US Patent 7,452,291
Foam-core golf balls
Abstract
A golf ball with a controlled moment of inertia and controlled spin rate is disclosed. The increase in moment of inertia is preferably accomplished by a reduction in the specific gravity or weight of the core, e.g., by foaming. Preferably, this reduction is less than about 15% in specific gravity or less than about 25% in weight to minimize the reduction in the coefficient of restitution of the core.