JPH08229162A - Golf ball - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a golf ball without using a caustic stripper solution that causes problems of health, safety and environment on recycling of the golf ball and its recycling method. SOLUTION: The golf ball 10 has a core 11, a recognizable indication that is printed on the core 11 and a cover 12 that is substantially transparent and installed on the core 11. And, the cover 12 has no painting or dyestuffs substantially to make the core 11 and its indication recognizable clearly through the cover 12.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a golf ball, and more particularly to a golf ball having a clear cover.

[0002]

Golf balls generally include a core and a cover. Golf balls currently in use fall into two categories. A ball with a balata cover and a ball with a more durable and cut resistant cover.

The most cut resistant cover uses Surlyn ionomer resin, which is EI du Pont de Nemours &
Ionic copolymer available from Co.). Surlyn ionomers are olefins (typically ethylene)
Is a copolymer of α, β ethylenically unsaturated carboxylic acid (for example, methacrylic acid). Neutralization of many acid groups
By metal ions such as sodium, zinc, lithium and magnesium ions. DuPont U.S. Pat. No. 3,264,272 describes a method of making ionic copolymers and is incorporated herein by reference.

Another cut resistant material that can be used for golf ball covers is an ionic copolymer or ionomer available from Exxon under the trade name Iotek, which uses acrylic acid rather than methacrylic acid. It is the same as Surlyn ionomer except that

Conventional golf ball covers are opaque. Most covers are white, which is obtained by incorporating a white pigment such as titanium dioxide into the cover material. Colored golf balls are also commercially available and the color is obtained by incorporating a pigment or dye into the cover material.

Indications such as logotypes and numbers can be printed on the cover and one or more clearcoats can be applied on the printed cover. For example, as described in US Pat.No. 5,000,458,
The cover can be coated with a clear primer coat and a clear coat or finish coat on the outside thereof.

US Pat. No. 4,798,386 describes a ball having a white core and a transparent cover, which has a fluorescent material. FIG. 1 illustrates the indicia 18 on the core visible through the transparent cover.

Range balls used in golf driving ranges have colored stripes that are printed on the surface of the cover, or the cover is completely covered with a coating of colored paint.

When indicia such as logotypes, numbers, stripes, etc. are provided on the cover of a golf ball, this indicia will be worn or abraded when the golf ball is used. And the appearance of the golf ball is impaired.

Some of the golf balls used have their appearance improved and are recycled. Range balls in particular will be recycled to reduce the cost of buying new balls. Generally, the recycling method is
A caustic stripper solution is used that softens and decomposes the urethane clear coat on the balls. This stripper solution presents health and safety issues when in use. Disposal of this solution will also lead to environmental problems. It is desired to recycle golf balls without using this stripper solution.

[0011]

SUMMARY OF THE INVENTION The present invention provides a golf ball having a clear transparent cover. The cover is preferably substantially free of pigments or dyes so that the cover is substantially clear or transparent. The core of the ball is printed with desired indicia such as logotypes, numbers and / or stripes. Alternatively or additionally, the core may be provided with a color by introducing pigments or dyes into the core or by covering the core with a colored coating. If desired, one or more clear coats can be applied to the cover.

The core and the print of the core are clearly visible through the cover. The cover protects the core and the print, which is clearly visible even after the cover has been severely worn or abraded.

The printing and / or color of the core is protected by the cover so that the balls can be stripped of the outer coating and recycled without the need to reprint on the cover. The used balls are recycled, for example in a rotor tab by rubbing the balls with a stone material to remove slight scratches, abrasions, debris, etc. The balls are then dried and recoated with one or more topcoats. The balls may be recycled multiple times if desired. This process is not currently used, and for the most part is new, developed by the present inventors.

Next, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a cross-sectional view of a golf ball formed according to the present invention. FIG. 2 is a diagram illustrating a core having a logotype and numbers before the cover is applied. FIG. 3 is a diagram for explaining the core of the range ball before the cover is applied. FIG. 4 is a diagram showing the light transmittance of various cover materials.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to FIG. 1, a golf ball 10 has a core 11 and a cover 12. The cover is coated with a transparent primer coat 13 and an outermost clear or finish coat 14.
The core 11 is preferably a solid, molded core. The core may include pigments or dyes to provide color, or the core may be covered with a paint layer or other pigmented coating. The white core is obtained by introducing titanium dioxide into the core. For example, a yellow colored core is obtained by introducing a yellow pigment into the core.

The core 16 shown in FIG. 2 is a logotype 1
7 and the identification number 18 are printed. The core can be a conventional core for solid or two-piece golf balls or a conventional core for range balls. The logotype and number can be printed on the core in the same way as it is used for printing golf ball covers.

The core 19 shown in FIG. 3 is intended for use as a range ball. Stripes 20 are printed or painted on the core. Logotype 2
Ads such as one or a company name can also be printed on the core.

The cover 12 is preferably formed of an ionomer resin such as Surlyn or Iotek resin. The cover can be injection molded around the core or can be formed by compression molding two hemispherical shells around the core. Suitable dimples are provided on the cover during compression molding or direct injection molding operations.

One or more clear coats can be applied to the cover. The primer coat 13, as described, for example, in US Pat. No. 5,000,458,
It can be a waterborne epoxy / acrylic / urethane resin system and can include a fluorescent whitening agent. In addition, the primer coat can be solvent-based, with or without a brightening agent.
Furthermore, the primer coat can be a UV curable coating system. Specific fluorescent whitening agents are described in the patent.

The outermost layer, clear coat 14, is disclosed in US Pat.
It can consist of a solvent two-component urethane paint as described in 5,000,458. The outermost clear coat 14 can be a dispersible resin system or a UV curable system.

The color of the core, the logotype on the core, the identification number, the stripe, the advertisement, etc. are clearly visible through the transparent cover and the clear coat. The core and indicia on it are protected from abrasion and wear by the cover and remain clean and legible even after severe abrasion of the outer coating and cover.

Surlyn ionomer resins are generally clear and transparent. However, in the prior art, it is common to make golf ball covers from blends of io-onomer resins neutralized with various metal cations. For example, blends of two or more ionomers selected from sodium ionomers, zinc ionomers and lithium ionomers have been used. However, we have found that if more than one ionomer resin is selected to provide the optimal relationship of resilience, distance or durability, the blend of resins will often be cloudy,
I found that it was not visually transparent. In order to maximize the transparency of the ionomer resin blend, it is advantageous to use multiple resins having substantially the same or the same proportion of acid content. U.S. Pat.No. 3,264,272
The proportion of carboxylic acid in the copolymer can vary, as described in the specification.

We have, for example, zinc Surlyn 991.
A 75/25 blend of 0 and sodium Surlyn 8527 was found to be opalescent, rather than a clear cover. The ratio 75/25 here refers to a blend of 75% Surlyn 9910 and 25% Surlyn 8527, the percentages being based on total polymer content. Zinc Surlyn 9910 has an acid content of 15% and Sodium Surlyn 8527 has an acid content of 10%.

The preferred cover blend is a blend of 75% Surlyn 9520 and 25% Surlyn 8527. Surlyn 9520 is zinc Surlyn and Surlyn 8527 is sodium Surlyn. Both surlyns have an acid content of 10%. However, other blending ratios, other Surlyns, other acid contents can also be used, for example an acid content of 15% or 20%.

The cover is preferably substantially clear or transparent. Clarity or transparency of the cover material is defined by the amount of light that passes through the cover material.

The following cover compositions were prepared for measuring and comparing light transmission. The unit is parts by weight.

[0027]

[Table 1] Ingredients EXG45-1 EXG45-11 EXG45-12 EXG45-13 ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ ━ Surlyn 8527 25.00 25.00 18.75 12.50 Surlyn 9520 75.00 75.00 56.25 37.50 Concentrate # 37302-R1 − 8.00 8.00 8.00 Concentrate # 7554-A1 − − 25.00 50.00 ━━━━━━━━━━━━━━━━━━━ ━━━━━━━━━━━━━━━━━ Total 100.00 108.00 108.00 108.00

The above two concentrates were obtained from Americhem, 2038, Main Street, Cuyohoga Falls, Ohio, USA. We do not know the exact composition of this concentrate, but concentrate # 37302-R1
Is a UV stabilizer package, which improves color aging and prevents yellowing or discoloration caused by UV rays and the like. Concentrate # 37302-R1 uses Surlyn 8940 as the base carrier resin, which is HALS (Hindered Amine Light Stabilizer).
And are commonly referred to in the industry as antioxidants. Surlyn 8940 is sodium Surlyn.

The present inventors believe that cover composition EXG45-11 is a preferred cover composition because it contains HALS and an antioxidant.

Concentrate # 7554-A1 is a concentrate containing barium sulphate and is included in EXG45-12 and EXG45-13 to explain the haze effect, with barium sulphate reducing the light transmission. Increasing the amount of barium sulphate also increases the opacity of the cover.

FIG. 4 illustrates the light transmission through the plaques of the four cover compositions. Each plaque is about 0.
It has a thickness of 125 inches (0.31 cm). 400 ~
The wavelength range of 700 nm is approximately the wavelength range of visible light.

The EXG45-1 plaque transmitted about 82% of light at 400 nm, 87% or more of light at 550 nm, and about 90% of light at 700 nm. EXG4 with UV stabilizer
5-11 did not significantly reduce the light transmission. Its light transmission is more than 80% of light at 400 nm, 55
It was about 87% at 0 nm and about 89.5% at 700 nm.

The light transmittance of EXG45-12 is 400n.
It was similar to EXG45-11 at m and 700 nm, but was less than 85% at 550 nm. EXG
45-12 materials are EXG45-1 and EXG45-
It was noticeably cloudier than 11.

The cover material, which is 0.125 inches (0.31 cm) thick, preferably has a light transmission of at least about 79% over the entire visible range of 400 to 700 nm. More preferably at least about 79 at 400 nm.
%, At least about 85% transmission at 550-700 nm. Optimally, it has greater than 85% light transmission at 550-700 nm. Unless otherwise stated, the term "substantially transparent" in the present description and claims refers to the above-mentioned light-transmissive material for plaques having a thickness of 0.125 inches (0.31 cm). I shall.

The cover is a brightening agent, an ultraviolet absorber, and H
It may include ALS, antioxidants, ultramarine and other conventional components of golf ball covers. However, the cover is substantially free of TiO ₂ or other content or dye that adversely affects its visual clarity. As used herein, the term "substantially absent" means the absence of an amount of pigment or dye that causes the light transmission of the cover to be less than the above lower limit.

Matching the flexibility of the core and cover is important for developing optimal properties. Initial tests of the above cover blends showed that a 1.520 inch (3.86 cm) diameter core was the desired size for maximum ball durability under normal and frozen atmospheres. For 1.520 inch (3.86 cm) diameter core, the cover is 0.080 inch (0.20 cm)
The ball diameter is 1.680 inches, which is the smallest diameter recognized by the USGA (American Golf Association). However, the range ball is USGA
Other diameters of the core and other thicknesses of the cover can also be used and the outer diameter of the ball can also be greater than or less than 1.680 inches, as not controlled or controlled by.

The transparent cover can be formed of a material other than the ionomer resin. For example, polyethylene, polypropylene, a specific thermoplastic elastomer, EVA or the like can be used.

The two-piece golf ball manufacturing method according to the present invention can be compared with the following conventional methods.

[0039]

[Table 2] Conventional process-two-piece ball 1. Mix the rubber compound of the core. 2. The core composition is ground and preformed into a slag. 3. Mold the core. 4. Centerlessly grind the core to the desired size. 5. Injection mold a Surlyn cover around the core. 6. Buff the ball. 7. Vibrate the ball and finish. 8. Apply primer paint. 9. Apply print logotype. 10. Apply a transparent top coat. 11. Apply top coat # 2. 12. Inspect and package.

New Process for Manufacturing Clear Cover-Two Piece Golf Ball 1. The core rubber compound (colored or uncolored) is mixed. 2. The core composition is ground and preformed into a slag. 3. Mold the core. 4. Centerlessly grind the core to the desired size. 5a. For colored cores, print directly on the core (can be single or multiple color logotypes). 5b. For uncolored cores, apply pigment paint to the core (which may include color enhancers such as pigments, dyes, aluminum flakes, pearl essences, brighteners, organic or inorganic colorants, etc.) . 6. For unpigmented / pigmented cores, pad print on primed surface. 7. Injection or compression molding Surlyn cover. 8. Buff the ball. 9. Vibrate the ball and finish. 10. Apply primer paint. Note) The primer / finish topcoat process can be automated considering the current automation of the painting process. Currently, the balls have to be manually loaded onto the paint spindle to prevent ink transfer between the balls. 11. Apply clear top coat. 12. Inspect and package.

In the golf ball manufactured according to the present invention, the color of the core and the display of the core are protected by the cover. Therefore, the used golf balls are easily recycled by an economical and environmental method without removing the primer coat and the finish coat from the cover. Simply applying a new topcoat will result in smooth wear and abrasion of the topcoat and cover. The recycled balls have a good, almost new look and have very good visibility of the core and the markings on the core. Any major defects or core / cover damage are visible and can be removed.

The recycling process according to the present invention and the conventional recycling process will be compared as follows.

Conventional recycle process balls must be thoroughly cleaned and dried. The balls are then placed in a caustic stripper solution. The urethane coating sprayed on the balls used there softens and decomposes. This urethane coating is used to protect the ball from wear and abrasion and to protect the logotype stamp on the ball.

The stripper solution is sodium hydroxide,
It is a mixture of xylol, methanol and 2-butoxyethanol. This solution causes fire and health problems if not used correctly and carefully. Vapor and / or skin contact can cause acute and chronic dermatitis and respiratory burns or irritation. Also, its disposal causes environmental problems.

The balls must be vibrated, rinsed thoroughly, brushed and freed of the softened coating material. The ball is then rotostone process and the entire coating and logotype process, namely primer coating, drying, logo stamping,
A dry topcoat (1), a topcoat (2) is applied (which likewise has a negative effect on the Surlyn cover).

The recycled process balls of the present invention are cleaned of significant debris in a commercial ball washer and then placed in a rotating tub that vibrates the balls through a stone medium. This process removes slight abrasions, wear, debris, etc. The balls are then dried and only the topcoat is coated. The balls have a near-new appearance without the cost and risk of caustic stripper solutions. From an environmental standpoint, this process is highly desirable, low cost, and the finished product has better quality and appearance. The recycling process of the present invention mechanically lubricates the balls without the use of chemicals or solvent treatments.

This recycling process can be used for range balls up to about four times. This allows
The service life of the balls can be substantially increased in a safe and economical manner.

After two or three recycling processes, a reshaping process can be introduced to reshape the ball dimples and establish the maximum flight distance of the ball.

Providing logotype stamps, markings and / or rangeball patterns on the core rather than on the cover removes the pattern illegally from the ball,
It reduces the possibility of replacing unauthorized patterns there.

While particular embodiments of the present invention have been described in detail above, this is for the purpose of illustration and many modifications thereof may be made by those skilled in the art without departing from the spirit and scope of the invention. You can see what you can do.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a golf ball formed according to the present invention.

FIG. 2 is a diagram illustrating a core having a logotype and numbers before the cover is applied.

FIG. 3 is a view for explaining the core of the range ball before the cover is applied.

FIG. 4 is a diagram showing the light transmission of various cover materials.

[Explanation of symbols]

 10 golf ball 11,16,19 core 12 cover 13 primer coat 14 clear coat 20 stripes

Claims (33)

[Claims] 1. A core and a visible indicia printed on the core and a substantially transparent cover provided on the core, the cover revealing the core and indicia through the cover. A golf ball characterized in that it is substantially free of pigments or dyes. 2. The golf ball of claim 1, wherein the core comprises a pigment that provides the core with a color visible through the cover. 3. The golf ball of claim 1, wherein the core is coated with a paint containing a pigment and the indicia is printed on the paint. 4. The core has a diameter of about 1.520 inches (3.
The golf ball according to claim 1, having a size of 86 cm). 5. The ball has a diameter of about 1.68 inches (4.
27 cm). 6. The golf ball of claim 1, wherein the cover is a blend of sodium ionomer and zinc ionomer, with the acid content of each ionomer having substantially the same proportion. 7. The golf ball of claim 1, wherein the cover is a blend of 75% zinc ionomer having an acid content of 10% and 25% sodium ionomer having an acid content of 10%. 8. The golf ball of claim 1, including at least one transparent topcoat on the cover. 9. The golf ball of claim 1, wherein the cover is a blend of ionomers having two different metal cations, each ionomer having an acid content of 15%. 10. The golf ball of claim 1, wherein the 0.125 inch (0.32 cm) thick cover has a light transmission of at least about 79% at a wavelength of 400 to 700 nm. 11. The golf ball of claim 9, wherein the light transmission is at least about 85% at a wavelength of 400-700 nm. 12. A core having a colored pigment, and a substantially transparent cover provided on the core, the cover allowing the colored core to be clearly visible through the core. , A golf ball characterized by being substantially free of pigments or dyes. 13. The golf ball of claim 12, wherein the core diameter is about 1.520 inches (3.86 cm). 14. The golf ball of claim 13, wherein the ball has a diameter of about 1.68 inches. 15. The cover is a blend of sodium ionomer and zinc ionomer, and the acid content of each ionomer has substantially the same proportion.
The golf ball described in. 16. The golf ball of claim 12, wherein the cover is a blend of 75% zinc ionomer having an acid content of 10% and 25% sodium ionomer having an acid content of 10%. 17. The golf ball of claim 12, including at least one transparent topcoat on the cover. 18. The golf ball of claim 12, wherein the cover is a blend of ionomers having two different metal cations, each ionomer having an acid content of 20%. 19. The golf ball of claim 12, wherein the 0.125 inch (0.32 cm) thick cover has a light transmission of at least 79% at a wavelength of 400 to 700 nm. 20. The golf ball of claim 12, wherein the light transmission is at least about 85% at a wavelength of 400-700 nm. 21. A core having a coating of pigmented paint and a substantially transparent cover provided on the core, the cover clearly showing the pigmented core through the cover. Thus, a golf ball that is substantially free of pigments or dyes. 22. The golf ball of claim 21, wherein the core diameter is about 1.520 inches (3.86 cm). 23. The golf ball of claim 22, wherein the diameter of the ball is about 1.68 inches (4.27 cm). 24. The cover is a blend of sodium ionomer and zinc ionomer, and the acid content of each ionomer has substantially the same proportion.
The golf ball described in. 25. The golf ball of claim 21, wherein the cover is a blend of 75% zinc ionomer having an acid content of 10% and 25% sodium ionomer having an acid content of 10%. 26. The golf ball of claim 21, including at least one transparent topcoat on the cover. 27. The golf ball of claim 21, wherein the cover is a blend of ionomers having two different metal cations, each ionomer having an acid content of 15%. 28. The golf ball of claim 21, wherein the cover is a blend of ionomers having two different metal cations, each ionomer having an acid content of 20%. 29. The golf ball of claim 21, wherein the 0.125 inch (0.32 cm) thick cover has a light transmission of at least 79% at a wavelength of 400 to 700 nm. 30. The golf ball of claim 21, wherein the light transmission is at least about 85% at a wavelength of 400-700 nm. 31. A method of recycling a used golf ball having a core, a cover and at least one transparent topcoat on the cover, the method comprising: the use of a solvent to remove the outer surface of the golf ball. A method of recycling a golf ball comprising mechanically smoothing wear and abrasion and providing a new clear topcoat on the outer surface of the golf ball. 32. a) forming a core having indicia or color on its surface; and b) being substantially transparent on said core so that the indicia or color on the surface of said core is clearly visible through the cover. A method of forming and recycling golf balls, the method comprising the steps of: c) forming a transparent cover, and c) mechanically smoothing wear and abrasion on the outer surface of the golf ball without using a solvent after using the golf ball. 33. After the cover is formed on the core, a transparent topcoat is applied to the outer surface of the cover to smooth out abrasion and wear of the outer surface of the golf ball, and then the outer surface of the golf ball. 33. The method of claim 32, wherein a new clear topcoat is applied to.