JP2004290668A - Golf ball - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a golf ball having a coating film with superior adhesion property, durability and discoloring resistance. <P>SOLUTION: This golf ball is provided with the coating film on the surface of the golf ball. The coating film contains 0.05-5 pts.mass of phosphorus-based stabilizer relative to the 100 pts.mass of resin component. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a golf ball, and more particularly, to a painted golf ball having a golf ball surface coated with a coating film.

The surface of the golf ball is provided with a coating film for imparting gloss and protecting the mark and the golf ball body. The coating film is required to have such properties as adhesion and durability that do not peel off even upon impact upon impact, and weather resistance that does not discolor or deteriorate even under sunlight or rain. For example, Patent Document 1 proposes a method of manufacturing a golf ball in which an adhesion reinforcing layer containing a silyl compound is provided between a coating film and the surface of a golf ball body to improve the adhesion of the coating film. As a golf ball having a weather-resistant coating film, Patent Document 2 discloses a golf ball having a clear coating film containing a hindered phenolic antioxidant, and Patent Document 3 discloses a fluorescent whitening agent. And a golf ball having a clear coating containing an ultraviolet absorber.
JP-A-12-342718, page 2 JP-A-7-51403, page 2 JP 2001-17576A, page 2

  Since golf balls are extremely severely deformed at impact and used under severe conditions such as friction with the ground, strong adhesion is required between the coating film and the golf ball body. ing. When the coating film peels off from the golf ball, not only does the appearance of the golf ball deteriorate, but also the golf ball body is exposed to sunlight such as ultraviolet rays, which causes the performance of the golf ball to deteriorate with time. In particular, golf balls at a driving range are used after being repeatedly brushed and washed in addition to being repeatedly hit, and the coating film must have durability in addition to adhesion to the golf ball. . From these viewpoints, it is extremely important to improve the adhesion and durability of the coating film. Further, for example, even in the case of the coating film disclosed in Patent Document 2, the coating film may change color with time. It is considered that this is because the hindered phenol-based antioxidant used as an antioxidant changes into a compound that develops a color such as yellow or red.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a golf ball having a coating film having excellent adhesion, durability, and resistance to discoloration.

  The golf ball of the present invention capable of solving the above problems is a golf ball having a coating film on the surface of a golf ball, wherein the coating film is 0.05 to 100 parts by mass of a resin component. It is characterized by containing 5 parts by mass of a phosphorus-based stabilizer. According to the present invention, by adding a phosphorus-based stabilizer to a coating film, in addition to improving the discoloration resistance of the coating film, adhesion and durability to a golf ball can be imparted to the coating film. it can. It is preferable to use a phosphorous compound, a hypophosphorous compound, or a derivative thereof as the phosphorus stabilizer. Further, as the resin component of the coating film, for example, urethane resin can be mentioned. When the golf ball of the present invention is a golf ball having a cover, it is preferable to use an ionomer resin or a urethane resin as the cover material. This is because a coating film containing a phosphorus-based stabilizer shows good adhesion to an ionomer resin cover or a urethane resin cover. The coating film preferably has a single-layer structure.

  ADVANTAGE OF THE INVENTION According to this invention, there is no discoloration of a coating film with time, and the coated golf ball excellent in adhesiveness and durability is obtained. In particular, a coated golf ball having excellent adhesion and durability to the surface of a golf ball composed of rubber, ionomer resin, urethane resin, or the like can be obtained.

  The golf ball of the present invention is a golf ball in which a coating film is provided on a golf ball surface, wherein the coating film contains a resin component and a phosphorus-based stabilizer, and is based on 100 parts by mass of the resin component. , 0.05 to 5 parts by mass of a phosphorus-based stabilizer.

  First, the phosphorus-based stabilizer will be described. The phosphorus-based stabilizer used in the present invention not only prevents discoloration of the coating over time, but also imparts adhesion and durability to the coating. From such a viewpoint, the coating film has a resin component of 100 parts by mass, 0.05 parts by mass or more, more preferably 0.1 parts by mass or more, 5 parts by mass or less, more preferably 4 parts by mass or less. Contains a phosphorus stabilizer. When the content of the phosphorus-based stabilizer is less than 0.05 parts by mass, the effect of improving the phosphorus-based stabilizer such as adhesion and durability becomes insufficient, and the content of the phosphorus-based stabilizer exceeds 5 parts by mass. This is because the discoloration resistance is improved, but the adhesion and durability are rather lowered.

  By adding a phosphorus-based stabilizer to the coating film, the reason why the coating film can be provided with adhesion and durability is not clear, but in the present invention, as the phosphorus-based stabilizer, a stabilizer derived from phosphorus oxo acid is used. For example, a hypophosphorous compound (phosphinic acid compound), a phosphorous compound (phosphonic acid compound), or a derivative thereof can be preferably used.

  As the hypophosphorous compound, it is preferable to use hypophosphite and its derivative (phosphinic acid ester and its derivative). Examples of the diphosphite and derivatives thereof include tetrakis (2,4-di-t-butylphenyl) [1,1′-biphenyl] -4,4′-diylbisphosphonite and tetrakis (2 , 4-di-t-butyl-5-methylphenyl) [1,1′-biphenyl] -4,4′-diylbisphosphonite.

  Examples of the phosphite compound include a phosphite having at least one functional group selected from the group consisting of an alkyl group, a phenyl group and an alkylphenyl group, and derivatives thereof (phosphonates and derivatives thereof). Examples thereof include tris (alkylphenyl) phosphite, tris (alkyl) phosphite, and pentaerythritol phosphite derivative.

  Examples of the phosphite and derivatives thereof include tris (nonylphenyl) phosphite and tris (alkylphenyl) phosphite such as tris (2,4-di-t-butylphenyl) phosphite; di (tridecyl) Pentaerythritol diphosphite, di (nonylphenyl) pentaerythritol diphosphite, diisodecylpentaerythritol diphosphite, distearylpentaerythritol diphosphite, di (2,4-di-t-butylphenyl) pentaerythritol diphosphite Di (2,6-di-t-butyl-4-methylphenyl) pentaerythritol diphosphite, hydrogenated bisphenol A pentaerythritol phosphite polymer, tetraphenyltetra (tridecyl) pentaerythritol Pentaerythritol phosphite derivatives such as rutetraphosphite; other, phenyldiisodecyl phosphite; cyclic neopentanetetrayl (octadecyl phosphite); 2,2′-methylenebis (4,6-di-t-butylphenyl) Octyl phosphite; hydrogenated bisphenol A phosphite polymer; tetra (tridecyl) -4,4′-isopropylidene diphenyl diphosphite; tetraphenyl dipropylene glycol diphosphite.

  Among them, tetrakis (2,4-di-t-butylphenyl) [1,1′-biphenyl] -4,4′-diylbisphosphonite (the following formula 1), tetrakis (2,4-di-phenyl) t-butyl-5-methylphenyl) [1,1′-biphenyl] -4,4′-diylbisphosphonite (formula 2 below), tris (2,4-di-t-butylphenyl) phosphite ( The following formula 3), distearylpentaerythritol diphosphite (following formula 4), di (2,4-di-t-butylphenyl) pentaerythritol diphosphite (following formula 5), di (2,6-di- t-butyl-4-methylphenyl) pentaerythritol diphosphite (following formula 6), 2,2′-methylenebis (4,6-di-t-butylphenyl) octylhofffight (following formula 7) and the like Stabilizer It is preferable to use as. This is because a coating film having excellent adhesion and durability as well as discoloration resistance can be obtained.

  Further, the resin component of the coating film of the golf ball of the present invention is not particularly limited as long as it is a resin used as a coating component of the golf ball, for example, acrylic resin, epoxy resin, urethane resin, polyester resin, Cellulose-based resins and the like can be used, and it is preferable to use two-part curable urethane resins described later. If a two-component curable urethane resin is used as a resin component, a coating film having excellent abrasion resistance and durability can be obtained.

  The two-component curable urethane resin is a urethane resin obtained by reacting and curing a main agent and a curing agent. For example, a main agent containing an isocyanate group-terminated urethane prepolymer is cured with a curing agent having active hydrogen. And those obtained by curing a main component containing a polyol component with a polyisocyanate or a derivative thereof.

  In the present invention, it is a particularly preferred embodiment that a two-component curable urethane resin obtained by curing a main component containing a polyol component with a curing agent such as polyisocyanate or a derivative thereof is used as the resin component of the coating film.

  As the main agent containing the polyol component, for example, it is preferable to use a specific urethane polyol as shown below. The urethane polyol is not particularly limited as long as it has a urethane bond and at least two or more hydroxyl groups (preferably at the terminal). For example, the hydroxyl group of the polyol component is in a molar ratio to the isocyanate group of the polyisocyanate. It is obtained by reacting a polyol and a polyisocyanate in such a ratio as to be excessive.

The polyisocyanate constituting the urethane polyol is not particularly limited as long as it has two or more isocyanate groups. For example, 2,4-toluene diisocyanate, 2,6-toluene diisocyanate, 2,4-toluene diisocyanate and 2 A mixture of 2,6-toluene diisocyanate (TDI), 4,4′-diphenylmethane diisocyanate (MDI), 1,5-naphthylene diisocyanate (NDI), 3,3′-bitrylene-4,4′-diisocyanate (TODI), Aromatic polyisocyanates such as xylylene diisocyanate (XDI), tetramethyl xylylene diisocyanate (TMXDI) and paraphenylene diisocyanate (PPDI); 4,4′-dicyclohexylmethane diisocyanate (H ₁₂ MDI), hydrogenated One or a mixture of two or more of alicyclic polyisocyanate or aliphatic polyisocyanate such as xylylene diisocyanate (H ₆ XDI), hexamethylene diisocyanate (HDI) and isophorone diisocyanate (IPDI) can be used. Among these, from the viewpoint of weather resistance, non-yellowing polyisocyanate (TMXDI, XDI, HDI, H 6 XDI, IPDI, H 12 MDI , etc.) are preferably used. The above-mentioned polyisocyanate can also be used as a curing agent for curing urethane polyol.

  The polyol used for the production of the urethane polyol is not particularly limited as long as it has a plurality of hydroxyl groups. For example, a low molecular weight polyol or a high molecular weight polyol can be used. Examples of low molecular weight polyols include diols such as ethylene glycol, diethylene glycol, triethylene glycol, 1,3-butanediol, 1,4-butanediol, neopentyl glycol, and 1,6-hexanediol; glycerin, trimethylol And triols such as propane and hexanetriol. Examples of high molecular weight polyols include polyether polyols such as polyoxyethylene glycol (PEG), polyoxypropylene glycol (PPG), and polyoxytetramethylene glycol (PTMG); polyethylene adipate (PEA), polybutylene adipate (PBA) ), Condensation-based polyester polyols such as polyhexamethylene adipate (PHMA); lactone-based polyester polyols such as poly-ε-caprolactone (PCL); polycarbonate polyols such as polyhexamethylene carbonate; and acrylic polyols. Among the above polyols, those having a weight average molecular weight of 50 to 2,000, particularly those having a weight average molecular weight of about 100 to 1,000 are preferably used. In addition, you may use these polyols individually or in mixture of 2 or more types.

  In the urethane polyol, the ratio of urethane bonds in the urethane polyol is preferably 0.1 to 5 mmol per 1 g of the urethane polyol. The urethane bond ratio is related to the rigidity of the formed coating film. If the ratio is less than 0.1 mmol / g, the urethane bond concentration in the formed coating film is low, and the scratch resistance tends to be insufficient. is there. On the other hand, if it exceeds 5 mmol / g, the coating film tends to be too hard.

  The urethane polyol has a weight average molecular weight of 4,000 or more, preferably 4,500 or more, and less than 10,000, and preferably 9,000 or less. If it is less than 4,000, it takes a long time to dry, and the workability and productivity tend to decrease. On the other hand, in the case of urethane polyol having a high molecular weight of 10,000 or more, the hydroxyl value of the urethane polyol becomes relatively small, and the reaction amount after coating tends to be small, so that the adhesion to the base tends to be reduced. Further, when the weight average molecular weight is 9,000 or less, a dense coating film with little decrease in adhesion can be formed even in a state where the film is wet with water.

  Further, the hydroxyl value (mgKOH / g) of the urethane polyol is preferably 15 or more, more preferably 73 or more, and 130 or less, more preferably 120 or less. If the amount is less than 15 (mgKOH / g), the reaction amount with the curing agent is insufficient, so that the adhesion to the ball body tends to decrease. On the other hand, if it exceeds 130 (mgKOH / g), it takes a long time to react with the curing agent, so that the drying time becomes longer and the productivity decreases.

  The above-mentioned urethane polyol is obtained, for example, by reacting the above-mentioned polyol with polyisocyanate. At the time of the reaction, a solvent or a known catalyst (such as dibutyltin dilaurate) for the urethane-forming reaction can be used. The ratio of urethane bonds can be determined by adjusting the molecular weight of the polyol as a raw material, the mixing ratio of the polyol and the polyisocyanate, and the like.

  The main component containing the polyol component is an embodiment containing only the specific urethane polyol, that is, it is preferable to use substantially only the specific urethane polyol as the main component containing the polyol component. In addition to the polyol, a polyol compatible with the urethane polyol and having no urethane bond may be contained. In this case, the polyol having no urethane bond is not particularly limited, and the above-mentioned raw material polyol for synthesizing the urethane polyol can be used. Further, when a polyol having no urethane bond is contained in the main component, the content of the urethane polyol in the main component is preferably 50% by mass or more, more preferably 80% by mass or more. If the content of the urethane polyol in the main agent is less than 50% by mass, the content of the urethane polyol is relatively small, and the drying time is long.

  The coating film of the golf ball of the present invention, in addition to the above-mentioned resin component and the phosphorus-based stabilizer, further includes an ultraviolet absorber, an antioxidant, a light stabilizer, a fluorescent brightener, an antiblocking agent, a pigment, and the like. An additive that may be contained in the coating film of the general golf ball described above may be contained. It is also a preferred embodiment that the coating film of the golf ball of the present invention is a clear coating film containing substantially no pigment.

  The coating film is formed by applying a coating composition containing the above-mentioned resin component and the phosphorus-based stabilizer, and further, if necessary, a solvent and the above-mentioned additives to the surface of a golf ball body and drying the golf ball. It can be provided on the surface. The coating film may have, for example, a single-layer structure or a multilayer structure, but preferably has a single-layer structure. This is because the coating film of the present invention is excellent in adhesion to a golf ball and durability, so that a single-layer structure can exhibit sufficient coating film performance. The thickness of the coating film is not particularly limited, but is preferably 5 to 20 μm. If the thickness is less than 5 μm, the performance of the coating film cannot be sufficiently exerted. If the thickness is more than 20 μm, the size of the dimples may change and the flight performance may be reduced.

  The structure of the golf ball of the present invention is not particularly limited, and may be, for example, a one-piece golf ball, a two-piece golf ball, a multi-piece golf ball equal to or more than a three-piece golf ball, or a thread-wound golf ball. Particularly, in the case of a golf ball having a cover such as a two-piece golf ball, a multi-piece golf ball, and a thread wound golf ball, as the cover material, an urethane resin such as an ionomer resin, a polyester resin, a thermoplastic urethane resin, or a two-component curable urethane resin. And various resins such as polyamide resins can be used alone or in combination of two or more. In particular, as a cover material, a urethane resin such as a thermoplastic urethane resin or a two-component curable urethane resin, an ionomer resin, or a mixture of a urethane resin and an ionomer resin is 50% by mass or more, more preferably 75% by mass or more, and furthermore It is also a preferred embodiment to use 90% by mass or more. By increasing the content of the urethane resin or the ionomer resin, the durability and shot feeling of the cover can be improved, and the coating film containing the phosphorus-based stabilizer has excellent adhesion to these covers. This is because it shows durability.

  The ionomer resin constituting the cover is an ionomer resin conventionally used as a cover material for golf balls, that is, at least one of carboxyl groups in a copolymer of ethylene and α, β-unsaturated carboxylic acid. Part of which is neutralized with a metal ion, or at least a part of carboxyl groups in a terpolymer of ethylene, an α, β-unsaturated carboxylic acid and an α, β-unsaturated carboxylic acid ester is a metal ion And the like.

  Examples of the metal ions for neutralization include monovalent metal ions such as sodium ion, potassium ion and lithium ion; divalent metal ions such as zinc ion, calcium ion, magnesium ion, copper ion and manganese ion; aluminum ion and neodymium Examples thereof include a trivalent metal ion such as an ion, and a zinc ion is particularly preferable since the bonding strength of the aggregate of the metal ion is large and a decrease in mechanical strength due to dispersion of the crosslinked diene rubber particles is small.

  Specific examples of the ionomer resin include Himilan 1605 (trade name of sodium ion neutralized ethylene-methacrylic acid copolymer type ionomer resin) and Himilan 1707 (sodium ion neutralized ethylene-methacrylic acid copolymer) manufactured by Du Pont-Mitsui Polychemicals, Inc. Himilan 1706 (trade name of zinc ion neutralized ethylene / methacrylic acid copolymer type ionomer resin), Himilan AM7315 (trade name of zinc ion neutralized ethylene / methacrylic acid copolymer type ionomer resin) Himilan AM7317 (trade name of zinc ion neutralized ethylene-methacrylic acid copolymer ionomer resin), Himilan 1555 (trade name of sodium ion neutralized ethylene-methacrylic acid copolymer ionomer resin), c Milan 1557 (trade name of zinc ion neutralized ethylene-methacrylic acid copolymer ionomer resin), Iotech 8000 manufactured by Exxon Chemical Co., Ltd. (trade name of sodium ion neutralized ethylene-methacrylic acid copolymer ionomer resin), Iotech 7010 (Trade name of zinc ion neutralized ethylene-methacrylic acid copolymer ionomer resin), Surlyn 7930 (trade name of lithium ion neutralized ethylene-methacrylic acid copolymer ionomer resin), Surlyn 9945 (trade name of zinc ion Japanese ethylene-methacrylic acid copolymer-based ionomer resin), Surlyn 8945 (trade name of sodium ion-neutralized ethylene-methacrylic acid copolymer-based ionomer resin) and the like.

  Examples of the urethane resin constituting the cover include a two-part curable urethane resin obtained by curing an isocyanate group-terminated urethane prepolymer with an aromatic polyamine, or a thermoplastic urethane resin. The polyisocyanate component and the polyol component of the urethane resin are not particularly limited, and the same polyisocyanate and polyol as described above can be used as the urethane resin component for a coating film. Urethane resin using PTMG is preferable. The aromatic polyamine is not particularly limited as long as it is a compound in which at least two or more amino groups are directly or indirectly bonded to an aromatic ring, and examples thereof include phenylenediamine, toluenediamine, and diethyltoluene. A type in which an amino group such as a diamine is directly bonded to an aromatic ring; a type in which an amino group such as dimethylthiotoluenediamine is bonded to an aromatic ring via a sulfide bond; An amino group such as xylylenediamine is lower A type linked to an aromatic ring via an alkylene group; 4,4′-diaminodiphenylmethane and derivatives thereof;

  Further, the coating film containing the phosphorus-based stabilizer exhibits excellent adhesion and durability to a one-piece golf ball obtained by vulcanizing a rubber composition. Examples of the rubber composition include a rubber composition containing a diene rubber as a base rubber, a co-crosslinking agent, and a crosslinking initiator. As the diene rubber, it is particularly preferable to use high cis polybutadiene having a cis bond advantageous for repulsion of 40% or more, preferably 70% or more, more preferably 90% or more. As the co-crosslinking agent, an α, β-unsaturated carboxylic acid having 3 to 8 carbon atoms or a metal salt thereof, preferably a metal salt of acrylic acid or methacrylic acid is used. As the metal, zinc, magnesium, Calcium, aluminum and sodium are preferred, and zinc is more preferably used.

  The use amount of the co-crosslinking agent is preferably 20 to 50 parts by mass per 100 parts by mass of the base rubber. As the crosslinking initiator, an organic peroxide is preferably used. Specifically, dicumyl peroxide, 1,1-bis (t-butylperoxy) -3,5-trimethylcyclohexane, 2,5-dimethyl-2,5-di (t-butylperoxy) hexane, Organic peroxides such as di-t-butyl peroxide are exemplified, and among them, dicumyl peroxide is preferably used. The compounding amount of the organic peroxide is 0.2 parts by mass or more, more preferably 0.3 parts by mass or more, and 1.5 parts by mass or less, more preferably 1 part by mass, based on 100 parts by mass of the base rubber. It is desirably not more than 0.0 parts by mass. Heat press molding conditions for the rubber composition may be appropriately set in accordance with the rubber composition, but it is usually preferable to heat the composition at 160 ° C. for 30 minutes.

  The cover material and the rubber composition described above may further contain a specific gravity adjuster such as zinc oxide or barium sulfate, an antioxidant, a pigment such as titanium oxide, a color powder, or the like.

  Next, a method for manufacturing the golf ball of the present invention will be described by taking an example of a two-piece golf ball as an example, but the present invention is not limited to such a manufacturing method. As the core of the two-piece golf ball, a conventionally known core can be used.For example, a core rubber composition containing a diene rubber as a base rubber, a co-crosslinking agent, and a crosslinking initiator is hot-pressed. It is preferably formed by molding. As the rubber composition for the core, for example, the same rubber composition as described above for the one-piece golf ball can be used, and further, a specific gravity adjusting agent such as zinc oxide or barium sulfate, an antioxidant, and a colorant. Powder and the like can be appropriately blended. Heat press molding conditions of the rubber composition for the core may be appropriately set according to the rubber composition, but are usually heated at 130 to 200 ° C for 10 to 60 minutes, or at 130 to 150 ° C for 20 to 40 minutes. After heating, it is preferable to perform two-stage heating at 160 to 180 ° C. for 5 to 15 minutes.

  The core obtained as described above is covered with the above-described cover material to produce a golf ball body. When a golf ball body is manufactured by covering a core with a cover material, a depression called a dimple is usually formed on the surface. Further, the surface of the golf ball body may be subjected to a polishing treatment such as a sand blast treatment in order to further improve the adhesion to the coating film.

  Hereinafter, the present invention will be described in detail with reference to examples. However, the present invention is not limited to the following examples, and changes in a range that does not depart from the gist of the present invention and all of the embodiments are described below. Included in the range.

[Evaluation method]
(1) Discoloration resistance After the golf ball was manufactured, an outdoor exposure test was performed for 6 months, and the discoloration of the coating film was visually observed.
Evaluation criteria ○: No discoloration, ×: Discoloration

(2) Adhesion and durability against impact A swing iron manufactured by True Temper Co., Ltd. was equipped with a 5-iron, and was repeatedly impacted 150 times at a head speed of 34 m / sec. Was evaluated for adhesion and durability.
Evaluation criteria for coating film A: No peeling of coating film.
：: The peeled area of the coating film is 5% or less of the area of the entire coating film.
Δ: The peeled area of the coating film is more than 5% and 20% or less of the area of the entire coating film.
X: The peeling area of the coating film is more than 20% of the area of the entire coating film.
Evaluation criteria for marks A: No peeling of marks.
：: The peeled area of the mark is 5% or less of the area of the entire mark.
X: The peeled area of the mark is more than 20% of the area of the entire mark.

(3) Adhesion and durability against brushing cleaning A golf ball is put into a potato pillar whose inner surface is covered with a brush, brushing cleaning is performed for one hour, the peeling state of the coating film and marks is observed, and the following evaluation criteria are used. , Adhesion and durability were evaluated.
Evaluation criteria for coating film A: No peeling of coating film.
：: The peeled area of the coating film is 5% or less of the area of the entire coating film.
Δ: The peeled area of the coating film is more than 5% and 20% or less of the area of the entire coating film.
X: The peeling area of the coating film is more than 20% of the area of the entire coating film.
Evaluation criteria for marks A: No peeling of marks.
Good: The peeled area of the mark is 5% or less of the area of the entire mark.
Δ: The peeled area of the mark is more than 5% to 20% or less of the entire area of the mark.
X: The peeled area of the mark is more than 20% of the area of the entire mark.

[Production of one-piece golf ball body]
The rubber composition shown in Table 1 was kneaded and pressure-formed at 160 ° C. for 30 minutes to obtain a one-piece golf ball body.

Polybutadiene rubber: BR11 manufactured by JSR Corporation

[Creating a two-piece golf ball body]
(1) Preparation of core A rubber composition for a core having the composition shown in Table 2 was kneaded and heated and pressed at 160 ° C. for 13 minutes in upper and lower molds having hemispherical cavities to obtain a spherical core having a diameter of 39.3 mm. Was.

Polybutadiene rubber: BR11 manufactured by JSR Corporation

(2) Manufacture of cover Two-piece golf having a cover layer formed by coating the various cover compositions shown in Tables 3 and 4 on the core obtained as described above and having a diameter of 42.7 mm. A ball body was manufactured.

Himilan 1605: Sodium ion neutralized ethylene-methacrylic acid copolymer ionomer resin manufactured by Mitsui Dupont Polychemical Co., Ltd. Himilan 1706: Zinc ion neutralized ethylene-methacrylic acid copolymer ionomer resin manufactured by Mitsui Dupont Polychemical Co., Ltd. Himilan 1707: Sodium ion neutralized ethylene-methacrylic acid copolymer ionomer resin manufactured by Mitsui DuPont Polychemicals, Inc.

Elastollan XNY90A: BASF Polyurethane Elastomers Ltd. of 4,4'-dicyclohexylmethane diisocyanate (H ₁₂ MDI: hydrogenated MDI) polyurethane-based thermoplastic elastomer Elastogran run using XNY97A: manufactured by BASF Polyurethane Elastomers Ltd. 4,4'-dicyclohexylmethane diisocyanate: thermoplastic polyurethane elastomer was used (H ₁₂ MDI hydrogenated MDI) Pebax 5533SN00: Elf Atochem Japan Co., Ltd. thermoplastic polyether polyamide elastomer

[Formation of mark and coating film]
On the surface of the obtained golf ball body, a mark “X” having a width of 8 mm × a height of 8 mm × a line width of 2 mm was printed with a pad stamp using the mark printing ink composition shown in Table 5, and then prepared as follows. The coating composition was applied with an air gun and dried at 40 ° C. to form a mark and a coating film (thickness: 10 μm) on the surface of the golf ball. Tables 6 to 8 show the results of evaluating the obtained golf balls for discoloration resistance, adhesion, and durability.

[Preparation of coating composition]
(1) Main agent: Preparation of urethane polyol 116 parts by mass of PTMG650 and 16 parts by mass of 1,2,6-hexanetriol are dissolved in 120 parts by mass of a solvent (toluene and methyl ethyl ketone), and dibutyltin dilaurate is added to the entire main agent. It was added so as to be 0.1% by mass. While maintaining the polyol at 80 ° C, 48 parts by mass of isophorone diisocyanate was added dropwise to prepare a urethane polyol (solid content: 60% by mass, hydroxyl value: 87 mgKOH / g, molecular weight: 7850).
(2) Curing agent: isophorone diisocyanate (Sumitomo Bayer Urethane)
(3) Compounding ratio: NCO of curing agent / OH of main agent = 1.2 (molar ratio)
(4) The following two-component curable urethane resin paint was added with the following phosphorus-based stabilizer, light stabilizer, ultraviolet absorber, fluorescent brightener, and the like to prepare a paint composition. In addition, the addition amounts of the phosphorus-based stabilizer, the light stabilizer, the ultraviolet absorber, the fluorescent whitening agent and the like to 100 parts by mass of the urethane resin component are also shown in Tables 6 to 8.
Phosphorus-based stabilizer: “GSY-P101 (tetrakis (2,4-di-t-butyl-5-methylphenyl) [1,1′-biphenyl] -4,4′-diylbisphosphonite, manufactured by API Corporation) ) "
Light stabilizer: "Sanol LS770" manufactured by Sankyo
UV absorber: Ciba Geigy "Tinuvin 900"
Fluorescent brightener: "Ubitex OB" manufactured by Ciba-Geigy

  Table 6 shows the evaluation results of the coating film properties of the one-piece golf balls.

  Golf ball No. 1 to 3 are cases where the coating film provided on the golf ball surface contains 0.06 to 4.5 parts by mass of the phosphorus-based stabilizer with respect to 100 parts by mass of the urethane resin component. It can be seen that they have excellent durability, durability, and adhesion. Further, it can be seen that as the content of the phosphorus-based stabilizer is increased, the adhesion and durability of the coating film are improved. On the other hand, golf ball No. No. 11 was a case where the coating film did not contain a phosphorus-based stabilizer, and none of the discoloration resistance, durability and adhesion were good. In addition, golf ball No. No. 12 is a case where the content of the phosphorus-based stabilizer contained in the coating film is as small as 0.03 parts by mass with respect to 100 parts by mass of the urethane resin component. Golf ball No. 1 containing 0.06 to 4.5 parts by mass of a phosphorus-based stabilizer. As compared with Nos. 1 to 3, not only the discoloration resistance but also the adhesion and durability of the coating film were reduced. Golf ball No. No. 13 is a case where the content of the phosphorus-based stabilizer is as much as 7 parts by mass relative to 100 parts by mass of the urethane resin component. Although there was no discoloration of the coating over time, the adhesion and durability of the coating were significantly reduced.

  From these results, by adding an appropriate amount of a phosphorus-based stabilizer to the coating film, the discoloration resistance of the coating film is improved, and excellent adhesion to a one-piece golf ball obtained by vulcanizing the rubber composition is obtained. It can be seen that a coating film exhibiting properties and durability was obtained.

  Table 7 shows the evaluation results of the coating film properties of the golf ball having the cover using the ionomer resin as the cover material. Golf ball No. Nos. 4 to 6 are cases where the coating film provided on the golf ball surface contains 0.06 to 4.5 parts by mass of the phosphorus-based stabilizer with respect to 100 parts by mass of the urethane resin component, and It can be seen that the adhesiveness and durability of the coating film are improved as the content of the phosphorus-based stabilizer is increased.

  Golf ball No. No. 14 was a case where the coating film did not contain a phosphorus-based stabilizer, and none of the discoloration resistance, durability and adhesion were good. In addition, golf ball No. No. 15 is a case where the content of the phosphorus-based stabilizer contained in the coating film is as small as 0.03 parts by mass with respect to 100 parts by mass of the urethane resin component. The properties and durability also decreased. Golf ball No. No. 16 is a case where the content of the phosphorus-based stabilizer is as much as 7 parts by mass with respect to 100 parts by mass of the urethane resin component. Although there was no discoloration of the coating over time, the adhesion and durability of the coating were significantly reduced.

  From these results, by adding an appropriate amount of a phosphorus-based stabilizer to the coating film, the discoloration resistance of the coating film is improved, and excellent adhesion and durability to the cover using an ionomer resin as the cover material are obtained. It can be seen that a coating film showing

  Table 8 shows the evaluation results of the coating properties of golf balls having covers using urethane resin as the cover material. Golf ball No. Nos. 7 to 9 are cases where the coating film provided on the golf ball surface contains 0.06 to 4.5 parts by mass of a phosphorus-based stabilizer with respect to 100 parts by mass of the urethane resin component. On the other hand, golf ball No. No. 17 does not contain a phosphorus-based stabilizer. No. 18 is a case where the content of the phosphorus-based stabilizer was too small. No. 19 is the case where the content of the phosphorus-based stabilizer is excessive. As in the case of the cover using the Ainomao resin, the golf ball No. Nos. 7 to 9 are excellent in discoloration resistance and show excellent adhesion and durability to a cover using a urethane resin.

Claims (5)

  A golf ball provided with a coating film on a golf ball surface, wherein the coating film contains 0.05 to 5 parts by mass of a phosphorus-based stabilizer with respect to 100 parts by mass of a resin component. Golf ball to play.   The golf ball according to claim 1, wherein the phosphorus-based stabilizer is a phosphorous compound, a hypophosphorous compound, or a derivative thereof.   The golf ball according to claim 1, wherein the resin component of the coating film is a urethane resin.   The golf ball according to any one of claims 1 to 3, wherein the golf ball has a cover, and uses an ionomer resin or a urethane resin as a cover material.   The golf ball according to claim 1, wherein the coating has a single-layer structure.