Golf balls comprising medium hardness gradient core
A golf ball includes a core having an outer surface and a geometric center. The core is formed from a substantially homogenous rubber composition. An ionomeric inner cover layer is formed about the core and has a material hardness of about 60 Shore D or greater. The golf ball includes an outer cover layer formed from a polyurea or a polyurethane and having a material hardness of about 60 Shore D or less. The outer surface of the core has a trans content of about 12% or less and a hardness of about 71 to 88 Shore C. The geometric center of the core has a trans content of about 10% or less and a hardness of about 60 to 80 Shore C. The core has an outer surface hardness greater than a geometric center hardness by about 5 to 19 Shore C to define a positive hardness gradient.
1. A golf ball comprising:
a core having an outer surface and a geometric center and being formed from a substantially homogenous rubber composition;
an inner cover layer, the inner cover layer comprising an ionomeric material and having a material hardness of about 60 Shore D or greater; and
an outer cover layer, the outer cover layer comprising a polyurea or a polyurethane and having a material hardness of about 60 Shore D or less;
wherein the outer surface has a trans content of about 12% or less and a hardness of about 71 Shore C to 88 Shore C, the geometric center has a trans content of about 10% or less and a hardness of about 60 to 80 Shore C, and the outer surface hardness is greater than the geometric center hardness by about 5 to 19 Shore C to define a positive hardness gradient.
2. The golf ball of claim 1 , wherein the positive hardness gradient is about 10 to 19 Shore C.
3. The golf ball of claim 2 , wherein the positive hardness gradient is about 12 to 19 Shore C.
4. The golf ball of claim 1 , wherein the core has an outer diameter of about 1.45 to about 1.62 inches.
5. The golf ball of claim 4 , wherein the core has an outer diameter of about 1.50 to about 1.58 inches.
6. The golf ball of claim 1 , wherein the hardness of the core geometric center is about 60 to 70 Shore C.
7. The golf ball of claim 1 , wherein the hardness of the core surface is about 74 to 85 Shore C.
8. The golf ball of claim 7 , wherein the core surface hardness is about 80 to 84 Shore C.
9. The golf ball of claim 7 , wherein the core surface hardness is about 75 to 79 Shore C.
10. The golf ball of claim 1 , wherein the outer surface has a trans content of about 10% or less and the geometric center has a trans content of about 8% or less.
11. A golf ball comprising:
a core having an outer surface and a geometric center and being formed from a substantially homogenous rubber composition;
an inner cover layer, the inner cover layer comprising an ionomeric material and having a material hardness of about 60 Shore D or greater; and
an outer cover layer, the outer cover layer comprising a polyurea or a polyurethane and having a material hardness of about 60 Shore D or less;
wherein the outer surface has a trans content of about 12% or less and a hardness of about 45 to 56 Shore D, the geometric center has a trans content of about 10% or less and a hardness of about 35 to 45 Shore D, and the outer surface hardness is greater than the geometric center hardness by about 3 to 15 Shore D to define a positive hardness gradient.
12. The golf ball of claim 11 , wherein the geometric center has a hardness of about 38 to 43 Shore D.
13. The golf ball of claim 11 , wherein the outer surface hardness is about 48 to 54 Shore D.
14. The golf ball of claim 1 , wherein the positive hardness gradient is about 5 to 13 Shore D.
15. The golf ball of claim 14 , wherein the positive hardness gradient is about 7 to 11 Shore D.
16. A golf ball comprising:
a core having an outer surface and a geometric center and being formed from a substantially homogenous rubber composition;
an inner cover layer, the inner cover layer comprising an ionomeric material and having a material hardness of about 60 Shore D or greater; and
an outer cover layer, the outer cover layer comprising a polyurea or a polyurethane and having a material hardness of about 60 Shore D or less;
wherein the outer surface has a trans content of about 12% or less and a hardness of about 71 Shore C to 88 Shore C, the geometric center has a trans content of about 10% or less and a hardness of about 60 to 80 Shore C, and the outer surface hardness is greater than the geometric center hardness by about 12 to 19 Shore C to define a positive hardness gradient.