Injection moldable compositions and golf balls prepared therefrom

Abstract

A golf ball is disclosed which includes a Single Component Region which includes greater than 75% by weight of an injection moldable rubber and one or more Discrete Hardness Regions within the Single Component Region. The golf ball may optionally also include a core, an outer cover layer and one or more intermediate layers. Also disclosed are methods of preparing a golf ball including a Single Component Region which includes greater than 75% by weight of an injection moldable rubber and one or more Discrete Hardness Regions within the Single Component Region, whereby the Single Component Region is formed either by sequentially injection molding layers of a polyalkenamer rubber followed by co-curing the resulting structure, or by injection molding one or more pairs of half shells of a polyalkenamer rubber composition, followed by stacking the half shells to form a golf ball precursor structure followed by co-curing the resulting structure.

We claim: 
     
         1 . A golf ball comprising;
 A) a geometric center;   B) an outer surface; and   C) a single component region which spans the distance from the geometric center to the outer surface of the golf ball;   
       wherein said single component region comprises from about 2 to about 10 discrete hardness regions, each discrete hardness region having a thickness of from about 0.01 to about 0.84 inches and wherein said single component region comprises greater than 80% by weight of a polyalkenamer. 
     
     
         2 . The golf ball of  claim 1  wherein said single component region comprises from about 2 to about 8 discrete hardness regions, each discrete hardness region having a thickness of from about 0.015 to about 0.825 inches and wherein said single component region comprises greater than 85% by weight of a polyalkenamer rubber selected from the group consisting of polybutenamer rubber, polypentenamer rubber, polyhexenamer rubber, polyheptenamer rubber, polyoctenamer rubber, polynonenamer rubber, polydecenamer rubber polyundecenamer rubber, polydodecenamer rubber, polytridecenamer rubber and any and all combinations thereof. 
     
     
         3 . The golf ball of  claim 2  wherein said single component region comprises from about 2 to about 5 discrete hardness regions, each discrete hardness region has a thickness of from about 0.02 to about 0.5 inches and wherein said single component region comprises greater than 90% by weight of a polyalkenamer rubber selected from the group consisting of polypentenamer rubber, polyoctenamer rubber, polydodecenamer rubber and any and all combinations thereof. 
     
     
         4 . A golf ball comprising;
 A) a geometric center;   B) an outer cover layer having an inner and outer surface; and   C) a single component region which spans the distance from the geometric center of the ball to the inner surface of the outer cover layer; and   
       wherein said single component region comprises from about 2 to about 10 discrete hardness regions, each discrete hardness region having a thickness of from about 0.01 to about 0.84 inches and wherein said single component region comprises greater than 80% by weight of a polyalkenamer. 
     
     
         5 . The golf ball of  claim 4  wherein said single component region comprises from about 2 to about 8 discrete hardness regions, each discrete hardness region having a thickness of from about 0.015 to about 0.825 inches and wherein said single component region comprises greater than 85% by weight of a polyalkenamer rubber selected from the group consisting of polybutenamer rubber, polypentenamer rubber, polyhexenamer rubber, polyheptenamer rubber, polyoctenamer rubber, polynonenamer rubber, polydecenamer rubber polyundecenamer rubber, polydodecenamer rubber polytridecenamer rubber and any and all combinations thereof. 
     
     
         6 . The golf ball of  claim 5  wherein said single component region comprises from about 2 to about 5 discrete hardness regions, each discrete hardness region having a thickness of from about 0.02 to about 0.5 inches and wherein said single component region comprises greater than 90% by weight of a polyalkenamer rubber selected from the group consisting of polypentenamer rubber, polyoctenamer rubber, polydodecenamer rubber, and any and all combinations thereof. 
     
     
         7 . A golf ball comprising;
 A) a golf ball core having a geometric center and an outer surface;   B) an outer cover layer having an inner and outer surface; and   C) a single component region which spans the distance from the outer surface of said golf ball core to the inner surface of said outer cover layer; and   
       wherein said single component region comprises from about 2 to about 10 discrete hardness regions, each discrete hardness region having a thickness of from about 0.01 to about 0.84 inches and wherein said single component region comprises greater than 80% by weight of a polyalkenamer. 
     
     
         8 . The golf ball of  claim 7  wherein said single component region comprises from about 2 to about 8 discrete hardness regions, each discrete hardness region having a thickness of from about 0.015 to about 0.825 inches and wherein said single component region comprises greater than 85% by weight of a polyalkenamer rubber selected from the group consisting of polybutenamer rubber, polypentenamer rubber, polyhexenamer rubber, polyheptenamer rubber, polyoctenamer rubber, polynonenamer rubber, polydecenamer rubber polyundecenamer rubber, polydodecenamer rubber polytridecenamer rubber and any and all combinations thereof. 
     
     
         9 . The golf ball of  claim 8  wherein said single component region comprises from about 2 to about 5 discrete hardness regions, each discrete hardness region having a thickness of from about 0.02 to about 0.5 inches and wherein said single component region comprises greater than 90% by weight of a polyalkenamer rubber selected from the group consisting of polypentenamer rubber, polyoctenamer rubber, polydodecenamer rubber, and any and all combinations thereof. 
     
     
         10 . The golf ball of  claim 7  wherein the outer cover layer comprises a thermoplastic elastomer, a thermoset polyurethane, a thermoplastic polyurethane, a thermoset polyurea, a thermoplastic polyurea, a unimodal ionomer, a bimodal ionomer, a modified unimodal ionomer, a modified bimodal ionomer; and any and all combinations or mixtures thereof. 
     
     
         11 . The golf ball of  claim 7 , wherein said outer cover layer comprises a blend composition comprising one or more ionomers blended with;
 A) one or more triblock copolymers; or   B) one or more hydrogenation products of the triblock copolymers; or   C) one or more hydrogenated diene block copolymers; and   wherein each triblock copolymer has
 (i) a first polymer block comprising an aromatic vinyl compound, 
 (ii) a second polymer block comprising a conjugated diene compound, and wherein each hydrogenated diene block copolymer has a polystyrene-reduced number-average molecular weight of from 50,000 to 600,000, and is a hydrogenation product of; 
 (i) an A-B block copolymer, in which A is an alkenyl aromatic compound polymer block, and B is either
 (1) a conjugated diene homopolymer block, wherein the vinyl content of the conjugated diene portion is more than 60%, or 
 (2) an alkenyl aromatic compound-conjugated diene random copolymer block wherein the vinyl content of the conjugated diene portion is 15-60%, or 
 
 (ii) an A-B-C block copolymer, in which A and B are as defined above and C is an alkenyl aromatic compound-conjugated diene copolymer tapered block, wherein the proportion of the alkenyl aromatic compound increases gradually, or 
 (iii) an A-B-A block copolymer, in which A and B are as defined above, and wherein in each of the hydrogenated diene block copolymers, the weight proportion of the alkenyl aromatic compound to conjugated diene is from 5/95 to 60/40, the content of the bound alkenyl aromatic compound in at least one block A is at least 3% by weight, the total of the bound alkenyl aromatic compound contents in the two block A's or the block A and the block C is 5% to 25% by weight based on the total monomers, and at least 80% of the double bond unsaturations of the conjugated diene portion is saturated by the hydrogenation. 
   
     
     
         12 . The golf ball of  claim 7 , wherein the outer cover layer comprises the reaction product of:
 A) at least one component A comprising a monomer, oligomer, or prepolymer, or polymer comprising at least 5% by weight of at least one type of functional group;   B) at least one component B comprising a monomer, oligomer, prepolymer, or polymer comprising less by weight of anionic functional groups than the weight percentage of anionic functional groups of the at least one component A; and   C) at least one component C comprising a metal cation,   
       wherein the reaction product comprises a pseudo-crosslinked network of the at least one component A in the presence of the at least one component B. 
     
     
         13 . The golf ball of  claim 7  wherein said one or more intermediate layers comprise a unimodal ionomer, a bimodal ionomer, a modified unimodal ionomer, or a modified bimodal ionomer, and said one or more intermediate layers are disposed;
 1) between said core and said single component region; or 
 2) between said single component region and said outer cover layer; or 
 3) any combination of 1) and 2). 
 
     
     
         14 . A method of preparation of a golf ball comprising a single component region wherein said single component region comprises from about 1 to about 10 discrete hardness regions, each discrete hardness region having a thickness of from about 0.01 to about 0.84 inches and wherein said single component region comprises greater than 80% by weight of a polyalkenamer, the method comprising:
 1) forming a blend of a polyalkenamer rubber and a first crosslinking package;   2) injection molding the blend from step 1 to form an initial layer of the polyalkenamer of a predetermined dimension and,   3) forming a blend of a polyalkenamer rubber and a different crosslinking package from that used in step 1;   4) injection molding the blend from step 3 to form a second layer of the polyalkenamer of a predetermined dimension and,   5) optionally repeating steps 3 and 4 as required;   3) co-curing the structure resulting from steps 1 to 5 to form a single composite region of a crosslinked polyalkenamer composition with discrete hardness regions.   
     
     
         15 . A method of preparation of a golf ball comprising a single component region wherein said single component region comprises from about 1 to about 10 discrete hardness regions, each discrete hardness region having a thickness of from about 0.01 to about 0.84 inches and wherein said single component region comprises greater than 80% by weight of a polyalkenamer, the method comprising:
 1) forming a blend of a polyalkenamer rubber and a first crosslinking package;   2) injection molding the blend from step 1 to form a pair of half shells of a predetermined dimension and,   3) forming a blend of a polyalkenamer rubber and a different crosslinking package from that used in step 1;   4) injection molding the blend from step 3 to form a second pair of half shells of a predetermined dimension and,   5) optionally repeating steps 3 and 4 as required;   6) stacking together the half shells from steps 1) to 5); and   7) co-curing the structure resulting from 1) and 2) to form a single composite region of a crosslinked polyalkenamer composition with discrete hardness regions.   
     
     
         16 . The method of  claim 14  wherein the steps of injections molding comprise maintaining the mold at a temperature such that essentially no crosslinking of the polyalkenamer rubber occurs; and wherein the step of co-curing comprises compression molding the layer resulting from the injection molding at a time, temperature and pressure sufficient to effect the desired degree of crosslinking of the polyalkenamer rubber compositions. 
     
     
         17 . The method of  claim 15  wherein the steps of injections molding comprise maintaining the mold at a temperature such that essentially no crosslinking of the polyalkenamer rubber occurs; and wherein the step of co-curing comprises compression molding the layer resulting from the injection molding at a time, temperature and pressure sufficient to effect the desired degree of crosslinking of the polyalkenamer rubber compositions.