Abstract: An object of the present disclosure is, for a golf ball comprising a cover containing a polyurethane as a resin component, to improve formability of the cover and increase productivity of the golf ball while inhibiting lowering of scratch resistance of the cover. The present disclosure provides a golf ball comprising a spherical core and a cover covering the spherical core, wherein the cover is formed from a cover composition containing (A) a thermoplastic polyurethane and (B) a carboxylic acid having a molecular weight of 1000 or less as a resin component.

Abstract: An object of the present disclosure is, for a golf ball comprising a cover containing a polyurethane as a resin component, to improve formability of the cover and increase productivity of the golf ball while suppressing lowering in scratch resistance of the cover. The present disclosure provides a golf ball comprising a spherical core and a cover covering the spherical core, wherein the cover contains (A) a thermoplastic polyurethane as a resin component, and a difference ?v (v1?v2) between a wave number (v1) of an absorption peak attributed to an N—H group not forming a hydrogen bond in (A) the thermoplastic polyurethane and a wave number (v2) of an absorption peak attributed to an N—H group forming a hydrogen bond with a carbonyl oxygen of a urethane group in (A) the thermoplastic polyurethane ranges from 100.0 cm?1 to 109.0 cm?1 when the cover is measured with a Fourier transform infrared spectrometer under the predetermined measuring conditions.

Abstract: An object of the present disclosure is, for a golf ball comprising a cover containing a polyurethane as a resin component, to improve the moldability of the cover and increase the productivity of the golf ball while suppressing lowering in the scratch resistance of the cover. The present disclosure provides a golf ball comprising a spherical core and a cover covering the spherical core, wherein the cover is formed from a cover composition containing (A) a thermoplastic polyurethane and (B) an olefin/unsaturated carboxylic acid copolymer and/or an olefin/unsaturated carboxylic acid/unsaturated carboxylic acid ester copolymer as a resin component, and an amount of (A) the thermoplastic polyurethane is 50 mass % or more in the resin component.

Abstract: An object of the present disclosure is to provide a golf ball having good shot feeling and excellent durability while having non-lowered resilience. The present disclosure provides a golf ball comprising a spherical core and one or more cover layers disposed outside the spherical core, wherein at least one layer of the cover layers contains (A) a base resin and (B) a polyethylene oxide.

Abstract: An object of the present disclosure is to provide a rubber composition from which a crosslinked rubber molded product having good softness and excellent resilience performance can be obtained. The present disclosure provides a rubber composition containing (a) a base rubber, (b) a co-crosslinking agent, (c) a crosslinking initiator, and (d) an organic sulfur compound, wherein (d) the organic sulfur compound includes (d1) a polythiophene compound having two or more thiophene rings in the molecule.

Abstract: An object of the present disclosure is to provide a golf ball having good shot feeling and excellent durability and not having lowered resilience even if a hard cover material is used. The present disclosure provides a golf ball comprising a spherical core, and a cover disposed outside the spherical core and composed of one or more layers, wherein at least one cover layer contains (A) a base resin, and (B) at least one member selected from the group consisting of a polyrotaxane, a polyethylene oxide, a polypropylene oxide, a polycaprolactone and a liquid polymer, and Sa×Spc?100 wherein Sa (?m) is an arithmetic mean roughness of a surface of a cut plane of the cover, and Spc (mm?1) is an arithmetic mean curvature of a summit of the surface of the cut plane of the cover.

Abstract: An object of the present disclosure is to provide a rubber composition from which a crosslinked rubber molded product having excellent resilience performance can be obtained. The present disclosure provides a rubber composition containing (a) a base rubber, (b) a co-crosslinking agent, and (c) a crosslinking initiator, wherein (b) the co-crosslinking agent includes (b1) a metal complex, and (b1) the metal complex is composed of (b11) a metal component, (b12) a ligand derived from an ?,?-unsaturated carboxylic acid compound having 3 to 8 carbon atoms, and (b13) a ligand derived from a mercaptobenzothiazole-based compound.

Abstract: An object of the present disclosure is to provide a golf ball having good shot feeling and excellent durability while having non-lowered resilience. The present disclosure provides a golf ball comprising a spherical core and one or more cover layers disposed outside the spherical core, wherein at least one layer of the cover layers contains (A) a base resin and (B) a polyethylene oxide.

Abstract: An object of the present disclosure is to provide a rubber composition from which a crosslinked rubber molded product having good softness and excellent resilience performance can be obtained. The present disclosure provides a rubber composition containing (a) a base rubber, (b) a co-crosslinking agent, (c) a crosslinking initiator, and (d) an organic sulfur compound, wherein (d) the organic sulfur compound includes (d1) a compound represented by the formula (1) and/or (d2) a compound represented by the formula (2).

Abstract: An object of the present disclosure is to provide a golf ball having good shot feeling and excellent durability and not having lowered resilience even if a hard cover material is used. The present disclosure provides a golf ball comprising a spherical core, and a cover disposed outside the spherical core and composed of one or more layers, wherein at least one cover layer contains (A) a base resin, and (B) at least one member selected from the group consisting of a polyrotaxane, a polyethylene oxide, a polypropylene oxide, a polycaprolactone and a liquid polymer, and Sa×Spc?100 wherein Sa (?m) is an arithmetic mean roughness of a surface of a cut plane of the cover, and Spc (mm?1) is an arithmetic mean curvature of a summit of the surface of the cut plane of the cover.

Abstract: An object of the present disclosure is to provide a rubber composition from which a crosslinked rubber molded product having good softness and excellent resilience performance can be obtained. The present disclosure provides a rubber composition containing (a) a base rubber, (b) a co-crosslinking agent, (c) a crosslinking initiator, and (d) an organic sulfur compound, wherein (d) the organic sulfur compound includes (d1) a polythiophene compound having two or more thiophene rings in the molecule.

Abstract: An object of the present invention is to provide a golf ball having a decreased spin rate on driver shots. The present invention provides a golf ball comprising a spherical core and at least one cover layer covering the spherical core, wherein the spherical core is formed from a rubber composition containing (a) a base rubber, (b) a compound represented by the formula (1) as a co-crosslinking agent, and (c) a crosslinking initiator, (R1COO)M(OCOR2)m??(1) in the formula (1), M represents a metal atom, m represents 1 or 2, R1 and R2 are different from each other, represent an alkenyl group having 2 to 30 carbon atoms or an alkynyl group having 2 to 30 carbon atoms and have a carbon-carbon double bond or a carbon-carbon triple bond at an ?-position carbon atom bonding to the carbonyl group, and when m is 2, two of R2 may be identical to or different from each other.

Abstract: An object of the present invention is to provide a golf ball having a decreased spin rate on driver shots. The present invention provides a golf ball comprising a spherical core and at least one cover layer covering the spherical core, wherein the spherical core is formed from a rubber composition containing (a) a base rubber, (b) two or more ?,?-unsaturated carboxylic acids having 3 to 14 carbon atoms and having no substituent group at a carbon atom bonding to the carboxy group, and/or a metal salt thereof, and (c) a crosslinking initiator.

Abstract: An object of the present invention is to provide a golf ball having excellent resilience performance. The present invention provides a golf ball comprising a constituent member, wherein at least a part of the constituent member is formed from a rubber composition containing (a) a base rubber, (b) a co-crosslinking agent, (c) a crosslinking initiator, and (d) an organic sulfur compound, wherein (d) the organic sulfur compound contains at least one member selected from the group consisting of a thiophenol having a halogenated sulfanyl group, a metal salt of a thiophenol having a halogenated sulfanyl group, and a diphenyl disulfide having a halogenated sulfanyl group.

Abstract: An object of the present invention is to provide a golf ball having a decreased spin rate on driver shots. The present invention provides a golf ball comprising a spherical core and at least one cover layer covering the spherical core, wherein the spherical core is formed from a rubber composition containing (a) a base rubber, (b) a compound represented by the formula (1) as a co-crosslinking agent, and (c) a crosslinking initiator, (R1COO)M(OCOR2)m??(1) in the formula (1), M represents a metal atom, m represents 1 or 2, R1 and R2 are different from each other, represent an alkenyl group having 2 to 30 carbon atoms or an alkynyl group having 2 to 30 carbon atoms and have a carbon-carbon double bond or a carbon-carbon triple bond at an ?-position carbon atom bonding to the carbonyl group, and when m is 2, two of R2 may be identical to or different from each other.

Abstract: An object of the present invention is to provide a golf ball having a decreased spin rate on driver shots. The present invention provides a golf ball comprising a spherical core and at least one cover layer covering the spherical core, wherein the spherical core is formed from a rubber composition containing (a) a base rubber, (b) two or more ?,?-unsaturated carboxylic acids having 3 to 14 carbon atoms and having no substituent group at a carbon atom bonding to the carboxy group, and/or a metal salt thereof, and (c) a crosslinking initiator.

Abstract: An object of the present invention is to provide a golf ball having excellent resilience performance. The present invention provides a golf ball comprising a constituent member, wherein at least a part of the constituent member is formed from a rubber composition containing (a) a base rubber, (b) a co-crosslinking agent, (c) a crosslinking initiator, and (d) an organic sulfur compound, wherein (d) the organic sulfur compound contains at least one member selected from the group consisting of a thiophenol having a halogenated sulfanyl group, a metal salt of a thiophenol having a halogenated sulfanyl group, and a diphenyl disulfide having a halogenated sulfanyl group.

Abstract: An object of the present invention is to provide a golf ball excellent in flying performance, in particular, to provide a golf ball traveling a great flight distance. The present invention provides a golf ball having a spherical core and at least one cover layer covering the spherical core, wherein the spherical core is formed from a rubber composition containing (a) a base rubber, (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 (d1) an aromatic carboxylic acid or (d2) an aromatic carboxylic acid salt, provided that the rubber composition further contains (e) a metal compound in the case of containing only (b) the ?,?-unsaturated carboxylic acid having 3 to 8 carbon atoms as the co-crosslinking agent.

Abstract: An object of the present invention is to provide a golf ball having excellent resilience performance. The present invention provides a golf ball having a spherical core and at least one cover layer, wherein the spherical core is formed from a rubber composition containing (a) a base rubber, (b) an ?,?-unsaturated carboxylic acid having 3 to 8 carbon atoms and/or a metal salt thereof as a co-crosslinking agent, and (c) a crosslinking initiator, provided that the rubber composition further contains (d) a metal compound in the case of containing only (b) the ?,?-unsaturated carboxylic acid having 3 to 8 carbon atoms as the co-crosslinking agent, wherein (c) the crosslinking initiator includes a peroxy ketal represented by the formula (1), and substituents represented by R1 and R2 have a bond dissociation energy of 435 KJ/mol or more.

Abstract: An object of the present invention is to provide a golf ball showing a great flight distance on driver shots. The present invention provides a golf ball comprising a spherical core and at least one cover layer covering the spherical core, wherein the spherical core has a difference between absorbance of the absorption peak appeared at 1560±30 cm?1 at a surface thereof and absorbance of the absorption peak appeared at 1560±30 cm?1 at a center thereof of 0.024 or more, when measuring the spherical core with a Fourier transform infrared spectrophotometer.