Multi-piece golf balls having a solid core made of a foamed composition and a cover are provided. Preferably, the core is dual-layered having has a foam inner core (center) and surrounding thermoset or thermoplastic outer core layer. Preferably, a polyurethane foam composition containing mineral filler particulate, for example, nanoclay particles, is used to form the foam center. The concentration of clay particulate is preferably in a range of 0.1 to 60% by weight. The surrounding outer core layer may be made from non-foamed or foamed compositions. For example, polybutadiene rubber or highly neutralized olefin acid copolymers may be used in the outer core layer. The core layers have different hardness gradients and specific gravity values.

A golf ball comprising a core and a cover layer, wherein at least one of the core or cover layer comprises a plasticized polyurethane composition comprising at least one polyurethane and at least one plasticizer.

Multi-layered golf balls having a core, intermediate layer, and cover are provided. The ball includes a non-foamed inner core (center) made of a thermoplastic or thermoset composition such as polybutadiene rubber. An intermediate layer comprising a foamed composition, such as polyurethane foam, is disposed about the inner core. The foamed intermediate layer may have a specific gravity gradient within the layer, wherein the outer surface specific gravity is greater than the midpoint specific gravity. Ball constructions having two intermediate layers, wherein at least one layer is a foamed layer can be made. A cover having at least one layer is disposed about the intermediate layer.

Multi-piece golf balls having a multi-layered solid core and multi-layered cover are provided.

A golf ball includes a spherical core and a cover positioned outside the core. The core has an inner layer and an outer layer positioned outside the inner layer. The inner layer is obtained by crosslinking a rubber composition. The rubber composition of the inner layer includes a butyl-based rubber as a base rubber. The inner layer has a diameter Di of not less than 10 mm and not greater than 34 mm. A difference (H2H0) between a Shore C hardness H2 at a surface of the outer layer and a Shore C hardness H0 at a central point of the inner layer is less than 35. Preferably, the butyl-based rubber is a polymer including an isobutylene unit and an isoprene unit, and a derivative thereof.

Multi-layered golf balls containing a dual-core structure are provided. The core structure includes an inner core (center) made from a foam or metal-containing composition, or it has a hollow shell construction, and the outer core layer is made of a thermoplastic composition. Preferably, the thermoplastic composition comprises: a) ethylene acid copolymer, b) plasticizer, and c) cation source. A fatty acid ester such as ethyl oleate is preferably used as the plasticizer. The core assembly preferably has a positive hardness gradient extending across the entire assembly. The core structure and resulting ball have relatively good resiliency at given compressions.

In a multi-piece solid golf ball having a core, a cover and an intermediate layer therebetween, the core, an intermediate layer-encased sphere and the ball have surface hardnesses which satisfy a specific relationship, and the intermediate layer and the cover have thicknesses which satisfy a specific relationship. Also, the core has a hardness profile in which the hardnesses at the core surface, core center, a position 5 mm from the core center, and a position midway between the surface and center of the core satisfy specific relationships. This golf ball, when used by mid- and high-level amateurs, enables the golfer to maintain an adequate distance on shots with a driver and achieve a good distance on iron shots, has a good spin performance on approach shots and has a good feel on impact. In addition, the ball has an excellent scuff resistance when struck with a grooved wedge.

Golf balls comprising a core having at least one layer and a cover having at least one layer are provided. At least one of the layers is made from a thermoplastic composition preferably comprising a telechelic ionomer derived from alkyl-cis-cyclooctene and cis-cyclooctene. The telechelic ionomer composition also may be used to form intermediate layers. Blends of telechelic ionomers and polybutadiene rubbers or ethylene acid copolymers can be prepared. The telechelic ionomer compositions can be used to make a cover layer having good impact durability and shear resistance and that also helps provide the ball with high resiliency.

The present invention provides a golf ball comprising an inner core and an outer cover layer, wherein at least one of the inner core and outer cover layer is formed from a thermoplastic polyurethane ionomer.

Multi-piece golf balls containing a dual-layered core and dual-layered cover are provided. The core structure includes a small, heavy inner core (center) having a relatively high specific gravity, and a surrounding outer core layer. The core layers may have different hardness gradients. The center of the core comprises a metal material such as copper, steel, brass, tungsten, titanium, aluminum, and combinations and alloys thereof preferably dispersed in a thermoplastic polymeric matrix. The outer core layer is preferably formed from a thermoset composition such as polybutadiene. The multi-layered cores and covers have selective specific gravity relationships between the different layers. This helps provide the ball with good flight distance and spin control. The resulting balls have good resiliency and other playing performance properties.