JP5167111B2 - Grip for golf club and manufacturing method thereof - Google Patents

Description

  The present invention relates to a golf club grip, and more particularly, a golf club grip made of a thermoplastic elastomer capable of strengthening the bonding between a cylindrical main body portion and a grip end portion and preventing air accumulation in the bonding portion, and the same It relates to a manufacturing method.

  Rubber grips made of natural rubber, synthetic rubber, etc. are known as golf club grips, but recently, grips made of various thermoplastic elastomers such as thermoplastic elastomers with excellent surface design have been proposed. (For example, refer to Patent Document 1).

  The grip sometimes has a grip end portion that is harder than the cylindrical main body portion in order to improve stability when gripping strongly. When manufacturing such a grip, for example, first, a grip end part is injection-molded using a thermoplastic elastomer composition. Next, the grip end portion is disposed inside the mold, and a thermoplastic elastomer composition having a lower hardness is injected into the mold to join the two while forming the cylindrical main body portion.

As described above, the cylindrical main body and the grip end are joined by the heat at the time of injection molding, so that they are greatly affected by the properties of the injection material, injection molding conditions, and the like. Therefore, there are cases where sufficient bonding strength cannot be obtained. In addition, there is a problem that air is accumulated in the joint portion between the two, resulting in poor appearance, and the joint strength is reduced due to the air accumulation.
JP 2004-154228 A

  An object of the present invention is to provide a golf club grip made of a thermoplastic elastomer and a method for manufacturing the same that can further strengthen the bonding between the cylindrical main body portion and the grip end portion and prevent air from being accumulated in the bonding portion. is there.

  In order to achieve the above object, a golf club grip according to the present invention comprises a grip end portion formed of a thermoplastic elastomer composition having an end surface on one end side in the cylinder axis direction of a cylindrical portion, and the grip end portion at one end. A golf club grip comprising a cylindrical main body formed of a thermoplastic elastomer composition having a hardness lower than that of the thermoplastic elastomer composition that has been heat-bonded. While having a groove portion extending from one end to the other end, and having a through hole in the end face of the grip end portion, the thermoplastic elastomer composition forming the cylindrical main body portion covers the outer peripheral wall of the grip end portion, and It is characterized in that at least a part of the groove formed inside the peripheral wall is filled.

  In the golf club grip manufacturing method of the present invention, a grip end portion having an end face on one end side in the cylinder axis direction of a cylindrical portion is previously molded from a thermoplastic elastomer composition, and the grip end portion is placed in a mold. And then injecting a thermoplastic elastomer composition having a hardness lower than that of the thermoplastic elastomer composition into the mold to form a cylindrical main body portion, and at one end of the cylindrical main body portion, A golf club grip manufacturing method in which a grip end portion is thermally bonded, wherein a groove portion extending from one end to the other end in a cylindrical axis direction is formed inside a peripheral wall of the grip end portion, and a through hole is formed in an end surface of the grip end portion And the injected thermoplastic elastomer composition covers the outside of the peripheral wall of the grip end portion and reduces the number of grooves formed inside the peripheral wall. Also characterized in that so as to fill a part.

  According to the present invention, the thermoplastic elastomer composition having a groove extending from one end to the other end in the cylinder axis direction on the inner side of the peripheral wall of the grip end part and forming the cylindrical main body part is provided outside the peripheral wall of the grip end part. Covering and filling at least part of the groove formed inside the peripheral wall increases the area of the joint between the grip end and the cylindrical body, making it possible to strengthen the joint between the two become. Further, when the thermoplastic elastomer composition forming the cylindrical main body portion is injected, the air moves along the groove portion inside the peripheral wall of the grip end portion, and the outside of the mold is passed through the through hole on the end surface of the grip end portion. Therefore, it is possible to prevent the accumulation of air at the joint.

  The grip for golf clubs and the manufacturing method thereof according to the present invention will be described based on the embodiments shown in the drawings.

  As illustrated in FIGS. 1 to 3, a golf club grip 1 (hereinafter referred to as a grip 1) according to the present invention includes a cylindrical main body portion 2 and a grip end portion 3. The cylindrical main body 2 has a cylindrical shape having a taper in the cylinder axis direction, and the grip end 3 is joined to one end (large diameter side) in the cylinder axis direction. The cylindrical main body 2 and the grip end 3 are respectively formed of thermoplastic elastomer compositions e1 and e2, and the grip end 3 is higher in hardness than the cylindrical main body 2.

  As illustrated in FIGS. 4 to 6, the grip end portion 3 has an end surface 3 b on one end side in the cylinder axis direction of the cylindrical portion 3 a. The cylindrical portion 3a has a shape formed by being tapered in the cylinder axis direction, and has a shape in which one end side (large diameter side) in the cylinder axis direction is closed by the end surface 3b, but penetrates the end surface 3b. A hole 6 is formed so that the inside and outside of the grip end portion 3 communicate with each other. The through hole 6 is formed by connecting a small diameter hole and a large diameter hole.

  Further, the grip end portion 3 has a groove portion 5 extending from one end to the other end in the cylinder axis direction inside the peripheral wall of the cylindrical portion 3a. The groove portion 5 is formed in a straight line shape in the cylinder axis direction, and a plurality of the groove portions 5 are provided at intervals in the cross section of the grip end portion 3. Thus, a protrusion 4 is formed between the groove 5 and the groove 5. In this embodiment, twelve groove portions 5 having the same specification are provided in the cross section of the cylindrical portion 3a with an equal central angle.

  It is preferable to provide a plurality of groove portions 5 at an equal central angle, and the size and number of the groove portions 5 are appropriately determined. Further, from the viewpoint of air bleeding described later, the groove portion 5 is preferably the minimum length from one end to the other end in the cylindrical axis direction of the cylindrical portion 3a as illustrated in FIG. It can also be formed in parallel straight lines, or can be formed in a spiral shape.

  As illustrated in FIGS. 2 and 3, the thermoplastic elastomer composition e <b> 1 forming the cylindrical main body portion 2 covers the outer peripheral wall of the cylindrical portion 3 a of the grip end portion 3, and is formed in the groove portion 5 formed on the inner peripheral wall. It is in a filled state. Note that the top surface of the protrusion 4 is not covered with the thermoplastic elastomer composition e1 and is exposed.

  Thus, in this invention, the groove part 5 is formed in the peripheral wall inner side of the grip end part 3, and the thermoplastic elastomer composition e1 which forms the cylindrical main body part 2 covers the outer peripheral wall outside of the grip end part 3, and the groove part 5 Since at least a part of this is filled, the area of the joint portion between the grip end portion 3 and the cylindrical main body portion 2 increases. Therefore, regardless of the properties of the injection material (thermoplastic elastomer compositions e1 and e2), injection molding conditions, and the like, it is possible to further strengthen the bonding between the two.

  In this embodiment, the portion from the other end of the groove 5 to a position in the middle of the cylinder axis direction is filled with the thermoplastic elastomer composition e1 that forms the cylindrical main body 2. When the thermoplastic elastomer composition e1 is filled over the entire length of the groove portion 5, the bonding area can be maximized. However, in the present invention, at least a part of the groove portion 5 only needs to be filled.

  The thermoplastic elastomer composition e1 that forms the cylindrical main body 2 and the thermoplastic elastomer composition e2 that forms the grip end 3 include a side containing a hydrogen-bonded cross-linking site having a carbon-containing group and a nitrogen-containing heterocyclic ring. Compositions comprising thermoplastic elastomers having other side chains containing covalently crosslinked sites having chain and carbon-containing groups and nitrogen-containing heterocycles, or hydrogen-bonded bridges having carbon-containing groups and nitrogen-containing heterocycles Any of the compositions comprising a thermoplastic elastomer having a side chain containing a moiety or a side chain containing a covalently crosslinked moiety having a carbon-containing group and a nitrogen-containing heterocycle can be exemplified.

  More specifically, as the thermoplastic elastomer composition e1 forming the cylindrical main body 2, for example, a maleated olefin elastomer and a nitrogen-containing heterocyclic polyfunctional alcohol as a crosslinking agent, a soft polyolefin resin or a styrene resin A thermoplastic elastomer composition containing thermoplastic elastomer and paraffin oil as essential components can be used. The hardness of the cylindrical main body 2 is, for example, 40 to 80 (JIS-A), the 100% modulus is 0.5 MPa to 4.0 MPa, and the compression set is 60% or less.

  On the other hand, as the thermoplastic elastomer composition e2 forming the grip end portion 3, for example, a hard polyolefin resin, a styrenic thermoplastic elastomer, and paraffin using a maleated olefin elastomer and a nitrogen-containing heterocyclic polyfunctional alcohol as a crosslinking agent. A thermoplastic elastomer composition containing oil as an essential component can be used. The hardness of the grip end portion 3 is, for example, 50 to 90 (JIS-A), and the 100% modulus is 3.0 MPa to 6.0 MPa.

  The hardness and 100% modulus of the cylindrical main body portion 2 and the grip end portion 3 are set so that the grip end portion 3 is larger within the range described above.

  Since the cylindrical main body 2 and the grip end portion 3 are formed by the thermoplastic elastomer compositions e1 and e2 containing the above-described components, the vulcanized rubber is more flexible than the thermoplastic elastomer in terms of flexibility and wear resistance. Good physical properties close to can be obtained. The thermoplastic elastomer compositions e1 and e2 blended with the above components can be injection-molded. Even after being molded once, the thermoplastic elastomer compositions e1 and e2 have a certain degree to the virgin thermoplastic elastomer compositions e1 and e2. Up to the ratio (for example, about 50% by weight), the mixture can be pulverized and mixed to be reinjected and recycled.

  When the hardness (JIS-A) of the cylindrical main body 2 is less than 40, the 100% modulus decreases accordingly, and it becomes difficult to ensure 0.5 MPa or more. For this reason, the grip feels soft when gripped, but when actually swinging and hitting, the player feels as if the grip 1 moves in the hand because the grip is stronger and the sense of stability is lost. Such a sense hinders a stable swing.

  On the other hand, if the hardness (JIS-A) of the cylindrical main body 2 is more than 80, the 100% modulus is likely to exceed 4.0 MPa, the soft feeling is impaired, and the impact at the time of hitting the ball is increased. Will be uncomfortable. Accordingly, by setting the hardness (JIS-A) of the cylindrical main body 2 to 40 to 80 and the 100% modulus to 0.5 MPa or more and 4.0 MPa, an excellent feel that achieves both good fit and stability is obtained. be able to.

  In addition, by setting the compression set of the cylindrical main body 2 to 60% or less, it is possible to maintain the initial grip characteristics (fitness and stability) over a long period of time.

  The hardness and 100% modulus of the grip end portion 3 are set to be larger than those of the cylindrical main body portion 2, and the hardness is 50 to 90 (JIS-A), and the 100% modulus is 3.0 MPa to 6.0 MPa. It has become.

  If the grip end portion 3 has a hardness (JIS-A) of less than 50, the 100% modulus is reduced accordingly, the sense of stability at the time of swinging is impaired, the grip is difficult to grip, and a sense of incongruity is felt. On the other hand, if the grip end portion 3 has a hardness of more than 90, the 100% modulus becomes too large and the soft feeling is impaired.

  The player grips the grip 1 more strongly when swinging the golf club. However, the grip end portion 3 of the grip 1 is relatively hard so that the finger greatly affects the stability of the swing and the directionality of the hit ball. Deformation of the tip end region of the grip 1 that comes into contact with is suppressed. In other words, a right-handed player is less likely to loosen the middle finger, ring finger, and little finger of the left hand, and can obtain a better sense of stability. The player feels particularly good for players with a large grip.

  The method according to the invention for producing this grip 1 is as follows.

  First, the grip end portion 3 is previously molded from the thermoplastic elastomer composition e2. For example, it is formed into a desired shape by injection molding.

  Next, as illustrated in FIG. 7, the grip end portion 3 is installed at a predetermined position in the mold 8. An air vent hole (vent) 8 a is formed at a position corresponding to the through hole 6 in the cavity 9 where the grip end portion 3 is installed.

  Next, a thermoplastic elastomer composition e 1 having a lower hardness than the thermoplastic elastomer e 2 forming the grip end portion 3 is injected into the mold 8. The injected thermoplastic elastomer composition e1 is filled into the cavity 9 inside the mold 8 through the gate portion 10. Thereby, while the cylindrical main-body part 2 is shape | molded with the thermoplastic elastomer composition e1, the cylindrical main-body part 2 and the grip end part 3 are joined by the heat | fever at the time of shaping | molding, and the grip 1 is completed.

  At this time, the thermoplastic elastomer composition e1 is filled from the other end side of the groove portion 5, and the air a is moved along the groove portion 5 and discharged to the outside of the mold 8 through the air vent hole 8a. Can be made. Therefore, it is possible to prevent air accumulation at the joint portion between the cylindrical main body portion 2 and the grip end portion 3. Along with this, it is possible to prevent a decrease in bonding strength due to poor appearance and air accumulation in the bonding portion.

  Rather than filling the entire length of the groove portion 5 with the thermoplastic elastomer composition e1, filling the portion from the other end side of the groove portion 5 to the middle of the cylinder axis direction can more effectively prevent air accumulation at the joint portion. it can.

  As illustrated in FIGS. 8 and 9, the shaft 7 is attached to the grip 1 manufactured in this way. Here, on the outer peripheral surface of the shaft 7 inserted in the grip 1, in the grip end portion 3, the protruding portion 4 (thermoplastic elastomer composition e2) and the thermoplastic elastomer composition e1 filled in the groove portion 5 and Is in close contact.

  Therefore, the shaft 7 can be firmly held by the relatively hard protrusion 4 (thermoplastic elastomer composition e1). Further, since the relatively soft thermoplastic elastomer composition e1 filled in the groove portion 5 absorbs deformation when the grip 1 is strongly gripped, even in such a case, the projection portion 4 is firmly attached to the shaft 7. Retention can be maintained.

  The maleated olefin elastomer used in the thermoplastic elastomer compositions e1 and e2 refers to an elastomeric polymer in which maleic anhydride has a chemically stable bond (covalent bond) at the atom forming the main chain. And obtained by reacting the elastomeric polymer with a compound capable of introducing maleic anhydride.

  In the present invention, the elastomeric polymer containing maleic anhydride in the side chain is prepared by subjecting maleic anhydride to the above-mentioned elastomeric polymer by the usual conditions such as stirring under heating. It may be produced by a method of graft polymerization, or a commercially available product may be used.

  Examples of commercially available products include maleic anhydride-modified isoprene rubbers such as LIR-403 (manufactured by Kuraray Co., Ltd.) and LIR-410A (Kuraray Co., Ltd.); modified isoprene rubbers such as LIR-410 (manufactured by Kuraray Co., Ltd.); Clinac 110 , 221 and 231 (manufactured by Policer), carboxy-modified nitrile rubber; CPIB (manufactured by Nisseki Chemical), carboxy-modified polybutene such as HRPIB (manufactured by Nisseki Chemical Co., Ltd.); Nucrel (manufactured by DuPont Mitsui Polychemical) , Maleic anhydride modified ethylene-propylene rubber such as Yucaron (Mitsubishi Chemical Co., Ltd.), Tuffmer M (for example, MA8510 (Mitsui Chemicals)), etc. Anhydrous maleic such as Tuffmer M (for example, MH7020 (Mitsui Chemicals)) Acid-modified ethylene-butene rubber; Adtex series (maleic anhydride-modified E A, maleic anhydride modified EMA (manufactured by Nippon Polyolefin Co., Ltd.), HPR series (maleic anhydride modified EEA, maleic anhydride modified EVA (manufactured by Mitsui & DuPont Polyolefin)), Bond Fast series (maleic anhydride modified EMA (Sumitomo) Chemical)), Dumiran series (maleic anhydride modified EVOH (manufactured by Takeda Pharmaceutical Company Limited)), Bondine (maleic anhydride modified EEA (manufactured by Atofina)), Tuftec (maleic anhydride modified SEBS, M1943 (Asahi Kasei Corporation) Manufactured)), Kraton (maleic anhydride modified SEBS, FG1901X (manufactured by Kraton Polymer)), tufprene (maleic anhydride modified SBS, 912 (produced by Asahi Kasei)), Septon (maleic anhydride modified SEPS (produced by Kuraray)) Lexpearl (maleic anhydride modified EE ET-182G, 224M, 234M (manufactured by Nippon Polyolefin Co., Ltd.)), maleic anhydride-modified polyethylene such as Aurorene (maleic anhydride-modified EEA, 200S, 250S (manufactured by Nippon Paper Chemical Co., Ltd.)); Admer (for example, QB550, LF128 (manufactured by Mitsui Chemicals)) and the like;

  As the styrene thermoplastic elastomer, a known styrene thermoplastic elastomer obtained as a block copolymer from an aromatic vinyl compound and a conjugated diene can be used. In the present invention, the styrenic thermoplastic elastomer has a block polymerized portion by an aromatic vinyl corresponding to a crosslinking point at the terminal and has a weight average molecular weight of 100,000 or more from the viewpoint of improving compression set. Is preferred.

  Specific examples of the aromatic vinyl compound include styrene, α-methyl styrene, 3-methyl styrene, 4-propyl styrene and the like, and these may be used alone or in combination of two or more. May be. Specific examples of the conjugated diene include butadiene, isoprene, and mixtures thereof.

  By containing such a styrenic thermoplastic elastomer, the thermoplastic elastomer composition obtained has a good compression set. This is because the styrenic thermoplastic elastomer is incompatible, has low fluidity and forms an independent phase, and since the styrenic thermoplastic elastomer has a high affinity with oil, the styrenic thermoplastic elastomer and This is presumably because the oil is taken into the crosslinked structure of the thermoplastic elastomer composition in a state where the styrene thermoplastic elastomer has absorbed the oil.

  In the present invention, the method for producing the styrene-based thermoplastic elastomer is not particularly limited. For example, it is obtained by polymerizing the polymer (block (A)) obtained by polymerizing the aromatic vinyl compound and the conjugated diene. The method obtained by copolymerization (block copolymerization) with the polymer (block (B)) obtained is suitably exemplified. Here, the number average molecular weight of the block (A) is preferably in the range of 3000 to 50000. When the molecular weight is within this range, the mechanical strength of the resulting styrene-based thermoplastic elastomer is good, and the compression set resistance when obtaining the composition of the present invention using this styrenic thermoplastic elastomer is good.

  Moreover, it is preferable that the number average molecular weights of the said block (B) are the range of 10,000-200000. When the molecular weight is within this range, the viscosity at the time of mixing and melting in obtaining the composition of the present invention using the resulting styrenic thermoplastic elastomer becomes good, and the viscosity at the time of mixing and melting of the resulting composition of the present invention is high. It becomes good.

Furthermore, the styrenic thermoplastic elastomer obtained as a block copolymer has one or more blocks (A) and one or more blocks (B), and the block form is A- (BA ) _N or (AB) _m . Among these, the form of A-B-A is preferable because the fluidity and mechanical properties are good, and the form of using AB and A-B-A together is also possible.

  In the present invention, the styrene-based thermoplastic elastomer preferably has a styrene content of 10 to 60% by mass, more preferably 30 to 50% by mass. When the styrene content is within this range, the viscosity at the time of mixing and melting when the composition of the present invention is obtained is improved, and the mechanical strength and compression set resistance of the resulting composition of the present invention are further improved.

  Examples of such styrenic thermoplastic elastomers include hydrogenated styrene / isoprene / butadiene block copolymers, specifically, for example, styrene-isoprene block copolymer hydrogenated products (SEPS: styrene ethylene propylene styrene block copolymer). Styrene ethylene ethylene propylene styrene block copolymer (SEEPS), styrene ethylene butylene styrene block copolymer (SEBS) and the like. In the present invention, as such a styrenic thermoplastic elastomer, commercially available products such as Septon 2006 (SEPS, manufactured by Kuraray Co., Ltd.), Septon 4055 (SEEPS, manufactured by Kuraray Co., Ltd.) can be used.

  The nitrogen-containing heterocyclic polyfunctional alcohol is not particularly limited as long as it is a compound having two or more hydroxyl groups and having a nitrogen-containing heterocyclic ring.

  The nitrogen-containing heterocycle is preferably a 5-membered ring or a 6-membered ring. Examples of such nitrogen-containing heterocycle include pyrrolidine, pyrrolidone, oxindole (2-oxindole), indoxyl (3-oxindole), dioxindole, isatin, indolyl, phthalimidine, β-isoindigo, monoporphyrin , Diporphyrin, triporphyrin, azaporphyrin, phthalocyanine, hemoglobin, uroporphyrin, chlorophyll, phyloerythrin, imidazole, pyrazole, triazole, tetrazole, benzimidazole, benzopyrazole, benzotriazole, imidazoline, imidazolone, imidazolidone, hydantoin, pyrazoline, Pyrazolone, pyrazolidone, indazole, pyridoindole, purine, cinnoline, pyrrole, pyrroline, indole, indole Phosphorus, oxylindole, carbazole, phenothiazine, indolenine, isoindole, oxazole, thiazole, isoxazole, isothiazole, oxadiazole, thiadiazole, oxatriazole, thiatriazole, phenanthroline, oxazine, benzoxazine, phthalazine, pteridine, pyrazine, Phenazine, tetrazine, benzoxazole, benzisoxazole, anthranyl, benzothiazole, benzofurazan, pyridine, quinoline, isoquinoline, acridine, phenanthridine, anthrazolin, naphthyridine, thiazine, pyridazine, pyrimidine, quinazoline, quinoxaline, triazine, histidine, triazolidine, Melamine, adenine, isocyanurate, guanine, thymine, Examples include cytosine, isocyanuric acid and derivatives thereof.

  In addition, the nitrogen-containing heterocycle may have, for example, the same substituent as described above, or may have a hydrogen atom added or eliminated. In particular, tris (2-hydroxyethyl) isocyanurate (Tanac, manufactured by Nissan Chemical Co., Ltd.) is preferably used.

  Examples of the flexible polyolefin resin used for the thermoplastic elastomer composition E1 include an ethylene propylene copolymer having a polypropylene block and an ethylene propylene block. More specifically, it is a block copolymer in which a block composed of a polypropylene component (polypropylene block) and a block composed of a propylene / ethylene random copolymer component (ethylene propylene block) are connected.

  By containing such a soft polyolefin resin, the resulting thermoplastic elastomer composition retains excellent flexibility, and is excellent in fluidity and mechanical strength at high temperatures. This is because mechanical strength such as heat resistance, modulus and breaking strength is improved by the presence of polypropylene block with high crystallinity and hardness, and flexibility and fluidity at high temperature are achieved by the presence of ethylene propylene block which is a random copolymer. Is considered to be favorable.

  In the present invention, the soft polyolefin-based resin preferably has the polypropylene block in a proportion of 1 to 50 mol%, and preferably has the polypropylene block in a proportion of 10 to 25 mol%. More preferred. When the proportion of the polypropylene block is within this range, the mechanical strength of the composition of the present invention containing a soft polyolefin resin becomes better.

  In the present invention, the polypropylene block is preferably stereoregular from the viewpoint that the mechanical strength of the composition of the present invention containing a soft polyolefin resin is better, and the mechanical strength is even better. From the viewpoint of becoming isotactic, it is preferable.

  Furthermore, in the present invention, in the ethylene propylene block, in addition to propylene and ethylene, other polybutene components may be contained in an amount of about 5% by weight or less as required.

  Conventionally, the soft material which consists of polyolefin resin is manufactured by mixing the amorphous ethylene propylene rubber (EPR) etc. which were manufactured using the vanadium catalyst in polypropylene.

  In contrast, the soft polyolefin resin used in the present invention is produced by simultaneously polymerizing an elastomer component of polypropylene and a propylene / ethylene random copolymer using a titanium compound or an organoaluminum compound in one polymerization tank. It is preferable to do this. Alternatively, it may be produced by transferring separately synthesized polypropylene to another synthesis tank, charging ethylene and propylene therein, and polymerizing in the presence of a catalyst or the like.

  Such a flexible polyolefin-based resin is preferably a so-called reactor type copolymer in which the ethylene content in the ethylene propylene block is increased, and is commercially available as a prime TPO soft type manufactured by Prime Polymer Co., Ltd. In particular, those commercially available under the trade name M142E are preferably used.

  An example of the rigid polyolefin resin used for the thermoplastic elastomer e2 is polypropylene.

  About the thermoplastic elastomer composition e1, the nitrogen-containing heterocyclic polyfunctional alcohol is 0.1 to 3.0 parts by weight, the soft polyolefin resin is 50 to 150 parts by weight with respect to 100 parts by weight of the maleated olefin elastomer. It is preferable that the amount of styrene-based thermoplastic elastomer is 20 to 150 parts by weight and the amount of paraffin oil is 50 to 300 parts by weight.

  When the blending amount of the nitrogen-containing heterocyclic polyfunctional alcohol is less than 0.1 parts by weight, the number of cross-linked parts is reduced, and mechanical properties such as tensile strength and compression set are adversely affected. The number of parts to be increased increases, and the mechanical characteristics are similarly adversely affected. If the blending amount of the soft polyolefin resin is less than 50 parts by weight, the viscosity becomes high and injection molding becomes difficult, and if it exceeds 150 parts by weight, the compression set after molding is adversely affected. Further, when the blending amount of the styrene thermoplastic elastomer is less than 20 parts by weight, oil bleeding tends to occur, and when it exceeds 150 parts by weight, the moldability is adversely affected. When the blending amount of the paraffin oil is less than 50 parts by weight, the viscosity becomes high and injection molding becomes difficult, and when it exceeds 300 parts by weight, the hardness is lowered and the compression set is adversely affected, and oil bleeding is likely to occur.

  About the thermoplastic elastomer composition e2, the nitrogen-containing heterocyclic polyfunctional alcohol is 0.1 to 3.0 parts by weight, the hard polyolefin resin is 50 to 150 parts by weight with respect to 100 parts by weight of the maleated olefin elastomer. It is preferable that the amount of styrene-based thermoplastic elastomer is 20 to 150 parts by weight and the amount of paraffin oil is 50 to 300 parts by weight.

  If the blending amount of the hard polyolefin resin is less than 50 parts by weight, the viscosity becomes high and injection molding becomes difficult, and if it exceeds 150 parts by weight, the hardness after molding becomes too high. The blending amounts of the nitrogen-containing heterocyclic polyfunctional alcohol, the styrene thermoplastic elastomer, and the paraffin oil are the same as those of the cylindrical main body 2 described above.

  Moreover, it is preferable that the number average molecular weights of the paraffin oil used for the thermoplastic elastomer compositions e1 and e2 are 500 to 1,000. If the number average molecular weight is less than 500, the viscosity is too low and bleedout occurs, resulting in a problem of kneading failure. If the number average molecular weight exceeds 1000, the viscosity is too high and the hardness reduction effect is poor. This is because there is a problem.

It is a side view which illustrates the grip for golf clubs of this invention. It is AA sectional drawing of FIG. It is BB sectional drawing of FIG. It is a side view which illustrates the grip end part of FIG. It is CC sectional drawing of FIG. It is DD sectional drawing of FIG. It is explanatory drawing which illustrates the process of manufacturing the grip of FIG. It is a side view which illustrates the state which mounted | wore the shaft of the grip of FIG. It is EE sectional drawing of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Grip 2 Cylindrical main-body part 3 Grip end part 3a Cylindrical part 3b End surface 4 Projection part 5 Groove part 6 Through-hole 7 Shaft 8 Mold 8a Air vent hole 9 Cavity 10 Gate part

Claims (12)

  A grip end portion formed of a thermoplastic elastomer composition having an end face on one end side in the cylinder axis direction of the cylindrical portion, and a heat lower in hardness than the thermoplastic elastomer composition in which the grip end portion is thermally bonded to one end. A grip for a golf club comprising a cylindrical main body formed of a plastic elastomer composition, the grip end having a groove extending from one end to the other end in the cylinder axis direction on the inner peripheral wall of the grip end. A thermoplastic elastomer composition that has a through-hole in the end surface and forms the cylindrical main body portion covers the outer peripheral wall of the grip end and fills at least a part of the groove formed on the inner peripheral wall. Grip for golf club.   2. The golf club grip according to claim 1, wherein a plurality of the groove portions are provided at intervals in a cross section of the grip end portion, and the groove portions are linearly formed in a cylinder axis direction.   3. The golf club grip according to claim 1, wherein a thermoplastic elastomer composition forming the cylindrical main body is filled up to a position in the cylinder axial direction of the groove.   The cylindrical main body part and the grip end part contain a side chain containing a carbon-containing group and a hydrogen-bonded cross-linking site having a nitrogen-containing heterocycle, and a covalent bond cross-linking site having a carbon-containing group and a nitrogen-containing heterocycle. Compositions containing thermoplastic elastomers with other side chains, or covalent bonds with side chains containing carbon-containing groups and nitrogen-containing heterocycles, or side chains containing carbon-containing groups and nitrogen-containing heterocycles and nitrogen-containing heterocycles The golf club grip according to any one of claims 1 to 3, wherein the golf club grip is formed from any one of compositions containing a thermoplastic elastomer having a side chain containing a cross-linked site.   A thermoplastic elastomer composition in which the cylindrical main body portion is blended with a maleated olefin elastomer and a nitrogen-containing heterocyclic polyfunctional alcohol as a crosslinking agent, and a soft polyolefin resin, a styrene thermoplastic elastomer and paraffin oil as essential components. A thermoplastic elastomer in which the grip end portion is blended with a maleated olefin elastomer and a nitrogen-containing heterocyclic polyfunctional alcohol as a crosslinking agent, and a rigid polyolefin resin, a styrene thermoplastic elastomer and paraffin oil as essential components Formed from the composition, the hardness of the cylindrical body part is 40 to 80 (JIS-A), the hardness of the grip end part is 50 to 90 (JIS-A), and the grip end part as compared with the cylindrical body part Set the 100% modulus of the The 100% modulus of the part is 0.5 MPa to 4.0 MPa, the compression set is 60% or less, and the 100% modulus of the grip end part is 3.0 MPa to 6.0 MPa. Grip for golf club.   6. The soft polyolefin resin has a polypropylene block and an ethylene propylene block, the hard polyolefin resin is polypropylene, and the styrene thermoplastic elastomer is a hydrogenated styrene / isoprene / butadiene block copolymer. Grip for golf club.   A grip end portion having an end face on one end side in the cylinder axial direction of the cylindrical portion is molded in advance with a thermoplastic elastomer composition, and after the grip end portion is placed in a mold, the thermoplastic elastomer composition A thermoplastic elastomer composition having a low hardness is injected into the mold to form a cylindrical main body portion, and the grip end portion is thermally bonded to one end of the cylindrical main body portion. A thermoplastic elastomer composition produced by forming a groove portion extending from one end to the other end in the cylinder axis direction on the inner side of the peripheral wall of the grip end portion, and providing a through hole on the end surface of the grip end portion The golf club golf club is configured to cover at least a part of the groove formed on the inner side of the peripheral wall while covering the outer peripheral wall of the grip end portion. Method of manufacturing-up.   The golf club grip manufacturing method according to claim 7, wherein a plurality of the groove portions are provided at intervals in a cross section of the grip end portion, and are formed linearly in the cylinder axis direction.   9. The golf club grip manufacturing method according to claim 7, wherein a portion of the groove portion in the cylinder axial direction is filled with a thermoplastic elastomer composition forming the cylindrical main body portion.   The cylindrical main body part and the grip end part contain a side chain containing a carbon-containing group and a hydrogen-bonded cross-linking site having a nitrogen-containing heterocycle, and a covalent bond cross-linking site having a carbon-containing group and a nitrogen-containing heterocycle. Compositions containing thermoplastic elastomers with other side chains, or covalent bonds with side chains containing carbon-containing groups and nitrogen-containing heterocycles, or side chains containing carbon-containing groups and nitrogen-containing heterocycles and nitrogen-containing heterocycles The method for manufacturing a grip for a golf club according to any one of claims 7 to 9, wherein the golf club grip is formed from any one of compositions including a thermoplastic elastomer having a side chain containing a cross-linked site.   A thermoplastic elastomer composition in which the cylindrical main body portion is blended with a maleated olefin elastomer and a nitrogen-containing heterocyclic polyfunctional alcohol as a crosslinking agent, and a soft polyolefin resin, a styrene thermoplastic elastomer and paraffin oil as essential components. A thermoplastic elastomer in which the grip end portion is blended with a maleated olefin elastomer and a nitrogen-containing heterocyclic polyfunctional alcohol as a crosslinking agent, and a rigid polyolefin resin, a styrene thermoplastic elastomer and paraffin oil as essential components Formed from the composition, the cylindrical body has a hardness of 40-80 (JIS-A), the grip end has a hardness of 50-90 (JIS-A), and has a grip end compared to the cylindrical body. Set the 100% modulus of the The 100% modulus of the main body portion is 0.5 MPa to 4.0 MPa, the compression set is 60% or less, and the 100% modulus of the grip end portion is 3.0 MPa to 6.0 MPa. The manufacturing method of the grip for golf clubs as described.   12. The soft polyolefin resin has a polypropylene block and an ethylene propylene block, the hard polyolefin resin is polypropylene, and the styrene thermoplastic elastomer is a hydrogenated styrene / isoprene / butadiene block copolymer. A method for manufacturing a grip for a golf club.

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