Golf ball compositions
View Patent ↗Golf balls comprising a core and a cover are disclosed. The core is a dual- or multi-layer core, wherein at least one layer is formed from a rubber composition comprising a base rubber and a catechol. The core layer formed from such rubber composition has a positive hardness gradient such that the difference between the layer's outer surface hardness and inner surface hardness is 5 Shore C units or greater.
1. A golf ball comprising:
a core comprising an inner core layer and an outer core layer; and
a cover comprising an inner cover layer and an outer cover layer;
wherein the inner core layer is formed from a rubber composition comprising a base rubber and a catechol; and
wherein the inner core layer has a positive hardness gradient wherein the difference between the Shore C hardness of the outer surface of the inner core layer (H INNER CORE OUTER SURFACE ) and the Shore C hardness of the center of the inner core layer (H CENTER )≧5 Shore C units; and
wherein the surface hardness of the outer core layer is greater than the material hardness of the inner cover layer.
2. The golf ball of claim 1 , wherein H INNER CORE OUTER SURFACE −H CENTER ≧10 Shore C units.
3. The golf ball of claim 1 , wherein H INNER CORE OUTER SURFACE −H CENTER ≧15 Shore C units.
4. The golf ball of claim 1 , wherein H INNER CORE OUTER SURFACE −H CENTER ≧20 Shore C units.
5. The golf ball of claim 1 , wherein H INNER CORE OUTER SURFACE −H CENTER ≧25 Shore C units.
6. The golf ball of claim 1 , wherein the core comprises an additional outer core layer.
7. A golf ball comprising:
a core consisting of an inner core layer and an outer core layer; and
a cover comprising an inner cover layer and an outer cover layer;
wherein the outer core layer is formed from a rubber composition comprising a base rubber and a catechol; and
wherein the outer core layer has a positive hardness gradient wherein the difference between the Shore C hardness of the outer surface of the outer core layer (H OUTER SURFACE ) and the Shore C hardness of the inner surface of the outer core layer (H OUTER CORE INNER SURFACE )≧5 Shore C units; and
wherein the surface hardness of the outer core layer is greater than the material hardness of the inner cover layer.
8. The golf ball of claim 7 , wherein H OUTER SURFACE −H OUTER CORE INNER SURFACE ≧10 Shore C units
9. The golf ball of claim 7 , wherein H OUTER SURFACE −H OUTER CORE INNER SURFACE ≧15 Shore C units.
10. The golf ball of claim 7 , wherein H OUTER SURFACE −H OUTER CORE INNER SURFACE ≧20 Shore C units.
11. A golf ball comprising:
a core comprising an inner core layer, a first outer core layer, and a second outer core layer; and
a cover comprising an inner cover layer and an outer cover layer;
wherein at least one of the first and second outer core layers is formed from a rubber composition comprising a base rubber and a catechol; and
wherein the outer core layer formed from the rubber composition comprising the catechol has a positive hardness gradient wherein the difference between the Shore C hardness of the outer surface of the outer core layer (H OUTER SURFACE ) and the Shore C hardness of the inner surface of the outer core layer (H OUTER CORE INNER SURFACE ) ≧5 Shore C units; and
wherein the surface hardness of the second outer core layer is greater than the material hardness of the inner cover layer.
12. The golf ball of claim 11 , wherein H OUTER SURFACE −H OUTER CORE INNER SURFACE ≧10 Shore C units
13. The golf ball of claim 11 , wherein H OUTER SURFACE −H OUTER CORE INNER SURFACE ≧15 Shore C units.
14. The golf ball of claim 11 , wherein H OUTER SURFACE −H OUTER CORE INNER SURFACE ≧20 Shore C units.