JP2002119615A - Thermoplastic resin composition for golf ball cover material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a thermoplastic elastomer composition for a golf ball which has an excellent wear-resistance and repulsive elasticity. SOLUTION: This thermoplastic resin composition for the golf ball cover material contains 100 pts.wt. of an aromatic vinyl compound-conjugate diene compound based copolymer, 0 to 240 pts.wt. of a rubber softener, 0 to 100 pts.wt. of a peroxide crosslinking type olefin based resin, 0 to 100 pts.wt. of a peroxide resoluble type olefin based resin, 0 to 30 pts.wt. of a liquid polybutadiene, 0 to 150 pts.wt. of an unsaturated glycidyl compound, 0 to 15 pts.wt. of an unsaturated carboxylic acid, 0 to 15 pts.wt. of a (meth)acrylate based compound having a hydroxyl group, and also, 0 to 3.5 pts.wt. of an organic peroxide based on the total of 100 pts.wt. of the above mentioned substances, and in addition, 0 to 1,500 pts.wt. of at least one compound which is selected from the group comprising polyester, polyurethane, polyamide, and polymethylpentene.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a golf ball having improved injection moldability while maintaining the basic properties required for a golf ball, such as rebound resilience and wear resistance, of a conventional golf ball cover material. And a thermoplastic composition for a golf ball cover material.

[0002]

2. Description of the Related Art Conventionally, trans-polyisoprene (balata) has been used as a cover material for golf balls.
However, the balata cover ball has a drawback that the cover surface is easily damaged at the time of a shot, and also has a problem in price and moldability.

[0003] For this reason, various cover materials using a thermoplastic polyurethane elastomer have been proposed to solve the above-mentioned drawbacks of balata (US Pat. No. 339).
No. 5109, No. 4248432, No. 444228
No. 2, JP-A-11-9721, etc.).

In addition to the above-mentioned components, studies have been made on styrene-butadiene-block polymer (SB).
S), styrene / isoprene-block polymer (SI
Polystyrene-based thermoplastic elastomers such as S) and their hydrogenated products are rich in flexibility, have good rubber elasticity at room temperature, and the thermoplastic elastomer compositions obtained therefrom have excellent processability. . However, it has been found that golf balls formed by these methods are inferior in wear resistance and scratch resistance.

[0005]

When these thermoplastic polyurethane elastomers are used as a cover material, the injection moldability of the balata is improved while maintaining the basic properties required for golf ball cover materials such as rebound resilience and wear resistance. Although a cover material for a golf ball having improved is obtained, it is still insufficient in moldability, particularly in control of molding cycle and releasability during injection molding, and sink of a molded product surface. In particular, the composition disclosed in Japanese Patent Application Laid-Open No. 11-9721 is insufficient in fluidity at the time of injection molding, and efficiently produces a golf ball that requires a perfect sphere due to poor releasability. It is difficult.

Accordingly, the present invention provides an excellent golf ball having a superior wear resistance and rebound resilience while maintaining the injection moldability of a cover material containing a thermoplastic polyurethane elastomer as a main component. The purpose is to give an effect.

[0007]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present inventor has developed a golf club having a significantly improved injection moldability while maintaining excellent wear resistance and rebound resilience. Intensive studies have been conducted to obtain a thermoplastic resin composition for a ball cover material, and (a) 100 parts by weight of at least one selected from the group consisting of (a) an aromatic vinyl compound-conjugated diene compound copolymer and / or a hydrogenated product thereof; b) 0 to 240 parts by weight of a non-aromatic rubber softener, (c) 0 to 100 parts by weight of a peroxide-crosslinked olefin resin, and / or a copolymer thereof, (d) a peroxide-decomposable olefin resin, And / or 0 to 100 parts by weight of a copolymer thereof,
(E) 0 to 30 parts by weight of liquid polybutadiene, (f) 0 to 15 parts by weight of an unsaturated glycidyl compound or a derivative thereof,
(G) 0 to 15 parts by weight of an unsaturated carboxylic acid or a derivative thereof, (h) 0 to 15 parts by weight of a (meth) acrylate compound having a hydroxyl group, and (j) organic peroxides (a) to (h). 0 to 3.5 based on 100 parts by weight in total
Parts by weight, further selected from the group consisting of (i) a polyester polymer or a copolymer thereof, a polyurethane polymer or a copolymer thereof, a polyamide polymer or a copolymer thereof, a polymethylpentene polymer or a copolymer thereof. Thus, a thermoplastic resin composition for a golf ball cover material of the present invention comprising 0 to 1500 parts by weight of at least one compound selected from the group consisting of 0 to 1500 parts by weight of at least one compound obtained.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, each component of the resin composition of the present invention will be described in detail.

(A ) Aromatic vinyl compound-conjugated diene formation
Component copolymer and / or hydrogenated product thereof Component (a) in the present invention comprises (a-1) a block copolymer of an aromatic vinyl compound and a conjugated diene compound, or a hydrogenated product thereof; And / or at least one selected from the group consisting of a random copolymer of an aromatic vinyl compound and a conjugated diene compound, or a hydrogenated product. Examples of the aromatic vinyl compound in the component (a) include styrene, t-butylstyrene, α-methylstyrene, and p
One or more of methyl-styrene, divinylbenzene, 1,1-diphenylstyrene, N, N-diethyl-p-aminoethylstyrene, vinyltoluene, p-tert-butylstyrene, and the like. Styrene is preferred. Examples of the conjugated diene compound include butadiene, isoprene, 1,3-pentadiene,
One or more kinds are selected from 2,3-dimethyl-1,3-butadiene and the like, and among them, butadiene, isoprene and a combination thereof are preferable.

Component (a-1): a block copolymer; and
Component (a-1) of the present invention comprises at least one polymer block A mainly composed of an aromatic vinyl compound and at least one polymer block B mainly composed of a conjugated diene compound.
And a mixture obtained by hydrogenating the block copolymer, or a mixture thereof, for example, AB, ABA, BABA, AB- A
And an aromatic vinyl compound-conjugated diene compound block copolymer having a structure such as -BA or a hydrogenated product thereof. The (hydrogenated) block copolymer (hereinafter, the (hydrogenated) block copolymer means a block copolymer and / or a hydrogenated block copolymer) is obtained by mixing an aromatic vinyl compound with 5 to 50 parts. % By weight, preferably 20 to 40% by weight. The polymer block A mainly composed of an aromatic vinyl compound is preferably
The content of the aromatic vinyl compound is 50 to 100% by weight, preferably 70% by weight or more. The polymer block B mainly composed of a conjugated diene compound is preferably a conjugated diene compound having 5
It is preferably from 0 to 100% by weight, preferably 70% by weight or more and hydrogenated. It is preferable that at least 70% or more of the aliphatic double bond in the conjugated diene compound is hydrogenated. When there are two or more polymer blocks A mainly composed of an aromatic vinyl compound or two or more polymer blocks B mainly composed of a (hydrogenated) conjugated diene compound, they have different structures even if they have the same structure. There may be.

The weight average molecular weight of the (hydrogenated) block copolymer of the present invention having the above-mentioned structure is preferably 5,000 to 1,500,000, more preferably 1 to 1.
The range is from 0000 to 550,000. The molecular weight distribution (ratio (Mw / Mn) of weight average molecular weight (Mw) to number average molecular weight (Mn)) is preferably 10 or less, more preferably 5 or less, and more preferably 2 or less. The molecular structure of the (hydrogenated) block copolymer may be linear, branched, radial, or any combination thereof.

Numerous methods have been proposed as methods for producing these block copolymers. Representative methods include, for example, a method described in Japanese Patent Publication No. 40-23798, which uses a lithium catalyst or Ziegler catalyst. It can be obtained by performing block polymerization in an inert solvent using a type catalyst. The hydrogenated block copolymer can be obtained by hydrogenating the block copolymer obtained by the above method in an inert solvent in the presence of a catalyst.

Specific examples of the (hydrogenated) block copolymer include SBS, SIS, SEBS, SEPS, and SIB.
S and its hydrogenated products can be mentioned. In the present invention, a particularly preferred (hydrogenated) block copolymer is a polymer block A mainly composed of styrene and a polymer block mainly composed of isoprene, and 70 to 100% by weight of isoprene is 1,4-.
Having a weight average molecular weight of 50,000 to 55, comprising a polymer block B having a microstructure and having at least 70% of the aliphatic double bonds based on the isoprene hydrogenated.
It is a 000 hydrogenated block copolymer. More preferably, 90 to 100% by weight of isoprene is the above hydrogenated block copolymer having a 1,4-microstructure.

Component (a-2): a random copolymer, and / or
Or a hydrogenated product thereof The component (a-2) random copolymer of the present invention and / or a hydrogenated product thereof is a random copolymer of a conjugated diene compound and an aromatic vinyl compound of 50% by weight or less. Has a number average molecular weight of 5,000 to 1,000,000, a polydispersity (Mw / Mn) value of 10 or less,
In addition, the conjugated diene moiety has a vinyl bond content such as 1,2 bond or 3,4 bond of 5% or more, and preferably 20 to 90%. If it is less than 5%, the resulting molded article has a hard feel and does not meet the purpose of the present invention. Here, the content of the aromatic vinyl compound constituting the component (a-2) is 50% by weight or less, and preferably 5 to 35% by weight. If the content exceeds 50% by weight, the resulting molded article has a hard feel, which does not meet the purpose of the present invention. As the aromatic vinyl compound in the component (a-2), those similar to the component (a-1) are used. The aromatic vinyl compounds are randomly linked, and can be found in Korsov [I. M. Kolth
off, J.M. Polymer Sci. , Vol1
p. 429 (1946)], the content of the block-shaped aromatic vinyl compound is 1% of the total bound aromatic vinyl compound.
0% by weight or less, preferably 5% by weight or less. Also,
As the conjugated diene compound, those similar to the aforementioned component (a-1) are used. For example, butadiene, isoprene, 2,3-
Dimethyl butadiene, pentadiene and the like can be mentioned.
Preferably, at least 90% of the aliphatic double bonds based on the conjugated diene compound are hydrogenated.

(B) Component Softener for Non-Aromatic Rubber As the component (b) of the present invention, a non-aromatic mineral oil or a liquid or low molecular weight synthetic softener can be used.

The non-aromatic rubber softener used as component (b) of the present invention is a paraffinic or naphthenic or a mixture thereof. The use of an aromatic softening agent is not preferred because its use makes the component (a) soluble and inhibits the cross-linking reaction, so that the physical properties of the obtained composition cannot be improved. The component (b) is preferably a paraffinic one, and more preferably a paraffinic one that does not contain an aromatic ring component.

These non-aromatic rubber softeners have a dynamic viscosity at 37.8 ° C. of 20 to 500 cS.
t, pour point is -10 to -15 ° C, flash point (COC) is 1
Indicates 70 to 300 ° C.

The amount of the component (b) is 100 parts (a).
The upper limit is 240 parts by weight based on parts by weight. There is no particular lower limit. If the amount exceeds the upper limit, bleed-out of the softener tends to occur, which may give tackiness to the final product, and also deteriorates mechanical properties.

Component (c) Peroxide-crosslinked olefin
High-density polyethylene (low-pressure polyethylene), low-density polyethylene (high-pressure polyethylene), linear low-density polyethylene , and / or its copolymer peroxide-crosslinked olefin-based resin and / or its copolymer. Polyethylene such as polyethylene (a copolymer of ethylene and a small amount, preferably 1 to 10 mol% of an α-olefin such as butene-1, hexene-1, octene-1), ethylene-propylene copolymer, ethylene-vinyl acetate copolymer, ethylene One or more selected from acrylic ester copolymers and the like are preferably used. Particularly preferred are produced with a metallocene catalyst (single site catalyst), a density of 0.90 g / cm ³ or less of ethylene-octene copolymers or density 0.90 g / cm ³ or more ethylene-hexene copolymers.

There is no particular lower limit for the amount of component (c).
The upper limit is 100 parts by weight based on 100 parts by weight of component (a). If the upper limit is exceeded, bleed-out of the rubber softener (b) tends to occur.

Component (d) Peroxide decomposable olefin
The peroxide-decomposable olefin-based resin and / or its copolymer of the olefin-based resin and / or its copolymer component (d) is generally a homopolymer,
Any of a polypropylene compound composed of a block copolymer, a random copolymer and the like can be used. For example, copolymers of propylene with other small amounts of α-olefins such as ethylene, 1-butene, 1-hexene, 4-methyl-1-pentene, and the like are preferred.

The component (d) of the present invention has an effect of improving the rubber dispersion in the obtained composition and improving the appearance of a molded article. The upper limit of the amount of component (d) is component (a) 1.
100 parts by weight to 100 parts by weight. There is no particular lower limit. 1
When the amount exceeds 00 parts by weight, the flexibility and rubber elasticity of the obtained elastomer composition are deteriorated.

Component (e) Liquid polybutadiene The liquid polybutadiene has a main chain having a vinyl bond having a 1,2-bond, a trans-1,4-bond, a cis-1,4-bond.
It is a liquid polymer that is transparent at room temperature and consists of 4-bonds. Here, the 1,2-bond is preferably 30% by weight or less, and when the 1,2-bond exceeds 30% by weight,
This is not preferred because the low-temperature properties of the resulting composition are reduced.

The number average molecular weight of the liquid polybutadiene is:
The upper limit is preferably 5,000, more preferably 4,000.
0, and the lower limit is preferably 1,000, more preferably 3,000. If the amount is less than the lower limit, the heat-deformation resistance of the obtained composition decreases, and if it exceeds the upper limit, the compatibility of the obtained composition decreases.

Further, the liquid polybutadiene is preferably a copolymerizable compound having one or more groups selected from an epoxy group, a hydroxyl group, an isocyanate group and a carboxyl group. Among them, those having a hydroxyl group and an unsaturated double bond are particularly preferred. Commercially available products include, for example, R-45HT (trademark) manufactured by Idemitsu Petrochemical Co., Ltd.
Is mentioned.

The amount of component (e) is 100 parts (a)
The upper limit is 30 parts by weight based on parts by weight. There is no particular lower limit, but if it exceeds the upper limit, the mechanical properties of the composition deteriorate.

Component (f) unsaturated glycidyl compound or
The derivative of the unsaturated glycidyl compound or derivative thereof is used as a modifier, preferably a glycidyl compound having an unsaturated group capable of copolymerizing with an olefin and a glycidyl group in the molecule, and particularly preferably glycidyl. Methacrylate (GMA) is used. The modifying agent preferably decomposes the soft component of the hydrogenated block copolymer in component (a), the peroxide-crosslinked olefin resin of component (c), and / or the copolymer thereof, and the peroxide decomposition of component (d). Type olefin resin, and / or
Alternatively, it is considered that the copolymer is modified.

The amount of component (f) is 100 parts
The upper limit is 15 parts by weight based on parts by weight. There is no particular lower limit. If the ratio exceeds the upper limit, not only the heat deformation resistance and mechanical properties of the composition are deteriorated, but also the effect of improving the compatibility of the component (i) when blended is not recognized.

Component (g) Unsaturated carboxylic acid or derivative thereof
Conductive unsaturated carboxylic acids or derivatives thereof are those used as modifiers, preferably acrylic acid, methacrylic acid, maleic acid, dicarboxylic acids or derivatives thereof such as acids, halides, amides, imides, anhydrides, esters and the like. No. Particularly preferred is maleic anhydride (MAH)
Is used. Due to the modifier, preferably component (a)
A soft component of the hydrogenated block copolymer, a peroxide-crosslinked olefin resin of component (c), and / or
Alternatively, it is considered that the copolymer thereof and the peroxide-decomposable olefin resin of the component (d) and / or the copolymer thereof are modified.

The amount of component (g) is 100 parts (a).
The upper limit is 15 parts by weight based on parts by weight. There is no particular lower limit, but when it exceeds the upper limit, not only does the composition cause severe yellowing, but also when the component (i) is blended, the effect of improving the compatibility of the component is not recognized.

Component (h) (meth) acryl having a hydroxyl group
Luic acid ester compound component (h) The (meth) acrylic acid ester compound having a hydroxyl group has an effect of improving the compatibility between components (a) and (b). Examples include 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, 2-hydroxypropyl acrylate, 2-hydroxypropyl methacrylate, 3-chloro-2-hydroxypropyl methacrylate, 3-hydroxybutyl acrylate,
Ethyl-2-hydroxyethyl fumarate, 2-hydroxybutyl acrylate, 4-hydroxybutyl acrylate and a polymer, copolymer, or copolymer with another monomer comprising the same can be used. Here, examples of the copolymerizable monomer include ethylene, propylene, styrene, vinyl acetate, and vinyl chloride. Preferably, 2-hydroxyethyl methacrylate is used.

The amount of the component (h) is 100 parts (a).
The upper limit is 15 parts by weight with respect to parts by weight. There is no particular lower limit, but if the amount exceeds the upper limit, a large amount of gas is generated during molding.

(I) component polyester-based polymer, and
/ Or a copolymer thereof, or a polyamide-based polymer, and /
Or a copolymer thereof, or a polyurethane polymer, and / or
Or a copolymer thereof, or a polymethylpentene-based polymer,
And / or copolymer thereof. Polyester-based polymer and its copolymer, polyamide-based polymer and its copolymer, or polyurethane-based polymer and its copolymer, which can be used as component (i) of the present invention. Is not particularly limited, and any polymer or copolymer thereof can be used satisfactorily. The copolymer may be a block copolymer or a graft copolymer. It preferably has elastomeric properties. Commercially available polymers mentioned above can also be used satisfactorily. Particularly preferred are the above-mentioned copolymers.
Further, the above polymers or copolymers may be used alone or in combination. For example, as a polyester-based polymer and its copolymer, the hard component is polyethylene terephthalate or polybutylene terephthalate and the soft component is an aliphatic polyether or aliphatic polyester,
Examples of (co) polymers in which the hard component is polybutylene naphthalate and the soft component is an aliphatic polyether, and polyamide-based polymers and copolymers thereof include 6-nylon, 6,6-nylon, 4,6-nylon, 6,10-nylon or 6,12-nylon;
Block elastomers in which the hard component is made of 6-nylon or 12-nylon and the soft component is made of polyether or polyetherester, and examples of the polyurethane-based polymer and copolymer include lactone-based,
Ester-based or ether-based (co) polymers can be mentioned. Examples of the polymethylpentene polymer or its copolymer include poly-4-methylpentene-1.

The amount of component (i) is 100 parts (a)
There is no particular lower limit for parts by weight. The upper limit is 1500
Not more than parts by weight. When the amount exceeds 1500 parts by weight, the flexibility of the obtained elastomer composition is reduced, and there is no great difference from a polyester-based polymer, a polyamide-based polymer or a polyurethane-based polymer alone. By blending the component (i), the scratch resistance and abrasion resistance of the obtained elastomer composition are remarkably improved. Further, if an elastomer containing the polyurethane polymer, polyamide polymer, polyester polymer, and polymethylpentene polymer is used as a cover material and an intermediate layer for a golf ball composed of an ionomer resin and a polybutadiene core material, Can be crushed and recycled.

Component (j) Organic peroxide In the dynamic crosslinking of the present invention, an organic peroxide is used. As the organic peroxide, for example, dicumyl peroxide, di-tert-butyl peroxide, 2,5-dimethyl-2,5-di- (tert-
Butylperoxy) hexane, 2,5-dimethyl-2,
5-di (tert-butylperoxy) hexyne-3
1,3-bis (tert-butylperoxyisopropyl) benzene, 1,1-bis (tert-butylperoxy) -3,3,5-trimethylcyclohexane,
n-butyl-4,4-bis (tert-butylperoxy) valerate, benzoyl peroxide, p-chlorobenzoyl peroxide, 2,4-dichlorobenzoyl peroxide, tert-butylperoxybenzoate, tert-butylperoxy Examples thereof include isopropyl carbonate, diacetyl peroxide, lauroyl peroxide, and tert-butylcumyl peroxide.

Of these, 2,5-dimethyl-2,5-di- (te) is preferable in terms of odor, coloring and scorch stability.
Most preferred are rt-butylperoxy) hexane, 2,5-dimethyl-2,5-di- (tert-butylperoxy) hexyne-3,1,3-bis (tert-butylperoxyisopropyl) benzene.

The amount of peroxide is not particularly limited with respect to 100 parts by weight of the composition comprising components (a) to (h) at the time of addition of the peroxide, but the upper limit is not more than 3.5 parts by weight. It is. If the amount exceeds 3.5 parts by weight, the crosslinking proceeds excessively, and the dispersion of the crosslinked product becomes poor.

Crosslinking Aid In the present invention, a crosslinking aid is preferably used for dynamic crosslinking. Examples of the crosslinking assistant include polyvinyl monomers such as divinylbenzene and triallyl cyanurate, or ethylene glycol dimethacrylate, diethylene glycol dimethacrylate, triethylene glycol dimethacrylate, polyethylene glycol dimethacrylate, trimethylolpropane trimethacrylate, and allyl. Examples include polyfunctional methacrylate monomers such as methacrylate. By using such a compound, a uniform and efficient crosslinking reaction can be expected. Among them, triethylene glycol dimethacrylate is effective because it is easy to handle and works as a dispersing aid.

The amount of the crosslinking aid used is preferably about 2 to 2.5 times the amount of the peroxide. Although there is no particular lower limit, composition 1 comprising components (a) to (h)
If the added amount exceeds 10 parts by weight with respect to 00 parts by weight, the crosslinking efficiency is reduced.

The composition of the present invention may contain, in addition to the above essential components, various antiblocking agents, sealant improvers, heat stabilizers, antioxidants, ultraviolet absorbers, lubricants, crystal nuclei, depending on the intended use. Agents, coloring agents, inorganic fillers, foaming agents (organic,
(Inorganic type) and the like. The optionally used antioxidant includes 2,6-di-tert-
p-butyl-p-cresol, 2,6-di-tert-
Butylphenol, 2,4-dimethyl-6-tert-
Butylphenol, 4,4-dihydroxydiphenyl,
Tris (2-methyl-4-hydroxy-5-tert-
There are phenolic antioxidants such as butylphenyl) butane, phosphite antioxidants and thioether antioxidants. Among them, phenolic antioxidants and phosphite antioxidants are preferred.

The thermoplastic resin composition for a golf ball cover material of the present invention can be produced, for example, by the following steps. The components (a) to (j) and the optional components may be kneaded all at once, but more preferably by the following method.
First, components other than the component (i) are kneaded under heating. In the case of crosslinking, a crosslinking aid is preferably added. As the kneading method, a method usually used for rubber, plastics and the like can be used satisfactorily. For example, a single-screw extruder, a twin-screw extruder, a roll, a Banbury mixer, various kneaders and the like are used. By this step, a composition in which each component is uniformly dispersed can be obtained.

When adding the component (i), the component (i) is then added to the composition obtained in the above step and kneaded. The kneading can be generally performed using a single-screw extruder, a twin-screw extruder, a roll, a Banbury mixer, various kneaders, or the like. In this step, the reaction is completed at the same time as the dispersion of each component further proceeds. Conveniently, component (i) is side-fed and continuously performed with the above steps. It is also possible to dry blend the composition obtained in the above step with component (i) and to perform injection molding.

As a kneading method, it is preferable to use a twin screw extruder or a Banbury mixer having an L / D of 47 or more, since all the steps can be continuously performed. In addition, for example, when kneading with a twin-screw extruder, if the number of rotations of the screw is 80 to 350 rpm, each component has good dispersion and good properties can be obtained.

[0044]

The present invention will be described in detail below with reference to examples and comparative examples. The amounts in the table mean parts by weight unless otherwise specified.

The following components were used as the components in the examples. Component (a-1-1): hydrogenated block copolymer Septon 2002 manufactured by Kuraray Co., Ltd. Styrene content: 30% by weight Isoprene content: 70% by weight Number average molecular weight (Mn): 55,000 Weight average molecular weight ( Mw): 60,000 Mw / Mn: 1.09 Hydrogenation rate: 90% or more Component (a-1-2): Hydrogenated block copolymer Septon 4077 manufactured by Kuraray Styrene content: 30% by weight of isoprene Content: 70% by weight Number average molecular weight (Mn): 260,000 Weight average molecular weight (Mw): 320,000 Mw / Mn: 1.23 Hydrogenation rate: 90% or more Component (a-2): hydrogenated random Copolymer (SBR) Dynalon 1320P (trademark) manufactured by JSR Styrene content: 10% by weight Number average molecular weight (Mn): 300,000 Mw / Mn: 1.1 Hydrogenation rate More than 90%

Component (b): Non-aromatic rubber softener Diana Process Oil PW-90 manufactured by Idemitsu Kosan Co., Ltd. Type: paraffinic oil Weight average molecular weight: 540 Content of aromatic component: 0.1% or less Component (d) ): Peroxide-decomposable olefin resin polypropylene, BC03C (trademark), manufactured by Mitsubishi Chemical Corporation Component (e): liquid polybutadiene R-45HT (trademark), manufactured by Idemitsu Petrochemical Co., Ltd. Hydroxyl group as a functional group (acrylic first class) And a copolymerizable unsaturated double bond (1,4 bonds: 80%). Number average molecular weight: 2800 Component (f): glycidyl methacrylate manufactured by Kanto Chemical Co., Ltd.

Component (g): maleic anhydride manufactured by Kanto Chemical Co., Ltd. Component (h): (meth) acrylate compound having a hydroxyl group 2-hydroxyethyl methacrylate (HEMA), light ester H0 (trademark), Kyoeisha Chemical Component (i): Thermoplastic polyurethane resin Component (i-1) Pandex T-8180 (trade name) manufactured by DIC Bayer Polymer Co., Ltd. Component (i-2) Pandex T manufactured by DIC Bayer Polymer Co., Ltd. -7890 (trademark)

Component (j): Organic peroxide Perhexa 25B (2,5-dimethyl- manufactured by NOF Corporation)
2,5-di (t-butyl peroxide) hexane) Crosslinking aid: NK ester IND (2-methyl- manufactured by Shin-Nakamura Chemical Co., Ltd.)
1,8-octanediol dimethacrylate (85
%), 1,9-nonanediol dimethacrylate (15%
%) Mixture)

Comparative Component (1) SEBS Tuftec M1913 (trade name) manufactured by Asahi Kasei Kogyo Co., Ltd. Styrene content: 30% by weight Butadiene content: 70% by weight Melt flow rate (JIS K7210 230 ° C.)
2.16 kg): 5 g / 10 min Comparative component (2) SEBS Tuftec H1051 (trade name) manufactured by Asahi Kasei Kogyo Co., Ltd. Styrene content: 40% by weight Butadiene content: 60% by weight Melt flow rate (JIS K7210 230 ° C.)
2.16 kg): 0.8 g / 10 min The resin composition thus obtained was evaluated by the following method.

Evaluation method 1) Rebound resilience According to BS903, a 4 mm thick pressed sheet was used as a test piece. Good rebound resilience of 60% or more 2) Taber abrasion amount conforms to JIS K 7204 A 2 mm thick pressed sheet was used for the test piece, and the abrasion wheel H-2 was used.
The wear mass after 2,1000 rotations was measured. A Taber abrasion of 200 or less is good. 3) Moldability A 300 ton × 2 mm thick sheet is molded under predetermined conditions using a 120-ton injection molding machine. 3-1) Transferability The transferability of the mold surface is excellent. : Extremely good ○: Excellent △: Partial sink marks ×: Defects such as sink marks in the whole molded product 3-2) Releasability Releasability is obtained by molding 12 130 mm square, 2 mm thick sheets. ◎: All molded articles fell naturally with the protruding pins of the injection molding machine. ：: 10 or more sheets fell naturally. ：: 1 to 9 sheets fell naturally. ×: All did not fall naturally. 4) Hardness JIS K According to 7215, a 6.3 mm thick pressed sheet was used as a test piece.

[0051]

[Table 1]

[0052]

[Table 2]

(Examples 1 and 2) Resin compositions were prepared in the amounts shown in Table 1 in accordance with the above-mentioned steps. Table 1 shows the results
Shown in The resin composition of the present invention has excellent rebound resilience, wear resistance, and moldability.

(Comparative Example 1) The results are shown in Table 1. Only the component (i) is inferior in moldability, particularly mold release property, to the examples (1 and 2) of the present invention.

Reference Example 1 The results are shown in Table 1. In order to obtain a sufficient rebound resilience and abrasion resistance, it is desirable that the amount of the component (i) according to the present invention is 100 parts by weight or more based on 100 parts by weight of the component (a).

(Example 3) A resin composition was prepared according to the above-mentioned steps using the respective components in the amounts shown in Table 2. In the third embodiment,
The component (i) was changed from the polyurethane resin having a hardness of HDA80 of Examples 1 and 2 to a hardness of 90. Table 2 shows the results.
The resin composition of the present invention has excellent rebound resilience, wear resistance, and moldability.

Example 4 A resin composition was prepared in the amounts shown in Table 2 in accordance with the above steps. Table 2 shows the results. The resin composition of the present invention has excellent rebound resilience, wear resistance, and moldability. In particular, the addition of the components (f) and (g) significantly improves the abrasion resistance due to the improved compatibility.

(Comparative Examples 3 and 4) The results are shown in Table 2. In Comparative Examples 3 and 4, Table 2 shows the results obtained using Tuftec H1051 and M1913 as the component (a). Examples 3 and 4
On the other hand, moldability is particularly poor.

[0059]

As described above, according to the present invention, a golf ball cover material having improved injection moldability while maintaining the excellent wear resistance and rebound resilience of a conventional golf ball cover material. A thermoplastic resin composition can be obtained.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) C08L 9/00 C08L 9/00 9/06 9/06 15/00 15/00 23/00 23/00 53 / 02 53/02 91/00 91/00 101/00 101/00 F-term (reference) 4J002 AC035 AC081 AC111 AE052 BB033 BB053 BB063 BB073 BB144 BB153 BB154 BB175 BP011 CF035 CK025 CL005 EK036 EK046 EK056 EK086 FD070 PAJ01 146 PA64 PA88 PA95 PB30 PC02 4J026 AA11 AA12 AA13 AA14 AB02 AB07 AB28 AC10 AC11 AC16 AC18 AC19 AC23 AC32 BA25 BA27 BA30 BA33 BA34 BA35

Claims (4)

[Claims] 1) 100 parts by weight of at least one selected from the group consisting of (a) an aromatic vinyl compound-conjugated diene compound copolymer and / or a hydrogenated product thereof, and (b) a non-aromatic rubber softener 0 To 240 parts by weight, (c) peroxide-crosslinked olefin-based resin, and / or copolymer thereof 0 to 10
0 parts by weight, (d) 0-100 parts by weight of a peroxide-decomposable olefin-based resin and / or a copolymer thereof, (e)
0 to 30 parts by weight of liquid polybutadiene, (f) 0 to 15 parts by weight of an unsaturated glycidyl compound or a derivative thereof, (g) 0 to 15 parts by weight of an unsaturated carboxylic acid or a derivative thereof, (h)
(Meth) acrylate compound having a hydroxyl group 0
~ 15 parts by weight, and (j) an organic peroxide (a) ~
(H) 0 to 3.5 parts by weight based on 100 parts by weight in total;
Further, (i) a polyester polymer or a copolymer thereof,
Polyurethane polymer, or its copolymer, polyamide polymer, or its copolymer, polymethylpentene polymer,
Or a thermoplastic resin composition for a golf ball cover material, comprising 0 to 1500 parts by weight of at least one compound selected from the group consisting of copolymers thereof. 2. Component (a) comprises: (a-1) an aromatic vinyl compound content of 50% by weight or less, and a number average molecular weight (Mn) of 5,000 to 1,50.
A block copolymer having a polydispersity (Mw / Mn) of 10 or less, or a hydrogenated product thereof, and (a-2) an aromatic vinyl compound content of 50% by weight or less, Number average molecular weight (Mn) of 5,000 to 1,000
And at least one selected from the group consisting of a random copolymer having a polydispersity (Mw / Mn) of 10 or less and a hydrogenated product thereof. The thermoplastic resin composition for a golf ball cover material according to the above. 3. Component (a-1) is a hydrogenated styrene-isoprene-butadiene-styrene block copolymer and / or a hydrogenated styrene-isoprene-styrene block copolymer, wherein at least one of the olefinically unsaturated bonds is present. 70%
3. The thermoplastic resin composition for a golf ball cover material according to claim 2, wherein is hydrogenated. 4. The golf ball according to claim 2, wherein the component (a-2) is a hydrogenated styrene-butadiene random copolymer and at least 70% of its olefinically unsaturated bonds are hydrogenated. Thermoplastic resin composition for cover material.