To provide a golf ball that can prevent considerable decrease in carry distance of a driver shot when it rains and also can more reliably prevent adhesion of dirt, etc. to the surface of the golf ball. The golf ball of the present invention includes a core, a cover that is provided on an outer side of the core and has dimples, and an outermost layer that is formed on an outer side of the cover and made of a material having a contact angle of 90 or more and a dynamic contact angle of 85 or less. The golf ball may have a dynamic friction coefficient of 0.48 or less. The cover may be formed of a material having hardness of 48 or more in terms of Shore D Hardness. The outermost layer may be formed of a urethane coating containing a water repellent additive, as a main component.

The present invention provides methods for producing molded golf balls and the resultant balls. The methods of this invention involve producing foamed polyurethane covers and these methods help reduce dimple distortions and other surface imperfections. These golf balls contain an inner core and outer foamed polyurethane cover. One or more intermediate layers can be disposed between the core and cover. In one embodiment, a castable liquid polyurethane composition containing a foaming agent is dispensed into mold cavities, which are then pressed together to form a foam cover for the ball.

A process for making a golf ball includes steps of: a) providing a spherical hollow core which is made from a deformable resilient material, which defines a central chamber, and which includes left and right hemispherical bodies with contiguous circular surfaces having separated upper segments movable away from each other to permit placement of a sensing assembly into the central chamber, b) molding an intermediate shell layer at an elevated temperature that is lower than a softening point of the deformable resilient material to enclose the spherical hollow core, and c) molding a cover to enclose the intermediate shell layer.

The invention provides a golf ball having a core and a cover of one or more layer encasing the core, wherein the core is formed of a rubber composition that includes a base rubber, a co-crosslinking agent and an organic peroxide. The core has a center portion and a surface portion that are unfoamed regions, and has an intermediate portion that contains a foamed region. A method of manufacturing such a golf ball is also provided.

A golf ball is provided that includes at least two layers of material disposed between a spherical core and a cover layer, wherein the elastic modulus of each is within three orders of magnitude of each adjacent layer or core. The spherical core can be a hollow metal core. This results in a golf ball that is legal for play and capable of drive distances essentially equivalent to those of currently available high performance golf balls, but also provides a golf ball that has less hook and slice during play.

A golf ball has a plurality of dimples 12 and a land 14 on a surface thereof. The golf ball further has a large number of minute projections 18 formed on surfaces of the dimples 12 and the land 14. An average pitch Pav of these minute projections 18 is less than 100 m. An average height Hav of these minute projections 18 is not less than 0.5 m and not greater than 50 m. The golf ball satisfies the following mathematical formula.

Lav<3*Tav

In the mathematical formula, Lav represents an average value of distances L between the minute projections 18 and other minute projections 18 adjacent to the minute projections 18, and Tav represents an average value of widths T of these minute projections 18.

A golf ball including a spherical body, first regions, and second regions. The spherical body includes a core layer and a cover layer made from a synthetic resin covering the core layer. Dimples are formed in a surface of the cover layer. First regions that are electrically conductive are formed on a surface of the spherical body. The first regions are formed on a spherical surface having a center of the spherical body as a center. The first regions are positioned at six vertices of an imaginary regular hexahedron such that the vertices are positioned on the surface of the spherical body and, thus, six of the first regions are formed. The second regions are formed in areas of the surface other than where the first regions are formed. The second regions have a radio wave reflectance lower than that of the first regions.

The present invention provides methods for producing molded golf balls and the resultant balls. The methods of this invention involve producing foamed polyurethane covers and these methods help reduce dimple distortions and other surface imperfections. These golf balls contain an inner core and outer foamed polyurethane cover. One or more intermediate layers can be disposed between the core and cover. In one embodiment, a castable liquid polyurethane composition containing a foaming agent is dispensed into mold cavities, which are then pressed together to form a foam cover for the ball.

A golf ball is provided that includes at least two layers of material disposed between a spherical core and a cover layer, wherein the elastic modulus of each is within three orders of magnitude of each adjacent layer or core. The spherical core can be a hollow metal core. This results in a golf ball that is legal for play and capable of drive distances essentially equivalent to those of currently available high performance golf balls, but also provides a golf ball that has less hook and slice during play.

Multi-layered, golf balls having a core made of a foamed composition are provided. The core preferably has a foam inner core (center) and surrounding thermoset or thermoplastic outer core layer. Preferably, a polyurethane foam composition comprising secondary blowing agents that are activated by heat is used to form the foam center. Non-foamed thermoset materials such as polybutadiene rubber may be used to form the outer core layer. The core layers have different hardness gradients and specific gravity values. The foam cores have good resiliency, thermal stability, and durability over a wide temperature range. The ball further includes a cover that may be multi-layered.