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 5 to 100 parts of an oily substance, by weight per 100 parts of the base rubber. 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 having a diameter of 1.4 inches or less and formed from a rubber composition comprising a base rubber and from 5 to 100 parts of an oily substance, by weight per 100 parts of the base rubber,
a polyurethane or polyurea outer cover layer, and
an intermediate layer disposed between the core and the outer cover layer, the intermediate layer having a thickness of 0.1 inches or greater 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 core has a diameter of from 0.8 inches to 1.4 inches and the intermediate layer has a thickness of from 0.1 inches to 0.3 inches.
3. The solid golf ball of claim 1 , wherein the core has a compression of 50 or less.
4. The solid golf ball of claim 1 , wherein the base rubber is selected from polybutadiene rubber, styrene-butadiene rubber, and combinations of two or more thereof.
5. The solid golf ball of claim 1 , wherein the rubber composition comprises from 20 to 90 parts of the oily substance, by weight per 100 parts of the base rubber.
6. The solid golf ball of claim 1 , wherein the oily substance is paraffinic oil.
7. The solid golf ball of claim 1 , wherein the rubber composition comprises 2.2 parts or greater of a cis-to-trans catalyst, by weight per 100 parts of the base rubber.
8. The solid golf ball of claim 1 , wherein the golf ball has a COR of 0.790 or greater.
9. A solid golf ball comprising:
an inner core layer formed from a rubber composition comprising a base rubber and from 5 to 100 parts of an oily substance, by weight per 100 parts of the base rubber, and having a diameter of 1 inch,
an outer core layer formed from a rubber composition comprising a base rubber and 5 or less parts of an oily substance, by weight per 100 parts of the base rubber, and having a thickness of 0.28 inches,
an inner cover layer formed from a composition comprising an ionomer and having a thickness of 0.03 inches, and
an outer cover layer formed from a composition comprising a castable polyurethane or polyurea and having a thickness of 0.03 inches.