JP2003210614A - Rubber-thread winding golf ball - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a rubber-thread winding golf ball which is excellent in spin characteristics and distance characteristics, is good in feeling and in addition, is good in the productivity of rubber-thread winding. <P>SOLUTION: The rubber-thread winding golf ball has a solid center, a rubber- thread winding layer and a cover and satisfies 330<5A+B+3C<356 (A is 36.0 to 39.0 mm) when the diameter of the solid center is defined as A mm, the amount of deformation in loading the solid center with a load from 10 to 130 kg as B mm and the Shore D hardness of the cover as C and the ball satisfies D/B>0.83 and E/D>0.89 when the amount of deformation in loading the rubber-thread winding core formed by covering the solid center with the rubber-thread winding layer with a load from 10 to 130 kg is defined as D mm and the amount of deformation in loading the final golf ball with a load from 10 to 130 kg as E mm. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wound golf ball having a wound layer formed on a solid center.

[0002]

2. Description of the Related Art Conventionally, a solid center having a large diameter has been proposed for the purpose of improving the flight performance (reducing spin) of a wound golf ball (JP-A-8-322963). Issue). A wound golf ball having improved flight performance by increasing the moment of inertia has also been proposed (Japanese Patent Laid-Open No. 9-2948).
30 publication).

However, with these improvements, the effect of improving the flight performance is still insufficient, and therefore, a wound golf ball having even better flight performance is desired.

The present invention has been made in order to meet the above-mentioned demands, and has good flight performance, good spin characteristics, good controllability, and good feeling, and further, production during winding. An object of the present invention is to provide a wound golf ball having good properties.

[0005]

Means for Solving the Problems and Modes for Carrying Out the Invention As a result of earnest studies to achieve the above-mentioned object, the present inventor has increased the solid center diameter and optimized the center deformation amount and the cover hardness. Limiting the amount of deformation of the wound core and the final ball formed by forming a wound layer on the solid center, the solid center is large, and the cover is soft,
We have found that by adopting a spin-type solid center pincushion structure, a pincushion golf ball can be obtained that has adequate spin performance especially for irons and approaches required by professional golfers and advanced players, and also has sufficient flight performance. The present invention has been completed.

Accordingly, the present invention provides the following wound golf ball. Claim 1: In a wound golf ball having a solid center, a wound layer covering the solid center, and a cover, the diameter of the solid center is Amm, and the deformation amount when a load of 10 kg from the initial stage to 130 kg is applied to the solid center. Bmm and C of Shore D hardness of the cover,
The following formula (1) 330 <5A + B + 3C <356 (1) (where A is 36.0 to 39.0 mm) is satisfied, and a wound core in which the above solid center is coated with a wound layer is used from the initial 10 kg to the final When the amount of deformation when a load of 130 kg is applied is Dmm and the amount of deformation when the final golf ball is applied with an initial load of 10 kg to a final 130 kg is Emm, the following equations (2) and (3) D / B> 0.83 (2) E / D> 0.89 (3) The thread wound golf ball characterized by the above-mentioned. Claim 2: The difference in specific gravity between the solid center and the cover is 0.
The thread-wound golf ball according to claim 1, which has a weight of 13 or less. Claim 3: The thread-wound golf ball according to claim 1 or 2, wherein the cover is formed mainly of polyurethane and has a Shore D hardness of 48 to 54. Claim 4: The solid center has a two-layer structure, and the initial 1
The thread-wound golf ball according to claim 1, 2 or 3, wherein the amount of deformation when a load of 0 kg to the final 130 kg is applied is 2.4 to 4.2 mm. Claim 5: The cover has an inner and outer two-layer structure, the Shore D hardness of the outer cover layer is 46 to 53, and the hardness difference between the inner cover layer and the outer cover layer is 5 or more in Shore D hardness. 4. The wound golf ball according to any one of 4 above.

The present invention will be described in more detail below.
The wound golf ball of the present invention includes a solid center, a wound layer that covers the solid center, and a cover.

In this case, the solid center may be a single layer or a multi-layer structure of two or more layers, but the innermost layer of the single-layer solid center or the multi-layer solid center is mainly composed of a rubber composition, especially polybutadiene. It is preferably formed from a rubber composition. The polybutadiene preferably contains cis-1,4 bonds in an amount of 40% or more, particularly 90% or more. In addition to polybutadiene, polyisoprene, styrene-butadiene rubber, diene rubber such as natural rubber may be blended.
It is preferably contained in an amount of 0% by weight or more, particularly 70% by weight or more.

In addition to the above-mentioned base rubber, the rubber composition of the present invention contains zinc salts of unsaturated fatty acids such as zinc acrylate and zinc methacrylate, magnesium salts of unsaturated fatty acids, other metal salts and triethanolpropane methacrylate. Etc., and a crosslinking agent such as unsaturated fatty acid such as methacrylic acid are preferably contained in an amount of 15 to 40 parts with respect to 100 parts (parts by weight, the same hereinafter) of the base rubber.

An organic peroxide such as dicumyl peroxide is preferably added to the base rubber in an amount of 0.
It is contained in the range of 1 to 3 parts. Further, in order to improve the resilience, a vulcanizing agent such as an organic sulfur compound such as pentachlorothiophenol zinc salt or diphenyl disulfide is used in an amount of 0.1 to 5 parts, particularly 0.2 to 3 parts, per 100 parts of the base rubber. It is preferable to mix in the range of parts.

Further, if necessary, an antiaging agent such as 2,2-methylenebis (4-methyl-6-tert-butylphenol) and a filler such as zinc oxide, barium sulfate or calcium carbonate for adjusting specific gravity can be used. It can be blended. In this case, the amount of the filler to be blended can be 130 parts or less with respect to 100 parts of the base rubber, but it is preferably less than 50 parts, more preferably 45 parts or less in terms of resilience and the like. It is particularly preferable that the amount is 40 parts or less. In addition, the lower limit of the blending amount of the filler is preferably 1 part or more, particularly preferably 3 parts or more, and may exceed 20 parts.

The above rubber composition is kneaded using a conventional kneading machine such as a Banbury mixer, a kneader and a roll, and the obtained compound is molded into a desired shape by compression molding, injection molding or the like. In this case, vulcanization can be performed at 130 to 180 ° C. for 10 to 60 minutes.

The outer layer of the solid center having a plurality of layers may be formed of the same rubber composition as described above, or may be formed of a thermoplastic resin such as an ionomer resin. However, the total diameter A of the solid center is 36.0 mm or more, preferably 36.5 mm.
mm or more and 39.0 mm or less, preferably 38.0 m
m or less, and initial 10k over the entire solid center
Deformation amount B when a final load of 130 kg is applied from g
Is 2.4 mm or more, particularly 2.8 mm or more and 4.2 m
It is preferably m or less, and particularly preferably 3.9 mm or less.

If the diameter of the center is too small, the effect of lowering the spin rate cannot be sufficiently obtained, and sufficient flight performance cannot be obtained. If it is too large, sufficient repulsion may not be obtained or durability may be deteriorated. If the deformation amount of the solid center is too small (too hard), the feel on impact becomes hard and the spin amount becomes too large, resulting in insufficient flight. Conversely, if the amount of deformation is too large (too soft), sufficient repulsion cannot be obtained and the required flight performance cannot be obtained.

The thread wound layer covering the solid center can be formed by winding a thread wound rubber by a known method using a known thread rubber, and in the present invention, the thickness of the thread wound layer is known. The gauge is relatively thin (in other words, the diameter of the solid center is relatively large). In this case, the wound core obtained by forming the wound layer on the solid center has an initial 1
The amount of deformation D when a load of 0 kg to the final 130 kg is applied is 2.5 mm or more, more preferably 2.7 mm or more, even more preferably 2.8 mm or more and 3.5 mm or less, more preferably 3.4 mm or less. , And more preferably 3.2 mm or less. If the deformation amount D is too small, the feel on impact becomes hard, and if the deformation amount D is too large, sufficient rebound cannot be obtained.

Further, the cover can be formed by using a thermoplastic resin such as an ionomer resin, a polyurethane elastomer or a polyester elastomer as a main material. In this case, the cover may have a single-layer structure or a multi-layer structure having two or more layers, but in the case of a single-layer structure, it is preferable to form the cover using a polyurethane elastomer as a main material, and have a Shore D hardness of 48. Above, especially above 49, below 54,
In particular, it is preferably 52 or less from the viewpoint of more advantageously achieving the object of the present invention. On the other hand, in the case of a multi-layer structure, the outer cover layer is preferably formed mainly of polyurethane elastomer, and its Shore D hardness is 46.
As described above, it is preferably 47 or more and 53 or less, particularly 50 or less. In this case, the inner cover layer can be formed by using a thermoplastic resin such as an ionomer resin, a polyurethane elastomer, or a polyester elastomer as a main material, but the hardness difference is 5 or more, particularly 5 to 15 as compared with the outer cover layer. It is preferable that the inner cover layer has a higher hardness, and the inner cover layer is formed so as to give the above hardness difference.

Further, it is preferable that the entire cover has a small difference in specific gravity from the entire solid center, and the difference in specific gravity is within 0.13, and particularly within 0.10 in order to improve the flight performance by increasing the moment of inertia. Is preferred.

Further, the total thickness of the cover is 0.8 mm or more, more preferably 1.0 mm or more, still more preferably 1.2 mm or more and 2.0 mm or less, more preferably 1.8 mm or less, and further preferably. It is preferably 1.6 mm or less.

The diameter and weight of the golf ball of the present invention can comply with the Rules of Golf and can be formed to have a diameter of 42.67 mm or more and a weight of 45.93 g or less.
Diameter is less than 42.8mm, weight is 45.0g, especially 4
It is preferably formed to 5.1 g or more.

The golf ball of the present invention has an initial 10
The deformation amount E when a load of from kg to the final 130 kg is applied is 2.2 mm or more, more preferably 2.4 mm or more,
More preferably 2.6 mm or more and 3.4 mm or less, more preferably 3.2 mm or less, still more preferably 3.1 m.
It is preferably m or less.

In the wound golf ball of the present invention, the diameter of the solid center is A mm, the amount of deformation when a load of 10 kg from the initial stage to 130 kg is applied to the solid center is B mm, and the Shore D hardness of the cover. Where C is C, the following formula (1) 330 <5A + B + 3C <356 (1) (where A is 36.0 to 39.0 mm) is satisfied, and the above solid center is covered with a bobbin layer. When the amount of deformation when a load of 10 kg to the final 130 kg is applied to the core is Dmm and the amount of deformation when the load of 10 kg to the final 130 kg is applied to the final golf ball is Emm, the following formulas (2) and ( 3) D / B> 0.83 (2) E / D> 0.89 (3) is satisfied.

If 5A + B + 3C is 330 or less, there is a problem that the amount of spin is too great to fly and the hit feeling is hard, and if it is 356 or more, sufficient spin performance cannot be obtained. The preferred range of 5A + B + 3C is 330 ≦ 5A
+ B + 3C ≦ 356, more preferable range is 335 ≦ 5A
+ B + 3C ≦ 350.

When D / B is 0.83 or less, sufficient spin performance cannot be obtained, or the rubber thread is easily broken during thread winding, resulting in poor productivity. On the other hand, when E / D is 0.89 or less, sufficient spin performance cannot be obtained. In this case, the preferable range of D / B is 0.83 ≦ D / B ≦ 1.03, and the further preferable range is 0.85 ≦ D / B ≦ 1.0. A preferable range of E / D is 0.90 ≦ E / D ≦ 1.02, and a further preferable range is 0.92 ≦ E / D ≦ 1.0.

The golf ball of the present invention has a large number of dimples formed on the cover surface in the same manner as a normal golf ball, but the total number of dimples is 350 or more, preferably 370 or more, more preferably 390 or more. The number is 500 or less, preferably 480 or less, more preferably 450 or less. Further, as the geometrical arrangement, octahedron, icosahedron arrangement, etc. can be adopted, and the dimple pattern is not limited to a circular shape, and may be a square type, a hexagon type, a pentagon type, a triangle type or the like. .

[0025]

INDUSTRIAL APPLICABILITY The wound golf ball of the present invention has excellent spin characteristics and flight distance characteristics, a good feeling, and
It has good bobbin productivity.

[0026]

EXAMPLES The present invention will be specifically described below by showing Examples and Comparative Examples, but the present invention is not limited to the following Examples.

[Examples and Comparative Examples] Solid centers having the properties shown in Table 3 were prepared by the compounding and vulcanization methods shown in Table 1.

[0028]

[Table 1] * 1 Peroxide (1) ... Dicumyl peroxide, trade name Park Mill D (manufactured by NOF Corporation) * 2 Peroxide (2) ... 1,1-bis (t-butylperoxy) -3,3,5 -Trimethylcyclohexane, trade name Perhexa 3M-40 (manufactured by NOF Corporation) * 3 Nocrac NS-6 (manufactured by Ouchi Shinko Chemical Industry Co., Ltd.) * 4 In E core (two-layer core), after vulcanizing the inner core (34 mm) An outer core (similar to the resin composition shown in Table 2) was injection molded.

Next, a wound core having the properties shown in Table 3 was formed from the obtained solid center by a conventional method using a rubber thread having the following composition and dimensions to obtain a wound core. Thread rubber composition Polyisoprene rubber 70 parts by weight Natural rubber 30 parts by weight Zinc white 1.5 parts by weight Stearic acid 1.0 parts by weight Vulcanization accelerator 1.5 parts by weight Sulfur 1.0 parts by weight Thread rubber dimension width 1.5 mm Thickness 0.55mm

Further, a cover having the properties shown in Table 3 was coated with the composition shown in Table 2. In this case, a pair of half-shell-shaped half cups was prepared in advance with the cover material (Example 5: in the double cover, the inner layer and the outer layer were respectively laminated after preparation), the wound core was encapsulated, and the wound core was heated at 140 to 170 ° C. Molded for 5-10 minutes.

[0031]

[Table 2] Pandex: Dainippon Ink and Chemicals, Thermoplastic Polyurethane Elastomer Nucrel: Mitsui / DuPont Polychemical, Ethylene / Methacrylic Acid / Acrylate Ester Terpolymer Co., Ltd. Surlyn: DuPont, Ionomer Resin Himilan: Mitsui / Dupont Poly Ionomer resin AM7311 manufactured by Chemical Co., Ltd .: manufactured by Mitsui DuPont Polychemical Co., Ltd., and ionomer resin (Note) were separately used after forming half cups and pasting them together. Resin Hardness (Shore D): ASTM D2240 Type D
Hardness measured by durometer JIS-K6253
Based on the above, the surface hardness of the resin sheet was measured, not the surface of the ball.

Next, the wound golf ball thus obtained was evaluated for wound productivity, flight, spin and feel by the following methods. The results are also shown in Table 3. Productivity during winding: ○: 2/50 or less yarn breakage during winding × × 3/50 or more yarn breakage during winding (measure the distance traveled when hit with W # 1, HS 45 m / s) ○ … 223m or more ×… less than 223m SW, HS 20m / s approach spin ○… 6000rpm or more ×… less than 6000rpm Feeling (W # 1 shot): Professional golfer 3
Sensory evaluation by humans ○… Good hit feeling ×… Hard

[0033]

[Table 3]

From the results shown in Table 3, the following can be recognized. Comparative Example 1 has a small solid center outer diameter W # 1
The spin amount is large and the flight distance at W # 1 is not sufficient. In Comparative Example 2, the value of the formula (1) is small, and the feel on impact is poor. In Comparative Example 3, the value of the formula (1) is large, and the spin amount during the SW approach is small. Comparative Example 4 has the formula (2)
Value is small, and thread breakage occurs frequently during winding, resulting in poor productivity. In Comparative Example 5, the value of the formula (3) is small, the SW approach spin is small, and the feel at the time of hitting is poor. On the other hand, the balls of the examples were free from yarn breakage, and had good flight, spin and feel.

Claims (5)

[Claims] 1. A wound golf ball having a solid center, a wound layer covering the solid center, and a cover,
Assuming that the diameter of the solid center is A mm, the amount of deformation when a load of 10 kg from the initial stage to the final 130 kg is applied to the solid center is B mm, and the Shore D hardness of the cover is C, the following formula (1) 330 <5A + B + 3C <356 (1 (However, A is 36.0 to 39.0 mm.) And the deformation amount when a load of 10 kg from the initial stage to 130 kg is applied to the wound core in which the solid center is covered with the wound layer is Dmm. , Emm is the amount of deformation when the final golf ball is loaded with an initial load of 10 kg to a final load of 130 kg, the following equations (2) and (3) D / B> 0.83 (2) E / D> 0. 89 (3) The thread wound golf ball characterized by the following. 2. The thread-wound golf ball according to claim 1, wherein the specific gravity difference between the solid center and the cover is 0.13 or less. 3. The cover is formed of polyurethane as a main material and has a Shore D hardness of 48 to 54.
The wound golf ball described. 4. The solid center has a two-layer structure, and the deformation amount is 2.4 to 4.2 mm when a load of 10 kg from the initial stage to 130 kg at the final stage is applied.
The wound golf ball described. 5. The cover has an inner and outer two-layer structure, the outer cover layer has a Shore D hardness of 46 to 53, and the hardness difference between the inner cover layer and the outer cover layer is 5 or more in Shore D hardness. 5. The thread-wound golf ball of claim 1.