Abstract: In a golf ball having a core of at least one layer and a cover of at least one layer encasing the core, at least one layer of the cover is formed of a resin composition which includes (I) a polyurethane or a polyurea, (II) a thermoplastic polyester elastomer and (III) an aromatic vinyl elastomer. The thermoplastic polyester elastomer serving as component (II) and the aromatic vinyl elastomer serving component (III) have specific respective contents and properties, including Shore D hardnesses and rebound resiliences. The golf ball has an excellent controllability on approach shots without a loss of distance on driver shots. In addition, the scuff resistance and moldability are good.

Abstract: A control system of a power converter includes a plurality of carrier wave generating units which are respectively provided for a plurality of power converters connected between a plurality of DC power supplies and a common AC power supply and which are configured to respectively generate carrier waves on the basis of an AC voltage of the AC power supply. The control system of the power converter can thereby synchronize carrier phases of a plurality of power converters.

Abstract: In a golf ball having a rubber core of at least one layer and a cover of at least one layer that encases the core, at least one layer of the cover is formed of a resin composition which includes (A) a polyurethane or a polyurea, (B) an alkyl methacrylate/alkyl acrylate copolymer, and (C) a fatty acid amide. The golf ball has an excellent mold releasability during molding of the cover while retaining a good spin rate on approach shots, scuff resistance and paint film durability.

Abstract: In a golf ball having a rubber core of at least one layer and a cover of at least one layer encasing the core, at least one layer of the cover is formed of a resin composition that includes (I) a polyurethane or a polyurea and (II) a (meth)acrylic block copolymer, the (meth)acrylic block copolymer serving as component (II) being included in an amount of 20 parts by weight or less per 100 parts by weight of component (I). The golf ball has an excellent controllability on approach shots and is able to maintain a good scuff resistance and moldability.

Abstract: In a golf ball having a core, a cover and a coating layer, the coating layer is formed of a urethane coating that includes an organic solvent having a boiling point of 80° C. or less, a silicone-based additive and, as a curing agent, a polyisocyanate which contains an adduct and an isocyanurate of hexamethylene diisocyanate. Although the golf ball includes a silicone-based additive in the outer surface (coating layer) of the ball, it has a good spin performance on approach shots not only when wet but also when normally dry, and is capable of exhibiting both a good water-repelling performance and a good friction performance.

Abstract: In a golf ball having a core of at least one layer and a cover of at least one layer encasing the core, at least one layer of the cover is formed of a resin composition which includes (I) a polyurethane or a polyurea, (II) a thermoplastic polyester elastomer and (III) an aromatic vinyl elastomer. The thermoplastic polyester elastomer serving as component (II) and the aromatic vinyl elastomer serving component (III) have specific respective contents and properties, including Shore D hardnesses and rebound resiliences. The golf ball has an excellent controllability on approach shots without a loss of distance on driver shots. In addition, the scuff resistance and moldability are good.

Abstract: In a golf ball having a core and a cover of one or more layer, at least one layer of the cover is formed of a resin composition which includes in a specific weight ratio: (I) a thermoplastic polyurethane resin that uses polytetramethylene glycol having a number-average molecular weight of from 1,900 to 2,100 as the polyol component, (II) a thermoplastic polyurethane resin that uses polytetramethylene glycol having a number-average molecular weight of from 900 to 1,100 as the polyol component, and (III) an aromatic vinyl elastomer. The cover layer formed of this resin composition has a Martens hardness and an elastic work recovery which together satisfy a specific formula. The golf ball has an excellent controllability on approach shots without losing distance on driver shots. In addition, the scuff resistance and moldability are good.

Abstract: In a golf ball having a core of at least one layer and a cover of one or more layer encasing the core, at least one layer of the cover is formed of a resin composition that includes (I) a polyurethane or a polyurea and (II) an aromatic vinyl elastomer which together satisfy certain specific conditions. The golf ball has an excellent controllability on approach shots and is also able to maintain a good scuff resistance.

Abstract: In a golf ball comprising a core, a cover layer, an intermediate layer between the core and the cover layer, the cover layer is formed of a resin material composed primarily of polyurethane or polyurea, a sphere obtained by encasing the core with the intermediate layer (intermediate layer-encased sphere) has a lightness (Li value) in the L*a*b* color space of at least 25 on its surface, and the cover layer has a visible light transmittance of at least 0.6%. The golf ball has a surface with a distinctive aesthetic appearance and retains both a good spin performance and a good scuff resistance, making it useful as a ball for professional and skilled amateur golfers.

Abstract: In a golf ball having a rubber core of at least one layer and a cover of at least one layer encasing the core, at least one layer of the cover is formed of a resin composition that includes (A) polyurethane or polyurea, and (B) a thermoplastic polyester elastomer. Component (B) is included in a ratio of not more than 45 wt % of the overall amount of the resin composition, and the resin composition has a Shore D hardness of 42 or less and a rebound resilience of from 60 to 72%. The golf ball has an excellent controllability on approach shots, is able to maintain a good feel at impact and a good scuff resistance, and also has a good moldability.

Abstract: In a golf ball having a rubber core of at least one layer and an inner cover layer and outer cover layer which encase the core, the inner cover layer is formed of a resin composition that includes (A) a polyurethane or polyurea and (B) a thermoplastic polyester elastomer, which resin composition has a Shore D hardness of 52 or less and a rebound resilience of at least 50%, and the outer cover layer is formed of a resin composition which includes a polyurethane or polyurea of the same type as component (A) or of a different type. This ball has an improved rebound, an optimal spin rate on approach shots and thus a good controllability, and an excellent durability.

Abstract: A resin composition for golf balls is made of (A) polyurethane or polyurea and (B) a styrene resin material, component (B) being included in an amount of 0.5 to 50 parts by weight per 100 parts by weight of component (A). In a golf ball having a core and a cover of one or more layer encasing the core, at least one cover layer is formed of this resin composition. The resin composition is especially useful as a golf ball cover material because the ball does not fly too far and is easier to control on approach shots, yet does not sacrifice distance on shots with a driver.

Abstract: A golf ball having a core and a cover that is formed of a resin composition which includes (A) a polyurethane or a polyurea and (B) a styrenic resin material, when dropped from a height of 3 m and made to collide with a metal plate, has velocities 200 ms before and 200 ms after contact that satisfy the condition: (incident velocity)?(rebound velocity)?0.80 m/s. The ball has a good controllability on approach shots without a loss in the distance achieved on shots with a driver, and thus is particularly useful to professional golfers and skilled amateurs.

Abstract: 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.

Abstract: In a golf ball having a core of at least one layer and a cover of one or more layer encasing the core, at least one layer of the cover is formed of a resin composition that includes (I) a polyurethane or a polyurea and (II) an aromatic vinyl elastomer which together satisfy certain specific conditions. The golf ball has an excellent controllability on approach shots and is also able to maintain a good scuff resistance.

Abstract: The invention provides a golf ball resin composition that includes (A) an aromatic vinyl elastomer and (B) a polyurethane or a polyurea, the amount of component (A) being 50 parts by weight or less per 100 parts by weight of component (B), and also provides a golf ball in which at least one cover layer is formed of this resin composition. The resin composition is particularly useful as a golf ball cover material because golf balls in which it is used do not fly too far and have a good controllability on approach shots, and moreover maintain a good scuff resistance and moldability without a loss of distance on shots with a driver.

Abstract: A resin composition for golf balls is made of (A) polyurethane or polyurea and (B) an acrylic resin or a methacrylic resin, component (B) being included in an amount of from 0.5 to 50 parts by weight per 100 parts by weight of component (A). In a golf ball having a core and a cover of one or more layer encasing the core, at least one cover layer is formed of this resin composition. The resin composition is especially useful as a golf ball cover material because it makes it possible to achieve a higher ball initial velocity on shots with a driver and a lower ball initial velocity on approach shots.

Abstract: In a golf ball having a core of at least one layer and a cover encasing the core, the cover is formed of a resin composition composed primarily of a polyurethane or a polyurea. Letting HMa (N/mm2) be the Martens hardness of the cover measured at a position 0.3 mm toward the center of the ball from the cover surface and ?Ita (%) be the elastic recovery of the cover, HMa and ?Ita satisfy the following conditions: (1) ?Ita??1.16×HMa+79, (2) 10.0?HMa?38.0, and (3) 40??Ita?80. The ball has an excellent spin performance on approach shots and an excellent scuff resistance.

Abstract: A golf ball having a core and a cover that is formed of a resin composition which includes (A) a polyurethane or a polyurea and (B) a styrenic resin material, when dropped from a height of 3 m and made to collide with a metal plate, has velocities 200 ms before and 200 ms after contact that satisfy the condition: (incident velocity)?(rebound velocity)?0.80 m/s. The ball has a good controllability on approach shots without a loss in the distance achieved on shots with a driver, and thus is particularly useful to professional golfers and skilled amateurs.

Abstract: 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.