Golf balls having multi-layered cores with thermoset outer layer

摘要

Multi-piece golf balls containing a multi-layered core structure are provided. The core structure includes a small, heavy inner core (center) having a relatively high specific gravity, an intermediate core layer, and a surrounding outer core layer. The layers of the core structure may have different hardness gradients. The center of the core comprises a metal material such as copper, steel, brass, tungsten, titanium, aluminum, and alloys thereof. The intermediate core layer is preferably formed from a first thermoset composition such as polybutadiene rubber, and the outer core layer is preferably formed from a second thermoset composition. The resulting ball has high resiliency and good spin control.

主权项

1. A golf ball, comprising:
a multi-layered core including i) an inner core comprising a metal material, the inner core having a diameter in the range of about 0.100 to about 1.100 inches, a specific gravity (SGinner), and an outer surface hardness (Hcenter surface) and a center hardness (Hcenter material), the Hcenter surface being greater than the Hcenter material to provide a positive hardness gradient; ii) an intermediate core layer comprising a thermoset material the intermediate layer being disposed about the inner core and having a thickness in the range of about 0.050 to about 0.400 inches, and an outer surface hardness (Houter surface of IC) and an inner surface hardness (Hinner surface of IC), the Hcenter surface of IC being greater than the Hinner surface of IC to provide a positive hardness gradient; and iii) an outer core layer comprising a thermoset material, the outer core layer being disposed about the intermediate core layer and having a thickness in the range of about 0.200 to about 0.750 inches, a specific gravity (SGouter), and an outer surface hardness ((Houter surface of OC) of 40 to 85 Shore C and an inner surface hardness (Hinner surface of OC) of 42 to 87 Shore C, the Houter surface of OC being the same or less than the Hinner surface of OC to provide a zero or negative hardness gradient, wherein the SGinner is greater than de SGouter and the volume of the outer core layer is greater than the volume of each of the inner core and intermediate core layers; and a cover having at least one layer disposed about the multi-layered core.