; and   wherein the outer core layer has a second hardness gradient.   
     
     
         12 . The golf ball of  claim 11 , wherein the aspherical hollow portion has a shape that is axially symmetric. 
     
     
         13 . The golf ball of  claim 12 , wherein the aspherical hollow portion is at least one of non-spherical or irregularly-shaped. 
     
     
         14 . The golf ball of  claim 11 , wherein the plurality of extensions and innermost aspherical hollow portion, combined, form a phantom sphere having a diameter of from about 0.15 inches to about 1.1 inches. 
     
     
         15 . The golf ball of  claim 11 , wherein the at least one cover layer comprises an inner cover layer disposed about the outer core layer, and an outer cover layer disposed about the inner cover layer, wherein the inner cover layer comprises an ionomeric material and has a first hardness, and the outer cover layer comprises a polyurea or a polyurethane and has a second hardness less than the first. 
     
     
         16 . The golf ball of  claim 11 , wherein the innermost aspherical hollow portion, shell layer and outer core layer, combined, have an outer diameter of from about 0.75 inches to about 1.62 inches. 
     
     
         17 . The golf ball of  claim 11 , wherein the second hardness gradient is a negative hardness gradient of about 3 to 25 Shore C. 
     
     
         18 . The golf ball of  claim 11 , wherein the second hardness gradient is a positive hardness gradient of about 3 to 25 Shore C. 
     
     
         19 . The golf ball of  claim 11 , wherein at least one outer core layer is formed from a thermoset composition. 
     
     
         20 . The golf ball of  claim 11 , wherein at least one outer core layer is formed from a thermoplastic composition.