KR101427669B1 - Multi layer golf ball - Google Patents

Abstract

The present invention relates to a multi-layered golf ball, and more specifically, to a multi-layered golf ball including a triple core layer formed by an inner core, an intermediate core disposed on a surface of the inner core, and an outer core disposed on a surface of the intermediate core, and a plurality of cover layers disposed on a surface of the triple core layer, wherein the inner core may be formed of glass beads or a mixture of cis-1,4 -polybutadiene rubber and a glass bubble. The multi-layered golf ball according to the present invention may have an increased spin rate and improved ball control. Also, the multi-layered golf ball has excellent rebound resilience, driving distance, and directional control when compared to a conventional golf ball. In addition, the multi-layered golf ball may have reduced air resistance to fly farther and have a soft hitting feel.

Description

A multi-layered golf ball

The present invention relates to a multi-layered golf ball, and more particularly, to a golf ball having a multi-layer structure, and more particularly, to a golf ball having a multi-layered golf ball comprising an inner core, an intermediate core formed on the inner core surface, Wherein the inner core comprises a mixture of glass beads or polybutadiene rubber having a cis-1,4 structure and glass bubbles.

An important element of a golf ball is distance and spin performance. The performance of such a golf ball is greatly influenced by the structure of the golf ball. The classification of the golf ball is as follows. A three-piece three-piece golf ball consisting of a two-piece golf ball with a single structure, a two-piece golf ball with a core and a cover surrounding the core, a double core and a cover, a core and a double cover A three-piece golf ball with three layers, a four-piece golf ball with one core and three layers of cover, a four-piece golf ball with a double core and a double cover, a four-piece golf ball with a three- Ball and so on.

A one-piece golf ball is made of high elasticity resin such as rubber without any distinction between core and cover, and it has a disadvantage in that the feel is good, the price is low, but the distance is not large.

The most common two-piece golf ball consists of a core and a cover. It is mainly made of a cover of ionomer or other resinous material on a core crosslinked by polybutadiene rubber with unsaturated carbonic acid or its salt. This two-piece golf ball has traditionally been classified as a distance golf ball, but has the disadvantage of less control performance due to less spin.

The core of a three-piece golf ball is a triple structure golf ball consisting of a solid core material, a solid core, and a cover of other resinous material such as ionomer or urethane. This three-piece golf ball has improved control performance compared to a two-piece ball, but has the disadvantage that the distance is reduced.

In addition, the four-piece golf ball is mostly composed of a double core double cover or a single core triple cover. The inner core, the first layer, is the driver's distance, the second layer is the distance from the wood or long iron shots, the third layer is the distance from the short irons, and the last layer covers are developed for filling and rotation of wedge shots and putters. . The four-piece golf ball has improved distance and control performance compared to a three-piece golf ball. However, the cover layer made of resin such as ionomer or polyurethane, which is less elastic than polybutadiene rubber, It was difficult.

US Pat. No. 5,879,244 proposes a method of molding a core layer under a cover with a resin to which a bismuth or bismuth alloy is added, and U.S. Patent No. 4,863,167 discloses a method of forming a core layer under a cover using tungsten, tungsten carbide, molybdenum, lead, lead oxide , Nickel or copper as a filler. US Pat. No. 5,984,806 (Sullivan et al.) Also suggested forming a multi-layered cover with a powder or strip of 10 to 325 mesh size. U.S. Patent No. 6,242,521 proposes a method of reacting zirconia with an ionomer resin to enhance the durability of the resin and improve the spin performance. However, in the above case, the materials used as the powder may come into contact with moisture during manufacturing to cause defects, and if a cover is scratched during use as a product, water may penetrate into the area to degrade the performance of the ball.

Recently, U.S. Patent No. 8,113,966 proposes a five-piece golf ball comprising a three-layered middle cover layer and a cover layer centering on the core layer, with different hardness and specific gravity of the center layer and hardness and / or specific gravity of the cover layer.

However, such a golf ball may be manufactured using a material having a hardness and / or a specific gravity opposite to that of the core layer and the cover layer, and may be formed as a three-piece, four-piece, and five- As a way of increasing, it has not achieved satisfactory repulsion elasticity, that is, the increase of the flying distance by the improved COR value and the proper spin performance.

U.S. Patent Publication No. 8,113,966 (published on April 2, 2012)

In order to solve the problems of the prior art as described above, the present invention provides a triple core layer comprising an inner core composed of a glass bead or a mixture of a polybutadiene rubber having a cis-1,4 structure and a glass bubble, And a golf ball having a multi-layer structure capable of improving the spin holding force and increasing the control.

It is another object of the present invention to provide a golf ball having a multi-layered structure which is improved in rebound resilience, distance and directionality as compared with the conventional golf ball, can reduce the air resistance and can send the ball farther, and has a soft hit feeling.

In order to attain the above object, the present invention provides a three-core layer comprising an inner core, an intermediate core formed on the inner core surface, and an outer core formed on the surface of the intermediate core, Wherein the inner core comprises a mixture of glass beads or polybutadiene rubber having a cis-1,4 structure and glass bubbles.

Particularly, the diameter of the glass beads constituting the inner core is preferably 5 to 10 mm.

The inner core made of a mixture of the cis-1,4-polybutadiene rubber and the glass bubble preferably has a diameter of 10 to 15 mm.

The glass bubbles may be mixed in an amount of 1 to 10 parts by weight based on 100 parts by weight of the polybutadiene rubber having a cis-1,4 structure.

The intermediate core or the outer core may be composed of a mixture of cis-1,4 polybutadiene rubber and bismuth.

The thickness of the intermediate core is 5 to 9.5 mm, and the thickness of the outer core is 5 to 9.5 mm.

The cover layer may be formed of an ionomer, a polyurethane resin, a thermoplastic rubber or the like, and may be formed of one or more layers.

The multi-layered golf ball according to the present invention can improve the ball control performance by improving the spin holding force, the spin amount, and the spin holding force. Further, the present invention has the advantages of being good in rebound resilience, distance and directionality as compared with the golf ball of the related art, reducing the air resistance, allowing the ball to be farther away, and having a soft hit feeling.

1 is a cross-sectional view illustrating an internal structure of a four-layer structure golf ball according to an embodiment of the present invention.
2 is a cross-sectional view illustrating an internal structure of a five-layer structure golf ball according to one embodiment of the present invention.
3 is a cross-sectional view illustrating the internal structure of a six-layer structure golf ball according to one embodiment of the present invention.

Hereinafter, the present invention will be described in detail.

A golf ball having a multi-layer structure according to the present invention comprises: an inner core; an intermediate core formed on the inner core surface; an outer core formed on the intermediate core surface; and a multi- Wherein the inner core is made of a mixture of a glass bead or a cis-1,4 polybutadiene rubber and a glass bubble.

Particularly, the golf ball of the present invention includes a triple-layered core composed of an inner core, an intermediate core and an outer core, and a glass bead or a cis-1,4 structure polybutadiene rubber and a glass bubble There is a big difference in using mixed mixtures.

First, a glass bead may be used as the inner core.

In the case of using the glass bead as an inner core (hereinafter referred to as a 'glass bead inner core'), since the specific gravity and hardness are high, the center of the golf ball is strengthened, And the friction force between the cover and the iron face is increased by the role of the central axis of the spin in the iron shot, so that the high spin can be generated. In addition, the glass bead inner core can reduce carry and side deviations, improving ball control performance, improving accuracy, and improving distance.

The glass beads used as the inner core preferably have a diameter of 5 to 10 mm and a specific gravity of 2.0 to 2.5 g / cm 3. When the diameter of the glass bead is less than 5 mm, the function of the central axis can not be performed during the reverse rotation, and when it exceeds 10 mm, the impact resistance may be weakened. If the specific gravity of the glass beads is less than 2.0 g / cm 3, it may be difficult to improve the flight performance. If the specific gravity of the glass beads is more than 2.5 g / cm 3, the drop angle may be decreased.

The inner core may be a mixture of a polybutadiene rubber having a cis-1,4 structure and a glass bubble.

The polybutadiene rubber of the cis-1,4 structure is a polybutadiene rubber having a cis-1,4 structure of at least 96%, preferably at least 98%. When the polybutadiene rubber having the cis-1,4 structure as described above is used, the rebound characteristics of the multi-layer structure golf ball of the present invention can be improved, which is better.

The glass bubble is a hollow filler having a low specific gravity and has a perfect spherical shape. Since it can increase the volume filling ratio as compared with the indefinite filler, there is no difference in physical properties according to the direction, more consistent golf balls can fly, The specific gravity is reduced, that is, the specific gravity of the golf ball center becomes smaller, and the magnitude of the inertial moment for improving the flying distance can be increased. When a mixture of the cis-1,4 structure polybutadiene rubber and glass bubbles is used as the inner core, the spin holding force of the ball is improved and the ball is allowed to fall at a gentle angle when it reaches the peak, thereby improving the flying distance .

In the case of an inner core (hereinafter referred to as a 'glass bubble inner core') composed of a mixture of the cis-1,4 structure polybutadiene rubber and a glass bubble, the specific gravity of the inner core It is important to use the content appropriately. Particularly, it is preferable that the glass bubble is contained in 1 to 10 parts by weight with respect to 100 parts by weight of the polybutadiene rubber having a cis-1,4 structure. When the content is less than 1 part by weight, The amount of the glass bubbles mixed with the polybutadiene rubber is excessive and the durability may be weakened.

If necessary, additives such as a rubber component, a co-crosslinking agent, a filler, an initiator, and an antioxidant may be further added to the core of the glass bubble.

As the rubber, natural rubber, isoprene rubber, SBR, Co-BR, Ni-BR and the like can be appropriately used in combination. As the co-crosslinking agent, an α, β-ethylenically unsaturated carboxylic acid or a metal salt thereof is preferred, but trimethylolpropane trimethacrylate or the like may be appropriately mixed and used if necessary. Examples of the α, β-ethylenically unsaturated carboxylic acid include acrylic acid and methacrylic acid. Examples of the metal salt include zinc acrylate and zinc methacrylate. The content of the α, β-ethylenically unsaturated carboxylic acid is 30 to 50 Can be used in parts by weight. As the filler, metal oxides such as zinc oxide and iron oxide, barium sulfate, silica, calcium carbonate, bismuth and glass bubbles can be used. When acrylic acid or methacrylic acid is used as the co-crosslinking agent, zinc oxide is preferably used . The content can be determined in consideration of the specific gravity or hardness of the internal core. In general, the filler is preferably used in an amount of 1 to 50 parts by weight based on 100 parts by weight of the rubber component.

Specific examples of the initiator include organic peroxides such as dicumyl peroxide, N-butyl-4,4'-bis (t-butylperoxy) valerate, bis (t-butylperoxyisopropyl) 1,1'-bis (t-butylperoxy) -3,3,5-trimethylcyclohexane and the like. The content of the initiator may be 0.2 to 3 parts by weight based on 100 parts by weight of the rubber component. If necessary, a coagent such as N, N'-m-phenylene dimaleimide may be used. As the antioxidant, 2,2'-methylene-bis (4-methyl-6-t-butylphenol) may be generally used and the content thereof may be 0.5 to 1.5 parts by weight based on 100 parts by weight of the rubber component have.

The inner core made of a mixture of the cis-1,4 polybutadiene rubber and glass bubbles preferably has a diameter of 10 to 15 mm. When the diameter of the inner core of the glass bubble is less than 10 mm, it is meaningless to discriminate the difference in weight. If the diameter is more than 15 mm, the total flight time is shortened and the trajectory is lowered.

An intermediate core is formed on the surface of the inner core made of a mixture of glass beads or cis-1,4 polybutadiene rubber and glass bubbles as described above, and an outer core is formed on the surface of the intermediate core, A core layer of the structure is formed.

When the inner core is made of a glass bead inner core made of glass beads, it is preferable that the outer core has a specific gravity higher than that of the intermediate core and a specific gravity lower than that of the inner core. That is, it is preferable that the inner core has a highest specific gravity, then the outer core has a higher specific gravity, and the intermediate core has a lowest specific gravity.

In the case of the triple core layer including the glass bead inner core, the inner core is made strong and heavy by forming the middle core, the outer core, and the inner core so that the dispersion of the energy transmitted to the golf ball when hit by the driver And a strong and heavy glass bead inner core acts as a central axis of the back spin when hitting with an iron, thereby increasing the frictional force between the cover and the iron face so that a high back spin can be generated. Also, when the outer core is made to have a specific gravity higher than that of the intermediate core, the specific gravity of the inner core is high, which improves the distance performance by reinforcing the spin holding force by compensating for the reduction of the moment of inertia.

In addition, when a glass bubble inner core composed of a mixture of a cis-1,4 structure polybutadiene rubber and a glass bubble is adopted, the intermediate core has a specific gravity higher than that of the inner core and a specific gravity lower than that of the outer core . That is, it is preferable to form a triple-layered core such that the specific gravity of the inner core is the lowest, the intermediate core is the next, and the specific gravity of the outer core is the highest.

In the case of the triple core layer including the inner core of the glass bubble, forming the inner core <middle core <outer core 'increases the inertia moment by making the outer core heavier than the inner core, To increase the flying time of the golf ball and to reduce the falling angle when the ball is dropped from the highest point of the flight, thereby increasing the distance.

The intermediate core and the outer core may be composed of a mixture of cis-1,4 polybutadiene rubber and bismuth. In addition, the components constituting the intermediate core and the outer core may further include general rubber, co-crosslinking agent, filler, initiator, antioxidant, and the like.

The polybutadiene rubber of the cis-1,4 structure is a high-cis polybutadiene rubber having a cis-1,4 structure of at least 96%, preferably at least 98%. When the polybutadiene rubber having the cis-1,4 structure as described above is used, the rebound characteristics of the multi-layer structure golf ball of the present invention can be improved, which is better. The polybutadiene rubber of the cis-1,4 structure is preferably used singly, but natural rubber, isoprene rubber, SBR, Co-BR and Ni-BR may be suitably used in combination.

The bismuth increases the moment of inertia so that the spin is maintained for a long time and acts to generate high repulsive force even at low hardness. In particular, when the bismuth is used in the outer core, the density is increased by 3 to 3.5% expansion at room temperature, so that the force energy generated at the time of impact can be easily transmitted to the inner core.

The bismuth is preferably contained in 1 to 5 parts by weight in 100 parts by weight of the polybutadiene rubber having the cis-1,4 structure. If the content is less than 1 part by weight, there is no discrimination against weight. If the content is more than 5 parts by weight, bismuth having a large specific gravity is excessively contained, which makes it difficult to match the weight of the golf ball and durability may be weakened.

The above-mentioned co-crosslinking agent, filler, initiator and antioxidant can be used in the same kind and composition as those described in the core of the glass bubble. However, in the case of the co-crosslinking agent, it is preferable to use the intermediate core in an amount of 35 to 50 parts by weight based on 100 parts by weight of the base rubber and 20 to 40 parts by weight in the case of the external core.

The core layer having the triple structure as described above is sufficiently blended by using an internal mixer, twin roll mill, or the like, which is a conventional blending machine, and then placed in a mold of a predetermined size to form a core inside the glass bubble In the case of the core, only the glass beads constitute the inner core), the core may be formed into an intermediate core to surround the surface of the inner core, and the outer core may be formed to surround the surface of the intermediate core.

In the molding process, a suitable temperature and time are required for the crosslinked reaction to occur in order to obtain a proper hardness distribution of the inner core of the glass bubble, the middle core, and the triple core layer of the outer core. There is an initiator suitable for each type of co-crosslinking agent and exhibits an appropriate hardness distribution while minimizing the amount of the crosslinking agent when crosslinking at a temperature 10 to 50 DEG C higher than the decomposition starting temperature of the initiator.

The intermediate core may have a thickness of 5 to 9.5 mm. When the thickness of the intermediate core is less than 5 mm, the durability may be weakened due to the low impact resistance. If the thickness exceeds 9.5 mm, The durability can be weakened. The thickness of the outer core is preferably 5 to 9.5 mm. If the thickness of the outer core is less than 5 mm, the impact resistance may be reduced and the durability may be weakened. If the thickness is more than 9.5 mm, The impact resistance may be reduced and the durability may be weakened.

As described above, the cover layer may be formed so as to surround the surface of the triple core layer composed of the inner core (glass bead inner core or glass bubble inner core), the middle core and the outer core to produce a multi-layered golf ball.

As the material of the cover layer, a resin having excellent weather resistance, light resistance, and impact resistance is used, and inorganic fillers, pigments, and the like may be appropriately used according to the purpose.

The cover layer is preferably formed in a multi-layer structure. In particular, the cover layer is preferably formed of one to three layers, and the thickness of each layer can be appropriately adjusted.

When the cover layer is formed as one layer, the thickness of the cover may be 0.5 to 1.6 mm. When the cover layer is formed of two layers, the inner cover layer may be 0.5 to 1.2 mm and the outer cover layer may be 0.5 to 1.6 mm. When the cover layer is formed of three layers, the inner cover layer may be 0.5 to 1.2 mm, the middle cover layer may be 0.5 to 1.2 mm, and the outer cover layer may be 0.5 to 1.6 mm.

The cover layer can be generally formed by using an ionomer, a polyurethane resin, a thermoplastic rubber or the like used for the cover layer. The ionomer resin may be appropriately mixed with various ionomer resins as needed. For example, HI-MILAN 1706, 1605 of Mitsui Polychemical Co., Ltd., ESCOR EX951, 562, 900 of EXXON, etc. can be used. As the polyurethane resin, a thermoplastic polyurethane resin, a thermosetting polyurethane resin, or the like can be used. As the thermoplastic rubber, SBS (styrene-butadiene-styrene), SEBS (styrene-ethylene / butylene-styrene triblock copolymer) .

As a method of forming the cover layer from a polyurethane resin, an injection molding method is generally used for the thermoplastic polyurethane resin, and a cast molding method is used for the thermosetting polyurethane resin.

As the method of forming the cover layer from an ionomer resin, an injection molding method or a compression molding method is generally used. Finally, the golf ball is painted on the cover to produce a multi-layered golf ball made of a triple core according to the present invention, such as 4PC, 5PC, 6PC.

Hereinafter, a multi-layered golf ball according to the present invention will be described in detail with reference to the accompanying drawings. The multi-layer golf ball of the present invention described below can be implemented in various different forms, and is not limited to the multi-layer golf ball described herein.

1 is a cross-sectional view of a golf ball having a four-layer structure according to an embodiment of the present invention. Referring to FIG. 1, a golf ball having a four-layer structure according to an embodiment of the present invention includes a triple-layered core layer and a single cover layer.

The triple core layer includes an inner core 10 forming a central portion, an intermediate core 20 formed to surround the surface of the inner core 10, and an outer core 30 formed to surround the surface of the intermediate core 20 ). &Lt; / RTI &gt;

In particular, the inner core 10 is preferably made of a mixture of a glass bead or a mixture of a polybutadiene rubber having a cis-1,4 structure and a glass bubble in order to improve accuracy and ensure a distance.

In the case of the inner core 10 made of glass beads, the inner core 10 may have a thickness of 5 to 10 mm. When the inner core 10 is made of a mixture of a cis-1,4 polybutadiene rubber and a glass bubble, Mm.

The intermediate core 20 and the outer core 30 may each have a thickness of 5 to 9.5 mm.

The cover layer 40 is formed to have a thickness of 0.5 to 1.6 mm so as to surround the surface of the triple-layer, and a plurality of dimples are formed on the outer surface of the cover layer.

2 is a cross-sectional view of a five-layer golf ball according to one embodiment of the present invention. Referring to FIG. 2, a golf ball having a five-layer structure according to an embodiment of the present invention is composed of a triple core layer and a double cover layer.

The triple core layer is the same as that described with reference to FIG. 1, and a detailed description thereof will be omitted.

The double cover layer is composed of an inner cover layer 50 and an outer cover layer 40 which are formed so as to surround the surface of the triple core layer.

The inner cover layer 50 is formed on the surface of the triple core layer so as to surround the triple core layer with a thickness of 0.5 to 1.2 mm. The outer cover layer 40 is formed on the surface of the inner cover layer 50 to cover the inner cover layer 50 with a thickness of 0.5 to 1.6 mm and the outer cover layer 40 has a plurality of dimples .

3 is a cross-sectional view of a six-layer golf ball according to one embodiment of the present invention. Referring to FIG. 3, a golf ball having a six-layer structure according to an embodiment of the present invention is composed of a triple-layered core layer and a triple-layered cover layer.

The triple core layer is the same as that described with reference to FIG. 1, and a detailed description thereof will be omitted.

The triple cover layer is composed of an inner cover layer 50, an intermediate cover layer 60, and an outer cover layer 40 which are formed so as to surround the surface of the triple core layer.

The inner cover layer 50 is formed on the surface of the triple core layer so as to surround the triple core layer with a thickness of 0.5 to 1.2 mm. An intermediate cover layer 60 is formed on the surface of the inner cover layer 50 to cover the inner cover layer 50 with a thickness of 0.5 to 1.2 mm. An outer cover layer 40 is formed to cover the intermediate cover layer 60 with a thickness of 1.6 mm. At this time, a plurality of dimples are formed on the outer surface of the outer cover layer 40.

As described above, the multi-layered golf ball of the present invention comprises a triple-layered core layer and a multi-layered cover layer having excellent rebound resilience and distance spin performance through control of the size, specific gravity, and hardness of the triple core cores .

The multi-layered golf ball of the present invention uses a glass bead on the inner core, which is the center of the triple-core layer, to strengthen the center of the golf ball. In the driver's shot, the force energy transmitted from the golf club to the golf ball The distance between the cover and the iron face can be increased to increase the distance between the cover and the iron face, and the high spins can be generated in the iron shot as the central axis of the spin. In addition, the glass bead inner core can reduce carry and side deviations, improving ball control performance and improving accuracy. The multi-layer structure golf ball of the present invention can increase the volume filling rate by forming the inner core, which is the center of the triple-core layer, with a mixture of the cis-1,4 structure polybutadiene rubber and the glass bubble, There is no difference, a more consistent golf ball flight is possible, the specific gravity of the inner core is reduced, that is, the specific gravity of the golf ball center becomes smaller, the inertia moment for improving the flying distance can be increased, The spin holding force is improved to reach the highest point, and when falling, it is allowed to fall at a gentle angle, thereby improving the flying distance.

Hereinafter, the present invention will be described in more detail with reference to examples. These embodiments are for purposes of illustration only and are not intended to limit the scope of protection of the present invention.

Example 1

A glass bead having a diameter of 5 mm and a specific gravity of 2.5 g / cm3 was used as an inner core.

1 part by weight of bismuth, 0.5 part by weight of Antioxidant 2246, 2 parts by weight of ZnO, 28 parts by weight of ZA, 1 part by weight of DIPP and 2 parts by weight of TMCH were added to 100 parts by weight of polybutadiene rubber having a cis- The mixture was uniformly mixed in a twin roll mill to prepare a rubber mixture for an intermediate core.

An intermediate core was formed and formed on the surface of the glass bead, which is the inner core, by using the prepared rubber mixture for the intermediate core.

Then, 2 parts by weight of bismuth, 0.5 part by weight of Antioxidant 2246, 27 parts by weight of ZnO, 30 parts by weight of ZA, 1 part by weight of DIPP and 1 part by weight of TMCH were added to 100 parts by weight of polybutadiene rubber having a cis- 2 parts by weight were uniformly mixed to prepare a rubber mixture for an external core.

An outer core was formed and formed on the surface of the intermediate core by using the rubber mixture for the outer core to form a core layer of a triple structure.

Then, 40 parts by weight of ESCOR EX951 and 60 parts by weight of ESCOR EX900 were used as an ionomer resin to cover the core layer surface of the triple structure to form a cover layer. At this time, a plurality of dimples were formed in the cover layer.

Example 2

The procedure of Example 1 was repeated except that the composition of the following Table 1 was used.

Example  3

5 parts by weight of glass bubbles, 0.5 part by weight of Antioxidant 2246, 2 parts by weight of ZnO, 28 parts by weight of ZA, 1 part by weight of DIPP, and 1 part by weight of TMCH 2 were added to 100 parts by weight of polybutadiene rubber having a cis- The mixture was uniformly mixed in a twin mill and then placed in a mold of 10 mm to form a glass bubble inner core.

Subsequently, 1 part by weight of bismuth, 0.5 part by weight of Antioxidant 2246, 15 parts by weight of ZnO, 28 parts by weight of ZA, 1 part by weight of DIPP and 1 part by weight of TMCH were added to 100 parts by weight of polybutadiene rubber having a cis- 2 parts by weight were uniformly mixed to prepare a rubber mixture for an intermediate core.

An intermediate core was formed and formed on the surface of the core inside the glass bubble by using the prepared rubber mixture for the intermediate core.

Then, 2 parts by weight of bismuth, 0.5 part by weight of Antioxidant 2246, 30 parts by weight of ZnO, 28 parts by weight of ZA, 1 part by weight of DIPP and 1 part by weight of TMCH were added to 100 parts by weight of polybutadiene rubber having a cis- 2 parts by weight were uniformly mixed to prepare a rubber mixture for an external core.

An outer core was formed and formed on the surface of the intermediate core by using the rubber mixture for the outer core to form a core layer of a triple structure.

Then, 40 parts by weight of ESCOR EX951 and 60 parts by weight of ESCOR EX900 were used as an ionomer resin to cover the core layer surface of the triple structure to form a cover layer. At this time, a plurality of dimples were formed in the cover layer.

Example 4

The same procedure as in Example 3 was carried out except that the composition of the following Table 2 was used.

Example 5

In Example 1, an inner cover layer was formed using 50 parts by weight of HI-MILAN 1706 and 50 parts by weight of ESCOR EX951, and 40 parts by weight of ESCOR EX951 and 60 parts by weight of ESCOR EX900 were coated on the surface of the inner cover layer Except that an outer cover layer was formed to form a cover layer having a double structure.

Example 6

In Example 1, 50 parts by weight of HI-MILAN 1706 and 50 parts by weight of ESCOR EX951 were used to form an inner cover layer. On the surface of the inner cover layer, 50 parts by weight of ESCOR EX951 and 50 parts by weight of ESCOR EX900 Except that an intermediate cover layer was formed and an outer cover layer was formed on the surface of the intermediate cover layer using 40 parts by weight of ESCOR EX951 and 60 parts by weight of ESCOR EX900 to form a cover layer of a triple structure. .

Comparative Example 1

A conventional golf ball having the composition shown in Table 3 below was used.

In order to measure the degree of improvement in accuracy when glass beads were used as internal cores, the carry and test deviation were measured by repeating several tests at 110 Mph using the golf balls manufactured in Examples 1 and 2 to measure carry deviation and side deviation, Are shown in Table 4 below.

division Example 1 Example 2 Comparative Example 1 H / S (Mph) 110 110 110 Spin rate (rpm) 2,521 2,615 2,444 Peak (m) 22.5 22.9 21,4 carry (m) 246.5 246.6 244.7 Total distance (m) 265.0 264.2 264.4 Carry deviation (m) 5.6 6.4 8 Side deviation (m) 13.3 14.2 29.9

As shown in Table 4, in Examples 1 and 2 in which the inner core was formed with glass beads according to the present invention, it was confirmed that the carry deviation and the side deviation were lower than those of the conventional golf ball. Using glass beads as a ball increases the ball control, and when hit the ball with the same force, it shows a certain result and accuracy will be improved.

When a mixture of a cis-1,4-polybutadiene rubber and a glass bubble was used as an internal core, the golf balls prepared in Examples 3 and 4 were used to measure the degree of distance improvement, The test was repeated, and the average value thereof is shown in Table 5 below.

division Example 3 Example 4 Comparative Example 1 H / S (Mph) 110 110 110 Starting angle (deg) 9.0 9.0 9.1 Peak (m) 21.9 21.3 22.2 landing angle (deg) 29.8 27.8 30.6 carry (m) 247.9 245.2 245.5 Total distance (m) 267.6 267.7 264.2

As shown in Table 5, in Examples 3 and 4 in which an inner core was formed using a mixture of a polybutadiene rubber having a cis-1,4 structure and a glass bubble according to the present invention, landing As a result, it can be seen that when a mixture of cis-1,4 polybutadiene rubber and glass bubble is used as an internal core, the ball slopes more slowly when falling from the peak, . Particularly, Example 4 in which a larger amount of glass bubbles were mixed with the polybutadiene rubber having a cis-1,4 structure as an internal core showed a smaller landing angle as compared with Example 3.

Although the present invention has been described in terms of the preferred embodiments mentioned above, it is possible to make various modifications and variations without departing from the spirit and scope of the invention. It is also to be understood that the appended claims are intended to cover such modifications and changes as fall within the scope of the invention.

C: Center of the sphere
10: Internal core
20: intermediate core
30: outer core
40: Cover, outer cover
50: inner cover
60: middle cover

Claims (7)

A triple core layer comprising an inner core, an intermediate core formed on the inner core surface, and an outer core formed on the intermediate core surface, and a cover layer formed on a surface of the triple core layer,
The inner core is made of a mixture of glass beads or a mixture of a polybutadiene rubber having a cis-1,4 structure and a glass bubble,
Wherein the glass bead has a diameter of 5 to 10 mm and a specific gravity of 2.0 to 2.5 g / cm 3. delete The method according to claim 1,
Wherein the inner core composed of a mixture of the cis-1,4 polybutadiene rubber and glass bubbles has a diameter of 10 to 15 mm. The method according to claim 1,
Wherein the glass bubble is mixed in an amount of 1 to 10 parts by weight based on 100 parts by weight of a polybutadiene rubber having a cis-1,4 structure. The method according to claim 1,
The intermediate core and the outer core are made of a mixture of a polybutadiene rubber having a cis-1,4 structure and bismuth, and the bismuth is added in an amount of 1 to 5 parts by weight per 100 parts by weight of a polybutadiene rubber having a cis- And the golf ball is mixed. The method according to claim 1,
Wherein the intermediate core has a thickness of 5 to 9.5 mm and the outer core has a thickness of 5 to 9.5 mm. The method according to claim 1,
Wherein the cover layer is made of at least one selected from the group consisting of an ionomer resin, a polyurethane resin and a thermoplastic rubber, and the cover layer is formed of one or more layers.

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