Abstract: A golf ball includes a spherical core, and a cover covering the spherical core. The spherical core is formed from a rubber composition including a base rubber, a co-cross-linking agent, a cross-linking initiator, an unsaturated fatty acid and/or a metal salt thereof, and an aromatic carboxylic acid and/or a metal salt thereof, the co-cross-linking agent includes an ?,?-unsaturated carboxylic acid having 3 to 8 carbon atoms and/or a metal salt thereof, the unsaturated fatty acid and metal salt thereof excludes an ?,?-unsaturated carboxylic acid having 3 to 8 carbon atoms and a metal salt thereof, and the rubber composition includes a metal compound when the co-cross-linking agent contains only an ?,?-unsaturated carboxylic acid having 3 to 8 carbon atoms.

Abstract: An object of the present invention is to provide a golf ball having a low 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) 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 (d) a carboxylic acid having a benzene ring and/or a salt thereof, provided that the rubber composition further contains (e) a metal compound in 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 flying performance on driver shots. 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, (d) an unsaturated fatty acid and/or a metal salt thereof (excluding an ?,?-unsaturated carboxylic acid having 3 to 8 carbon atoms and/or a metal salt thereof), and (e) a saturated fatty acid and/or a metal salt thereof, provided that the rubber composition further contains (f) 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 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 when JIS-C hardness of the spherical core is measured at points located at distances of 0% (core center), 37.5%, 75.0% and 100% (core surface) from the core center of the spherical core, a hardness difference (Hs?Ho) between a surface hardness (Hs) thereof and a center hardness (Ho) thereof is 20 or more, a ratio ((H37.5?Ho)/(H75.0?Ho)) of a hardness difference (H37.5?Ho) to a hardness difference (H75.0?Ho) is 0.6 or less, and a compression deformation amount (D (mm)) of the spherical core and the 37.5% point hardness (H37.5) satisfy a relation of H37.5??9×D+95.

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 club grip excellent in grip performance in a wet condition. The present invention provides a golf club grip formed from a rubber composition comprising a base rubber and a crosslinking agent, wherein the base rubber comprises a hydrogenated acrylonitrile-butadiene rubber and/or a carboxyl-modified acrylonitrile-butadiene rubber.

Abstract: An object of the present invention is to provide a golf ball showing a low spin rate on driver shots and an excellent shot feeing. The present invention provides a golf ball having a spherical core and at least one cover 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 at least one compound of (d) mercaptobenzoic acids and/or salts thereof, 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, and the spherical core has a hardness difference (Hs?Ho) between a surface hardness (Hs) and a center hardness (Ho) thereof of 20 or more in JIS-C hardness.

Abstract: An object of the present invention is to provide a grip for sporting goods containing an acrylonitrile-butadiene based rubber as a base rubber and having an excellent grip performance and sustainability of grip performance under a wet condition. The present invention provides a grip for sporting goods comprising an outermost surface layer formed from a surface layer rubber composition, wherein the surface layer rubber composition contains (A) a base rubber and (B) a resin having a softening point in a range from 5° C. to 120° C., (A) the base rubber contains an acrylonitrile-butadiene based rubber, and (B) the resin is at least one type selected from the group consisting of a hydrogenated rosin ester, a disproportionated rosin ester, an ethylene-vinyl acetate copolymer, a coumarone resin, a phenol resin, a xylene resin and a styrene resin.

Abstract: An object of the present invention is to provide a grip for sporting goods excellent in tensile strength and having a light weight. The present invention provides a grip for sporting goods comprising a cylindrical portion composed of a cylindrical inner layer and a cylindrical outer layer covering the cylindrical inner layer, wherein the cylindrical inner layer is a porous rubber layer or a porous resin layer, and the cylindrical outer layer is formed from a rubber composition containing an acrylonitrile-butadiene based rubber.

Abstract: An object of the present invention is to provide a golf ball having an excellent flight performance on driver shots. The present invention provides a golf ball comprising a spherical core and at least one cover 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 (d) an unsaturated fatty acid and/or a metal salt thereof excluding an ?,?-unsaturated carboxylic acid having 3 to 8 carbon atoms and/or a metal salt thereof, and provided that the rubber composition further contains (f) a metal compound if only an ?,?-unsaturated carboxylic acid having 3 to 8 carbon atoms is present as (b) the co-crosslinking agent.

Abstract: A method for manufacturing a golf ball showing a great flight distance on driver shots for includes the steps of: preparing a rubber composition containing a base rubber, an ?,?-unsaturated carboxylic acid having 3 to 8 carbon atoms and/or a metal salt thereof as a co-crosslinking agent, a crosslinking initiator and a carboxylic acid and/or a salt thereof; heat pressing the rubber composition at a press temperature ranging from t-40° C. to t-15° C. to mold a spherical core, wherein t ° C. is a one-minute half-life temperature of the crosslinking initiator; and forming at least one cover layer covering the spherical core.

Abstract: An object of the present invention is to provide a golf club grip comprising a layer containing a polar rubber and a layer containing a nonpolar rubber, and excellent in tensile strength. The present invention provides a golf club grip comprising a polar rubber layer and a nonpolar rubber layer, wherein the polar rubber layer is formed from a rubber composition containing a base rubber including a polar rubber in an amount of 50 mass % or more, the nonpolar rubber layer is formed from a rubber composition containing a base rubber including a nonpolar rubber in an amount of 50 mass % or more, the polar rubber layer and the nonpolar rubber layer are laminated via an interlayer formed from an interlayer composition containing an olefin rubber.

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 (d) a carboxylic acid, 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 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 showing a low 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) 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 (d) a carboxylic acid having a heterocyclic ring and/or a salt thereof, provided that the rubber composition further contains (e) a metal compound in 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 traveling a great distance on driver shots. The present invention provides a golf ball comprising a constituting member 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) an crosslinking initiator, wherein (b) the ?, ?-unsaturated carboxylic acid having 3 to 8 carbon atoms and/or the metal salt thereof meets the following conditions (1) and (2) in a volume based distribution, when measuring a particle size thereof with a laser diffraction particle size analyzer; (1) a mode particle size is more than 10 ?m and 50 ?m or less, and (2) a volume ratio of particles having a particle size ranging from 6 ?m to 300 ?m is 60% or more.

Abstract: An object of the present invention is to provide a golf club grip having excellent adhesion between the grip body and the grip end thereof, and excellent durability. The present invention provides a golf club grip comprising a cylindrical grip body having a cylindrical inner layer and a cylindrical outer layer covering the cylindrical inner layer, and a grip end provided on an butt side end of the cylindrical grip body, wherein the cylindrical outer layer is interposed in at least a part of a space between a butt side end edge of the cylindrical inner layer and the grip end.

Abstract: An object of the present invention is to provide a golf ball having a low spin rate on driver shots and excellent in flight distance performance. 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 (d) a salt of a carboxylic acid, 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 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 is formed from a rubber composition containing (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 at least one compound of (d) thiobenzoic acids and/or salts thereof, provided that the rubber composition further contains (e) a metal compound in case of containing only (b) the ?,?-unsaturated carboxylic acid having 3 to 8 carbon atoms as the co-crosslinking agent, and the spherical core has a hardness difference (Hs?Ho) between a surface hardness (Hs) and a center hardness (Ho) thereof of 25 or more in JIS-C hardness.

Abstract: An object of the present invention is to provide a golf ball having a great flight distance on driver shots. The present invention provides a golf ball having a spherical core and at least one cover layer covering the spherical core, wherein when JIS-C hardness, which is measured at nine points obtained by dividing a radius of the spherical core into equal parts having 12.5% intervals therebetween, is plotted against distance (%) from a core center, the spherical core is such that R2 of a linear approximation curve obtained from the least square method is 0.95 or higher, and a hardness difference between a core surface hardness and a core central hardness is 15 or higher in JIS-C hardness.