Abstract: A golf ball comprises a solid core consisting of a center core and an outer core, wherein at least one of cores is made of a rubber composition comprising 100 parts by weight of a base rubber including. 60 to 100% by weight of a polybutadiene containing at least 60% by weight of cis-1,4-bond, having a Mooney viscosity (ML1+4 (100° C.)) of at least 52, and synthesized using a rare-earth catalyst, 10 to 60 parts by weight of an unsaturated carboxylic acid and/or a metal salt thereof, 5 to 80 parts by weight of an-inorganic filler, and an organic peroxide, and wherein the center core has a JIS-C hardness of 40 to 60 on its center and a JIS-C hardness of 55 to 75 on its surface and the difference therebetween is at least 10, the outer core is harder than the surface hardness of the center core, the cross-sectional hardness of 1 mm outside from the border between the center core and the outer core is from 65 to 85 on a JIS-C hardness, the surface of the outer core has a JIS-C hardness of 75 to 95.

Abstract: Provided is a method of manufacturing compound single crystals by epitaxially growing a compound single crystal layer differing from the substrate in which the planar defects generated in the crystal that is epitaxially grown are reduced. The method of manufacturing compound single crystals in which a compound single crystalline layer differing from a compound single crystalline substrate is epitaxially grown on the surface of said substrate. Plural undulations extending in a single direction are present on at least a portion of the surface of said substrate, and in that said undulations are provided in such a manner that as said compound single crystalline layer grows, the defects that grow meet each other.

Abstract: The invention provides a golf ball comprising a core and a cover of one or more layers, characterized in that at least one layer which constitutes the cover is formed primarily of a mixture of (A) a thermoplastic resin composition selected from among a thermoplastic block copolymer, polyester base elastomer, polyamide base elastomer and polyolefin, which are modified with functional groups having reactivity with isocyanate, and (B) an isocyanate compound or an isocyanate mixture having at least two isocyanate groups as functional groups in a molecule, and a method for preparing the same. The golf ball has excellent flight performance, feel on impact, and scuff resistance.

Abstract: The invention provides a multi-piece solid golf ball comprising a core, an outermost layer cover, and at least one intermediate layer disposed therebetween, characterized in that the intermediate layer is formed of a resin composition having organic short fibers compounded therein. The golf ball has excellent flight performance and controllability in favor of professional and skilled golfers having high head speeds, and is improved in durability to repeated impact.

Abstract: In a golf ball comprising a core and a cover of one or more layers, at least one layer of the cover is formed primarily of a mixture comprising (A) an ionomer resin, (B) a thermoplastic elastomer and (C) a thermoplastic block copolymer terminated with a functional group capable of reacting with the ionomer resin, in such a proportion as to provide a A/(B+C) weight ratio between 50/50 and 98/2 and a B/C weight ratio between 9/1 and 1/1. The golf ball has improved rebound, a soft feel upon impact, good durability and good moldability.

Abstract: The invention provides a golf ball comprising a core of at least one layer, a cover of at least one layer, and optionally an intermediate layer therebetween, characterized in that at least one layer of the core, cover and intermediate layer is formed of a golf ball-forming resin composition comprising, in admixture, (A) 100 parts by weight of a polyether ester block copolymer composed primarily of (a) high-melting crystalline polymer segments made of crystalline aromatic polyester units and (b) low-melting polymer segments made of aliphatic polyether units and (B) 0.05–10 parts by weight of a polyisocyanate compound. Using the golf ball-forming resin composition which has flexibility and high rebound resilience and is fully wear resistant, the inventive golf ball is improved in travel distance, feel, scuff resistance and impact durability.

Abstract: A golf ball comprising a core and a cover formed of a cover resin composition is characterized in that the core has a hardness corresponding to a compressive deflection amount of at least 3.5 mm when the load applied thereto is increased from an initial load of 10 kgf to a final load of 130 kgf, the cover resin composition has a melt flow rate of at least 3 as measured according to JIS K7210, and the cover has a gage of up to 1.7 mm. The golf ball has a soft feel, offers superior flight performance to even those golf players with a low head speed of 35 m/s or less, and is improved in durability to repeated impact and moldability.

Abstract: A golf ball is characterized by comprising a molded and vulcanized product of a rubber composition as a constituent component, the rubber composition comprising 100 pbw of a base rubber including 60–100 wt % of a polybutadiene containing at least 60 wt % of cis-1,4-bond, having a Mooney viscosity (ML1+4 (100° C.)) of at least 40, and synthesized using a rare-earth catalyst, 10–60 pbw of an unsaturated carboxylic acid and/or a metal salt thereof, 0.1–5 pbw of an organosulfur compound, 5–80 pbw of an inorganic filler, and at least two organic peroxides including an organic peroxide having the shortest half-life at 155° C. designated (a) and another organic peroxide having the longest half-life at 155° C. designated (b), a ratio of half-lives (bt/at) being from 7 to 20 wherein at is the half-life of (a) and bt is the half-life of (b), a total content of the organic peroxides being 0.1–0.8 pbw per 100 pbw of the base rubber.

Abstract: A golf ball is manufactured by molding and vulcanizing a rubber composition comprising 100 pbw of a base rubber composed primarily of a polybutadiene having a cis-1,4 content of at least 60 wt % and a Mooney viscosity of at least 30 and synthesized using a rare-earth catalyst, 15–50 pbw of an unsaturated carboxylic acid and/or a metal salt thereof, at least 2 pbw of a processing aid having a highest melting point of up to 115° C., and 1–5 pbw of an organic peroxide. The golf ball can be efficiently manufactured and has excellent rebound characteristics.

Abstract: Disclosed herein is a solid golf ball made up of a core and at least one cover, wherein said core is formed mainly from a polybutadiene which is synthesized with using a catalyst of rare earth element such that the content of cis-1,4 bond is no less than 60%, said core has a diameter of 34.7 to 42.0 mm, said core undergoes deflection amounting to 2.5 to 5.0 mm under a load of 100 kg, said cover has an outermost cover layer which is formed mainly from a thermoplastic resin or elastomer compounded with organic short fibers, said outermost cover layer has a Shore D hardness of 55 to 70 and a thickness of 0.5 to 2.0 mm, and said ball weighs 40.0 to 44.9 g. The solid golf ball excels in both flying performance and crack resistance and permits novice golfers to increase flying distance even when it is hit with a low head speed.

Abstract: Disclosed herein is a multi-piece golf ball composed of a core and an outermost cover layer, with one or more inner cover layers interposed between them, which is characterized in that the core is made mainly of a polybutadiene which is synthesized with using a catalyst of rare earth element such that the content of cis-1,4 bond is no less than 60%, the core has a diameter of 34.7 to 40.7 mm, the core undergoes deflection amounting to 3.0 to 5.0 mm under a load of 100 kg, the outermost cover layer is formed mainly of a thermoplastic resin or elastomer compounded with organic short fibers, the outermost cover layer has a Shore D hardness of 55 to 70 and a thickness of 0.5 to 2.0 mm, and the inner cover layer has a Shore D hardness of 15 to 55 and a thickness of 0.5 to 2.0 mm. The multi-piece golf ball exhibits good flying performance and crack durability. In addition, it gives the player a good striking feel at the time of putting and driver shot.

Abstract: A golf ball comprising a core and two or more outer layers covering said core, wherein the first outer layer is formed mainly from a mixture of a non-ionomer thermoplastic elastomer and an isocyanate compound and the second outer layer is formed mainly from a mixture composed of a resin component consisting of an ionomer resin and a non-ionomer thermoplastic elastomer, a fatty acid and/or a derivative thereof, a metal ion source capable of neutralizing unneutralized acid radicals in the above-mentioned components, and a compound having two or more reactive functional groups and a molecular weight no larger than 20,000, with the first outer layer being contiguous to the second outer layer, which exhibits superior in durability and rebound resilience.

Abstract: Disclosed herein is a solid golf ball made up of a core and at least one cover, wherein said core is formed mainly from a polybutadiene which is synthesized with using a catalyst of rare earth element such that the content of cis-1,4 bond is no less than 60%, said core has a diameter of 34.7 to 42.0 mm, said core undergoes deflection amounting to 2.5 to 5.0 mm under a load of 100 kg, said cover has an outermost cover layer which is formed mainly from a thermoplastic resin or elastomer compounded with organic short fibers, said outermost cover layer has a Shore D hardness of 55 to 70 and a thickness of 0.5 to 2.0 mm, and said ball weighs 40.0 to 44.9 g. The solid golf ball excels in both flying performance and crack resistance and permits novice golfers to increase flying distance even when it is hit with a low head speed.

Abstract: Disclosed herein is a multi-piece golf ball composed of a core and an outermost cover layer, with one or more inner cover layers interposed between them, which is characterized in that the core is made mainly of a polybutadiene which is synthesized with using a catalyst of rare earth element such that the content of cis-1,4 bond is no less than 60%, the core has a diameter of 34.7 to 40.7 mm, the core undergoes deflection amounting to 3.0 to 5.0 mm under a load of 100 kg, the outermost cover layer is formed mainly of a thermoplastic resin or elastomer compounded with organic short fibers, the outermost cover layer has a Shore D hardness of 55 to 70 and a thickness of 0.5 to 2.0 mm, and the inner cover layer has a Shore D hardness of 15 to 55 and a thickness of 0.5 to 2.0 mm. The multi-piece golf ball exhibits good flying performance and crack durability. In addition, it gives the player a good striking feel at the time of putting and driver shot.

Abstract: A golf ball comprising a core and a multilayer cover including at least a cover inner layer and a cover outer layer is characterized in that the core has a hardness corresponding to a compressive deflection amount of at least 3.5 mm when the load applied thereto is increased from an initial load of 10 kgf to a final load of 130 kgf, the cover outer layer is made of a resin composition having organic short fibers incorporated therein, the resin composition has a melt flow rate of at least 3 as measured according to JIS K7210, the cover outer layer has a Shore D hardness of at least 55 and is harder than the cover inner layer, and the cover outer layer has a gage of up to 1.4 mm. The golf ball has a soft feel, offers superior flight performance to even those golf players with a low head speed of 35 m/s or less, and is improved in durability to repeated impact and moldability.

Abstract: The invention provides a golf ball comprising a core of at least one layer, a cover of at least one layer, and optionally an intermediate layer therebetween, characterized in that at least one layer of the core, cover and intermediate layer is formed of a golf ball-forming resin composition comprising (A) 50–95% by weight of a polyether ester block copolymer composed primarily of (a) high-melting crystalline polymer segments made of crystalline aromatic polyester units and (b) low-melting polymer segments made of aliphatic polyether units and (B) 5–50% by weight of a thermoplastic polyurethane elastomer, the total of components (A) and (B) being 100 parts by weight, in admixture with (C) 0.05–10 parts by weight of a polyisocyanate compound. The inventive golf ball is improved in travel distance, feel, scuff resistance and impact durability.

Abstract: In a golf ball comprising a core and a cover of at least two layers, a cover outermost layer is formed of a composition comprising 100 pbw of a thermoplastic resin and 0.2–5 pbw of a cholesteric liquid crystal polymer, and a cover inner layer is formed of a composition comprising 100 pbw of a thermoplastic resin, 0.1–1 pbw of titanium oxide, and 0.05–1 pbw of a fluorescent pigment. The golf ball has an outer appearance whose color continuously changes with the viewing angle, a brilliance, a good color harmony over the entire ball, improved spin performance, and scuff resistance.

Abstract: The invention provides a golf ball comprising a core of at least one layer, a cover of at least one layer, and optionally an intermediate layer therebetween, characterized in that at least one layer of the core, cover and intermediate layer is formed of a golf ball-forming resin composition comprising (A) 50-95% by weight of a polyether ester block copolymer composed primarily of (a) high-melting crystalline polymer segments made of crystalline aromatic polyester units and (b) low-melting polymer segments made of aliphatic polyether units and (B) 5-50% by weight of a thermoplastic polyurethane elastomer, the total of components (A) and (B) being 100 parts by weight, in admixture with (C) 0.05-10 parts by weight of a polyisocyanate compound. The inventive golf ball is improved in travel distance, feel, scuff resistance and impact durability.

Abstract: The invention provides a golf ball comprising a core of at least one layer, a cover of at least one layer, and optionally an intermediate layer therebetween, characterized in that at least one layer of the core, cover and intermediate layer is formed of a golf ball-forming resin composition comprising, in admixture, (A) 100 parts by weight of a polyether ester block copolymer composed primarily of (a) high-melting crystalline polymer segments made of crystalline aromatic polyester units and (b) low-melting polymer segments made of aliphatic polyether units and (B) 0.05-10 parts by weight of a polyisocyanate compound. Using the golf ball-forming resin composition which has flexibility and high rebound resilience and is fully wear resistant, the inventive golf ball is improved in travel distance, feel, scuff resistance and impact durability.

Abstract: The invention provides a multi-piece solid golf ball comprising a core, an outermost layer cover, and at least one intermediate layer disposed therebetween, characterized in that the intermediate layer is formed of a resin composition having organic short fibers compounded therein. The golf ball has excellent flight performance and controllability in favor of professional and skilled golfers having high head speeds, and is improved in durability to repeated impact.