abstract |
Multi-layered golf ball core sub-assemblies and the resulting golf balls are provided. The core structure includes an inner core (center) comprising a foam composition, preferably foamed polyurethane. The intermediate and outer core layers are preferably formed from non-foamed thermoset compositions such as polybutadiene rubber. The core layers have different hardness and specific gravity levels. The core assembly preferably has a positive hardness gradient extending across the entire assembly. The core structure and resulting ball have relatively good resiliency. |