Abstract: An object of the present invention is to provide a golf ball having high resilience. The gist of the present invention resides in selecting an organic sulfur compound used for a golf ball rubber composition containing (a) a base rubber, (b) a co-crosslinking agent, (c) a crosslinking initiator, and (d) the organic sulfur compound from organic sulfur compounds having specific structures such that a sum of substituent constants of the substituents X in a structure represented by the following formula (4) is 0.2 or more and SP value of the structure represented by the following formula (4) is in a range from 19.0 (J/cm3)1/2 to 24.0 (J/cm3)1/2 and using the same.

Abstract: An object of the present invention is to provide a golf ball traveling 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 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 specific organic peroxide, and (d) a carboxylic acid and/or a salt 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.

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 (d) a mercaptocarboxylic acid derivative and/or a dithiodicarboxylic acid derivative.

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 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: 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) an acid and/or a salt 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, wherein (d) the acid and/or the salt thereof has a relative solubility parameter to (a) the base rubber and (b) the ?,?-unsaturated carboxylic acid having 3 to 8 carbon atoms and/or the metal salt thereof ranging from 0.45 to 1.10.

Abstract: An object of the present invention is to provide a golf ball traveling 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, (d) a carboxylic acid having 4 to 30 carbon atoms and/or a salt thereof, and (e) a halogen-substituted thiophenol and/or a metal salt thereof as an organic sulfur compound, 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: The present invention provides a golf ball comprising a spherical core and at least one cover layer covering the spherical core, wherein the cover is formed from a polyurethane composition containing a polyurethane elastomer as a resin component, the polyurethane composition satisfying properties of rebound resilience of 54% or more and a shear loss modulus G? of 5.03×106 Pa or less when measured in a shear mode using a dynamic viscoelasticity measuring apparatus at the conditions of the temperature of 0° C., and the oscillation frequency of 10 Hz, and the spherical core has a hardness distribution that R2 of a linear approximate curve determined by a least-squares method is 0.95 or more, when plotting JIS-C hardness measured at a center, a surface and at intervals of 2.5 mm from the center of the spherical core, versus distances from the center of the spherical core.

Abstract: A golf ball includes a spherical core and a cover covering the spherical core, wherein the cover is formed from a polyurethane composition containing a polyurethane elastomer as a resin component, the polyurethane composition has a shear loss modulus G? of more than 5.03×106 Pa and 1.17×108 Pa or less when measured in a shear mode using a dynamic viscoelasticity measuring apparatus at the conditions of the temperature of 0° C., and the oscillation frequency of 10 Hz, the golf ball has a hardness distribution that R2 of a linear approximate curve determined by a least-squares method is 0.95 or more, when plotting center hardness (JIS-C) of the spherical core, hardness (JIS-C) measured at intervals of 2.5 mm from the center of the spherical core, surface hardness (JIS-C) of the spherical core, and slab hardness (JIS-C) of the cover versus distances from the center of the spherical core.

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.

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 (d) a branched carboxylic acid 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 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 (d) a carboxylic acid having 1 to 14 carbon atoms, 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 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 (d) a salt of a carboxylic acid having 1 to 13 carbon atoms, 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 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 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.

Abstract: An object of the present invention is to provide a golf ball traveling a great distance of a driver shot. 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) a carboxylic acid and/or a salt thereof, and (e) an organic sulfur compound having a naphthalene ring, 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 (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 having high resilience. The gist of the present invention resides in selecting an organic sulfur compound used for a golf ball rubber composition containing (a) a base rubber, (b) a co-crosslinking agent, (c) a crosslinking initiator, and (d) the organic sulfur compound from organic sulfur compounds having specific structures such that a sum of substituent constants of the substituents X in a structure represented by the following formula (4) is 0.2 or more and SP value of the structure represented by the following formula (4) is in a range from 19.0 (J/cm3) using the same.

Abstract: An optical film comprising an optical base film having one surface or both surface thereof multilayers of pressure-sensitive adhesive layers, wherein the multilayers comprise a combination of pressure-sensitive adhesive layers each having a different stress relaxation time, the pressure-sensitive adhesive layer having the longest stress relaxation time is disposed at the outermost side, and the thickness thereof is 80% or less of the total thickness of the pressure-sensitive layers. The optical film is excellent in heat resistance and moisture resistance, is not difficult to cause foaming and pealing at the interface between a liquid crystal cell and the film even in using at high temperature and high moisture atmosphere, and is suitable for providing a liquid crystal display.

Abstract: A medical pressure-sensitive adhesive and a medical bandage formed using the same are disclosed. The medical pressure-sensitive adhesive comprises an acrylic polymer and a specific liquid or pasty component which is in a liquid state or pasty state at room temparature and is compatible with the acrylic polymer. The medical pressure-sensitive adhesive is suitable for use as a plaster, a pressure-sensitive dressing, a poultice and the like.