In a multi-piece solid golf ball having a core, an envelope layer, an intermediate layer and a cover, the core is formed primarily of a base rubber, the envelope layer, intermediate layer and cover are each formed of a resin material, and the envelope layer is formed into two layersan inner layer and an outer layer. The center and surface hardnesses of the core, the surface hardness of the inner envelope layer-encased sphere, the surface hardness of the outer envelope layer-encased sphere, the surface hardness of the intermediate layer-encased sphere and the surface hardness of the ball together satisfy a specific relationship. This ball exhibits a flight performance capable of satisfying professional golfers and skilled amateurs and possesses an excellent controllability on approach shots, in addition to which it has a good feel at impact and an excellent scuff resistance.

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 the ball is subjected to a final load of 5 kgf from an initial load state of 0.2 kgf that is 0.18 mm or less, a compressive deformation B when the ball is subjected to a final load of 15 kgf from an initial load state of 5 kgf that is from 0.30 to 0.38 mm, a compressive deformation C when the ball is subjected to a final load of 60 kgf from an initial load state of 5 kgf that is from 1.70 to 2.03 mm and a compressive deformation D when the ball is subjected to a final load of 130 kgf from an initial load state of 10 kgf that is from 3.10 to 3.80 mm.

An object of the present invention is to provide a golf ball having excellent spin performance on approach shots under a wet condition and excellent spin performance on approach shots under a condition that there is grass between the golf ball and the club face. The present invention provides a golf ball comprising a golf ball body and a paint film composed of at least one layer and formed on a surface of the golf ball body, wherein an outermost layer of the paint film located at the outermost layer of the golf ball contains a base resin and a porous filler, the base resin contains a polyurethane obtained by a reaction between a polyisocyanate composition and a polyol composition, and the porous filler contains SiO.sub.2 in an amount of 50 mass % or more as a constituent component.

An object of the present invention is to provide a golf ball having excellent spin performance on approach shots under a wet condition and excellent spin performance on approach shots under a condition that there is grass between the golf ball and the dub face. The present invention provides a golf ball comprising a golf ball body and a paint film composed of at least one layer and formed on a surface of the golf ball body, wherein an outermost layer of the paint film located at the outermost layer of the golf ball contains a base resin and a porous filler, the base resin contains a polyurethane obtained by a reaction between (A) a polyisocyanate composition and (B) a polyol composition containing a urethane polyol as a polyol component, the porous filler contains SiO.sub.2 in an amount of 50 mass % or more as a constituent component, and a loss tangent (tan ) of the outermost layer of the paint film measured with a dynamic viscoelasticity measuring apparatus under following conditions has a peak temperature in a range of from 43 C. to 40 C.

An object of the present invention is to provide a golf ball having excellent approach spin performance under a dry condition and excellent approach spin performance under a condition that there is grass between the golf ball and the club face. 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 paint film is composed of at least one layer, and an outermost paint film layer located at the outermost layer of the golf ball contains, as a base resin, a polyurethane obtained by a reaction between (A) a polyisocyanate composition and (B) a polyol composition, (B) the polyol composition contains a urethane polyol as a polyol component, and the outermost paint film layer has a dynamic friction coefficient of from 0.65 to 1.2 measured with a dynamic friction tester under specific conditions.

An object of the present invention is to provide a golf ball having excellent approach spin performance under a dry condition and excellent approach spin performance under a condition that there is grass between the golf ball and the club face. 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 paint film is composed of at least one layer, and an outermost paint film layer located at the outermost layer of the golf ball contains, as a base resin, a polyurethane obtained by a reaction between (A) a polyisocyanate composition and (B) a polyol composition, (B) the polyol composition contains a urethane polyol as a polyol component, and a loss tangent (tan ) of the outermost paint film layer measured with a dynamic viscoelasticity measuring apparatus under specific conditions has a peak temperature in a range of from 40 C. to 40 C.

An object of the present invention is to provide a golf ball having excellent approach spin performance under a dry condition and excellent approach spin performance under a condition that there is grass between the golf ball and the club face. 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 paint film is composed of at least one layer, and an outermost paint film layer located at the outermost layer of the golf ball contains, as a base resin, a polyurethane obtained by a reaction between (A) a polyisocyanate composition and (B) a polyol composition, and the outermost paint film layer has a dynamic friction coefficient of from 0.75 to 1.5 measured with a dynamic friction tester under specific conditions.

Disclosed is a carbon nanotube golf ball having improved hitting feel and durability, and antistatic property comprising: a core having CNT/ionomer-dispersion; a cover formed on the core; and an antistatic finish on the top cover. Herein, CNT/ionomer-dispersions having a diameter of 10 to 3,000 m are produced in advance using an independent process, and then applied to the present art. The top cover is provided with antistatic finish using a CNT coating solution for keeping the clean surface during the golf play.

A golf ball for amateur golfers is endowed with both an excellent flight and a good, solid feel at impact when hit by the average amateur golfer having a fast head speed. 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 0.85 to 1.16 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 1.90 to 2.25 mm.

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.