In a golf ball having a core, envelope layer, intermediate layer and cover, the (core diameter)/(ball diameter) value falls within a particular range, the core has a specific hardness profile, the intermediate layer is formed primarily of an ionomer resin material including a high-acid ionomer resin, and the Shore C hardness relationships among the core center and surface hardnesses and the surface hardnesses of the envelope layer-encased sphere, intermediate layer-encased sphere and ball satisfy the following conditions: (1) core surface hardness<surface hardness of envelope layer-encased sphere<surface hardness of intermediate layer-encased sphere>ball surface hardness, (2) (surface hardness of envelope layer-encased sphere)−(core center hardness)≥28. Also, the intermediate layer and cover have respective thicknesses which satisfy the condition: (3) cover thickness<intermediate layer thickness. This ball enables mid-level and skilled amateur golfers to achieve superior distances on driver shots and on iron shots, and moreover has a soil yet good feel at impact.

An object of the present invention is to provide a golf ball showing excellent shot feeling and stain resistance. The present invention provides a golf ball comprising a golf ball body and a paint film formed on a surface of the golf ball body, wherein a base resin constituting the paint film includes a polyurethane obtained by a reaction between a polyol composition and a polyisocyanate composition, a molar ratio (NCO/OH) of an isocyanate group (NCO group) in the polyisocyanate composition to a hydroxyl group (OH group) in the polyol composition is 0.6 or more, and the paint film has an elastic modulus of 300 MPa or less.

Methods for coatings for golf balls, particularly golf balls having thermoplastic polyurethane covers, and the resulting finished balls are provided. The coating is preferably a topcoat comprising a polyurethane composition containing optical brighteners. The topcoat composition preferably comprises a low concentration of optical brighteners. For example, the concentration of optical brightener can be in the range of 0.01 to about 0.20 weight %. The optical brighteners provide the desired brightness to the golf ball without sacrificing color stability. Multi-piece golf balls having inner cores, outer cores, inner covers, and intermediate layers can be made. The finished ball with the topcoat has many advantageous physical and playing performance properties.

Golf balls having covers made of thermoplastic polyurethane compositions are provided. Multi-piece golf balls can be made. In one embodiment, the outer cover layer is formed from a composition comprising a thermoplastic polyurethane and polydimethylsiloxane compound. Functionalized polydimethylsiloxane compounds also can be used to treat thermoplastic polyurethane golf ball covers. The cover composition and surface coatings can further include catalysts, ultraviolet (UV)-light stabilizers, and other additives. The coating methods have many benefits and the finished balls with thermoplastic polyurethane covers have good physical properties.

Golf balls having covers made of thermoplastic polyurethane compositions are provided. Multi-piece golf balls can be made. Polyurethane primer coatings and polyurethane top-coatings are applied to the thermoplastic polyurethane cover. Isocyanate-rich and polyol-rich polyurethane coatings can be applied. In one embodiment, multi-functional imine and amine compounds can be used to treat the golf ball. The resulting coating may contain polyurethanes, polyureas, and hybrids, copolymers, and blends thereof. The cover composition and surface coatings can further include catalysts, ultraviolet (UV)-light stabilizers, and other additives. Heat is used to cure the coatings. The coating methods have many benefits and the finished balls have good physical properties.

Golf ball comprising one or more layers and/or indicia formed from a fluorescent composition comprising: a base polymer; and a colorant; wherein the colorant is a small-molecule ionic isolation lattice formed from one or more fluorescent dye and one or more cyanostar macrocycles. The one or more fluorescent dyes may include at least one dye selected from xanthenes, oxazines, styryls, cyanines, trianguleniums, or mixtures thereof. The colorant may be a dispersion of the small-molecule ionic isolation lattice in a carrier medium or a powder. In particular embodiments, at least one of the one or more layers is a cover layer and/or a coating layer.

An object of the present invention is to provide a golf ball showing both striking a good balance between the visibility and the weather resistance. The present invention provides a golf ball comprising a golf ball body and two or more paint film layers formed on a surface of the golf ball body, wherein the paint film layers comprises a first paint film layer containing an inorganic fluorescent agent but substantially not containing an ultraviolet absorber, and a second paint film layer containing an ultraviolet absorber but substantially not containing an inorganic fluorescent agent; and the second paint film layer is disposed inside the first paint film layer.

The present invention relates to a carboxylic branched chain-cutting agent for a golf ball-covering ionomer resin, a golf ball coating composition, and a method for manufacturing a golf ball. The present invention can provide a coating composition containing within an appropriate range, a specific compound for use as a carboxylic branched chain-cutting agent for a golf ball-covering ionomer resin, and thus can provide a golf ball on which a bridge is formed between a golf ball covering resin and a coating resin. By providing the coating composition containing a specific composition for use as a carboxylic branched chain-cutting agent for a golf ball-covering ionomer resin, the present invention is appropriate for ensuring the physical properties of the golf ball, such as yellowing resistance, and workability, such as pot life, even eliminating an adhesion pretreatment step, thereby reducing side effects due to the existing pretreatment step while providing a golf ball having excellent physical properties.

A golf ball having a single pass image printed on the outer surface having at least one core and a cover layer formed from a cast polyurethane or polyurea. The cover layer defines a first surface area portion of a first color and a second surface area portion of a single pass printed image. The single pass printed image is printed using a UV curable ink and at least one UV pinning operation to pre-cure the UV curable ink before a final UV curing operation.

Golf ball 2 of the present invention has core 4, cover 10 situated on the external side of the core 4, and paint layer 16 provided to cover this cover 10. The base polymer of the cover 10 is a urethane resin. The base polymer of the paint layer 16 is a urethane resin. The cover 10 has a thickness Tc of 0.1 mm or greater and 0.7 mm or less. The paint layer 16 has a thickness Tp (mm) of 0.015 mm or greater and 0.040 mm or less. The ratio (Tp/Tc) is 0.021 or greater and 0.40 or less. Preferably, the paint layer 16 is formed with two or more layers 18 and 20. Preferably, the base polymer of the paint layer 16 is a two-pack type urethane resin or a two-pack type epoxy resin.