Patent ID: 7429221
Filing Date: 2008-09-30
Classification: A63B

Abstract:
1. A golf ball comprising: an inner core comprising a metal salt of a carboxylic acid in an amount of about 15 phr to about 30 phr, the inner core having a first outer surface and a geometric center and being formed from a first substantially homogenous formulation throughout such that the inner core has a hardness of 35 Shore C to 85 Shore C; an outer core layer comprising a metal salt of a carboxylic acid in an amount of about 30 phr to about 45 phr and has a ratio of antioxidant to initiator of about 0.50 or greater when normalized to 100% activity, the outer core being disposed about the inner core having a second outer surface and an inner surface and being formed from a second substantially homogenous formulation throughout such that the outer core layer has a hardness of 55 Shore C to 90 Shore C; and a cover layer disposed about the outer core layer; wherein the geometric center, the first and second outer surfaces, and the inner surface each have a hardness, the hardness of the first outer surface being greater than the hardness of the geometric center to define a positive hardness gradient, and the hardness of the second outer surface being substantially the same as or lower than the hardness of the inner surface to define a negative hardness gradient; and wherein the initiator is present in the amount from about 0.25 phr to about 5.0 phr at 100% activity and the antioxidant is present in amount of about 0.2 phr to about 1 phr.