Compositions for use in golf balls

A golf ball, comprising:

• a core, the core having a first diameter of 1.64 inches or less, a first compression of 100 or less, a first coefficient of restitution of 0.78 or greater, a first deflection at 100 kg force of 1.5 mm or greater, a specific gravity of 1.4 g/cm3 or greater, and a center hardness that is less than a surface hardness by 3 Shore C points or more, wherein the core comprises a rubber having a Mooney viscosity of 30 or greater, a crosslinking agent at a level of 10 phr or more by weight of the rubber, a regrind and/or filler, and optionally a compound that enhances the first coefficient of restitution;
• and
• a cover layer disposed about the core, the cover layer having a material hardness of 25 Shore D to 65 Shore D, a flexural modulus of 2,000 psi or greater, comprising a prepolymer of a saturated polyisocyanate and a hydrogenated polybutadiene polyol having a number average molecular weight of 2,000 to 5,000 and a hydroxyl functionality of 1.9, cured with a saturated secondary polyamine,
• and wherein the golf ball has a second diameter of 1.68 inches or greater, a second compression of 110 or less, a second coefficient of restitution of 0.79 or greater, a second deflection at 100 kg force of 1.0 mm or greater, a moment of inertia of 87 or less, and a dimple pattern having 250 to 450 dimples.

A golf ball, comprising:

• a core, the core having a first diameter of 1.64 inches or less, a first compression of 100 or less, a first coefficient of restitution of 0.78 or greater, a first deflection at 100 kg force of 1.5 mm or greater, a surface hardness of 60 Shore C or greater, wherein the core comprises:
• a center having a second diameter of 0.375 inches to 1.6 inches, a second compression of 10 to 60, and a second deflection at 100 kg force of 1.0 mm or greater, the center comprising a rubber having a Mooney viscosity of 30 or greater, a crosslinking agent at a level of 10 phr to 40 phr by weight of the rubber, a regrind and/or a filler, and optionally a compound that enhances the first coefficient of restitution, and
• an outer core layer disposed about the center, the outer core layer comprising a rubber having a Mooney viscosity of 30 or greater, a crosslinking agent at a level of 25 phr to 55 phr by weight of the rubber, a regrind and/or a trans polyisoprene, a filler, and optionally a compound that enhances the first coefficient of restitution;
• and
• a cover layer disposed about the core, the cover layer having a material hardness of 25 Shore D to 65 Shore D, a flexural modulus of 2,000 psi or greater, comprising a prepolymer of a saturated polyisocyanate and a hydrogenated polybutadiene polyol having a number average molecular weight of 2,000 to 5,000 and a hydroxyl functionality of 1.9, cured with a saturated secondary polyamine,
• and wherein the golf ball has a second diameter of 1.68 inches or greater, a second compression of 110 or less, a second coefficient of restitution of 0.79 or greater, a second deflection at 100 kg force of 1.0 mm or greater, a moment of inertia of 87 or less, and a dimple pattern having 250 to 450 dimples.