Abstract: The present invention provides a multi-piece solid golf ball, of which flight distance is improved by accomplishing high launch angle and low spin amount, when hit by golfers, who swing a golf club at low head speed, using a middle iron club to a driver. The present invention relates to multi-piece solid golf ball comprising a center, an intermediate layer formed on the center and a cover covering the intermediate layer, wherein the intermediate layer is formed from only one material having a flexural stiffness of 400 to 5,000 MPa.

Abstract: The present invention provides a golf ball having excellent shot feel, controllability, rebound characteristics, scuff resistance, yellowing resistance and productivity. The present invention relates to a golf ball comprising a core and a cover covering the core, wherein the cover comprises polyurethane-based thermoplastic elastomer formed by using cycloaliphatic diisocyanate as a base resin.

Abstract: The present invention provides a three-piece solid golf ball having excellent shot feel, controllability, rebound characteristics, scuff resistance, yellowing resistance and productivity. The present invention relates to a three-piece solid golf ball comprising a core composed of a center and an intermediate layer formed on the center, and a cover formed on the core, wherein the cover comprises a mixture of polyurethane-based thermoplastic elastomer and polyamide-based thermoplastic elastomer as a base resin.

Abstract: A method of producing a golf ball with uniform thickness by, eliminating defective air between the cover and the core, an insufficient thickness of the cover and an uneven thickness of the cover wherein in the step of heat and compression molding to cover the core or an intermediate layer with shells molded from a cover material mainly composed of a thermoplastic resin, if the mold has a temperature of T1° C. and the half shells start to flow at a temperature of T2° C., T1 minus T2 is set within a range of ?3° C. to +10° C.

Abstract: There is provided a method of producing a golf ball, capable of forming a cover to have a uniform thickness to produce a golf ball excellent in resistance to abrasion. The method includes a step to subject a cover material mainly composed of a thermoplastic resin to heat and compression molding to form a half shell, and a step to allow two such half shells to be arranged on a core or an intermediate layer, joined together, and heat and compression molded to mold the cover to have a thickness of 0.3 to 1.5 mm.

Abstract: A golf ball excellent in wear resistance and abrasion resistance is provided without sacrificing various characteristics such as rebound performance, spin performance, cut resistance and feeling at the time of hitting. The golf ball is formed of a core and a cover covering the core. The cover is formed by mixing 1–50 parts by mass of a ternary composite made of a rubber component, a polyolefin component and a nylon component in 100 parts by mass of at least one resin component selected from the group consisting of a polyurethane resin, a polyester resin, a polyamide resin and an olefin resin.

Abstract: The invention provides a multi-piece solid golf ball having soft, good shot feel, excellent flight performance, high rebound characteristics and high launch angle, when hit by golfers who swing a golf club at high or low head speed using all golf clubs, namely, a driver to an iron club, a putter. The multi-piece solid golf ball has a core having an inner core and an outer core covering the inner core, and at least one layer covering the core; the inner core has a diameter of 30 to 40.4 mm and surface hardness of 60 to 85 JIS-C, and center JIS-C hardness of the inner core lower than the surface hardness by 5 to 30; the outer core has a thickness of 0.2 to 1.3 mm, and a surface JIS-C hardness of the outer core lower than the surface hardness of the inner core by 2 to 30.

Abstract: The present invention provides a multi-piece solid golf ball, of which durability is excellent and flight distance is improved by accomplishing high launch angle and low spin amount, when hit by golfers, who swing a golf club at low head speed, using a middle iron club to a driver. The present invention relates to a multi-piece solid golf ball comprising a center, an intermediate layer formed on the center and a cover covering the intermediate layer, wherein the intermediate layer is formed from a material having an elongation of 9 to 20 mm when applying the maximum load in penetration and impact fatigue tests and a flexural stiffness of 300 to 2,000 MPa.

Abstract: The present invention provides a golf ball having excellent scuff resistance. The present invention relates to a golf ball comprising at least one layer of a core and a cover covering the core, wherein the cover is formed from a material having a value of the maximum load of 1.5 to 3.0 kN at an impact energy of 47.3 J in penetration and impact fatigue tests.

Abstract: A golf ball 2 has a core 4, a cover 6, and numerous dimples 8. This cover 6 is composed of a resin composition which includes a thermoplastic styrene elastomer and an ionomer resin as principle components. A melt index of this resin composition at 190° C. is equal to or greater than 4.0 g/10 min. Ratio R1 of the diameter dmax of the maximum dimple to the diameter D of the golf ball 2 is 10.5% or greater and 17.0% or less. A ratio R2 of the number of dimples 8 having a diameter d accounting for 10.5% or greater and 17.0% or less of the diameter D of the golf ball 2, occupied in total number N of the dimples is equal to or greater than 20%. Shore D hardness of the cover 6 is 50 or greater and 63 or less.

Abstract: A solid golf ball with a polyurethane cover having satisfactory formability and ball properties. The solid golf ball has a solid core, and a polyurethane cover for covering the solid core, wherein the difference in Shore D hardness between a center portion and a surface portion of the solid core is at least 15; the polyurethane cover has a thickness (t) of not more than 1.0 mm, and is formed from a cured urethane composition having Shore D hardness (D) of from 35 to 60; a product of the thickness(t) and the Shore D Hardness (D) of the cured urethane composition is ranging from 10 to 45(10?D×t?45); and the urethane composition contains an isocyanate group-terminated urethane prepolymer having the residual polyisocyanate monomer content of not more than 0.1 mass %, and an aromatic polyamine compound.

Abstract: A golf ball, which is superior in rebound characteristics, spin performance, scuff resistance, yellowing resistance and productivity, and has good moldability including a core and a cover formed on the core, wherein the cover includes a mixture (c) of a component (a) and a component b) as a base resin, wherein the elastic modulus of each component satisfies a relationship represented by the following formula: EaX+EbY>Ec (wherein, Ea, Eb and Ec represent the elastic modulus of component (a), component (b) and mixture (c), respectively, and X and Y represent a formulation ratio of the component (a) and component (b)).

Abstract: The present invention provides a golf ball, which is superior in rebound characteristics, flight distance and scuff resistance. The present invention relates to a golf ball comprising at least one layer of a core and a cover formed on the core, wherein the cover is formed from a cover resin composition mainly comprising a mixture of (a) polyurethane-based thermoplastic elastomer, and (b) a functional group modified polyester-based thermoplastic elastomer as a base resin.

Abstract: A golf ball 2 has a core 4, a cover 6, and numerous dimples 8. This cover 6 is composed of a resin composition which includes a thermoplastic styrene elastomer and an ionomer resin as principle components. A melt index of this resin composition at 190° C. is equal to or greater than 4.0 g/10 min. Ratio R1 of the diameter dmax of the maximum dimple to the diameter D of the golf ball 2 is 10.5% or greater and 17.0% or less. A ratio R2 of the number of dimples 8 having a diameter d accounting for 10.5% or greater and 17.0% or less of the diameter D of the golf ball 2, occupied in total number N of the dimples is equal to or greater than 20%. Shore D hardness of the cover 6 is 50 or greater and 63 or less.

Abstract: A golf ball providing rebound performance, spin performance, resistance to abrasion and anti-wearability in an excellent balance is formed of a core and a cover arranged to cover the core and formed mainly of diene rubber having a smaller trans structure content before it is crosslinked than after it is crosslinked, in particular by 2 to 20%. The diene rubber is preferably polybutadiene rubber and as the cover's co-crosslinking agent a metallic salt of ?,?-ethylene unsaturated carboxylic acid is used.

Abstract: The present invention provides a golf ball, which is superior in shot feel, rebound characteristics and laminar separation resistance. The present invention relates to a golf ball comprising at least one layer of a core and a cover formed on the core, wherein the cover is formed from a cover resin composition mainly comprising a mixture of (a) ionomer resin, and (b) a functional group modified polyester-based thermoplastic elastomer as a base resin.

Abstract: A golf ball formed of multiple layers that allows limiting an uplifting trajectory, providing a trajectory in which the height of the golf ball is well retained in the latter half of the flight of the ball thereby increasing travel distance, where at least one layer is made of a composition of a ternary copolymer ionomer, a higher fatty acid and an inorganic metal compound mixed together, at least 80% of the carboxyl group contained in the composition is neutralized, and the total volume of the dimples (Dv) on the cover surface ranges from 495 to 575 mm3. The above composition is suitable for the cover. The higher fatty acid is a fatty acid with 12 to 40 carbon atoms, and preferably is stearic acid or oleic acid.

Abstract: A golf ball providing resistance to abrasion and resistance to wear generally in an excellent balance is formed of a core and a cover arranged to cover the core, the cover being formed of a compound containing relative to 100 parts by mass of a polymer component thereof composed mainly of polybutadiene rubber 1-40 parts by mass of a reinforcement material formed of organic short fiber and 10-40 parts by mass of a metallic salt of ?,?-ethylene unsaturated carboxylic acid. It is characterized in that the organic short fiber is suitably a ternary composite formed of a rubber component, a polyolefin component and a nylon component and the metallic salt of ?,?-ethylene unsaturated carboxylic acid is suitably zinc acrylate, zinc methacrylate, magnesium acrylate or magnesium methacrylate.

Abstract: Golf ball 1 has a core 2 and a cover 3. The cover 3 is formed from a polymer composition. A coefficient of loss at ?20° C., T(?20), and a complex elastic modulus at ?20° C., E(?20) Kgf/cm2, of this polymer composition satisfy the following mathematical formula (I): T(?20)?4.2*10?5*E(?20)?0.24 ??(I). The coefficient of loss T(?20) is equal to or greater than 0.05 and equal to or less than 0.50, and particularly equal to or greater than 0.05 and equal to or less than 0.40. The complex elastic modulus E(?20) is equal to or greater than 500, and particularly equal to or greater than 1000. The thickness of the cover is equal to or greater than 0.3 mm and equal to or less than 1.4 mm, and particularly equal to or greater than 0.3 mm and equal to or less than 1.0 mm.

Abstract: The present invention provides a multi-piece solid golf ball, which is superior in rebound characteristics and flight performance, while maintaining good productivity. The present invention relates to a multi-piece solid golf ball comprising a core, an intermediate layer formed on the core and a cover covering the intermediate layer, wherein the intermediate layer is formed from an intermediate layer composition comprising a functional group modified resin as a main component, the cover is formed from a cover composition comprising a resin having polar site that can react with the functional group of the functional group modified resin in the intermediate layer as a main component, and a hardness of the intermediate layer is higher than that of the cover.