Multi-layer golf ball
Multi-layer golf balls comprising a single- or dual-layer core, an intermediate layer, and an outer cover layer are disclosed. The intermediate layer is formed from a thermoplastic elastomer composition and has a surface hardness which is greater than the center hardness of the core and less than the outer surface hardness of the core. The outer surface hardness of the outer cover layer is greater than the outer surface hardness of the core.
1. A golf ball having a compression of from 30 to 90 and comprising:
a center having a diameter of from 1.25 inches to 1.40 inches, a center Shore C hardness (H center ) of from 45 to 60, an outer surface Shore C hardness (H core surface ) of from 80 to 95, and formed from a rubber composition;
an intermediate layer having an outer surface Shore C hardness (H intermediate surface ) of from 55 to 80, a thickness of from 0.020 inches to 0.120 inches, and formed from a polyester elastomer composition having a material hardness of from 50 Shore C to 80 Shore C and comprising a polyester elastomer and an additional polymer selected from the group consisting of polyolefins, polyamides, polyesters, polyethers, polyurethanes, metallocene-catalyzed polymers, single-site catalyst polymerized polymers, ethylene propylene rubber, ethylene propylene diene rubber, styrenic block copolymer rubbers, alkyl acrylate rubbers, chlorinated polyethylene, polyvinyl chloride, chlorinated polyvinyl chloride, and functionalized derivatives thereof, wherein the polyester elastomer is present in an amount of from 20 wt % to 90 wt % and the additional polymer is present in an amount of from 10 wt % to 80 wt %, based on the combined weight of the polyester elastomer and the additional polymer; and
an outer cover layer having an outer surface Shore C hardness (H outer cover surface ) of from 82 to 99 and a thickness of from 0.020 inches to 0.080 inches;
wherein H center <H intermediate surface <H core surface <H outer cover surface ;
wherein the difference between H core surface and H intermediate surface is from 5 to 30; and
wherein the difference between H center and H core surface is 35 or greater.
2. The golf ball of claim 1 , wherein the additional polymer of the polyester elastomer composition of the intermediate layer is a maleic anhydride-modified polyolefin.
3. The golf ball of claim 1 , wherein the compression of the golf ball is from 40 to 80.
4. The golf ball of claim 1 , wherein the compression of the golf ball is from 50 to 75.
5. The golf ball of claim 1 , wherein the polyester elastomer composition of the intermediate layer has a solid sphere compression of from −50 to 50.
6. The golf ball of claim 1 , wherein the ratio of the overall ball compression to the solid sphere compression of the polyester elastomer composition of the intermediate layer is <1.00.
7. The golf ball of claim 1 , wherein the outer cover layer is formed from a composition selected from ionomers, polyurethanes, polyureas, and blends thereof.
8. The golf ball of claim 7 , wherein the outer cover layer composition has a solid sphere compression of from 80 to 180.
9. The golf ball of claim 1 , wherein the intermediate layer has a thickness of from 0.030 inches to 0.060 inches.
10. The golf ball of claim 1 , wherein the difference between H core surface and H intermediate surface is from 10 to 25.
11. A golf ball having a compression of from 30 to 90 and comprising:
a dual core having an outer diameter of from 1.25 inches to 1.40 inches, a center Shore C hardness (H center ) of from 45 to 60, an outer surface Shore C hardness (H core surface ) of from 80 to 95, and consisting of a center formed from a first rubber composition and an outer core layer formed from a second rubber composition;
an intermediate layer having an outer surface Shore C hardness (H intermediate surface ) of from 55 to 80, a thickness of from 0.020 inches to 0.120 inches, and formed from a polyester elastomer composition having a material hardness of from 50 Shore C to 80 Shore C and comprising a polyester elastomer and an additional polymer selected from the group consisting of polyolefins, polyamides, polyesters, polyethers, polyurethanes, metallocene-catalyzed polymers, single-site catalyst polymerized polymers, ethylene propylene rubber, ethylene propylene diene rubber, styrenic block copolymer rubbers, alkyl acrylate rubbers, chlorinated polyethylene, polyvinyl chloride, chlorinated polyvinyl chloride, and functionalized derivatives thereof, wherein the polyester elastomer is present in an amount of from 20 wt % to 90 wt % and the additional polymer is present in an amount of from 10 wt % to 80 wt %, based on the combined weight of the polyester elastomer and the additional polymer; and
an outer cover layer having an outer surface Shore C hardness (H outer cover surface ) of from 82 to 99 and a thickness of from 0.020 inches to 0.080 inches;
wherein H center <H intermediate surface <H core surface <H outer cover surface ;
wherein the difference between H core surface and H intermediate surface is from 5 to 30; and
wherein the difference between H center and H core surface is 35 or greater.
12. The golf ball of claim 11 , wherein the additional polymer of the polyester elastomer composition of the intermediate layer is a maleic anhydride-modified polyolefin.
13. The golf ball of claim 11 , wherein the compression of the golf ball is from 40 to 80.
14. The golf ball of claim 11 , wherein the compression of the golf ball is from 50 to 75.
15. The golf ball of claim 11 , wherein the polyester elastomer composition of the intermediate layer has a solid sphere compression of from −50 to 50.
16. The golf ball of claim 11 , wherein the ratio of the overall ball compression to the solid sphere compression of the polyester elastomer composition of the intermediate layer is <1.00.
17. The golf ball of claim 11 , wherein the outer cover layer is formed from a composition selected from ionomers, polyurethanes, polyureas, and blends thereof.
18. The golf ball of claim 17 , wherein the outer cover layer composition has a solid sphere compression of from 80 to 180.
19. The golf ball of claim 11 , wherein the intermediate layer has a thickness of from 0.030 inches to 0.060 inches.
20. The golf ball of claim 11 , wherein the difference between H core surface and H intermediate surface is from 10 to 25.