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.

An object of the present invention is to provide a golf ball having improved ball speed or aerodynamic performance on a rainy day or the like by controlling the formulation of the paint film. The present invention provides a golf ball comprising a golf ball body and a paint film covering the golf ball body, wherein a paint film surface of the golf ball has a water contact angle A1 of 70 or more and a water sliding angle B1 of less than 50. The present invention also provides a golf ball comprising a golf ball body and a paint film covering the golf ball body, wherein when a sheet consisting of a slab formed from a composition constituting a golf ball body surface and a coating film formed by applying a paint constituting the paint film on the slab is prepared, a coating film surface of the sheet has a water contact angle A2 of 90 or more and a water sliding angle B2 of less than 52.

An object of the present invention is to provide a golf ball travelling a great flight distance on driver shots, having enhanced controllability on approach shots under a wet condition, and being excellent in stain resistance and shot feeling. The present invention provides a golf ball comprising a golf ball body having a cover, and a paint film covering the golf ball body, wherein a 10% elastic modulus of the paint film is 75 kgf/cm.sup.2 or less, a storage modulus (E.sub.150) at 150 C. of the paint film obtained by measuring dynamic viscoelasticity of the paint film is 1.010.sup.7 Pa or more, an indentation depth of the paint film measured with a nanoindenter in a state that the paint film is formed on the surface of the golf ball body is 1250 nm or more, and a material hardness of the cover is 50 or more in Shore D hardness.

An object of the present invention is to provide a golf ball showing increased controllability on approach shots for less than 40 yards and showing excellent shot feeling. In the inventive golf ball, the paint film is formed from a curing type paint composition including: a base material containing a polyrotaxane, and a curing agent containing a polyisocyanate, and wherein the polyrotaxane has a cyclodextrin, a linear molecule included in a cyclic structure of the cyclodextrin in a manner of piercing through the cyclic structure of the cyclodextrin, and a blocking group located at both ends of the linear molecule to prevent disassociation of the cyclodextrin, and at least a part of hydroxyl groups of the cyclodextrin is modified with a caprolactone chain via OC.sub.3H.sub.6O group.

The present invention relates to a composition, comprising a binder resin, a block copolymer which comprises at least a block A and a block B, wherein the block A comprises monomer units derived from a compound selected from (meth)acrylic acid, a (meth)acrylic acid ester, a (meth)acrylamide, a vinyl aromatic compound, or any mixture thereof, the block B comprises monomer units derived from a compound selected from a fluorinated (meth)acrylic ester having the following formula (I):
H.sub.2CC(R.sub.1)(C(O)OR.sub.F-1)(I) wherein R1 is H or methyl; and R.sub.F-1 is an organic residue containing a perfluorinated C.sub.4-6 alkyl group, a fluorinated alpha-olefin having the following formula (II):
H.sub.2CCH(R.sub.F-2)(II) wherein R.sub.F-2 is an organic residue containing a perfluorinated C.sub.4-6 alkyl group, i.e., (CF.sub.2).sub.3-5CF.sub.3 or any mixture thereof.

An object of the present invention is to provide a golf ball showing an increased spin rate on approach shots under a wet condition while maintaining a spin rate on approach shots under a dry condition. 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 has a multi-layered construction composed of two or more layers, and a difference (M.sub.outM.sub.in) between a 10% elastic modulus (M.sub.out) of an outermost layer of the paint film and a 10% elastic modulus (M.sub.in) of an innermost layer of the paint film is 25 kgf/cm.sup.2 or more.

An object of the present invention is to provide a golf ball showing increased controllability on approach shots for less than 40 yards and showing excellent shot feeling. In the inventive golf ball, the paint film is formed from a curing type paint composition including: a base material containing a polyrotaxane, and a curing agent containing a polyisocyanate, and wherein the polyrotaxane has a cyclodextrin, a linear molecule included in a cyclic structure of the cyclodextrin in a manner of piercing through the cyclic structure of the cyclodextrin, and a blocking group located at both ends of the linear molecule to prevent disassociation of the cyclodextrin, and at least a part of hydroxyl groups of the cyclodextrin is modified with a caprolactone chain via OC.sub.3H.sub.6O group.

An object of the present invention is to provide a golf ball showing increased controllability on approach shots for less than 40 yards and showing excellent shot feeling. In the inventive golf ball, the paint film is formed from a curing type paint composition including: a base material containing a polyrotaxane, and a curing agent containing a polyisocyanate, and wherein the polyrotaxane has a cyclodextrin, a linear molecule included in a cyclic structure of the cyclodextrin in a manner of piercing through the cyclic structure of the cyclodextrin, and a blocking group located at both ends of the linear molecule to prevent disassociation of the cyclodextrin, and at least a part of hydroxyl groups of the cyclodextrin is modified with a caprolactone chain via OC.sub.3H.sub.6O group.

The present invention relates to a composition, comprising a binder resin, a block copolymer which comprises at least a block A and a block B, wherein the block A comprises monomer units derived from a compound selected from (meth)acrylic acid, a (meth)acrylic acid ester, a (meth)acrylamide, a vinyl aromatic compound, or any mixture thereof, the block B comprises monomer units derived from a compound selected from a fluorinated (meth)acrylic ester having the following formula (I): H.sub.2CC(R.sub.1)(C(0)OR.sub.F-1), wherein R1 is H or methyl; and R.sub.F-1 is an organic residue containing a perfluorinated C.sub.4-6 alkyl group, a fluorinated alpha-olefin having the following formula (II): H.sub.2CCH(R.sub.F-2) (II) wherein R.sub.F-2 is an organic residue containing a perfluorinated C.sub.4-6 alkyl group, i.e. (CF.sub.2).sub.3-5CF.sub.3 or any mixture thereof.

The present invention relates to a composition, comprising a binder resin, a block copolymer which comprises at least a block A and a block B, wherein the block A comprises monomer units derived from a compound selected from (meth)acrylic acid, a (meth)acrylic acid ester, a (meth)acrylamide, a vinyl aromatic compound, or any mixture thereof, the block B comprises monomer units derived from a compound selected from a fluorinated (meth)acrylic ester having the following formula (I):

H.sub.2CC(R.sub.1)(C(O)OR.sub.F1)(I) wherein R1 is H or methyl; and R.sub.F1 is an organic residue containing a perfluorinated C.sub.4-6 alkyl group, a fluorinated alpha-olefin having the following formula (II):

H.sub.2CCH(R.sub.F2)(II) wherein R.sub.F2 is an organic residue containing a perfluorinated C.sub.4-6 alkyl group, i.e., (CF.sub.2).sub.3-5CF.sub.3 or any mixture thereof.