Bridgestone Sports Co., Ltd.

Atsushi Namba

Katsunobu Mochizuki

Masahiro Yamabe

Yusuke Suzuki

Shuto Fukasawa

Kae Iizuka

Hirotaka Shinohara

Yuki Mizuno

The present invention provides a golf ball comprising a core of one or more layers and a cover of one or more layers which encases the core, wherein at least one layer of the cover is formed of the resin composition comprising (a') a polyester resin and (b) an amine-containing polymer having a branched structure. In the golf ball of the present invention, the adhesion property between the core and each cover layer adjacent to the core can be improved and the excellent durability can be obtained.

Resin composition for golf ball, and golf ball

A golf ball material contains The conjugated diene units include butadiene units, the non-conjugated olefin units include units selected from the group consisting of ethylene, propylene and 1-butene units, and the aromatic vinyl units include styrene units. The content of the conjugated diene units in the multi-component copolymer (I) is 5 wt % or more. This golf ball material is soft and has an excellent rebound resilience. Golf balls which use this material in the cover provide golfers with a competitive edge.

Golf ball material and golf ball

A golf ball material contains (i) fine particles that have an average particle size of less than 300 μm and are composed of a crosslinked multi-component copolymer having conjugated diene units, non-conjugated olefin units and aromatic vinyl units; and (ii) a thermoplastic resin. The conjugated diene units include butadiene units, the non-conjugated olefin units include units selected from the group consisting of ethylene, propylene and 1-butene units, the aromatic vinyl units include styrene units, and the content of the conjugated diene units in the multi-component copolymer is 5 wt % or more. This golf ball material is soft, has an excellent rebound resilience and also has a good processability.

Golf ball material, method for producing the same, and golf ball

A resin composition for golf balls includes (a) an acid-containing copolymer having an amount of acid constituent per 100 wt % of the sum of monomer units in the copolymer that is from 1 to 30 wt %, and (b) an amine-containing polymer having a branched structure. The resin composition imparts golf balls with an excellent rebound resilience and also confers an outstanding durability to repeated impact and an outstanding scuff resistance, making it particularly useful as a cover material in golf balls.

A rubber composition for golf balls includes (A) a base rubber, (B) an acrylate ester or methacrylate ester containing an isocyanate group or a blocked isocyanate group, (C) diacrylic acid, dimethacrylic acid or a metal salt thereof, and (D) an organic peroxide. In a golf ball having a core formed of the rubber composition and a cover of one or more layers which encases the core, the rubber composition exhibits a spin rate-lowering effect on shots and can thus improve the flight performance of the ball.

Rubber composition for golf ball, and golf ball

In a golf ball having a two-layer core which includes an inner core layer and an outer core layer and having a cover of one or more layer, the outer core layer is formed of an elastomer composition that includes specific amounts of (A) polybutadiene having a 1,2-bond content of 50 to 95%, (B) a photocurable monomer, oligomer or polymer, and (C) a photopolymerizable initiator. The outer core layer has a thickness of from 1.0 to 4.0 mm, and the two-layer core has a surface hardness on the JIS-C scale of from 75 to 95. The ball is provided with a hardness gradient at the core interior, which lowers the spin rate of the ball, has an improved durability to cracking, and production costs for the outer core layer are kept relatively low.

Golf ball

In a golf ball having a rubber core and an intermediate layer and outermost layer which encase the core, the intermediate layer is formed of a thermoplastic resin composition which has a flexural rigidity of 400 to 500 MPa and a melt flow rate of 15 g/10 min or less and includes 50 to 100 wt % of a magnesium salt of an ethylenically unsaturated carboxylic acid copolymer, the outermost layer is formed of a polyurethane resin composition having a Shore D material hardness of 55 or less, and the golf ball has a deflection within a given range. Compared with conventional golf balls containing the high-rigidity ionomer resins hitherto used as intermediate layer materials, this ball suppresses the spin rate on shots with a driver and long and middle irons, enabling an increased distance to be obtained, and also has a high durability to repeated impact.

A golf ball resin composition includes (a) an olefin-&#x3b1;,&#x3b2;-unsaturated carboxylic acid copolymer and/or a metal ion neutralization product thereof or an olefin-&#x3b1;,&#x3b2;-unsaturated carboxylic acid-&#x3b1;,&#x3b2;-unsaturated carboxylic acid ester copolymer and/or a metal ion neutralization product thereof, (b) a phenolic resin and (c) a compound having at least two oxazoline groups per molecule, wherein the content of component (C) is from 0.1 to 5 parts by weight per 100 parts by weight of components (a) and (b) combined. The resin composition has excellent tensile properties and, when used in a golf ball, provides the ball with an excellent durability without lowering the spin performance and distance performance of the ball. The resin is especially useful as a golf ball cover material for an outermost layer or an intermediate layer.

Resin composition for golf balls, and golf ball

A resin composition for golf balls includes specific amounts of (A) polyurethane or polyurea and (B) an oxazoline group-containing acrylic polymer or an oxazoline group-containing styrene polymer. A golf ball having a core encased by a cover of one or more layers, wherein at least one cover layer is formed of this resin composition, exhibits a good adhesion between adjoining layers, enabling the ball to achieve a high scuff resistance without lowering the initial velocity of the ball.

A matte golf ball which is free of luster and gloss has such a good ball appearance that the injection marks which form during injection molding of the cover are not visible. The golf ball includes a core of at least one layer, a cover of at least one layer, and a paint film. The outermost layer of the cover is formed of a resin composition which includes a thermoplastic resin and a colorant comprising a fluorescent dye or a fluorescent pigment, and has a visible light transmittance with an average value at wavelengths in the 380 to 780 nm spectrum of from 2.0 to 50.0%. The paint film is formed of a urethane-based paint composition containing delustering particles.

A golf ball resin composition includes (A) a styrene-based thermoplastic elastomer having a Shore D hardness of not more than 48 and (B) a thermoplastic resin having a Shore D hardness of at least 49 and containing either styrene monomer units or diene monomer units on the molecule, in a compounding ratio A/B therebetween of from 85/15 to 15/85. Using this resin composition as a golf ball cover material provides the ball with an excellent controllability around the green on shots with a short iron such as a sand wedge. In addition, a sufficient reduction in the spin rate of the ball on shots with a driver is achieved, enabling the distance of the ball to be increased.

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Saitama-ken, Japan

Atsushi Namba