Golf balls having translucent covers formed of aromatic and aliphatic polyurethanes

Abstract

Golf balls having multi-layered covers, wherein at least one of the cover layers is substantially transparent, are provided. The cover includes an inner cover layer made of an ionomer composition; an intermediate cover layer made of an aromatic polyurethane composition; and outer cover layer made of an aliphatic polyurethane composition, wherein the total thickness of the multi-layered cover is no greater than 0.110 inches. In one version, the outer cover layer is substantially transparent and the underlying intermediate cover layer is colored. In another version, both the outer and intermediate cover layers are substantially transparent. Light-reflective fillers such as pearlescent pigments, glitter, and metallics may be added to the cover layers. The resulting ball has pleasing decorative effects.

1 . A golf ball, comprising:
 a core, and   a multi-layered cover having three layers, the multi-layered cover comprising:
 i) an inner cover layer comprising an ionomer composition containing ethylene acid copolymer having acid groups such that at least 30% of the acid groups are neutralized, the ethylene acid copolymer being present in an amount of at least 10 weight percent; 
 ii) an outer cover layer comprising a first polyurethane composition containing aliphatic polyurethane, the aliphatic polyurethane being present in an amount of at least 10 weight percent; and 
 iii) an intermediate cover layer disposed between the inner cover layer and outer cover layer, the intermediate layer comprising a second polyurethane composition containing an aromatic polyurethane, the aromatic polyurethane being present in an amount of at least 10 weight percent, wherein the total thickness of the multi-layered cover is no greater than 0.110 inches and at least one of the cover layers is substantially transparent. 
   
     
     
         2 . The golf ball of  claim 1 , wherein the outer cover layer is substantially transparent. 
     
     
         3 . The golf ball of  claim 2 , wherein the outer cover layer and intermediate cover layer are substantially transparent. 
     
     
         4 . The golf ball of  claim 2 , wherein the intermediate cover layer comprises a sufficient amount of colorant so that the layer is colored and this colored layer is visible from the exterior of the ball. 
     
     
         5 . The golf ball of  claim 4 , wherein the colorant is selected from the group consisting of dyes, pigments, and mixtures thereof. 
     
     
         6 . The golf ball of  claim 1 , wherein the outer cover layer comprises light-reflective fillers selected from the group consisting of pearlescent pigments, glitter, metalized films and foils, and mixtures thereof. 
     
     
         7 . The golf ball of  claim 1 , wherein the intermediate cover layer comprises light-reflective fillers selected from the group consisting of pearlescent pigments, glitter, metalized films and foils, and mixtures thereof. 
     
     
         8 . The golf ball of  claim 6  or  7 , wherein the light-reflective fillers are pearlescent pigments selected from the group consisting of metalized pigments, mica-based pigments, borosilicate pigments, titanium dioxide pigments, iron oxide pigments, and mixtures thereof. 
     
     
         9 . The golf ball of  claim 1 , wherein the total thickness of the cover is no greater than 0.095 inches. 
     
     
         10 . The golf ball of  claim 1 , wherein the thickness of the inner cover layer is about 0.010 to about 0.050 inches. 
     
     
         11 . The golf ball of  claim 1 , wherein the thickness of the outer cover layer is about 0.004 to about 0.020 inches. 
     
     
         12 . The golf ball of  claim 1 , wherein the thickness of the intermediate cover layer is about 0.010 to about 0.040 inches. 
     
     
         13 . The golf ball of  claim 1 , wherein the inner cover layer hardness is greater than the intermediate cover layer hardness by at least 5 Shore D units and the inner cover layer hardness is greater than the outer cover layer hardness by at least 5 Shore D units. 
     
     
         14 . The golf ball of  claim 1 , wherein the inner cover layer hardness is 60 Shore D units or greater. 
     
     
         15 . The golf ball of  claim 1 , wherein the inner cover layer hardness is 68 Shore D units or greater. 
     
     
         16 . The golf ball of  claim 1 , wherein the flex modulus of the inner cover layer is greater than the flex modulus of the intermediate cover layer by at least 5,000 psi and the flex modulus of the inner cover layer is greater than the flex modulus of the outer cover layer by at least 5,000 psi. 
     
     
         17 . A golf ball, comprising:
 a core, and   a multi-layered cover having three layers, the multi-layered cover comprising:
 i) an inner cover layer comprising an ionomer composition containing ethylene acid copolymer having acid groups such that at least 30% of the acid groups are neutralized, the ethylene acid copolymer being present in an amount of at least 10 weight percent; 
 ii) an outer cover layer comprising a first polyurethane composition containing aliphatic polyurethane, the aliphatic polyurethane being present in an amount of at least 10 weight percent; and 
 iii) an intermediate cover layer disposed between the inner cover layer and outer cover layer, the intermediate layer comprising a second polyurethane composition containing an aromatic polyurethane, the aromatic polyurethane being present in an amount of at least 10 weight percent, wherein the total thickness of the multi-layered cover is no greater than 0.110 inches and that the color is visible to a person looking at the exterior of the ball and all of the cover layers are substantially transparent.