Dunlop Sports Company Limited

Sumitomo Rubber Industries Limited

Sri Sports Limited

Dunlap Sports Co. Ltd.

Chiemi Mikura

Ayaka Shindo

Kazuyoshi Shiga

Ryota Sakamine

Kazuhisa Fushihara

Sho Goji

Toshiyuki Tarao

Shun Kurihara

Mikio Yamada

Kuniyasu Horiuchi

Hidetaka Inoue

Hiroshi Hasegawa

Hitoshi Oyama

Hikaru Nagakura

Hiroshi Tadaoka

Takahiro Shigemitsu

Yumi Kanemitsu

Ayaka Hibi

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 a hardness difference D1 (H75&#x2212;H0) between a hardness H75 at a point radially located at a distance of 75% from a center of the spherical core and a center hardness H0 of the spherical core is 10 or more and 27 or less in Shore C hardness, and a hardness difference D2 (Hs&#x2212;H75) between a surface hardness Hs of the spherical core and the hardness H75 at the point radially located at the distance of 75% from the center of the spherical core is 0 or more and 6.5 or less in Shore C hardness.

Golf ball

An object of the present invention is to provide a novel complex having at least one carbon-carbon double bond and/or carbon-carbon triple bond, and having at least one Diels-Alder reactive functional group such as tetrazine. The present invention provides a complex represented by a formula (1):[MO(RCOO)]&#x2003;&#x2003;(1) 

Complex and process for preparing complex

An object of the present invention is to provide a novel complex having at least two carbon-carbon double bonds and/or carbon-carbon triple bonds. The present invention provides a complex represented by a structural formula (2):  [In the structural formula (2), Mto Mare identical to or different from each other and represent a metal atom, Rto Rare identical to or different from each other and represent a hydrogen atom, an alkyl group having 1 to 24 carbon atoms, an alkenyl group having 2 to 18 carbon atoms or an alkynyl group having 2 to 18 carbon atoms, at least two of Rto Rare the alkenyl group having 2 to 18 carbon atoms or the alkynyl group having 2 to 18 carbon atoms, and at least one of Rto Ris the alkyl group having 6 to 24 carbon atoms].

An object of the present invention is to provide a golf ball having excellent resilience. 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, and (b) a co-crosslinking agent containing (b1) a carboxylic acid represented by a structural formula (1) and/or a metal salt thereof. [In the formula (1), Ato Aeach independently represents a nitrogen atom or a carbon atom. Xrepresents a single bond or a divalent organic group. Rrepresents a hydrogen atom or a monovalent organic group. It is noted that at least one of Ato Ais the carbon atom, and Xand Rbond to the carbon atom. n represents an integer of 0 to 3. When n is 2 or more, a plurality of Rmay be identical to or different from each other, and a plurality of Rmay bond to each other to form a ring structure.]

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, and an unsaturated fatty acid and/or a metal salt thereof, the co-cross-linking agent includes &#x3b1;,&#x3b2;-unsaturated carboxylic acid having 3 to 8 carbon atoms and/or a metal salt thereof, the unsaturated fatty acid and/or metal salt thereof excludes an &#x3b1;,&#x3b2;-unsaturated carboxylic acid having 3 to 8 carbon atoms and a metal salt thereof, an unsaturated aliphatic carboxylic acid that forms the unsaturated fatty acid and/or metal salt thereof has a functional group other than a carboxy group and a carbon-carbon unsaturated bond, and the rubber composition further includes a metal compound when the co-cross-linking agent is only an &#x3b1;,&#x3b2;-unsaturated carboxylic acid having 3 to 8 carbon atoms.

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 &#x3b1;,&#x3b2;-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 &#x3b1;,&#x3b2;-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 &#x3b1;,&#x3b2;-unsaturated carboxylic acid having 3 to 8 carbon atoms is present as (b) the co-crosslinking agent.

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&#xb0; C. to 120&#xb0; 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.

Grip for sporting goods and golf club

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 &#x3b1;,&#x3b2;-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 &#x3b1;,&#x3b2;-unsaturated carboxylic acid having 3 to 8 carbon atoms as the co-crosslinking agent.

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 &#x3b1;,&#x3b2;-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 &#x3b1;,&#x3b2;-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 Rand Rhave a bond dissociation energy of 435 KJ/mol or more. 

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 a hardness difference D1 (H75&#x2212;H0) between a hardness H75 at a point located at a distance of 75% of a core radius from a center of the spherical core and a center hardness H0 of the spherical core is 15 or more and 35 or less in Shore C hardness, a hardness difference D2 (Hs&#x2212;H75) between a surface hardness Hs of the spherical core and the hardness H75 at the point located at the distance of 75% of the core radius from the center of the spherical core is &#x2212;1 or more and 3.5 or less in Shore C hardness, and a hardness difference D3 ((H0+H75)/2&#x2212;H37.5) between a hardness of (the center hardness H0 of the spherical core+the hardness H75 at the point located at the distance of 75% of the core radius from the center of the spherical core)/2 and a hardness H37.5 at a point located at a distance of 37.5% of the core radius from the center of the spherical core is 0.5 or more and 6.5 or less in Shore C hardness.

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 &#x3b1;,&#x3b2;-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 &#x3b1;,&#x3b2;-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 &#x3b1;,&#x3b2;-unsaturated carboxylic acid having 3 to 8 carbon atoms as the co-crosslinking agent.

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.

Golf club grip, golf club and method for producing golf club grip

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&#xb1;30 cmat a surface thereof and absorbance of the absorption peak appeared at 1560&#xb1;30 cmat a center thereof of 0.024 or more, when measuring the spherical core with a Fourier transform infrared spectrophotometer.

An object of the present invention is to provide a golf club grip showing a good feeling both at hitting and at waggling. The present invention provides a golf club grip comprising a cylindrical portion for inserting a shaft, wherein the cylindrical portion has a compression strain in a range from 46% to 55% at a compression stress of 20 kg/cm, and a compression strain in a range from 63% to 69% at a compression stress of 120 kg/cm.

Golf club grip and golf club

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 &#x3b1;,&#x3b2;-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 &#x3b1;,&#x3b2;-unsaturated carboxylic acid having 3 to 8 carbon atoms as the co-crosslinking agent.

Growing community of inventors

Kobe, Japan

Chiemi Mikura