Abstract: In the present invention, by optimizing the balance of Shore D hardness between the intermediate layer and the cover, the balance of Shore D hardness between the surface and the center in the core, the balance of initial velocity between the core and the sphere, and the balance of Deflection amount between the core and the sphere are optimized, and the total thickness of the intermediate layer and the cover, the inventive golf ball is given a good profile of rebound, feel, controllability and durability.

Abstract: A golf ball comprising: (a) a core; (b) an inner mantle layer; (c) an intermediate mantle layer; (d) an outer mantle layer; and (e) at least one cover layer; wherein the core has a PGA compression of less than 70, and the core/inner mantle layer/intermediate mantle layer combined construct has a PGA compression of at least 30.

Abstract: A method of making a golf ball comprising the steps of providing an untreated golf ball core comprising a thermoset rubber composition, the untreated golf ball core comprising an untreated outer surface having a hardness; treating the untreated outer surface of the untreated golf ball core with a surface-softening material comprising at least one fatty acid or fatty acid salt composition to form a golf ball core comprising a treated outer surface having a hardness less than the hardness of the untreated outer surface; and forming at least one cover layer about the core to form the golf ball. Also, the untreated core may comprise a geometric center and an untreated outer surface, each having a hardness such that the hardness of the treated outer surface is less than both the hardness of the untreated geometric center and the hardness of the untreated outer surface.

Abstract: In a golf ball composed of a core and a cover having a plurality of layers that encloses the core, at least a first layer of the cover is formed primarily of a heated mixture of (A) a metal ion neutralization product of an olefin-unsaturated carboxylic acid copolymer and/or a metal ion neutralization product of an olefin-unsaturated carboxylic acid-unsaturated carboxylic acid ester copolymer, (B) at least one type of olefin-unsaturated carboxylic acid copolymer and/or olefin-unsaturated carboxylic acid-unsaturated carboxylic acid ester copolymer having the same content of unsaturated carboxylic acid as component A, and (C) a thermoplastic polyurethane elastomer; and at least one other cover layer adjoining the at least first cover layer is formed primarily of a non-ionomeric thermoplastic elastomer.

Abstract: A multilayer golf ball with at least one layer made from an expandable polymeric composition is disclosed. In accordance to one aspect of the invention, the expandable polymeric composition comprises a film-forming binder polymer latex, a dispersing agent, a plurality of polyspheres encapsulating expandable volatile substance, and at least one additive. The additive can be a defoaming agent, a solvent, a thickener, a plasticizer, or any combination thereof. Another expandable polymeric composition comprises a curable silicone composition comprising a liquid diorganopolysiloxane, a liquid organosilicon compound, a condensation catalyst and a blowing agent. Another the expandable polymeric composition comprises an aqueous acrylic based latex emulsion and an unencapsulated blowing agent.

Abstract: Disclosed herein is a multi-layer golf ball having a soft outer cover. The golf ball has an inner cover layer with a Shore D hardness of 60 or more, and an outer cover with a Shore D hardness of 55 or less, and more preferably 50 or less. In a particularly preferred form of the invention, the outer cover comprises one or more polyurethane materials. The golf ball of the invention has exceptionally soft feel and high spin rates on short shots of 80 yards or less, and particularly, 40 yards or less, while maintaining good distance and average spin on full shots.

Abstract: An all rubber golf ball with one or more thermosetting rubber core layers and one or more thermosetting rubber cover layer. At least one of the ball's layers has moisture vapor barrier property, and in one aspect the moisture vapor barrier layer is an intermediate layer. In one embodiment, the thermosetting rubber layers follow a cis- or a trans-polybutadiene gradient from the center of the ball to its cover.

Abstract: An ionomer modified by an amine-functionalized chemical for use in sporting equipment. The ionomer modified by an amine-functionalized chemical facilitates high COR, compression, durability, and ease of processing.

Abstract: This invention is directed to A composition for forming a golf ball, the composition comprising polyurethane gel composite particles and at least one base material selected from the group consisting of synthetic resins and elastomers, the polyurethane gel composite particles consisting of colloidal polyurea particles precipitated from a non-aqueous solvent solution of colloidal polyurea and polyurethane gel particles covered with the polyurea particles, the polyurethane gel particles being three-dimensionally crosslinked and each of the polyurethane gel particles being formed of a polyisocyanate compound and a polyethylene oxide group-free, active-hydrogen-containing compound, at least one of the compounds being trifunctional or higher valency, and is also directed to a multi-piece golf ball having one or more layers formed of this composition.

Abstract: A golf ball comprising a thermoplastic inner core layer that has a geometric center hardness greater than its surface hardness to define a “negative” hardness gradient. An outer core layer is disposed about the inner core and is formed from a substantially homogenous thermoset composition, typically rubber, and has an inner surface hardness substantially less than its outer surface hardness to define a “positive” hardness gradient. An inner cover layer is disposed about the outer core layer and an outer cover layer is disposed about the inner cover layer. The “negative” hardness gradient of the inner core is typically ?1 to ?5 Shore C and the “positive” hardness gradient of the core layer is typically at least 25 Shore C. The difference between the inner core surface hardness and the outer core inner surface hardness, ?h, should be at least 25 Shore C.

Abstract: A golf ball comprising a thermoplastic inner core layer that has a geometric center hardness greater than its surface hardness to define a “negative” hardness gradient. An outer core layer is disposed about the inner core and is formed from a substantially homogenous thermoset composition, typically rubber, and has an inner surface hardness less than its outer surface hardness to define a “positive” hardness gradient. An inner cover layer is disposed about the outer core layer and an outer cover layer is disposed about the inner cover layer. The “negative” hardness gradient of the inner core is typically ?1 to ?5 Shore C and the “positive” hardness gradient of the core layer is less than 25 Shore C points. The difference between the inner core surface hardness and the outer core inner surface hardness, ?h, should be less than 25 Shore C points.

Abstract: A golf ball comprising a thermoplastic inner core layer that has a geometric center hardness greater than its surface hardness to define a first “negative” hardness gradient. An outer core layer is disposed about the inner core and is formed from a substantially homogenous thermoset composition, typically rubber, and has an inner surface hardness greater than its outer surface hardness to also define a “negative” hardness gradient. An inner cover layer is disposed about the outer core layer and an outer cover layer is disposed about the inner cover layer. The “negative” hardness gradient of the inner core is typically ?1 to ?5 Shore C and the “negative” hardness gradient of the core layer is typically at least ?7 Shore C. The difference between the inner core surface hardness and the outer core inner surface hardness, ?h, should be at least ?3 Shore C.

Abstract: A golf ball comprising a thermoplastic inner core layer that has a geometric center hardness greater than its surface hardness to define a first “negative” hardness gradient. An outer core layer is disposed about the inner core and is formed from a substantially homogenous thermoset composition, typically rubber, and has an inner surface hardness greater than its outer surface hardness to also define a “negative” hardness gradient. An inner cover layer is disposed about the outer core layer and an outer cover layer is disposed about the inner cover layer. The “negative” hardness gradient of the inner core is typically ?1 to ?5 Shore C and the “negative” hardness gradient of the core layer is typically at least ?1 Shore C but less than ?7 Shore C. The difference between the inner core surface hardness and the outer core inner surface hardness, ?h, should be at least ?3 Shore C.

Abstract: A golf ball including a thermoplastic core having an outer diameter of 1.51 inches to 1.59 inches; an outer cover layer; and an inner cover layer between the core and the outer cover layer. The thermoplastic core has been exposed to a gradient-initiating solution comprising a solvent, free radical initiator, and a reactive co-agent comprising a metal salt of an acrylic or methacrylic acid, a mono- or multi-functional acrylate or methacrylate, or having the chemical structure where R=linear, branched, or aromatic C1-C14 and n=1-5, such that the hardness of the outer surface is different than the hardness of the geometric center to define a positive or negative hardness gradient of 5 Shore C or greater.

Abstract: The present invention relates to a golf ball having a core, a cover of at least one layer encasing the core, and a surface on which a plurality of dimples are formed. The cover has an outermost layer with a thickness of at least 1.2 mm and a Shore D hardness of at least 50 but not more than 65. The ball surface has a lightness L value, expressed in the Lab color system as defined by JIS Z8730, of at least 89, an a value of at least 2 but not more than 10, and a b value of ?20 or above. Increasing the reddish coloring of a white golf ball enhances the fashionability of the ball and improves the way the ball looks and feels to the golfer when it is played.

Abstract: The present invention relates to a golf ball having a ball component made of a material molded under heat from a rubber composition which includes: (A) at least 1 wt % but less than 30 wt % of a modified polybutadiene which is obtained by a modification reaction wherein a polybutadiene having a vinyl content of from 0 to 2%, a cis-1,4 bond content of at least 80% and an active end is modified at the active end with at least one type of alkoxysilane compound, and which has a Mooney viscosity of less than 40, and (B) at least 70 parts by weight of a diene rubber other than ingredient A. The rubber composition additionally includes the following per 100 parts by weight of ingredients A and B combined: (C) from 10 to 50 parts by weight of an unsaturated carboxylic acid and/or a metal salt thereof, (D) from 5 to 80 parts by weight of an inorganic filler, and (E) from 0.1 to 10 parts by weight of an organic peroxide.

Abstract: Disclosed are golf balls comprising cores or intermediate layers prepared from thermoplastic compositions having coefficients of restitution equal to or greater than 0.83 and PGA compressions greater than 100. Also disclosed is a composition comprising or prepared from (a) at least one aliphatic, mono-functional organic acid having from 16 to 20 carbon atoms, wherein the organic acid is unsaturated and linear; (b) an ethylene acid copolymer consisting essentially of copolymerized comonomers of ethylene and from 18 to 24 weight % of copolymerized comonomers of at least one C3 to C8 ?,? ethylenically unsaturated carboxylic acid, based on the total weight of the ethylene acid copolymer, having a melt index from about 200 to about 600 g/10 minutes; wherein the combined acid moieties of (a) and (b) are nominally neutralized to a level from about 120% to about 200%; and optionally (c) filler.

Abstract: The present invention provides a multi-piece solid golf ball having a core, an envelope layer encasing the core, an intermediate layer encasing the envelope layer, and a cover which encases the intermediate layer and has formed on a surface thereof a plurality of dimples. The core is formed primarily of a rubber material, the envelope layer and the intermediate layer are each formed primarily of the same or different resin materials, and the cover is formed primarily of a thermoplastic resin or a thermoplastic elastomer. The envelope layer, intermediate layer and cover have thicknesses which satisfy the condition: cover thickness<intermediate layer thickness<envelope layer thickness, and the condition: (cover thickness+intermediate layer thickness)<envelope layer thickness.

Abstract: The present invention provides a multi-piece solid golf ball having a core, an envelope layer encasing the core, an intermediate layer encasing the envelope layer, and a cover which encases the intermediate layer and has formed on a surface thereof a plurality of dimples. The core is composed overall of an inner layer and an outer layer which are each formed primarily of a rubber material, with the outer core layer being harder than the inner core layer. The envelope layer, intermediate layer and cover have respective thicknesses which satisfy the condition: cover thickness<intermediate layer thickness<envelope layer thickness, and have respective material hardnesses (Shore D hardness) which satisfy the condition: envelope layer material hardness<intermediate layer material hardness>cover material hardness. The golf ball has a lower spin rate on full shots with a driver, further increasing the distance traveled by the ball.

Abstract: The present invention provides a multi-piece solid golf ball having a core, an envelope encasing the core, an intermediate layer encasing the envelope, and a cover which encases the intermediate layer and has formed on a surface thereof a plurality of dimples. The envelope is composed of at least two layers. The core is formed primarily of a rubber material. The envelope, intermediate layer and cover are each formed primarily of the same or different resin materials. The envelope layers and the intermediate layer have a combined thickness which is at least 5.0 times thicker than the cover. An optimized surface hardness relationship exists between the core, a Sphere I composed of the core encased by the envelope layers, a Sphere II composed of the core encased by the envelope layers and the intermediate layer, and a Sphere III composed of the core encased by the envelope layers, the intermediate layer and the cover.

Abstract: The present invention provides a multi-piece solid golf ball having a core, an envelope layer encasing the core, an intermediate layer encasing the envelope layer, and a cover which encases the intermediate layer and has formed on a surface thereof a plurality of dimples. The core is composed overall of an inner layer and an outer layer which are each formed primarily of a rubber material, with the outer core layer being harder than the inner core layer. The envelope layer, intermediate layer and cover have respective thicknesses which satisfy the condition: cover thickness<intermediate layer thickness<envelope layer thickness, and have respective material hardnesses (Shore D hardness) which satisfy the condition: envelope layer material hardness<intermediate layer material hardness>cover material hardness. The golf ball has a lower spin rate on full shots with a driver, further increasing the distance traveled by the ball.

Abstract: The present invention provides a three-piece solid golf ball having a core molded under heat from a specific rubber composition and inner and outer cover layers encasing the core. By optimizing the core deflection under a specific load and the overall thickness of the cover layers, by forming the inner cover layer of a highly neutralized ionomer resin composition, and by optimizing within specific ranges the Shore D hardnesses of the inner cover layer and the outer cover layer, the spin rate of the ball on shots with a driver can be sufficiently reduced, enabling an increased distance to be achieved.

Abstract: Compositions for golf balls including oxirane functional endcapped polymers and, in particular, compositions formed from polyurethane-based or polyurea-based prepolymers that are endcapped with an oxirane functional group. The oxirane functionality is opened with a suitable curing agent to provide a composition that has flexibility via the prepolymer backbone and stiffness via the oxirane functional endcaps.

Abstract: A three-piece solid golf ball having a solid core, an intermediate layer enclosing the solid core, and a cover layer enclosing the intermediate layer and having a large number of dimples formed in its surface, characterized in that the core deforms as much as 2.6 to 3.2 mm under a load which changes from 10 kg to 130 kg, the cover layer is formed mainly from thermoplastic polyurethane such that it has a lower hardness than the intermediate layer, a surface hardness of the cover layer being 58 to 64 in terms of Shore D hardness, with the difference in hardness between the cover layer and the intermediate layer being 4 to 10 in terms of Shore D hardness, the intermediate layer and the cover layer have a total thickness of 2.2 to 3.0 mm, the cover layer has a thickness of 0.8 to 1.3 mm, and the dimples have at least four different diameters and/or depths, with the average depth being 0.125 to 0.150 mm, and amount to 250 to 390 in all.

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: A multi-piece solid golf ball comprises a core having a structure consisting of at least two layers and a cover on the core consisting of outer and inner cover layers. The core has a diameter in the range of 35 to 41 mm. The inner sphere of the core is formed of a rubber material based on polybutadiene and an outer layer is formed of a thermoplastic or rubber based material. The outer cover layer has a Shore D hardness of up to 53 degrees and lower than that of the outer cover layer. The ball's carry is comparable to conventional solid golf balls and spin receptivity is approximate to wound golf balls while the ball is durable and offers pleasant feel.

Abstract: The invention provides a solid golf ball having a solid core and a cover layer that encases the core and has an outermost layer on an outside surface of which are formed a plurality of dimples. The solid core is formed of a rubber composition composed of 100 parts by weight of a base rubber that includes from 60 to 100 parts by weight of a polybutadiene rubber having a cis-1,4 bond content of at least 60% and synthesized using a rare-earth catalyst, from 0.1 to 5 parts by weight of an organosulfur compound, an unsaturated carboxylic acid or a metal salt thereof, an inorganic filler, and an antioxidant. The solid core has a deformation, when compressed under a final load of 130 kgf from an initial load of 10 kgf, of from 2.0 to 4.0 mm, and has a specific hardness distribution. The cover layer has a thickness of from 0.5 to 1.9 mm, and a Shore D hardness at the surface of from 50 to 70.

Abstract: Disclosed herein is a multi-layer golf ball having a soft outer cover. The golf ball has an inner cover layer with a Shore D hardness of 60 or more, and an outer cover with a Shore D hardness of 55 or less, and more preferably 50 or less. In a particularly preferred form of the invention, the outer cover comprises one or more polyurethane materials. The golf ball of the invention has exceptionally soft feel and high spin rates on short shots of 80 yards or less, and particularly, 40 yards or less, while maintaining good distance and average spin on full shots.

Abstract: The present invention is directed to an improved golf ball displaying the desired spin profile and having a generally rigid, thermoset polybutadiene outer core surrounding a relatively soft, low compression inner core. In general, this golf ball has an inner core and at least one outer core layer surrounding the inner core. The inner core has a hardness less than a hardness of the outer core and a specific gravity less than or equal to the outer core specific gravity. Overall the inner core compression and outer core are formulated to provide a combined overall core compression of greater than about 50, preferably greater than about 70. A cover layer is provided to surround and to cover the outer core layer.

Abstract: A golf ball composition having a copolymer with an acid content modified by a nucleating agent is described. The nucleating agent modifies the flexural modulus of the acid copolymer.

Abstract: A golf ball which is formed from a vulcanized rubber compound composed of 100 parts by weight of a rubber base material, 10 to 60 parts by weight of an unsaturated carboxylic acid and/or a metal salt thereof, 0.1 to 5 parts by weight of an organosulfur compound, 5 to 80 parts by weight of an inorganic filler, and 0.1 to 3 parts by weight of an organic peroxide, the rubber base material being composed of a first polybutadiene accounting for 50 to 95 wt % and a second polybutadiene accounting for 5 to 50 wt %, both polybutadiene being synthesized by using a rare earth element-based catalyst, the first polybutadiene containing no less than 60 wt % of cis-1,4 bonds and having a Mooney viscosity (ML1+4 (100° C.)) no lower than 50 and the second polybutadiene containing no less than 60 wt % of cis-1,4 bonds and having a Mooney viscosity (ML1+4 (100° C.)) no higher than 45. The golf ball is characterized by good rebound resilience and good workability with which it is produced.

Abstract: The present invention provides a multi-piece solid golf ball having a core obtained by molding under heat a specific rubber composition and having a cover of at least three layers which is composed of a thermoplastic resin material and encases the core. By optimizing the deflection of the core under a specific load, optimizing the hardness at the center of the core and the hardnesses of the innermost cover layer, outermost cover layer and intermediate cover layer, setting the combined thickness of the cover layers to at least a specific value, and forming the innermost cover layer of a highly neutralized ionomer resin composition, the spin rate of the ball on shots taken with a driver can be significantly reduced, enabling the distance traveled by the ball to be increased. Moreover, the ball has a good feel on shots with a driver.

Abstract: The present invention provides a multi-piece solid golf ball having a core obtained by molding under heat a specific rubber composition and having a cover of at least three layers which encases the core. By optimizing the deflection of the core under a specific load, optimizing the hardness at the center of the core and the hardnesses of the innermost cover layer, outermost cover layer and intermediate cover layer, setting the combined thickness of the cover layers to at least a specific value, and forming the innermost cover layer of a highly neutralized ionomer resin composition, a sufficient reduction in the spin rate of the ball on shots taken with a driver can be achieved, enabling the distance traveled by the ball to be increased.

Abstract: The present invention provides a multi-piece solid golf ball having a core obtained by molding under heat a specific rubber composition and having a cover of at least three layers which encases the core. By optimizing the deflection of the core under a specific load, optimizing the hardness at the center of the core and the hardnesses of the innermost cover layer, outermost cover layer and intermediate cover layer, setting the combined thickness of the cover layers to at least a specific value, and forming the innermost cover layer of a highly neutralized ionomer resin composition, a sufficient reduction in the spin rate of the ball on shots taken with a driver can be achieved, enabling the distance traveled by the ball to be increased.

Abstract: A golf ball including an inner core layer formed from a thermoset rubber composition and having a first surface hardness; a thermoplastic outer core layer having a second surface hardness, an inner surface hardness, and being formed from a copolymer of ethylene and an ?,?-unsaturated carboxylic acid, an organic acid or salt thereof, and sufficient cation source to fully-neutralize the acid groups of the copolymer; an inner cover layer; and an outer cover layer; wherein the first surface hardness is less than the second surface hardness by at least 5 Shore C and less than the inner surface hardness by at least 5 Shore C.

Abstract: A golf ball including an inner core layer formed from a thermoset rubber composition and having a first surface hardness; a thermoplastic outer core layer having a second surface hardness, an inner surface hardness, and being formed from a copolymer of ethylene and an ?,?-unsaturated carboxylic acid, an organic acid or salt thereof, and sufficient cation source to fully-neutralize the acid groups of the copolymer; an inner cover layer; and an outer cover layer; wherein the first surface hardness is substantially the same as the second surface hardness and the inner surface hardness.

Abstract: A golf ball includes an inner core layer formed from a first rubber composition having a first Shore D hardness; an intermediate core layer formed from a second rubber composition; and a thermoplastic outer core layer having a second Shore D hardness. The outer core layer includes a copolymer of ethylene and an ?,?-unsaturated carboxylic acid, an organic acid or salt thereof, and sufficient cation source to fully-neutralize the acid groups of the copolymer. An inner cover layer surrounds the multi-layer core and an outer cover layer is disposed about the inner cover layer. The inner core layer hardness differs from the outer core hardness by at least 10 points.

Abstract: Disclosed herein is novel thermoplastic material and a golf ball utilizing the thermoplastic material. The golf ball (10) preferably comprises a core (12), a cover (16) and optionally a boundary layer (14). At least one of the core (12), cover (16) or boundary layer (14) of the golf ball (10) comprises the thermoplastic material. The thermoplastic material comprises a partially to highly neutralized blend of copolymers additionally comprising a fatty acid or fatty acid salt, and a heavy mass filler in an amount ranging from 10 parts by weight to 50 parts by weight of the material, with the heavy mass filler having a density greater than the copolymer. The golf ball component of the invention has soft feel and resilience that is maintained or improved.

Abstract: A golf ball including an inner core having a first outer surface and a geometric center, the inner core having a hardness of 35 to 55 Shore C; an outer core layer adjacent the inner core having a second outer surface and an inner surface, the outer core layer having a hardness of 55 to 90 Shore C; and a cover layer; wherein the hardness of the first outer surface is substantially the same as or lower than the hardness of the geometric center to define a first negative hardness gradient, and the hardness of the second outer surface is substantially the same as or lower than the hardness of the inner surface to define a second negative hardness gradient.

Abstract: A golf ball includes an inner core having a first outer surface and a geometric center and is formed from a first substantially homogenous formulation throughout such that the inner core has a hardness of 30 Shore C to 45 Shore C. An outer core layer is formed around the inner core and has a second outer surface and an inner surface and is formed from a second substantially homogenous formulation throughout such that the outer core layer has a hardness of 60 Shore C to 95 Shore C. A cover layer is formed around the outer core layer. The hardness of the first outer surface is lower than the hardness of the geometric center to define a negative hardness gradient, and the hardness of the second outer surface is greater than the hardness of the inner surface to define a positive hardness gradient.

Abstract: This invention provides a multi-piece golf ball composed of a core, an intermediate layer enclosing the core, and a cover layer which encloses the intermediate layer and has on an outside surface thereof a plurality of dimples. The cover layer is harder than the intermediate layer. Letting A be the thickness of the intermediate layer, B be the thickness of the cover layer and C be the diameter of the core, 65?C/A?30 and 65?C/B?30. In addition, a specific gravity of the core ranges from 1.0 to 1.2, a specific gravity of the intermediate layer ranges from 0.88 to 1.00, and the ball has an initial velocity, as measured by a method set forth in the Rules of Golf using an initial velocity measuring apparatus of the same type as the USGA drum rotation-type initial velocity instrument, of at least 77.0 m/s.

Abstract: The present invention provides a golf ball material which is a thermoplastic ionomer blend composition of an acid-containing ethylene-based terpolymer having a weight-average molecular weight Mw of at least about 100,000, an acid-containing ethylene-based copolymer and/or terpolymer having a Mw of about 1,500 to about 95,000, and a low-molecular-weight acid-containing compound having a molecular weight of up to about 1,000, at least some portion of which composition is neutralized. The golf ball material is soft and resilient, and has a good durability and improved moldability.

Abstract: The invention provides a multi-piece solid golf ball comprising a core, an envelope layer encasing the core, an intermediate layer encasing the envelope layer, and a cover which encases the intermediate layer and has formed on a surface thereof a plurality of dimples. The core is formed primarily of a rubber material, has a diameter of at least 31 mm, and has a hardness which gradually increases from a center to a surface thereof, the hardness difference in JIS-C hardness units between the core center and the core surface being at least 15 and, letting (I) be the average value for cross-sectional hardnesses at a position 15 mm from the core center and at the core center and letting (II) be the cross-sectional hardness at a position 7.5 mm from the core center, the hardness difference (I)-(II) therebetween in JIS-C units being not more than ±2. The envelope layer and the intermediate layer are each formed primarily of the same or different resin materials.

Abstract: A golf ball comprising a layer made from a liquid rubber composition is disclosed. A castable liquid polybutadiene is the preferred principal rubber component. The molecular weight of the castable liquid polybutadiene is at least about 1,000 and the castable liquid polybutadiene is in a liquid state at room temperature. The castable liquid rubber layer can be a cover layer, a casing layer, an intermediate layer or a core layer.

Abstract: A mixture having good thermal stability, flow and moldability and suitable as a golf ball-forming material is obtained when a base resin comprising a (metal ion-neutralized) olefin-unsaturated carboxylic acid-unsaturated carboxylate ternary random copolymer and optionally a (metal ion-neutralized) olefin-unsaturated carboxylic acid binary random copolymer is blended with specific proportions of a fatty acid and/or fatty acid derivative and a basic inorganic metal compound capable of neutralizing acidic groups left unneutralized in the base resin and fatty acid. Using the same material, high-rebound golf balls can be effectively manufactured.

Abstract: The present invention is directed to a golf ball having at least one layer formed from a moisture resistant, highly neutralized acid polymer composition. Highly neutralized acid polymers of the present invention are produced with a cation source selected from ions and compounds of lithium, ions and compounds of zinc, and combinations thereof. Golf balls of the present invention include one-piece, two-piece, multi-layer, and wound golf balls. The composition may be present in any one or more of a core layer, a cover layer, or an intermediate layer.

Abstract: The present invention provides a golf ball composed of a core, an outermost cover layer and one or more intermediate layer therebetween. At least one intermediate layer includes a mixture composed of a base polymer made of, in a specific ratio, (a) a metal ion neutralization product of an olefin-unsaturated carboxylic acid random copolymer and/or a metal ion neutralization product of an olefin-unsaturated carboxylic acid-unsaturated carboxylic acid ester random copolymer, (b) a thermoplastic elastomer selected from the group consisting of thermoplastic polyester elastomers, thermoplastic block copolymers and thermoplastic polyurethanes, and (c) a thermoplastic block copolymer containing end blocks modified by a functional group having reactivity with an ionomer resin, both end blocks being formed of different comonomers.

Abstract: The invention provides a multi-piece solid golf ball having a rubber-based core encased by, in order, an intermediate layer and a cover. The core contains from 0.05 to 0.5 part by weight of sulfur per 100 parts by weight of the rubber base, has a hardness difference between the surface and center thereof, expressed in JIS-C hardness units, of at least 21 but not more than 30, and has a diameter of from 36 to 40 mm. The intermediate layer has a Shore D hardness of at least 47 but not more than 60, and a thickness of from 0.5 to 2.0 mm. The cover has a Shore D hardness of at least 53 but not more than 60, and a thickness of from 0.6 to 1.5 mm. The intermediate layer and cover satisfy the following condition: 120?(Shore D hardness of intermediate layer×thickness of intermediate layer)+(Shore D hardness of cover×thickness of cover)?150. The golf ball of the invention has, in particular, an excellent feel on impact and an excellent flight performance on shots taken with an iron.

Abstract: A golf ball composition having a copolymer with an acid content modified by a nucleating agent is described. The nucleating agent modifies the flexural modulus of the acid copolymer.

Abstract: The present invention is directed to an improved golf ball displaying the desired spin profile and having a generally rigid, thermoset polybutadiene outer core surrounding a relatively soft, low compression inner core. In general, this golf ball has an inner core and at least one outer core layer surrounding the inner core. The inner core has a hardness less than a hardness of the outer core and a specific gravity less than or equal to the outer core specific gravity. Overall the inner core compression and outer core are formulated to provide a combined overall core compression of greater than about 50, preferably greater than about 70. A cover layer is provided to surround and to cover the outer core layer. A moisture barrier layer is provided between the outer core layer and the cover layer to protect the inner and outer cores from degradation due to exposure to water.