Abstract: A golf ball having a cover material made from a polyurea composition is provided. In one version, the golf ball includes a polybutadiene core and surrounding cover layer made of a polyurea composition. In another version, the golf ball includes a polybutadiene core, an intermediate casing layer made of ionomer resin, and an outer cover layer made of the polyurea composition. The polyurea composition is the reaction product of an isocyanate, amine-terminated polycaprolactone, and amine-terminated curing agent. The resulting cover material has many advantageous properties including improved durability, toughness, abrasion-resistance, and moisture-resistance.

Abstract: Golf balls consisting of a multi-layer core and a cover are disclosed. The multi-layer core comprises a thermoset rubber center, a thermoplastic intermediate core layer, and a thermoset rubber outer core layer. At least one of the core layers has a specific gravity of less than 1.05 g/cc and/or at least one of the core layers has a specific gravity of greater than 1.25 g/cc.

Abstract: Golf balls consisting of a multi-layer core and a cover are disclosed. The multi-layer core comprises a thermoset rubber center, a thermoplastic intermediate core layer, and a thermoset rubber outer core layer.

Abstract: A method of making a golf ball comprising the steps of providing an untreated golf ball core comprising a thermoset rubber composition, the untreated golf ball core comprising an untreated outer surface having a hardness; treating the untreated outer surface of the untreated golf ball core with a surface-softening material comprising at least one fatty acid or fatty acid salt composition to form a golf ball core comprising a treated outer surface having a hardness less than the hardness of the untreated outer surface; and forming at least one cover layer about the core to form the golf ball. Also, the untreated core may comprise a geometric center and an untreated outer surface, each having a hardness such that the hardness of the treated outer surface is less than both the hardness of the untreated geometric center and the hardness of the untreated outer surface.