JPH10127818A - Solid golf ball - Google Patents

Abstract

PROBLEM TO BE SOLVED: To get a sufficient flying distance and make soft the shot feeling by coating a solid core composed of a specified number of layers with a cover, and providing the intermediate layer of a solid core with a specified hardness value and making higher the hardness of the external layer than that of the intermediate layer. SOLUTION: A solid golf ball 3 is constituted of a solid core 1 composed of three layers and a cover 2 coating the solid core 1. The solid core 1 is constituted of the internal layer 1a, the intermediate layer 1b having JIS-C hardness 50-80, and the external layer 1c having a higher hardness than the intermediate layer 1b. When the hardness of the intermediate layer 1b is made lower than JIS-C hardness 50, it becomes too soft and the repulsive property becomes worse and the flying distance decreases. To the contrary, when it is made higher than JIS-C hardness 80, it becomes too hard and the shot feeling becomes worse. And when the hardness of the external layer 1c is made lower than the intermediate layer, a sufficient flying distance cannot be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a solid golf ball in which a solid core having a three-layer structure is covered with a cover.

[0002]

2. Description of the Related Art Generally, a two-piece solid golf ball in which a solid core having a single-layer structure is covered with a cover can provide a long flight distance, but has a drawback that the shot feeling is hard. Accordingly, a three-piece solid golf ball having a solid core having a two-layer structure has been developed to improve the above-mentioned disadvantages of a two-piece solid golf ball.

[0003] For example, a three-piece solid golf ball disclosed in Japanese Patent Application Laid-Open No. Sho 60-241264 has a solid core divided into an inner core and an outer core, and the inner core has a JIS-C hardness of 50 or more.
70, the outer core has a JIS-C hardness of 70 to 90,
The inner core is soft and the outer core is hard to obtain a soft feel at impact.

[0004]

However, when the impact force against the golf ball is large and the deformation of the ball extends to the inner core, it is impossible to obtain an appropriate spin for an optimum trajectory, and the flight distance Occurs. Further, in shots in which the outside of the ball is locally deformed, a good shot feeling is not always obtained due to the influence of the hardness of the outer core.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problem, and has as its object to provide a solid golf ball which can provide a sufficient flight distance and has a soft feel at impact.

[0006]

The solid golf ball of the present invention has a solid core 1 having three layers and a cover 2 covering the solid core 1, as shown in FIG.
It is composed of

The solid core 1 includes an inner layer 1a and JIS
-An intermediate layer 1b having a C hardness of 50 to 80;
And a jacket layer 1c having a hardness higher than that of the outer layer 1c.

If the hardness of the intermediate layer 1b is lower than JIS-C hardness 50, it becomes too soft, so that the resilience deteriorates and the flight distance decreases. Conversely, JIS-C hardness 8
If it is higher than 0, the ball becomes too hard and the shot feeling is deteriorated. The hardness of the intermediate layer 1b is set to a JIS-C hardness of 50 to 8
Even if it is set to 0, if the hardness of the jacket layer 1c is lower than the hardness of the intermediate layer 1b, a sufficient flight distance cannot be obtained.

Although the inner layer 1a is formed to be relatively hard, the hardness of the intermediate layer 1b may be lower than that of the intermediate layer 1b, and the JIS-C hardness is preferably 60 to 95.
The outer layer 1c preferably has a JIS-C hardness of 65 or more.

[0010] Each layer of the solid core 1 is usually formed from a rubber composition based on natural rubber and / or synthetic rubber, but is preferably composed of an ionomer resin, styrene, olefin, urethane, ester, or amide. A material containing a thermoplastic elastomer such as a system can also be used.

In the present invention, the intermediate layer 1b has a thickness of 1 to 1
3 mm, the combined diameter of the inner layer 1a and the intermediate layer 1b is 2
Although it is preferable to set the thickness to 1 to 39 mm, these ranges may be slightly changed. The diameters of the inner layer 1a and the solid core 1 are usually about 6 to 30 mm and about 37 to 41 mm, respectively, but are not limited to these ranges. If the dimensions (diameter or thickness) of each layer of the solid core 1 are set to dimensions that are far from normal,
The hardness distribution of the solid core 1 is not suitable, and the effect of the present invention cannot be obtained.

The cover 2 for covering the solid core 1 is usually formed of an ionomer resin or a resin composition based on a material containing the same, and the cover 2 has a thickness of a conventional two-piece solid golf ball or three-piece solid golf ball. The same thickness as the cover thickness of a solid golf ball (usually 1.3 to
2.8 mm).

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION In the solid golf ball of the present invention, the inner layer 1a of the solid core 1 has a diameter of 6 to 17 mm.
In the case of, the specifications of the solid core 1 shown in Table 1 are preferable.

[0014]

[Table 1]

Further, in order to prevent the ball from being excessively crushed during a shot in which the crush of the ball is large, it is preferable to make the hardness of the inner layer 1a higher than the hardness of the intermediate layer 1b. Even if the hardness is increased, the shot feeling is soft because the diameter of the inner layer 1a is small. A solid golf ball made of the solid core 1 of this specification can obtain an appropriate spin, particularly at the time of a shot in which the ball is significantly crushed, and the flight distance does not decrease.

Next, the solid golf ball of the present invention
When the inner layer 1a of the solid core 1 has a diameter of 17 to 30 mm, the specifications of the solid core 1 shown in Table 2 are preferable.

[0017]

[Table 2]

Further, in this solid golf ball, since the diameter of the inner layer 1a is larger than that of the specification shown in Table 1, the hardness of the inner layer 1a is lowered, and the intermediate layer 1b is provided further outside. Therefore, it is preferable to increase the hardness of the intermediate layer 1b. The solid golf ball made of the solid core 1 having this specification has a good shot feeling especially at the time of a shot in which the crush of the ball is small.

As described above, two types of solid golf balls having different characteristics depending on the specification of the solid core 1 can be obtained. The inner layer 1a, the intermediate layer 1b having a JIS-C hardness of 50 to 80, and the intermediate layer 1b With the solid core 1 having a three-layer structure composed of the outer layer 1c having a hardness higher than the hardness of the solid core 1, a high resilience can be obtained and the trajectory does not decrease due to a decrease in the number of spins. A flight distance can be obtained, and a soft shot feeling can be obtained by the soft mid layer 1b.

[0020]

EXAMPLES Examples 1 to 5 and Comparative Examples 2 and 3 Using the rubber compositions for the inner layer 1a, the intermediate layer 1b and the outer layer 1c according to the composition shown in Table 3, the composition of Example 1 in Table 4 was used. ~
5 and Comparative Examples 2 and 3, a solid core 1 having a three-layer structure having the diameter, weight, and hardness was produced. Using a resin composition for cover 2 containing 1.5 parts by weight of titanium dioxide with respect to 100 parts by weight of ionomer resin, solid core 1 was coated, polished and painted, and then subjected to Examples 1 to 5 and Comparative Examples Solid golf balls of Examples 2 and 3 were produced.

[0021]

[Table 3]

[0022]

[Table 4]

* 1 (carry), * 2 (number of spins): Wood No. 1 club (1
Measured by hitting at a club head speed of 40 m / sec according to W).

* 3 (feeling of hitting ball): A senior golfer
It was evaluated by hitting with Wood No. 1 Club (1W) and Iron No. 9 Club (9I). ◎ → very good, ○ → good, × → bad.

COMPARATIVE EXAMPLE 1 A conventional two-piece solid golf ball having a single-layer solid core produced by using a rubber composition having the composition shown in Table 3 was used in Examples 1 to 5 and Comparative Examples 2 and 3. It was produced by coating using a resin composition for a cover, polishing and painting.

For Examples 1 to 5 and Comparative Examples 1 to 3,
Table 4 shows the carry, the number of spins, and the feel at impact. As shown in Table 4, the solid golf balls of Examples 1 to 5
Compared with the conventional two-piece solid golf ball of Comparative Example 1, the flight distance was almost the same. In addition, the solid golf balls of Examples 1 to 5 were evaluated as having a good shot feeling.

On the other hand, in the solid golf ball of Comparative Example 2, the intermediate layer of the solid core was too hard and the shot feeling was poor. In the solid golf ball of Comparative Example 3, the outer layer of the solid core was softer than the intermediate layer, and a sufficient flight distance could not be obtained.

[0028]

According to the solid golf ball of the present invention, a sufficient flight distance can be obtained, and the poor hit feeling, which is a drawback of the two-piece solid golf ball, can be eliminated.

[Brief description of the drawings]

FIG. 1 is a sectional structural view of a solid golf ball of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Solid core 1a ... Inner layer 1b ... Intermediate layer 1c ... Outer layer 2 ... Cover

Claims (3)

[Claims] 1. A solid golf ball comprising a solid core having a three-layer structure composed of an inner layer, an intermediate layer and an outer layer, and a cover covering the solid core, wherein the intermediate layer has a JIS-C hardness. Set to 50-80,
A solid golf ball, wherein the hardness of the outer layer is set higher than the hardness of the intermediate layer. 2. The golf ball according to claim 1, wherein the inner layer has a JIS-C hardness of 60 to 95,
A solid golf ball, wherein the outer layer is set to a JIS-C hardness of 65 or more. 3. The golf ball according to claim 1, wherein the intermediate layer has a thickness of 1 to 13 mm, and a combined diameter of the inner layer and the intermediate layer is set to 21 to 39 mm. Solid golf ball.