JPH09290035A - Golf club head - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a lightweight golf club head having excellent rigidity by molding the golf club head with a liquid crystal resin compound blended with a specific quantity of a filler to a liquid crystal resin. SOLUTION: A liquid crystal resin composition blended with a filler of 0-200 pts.wt. to a liquid crystal resin of 100 pts.wt. to manufacture this golf club head 1, particularly the outer shell section of the head 1. This liquid crystal resin is a resin capable of forming the anisotropic fused phase when fused, polyester and/or polyester amide is preferably used, and practically a resin selected from a group of liquid crystal polyester of all aromatics, liquid crystal polyester amide of all aromatics, liquid crystal polyester having the ethylene dioxy unit, and liquid crystal polyester amide having the ethylene dioxy unit is used. The blended quantity of the filler is set to 10-100 pts.wt., and the fiber- like filler having the aspect ratio of 3 or above is preferably used.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a golf club head having high rigidity while being lightweight.

[0002]

2. Description of the Related Art Golf clubs include so-called wood clubs such as drivers, spoons, buffies and creeks.
There are so-called iron clubs and putters such as irons, pitching wedges, sand wedges, etc. of each count,
The material of the club head was literally wood for wood clubs and metal for iron clubs.

However, with the widespread use and generalization of golf in recent years, the distinction between the materials of wood and iron has disappeared. In particular, persimmon (persimmon material) has been used for club heads of wood clubs for a long time due to its good hitting sound and good appearance. However, as persimmon material with excellent characteristics has become difficult to obtain in recent years, it has become a substitute material for persimmon. Metallic materials such as stainless steel, aluminum, and titanium, and fiber-reinforced resin materials aimed at further weight reduction have been used. Among them, the club head made of a fiber-reinforced resin material can be made lighter than the club head made of a metal material, and therefore, it has been put to practical use especially for beginners and women.

[0004]

However, although a golf head made of a fiber-reinforced resin material can be made lighter in weight than a club head made of a metal material, it is one step inferior in terms of rigidity, so that improvement was required. . In order to increase the rigidity of the fiber reinforced resin material, it is necessary to increase the content of the reinforcing fiber. However, due to the fact that carbon fiber, glass fiber, or other fiber having a relatively large elastic modulus is used as the reinforcing fiber, as the content of the reinforcing fiber is increased, the reinforcing fiber is more likely to break during kneading with the resin. There is a problem that sufficient rigidity cannot be obtained. In order to compensate for the decrease in rigidity due to the breakage of the reinforcing fibers, it is necessary to increase the weight such as increasing the thickness of the face of the club head, and eventually there is a dilemma of reducing the weight. An object of the present invention is to provide a golf club head that is lightweight and has excellent rigidity.

[0005]

That is, the golf club head of the present invention is characterized by comprising a liquid crystal resin composition in which 0 to 200 parts by weight of a filler is mixed with 100 parts by weight of the liquid crystal resin. It is a thing. In particular, this liquid crystalline resin composition is used in the outer shell of a golf club head.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION In the present invention, the liquid crystalline resin used for molding a golf club head is a resin capable of forming an anisotropic molten phase when melted, and polyester and / or polyesteramide is preferable. More specifically, those selected from the group of wholly aromatic liquid crystalline polyesters, wholly aromatic liquid crystalline polyesteramides, liquid crystalline polyesters having ethylenedioxy units, and liquid crystalline polyesteramides having ethylenedioxy units. Is preferred.

Preferred examples of the liquid crystalline polyester used in the present invention are the following (I), (III) and (IV)
A liquid crystalline polyester composed of structural units of (I), (I
A liquid crystalline polyester comprising the structural units I) and (IV) or a liquid crystalline polyester selected from the group of liquid crystalline polyesters comprising the structural units (I), (II), (III) and (IV). Can be mentioned.

[0008]

Embedded image (However, R ₁ in the formula is

[0009]

Embedded image It represents one or more groups selected from, R ₂ is

[0010]

[Chemical 6] And at least one group selected from In the formula, X represents a hydrogen atom or a chlorine atom, and the structural units (II) and (III)
And the structural unit (IV) are substantially equimolar. )

The above structural unit (I) is a structural unit of polyester produced from p-hydroxybenzoic acid, and
I) is 4,4'-dihydroxybiphenyl, 3,3 ',
5,5'-tetramethyl-4,4'-dihydroxybiphenyl, hydroxine, t-butylhydroquinone,
Phenylhydroquinone, methylhydroquinone, 2,
A structural unit formed from an aromatic dihydroxy compound selected from 6-dihydroxynaphthalene, 2,7-dihydroxynaphthalene, 2,2-bis (4-hydroxyphenyl) propane and 4,4′-dihydroxydiphenyl ether is replaced by a structural unit ( III) is a structural unit formed from ethylene glycol, structural unit (IV) is terephthalic acid, isophthalic acid, 4,4'-diphenyldicarboxylic acid, 2,6-naphthalenedicarboxylic acid, 4,4'-diphenyletherdicarboxylic acid, Structure formed from an aromatic dicarboxylic acid selected from 1,2-bis (phenoxy) ethane-4,4'-dicarboxylic acid and 1,2-bis (2-chlorophenoxy) ethane-4,4'-dicarboxylic acid Indicates a unit. Of these, R ₁ is

[0012]

Embedded image And R ₂ is

[0013]

Embedded image Is particularly preferred. Further, as the liquid crystalline polyesteramide, in addition to the above structural units (I) to (IV), p
Polyesteramides which form an anisotropic melt phase containing p-iminophenoxy units formed from aminophenols are preferred.

The liquid crystalline polyester which can be used in the present invention is a copolymer comprising the above structural units (I), (II) and (IV), or (I), (II), (III) and (IV). And the above structural units (I), (II), (III) and (IV)
Is arbitrary. However, the following copolymerization amount is preferred from the viewpoint of fluidity. That is, when the structural unit (III) is contained, the total of the structural units (I) and (II) is, from the viewpoint of heat resistance, flame retardancy and mechanical properties,
The total amount of (I), (II) and (III)] is preferably 60 to 95 mol%, more preferably 75 to 93 mol%. The structural unit (III) is preferably 40 to 5 mol% of the total of (I), (II) and (III), more preferably 25 to 7 mol%. The molar ratio [(I) / (II)] of the structural units (I) and (II) is preferably 75/25 to 95/5, and more preferably from the viewpoint of the balance between heat resistance and fluidity. Is 78/22 to 93/7. Further, the structural unit (IV) is substantially equimolar to the total of the structural units (II) and (III).

On the other hand, when the structural unit (III) is not contained, the structural unit (I) is composed of (I) and (I) from the viewpoint of fluidity.
It is preferably 40 to 90 mol% of the total of I),
It is particularly preferably 60 to 88 mol%, and the structural unit (IV) is substantially equimolar to the structural unit (II). In the polycondensation of the liquid crystalline polyester which can be preferably used in the present invention, in addition to the components constituting the structural units (I) to (IV), 3,3′-diphenyldicarboxylic acid and 2,2 ′ are added. -Aromatic dicarboxylic acid such as diphenyldicarboxylic acid, adipic acid, azelaic acid, sebacic acid,
Aliphatic dicarboxylic acids such as dodecanedioic acid, alicyclic dicarboxylic acids such as hexahydroterephthalic acid, chlorohydroquinone, 4,4'-dihydroxydiphenyl sulfone, 4,4'-dihydroxydiphenyl sulfide,
Aromatic diols such as 4,4′-dihydroxybenzophenone, 1,4-butanediol, 1,6-hexanediol, neopentyl glycol, 1,4-cyclohexanediol, and aliphatic such as 1,4-cyclohexanedimethanol, Alicyclic diols and aromatic hydroxycarboxylic acids such as m-hydroxybenzoic acid and 2,6-hydroxynaphthoic acid and p-aminophenol and p-aminobenzoic acid can be further copolymerized in a small proportion. .

For example, in the production of the above-mentioned preferably used liquid crystalline polyester, when the structural unit (III) is not contained, the following (1) and (2), structural unit (III)
When it contains, the production method of (3) is preferred. (1) Deacetic acid polycondensation reaction of p-acetoxybenzoic acid and a diacylated aromatic dihydroxy compound such as 4,4′-diacetoxybiphenyl and 4,4′-diacetoxybenzene with an aromatic dicarboxylic acid such as terephthalic acid. How to manufacture by.

(2) p-hydroxybenzoic acid and 4,
A method in which an aromatic dihydroxy compound such as 4'-hydroxybiphenylhydroquinone and an aromatic dicarboxylic acid such as terephthalic acid are reacted with acetic anhydride to acylate a phenolic hydroxyl group, and then a deacetic acid polycondensation reaction is carried out. (3) by the method of (1) or (2) in the presence of a polyester polymer such as polyethylene terephthalate, an oligomer, or a bis (β-hydroxyethyl) ester of an aromatic dicarboxylic acid such as bis (β-hydroxyethyl) terephthalate. Method of manufacturing.

Although these polycondensation reactions proceed without a catalyst, when it is preferable to add a metal compound such as stannous acetate, tetrabutyl titanate, potassium acetate and sodium acetate, antimony trioxide, or magnesium metal. is there. Some of the liquid crystalline resins of the present invention are capable of measuring logarithmic viscosity in pentafluorophenol, and in that case, a value measured at 60 ° C. at a concentration of 0.1 g / dl is 0.3 dl / g. The above is preferable, and when the structural unit (III) is included, 0.5 to 3.0 dl / g is preferable,
2.0 to 15.0 when the structural unit (III) is not included
dl / g is preferred.

The melt viscosity of the liquid crystalline resin in the present invention is preferably 1 to 2,000 Pa · s, and particularly 2 to
1,000 Pa · s is more preferable. Here, the melt viscosity is a value measured by a high-pressure capillary viscometer using a capillary having a diameter of 1 mm and a length (l) ≧ 5 mm under the condition of melting point + 10 ° C. and shear rate of 1000 / sec. Also,
The melting point means that the resin is from room temperature to 20 in the differential calorimetry.
After observing the endothermic peak temperature (Tm1) observed when measured under a temperature rising condition of ° C / min, after holding at a temperature of Tm1 + 20 ° C for 5 minutes, and then once cooling to room temperature under a temperature lowering condition of 20 ° C / min The endothermic peak temperature (Tm2) observed when the measurement is performed again under the temperature rising condition of 20 ° C./min.

The amount of the filler that can be added to the liquid crystalline resin of the present invention is 0 to 20 relative to 100 parts by weight of the liquid crystalline resin.
It is 0 parts by weight, preferably 10 to 100 parts by weight. The filler is not particularly limited, for example, glass fiber, carbon fiber, aramid fiber, potassium titanate fiber, gypsum fiber, aluminum borate fiber, brass fiber, stainless fiber, steel fiber, ceramic fiber, boron whisker fiber, asbestos Fiber, graphite, silica, talc, clay, mica, glass beads, glass flakes, glass microballoons, bentonite, calcium carbonate, calcium oxide, titanium oxide, aluminum oxide, calcium sulfate, barium sulfate, molybdenum disulfide, zinc oxide, oxidation Examples thereof include fibrous, powdery, granular or plate-like inorganic fillers such as magnesium and hydrotalcite.

Of these, fibrous fillers are preferable, and
An aspect ratio (fiber length / fiber diameter) of 3 or more, preferably 5 or more is preferable. In the present invention, carbon black can be further added, and the carbon black that can be used is not particularly limited, but the pH is 3 to 1 from the viewpoint of mechanical properties of the obtained composition.
No. 1 is preferable, and one having a pH of 4 to 9 is particularly preferable.

The compounding amount of carbon black is the liquid crystal resin 1
0.01 to 10 parts by weight is preferable with respect to 00 parts by weight,
It is more preferably 0.1 to 5 parts by weight. The liquid crystalline resin of the present invention may further contain an olefin polymer. Examples of olefin polymers include polyethylene, polypropylene, ethylene and α having 3 or more carbon atoms.
-One selected from a copolymer consisting of olefin, a copolymer consisting of propylene and α-olefin having 4 or more carbon atoms, a copolymer consisting of ethylene and α-olefin having 3 or more carbon atoms and non-conjugated diene That is all.

The α-olefin having 3 or more carbon atoms is preferably propylene, butene-1, pentene-.
1,3-methylpentene-1, octacene-1 and the like, more preferably propylene and butene-1, and these can be used in combination of two or more kinds. Examples of the α-olefin having 4 or more carbon atoms include those excluding propylene from the above α-olefins having 3 or more carbon atoms, and these can be used in combination of two or more kinds.

The non-conjugated diene is preferably 5-ethylidene-2-norbornene, dicyclopentadiene,
1,4-hexadiene and the like can be used. The copolymerization ratio of ethylene and the α-olefin having 3 or more carbon atoms in the copolymer of ethylene and the α-olefin having 3 or more carbon atoms is usually 40/60 to 99/1 (molar ratio), preferably 70/30 to 95/5 (molar ratio).

The copolymerization amount of ethylene in the copolymer consisting of ethylene, an α-olefin having 3 or more carbon atoms and a non-conjugated diene is usually 5 to 96.9 mol%, preferably 30 to 84.5 mol%. And α- having 3 or more carbon atoms
The copolymerization amount of the olefin is usually 3 to 80 mol%, preferably 15 to 60 mol%, and the copolymerization amount of the non-conjugated diene is usually 0.1 to 15 mol%, preferably 0.5 to 50 mol%.
10 mol%.

Further, propylene and α- having 4 or more carbon atoms
The copolymerization amount of propylene in the copolymer composed of olefin and non-conjugated diene is usually 5 to 96.9 mol%,
It is preferably from 30 to 84.5 mol% and has 3 carbon atoms.
The copolymerization amount of the above α-olefin is usually 3 to 80 mol%, preferably 15 to 60 mol%, and the copolymerization amount of the non-conjugated diene is usually 0.1 to 15 mol%, preferably It is 0.5 to 10 mol%.

Specific examples of these copolymers include ethylene / propylene copolymers, ethylene / butene-1 copolymers, ethylene / pentene-1 copolymers, ethylene / propylene / butene-1 copolymers, Propylene / pentene-1 copolymer, propylene / butene-1 copolymer, ethylene / propylene / 5-ethylidene-2-norbornene copolymer, ethylene / propylene / 1,4-hexadiene copolymer, propylene / butene- Examples include 1 / 1,4-hexadiene copolymer and ethylene / propylene / dicyclopentadiene copolymer. Among them, ethylene / propylene copolymers and ethylene / butene-1 copolymers are more preferable because they have excellent heat resistance.

Two or more of the above olefin polymers may be used in combination. The weight average molecular weight of the olefin polymer is 10,000 to 600,000, preferably 300.
00-500000, more preferably 100000-
It is preferably in the range of 450,000. Here, the weight average molecular weight can be measured by a gel permeation chromatograph (GPC) method. O- as a typical solvent
Using dichlorobenzene, the molecular weight can be measured based on monodisperse polystyrene of known molecular weight.

The amount of the above olefin polymer added is preferably 0.01 to 10 parts by weight, particularly preferably 0.1 to 5 parts by weight, based on 100 parts by weight of the liquid crystal resin. In the resin composition of the present invention, a thermoplastic resin (for example, polyethylene terephthalate, polybutylene terephthalate, polycyclohexane dimethylene terephthalate, polyethylene naphthalate, poly Polyester resin typified by butylene naphthalate and polyarylate, polyacetal resin, polystyrene resin, polyvinyl chloride resin, nylon 6, nylon 6.6, nylon 6/10, nylon 6 ・
Polyamide resin such as 12, nylon 11, nylon 12, poly (meta-xylene adipamide), poly (hexamethylene terephthalamide), polycarbonate resin, ABS resin, polyphenylene oxide resin, polyphenylene sulfide resin, polyetherimide resin ,
Polyetheretherketone resin, polyetherketone resin, polyethersulfone resin, polysulfone resin, fluororesin, polyester polyether elastomer, polyester elastomer, etc.), antioxidants, heat stability Ordinary additives such as agents, ultraviolet absorbers, lubricants, colorants (except carbon black) including dyes and pigments, crystal nucleating agents, plasticizers, flame retardant aids, antistatic agents and the like can be added.

FIG. 1 shows an outline of a wood type golf club head integrally molded from the liquid crystalline resin composition of the present invention, and FIG. 2 shows a cross section of the golf club head taken along a plane orthogonal to the face. . The illustrated golf club head 1 is integrally molded from a liquid crystal resin composition and has a sole metal 4 attached to the bottom surface. This golf club head 1 comprises a hollow molded product whose outer shell is molded from a liquid crystalline resin composition, has a groove 3 formed in a face 2 of a ball striking face, and a hosel 5 formed at an end of a shaft. It seems that 6 is connected.

The present invention can be applied not only to the wood type golf club head shown in the drawing but also to an iron club or a putter golf club head. In the case of an iron club head, it is preferable to use a solid molded product instead of a hollow molded product. The golf club head of the present invention is preferably integrally molded by injection molding. As a preferable injection molding method, for example, a resin for an in-line type injection molding machine is set in the range of the melting point of the liquid crystalline resin to the melting point + 50 ° C. It is recommended to supply the composition and set the mold temperature of the in-line type injection molding machine in the range of about 70 ° C. to 150 ° C. for injection molding.

[0032]

EXAMPLES The present invention will be specifically described below with reference to examples. First, for use in the following examples, liquid crystalline polyesters A-1 to A-3 were produced by the following formulations. Reference Example 1 p-Hydroxybenzoic acid 995 parts by weight, 4,4'-dihydroxybiphenyl 126 parts by weight, terephthalic acid 118
Parts by weight, 216 parts by weight of polyethylene terephthalate having an intrinsic viscosity of about 0.6 dl / g and 960 parts by weight of acetic anhydride are charged into a reaction vessel equipped with a stirring blade and a distilling tube, and the mixture is kept under a nitrogen gas atmosphere at 100 to 250 ° C. for 5 hours. After reacting at 250 to 310 ° C. for 1.5 hours, the pressure was reduced to Torr at 315 ° C. for 90 minutes and then the reaction was continued for 1 hour to complete polycondensation. A liquid crystalline polyester resin (A-1) having the theoretical structural formula of was obtained.

This resin has a melting point of 314 ° C. and a melt viscosity of 3
It was 33 Pa · s at 24 ° C. and a shear rate of 1000 (1 / sec).

[0034]

Embedded image k / l / m / n = 80 / 7.5 / 12.5 / 20

Reference Example 2 Using the same apparatus as in Reference Example 1, deacetic acid polymerization was carried out under the following conditions. 28.8 kg of p-acetoxybenzoic acid and polyethylene terephthalate 7.6 with an intrinsic viscosity of about 0.6 dl / g
9 kg was charged, and the mixture was stirred at 240 ° C. for 3 hours in a nitrogen gas atmosphere. Then, the temperature inside the can is increased to 240 to 3 over 2 hours.
The temperature was brought to 00 ° C., and the polymerization vessel was depressurized to 1 Torr over 90 minutes. After that, stirring was continued for 1 hour to complete the polycondensation. As a result, a theoretical amount of acetic acid was distilled off, and a liquid crystalline polyester resin (A-2) having the following theoretical structural formula was obtained. The melting point of this resin is 284 ° C, the melt viscosity is 294 ° C, and the shear rate is 1
It was 50 Pa · s at 000 (1 / second).

[0036]

Embedded image k / l / m = 80/20/20 Reference Example 3 Using the same apparatus as in Reference Example 1, deacetic acid polymerization was carried out under the following conditions. 20.1 kg p-hydroxybenzoic acid, 10.16 kg 2-hydroxy-naphthoic acid and 22.44 acetic anhydride.
Was charged and reacted in a nitrogen gas atmosphere at 100 to 250 ° C. for 5 hours and at 240 to 310 ° C. for 1.5 hours, and then 31
The pressure was reduced to 1 Torr in 1 hour at 0 ° C. Then 1.25
When the reaction was carried out for a period of time to complete the polycondensation, almost the theoretical amount of acetic acid was distilled off, and a liquid crystalline polyester resin (A-3) having the following theoretical structural formula was obtained. The melting point of this resin is 28
3 ° C, melt viscosity 293 ° C, shear rate 1000 (1 /
It was 55 Pa · s in seconds).

[0037]

Embedded image k / l = 73/27 Examples 1 to 3, Comparative Examples 1 to 2 Using a 30 mmφ twin-screw extruder having an intermediate addition port, the liquid crystalline resin or ABS resin obtained in Reference Examples 1 to 3 (manufactured by Toray Industries, Inc.) "Toyolac type 100") is supplied to the raw material supply port of the twin-screw b extruder set to the cylinder temperature shown in Table 1, and then carbon fiber (6 μm system, 6 mm gut, epoxy convergent) is supplied from the intermediate addition port. Was supplied so that the carbon fiber content would be the same, and the mixture was melt-kneaded and pelletized. Next, the obtained pellets were injection-molded by an injection molding machine set to the cylinder temperature shown in Table 1 to manufacture the club head shown in FIG.
The obtained club head was cut into a piece of 10 mm width × 40 mm length × 10 mm thickness, and the flexural modulus was measured according to ASTM D790. Table 1 shows the results.

[0038]

[Table 1] As is clear from the results in Table 1, the golf club head of the present invention is superior in rigidity as compared with the comparative example.

[0039]

As described above, since the golf club head of the present invention is integrally molded from the liquid crystal resin composition, it can be made lightweight and have high rigidity, especially for beginners and women. It is effective for business.

[Brief description of drawings]

FIG. 1 is a schematic front view of a golf club head of the present invention.

FIG. 2 is a cross-sectional view of the golf club head of the present invention.

[Explanation of symbols]

 1 head 2 face 4 sole metal 5 hosel

Claims (7)

[Claims] 1. A golf club head molded from a liquid crystal resin composition in which 0 to 200 parts by weight of a filler is mixed with 100 parts by weight of the liquid crystal resin. 2. The golf club head according to claim 1, wherein the liquid crystalline resin composition is used in the outer shell of the golf club head. 3. The liquid crystalline resin comprises a wholly aromatic liquid crystalline polyester, a wholly aromatic liquid crystalline polyesteramide, a liquid crystalline polyester having an ethylenedioxy unit, and a liquid crystalline polyesteramide having an ethylenedioxy unit. The golf club head according to claim 1, which is a resin selected from the group. 4. The liquid crystalline resin comprises the following (I) and (III)
And a liquid crystalline polyester comprising the structural units of (IV),
Selected from the group of liquid crystalline polyesters composed of structural units (I), (II) and (IV), and liquid crystalline polyesters composed of structural units (I), (II), (III) and (IV) The golf club head according to claim 1, which is a resin. Embedded image (However, R ₁ in the formula is And R ₂ represents one or more groups selected from And at least one group selected from In the formula, X represents a hydrogen atom or a chlorine atom, and the structural units (II) and (III)
And the structural unit (IV) are substantially equimolar. ) 5. The liquid crystalline resin is a structural unit (I),
(II), (III) and (IV), the structural unit (I)
And the total of (II) is 60 to 95 mol% with respect to the total of (I), (II) and (III), and the structural unit (III) is (I), (I
It is 40 to 5 mol% with respect to the total of I) and (III), and the molar ratio [(I) / (II)] of structural units (I) and (II) is 75/25 to 95/5. The golf club head according to claim 4. 6. The golf club head according to claim 1, wherein the compounding amount of the filler is 10 to 100 parts by weight. 7. The golf club head according to claim 1, wherein the filler is a fibrous filler having an aspect ratio of 3 or more.