An object of the present invention is to provide a golf ball that can strike a good balance in approach performance under a rough condition and a wet condition while maintaining a flight distance on driver shots. 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 the golf ball body has a spherical core, an intermediate layer covering the spherical core, and a cover covering the intermediate layer, and the paint film has a multi-layered construction composed of two or more layers, wherein a 10% elastic modulus (Pi10) of an innermost layer of the paint film is greater than a 10% elastic modulus (Po10) of an outermost layer of the paint film and a 10% elastic modulus (C10) of a material constituting the cover, and a thickness (Ti) of the innermost layer of the paint film is greater than a thickness (To) of the outermost layer of the paint film, a 10% elastic modulus (M10) of a material constituting the intermediate layer is greater than the 10% elastic modulus (C10) of the material constituting the cover, and a difference (Po10C10) between the 10% elastic modulus (Po10) of the outermost layer of the paint film and the 10% elastic modulus (C10) of the material constituting the cover is 4.0 kgf/cm.sup.2 or more and 50 kgf/cm.sup.2 or less, and a Shore D hardness (Hc) of the material constituting the cover is 40 or less.

An object of the present invention is to provide a golf ball showing improved controllability on approach shots for less than 40 yards, in particular, on approach shots around the green (about 10 yards to 20 yards) and improved controllability on approach shots from the rough, and showing excellent shot feeling. The present invention provides a golf ball comprising a golf ball body and a paint film covering the golf ball body, wherein a loss tangent tans has a peak temperature of 50 C. or less and a peak height of less than 0.8, obtained by measuring dynamic viscoelasticity of the paint film under the following conditions:

<Measuring Conditions> Measuring mode: tensile mode Measuring temperature range: from 100 C. to 150 C. Temperature rising rate: 4 C./min Oscillation frequency: 10 Hz Measuring strain: 0.1.

Systems and methods for measuring and classifying golf balls and/or components thereof according to concentricity including automated inspection systems that can simultaneously image multiple golf balls (or components thereof) to gather and analyze data on concentricity and, optionally, classify or sort the multiple golf balls (or components thereof) according to the analyzed concentricity data.

A golf ball according to the present invention comprises: a core having a diameter of 37-39 mm and a first density; a mantle which surrounds the core, includes amorphous alloy powder, and has a thickness of 0.8-1.2 mm and a second density; and a cover which surrounds the mantle and has a thickness of 1-1.4 mm and a third density.

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 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 acid copolymer ionomer. The cover composition also can contain hydroxyl-containing compounds. The golf ball having the thermoplastic polyurethane cover can be treated with an isocyanate compound. The golf ball also can be treated with a hydroxyl and/or silane-containing compound. 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 have good physical properties.

The present invention is directed to golf balls having improved aerodynamic performance due, at least in part, to the selection of the plan shapes of the dimples thereon. In particular, the present invention is directed to a golf ball that includes at least a portion of its dimples having a plan shape defined by low frequency periodic functions along a closed simple path. In addition, the present invention provides methods for designing dimples having a plan shape defined by a low frequency periodic function along a closed simple path.

An object of the present invention is to provide a golf ball that can strike a good balance in approach performance under a rough condition and a wet condition while maintaining a flight distance on driver shots. 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 the golf ball body has a spherical core, an intermediate layer covering the spherical core, and a cover covering the intermediate layer, and the paint film has a multi-layered construction composed of two or more layers, wherein a 10% elastic modulus (Pi10) of an innermost layer of the paint film is greater than a 10% elastic modulus (Po10) of an outermost layer of the paint film and a 10% elastic modulus (C10) of a material constituting the cover, and a thickness (Ti) of the innermost layer of the paint film is greater than a thickness (To) of the outermost layer of the paint film, a 10% elastic modulus (M10) of a material constituting the intermediate layer is greater than the 10% elastic modulus (C10) of the material constituting the cover, and a difference (Po10C10) between the 10% elastic modulus (Po10) of the outermost layer of the paint film and the 10% elastic modulus (C10) of the material constituting the cover is 4.0 kgf/cm.sup.2 or more and 50 kgf/cm.sup.2 or less, and a Shore D hardness (Hc) of the material constituting the cover is 40 or less.

Multi-piece golf balls containing a multi-layered core structure are provided. The core structure includes a small, heavy inner core (center) having a relatively high specific gravity, an intermediate core layer, and a surrounding outer core layer. The layers of the core structure may have different hardness gradients. In one preferred embodiment, each core layer has a positive hardness gradient. The center of the core comprises a metal material such as copper, steel, brass, tungsten, titanium, aluminum, and alloys thereof. The intermediate core layer is preferably formed from a thermoset composition such as polybutadiene rubber, and the outer core layer is preferably formed from a thermoplastic composition such as an ethylene acid copolymer. The resulting ball has high resiliency and good spin control.

The present invention provides a golf ball having an aerodynamic subsurface for packing dimples. More particularly, the invention relates to a golf ball having an exterior surface and at least a first subsurface containing at least two dimples located solely on the subsurface and lying below the exterior surface of the golf ball. A transition zone between the exterior surface and the subsurface is disclosed having an angle of transition and a top radius and a bottom radius. According to the present invention, the exterior surface and at least the first subsurface have at least a first and second surface colors that are different.