Abstract: A golf ball which reduces the impact on the environment is provided. The golf ball, which may be a one-piece ball or a ball having a core and a cover of one or more layer, is composed at least in part of a biodegradable material.

Abstract: A golf ball material composed of (A) an oxygen-containing inorganic metal compound in the form of a particulate or a master batch capable of neutralizing at least some of the acid groups in an acid-containing polymer blend, (B) one or more polymer selected from among diene polymers, thermoplastic polymers and thermoset polymers, and (C) an acid-containing polymer is prepared by mixing component A in a blend of components B and C. The golf ball material has a good heat resistance, flowability and processability, and can be used to produce high-performance golf balls having durability, scuff resistance and optimal hardness without a loss of rebound.

Abstract: In a golf ball comprising a core and a cover, the cover is composed mainly of a blend of a soft ionomer in the form of a magnesium ion neutralized ethylene/(meth)acrylic acid/acrylate terpolymer and a hard ionomer in the form of a magnesium ion neutralized ethylene/(meth)acrylic acid copolymer. The blend has a Shore D hardness of 44-60. The ball is minimized in restitution loss and has an increased initial velocity, spin receptivity, good hitting feel, and scuff resistance.

Abstract: A solid golf ball includes a cover which is mainly formed from a resin blend of (a) 50-90% by weight of a salt of an ethylene-unsaturated carboxylic acid copolymer having an unsaturated carboxylic acid content of 10 to 20% by weight wherein at least 20 mol % of the carboxyl group is neutralized with a metal ion and (b) 50-10% by weight of an ethylene-unsaturated carboxylate-unsaturated carboxylic acid terpolymer having an unsaturated carboxylate content of 12 to 45% by weight and an unsaturated carboxylic acid content of 5.5 to 10% by weight. The cover has a hardness of 60 to 80 on JIS C hardness scale. The golf ball has many advantages including a pleasant feel, ease of spin, ease of control, high repulsion and resistance to peeling.

Abstract: In a golf ball comprising a core and a cover, the cover is mainly composed of a resin consisting of a first ionomer in the form of a sodium neutralized ethylene/methacrylic acid/acrylate terpolymer having a flexural modulus of 1,000 to 15,000 psi and a second ionomer in the form of a magnesium neutralized ethylene/methacrylic acid copolymer having a flexural modulus of 20,000 to 48,000 psi. The blend has a Shore C hardness of 65 to 77. The ball has a soft feel, satisfactory spin rate, improved scuff resistance upon iron shots, and durability against top hitting with an excellent compatibility in cover.

Abstract: A solid golf ball comprising a solid core and a cover has a multiplicity of dimples in its surface. The core undergoes a distortion of 2.8-4.0 mm under a load of 100 kg. The distortion (mm) of the core under a load of 100 kg divided by the distortion (mm) of the ball under a load of 100 kg is 1.0-1.3. The cover has a gage of 1.4-1.9 mm and a Shore D hardness of 53-60. Dimples of at least three types having different diameters are formed in the cover surface in a total number of 390-450. The diameter/depth ratio of each dimple is from 18/1 to 27/1. The volume of a dimple divided by the volume of a cylinder whose diameter and height correspond to the diameter and depth of the dimple, respectively, is 0.390-0.550. The golf ball is improved in flight distance, hitting feel and spin and will cover a distance even when hit at low head speeds.

Abstract: There is provided a golf ball comprising a core and a cover having a plurality of dimples thereon wherein said core has a distortion of 2.8 to 4.0 mm under a load of 100 kg, the ratio of a core distortion under a load of 100 kg divided by a ball distortion under a load of 100 kg ranges from 1.0 to 1.3, said cover has a thickness of 1.4 to 1.9 mm, and a Shore D hardness of 53 to 60, said dimples are divided into at least three kinds of dimples which have different diameters each other, each dimple has the ratio of diameter (mm) divided by depth (mm) of 18 to 27, the value of the spatial volume of each dimple below a plane defined by an edge of the dimple divided by the volume of a cylinder wherein the bottom of said cylinder is defined by said plane and the height is determined by the maximum depth of the dimple from said plane ranges from 0.390 to 0.550, and the total number of said dimples is in the range of 390 to 450.

Abstract: A golf ball cover is formed of a composition comprising (a) 70-95% by weight of a sodium or zinc salt of an ethylene-unsaturated carboxylic acid-unsaturated carboxylate terpolymer or a mixture thereof and (b) 30-5% by weight of a sodium or zinc salt of an ethylene-unsaturated carboxylic acid copolymer, an ethylene-unsaturated carboxylic acid-unsaturated carboxylate terpolymer or a mixture thereof, having an M.F.R. of at least 4, the composition curing into a product having a hardness of 55-80 on JIS C scale and a tensile stress at 10% distortion of 40-140 kg/cm.sup.2. The composition is easy to mold and allows for manufacture of a golf ball having improved spin properties and resistant to impact by iron and other clubs.

Abstract: A solid golf ball comprising a core and a cover is provided. The core has a core hardness expressed by a distortion of 2.2-4.0 mm under a load of 100 kg. The core hardness divided by the ball hardness ranges from 1.0 to 1.3. The cover has a thickness of 1.3-1.8 mm. The ball is improved in feel and spin while maintaining the flying distance inherent to solid golf balls.

Abstract: A golf ball cover is formed of a composition comprising (a) 70-95% by weight of a sodium or zinc salt of an ethylene-unsaturated carboxylic acid-unsaturated carboxylate terpolymer or a mixture thereof and (b) 30-5% by weight of a sodium or zinc salt of an ethylene-unsaturated carboxylic acid copolymer, an ethylene-unsaturated carboxylic acid-unsaturated carboxylate terpolymer or a mixture thereof, having an M.F.R. of at least 4, the composition curing into a product having a hardness of 55-80 on JIS C scale and a tensile stress at 10% distortion of 40-140 kg/cm.sup.2. The composition is easy to mold and allows for manufacture of a golf ball having improved spin properties and resistant to impact by iron and other clubs.

Abstract: In a golf ball comprising a cover enclosing a core, the cover is formed of a resin blend of (a) a potassium ionomer resin and (b) a magnesium ionomer resin. Both the ionomer resins are ethylene-.alpha., .beta.-unsaturated carboxylic acid copolymers containing 10 to 20% by weight of .alpha., .beta.-unsaturated carboxylic acid, 20 to 70 mol % of the carboxyl group being neutralized with potassium or magnesium ion. The ionomer resins have a melt index of 0.6 to 8 and a Shore D hardness of 55 to 70. Ionomer resins (a) and (b) are blended in a weight ratio of from 85:15 to 20:80. The cover has enhanced durability against hitting at no expense of repulsion upon hitting.

Abstract: A solid golf ball includes a solid core enclosed in a cover. The resin component of the cover consists of 30 to 100% by weight of an ethylene-methacrylic acid-acrylate terpolymer ionomer resin having a flexural modulus of 2,500-14,000 psi and a Shore D hardness of 20-59 and 70 to 0% by weight of an ethylene-(meth)acrylic acid copolymer ionomer resin having a flexural modulus of 20,000-29,000 psi and a Shore D hardness of 56-62. The ball is excellent in spin receptivity, burring resistance, and feel on hitting.

Abstract: In a golf ball comprising a cover around a core, the cover is formed of a resin blend of 10-60 parts by weight of a thermoplastic elastomer having a crystalline polyethylene block and 90-40 parts by weight of an ionomer resin. The ball is well controllable, highly repulsive, and resistant to scuffing upon iron shots and offers pleasant hitting feel.

Abstract: A three-piece solid golf ball comprising; a center core, an intermediate layer, and a cover enclosing the core through the intermediate layer,said center core formed of a polybutadiene base rubber and having a diameter of at least 26 mm, a specific gravity of less than 1.4, and a hardness up to 80 on JIS C scale,said intermediate layer formed of a thermoplastic polyester elastomer and having a thickness of at least 1 mm, a specific gravity of less than 1.2, and a hardness of less than 80 on JIS C scale, andsaid cover having a thickness of 1 to 3 mm, and a hardness of at least 85 on JIS C scale.

Abstract: A three-piece solid golf ball comprising a center core, an intermediate layer, and a cover. The center core (1) has a diameter of at least 29 mm, a hardness in the range of 45-80 JIS C and a specific gravity of less than 1.4. The intermediate layer (2) has a thickness of at least 1 mm, a specific gravity of less than 1.2, and a hardness of at least 85 on JIS C scale. The cover (3) has a thickness of 1-3 mm and a hardness of 50-85 JIS C. The ball has a good total balance of properties in that feeling and controllability are improved at no sacrifice of flying performance and durability.

Abstract: A golf ball comprising a core and a cover enclosing the core, the hardness of said core divided by the hardness of the ball being 1.00 to 1.20 wherein the core hardness and ball hardness are distortions measured in mm of the core and ball under a load of 100 kg. The cover is a one-layer construction, has a thickness of 1.85 to 2.35 mm, consists essentially of an ionomer resin, and has a shore D hardness of up to 60.

Abstract: A multi-piece solid golf ball has a solid core of multi-layer configuration including an inner layer circumscribed by an outer layer. The core inner layer is formed from a rubber composition. The core outer layer is formed thereon by injection molding a mixture of 100-50 wt % of a polyether ester type thermoplastic elastomer having a Shore D hardness of 30-50 and a Tg of up to -25.degree. C. and 0-50 wt % of an ethylene-(meth)acrylate copolymer ionomer having a flexural modulus of 200-400 MPa. The core is surrounded by a cover of an ethylene-(meth)acrylate copolymer ionomer having a flexural modulus of 200-450 MPa and a Shore D hardness of 55-68. The ball shows improved flying performance, feel on impact and durability and lends itself to mass production.

Abstract: One-piece and multi-layered golf balls are improved in flying performance by forming the one-piece ball entirely or multi-layered golf ball core from a rubber composition comprising a base rubber, an unsaturated carboxylic acid metal salt, and an organic sulfur compound and/or a metal salt thereof.

Abstract: Solid golf balls comprise a vulcanizable rubber and a reinforcing filler comprising an essentially anhydrous metal salt of an .alpha.,.beta.-ethylenically unsaturated carboxylic acid. Golf balls containing such reinforcing fillers have improved physical properties over rubber compounds containing conventional metal carboxylic acid salts. Additionally, the rubber compounds have improved processability and shorter curing time.

Abstract: One-piece and multi-layered golf balls are improved in flying performance by forming the one-piece ball entirely or multi-layered golf ball core from a rubber composition comprising a base rubber and a co-crosslinking agent in the form of a premix of an unsaturated fatty acid metal salt and a liquid polymer.