JPH09300361A - Mold for manufacturing golf ball and manufacture of golf ball employing this mold - Google Patents

Abstract

PROBLEM TO BE SOLVED: To maintain a good mold releasing property for a long period of time, and reproduce the mold foundation material without making defects to the mold foundation material at the time when the mold releasing property is lowered. SOLUTION: A composite plated skin film 4 having fluorine contained resin particles in the nickel matrix 2 in an eutectoid-dispersed manner is formed on the cavity surface of a mold and, furthermore, fluorine contained resin is applied and heated on the composite plated skin film 4, thus forming a fluorine contained resin layer 5 put together with fluorine contained resin exposed on the composite plated skin film 4. In this process, high qualified golf balls can be manufactured for a log period of time.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mold for producing a golf ball for molding a cover layer and a core ball of a one-piece golf ball, a solid golf ball of two-piece or three-piece or more, or a thread-wound golf ball, and the mold. More specifically, the method for producing a golf ball will be described in more detail. A mold for producing a golf ball, which is excellent in mold releasability and durability and can efficiently produce a high quality golf ball, and a golf using the mold. The present invention relates to a ball manufacturing method.

[0002]

BACKGROUND OF THE INVENTION Golf balls include one-piece golf balls consisting of a single rubber layer, solid golf balls such as a two-piece golf ball having a cover on the inner core sphere, and a solid golf ball on the inner core sphere. There is a thread-wound golf ball in which a thread rubber is wound and a cover is further covered on the thread rubber.These golf balls each have a molding material supplied into a spherical cavity of a mold composed of a pair of split molds, and the inner core Manufactured by molding the ball, cover or the entire one-piece golf ball.

[0003] Here, the above-mentioned mold can be separated into a pair of split molds in which a base body made of carbon steel, beryllium-copper alloy or the like having a hemispherical concave cavity is plated with chromium or nickel. A type in which spherical cavities are formed inside by joining, and a rubber material is supplied into the spherical cavities to heat-vulcanize and form the inner core spheres and one-piece golf balls,
A type in which an inner core sphere is placed in a cavity and a thermoplastic resin such as an ionomer resin is injection-supplied into the cavity to inject a cover around the inner core sphere or a wound core, or a rubber thread on the inner core sphere. A type in which a cover layer is formed around the wound core by placing a wound core wound with a thermoplastic resin material molded in a half cup shape in the cavity and heat-pressing it. There is.

In this case, the ionomer resin of the cover material and the rubber material for obtaining the inner core spheres, which are supplied into the mold, contain a component such as an acrylic acid group or a methacrylic acid group which easily adheres to the metal. Therefore, the molding material adheres to the cavity surface of the mold during molding, and the golf ball and inner core sphere cannot be smoothly taken out from the mold after molding,
It may damage or damage the molded product. For this reason, a mold release agent is usually applied to the cavity surface of the mold before molding to prevent the molding material from adhering.

However, the mold release agent applied to the cavity surface of the mold is immediately peeled off due to the strong adhesiveness of the molded product, and the mold release agent is applied every 3 to 5 times of molding. However, the method of improving the releasability by applying the release agent has a problem in work efficiency.

It has also been proposed to coat the cavity surface of the mold with a fluororesin such as polytetrafluoroethylene (PTFE) (so-called Teflon coating). The mold with such coating is
It is possible to maintain the releasability for a relatively long time, but if the releasability deteriorates and it is necessary to replace the coating layer, the old coating layer must be removed by blasting, etc. At this time, there is a problem that the die base material is damaged and the precision of the die is lowered.

Furthermore, when nickel plating is applied to the die base material, PTFE particles are co-deposited in the nickel plating film, and as shown in FIG. It has also been proposed to form a composite plating film 4 in which particles 3 are uniformly dispersed on the cavity surface of the mold base 1 (Japanese Patent Laid-Open No. 5-220241). In this mold, a part of the fluororesin particles 3 is exposed on the surface of the composite plating film 4, and good release properties are obtained by the fluororesin particles exposed on the surface of the composite plating film 4 in this manner. At the same time, the composite plating film 4 can be easily removed and replaced by a solvent such as a release agent for electroless nickel plating without damaging the mold substrate 1.

However, although the mold having such a composite plating film 4 exhibits a good mold releasability at the initial molding, the mold releasability deteriorates as the molding is repeated, and the mold releasing durability is It is about ⅕ of the mold with the Teflon coating described above, and there is a problem in mold release durability as in the method of applying the mold release agent.

That is, as shown in FIG. 4A, the fluororesin particles exposed on the surface of the composite plating film 4 are
Most of the particles are embedded in the nickel matrix 2, and only a part of the particles are exposed on the surface of the coating film 3a.
And the particles 3b in which most of the particles are exposed from the surface of the coating film 4, but most of the particles 3b are exposed by a molding material having strong adhesiveness during repeated molding and releasing.
b is peeled off from the surface of the coating 4 and, as shown in FIG. 6B, most of the particles are only the particles 3b embedded in the nickel matrix 1, and the fluororesin particles exposed on the surface of the coating 4 are largely formed. Will be reduced to. Then, the area of direct contact between the molding material and the nickel matrix 2 at the time of molding becomes large, and due to the strong adhesiveness between the molding material and the nickel matrix 2, the releasability is significantly reduced.

The present invention has been made in view of the above circumstances, and it is possible to maintain good mold releasability for a long period of time, and when the releasability is lowered, it is easy to do without damaging the mold base material. It is an object of the present invention to provide a mold for producing a golf ball which can be regenerated into a new type, and a method for producing a golf ball using the mold.

[0011]

Means for Solving the Problems and Modes for Carrying Out the Invention In order to achieve the above object, the present inventor has proposed a composite plating film in which fluororesin particles are eutectically dispersed in a nickel matrix on the cavity surface of a mold. When the inner core sphere of a golf ball, a cover, or a one-piece golf ball is molded by using this mold by forming a fluororesin layer by further coating a fluororesin thereon and heat-treating The fluororesin layer exhibits good mold releasability, and these molded products can be satisfactorily demolded without adhering to the cavity surface of the mold, ensuring molded products with excellent surface conditions. In addition, the good releasability can be maintained for a long period of time, and when the releasability is lowered, the composite plating film is peeled off with a solvent to prevent the mold from being damaged. It can be performed to place over the can coating and fluororesin layer, found that it is possible to efficiently produce over a high-quality golf balls to long, and completed the present invention.

Therefore, according to the present invention, a pair of split molds are separably joined to each other to form a spherical cavity therein, and a molding material is supplied into the cavity to form a one-piece golf ball or an inner core of a golf ball. In a golf ball manufacturing mold for molding balls and covers, a composite plating film in which fluororesin particles are eutectically dispersed in a nickel matrix is formed on the cavity surface, and a fluororesin is further applied on the composite plating film. And heat treatment to form a fluororesin layer integrated with the exposed fluororesin particles on the composite plating film, and a mold for golf ball production, and a pair of split molds. A one-piece golf ball or a golf ball of a one-piece golf ball is prepared by supplying a molding material into a mold that is separably joined to form a spherical cavity inside. A method of manufacturing a golf ball forming a mononuclear or cover, to provide a method of manufacturing a golf ball, which comprises using a golf ball manufacturing mold of the present invention as a mold.

Hereinafter, the present invention will be described in more detail.
As shown in FIG. 1, the mold for producing a golf ball of the present invention forms a composite plating film 4 in which fluororesin particles 3 are uniformly dispersed in a nickel matrix 2 on a cavity surface of a mold base material 1. Then, a fluororesin is applied on the composite plating film 4 and heat-treated to form a fluororesin layer 5
Is formed.

The mold base 1 may be any metal that can be plated, such as carbon steel, beryllium-copper alloy,
A mold formed of a usual metal material such as stainless steel or copper can be used. Although not particularly shown,
This mold is composed of a pair of split molds having a hemispherical cavity, and these split molds are separably joined to each other to form a spherical cavity inside. The composite plating film 4 and the fluororesin layer 5 are formed on the cavity surface of the die. In the case of a mold for molding a one-piece golf ball or a cover for a golf ball, a large number of small protrusions for forming dimples can be formed on the cavity surface of the mold.

Next, the nickel matrix 3 forming the composite plating film 4 formed on the cavity surface of the mold base 1 is obtained by either electroplating or electroless plating. A plating film may be used, but a plating film obtained by an electroless plating method is preferable because a particularly uniform film can be obtained. The nickel matrix 3 may be made of nickel as a main material, and nickel such as nickel-phosphorus alloy, nickel-copper-phosphorus alloy, nickel-boron alloy, cobalt-nickel alloy, and nickel-molybdenum-phosphorus alloy. It may be an alloy with other metals or substances.

The fluororesin particles 3 to be co-deposited in the nickel matrix 2 are polytetrafluoroethylene (PTFE) particles, tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer (PF).
A) particles, tetrafluoroethylene-hexafluoropropylene copolymer (FEP) particles, tetrafluoroethylene-ethylene copolymer (ETFE) particles and the like can be mentioned, and particularly PTFE particles and FEP particles are preferably used. The particle size of the fluororesin particles 3 is not particularly limited, but is preferably 0.1 to 2 μm, and particularly preferably 0.3 to 1 μm.

Composite plating film 4 in which the fluororesin particles 3 are uniformly dispersed and co-deposited in the nickel matrix 2.
Can be formed by an ordinary composite plating method in which the fluororesin particles 3 are dispersed in a plating solution and plating is performed while stirring. The thickness of this composite plating film 4 is
Although not particularly limited, it is 2 to 20 μm, especially 5
The thickness is preferably 10 μm. The amount of the eutectoid fluororesin particles 3 is not particularly limited,
5 to 40% by volume, especially 25 to 30% by volume is preferable, and if it is less than 5% by volume, the fluororesin layer 5 to be described later will be described.
The adhesion between and may decrease, while 40% by volume
If it exceeds, the composite plating film 4 having sufficient strength may not be obtained.

As the fluororesin layer 5 formed on the composite plating film 4, polytetrafluoroethylene (P
TFE), tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer (PFA), tetrafluoroethylene-hexafluoropropylene copolymer (FE
P) and the like. In this case, the composite plating film 4
It is preferable to use the same fluororesin as the fluororesin particles 3 co-deposited in the composite plating film 4 in order to obtain good adhesion between the two and the above. For example, different kinds of fluororesins may be used. The thickness of the fluororesin layer 4 is not particularly limited, but is preferably 2 to 100 μm, particularly preferably 5 to 50 μm, and when it is less than 2 μm, sufficient releasability cannot be obtained. On the other hand, if the thickness exceeds 100 μm, the precision of the mold may decrease.

The fluororesin layer 5 is formed by applying the fluororesin onto the composite plating film 4 by an appropriate method such as a spraying method or a brush coating method, and then heat-treating and baking it. . In this case, the above-mentioned fluororesin can be dissolved in an appropriate solvent as necessary and applied on the composite plating film 4. The heat treatment temperature is the same as that of the fluororesin and the composite plating film 4 used.
Depending on the kind of the fluororesin particles 3 co-deposited therein, the temperature is set to a temperature at which these are melted and compatible with each other, and usually 3
It is set to 30 to 390 ° C, particularly 340 to 350 ° C.

The mold of the present invention exhibits good releasing property due to the fluororesin layer 5, and the fluororesin layer 5 is also provided.
Is firmly adhered to the composite plating film 4 by the heat treatment, and is not easily peeled off even if molding and releasing are repeated, and good releasability can be maintained for a long time. It is a thing.

That is, on the surface of the composite plating film 4,
As shown in FIG. 2, a part of the fluororesin particles 3 is present in an exposed state, and in this exposed fluororesin particle, most of the particles are nickel as shown in FIG. 2 (B). Embedded in matrix 2, only part of film 4
There are particles 3a exposed on the surface and particles 3b in which most of the particles are exposed from the surface of the film 4. In the present invention, as shown in FIG. 2, these particles 3a, 3
The fluororesin layer 5 is applied on the composite plating film 4 having b present, and heat treatment is performed in this state. The fluororesin particles 3a and 3b and the fluororesin layer exposed on the surface of the composite plating film 4 by this heat treatment. 5 and 5 are melt-integrated and firmly bonded to each other, and as shown in FIG. 1 (B), the fluororesin layer 5 is in a state of digging into many holes formed on the surface of the composite plating film 4, and the fluororesin The layer 5 and the composite plating film 4 are firmly adhered. In particular, the particles 3 mostly embedded in the nickel matrix 2
The portion 5a which was a (see FIG. 2 (B)) bites into the composite plating film 4 in a form that does not come out of the hole, and exhibits an extremely strong anchoring effect. It effectively prevents peeling from the composite plating film 4.

As described above, the mold of the present invention has good mold releasability and can maintain this good mold releasability for a long period of time, but this mold releasability is deteriorated. Even in such a case, the mold releasability can be easily reproduced without damaging the mold base material 1. That is, in the mold of the present invention, the above-mentioned fluororesin layer 5 imparting good releasability is the fluororesin particles 3 in the nickel matrix 2.
Since it is formed on the composite plating film 4 obtained by co-depositing, the mold base material 1 is prepared by using an ordinary solvent such as a release agent for electroless nickel plating used when removing the nickel plating film. It is possible to easily peel off the fluororesin layer 5 together with the composite plating film 4 without damaging the composite plating film 4 and forming the composite plating film 4 and the fluororesin layer 5 again without deteriorating the accuracy of the mold. The mold can be easily regenerated and the mold can be regenerated.

The mold of the present invention is a mold of a type for molding an inner core ball of a golf ball or a one-piece golf ball by supplying a rubber material into the cavity and performing heat vulcanization molding. A mold of a type in which an inner core sphere is placed and a thermoplastic resin such as an ionomer resin is injected and supplied into the cavity to inject a cover onto the inner core sphere, or a thermoplastic resin molded in a half cup shape on a wound core. Any mold used in the manufacture of golf balls, such as a mold in which a cover with a material is placed in a cavity and a cover layer is molded around a wound core by heating and pressurizing. You can also

The method for producing a golf ball of the present invention is to form a one-piece golf ball, a cover of a golf ball or an inner core ball by using the mold of the present invention. The molding conditions and the like are used. Known conditions can be adopted depending on the material and the molding method (injection molding, heat and pressure molding, etc.). .

According to the manufacturing method using the mold of the present invention, the molded one-piece golf ball, the cover of the golf ball, or the inner core ball is not adhered to the cavity of the mold, and the mold can be released with good mold releasability. Since the mold can be released from the mold, it is possible to reliably obtain a golf ball or an inner core sphere having a good surface condition, and it is possible to reliably manufacture a high quality golf ball.
In this case, even if the molded product is the inner core sphere of a golf ball,
The surface condition affects the performance and finish of the golf ball of the final product, and obtaining an inner core sphere with a good surface condition is very important for producing a high quality golf ball. Further, as described above, the mold of the present invention can obtain good mold releasability without requiring a troublesome work such as applying a mold release agent each time it is molded, and has good mold releasability. Since it can be maintained for a long period of time, it is possible to efficiently produce the above high-quality golf ball, and when the mold releasability is lowered, the mold releasability can be easily re-imparted. The mold can be regenerated and it is economically superior.

[0026]

EXAMPLES The present invention will be described more specifically by showing examples and comparative examples. A mold for molding an inner core sphere of a golf ball composed of a pair of mold halves made of carbon steel was subjected to electroless plating treatment at a temperature of 88 ° C. for 60 minutes using a plating bath adjusted as follows. Thickness 10 on the mold cavity surface
μm, PTFE particle eutectoid amount of 30% by volume of Ni-P / PT
An FE composite plating film was formed.

Plating bath : PTFE particles, nickel sulfate, sodium hypophosphite, complexing agents, reaction accelerators, stabilizers, pH adjusting agents so that the PTFE particles can be dispersed and contained in the composite plating film in an amount of 30% by volume. Was adjusted according to a conventional method to obtain a composite plating bath.
The PTFE particles used had an average particle diameter of 1 μm or less.

Then, PTFE is applied on the composite plating film.
Spray the dispersion liquid and apply it.
By heat treatment at 50 ℃ for 30 minutes, thickness 20μm
The fluororesin layer of was formed.

Using this mold, a molding material having the following composition was supplied into the cavity to mold the inner core sphere of the golf ball. In this case, when the mold releasability and the mold release durability were evaluated by repeating molding and demolding continuously, the molded inner core spheres were satisfactorily demolded from the mold even after the molding and demolding were repeated 650 times. The obtained inner core spheres were also excellent in surface condition.

Composition of molding material cis polybutadiene 100 parts by weight zinc acrylate 30 〃 zinc flower 15 〃 curing agent (dicumyl peroxide) 1.5 〃

For comparison, the same evaluation was performed using a mold obtained in the same manner as above except that the fluororesin layer was not formed on the composite plating film. As a result, molding and demolding were repeated. The releasability gradually decreases, 1
At the 50th time, the surface of the inner core sphere was scratched at the time of demolding, and a good molded product could not be obtained.

[0032]

As described above, the mold for producing a golf ball of the present invention can maintain a good mold releasability for a long period of time, and a molded product having a good surface condition can be efficiently manufactured for a long period of time. It can be manufactured well and can be easily regenerated when the mold releasability is lowered without damaging the mold base material. Further, according to the golf ball manufacturing method of the present invention in which a one-piece golf ball or a cover of a golf ball or an inner core ball is molded using this mold, a high quality golf ball can be manufactured efficiently and reliably.

[Brief description of drawings]

FIG. 1 is a partially enlarged cross-sectional view showing a golf ball molding die according to an embodiment of the present invention, in which FIG.
Shows the boundary between the composite plating film and the fluororesin layer,
(B) is an enlarged view of the boundary between the composite plating film and the fluororesin layer.

FIG. 2 is a partially enlarged cross-sectional view showing a state in which a fluororesin layer is applied on a composite plating film to obtain the same mold,
(A) shows each boundary part of a metal mold | die base material, a composite plating film, and a fluororesin layer, (B) expands the boundary part of a composite plating film and a fluororesin layer further.

FIG. 3 is a partially enlarged cross-sectional view showing a boundary portion between a die base material and a composite plating film in a conventional die.

FIG. 4 is a partially enlarged cross-sectional view in which the surface of the composite plating film of the mold is further enlarged, in which (A) is an unused state,
(B) is a state after long-term use.

[Explanation of symbols]

1 Mold Base Material 2 Nickel Matrix 3 Fluororesin Particles 3a Fluororesin Particles with a Part of Particles Exposed on the Surface of Composite Plating Film 3b Most of the Particles Fluororesin Particles Exposed from the Surface of Composite Plating Film 4 Composite Plating Film 5 Fluororesin layer 5a Portion of the fluororesin layer that exerts a strong anchoring effect

Claims (2)

[Claims] 1. A pair of split molds are separably joined to each other to form a spherical cavity therein, and a molding material is supplied into the cavity to form a one-piece golf ball or an inner core ball or cover of a golf ball. In a mold for producing a golf ball to be molded, a composite plating film in which fluororesin particles are eutectoid-dispersed in a nickel matrix is formed on the cavity surface, and a fluororesin is applied on the composite plating film and heat-treated. Thus, a mold for producing a golf ball, characterized in that a fluororesin layer integrated with the exposed fluororesin particles is formed on the composite plating film. 2. A one-piece golf ball or an inner core ball of a golf ball or a cover is molded by supplying a molding material into a mold in which a pair of split molds are separably joined to each other to form a spherical cavity inside. A method of manufacturing a golf ball, wherein the mold for manufacturing a golf ball according to claim 1 is used as the mold in the method of manufacturing a golf ball.