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.

A golf ball 2 includes a core 4 and a cover 6 positioned outside the core 4. The cover 6 is formed in a mold having support pins by injection molding. A ratio (V/S) of a volume V (mm.sup.3) of the cover 6 to an amount of compressive deformation S (mm) of the core 4 is not less than 1000 and not greater than 1900. The cover 6 has a shore D hardness of not greater than 62. The golf ball 2 has a plurality of dimples 8 on a surface thereof. A total volume W of these dimples is not less than 490 mm.sup.3 and not greater than 620 mm.sup.3. A ratio (/P) of a latitude (degree) of each support pin to a total cross-sectional area P (mm.sup.2) of the support pins is not less than 0.35 and not greater than 0.60.

A golf ball with a coating disposed on a cover that is infused with graphene in an amount ranging from 0.01% to 5% based on a dry weight of the paint film is disclosed herein. The coating is preferably based on polyurethane chemistry where hydroxyl functional polymers are cured with polyisocyanate-based hardeners. The coating is preferably applied in a dipping process or a spraying process.

A golf ball includes a center, a mid layer, a cover and dimples. The cover has a Shore D hardness of 30-50. The golf ball has an amount of compressive deformation of 3.0-5.0 mm. The ball meets a mathematical formula (I):

0.80((L1+L2)/2)0.95(I).

L1 represents a ratio of a lift coefficient relative to a drag coefficient, the lift coefficient and the drag coefficient being measured under conditions of a Reynolds number of 1.29010.sup.5 and a spin rate of 2820 rpm. L2 represents a ratio of a lift coefficient relative to a drag coefficient, the lift coefficient and the drag coefficient being measured under conditions of a Reynolds number of 1.77110.sup.5 and a spin rate of 2940 rpm.

A golf ball for amateur golfers exhibits excellent flight characteristics when hit by the average golfer and also has a good feel at impact that is both soft and solid. The golf ball includes a core, an intermediate layer and a cover, and has coefficient of restitution and compressive deformation relationships that satisfy specific conditions.

An object of the present invention is to provide a golf ball traveling a great flight distance and having a good shot feeling on long iron shots. The present invention provides a golf ball comprising a core, at least one intermediate layer covering the core and a cover covering the intermediate layer, wherein the core is formed from a core rubber composition containing (a) a base rubber containing a polybutadiene, (b) an ,-unsaturated carboxylic acid having 3 to 8 carbon atoms and/or a metal salt thereof as a co-crosslinking agent, (c) a crosslinking initiator, and (d) a terpene-based resin, and a material hardness (Hm) of the intermediate layer is higher than a material hardness (Hc) of the cover, and the material hardness (Hc) of the cover is less than 50 in Shore D hardness.

Low compression, multi-piece golf balls containing a solid core and two or three-layered cover assemblies are provided. Preferably, the ball has a compression of less than 60 and more preferably less than 50. At least one cover layer is made of a plasticized thermoplastic composition. For example, two-layered and three-layered covers may be made. Preferably, the plasticized thermoplastic composition comprises: a) ethylene acid copolymer, b) plasticizer, and c) cation source. A fatty acid ester such as ethyl oleate or butyl oleate is preferably used as the plasticizer. The cover assembly has good impact durability and helps provide the ball with relatively high resiliency at given compressions.

A golf ball resin composition includes (a) an olefin-,-unsaturated carboxylic acid copolymer and/or a metal ion neutralization product thereof or an olefin-,-unsaturated carboxylic acid-,-unsaturated carboxylic acid ester copolymer and/or a metal ion neutralization product thereof, (b) a phenolic resin and (c) a compound having at least two oxazoline groups per molecule, wherein the content of component (C) is from 0.1 to 5 parts by weight per 100 parts by weight of components (a) and (b) combined. The resin composition has excellent tensile properties and, when used in a golf ball, provides the ball with an excellent durability without lowering the spin performance and distance performance of the ball. The resin is especially useful as a golf ball cover material for an outermost layer or an intermediate layer.

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 borophene material. Mixtures of borophene material and polybutadiene rubbers or ethylene acid copolymers can be prepared. The borophene-containing compositions can be used to make a core layer having good strength and impact durability and it also should help provide the ball with high resiliency.

A golf ball for amateur golfers is endowed with an excellent flight when hit by the average golfer whose head speed is not that high and also has a good feel at impact that is soft and solid on full shots with all golf club numbers. The golf ball, which includes a core and a cover, has a compressive deformation A under 0.2 kgf to 5 kgf loading that is 0.21 mm or less and a compressive deformation B under 5 kgf to 30 kgf loading that is from 0.73 to 0.95 mm. Also, letting D be the compressive deformation of the ball under 10 kgf to 130 kgf loading and C be the compressive deformation of the ball under 5 kgf to 60 kgf loading, the ratio D/A is from 16.0 to 20.5 and the ratio D/C is from 1.80 to 1.90.