Multi-layer core golf ball
View Patent ↗Golf balls comprising a multi-layer core and a cover are disclosed. The multi-layer core comprises a layer formed from a highly neutralized polymer composition, a layer formed from an additional thermoplastic composition, and an outermost layer formed from a thermoset rubber.
1. A golf ball comprising:
an inner core layer formed from a highly neutralized polymer composition and having a diameter of from 1.000 inches to 1.580 inches;
an intermediate core layer formed from a thermoplastic composition selected from the group consisting of partially- and fully-neutralized ionomers optionally blended with a maleic anhydride-grafted non-ionomeric polymer, polyesters, polyethers, polyamides, and blends of two or more thereof, and having a thickness of from 0.005 inches to 0.100 inches and a surface hardness of 85 Shore C or greater;
an outer core layer formed from a thermoset rubber composition and having a thickness of from 0.010 inches to 0.100 inches and a surface hardness of 50 Shore C or greater; and
a cover layer having a thickness of from 0.010 inches to 0.050 inches and a surface hardness of 65 Shore D or less.
2. The golf ball of claim 1 , wherein the intermediate core layer has a surface hardness of 90 Shore C or greater.
3. The golf ball of claim 1 , wherein the intermediate core layer has a surface hardness of 93 Shore C or greater.
4. The golf ball of claim 1 , wherein the inner core layer has a surface hardness of from 50 Shore C to 85 Shore C and a zero hardness gradient.
5. A golf ball consisting essentially of:
an inner core layer formed from a highly neutralized polymer composition and having a diameter of from 1.000 inches to 1.580 inches;
an intermediate core layer formed from a thermoplastic composition selected from the group consisting of partially- and fully-neutralized ionomers optionally blended with a maleic anhydride-grafted non-ionomeric polymer, polyesters, polyethers, polyamides, and blends of two or more thereof, and having a thickness of from 0.005 inches to 0.100 inches and a surface hardness of 85 Shore C or greater;
an outer core layer formed from a diene rubber composition and having a thickness of 0.010 inches to 0.100 inches and a surface hardness of 50 Shore C or greater; and
a cover layer formed from a polyurethane, a polyurea, or a copolymer or blend thereof, and having a thickness of from 0.010 inches to 0.050 inches and a surface hardness of 65 Shore D or less.
6. The golf ball of claim 5 , wherein the intermediate core layer has a surface hardness of 90 Shore C or greater.
7. The golf ball of claim 5 , wherein the intermediate core layer has a surface hardness of 93 Shore C or greater.
8. The golf ball of claim 5 , wherein the inner core layer has a surface hardness of from 50 Shore C to 85 Shore C and a zero hardness gradient.
9. The golf ball of claim 1 , wherein the outer core layer has a surface hardness of from 50 Shore C to 80 Shore C.
10. The golf ball of claim 5 , wherein the outer core layer has a surface hardness of from 50 Shore C to 80 Shore C.