Sumitomo Rubber Industries Limited

Dunlop Sports Company Limited

Sri Sports Limited

Other

Korea Advanced Institute of Science and Technology

Katsuji Matsunaga

Shigeru Yamago

Dunlap Sports Co. Ltd.

Kazuyoshi Shiga

Takahiro Shigemitsu

Toshiyuki Tarao

Hiroshi Tadaoka

Hikaru Nagakura

Chiemi Mikura

Sho Goji

Masanori Taguchi

Ryota Sakamine

Takehiko Hyodo

Takumi Kaneko

Ryo Murakami

Kai Hayashi

Hiroshi Hasegawa

Ayaka Shindo

Yasuo Naito

Keiji Ohama

Kuniyasu Horiuchi

Hidetaka Inoue

Hitoshi Oyama

Mikio Yamada

Tetsuro Abe

Yuko Kujirai

Masayuki Onishi

Takahiro Sajima

Masatoshi Yokota

Kazuya Kamino

Takashi Sasaki

Hiroaki Tanaka

Kunio Niwa

Fumiya Suzuki

Takeshi Asakura

Katsumi Terakawa

Takanobu Kawamura

Wako Iwamura

Hirotaka Nakamura

Kazuhisa Fushihara

Makoto Sugiya

Kohei Mimura

Kazuyuki Nishioka

Ryo Mashita

Yoshiko Matsuyama

Hiromasa Tsunashima

Shimpei Oyama

Jae Soon Lee

Yuko Sakurai

Hideaki Kimura

Tomoka Kitago

Yuko Oka

Yoshihiko Komori

Sung Chul Kim

Yasuo Kubota

Mutsuhisa Furukawa

Yu Kawabata

Akinori Kitamura

Yuta Shimane

Yohei Miwa

Shoichi Kutsumizu

An adhesive for a tennis ball of the present disclosure includes base rubber and a filler. The base rubber contains, as a main component thereof, liquid rubber having a number average molecular weight of not less than 10,000. The filler has an average nitrogen specific surface area of not less than 40 m/g. A tennis ball of the present disclosure includes a hollow core made of a rubber material. The core includes two hemispherical half cores. The two half cores are adhered to each other by using the adhesive for a tennis ball.

Adhesive for tennis ball

An adhesive for a tennis ball includes base rubber. The base rubber contains, as a main component thereof, liquid rubber having a number average molecular weight of not less than 10,000. The adhesive has a shear viscosity of not greater than 2,000 Pa·s. A tennis ball includes a hollow core made of a rubber material. The core includes two hemispherical half cores. The two half cores are adhered to each other by using the adhesive for a tennis ball.

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) an α,β-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 benzothiazole derivative, and further comprising (e) a metal compound when (b) the co-crosslinking agent consists of the α,β-unsaturated carboxylic acid having 3 to 8 carbon atoms, wherein (d) the benzothiazole derivative is a compound represented by the formula (1) and/or a compound represented by the formula (2).

Rubber composition and crosslinked rubber molded product

An aqueous adhesive for rubber includes rubber latex and an ammonium-salt-based vulcanization acceleration aid. An amount of the ammonium-salt-based vulcanization acceleration aid contained in the aqueous adhesive is preferably not less than 0.01% by weight and not greater than 5.0% by weight in terms of solid content. An aqueous adhesive for a ball includes rubber latex as a main component. A content of an inorganic filler in the aqueous adhesive is not greater than 0.1% by weight in terms of solid content. A ballincludes a hollow coreobtained by crosslinking a rubber composition that contains a vulcanizing agent. The coreis formed of two hemispherical half cores. The two half cores are adhered to each other by using the aqueous adhesive for a ball.

Aqueous adhesive for rubber and aqueous adhesive for ball

The aqueous adhesive for a tennis ball includes rubber latex. The rubber latex is a mixture of liquid rubber latex and solid rubber latex. A ratio of liquid rubber to an entire rubber component contained in the rubber latex is greater than 20% by weight and less than 90% by weight in terms of solid content. The tennis ball includes a seam formed of the aqueous adhesive for a tennis ball.

Aqueous adhesive for tennis ball

An object of the present disclosure is to provide a rubber composition containing an organic sulfur compound from which a molded product having a high hardness can be obtained. The present disclosure provides a rubber composition containing (a) a base rubber, (b) a co-crosslinking agent, (c) a crosslinking initiator, (d) a benzothiazole derivative, and (e) an organic sulfur compound, wherein (d) the benzothiazole derivative is a compound represented by the formula (1) and/or a compound represented by the formula (2). [Rrepresents a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, an aryl group having 4 to 14 carbon atoms, or a metal atom, Rto Rare identical to or different from each other, and represent an electron-withdrawing group or a hydrogen atom, and at least one of Rto Ris an electron-withdrawing group.]

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.

Golf ball

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.

An object of the present invention is to provide a golf ball having oily stain washability or weed juice stain resistance that is adjustable depending on a temperature. The present invention provides a golf ball comprising a golf ball body and a paint film composed of at least one layer and covering the golf ball body, wherein a molecular chain of a base resin constituting an outermost layer located at an outermost side of the paint film has a graft chain, and 80 mole % or more of repeating units constituting the graft chain includes any one of repeating units represented by formulae (1) to (4): [In the formulae (1) to (4), Rto Reach independently represent hydrogen, halogen or an organic group.].

The aqueous adhesive for a tennis ball includes rubber latex. The rubber latex is a mixture of liquid rubber latex and solid rubber latex. When a solid content in the aqueous adhesive is measured at a temperature of 140° C. by a curelastometer, a torque is not less than 0.26 N·m after 10 minutes from start of heating. The tennis ball includes a seam portion formed of the aqueous adhesive for a tennis ball.

An object of the present disclosure is to provide a golf ball having an increased spin rate when being hit with an 8-iron while suppressing rise in a spin rate when being hit with a driver. The present disclosure provides a golf ball comprising a spherical core having an inner core and an outer core, and a cover positioned outside the spherical core, wherein A×a is 12,200 or less and B×b is 20,400 or more, where 'a' represents an average hardness (Shore C) of a hardness (H2.5) at a point of 2.5 mm from a center of the spherical core and a hardness (H5) at a point of 5 mm from the center of the spherical core, “b” represents an average hardness (Shore C) of a hardness (H7.5) at a point of 7.5 mm from the center of the spherical core and a hardness (H9) at a point of 9 mm from the center of the spherical core, “A” represents an impulse difference (kN·μs) between a back spin impulse and a top spin impulse measured using a contact force tester under a condition corresponding to a condition when the golf ball is hit with a driver, and “B” represents an impulse difference (kN·μs) between a back spin impulse and a top spin impulse measured using a contact force tester under a condition corresponding to a condition when the golf ball is hit with an 8-iron.

An object of the present disclosure is to provide a novel golf ball having excellent spin performance on approach shots. The present disclosure provides a golf ball comprising a paint film, wherein a base resin constituting an outermost layer of the paint film is a polyurethane obtained by a reaction between (A) a polyol composition containing a polyol having a side chain and (B) a polyisocyanate composition, a loss modulus (E″) at a temperature of −50° C. is 2.0×10Pa or more, and a loss tangent (tan δ) has a peak with a peak height of 0.1 or more and 0.5 or less in a temperature range of −60° C. or more and −20° C. or less, wherein the loss modulus (E″) and the loss tangent (tan δ) are obtained by measuring a dynamic viscoelasticity of the polyurethane under specific conditions.

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 (μm) is an arithmetic mean roughness of a surface of a cut plane of the cover, and Spc (mm) is an arithmetic mean curvature of a summit of the surface of the cut plane of the cover.

A golf club grip having great anti-slipping performance in the material itself constituting the grip includes an outermost surface layer, wherein at least a part of the outermost surface layer is formed from a rubber composition containing (A) a base rubber and (B) a tackifier having a softening point in a range of from 5° C. to 120° C., and a portion formed from the rubber composition has a loss tangent (tanδ) (30° C., 10 Hz) and a complex elastic modulus (E*) (30° C., 10 Hz) satisfying a relationship of 0.070≤tanδ/(E*)≤0.098.

Golf club grip and golf club

An object of the present invention is to provide a cured product of a golf ball rubber composition imparting excellent durability. The present invention provides a cured product of a golf ball rubber composition cured from a golf ball 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, wherein the cured product of the golf ball rubber composition satisfies the following mathematical formula (1):&#x3c;(0.1&#xd7;)&#x2212;1.30&#x2003;&#x2003;(1) in the formula (), Y represents an effective crosslinking density of the cured product of the rubber composition (mmol/cc), and X represents an amount of the component (b) with respect to 100 parts by mass of (a) the base rubber (parts by mass).

Golf ball rubber composition and golf ball using the same

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Kobe, Japan

Kazuyoshi Shiga