Classifications

• • A—HUMAN NECESSITIES
  • A63—SPORTS; GAMES; AMUSEMENTS
  • A63B—APPARATUS FOR PHYSICAL TRAINING, GYMNASTICS, SWIMMING, CLIMBING, OR FENCING; BALL GAMES; TRAINING EQUIPMENT
  • A63B37/00—Solid balls; Rigid hollow balls; Marbles
  • A63B37/0003—Golf balls
• • A—HUMAN NECESSITIES
  • A63—SPORTS; GAMES; AMUSEMENTS
  • A63B—APPARATUS FOR PHYSICAL TRAINING, GYMNASTICS, SWIMMING, CLIMBING, OR FENCING; BALL GAMES; TRAINING EQUIPMENT
  • A63B37/00—Solid balls; Rigid hollow balls; Marbles
  • A63B37/0003—Golf balls
  • A63B37/005—Cores
  • A63B37/0051—Materials other than polybutadienes; Constructional details
  • A63B37/0052—Liquid cores
• • A—HUMAN NECESSITIES
  • A63—SPORTS; GAMES; AMUSEMENTS
  • A63B—APPARATUS FOR PHYSICAL TRAINING, GYMNASTICS, SWIMMING, CLIMBING, OR FENCING; BALL GAMES; TRAINING EQUIPMENT
  • A63B37/00—Solid balls; Rigid hollow balls; Marbles
  • A63B37/0003—Golf balls
  • A63B37/005—Cores
  • A63B37/0051—Materials other than polybutadienes; Constructional details
  • A63B37/0053—Thread wound
• • A—HUMAN NECESSITIES
  • A63—SPORTS; GAMES; AMUSEMENTS
  • A63B—APPARATUS FOR PHYSICAL TRAINING, GYMNASTICS, SWIMMING, CLIMBING, OR FENCING; BALL GAMES; TRAINING EQUIPMENT
  • A63B37/00—Solid balls; Rigid hollow balls; Marbles
  • A63B37/0003—Golf balls
  • A63B37/005—Cores
  • A63B37/0051—Materials other than polybutadienes; Constructional details
  • A63B37/0054—Substantially rigid, e.g. metal

Definitions

• the invention relates to golf balls and, more particularly, to golf balls having one or more core layer (s), cover layer (s) and/or intermediate layer (s) , wherein at least one of the layers is formed of a poly (trimethylene terephthalate) ("PTT") composition and wherein the PTT composition is either 100 weight percent PTT or a PTT blend with other polymers .
• PTT poly (trimethylene terephthalate)
• the invention also relates to methods for making such golf balls from PTT compositions. Golf balls produced in accordance with the present invention are characterized by improved properties including abrasion resistance, cut resistance and durability.
• Three-piece, wound golf balls with balata covers are preferred by most expert golfers. These balls provide a combination of distance, high spin rate, and control that is not available with other types of golf balls. However, balata is easily damaged in normal play, and, thus, lacks the durability required by the average golfer.
• U.S. Patent No. 5,002,281 to Nakahara et al discloses a three-piece solid golf ball having an ionomer ⁇ " cover and a solid core consisting of a soft inner core surrounded by a hard outer shell, where the difference in the hardness of the two parts of the core is at least 10 on the JIS-C scale.
• U.S. Patent No. 4,781,383 to Kamada et al. discloses a solid, three-piece golf ball, having an
• ⁇ ⁇ ionomer cover and a core with inner and outer layers where the inner layer has a diameter of 24 to 29 mm and a Shore D hardness of 15 to 30, and the outer layer has a diameter of 36 to 41 and a Shore D hardness of 55 to 65.
• European Patent Application 0 633 043 discloses a solid, three-piece golf ball with an ionomer or balata cover,
• the center core has a diameter of at least 29 mm and a specific gravity of less than 1.4.
• the intermediate layer has a thickness of at least 1 mm, a specific gravity of less than 1.2, and a hardness of at least 85 on the JIS-C scale.
• Blending a polymer and an ionomer is one approach
• polyester elastomer urethane elastomer, styrene-butadiene copolymer elastomer and polyester elastomer are said to be preferred when used alone or blended with a matrix resin, that is, another like flexible thermoplastic resin.
• the polyester elastomers are said to include block copoly (ether-esters) , block copoly (lactone-esters) and aliphatic and aromatic dicarboxylic acid copolymerized polyesters.
• the 5 Saito patent does not teach the use of the polyester, poly (trimethylene terephthalate), in a golf ball cover.
• the color of the cover is enhanced by the use of optical brightener in combination with a pigment system.
• optical brightener is desired especially when the cover material is ® not white in appearance.
• the need for a supplemental paint coating can be reduced or eliminated.
• polyolefins and their copolymers discloses blends of optical brighteners with the following golf ball materials: polyolefins and their copolymers; polyurethanes; polyamides, 5 polyamide blends with SURLYN ® , polyethylene, ethylene copolymers and EPDM; vinyl and acrylic resins; thermoplastic rubbers such as urethanes, styrene block copolymers, copoly (ether-amides) and olefinic thermoplastic rubbers; and thermoplastic polyesters such as poly (ethylene terephthalate) (hereinafter “PET”), poly (butylene terephthalate) 0 (hereinafter “PBT”) and PETG.
• PET poly (ethylene terephthalate)
• PBT poly (butylene terephthalate) 0
• the reference contains no teaching, however, to use poly (trimethylene terephthalate) (hereinafter "PTT”) in a pigmented golf ball cover with an optical brightener.
• PTT poly (trimethylene terephthalate)
• poly (trimethylene terephthalate) has been used mainly in carpet fiber and textile applications.
• similarities in tensile strength, flexural modulus, specific gravity, mold shrinkage, melting point, and glass transition temperature suggest that poly (trimethylene terephthalate) can be a good substitute for polyamides and polyamide blends used 0 in golf ball covers, intermediate layers, and cores. Co-pending and co-assigned application no.
• 08/862,831 is directed to compositions and methods for forming golf ball covers, cores and intermediate layers, wherein the composition comprises a blend of a polyamide and poly (trimethylene terephthalate) without optical brightener.
• the disclosure of that reference contains no teaching or suggestion to formulate a composition without polyamide and with optical brightener.
• the present invention provides such a golf ball.
• the present invention is directed to golf balls and in particular, to golf balls having at least one layer comprising poly (trimethylene terephthalate), either alone or in blends with other polymers wherein, when such other polymers are present, i.e., in the blend, they do not include a polyamide polymer.
• poly (trimethylene terephthalate) will generally be used in forming some or all of the cover layer (s) of the golf ball, it may also or alternatively comprise some or all of the core layer (s), and/or intermediate layer (s) .
• the invention includes one-piece golf balls comprising poly (trimethylene terephthalate), either alone or as a blend, with other polymers, as well as two- piece and three-piece golf balls comprising at least one cover layer and a core .
• the golf ball has at least one layer, i.e., a core layer, an intermediate layer and/or a cover layer, comprised of a poly (trimethylene terephthalate) composition,
• poly (trimethylene terephthalate) composition refers to both 100 wt% poly (trimethylene terephthalate) as well as a poly (trimethylene terephthalate) blend comprising from about 1 to about 99 wt% poly (trimethylene terephthalate) and from about 99 to about 1 weight percent of a non- polyamide second polymer component.
• the second polymer component may be a polyurethane, an epoxy resin, a polystyrene, an acrylic, a polyethylene, a polyester, a polycarbonate or an acid copolymer or its ionomer derivative Q or blends thereof.
• the PTT-containing layer has a foamed structure.
• the preferred flexural modulus ranges from 1000 to 150,000 psi.
• the layer preferably has a Shore D hardness of from about 15 to about 80 and a thickness of from about 0.005 to 0.125 inch.
• the layer has a Shore D hardness of 0 from about 15 to about 80 and a thickness of from about 0.005 to 0.125 inch.
• the core preferably has a diameter of from about 1 to 1.63 inch.
• the core comprises a liquid center or a solid 5 polymeric center.
• the core further comprises an elastomer.
• the poly (trimethylene terephthalate) composition comprises an elastomer, such as polybutadiene, a metallic derivative of diacrylate, and from about 1 to about 75 parts by weight poly (trimethylene terephthalate) .
• the PTT is present in an amount of about 1 to 0 about 50 parts by weight. More preferably, the PTT is present in an amount of about 5 to about 40 parts by weight.
• the PTT is present in an amount of about 5 to about 25 parts by weight.
• the invention is directed to a golf ball comprising a cover and a core, wherein the cover comprises a poly (trimethylene terephthalate) composition.
• the invention is directed to three-piece golf balls comprising at least one cover layer, at least one core layer and at least one intermediate layer between the cover and the core, where at least one layer comprises a poly (trimethylene terephthalate) composition.
• the poly (trimethylene terephthalate) is blended with a non-polyamide second polymer component and the second polymer component may be a polyurethane, an epoxy resin, a polystyrene, an acrylic, a polyethylene, a polyester, a polycarbonate or an acid copolymer or its ionomer derivative or blends thereof; and the poly (trimethylene terephthalate) composition may be foamed or unfoamed.
• the blend comprises about 10 to about 75 weight percent of poly (trimethylene terephthalate) and about 90 to about 25 weight percent of the second polymer component. More preferably, the blend comprises about 15 to about 40 weight percent of poly (trimethylene terephthalate) and about 85 to about 60 weight percent of the second polymer component.
• the core of the three-piece golf ball comprise a liquid or solid center.
• the liquid or solid center may be wrapped in elastomeric windings, which may be comprised of a poly (trimethylene terephthalate) composition.
• the liquid center comprises an outer envelope containing a liquid, wherein the envelope is formed of a poly (trimethylene terephthalate) composition.
• the invention provides a method of making a two-piece golf ball.
• the method comprises the steps of forming a golf ball core by conventional means and subsequently forming a cover around the core by either compression molding preformed half-shells of cover stock material comprising poly (trimethylene terephthalate) about the core or by injection molding cover stock material comprising a poly (trimethylene terephthalate) composition, wherein the poly (trimethylene terephthalate) composition may be foamed or unfoamed.
• the poly (trimethylene terephthalate) may be blended with a polyurethane, epoxy resin, polyethylene, polyester, polystyrene, polycarbonate, acrylic or acid copolymer or its ionomer derivative or blends thereof.
• this invention provides a method of making a multi- layer golf ball, which comprises forming a core layer, forming at least one intermediate layer about the core layer, and forming a cover layer over the at least one intermediate layer, wherein at least one of the layers comprises a poly (trimethylene terephthalate) composition and may be foamed or unfoamed.
• the poly (trimethylene terephthalate) of the core layer, intermediate layer and/or cover layer may be blended with one or more conventional ionomeric and/or non-ionomeric thermoplastic polymers.
• the non- ionomer thermoplastic elastomer polymer is selected from the group consisting of a block copolymer of copoly (ester-ester) , a block copolymer of copoly (ester-ether) , a block copolymer of copoly (urethane-ester) , a block copolymer of copoly (urethane-ether) , a block polystyrene thermoplastic elastomer comprising an unsaturated rubber, a block polystyrene thermoplastic elastomer comprising a functionalized substantially saturated rubber, a thermoplastic and elastomer blend comprising polypropylene and ethylene-propylene-diene monomer terpolymer or ethylene- propylene copolymer rubber, where the rubber is dynamically vulcanized, poly (ethylene terephthalate), poly (butylene terephthalate), poly(vinyl alcohol), poly(vinyl acetate), poly (
• foamed poly (trimethylene terephthalate) composition also allows the golf ball designer to adjust the density or mass distribution of the ball to adjust the angular moment of inertia, and, thus, the spin rate and performance of the ball .
• Foamed materials also offer a potential cost savings due to the reduced use of polymeric material .
• a density increasing filler material can be added to the cover or the intermediate layer to distribute the mass of the ball towards the outer surface and increase the angular moment of inertia.
• the density increasing filler material can be added to the core to decrease the angular moment of inertia.
• a density increasing filler material can be added to either the cover or the core .
• novel golf ball of the invention offers improved mechanical properties in comparison to golf balls disclosed in the prior art, for instance, improved abrasion 0 resistance, cut-resistance and durability. Further these balls also provide enhanced distance (i.e., resilience) without adversely affecting, and in many instances while improving, their "playability" characteristics, i.e., their impact resistance, spin, "click” and “feel", compression, 5 etC -
• the invention is directed to methods and compositions for use in the manufacture of golf balls, Q particularly, golf ball cores, covers and/or intermediate layers.
• the golf balls of this invention have demonstrated improved durability, initial velocity and shear resistance.
• pph refers to parts per hundred parts by weight of a base material.
• fillers includes any compound or composition such as could be well known to one of ordinary skill in the art that may be used to vary the density and/or hardness properties of the golf ball.
• the term "layer” includes any generally spherical portion of a golf ball or golf ball core, center, or intermediate portion, including one-piece cores and one-piece balls.
• An "intermediate layer” is defined as a portion of the golf ball that occupies a portion of the volume between the cover and the core.
• any of the core, cover, and intermediate layer (s) of the golf balls of the invention can be formed of one layer or a plurality of "layers", as that term is defined herein.
• the polymer blends i.e., two or more polymers mixed with each other, of this invention can be prepared with blend components of varying molecular architecture.
• parameters which may be varied include molecular weight, molecular weight distribution, tacticity and optionally, branching, degrees and arrangements of blockiness, block molecular weight and block molecular weight distribution, as is well known to those knowledgeable in the art of blending polymers .
• a "copolymer” is defined as a polymer comprising at least two different monomeric units.
• Copolymer as are polymer chains containing more than three different monomeric units .
• Copolymers may be formed in many ways known to those of ordinary skill in the art, for example, by polymerizing two or more different monomers, by graft copolymerization or block copolymerization, wherein an existing polymer chain is further reacted with a different monomer, and by a post-polymerization reaction, e.g., partial hydrolysis of the ester side-groups of a polymer.
• non-polyamide polymer is used to refer to a polymer without a plurality of amide units or moieties in the chain.
• the core assembly may be a liquid center, a solid center, or a liquid or solid center wrapped in elastomeric windings.
• liquid center refers to an outer envelope surrounding or containing a liquid.
• the invention contemplates a golf ball having at least one layer comprising poly (trimethylene terephthalate).
• the poly (trimethylene terephthalate may be blended with polyurethanes, epoxy resins, polystyrenes, acrylics, polyethylenes, polyesters, polycarbonates or acid copolymers or their ionomer derivatives or blends thereof.
• Poly (trimethylene terephthalate) is an aromatic polyester which is a copolymer of trimethylene glycol and terephthalic acid.
• the synthesis of poly (trimethylene terephthalate) was first disclosed in U.S. Patent No.
• the poly (trimethylene terephthalate) useful in the invention can be synthesized by a variety of methods.
• a synthetic route known to be used by Shell Chemical begins with the production of trimethylene glycol, a starting material for the synthesis of pTT.
• Trimethylene glycol is produced from the hydroformation of ethylene oxide, as shown below:
• PTT fibers for use in carpet fiber applications have unexpectedly superior properties when compared with poly (ethylene terephthalate) and poly (butylene terephthalate) . Without being bound by theory, it is believed that these unexpected properties are examples of the "odd carbon" effect, whereby polymers containing the three-carbon PTT exhibit unexpected properties in comparison to polymers with two carbon PET and/or the four carbon PBT.
• polyamides and polyamide blends used in golf ball covers, intermediate layers, and cores.
• Poly (trimethylene terephthalate) is also an excellent replacement for nylon 6 and nylon 6/6, which are also used in forming golf balls.
• co-pending and co-assigned application no. 08/862,831 is directed to compositions and methods for forming golf ball covers, cores and intermediate layers, wherein the composition comprises a blend of a polyamide and poly (trimethylene terephthalate) and is substantially free of optical brightener.
• this disclosure contains no teaching or suggestion to formulate a polyamide blend with PTT and optical brightener.
• optical brightener may be used with PTT. However, it is not be necessary that an optical brightener be used with PTT since PTT is already white in appearance. As noted by Traub et al . in Die Angewandte Makromolekulare Chemie 230
• poly (trimethylene terephthalate) comprises from about 1 to about 100 percent by weight of the golf ball cover composition and/or the intermediate layer composition. Unless otherwise stated herein, all percentages are given in percent by weight of the total composition.
• the golf ball cover and/or intermediate layer comprises PTT and a second polymer component, wherein the PTT comprises from about 10 to about 90%, more preferably from. about 10 to about 75% and most preferably from about 15 to about 40%; wherein the second polymer component comprises about 90 to 10%, more preferably from about 90 to about 25% and most preferably from about 85 to about 60%; and wherein the second polymer component is comprised of one or more polymers such as, but not limited to conventionally produced
• the polymer compositions may be foamed during molding by any conventional foaming or blowing agent .
• foamed poly (trimethylene terephthalate) compositions may be thermoformed, and, thus can be compression molded. Therefore, either injection molding or compression molding may be used to form a layer of foamed poly (trimethylene terephthalate) polymer in the cover layer, core layer, or intermediate layer of a golf ball according to the invention.
• Poly (trimethylene terephthalate) polymers and poly (trimethylene terephthalate) polymer blends are resilient, easily processed materials that are less expensive than ionomers, and allow highly durable golf balls to be produced with virtually any combination of feel and spin rate .
• Conventional ionomers useful in this invention may include SURLYN ® , ESCOR ® , IOTEK ® , and IMAC ® copolymers.
• Such ionomers are obtained by providing thermolabile ionic crosslinking to polymers of monoolefin with at least one member selected from the group consisting of unsaturated mono- or di-carboxylic acids having 3 to 12 carbon atoms and esters thereof (the polymer contains 1 to 50% by weight of the unsaturated mono- or di-carboxylic acid and/or ester thereof) .
• such acid-containing ethylene copolymer ionomer component includes E/X/Y copolymers where E is ethylene, X is a softening comonomer such as acrylate or methacrylate present in 0-50 (preferably 0-25, most preferably 0-20) , weight percent of the polymer, and Y is acrylic or methacrylic acid present in 5-35 (preferably 10- 35, more preferably at least about 16-35, most preferably at least about 16-20) weight percent of the polymer, wherein the acid moiety is neutralized 1-90% (preferably at least 40%, most preferably at least about 60%) to form an ionomer by a cation such as lithium, sodium, potassium, magnesium, calcium, barium, lead, tin, zinc or aluminum, or a combination of such cations.
• a cation such as lithium, sodium, potassium, magnesium, calcium, barium, lead, tin, zinc or aluminum, or a combination of such cations.
• ethylene copolymers include ethylene/acrylic acid, ethylene/methacrylic acid, ethylene/acrylic acid/n-butyl acrylate, ethylene/methacrylic acid/n-butyl acrylate, ethylene/methacrylic acid/iso-butyl acrylate, ethylene/acrylic acid/iso-butyl acrylate, ethylene/methacrylic acid/n-butyl methacrylate, ethylene/acrylic acid/methyl methacrylate, ethylene/acrylic acid/methyl acrylate, ethylene/methacrylic acid/methyl acrylate, ethylene/methacrylic acid/methyl methacrylate, and ethylene/acrylic acid/n-butyl methacrylate.
• Preferred acid- containing ethylene copolymers include ethylene/methacrylic acid, ethylene/acrylic acid, ethylene/methacrylic acid/n- butyl acrylate, ethylene/acrylic acid/n-butyl acrylate, ethylene/methacrylic acid/methyl acrylate and ethylene/acrylic acid/methyl acrylate copolymers.
• the most preferred acid-containing ethylene copolymers are ethylene/methacrylic acid, ethylene/acrylic acid, ethylene/ (meth) acrylic acid/n-butyl acrylate, ethylene/ (meth) acrylic acid/ethyl acrylate, and ethylene/ (meth) acrylic acid/methyl acrylate copolymers.
• cover and/or intermediate layers include ionomers, polyurethanes, epoxy resins, polystyrenes, acrylics, polyethylenes, polycarbonates and polyesters.
• the cover and/or intermediate layer may be formed from a blend of PTT and conventionally produced thermoplastic or thermoset urethanes/polyurethanes, urethane ionomers and urethane epoxies and blends thereof .
• thermoplastic polyurethanes are block copolymers of copolyurethanes which typically contain blocks of a polyurethane oligomer (material with the higher softening point) alternating with lower softening point
• - 14 blocks of either a polyether oligomer, for a block copoly (ether-urethane) , a polyester oligomer for a block copoly (ester-urethane) or a polybutadiene or hydrogenated polybutadiene oligomer for a block copoly (butadiene- urethane) .
• the polyether oligomer is typically a polyether macroglycol, such as polytetramethylene ether glycol.
• the polybutadiene oligomer is a dihydroxy terminated polybutadiene oligomer, which may optionally be partially or fully hydrogenated.
• the polyurethane block typically consists of 4 , 4 ' -diphenylmethane diisocyanate, toluene diisocyanate (any combination of the 2,4- and 2,6- isomers) or para-phenylene diisocyanate, all chain extended with an aliphatic diol, typically 1 , 4-butanediol .
• suitable commercially available thermoplastic polyurethanes include the ESTANE ® series from the B.F.
• PTT can also be blended with an epoxy resin.
• An epoxy resin A generic representation of the structure of suitable epoxy resins is described below:
• Suitable commercially available epoxy resins include but are not limited to "Epon” resins available from Shell and “Novalac” resins from Dow.
• Suitable polyethylenes for blending with PTT to form the cover and/or intermediate layer include homo and copolymers of ethylene containing functional groups such as maleic anhydride, carboxylic acid and hydroxyl groups.
• these functional groups are introduced either by chemical grafting as in the case of grafting maleic anhydride such as that sold commercially under the tradename "FUSABOND” by DuPont (Canada) , or by copolymerizing the ethylene monomer with an unsaturated carboxylic acid comonomer such as a methacrylic acid sold commercially under the tradename "NUCREL” by DuPont.
• R substituted and unsubstituted aliphatic, cyclic or aromatic
• R 1 aliphatic or aromatic (e.g. bisphenol - A or bisphenol - S); and n > 50
• Catalysts such as manganese acetate, antimony oxide and titanium alkoxides are commonly used producing polyester polymers.
• suitable commercially available polyesters include materials sold under the tradenames "EASTPAK” PET polyester and “EASTAR” PETG from Eastman Chemicals, "DACRON” and “TERGLENE” from DuPont.
• - 16 - ball cover and/or intermediate layer compositions include: poly (ethylethylene) , poly (heptylethylene) , poly (hexyldecylethylene) , poly (isopentylethylene) , poly(l,l- dimethyltrimethylene) , poly (1, 1, 2-trimethyltrimethylene) , aliphatic polyketones (such as ethylene-carbon monoxide- propylene sold commercially under the tradename "CARILON” by Shell), poly(butyl acrylate), poly (4-cyanobutyl acrylate), poly (2-ethylbutyl acrylate), poly(heptyl acrylate), poly(2- methylbutyl acrylate), poly (3-methylbutyl acrylate), poly (octadecyl methacrylate), poly (butoxyethylene) , poly (methoxyethylene) , poly (pentyloxyethylene) , poly(l,l- dichloroethylene) , poly (cyclopen
• non-ionomeric thermoplastic polymers may include: block copolymer of poly (ether-ester) copolymers, such as HYTREL ® available from DuPont, partially or fully hydrogenated styrene-butadiene-styrene block copolymers, such as the KRATON D ® grades available from Shell Chemical, styrene- (ethylene-propylene) -styrene or styrene- (ethylene- butylene) -styrene block copolymers, such as the KRATON G ® series from Shell Chemical, Septon HG-252 from Kurary, either of the KRATON ® -type copolymers with maleic anhydride or sulfonic graft or hydroxyl functionality, such as the KRATON FD ® or KRATON FG
• - 17 - catalysts such as the AFFINITY ® or ENGAGE ® series available from Dow, ethylene-alpha olefin copolymers and terpolymers made from metallocene catalysts, such as the EXACT ® series available from Exxon, block copolymer of poly (urethane-ester) or block copolymer of poly (urethane-ether) or block copolymer of poly (urethane-caprolactone) , polyethylene glycol, such as CARBOWAX ® available from Union Carbide, polycaprolactone, polycaprolactam, polyesters, such as EKTAR ® available from Eastman, ethylene-propylene- (diene monomer) terpolymers and their sulfonated or carboxylated derivatives, and SANTOPRENE ® from Monsanto.
• the polymer blends of this invention can be prepared with or without the addition of a compatibilizer and with varying molecular architecture of blend components, such as varying molecular weight, tacticity, degrees of blockiness, etc., as is well known to those knowledgeable in the art of blending polymers .
• Blending of the polymers is accomplished in a conventional manner using conventional equipment. Good results have been obtained by mixing the polymers or resins in a solid, pelletized form and then placing the mix into a hopper which is used to feed the heated barrel of an injection molding machine. Further mixing is accomplished by a screw in the heated barrel.
• the injection molding machine is used either to make preformed half-shells for compression molding about a core or for molding flowable cover stock about a core using a retractable-pin mold. Such machines are conventional .
• cover compositions of the invention include white pigments, optical brighteners, processing aids and U.V. stabilizers such as TINUVINTM 213 and TINUVINTM 328. Also, light stabilizers such as, for example, TINUVINTM 770 and TINUVINTM 765, may also be used. TINUVINTM products are available from Ciba-Geigy. Dyes, as well as fluorescent pigments may also be used in the golf ball covers produced with polymers formed according to
• Such additional ingredients may be used in any amounts that will achieve their desired purpose. However conventional amounts range of from about 0.05% to about 1.5%, or more preferably, from about 0.5% to about 1.0%.
• An optional filler component may be chosen to impart additional density to blends of the previously described components.
• the selection of such filler (s) is dependent upon the type of golf ball desired (i.e., one- piece, two-piece multilayer or wound) , as will be more fully detailed below.
• the filler will be inorganic, having a density greater than about 2 g/cc, preferably greater than 4 g/cc, and will be present in amounts between 5 and 65 weight percent based on the total weight of the polymer components.
• useful fillers include metals, such as tungsten and titanium; metal alloys, such as brass and bronze; metal oxides, such as zinc oxide and calcium oxide; metal salts, such as barium sulfate, lead silicate and tungsten carbide; and other well known corresponding salts and oxides thereof.
• PTT may be added to conventional core compositions to form cores for two-piece balls or centers of wound balls.
• Conventional core compositions comprise polybutadiene as the elastomer and, in parts by weight based on 100 parts polybutadiene (pph) , 20-50 pph of a metal salt acrylate derivative such as zinc diacrylate, zinc dimethacrylate, or zinc monomethacrylate, preferably zinc diacrylate and up to about 75 pph of PTT.
• pph polybutadiene
• a metal salt acrylate derivative such as zinc diacrylate, zinc dimethacrylate, or zinc monomethacrylate, preferably zinc diacrylate and up to about 75 pph of PTT.
• the PTT is present in an amount of about 1 to about 50 pph. More preferably, the PTT is present in an amount of about 5 to about 40 pph. Most preferably, the PTT is present in an amount of about 5 to
• the core compositions of this invention may be foamed or unfoamed.
• compositions of the invention may also include fillers, added to the elastomeric composition to adjust the density and/or specific gravity of the core.
• Fillers useful in the golf ball core according to the invention include, for example, zinc oxide, calcium oxide, barium sulfate, and regrind (which is recycled core molding matrix ground to 20 mesh particle size) .
• the amount and type of filler utilized is governed by the amount and weight of other ingredients in the composition, since a maximum golf ball weight of 1.620 ounces (45.92 gm) has been established by the USGA.
• Appropriate fillers including reactive fillers, known by those skilled in the art, generally have a specific gravity in the range of from about 2.0 to 5.6.
• Antioxidants may also be included in the elastomer cores produced according to the invention. Antioxidants are compounds which prevent the breakdown of the elastomer. Antioxidants useful in the invention include, but are not limited to, quinoline type antioxidants, amine type antioxidants, and phenolic type antioxidants.
• ingredients such as accelerators, e . g. tetra methylthiuram, processing aids, processing oils, plasticizers, dyes and pigments, as well as other additives well known to the skilled artisan may also be used in the invention in amounts sufficient to achieve the purpose for which they are typically used.
• the core compositions of the invention may be produced by forming a mixture comprising, for example, polybutadiene, zinc diacrylate, and PTT.
• a set of predetermined conditions i.e., time and temperature of mixing
• the free radical initiator is added in an amount dependent upon the amounts and relative ratios of the starting components, all of which would be well understood by one of ordinary skill in the art.
• the resultant is a set of predetermined conditions, i.e., time and temperature of mixing.
• Peroxide (s) free radical initiator (s) are blended into the mixture for crosslinking purposes in the molding process.
• the golf ball core composition is milled and hand prepped or extruded into pieces ("preps") suitable for molding.
• the milled preps are then compression molded into cores at an elevated temperature. These cores can then be used to make finished golf balls by surrounding the cores with an intermediate layer and/or cover materials .
• Layers formed of a poly (trimethylene terephthalate) composition may be produced in golf balls in accordance with the invention by injection molding or compression molding a layer of a poly (trimethylene terephthalate) composition about a previously formed center or core, cover, or intermediate layer. Cores comprising a poly (trimethylene terephthalate) composition may also be formed directly by injection molding or compression molding. When the layer or core is injection molded, a physical or chemical blowing or foaming agent may be included to produce a foamed layer.
• Blowing or foaming agents useful in forming foamed poly (trimethylene terephthalate) compositions include, but are not limited to organic blowing agents, such as azobisformamide; azobisisobutyronitrile; diazoaminobenzene; N,N-dimethyl-N,N-dinitroso terephthalamide; N, N-dinitrosopentamethylene-tetramine ; benzenesulfonyl-hydrazide; benzene-1, 3 -disulfonyl hydrazide; diphenylsulfon-3 -3 , disulfonyl hydrazide; 4,4'-oxybis benzene sulfonyl hydrazide; p-toluene sulfonyl semicarbizide; barium azodicarboxylate; butylamine nitrile; nitroureas; trihydrazino triazine; phenyl-methyl-
• microspheres with the poly (trimethylene terephthalate) composition either during or before the molding process.
• Polymeric, ceramic, metal, and glass microspheres are useful in the invention, and may be solid or hollow and filled or unfilled.
• Microspheres up to about 1000 micrometers in diameter are useful in the poly (trimethylene terephthalate) compositions of the invention.
• the invention is further directed to a method of making a golf ball.
• the method comprises, in one embodiment, the steps of forming a golf ball core by conventional means and subsequently forming a cover around the core by either compression molding preformed half-shells of cover stock material comprising a poly (trimethylene terephthalate) composition about the core or by injection molding cover stock material comprising the poly (trimethylene terephthalate) composition about the core.
• the poly (trimethylene terephthalate) is blended with a non- polyamide second polymer component and the non-polyamide second component is a polyurethane, epoxy resin, polystyrene, acrylic, polyethylene, polyester, polycarbonate or acid copolymer or its ionomer derivative or blends thereof.
• the polymer compositions in this invention may be foamed or unfoamed.
• the invention further provides a method of making a golf ball, which comprises forming a core layer, forming at least one intermediate layer about the core layer, and forming a cover layer over the at least one intermediate layer, where at least one of the layers comprises a poly (trimethylene terephthalate) composition, wherein the PTT is either alone or blended with other polymers.
• the poly (trimethylene terephthalate) of the core, intermediate and/or cover layer may be blended with one or more conventional ionomeric and/or non-ionomeric thermoplastic polymers.
• the polymer compositions in this invention may be foamed or unfoamed.
• the non- ionomer thermoplastic elastomer polymer is selected from the group consisting of a block copolymer of
• esters-ester a block copolymer of copoly (ester- ether) , a block copolymer of copoly (urethane-ester) , a block copolymer of copoly (urethane-ether) , a block polystyrene thermoplastic elastomer comprising an unsaturated rubber, a block polystyrene thermoplastic elastomer comprising a functionalized substantially saturated rubber, a thermoplastic and elastomer blend comprising polypropylene and ethylene-propylene-diene monomer terpolymer or ethylene- propylene copolymer rubber where the rubber is dynamically vulcanized, poly (ethylene terephthalate), poly (butylene terephthalate), poly(vinyl alcohol), poly(vinyl acetate), poly (silane) , poly (vinylidene fluoride), acrylonitrile- butadiene-styrene thermoplastic elastomer comprising an
• One-piece golf balls comprising PTT, either alone or as a blend with other polymers, two-piece golf balls comprising a cover surrounding a core and wound golf balls, in which a liquid, semi-solid, or solid core is surrounded by an elastic synthetic material are all within the scope of the invention.
• Any type of golf ball core can be used in the golf balls of the invention.
• preferred cores include some amount of cis-polybutadiene .
• the covers are formed around the solid or wound cores by either compression molding preformed half- shells of the cover stock material or by injection molding the cover stock about the core.
• Half-shells are made by injection molding a cover stock into a conventional half- shell mold in a conventional manner. The preferred method is compression molding of preformed half-shells.
• the half-shells of the stock material are formed by injection molding the cover stock material at 300°F-520°F into a conventional half-shell mold for a short time.
• the preformed half-shells are then placed about a core and the assembly is introduced into a compression molding machine.
• the compression molding machine is a hydraulic press having an upper and lower mold plate.
• golf balls can be covered solely with the use of an injection molding technique utilizing an injection molding machine in which the core assembly is placed in a mold cavity. The core assembly is held in place through the use of several retractable pins in a known manner.
• injection molding machines are well known in the art.
• the molten cover material is injected into the cavity surrounding the core. As the cover material cools and hardens, the pins retract and the molded ball is ejected from the mold. The balls then undergo conventional finishing operations such as buffing, painting and stamping.
• the invention can be used in forming golf balls of any desired size. "The Rules of Golf" by the USGA dictate that the size of a competition golf ball must be more than 1.680 inches in diameter, golf balls of any size can be used for leisure golf play.
• the preferred diameter of the golf balls is from about 1.680 inches to about 1.800 inches. The more preferred diameter is from about 1.680 inches to about 1.760 inches.
• a diameter of from about 1.680 inches to about 1.740 inches is most preferred, however diameters anywhere in the range of from 1.70 to about 1.95 inches can be used. Oversize golf balls with diameters above about 1.760 inches to as big as 2.75 inches are also within the scope of the invention.

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• 1998
  • 1998-04-20 US US09/063,116 patent/US6232400B1/en not_active Expired - Fee Related
• 1999
  • 1999-04-19 WO PCT/US1999/008555 patent/WO1999054001A1/en not_active Ceased
  • 1999-04-19 GB GB0025649A patent/GB2352980A/en not_active Withdrawn
  • 1999-04-19 JP JP2000544399A patent/JP2002512097A/ja active Pending
  • 1999-04-19 AU AU36529/99A patent/AU3652999A/en not_active Abandoned
• 2001
  • 2001-05-09 US US09/851,894 patent/US6534596B2/en not_active Expired - Fee Related

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