JPS59129072A - Yarn wound golf ball - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] FIELD OF THE INVENTION The present invention relates to a thread-wound golf pole.

Thread-wound golf poles have traditionally been the mainstream for golf balls due to their high repulsion and excellent hitting feel.However, this thread-wound golf pole has a high repulsion force and provides an excellent feel when hitting the ball. The idea is to make the ball easier to work with and increase flight distance, so the moment of inertia of the ball is reduced, meaning the specific gravity of the center is increased, so that the ball is more likely to spin.

However, the relationship between spin gain and ball flight distance has not been clarified, and it has been empirically determined that the diameter of the center is 25~
Although the moment of inertia is small due to only 29 questions, and it is easy to cause puncture spin, in reality, the most important point in gaining flight distance is the point after the pole is launched. The ball's rotation at the time was greatly reduced from the initial amount of rotation, and the flight distance was not as long as expected.

In view of these circumstances, the present inventor has conducted various studies on the relationship between the structure of a thread-wound golf ball and its aerodynamic characteristics during flight, and by increasing the center diameter and decreasing the specific gravity, The mass distribution has been changed from the conventional high-density center type to the high-density outer shell type, and the moment of inertia of the pole has been increased to significantly attenuate the amount of rotation of the ball after it is launched and after passing the highest point. By eliminating this problem, we succeeded in making the ball's aerodynamic characteristics uniform from the initial stage to the time of fall, and dramatically improving the ball's flight performance.

In other words, the wooden invention has a center made of solid rubber,
Its diameter is 80-88 mm, specific gravity is 1.10 or less, and compressive strength is 1.0-2. The present invention relates to a thread-wound golf ball having a diameter of 84 f or less after winding the rubber thread (without a cover), a ball diameter of 41.148+or or more, and a ball weight of 45.91 or less.

In the present invention, the center is made of solid rubber and has a diameter in the range of 30 to 38 mm. If the diameter of the center exceeds 38 m, the winding will be completed before tension is applied to the rubber thread when winding the rubber thread, so the effect of winding the rubber thread will be lost, and the diameter of the center will be 80 m.
If it is less than m, the center of a conventional thread-wound golf ball (
This is because the effect of the present invention cannot be fully exerted when the diameter approaches 25 to 29 mm. The specific gravity of the center is LloJ, 'J, and the compressive strength is 1 with the amount of strain.
．． 0 = 2.0 gates. This means that if the specific gravity is greater than 1.10, the moment of inertia will be smaller than in conventional balls, resulting in poor flight performance, and if the compressive strength is less than the above range, the ball will be too hard, and the ball will have a core. If the compressive strength exceeds the above range, the ball will become too soft and the flight performance will deteriorate. In addition, in the present invention, the compressive strength is determined by assuming that the strain is 0 when an initial load of 8.8 kti is applied, and measuring how much strain is generated from the initial load when a load of 48.8 kti is applied, and comparing the strength based on the amount of strain. The smaller the amount of strain, the harder it is.

For example, a center with a diameter of 30 to 88 mm, a specific gravity of 1.10 or less, and a compressive strength of 1.0 to 2.0 in terms of strain, is made of, for example, 100 parts of Butashidaen rubber (parts by weight, below). A rubber composition containing 10 to 40 parts of zinc acrylate or zinc methacrylate, 2 to 10 parts of zinc oxide, and 0.5 to 5 parts of peroxide such as dicumyl peroxide is vulcanized (similar). It is obtained by heating and pressure molding).

The rubber thread attached to the center may be the same as conventional ones. For example, when natural rubber or a rubber composition containing natural rubber and polyisoprene rubber is mixed with an anti-aging agent, a vulcanization accelerator, sulfur, etc., is vulcanized. It is obtained by

In the present invention, the thread rubber is wound around the 1fI center to a value of 349 or less in a tentative state. This is 34F in that condition
This is because if it exceeds this, the outer shell side cannot be made to have a high specific gravity, and the moment of inertia of the ball cannot be increased. Further, in the present invention, the diameter of the golf ball obtained is 41.148 mm.
Therefore, the reserve will be reduced to 45.91 or less. This is the ball P
This is due to the request to pass GA standards.

Since the ball of the present invention has a lower specific gravity at the center than conventional balls, the cover contains a larger amount of weight adjusters such as zinc oxide, baricum sulfate, and titanium oxide than conventional balls, but other are the same as conventional ones, such as rubber compositions consisting of Barak (transpolyisoprene), veil crepe, zinc oxide, sulfur, vulcanization accelerators, etc., or ionomer resins (copolymerized with ethylene and methacrylic acid or acrylic acid). It is made from a composition consisting of a partially ionized product (commercially available products include Surlyn (trade name)) and Valicum sulfate, and the center of the cover is usually coated after winding the rubber thread. This is carried out by molding the cover composition into a hemispherical shell shape, wrapping the center of the wound rubber thread with two hemispherical shell-shaped covers, and vulcanizing at a high temperature for a short time.

Next, the present invention will be explained with reference to Examples.

Examples 1 to 3 and Comparative Examples 1 to 8 Rubber compositions having the compositions shown in Table 1 were used, and a diameter of 41.2.
Five types of wound golf balls of Iff were manufactured.

The amounts of each ingredient are determined by the Ministry of Reform. The center is vulcanized at 170"C x 20 minutes, and the thread rubber is vulcanized at 150°.
Vulcanization after cover coating was carried out at 140° CX for 20 minutes for transpolyisoprene and 160° for Surlyn.

Table 2 shows the specifications of the golf ball obtained and the flight test results.

As shown in Table 2, all of the balls of the present invention have long flight distances. On the other hand, in Comparative Example 8, the diameter of the center is the same as that of Example 1 of the present invention, but the specific gravity is large and the center has a high specific gravity type, so the moment of inertia is small and the distance cannot be achieved. . Comparative Example 2 Although a conventional thread-wound golf ball was used, the results were similar to those of Comparative Example 3. Although the ball of Comparative Example 1 has a center diameter slightly smaller than that of the ball of the present invention, its flight distance is shorter than that of the ball of the present invention. This is considered to be due to the low launch angle of the ball since the ball's ML when hit is similar to that of Comparative Example 20, which is a conventional thread-wound golf ball. Also, if the compressive strength of the center is 2.0 or more, it is not suitable because the ball hardness is too soft.

Patent applicant: Sumitomo Rubber Industries, Ltd. Procedural amendment (spontaneous) April II, 1980 Kazuo Wakasugi, Commissioner of the Japan Patent Office1, Indication of the case, Patent Application No. 3136 of 19832, Name of the invention: Thread-wound golf ball3, Relationship with the case of the person making the amendment Patent applicant address: 1-1 Tsutsui-cho, Chuo-ku, Kobe, Hyogo Prefecture
Name: Sumitomo Rubber Industries, Ltd. Representative: Kyohei Yokose 4, Agent: 550 Phone: 06 (531) 8
277 Address: 1-23 Kitahorie-chome, Nishi-ku, Osaka, Yoda Building, Yotsubashikan kg.''

(2) "5 types" on page 6, line 9 is corrected to "6 types."

(3) “Anti-aging*J” in the thread rubber section of Table 1 on page 7 of the same
IPPZJ is corrected with the anti-aging agent IPPDJ.

(4) The center compressive strength (mm) in the column of Comparative Example 2 in Table 2 on page 8 is r4.2 J.
and correct it.

(5) Correct the "appropriate" ball hardness in the Comparative Example 2 column of Table 2 on page 8 of the same page to [-soften].

that's all

Claims (1)

[Claims] 14 The center is made of solid rubber, the center has a diameter of 30 to 38 blades, a specific gravity of 1.10 or less, a compressive strength of between 1.0 and 2.0 in terms of strain, and after winding the rubber thread. condition (without cover) is 849 or less, the pole diameter is 41.1483ff or more and the ball market is 45.929
Below is a thread-wound golf pole.