A golf ball for amateur golfers is endowed with both an excellent flight and a good, soft feel at impact when hit by the average golfer whose head speed is not very high. The golf ball, which includes a core and a cover, has a compressive deformation A when subjected to a final load of 5 kgf from an initial load of 0.2 kgf that is 0.18 mm or less, a compressive deformation B when subjected to a final load of 50 kgf from an initial load of 5 kgf that is from 1.30 to 1.69 mm and a compressive deformation C when subjected to a final load of 90 kgf from an initial load of 5 kgf that is from 2.45 to 2.90 mm.

In a multi-piece solid golf ball made up of, successively, a core, an intermediate layer and a cover having numerous dimples on the surface thereof, the intermediate layer is formed of a resin material and the cover is formed of a urethane resin material, each having a specific respective Shore D hardness. The ball has a specific (intermediate layer thickness)/(core diameter) value and a specific (cover thickness)/(core diameter) value, and the core has a specific deflection and has a specific hardness profile from a center to a surface thereof. This golf ball provides an increased distance and has both a soft feel when played and a high durability to repeated impact.

In a golf ball having a core, an intermediate layer and a cover, the intermediate layer-encased sphere has a higher surface hardness than the ball. The core hardness profile in the ball is designed such that the core surface has a Shore C hardness value which is at least 28 higher than the Shore C hardness value at the core center, and the surface areas A to F calculated from hardness differences between positions located at specific distances in the core and differences between the specific distances satisfy a specific formula. This golf ball has an excellent flight performance when struck by skilled amateur golfers and professionals, and also has a good controllability on shots with an iron.

A multi-piece solid golf ball having a two-layer core with an inner core layer and an outer core layer and having a cover of at least two layers including an intermediate layer and an outer layer with numerous dimples on the surface is characterized in that the hardest cover layer has a specific material hardness and the ball has a specific value obtained by subtracting the surface hardness of the overall core from the surface hardness of the hardest cover layer, a specific deflection, and a specific value obtained by subtracting the initial velocity of the inner core layer from the initial velocity of the sphere consisting of the inner core layer encased by the outer core layer. This golf ball enables relatively low head speed golfers to achieve a good distance on full shots with drivers and iron clubs and also provides a soft, comfortable feel at impact.

To provide a golf ball that can prevent a decrease in carry distance of a driver shot when it rains and also, can exert excellent spinning performance upon an approach shot. The golf ball of the present invention includes a core, a cover that is provided on an outer side of the core and is provided with 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. The golf ball has a dynamic friction coefficient of 0.52 or more. The material constituting the outermost layer comprises a urethane coating that contains a water repellent additive, and the water repellent additive includes a fluorinated surfactant, silicone-modified acrylate or hydrophobic silica.

In a golf ball having a core, a cover of at least one layer and a paint film layer formed on a surface of the cover, the paint film layer has an elastic work recovery of at least 60%, the cover layer in contact with the paint film layer has a material hardness on the Shore D scale of at least 55 and, letting M be the elastic work recovery (%) of the paint film layer and N be the material hardness (Shore D hardness) of the cover layer, MN>0. The ball surface is scratch-resistant and has an excellent durability, and the ball has a reduced spin rate on shots with a driver or a long iron, resulting in an increased carry.

Golf balls having a multi-layered 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 is used to form the foam center. The foam inner core preferably includes a fully-foamed center region and a partially or completely-collapsed foam outer region. The hardness of the fully-foamed region is different than the hardness of the collapsed foam region. Non-foamed thermoset or thermoplastic materials such as polybutadiene rubbers or ethylene acid copolymer ionomer may be used to form the outer core layer. The ball further includes a cover that may be multi-layered. The foam cores have good resiliency.

A golf ball includes a main body and a paint layer positioned outside the main body. The paint layer includes an inner layer and an outer layer positioned outside the inner layer. When an indentation depth (nm) is measured on a cross-section along a plane passing through a central point of the golf ball when a force of 30 mgf is applied to the cross-section in a direction perpendicular to the cross-section, an indentation depth Di on a cross-section of the inner layer is smaller than an indentation depth Do on a cross-section of the outer layer. A thickness To of the outer layer is larger than a thickness Ti of the inner layer.

A golf ball includes a core and a cover. The core is formed of a material molded under heat from a rubber composition. The rubber composition includes components (A) through (C). The components (A) through (C) are (A) a base rubber, (B) an organic peroxide, and (C) a metal salt containing hydration water.

A rubber composition for golf balls includes (a) a base rubber, (b) a co-crosslinking agent which is an ,-unsaturated carboxylic acid and/or a metal salt thereof, (c) an organic peroxide, (d) water or an alcohol, and (e) an antioxidant which is a benzoimidazole of the following general formula and/or a metal salt thereof. When the rubber composition is used in constituent members of a golf ball, especially the core, the golf ball exhibits low spin properties on shots, resulting in an improved flight performance and enabling a good durability to be maintained.