Rubber compositions comprising high levels of oily substance and the use thereof in golf balls
The present invention is directed to golf balls having at least one layer formed from a rubber composition comprising a base rubber and from 10 parts to 120 parts of an oily substance, by weight per 100 parts of the base rubber. The base rubber is a polybutadiene having a Mooney viscosity of 40 or greater. The rubber composition may be present in any one or more of a core layer, a cover layer, or an intermediate layer.
1. A solid golf ball comprising:
a core formed from a rubber composition comprising a base rubber and from 10 parts to 120 parts of an oily substance, by weight per 100 parts of the base rubber, wherein the base rubber is a polybutadiene having a Mooney viscosity of 55 or greater,
a polyurethane or polyurea outer cover layer, and
an intermediate layer disposed between the core and the outer cover layer and formed from a highly resilient material selected from partially- and fully-neutralized acid copolymers and blends thereof.
2. The solid golf ball of claim 1 , wherein the polybutadiene has a Mooney viscosity of 65 or greater.
3. The solid golf ball of claim 1 , wherein the polybutadiene has a Mooney viscosity of 75 or greater.
4. The solid golf ball of claim 1 , wherein the polybutadiene is neodymium-catalyzed polybutadiene.
5. The solid golf ball of claim 4 , wherein the polybutadiene rubber has a cis content of 90% or greater.
6. The solid golf ball of claim 1 , wherein the oily substance is a low PCA oil.
7. The solid golf ball of claim 1 , wherein the rubber composition comprises at least 30 parts of the oily substance, by weight per 100 parts of the base rubber.
8. The solid golf ball of claim 1 , wherein the core has a compression of 50 or less.
9. The solid golf ball of claim 1 , wherein the intermediate layer has a thickness of 0.1 inches or greater.
10. A solid golf ball comprising:
a core having a diameter of from 0.8 inches to 1.4 inches and formed from a rubber composition comprising a base rubber and from 30 parts to 120 parts of an oily substance, by weight per 100 parts of the base rubber, wherein the base rubber is a neodymium-catalyzed polybutadiene having a Mooney viscosity of 65 or greater and a cis content of 90% or greater,
a polyurethane or polyurea outer cover layer, and
an intermediate layer disposed between the core and the outer cover layer, wherein the intermediate layer has a thickness of 0.1 inches or greater and is formed from a highly resilient material selected from partially- and fully-neutralized acid copolymers and blends thereof.