Provided are a golf ball which has a surface that sparkles when exposed to ultraviolet rays even if a naturally derived substance is used as a fluorescent material, and it is environmentally and human friendly, and a resin composition for a cover or a topcoat therefor. A resin composition for a cover or a topcoat of a golf ball of the present invention includes: a resin for a cover or a topcoat; and a plant-derived or alga-derived extract which emits light using an absorbed light as an energy source, as a fluorescent material. In the golf ball of the present invention, the cover or the topcoat is formed by using such a resin composition.

Thermoplastic and thermoset compositions including hydroxyurethane linkages, golf ball components formed using such thermoplastic or thermoset compositions, and golf balls including such golf components.

Multi-layered golf balls having at least one layer made of a foamed silicone composition are provided. Multi-layered golf balls having at least one layer made of non-foamed silicone elastomer composition also are provided. For example, three-piece, four-piece, and five-piece golf balls containing different core and cover structures can be made. The foamed silicones have good thermal stability and durability without sacrificing resiliency. The non-foamed silicone elastomers have high elongation, tensile strength, chemical/fluid-resistance, and weatherability properties. These compositions can be used to form any layer, for example, core, intermediate, or cover, in the golf ball.

A polyurethane coating for a golf ball that is based on polyol mixture containing acrylic polyol and BEPD based caprolcatone polyol is disclosed herein. The polyurethane coating comprises a part A component and a part B component, with the part A component comprising an acrylic polyol, a BEPD polyol, a 3-Oxazolidineethanol, a fluorosurfactant, a hindered amine light stabilizer, a UV-absorber, an optical brightener, a dibutyltin dilaurate catalyst, and an organic solvent, and the part B component comprising an aliphatic polyisocyanate and an organic solvent.

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

Disclosed herein are polyurethane/urea golf ball compositions. The compositions comprise the reaction product of a polyisocyanate prepolymer, a reactive ultraviolet light absorber, and a chain extender. Suitable reactive ultraviolet light absorbers contain at least one reactive functional end group.

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

Multi-layered golf balls having at least one layer made from silicone (polysiloxane) elastomers; silicone (polysiloxane) elastomer/polyurethane blends; polycarbonate-polysiloxane blends and copolymers; and polycarbonate-polysiloxane/polyurethane blends are provided. For example, three-piece, four-piece, and five-piece golf balls containing different core and cover structures can be made. The polysiloxane compositions have good thermal stability and durability without sacrificing resiliency. The polysiloxane compositions also have high elongation, tensile strength, chemical/fluid-resistance, and weatherability properties. These compositions can be used to form any layer, for example, core, intermediate, or cover, in the golf ball.

In a golf ball having a core and a cover of one or more layer encasing the core, an outermost layer of the cover is molded of a thermoplastic material selected from the group consisting of polyurethane, polyurea and mixtures thereof, and the surface of the cover is treated with a polyisocyanate compound that is free of organic solvent. A method of manufacturing the golf ball is also described. Such golf balls are endowed with an excellent spin performance and scuff resistance, in addition to which productivity of the golf balls is high.

A golf ball includes a core having an outer surface and a geometric center. The core is formed from a substantially homogenous rubber composition. An ionomeric inner cover layer is formed about the core and has a material hardness of about 60 Shore D or greater. The golf ball includes an outer cover layer formed from a polyurea or a polyurethane and having a material hardness of about 60 Shore D or less. The outer surface of the core has a trans content of about 12% or less and a hardness of about 71 to 88 Shore C. The geometric center of the core has a trans content of about 10% or less and a hardness of about 60 to 80 Shore C. The core has an outer surface hardness greater than a geometric center hardness by about 5 to 19 Shore C to define a positive hardness gradient.