GOLF BALL HAVING MATTE SURFACE WITH IMPROVED VISIBILITY

Abstract

Provided is a golf ball having a matte surface with improved visibility. Since the golf ball has a matte surface in comparison with a golf ball having a glossy surface of the related art, the golf ball has an advantage of preventing the golfer from being dazzled caused by reflection of a dimple surface. Since the golf ball has a relatively high luminance value in comparison with a golf ball having a matte surface of the related art, the golf ball has an advantage of being seen to be larger. Since the amount of light remaining in a dimple cover is increased, fluorescent characteristics of a fluorescent material is improved, so that beautiful colors and improved visibility can be achieved. Therefore, it is possible to improve golfers' performance.

Claims

1. A golf ball comprising: a core; a white inner cover configured to cover the core; and a transmissive dimple cover configured to cover the inner cover, wherein the transmissive dimple cover is coated with a matte coating layer containing a matting agent, so that an amount of remaining light in the transmissive dimple cover is 5 to 30% or more.

2. The golf ball according to claim 1, wherein the core is configured to include one inner core or one inner core and at least one inner cover layer substantially surrounding the inner core.

3. The golf ball according to claim 1, wherein the white inner cover contains, as a material for realizing white, any one or a mixture of two or more selected from a group including titanium oxide (TiO.sub.2), zinc oxide (ZnO), zirconia (ZrO.sub.2), white lead, and barium sulfate (BaSO.sub.4).

4. A golf ball comprising: a white core; and a transmissive dimple cover configured to cover the white core, wherein the transmissive dimple cover is coated with a matte coating layer containing a matting agent.

5. The golf ball according to claim 4, wherein the white core is one inner core or a core configured with one inner core and at least one or more outer core layer substantially surrounding the inner core, and an outermost core or core layer is white.

6. The golf ball according to claim 4, wherein the white core contains, as a material for realizing white, any one or a mixture of two or more selected from a group including titanium oxide (TiO.sub.2), zinc oxide (ZnO), zirconia (ZrO.sub.2), white lead, and barium sulfate (BaSO.sub.4).

7. The golf ball according to claim 1, wherein the transmissive dimple cover is manufactured by mixing 0.03 to 3 parts by weight of a fluorescent material with respect to 100 parts by weight of a polymer resin.

8. The golf ball according to claim 2, wherein the transmissive dimple cover is manufactured by mixing 0.03 to 3 parts by weight of a fluorescent material with respect to 100 parts by weight of a polymer resin.

9. The golf ball according to claim 3, wherein the transmissive dimple cover is manufactured by mixing 0.03 to 3 parts by weight of a fluorescent material with respect to 100 parts by weight of a polymer resin.

10. The golf ball according to claim 4, wherein the transmissive dimple cover is manufactured by mixing 0.03 to 3 parts by weight of a fluorescent material with respect to 100 parts by weight of a polymer resin.

11. The golf ball according to claim 7, wherein the polymer resin is any one or a mixture of two or more selected from a group including an ionomer resin, a thermoplastic resin, a thermoplastic rubber, and a polyurethane resin.

12. The golf ball according to claim 7, wherein the fluorescent material is any one or a mixture of two or more selected from a group including a perylene-based compound, a naphthalimide-based compound, a coumarin-based compound, a xanthene-based compound, a naphtholactam-based compound, an azlactone-based compound, and an oxazine-based compound.

13. The golf ball according to claim 1, wherein the matte coating layer is manufactured by mixing 10 to 50 parts by weight of a curing agent and 1 to 30 parts by weight of a matting agent with respect to 100 parts by weight of the polyurethane paint.

14. The golf ball according to claim 2, wherein the matte coating layer is manufactured by mixing 10 to 50 parts by weight of a curing agent and 1 to 30 parts by weight of a matting agent with respect to 100 parts by weight of the polyurethane paint.

15. The golf ball according to claim 3, wherein the matte coating layer is manufactured by mixing 10 to 50 parts by weight of a curing agent and 1 to 30 parts by weight of a matting agent with respect to 100 parts by weight of the polyurethane paint.

16. The golf ball according to claim 4, wherein the matte coating layer is manufactured by mixing 10 to 50 parts by weight of a curing agent and 1 to 30 parts by weight of a matting agent with respect to 100 parts by weight of the polyurethane paint.

17. The golf ball according to claim 13, wherein the matting agent is any one or a mixture of two or more selected from a group including amorphous silica, fumed silica, silica gel, alumina, titania, zirconia, zircon, tin oxide, magnesia, polypropylene, polyethylene, polytetrafluoroethylene, Al-stearate, Zn-stearate, Ca-stearate, or Mg-stearate, finely divided polypropylene wax, and urea-formaldehyde condensate.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0031] FIG. 1 illustrates a structure of a matte coating layer including a white inner cover or a white core, a transmissive dimple cover, and a matting agent and a path of light through which irradiated light is transmitted; and

[0032] FIG. 2 illustrates a golf ball according to the present invention.

DETAILED DESCRIPTION

[0033] According to one embodiment of the present invention, there is provided a golf ball including: a core; a white inner cover configured to cover the core; and a transmissive dimple cover configured to cover the inner cover, wherein the transmissive dimple cover is coated with a matte coating layer containing a matting agent.

[0034] The core plays a key role in determining the fly distance of the golf ball by causing a strong elasticity when the golf ball is hit by a golf club. The core may be manufactured by using cis-1, 4-polybutadiene rubber as a main component, an , -ethylene unsaturated carboxylic acid or metal salt thereof for inducing crosslinking of the main component, a filler, and an additive. As a rubber for manufacturing the core may be used together with a rubber-like material other than the cis-1, 4-polybutadiene rubber.

[0035] In the above embodiment, the core is one inner core or a core configured with one inner core and at least one or more outer core layer substantially surrounding the inner core. The inner core denotes the innermost core of the golf ball, and the outer core denotes a single-layered or multi-layered core layer substantially surrounding the inner core. The core may have a two-layered core structure configured to include one outer core layer surrounding the inner core or may have a three-layered core structure configured to include a first outer core layer surrounding the inner core and a second outer core layer surrounding the first outer core layer. A multi-layered core structure having more outer core layer than those of the three-layered core structure may be used. However, an appropriate core structure is determined in consideration of the overall performance of the golf ball, the repulsive force, and the feeling of hitting.

[0036] The inner cover denotes a separate cover which is in contact with the inside of the outermost cover and substantially surrounds the core and may be configured as a single layer or a multiple layer.

[0037] The inner cover may be manufactured using a material having a lower resilience than a material used for the core and a stronger physical property than the core. The material of the inner cover may be any one or a mixture of two or more selected among polymer resins such as an ionomer resin, a polyester resin, a polyether ester copolymer, a polyurethane resin, a polyamide resin, and a thermoplastic rubber. A dimple cover is provided on the outside of the inner cover. When the dimple cover has a transparent property and implements a hue while containing a fluorescent material, it is preferable that the inner cover is white. When the color of the inner cover is white, a portion of the light irradiated on the golf ball primarily causes irregular reflection with the fluorescent material of the dimple cover, and after the remaining light is transmitted through the dimple cover to reach the white inner cover, the remaining light is secondarily reflected in the reverse direction to cause irregular reflection with the fluorescent material of the dimple cover. Therefore, the fluorescence characteristics of the dimple cover are greatly increased, so that the luminance of the golf ball is improved. As the luminance of the golf ball is increased as described above, the golf ball is seen to be larger in size, and thus, golfers can improve mental concentration to the golf ball and improve the performance.

[0038] In the above embodiment, the inner cover of the present invention is white. Preferably, the white of the inner cover is white represented by HSB coordinate (0, 0, 100).

[0039] In the above embodiment, with respect to the white inner cover, any one or a mixture of two or more selected from a group including titanium oxide (TiO.sub.2), zinc oxide (ZnO), zirconia (ZrO.sub.2), white lead, and barium sulfate (BaSO.sub.4) is used as a material for realizing the white. Preferably, with respect to the white inner cover, titanium oxide (TiO.sub.2) is used as a material for realizing the white.

[0040] The dimple cover is a cover which is the outermost cover of a golf ball and includes a dimple that aerodynamically obtains a lift force and improves flight characteristics.

[0041] In the above embodiment, the transmissive dimple cover of the present invention is manufactured by mixing 0.03 to 3 parts by weight of a fluorescent material with respect to 100 parts by weight of a polymer resin. Preferably, the transmissive dimple cover of the present invention is manufactured by mixing 0.05 to 2 parts by weight of a fluorescent material with respect to 100 parts by weight of a polymer resin. More preferably, the transmissive dimple cover of the present invention is manufactured by mixing 1 part by weight of a fluorescent material with respect to 100 parts by weight of a polymer resin.

[0042] When an amount of less than 0.03 parts by weight of the fluorescent material is used, irregular reflection on the fluorescent material is insignificant and, thus, the fluorescence characteristics are lowered. When an amount of more than 3 parts by weight of the fluorescent material is added, the amount of light transmitted through the dimple cover and reaching the inner cover is reduced, so that the fluorescence characteristics are rather lowered.

[0043] In the above embodiment, as a main component of the dimple cover, one or more mixtures selected from a group of polymer resins including an ionomer resin, a thermoplastic resin, a thermoplastic rubber, and a polyurethane resin may be used. Preferably, the main component of the dimple cover is an ionomer resin. The ionomer resin is strong and elastic, and in particular, the ionomer resin is transparent. Therefore, the ionomer resin has a higher light transmittance than other polymer resins, and thus, the ionomer resin is preferable as the main component of the dimple cover of the present invention.

[0044] The visibility of the golf ball denotes a degree to which the presence of the golf ball or the shape and color of the golf ball are identified relative to the field grass when the golf ball is located at a distance in sunlight or under illumination lamps in the field. In light, red is classified as long wavelength, and violet is classified as short wavelength. The wavelengths in red and violet ranges are different, and the different wavelengths are seen in different colors. Among the colors, colors that are felt warm have long wavelengths and high transmittance. On the other hand, the colors that are felt cold have short wavelengths and are easily scattered by particles such as moisture in the air. Most of fluorescent materials which may be used in the present invention emit warm colors, and thus, if the fluorescent material is used as a material for a golf ball cover, there is an advantage that the light is more strongly reflected in sunlight or under illumination lamps and the visibility is improved.

[0045] The fluorescent material contained in the dimple cover of the present invention may be any one or a mixture of two or more selected from a group including a perylene-based compound, a naphthalimide-based compound, a coumarin-based compound, a xanthene-based compound, a naphtholactam-based compound, an azlactone-based compound, and an oxazine-based compound. In addition, an insoluble fluorescent material manufactured through chain extension reaction between one selected from the above-described group of fluorescent dyes and organic or inorganic compound may be used. A phosphorescent pigment made of strontium aluminate as a main component may be used. A fluorescent material manufactured through mixing or partial polymerization between one selected from the above-described group of fluorescent dyes and any one or a mixture of two or more selected from a group of binder resins including an acrylic resin, a urethane resin, a vinyl chloride resin, and a polyesteramide and pulverization may be used. Preferably, the fluorescent dye is a perylene-based compound or a naphtalimide compound. More preferably, the fluorescent dye is a naphthalimide-based compound. Since the naphthalimide-based compound is excellent in saturation of the fluorescent material, the naphthalimide-based compound may be preferably used for the golf ball according to the present invention to improve the luminance.

[0046] The matte coating layer has a matting property and has a function of protecting the dimple cover by covering the dimple cover. The matting property of the matte coating layer is realized by a matting agent that induces irregular reflection of the light irradiated on the golf ball.

[0047] In the above embodiment, the matte coating layer is manufactured by mixing 10 to 50 parts by weight of a curing agent and 1 to 30 parts by weight of a matting agent with respect to 100 parts by weight of a polyurethane paint.

[0048] Preferably, the matte coating layer is manufactured by mixing 20 to 40 parts by weight of a curing agent and 5 to 20 parts by weight of a matting agent with respect to 100 parts by weight of a polyurethane paint.

[0049] More preferably, the matte coating layer is manufactured by mixing 30 parts by weight of a curing agent and 10 parts by weight of a matting agent with respect to 100 parts by weight of a polyurethane paint. When an amount of less than 10 parts by weight of the curing agent is added, there is a disadvantage in that the curing time is long. When an amount of more than 50 parts by weight of the curing agent is added, the matting property may be lowered. When the matting agent is used in an amount of less than 1 part by weight or in an amount of more than 35 parts by weight, the capability of implementing the matte surface is lowered.

[0050] The polyurethane paint used in the present invention is preferably a two-component solution type paint including a base and a curing agent. As polyol which is the main component of the solution used in the above-mentioned main component, there is polyester, polyether, or polyester ether co-polymer. In addition, a mixed polyol in which a part of the polyol is reacted with a siloxane compound, polysilicon, or the likes may also be used as a main component. With respect to the curing agent according to the present invention, polyisocyanate may be as a main component. The isocyanate used in the polyisocyanate may be any one or a mixture of two or more selected from a group including TDI, MDI, HMDI, XDI, and IPDI. The above-mentioned main component and curing agent are mixed at an appropriate ratio and applied on the dimple cover layer. As a diluting solvent for appropriate mixing, any one or a mixture of two or more selected from a group including MEK, MIBK, IPA, and toluene may be used.

[0051] According to another embodiment of the present invention, the matting agent is any one or a mixture of two or more selected from a group including amorphous silica, fumed silica, silica gel, alumina, titania, zirconia, zircon, tin oxide, magnesia, polypropylene, polyethylene, polytetrafluoroethylene, Al-stearate, Zn-stearate, Ca-stearate, or Mg-stearate, finely divided polypropylene wax, and urea-formaldehyde condensate. Preferably, the matting agent is amorphous silica, fumed silica or silica gel.

[0052] The silica-based matting agent has various particle sizes of silica crystals and is excellent in irregular reflection characteristics with respect to light, so that the silica-based matting agent irregularly reflects the light which is reflected on the white inner cover to proceed to the outside of the golf ball, and thus, in comparison with other matting agents, there is an advantage in that the light to be allowed to remain in the dimple cover.

[0053] According to another embodiment of the present invention, provided is a golf ball including a white core and a transmissive dimple cover configured to cover the white core, wherein the transmissive dimple cover is coated with a matte coating layer containing a matting agent.

[0054] According to one embodiment of the present invention, the white core is one inner core or a core configured with one inner core and at least one or more outer core layer substantially surrounding the inner core, and an outermost core layer is white.

[0055] The core, the transmissive dimple cover, and the matte coating layer are described in detail in the above-described embodiment of the present invention, and thus, the description thereof will be omitted in order to avoid redundant description in the specification.

[0056] According to one embodiment of the present invention, in the white core, one or two or more mixtures selected from a group including titanium oxide (TiO.sub.2), zinc oxide (ZnO), zirconia (ZrO.sub.2), white lead, and barium sulfate (BaSO.sub.4) is used as a material for realizing white. Preferably, in the white core, titanium oxide (TiO.sub.2) is used as a material for realizing white.

[0057] The golf balls according to one aspect and another aspect of the present invention are in common in that a white layer (a white core or inner cover of the above-described one aspect and a white core of the above-described another aspect) exists in a lower layer and a dimple cover where a matte coating layer exists is included in an upper layer. The matte coating layer contains a matting agent, and the dimple cover contains a fluorescent material.

[0058] In the golf ball according to the present invention, dazzling caused by the reflection on the glossy coating layer and the irregular reflection on the uneven shape of the dimple is removed by the following steps, and in comparison with a golf ball in the related art having a nontransparent dimple cover on a glossy surface, the luminance is improved (refer to FIG. 1).

Step 1: Primary Irregular Reflection Step by Matting Agent of Matte Coating Layer

[0059] First, the light irradiated on the golf ball according to the present invention is transmitted through the matte coating layer and is irregularly reflected by the matting agent, so that the amount of reflected light that causes dazzling is reduced. In addition, since the irregularly reflected light is excluded, the residual light enters the inside of the dimple cover.

Step 2: Primary Scattering Step with Fluorescent Material of Dimple Cover

[0060] A portion of the light entering the inside of the dimple cover collides with the fluorescent material to cause primary scattering to develop the fluorescence characteristics of the golf ball, and the remaining light is transmitted through the dimple cover and reaches the white layer.

Step 3: Reflection on White Layer and Secondary Scattering with Fluorescent Material of Dimple Cover

[0061] A portion of the light reaching the white layer is mostly reflected and proceeds to the outside of the golf ball. At this time, a portion of the light collides with the fluorescent material in the dimple cover to cause secondary scattering, and thus, the fluorescence characteristics are greatly increased. And the remaining light is transmitted through the dimple cover to reach the matte coating layer.

Step 4: Second Irregular Reflection Step by Matting Agent of Matte Coating Layer

[0062] A portion of the light that has reached the matte coating layer is transmitted through the matte coating layer and proceeds to the outside of the golf ball. The remaining light is secondarily irregularly reflected by the matting agent to enter the dimple cover layer again.

Step 5: Step of Forming Light Scattering Loop

[0063] The light entering the dimple cover collides with the fluorescent material of the dimple cover again to cause tertiary scattering or reach the white layer, and after that, the scattered light is reflected, and steps 3 and 4 are repeated. This is a light scattering loop.

[0064] As a result, in the golf ball according to the present invention, an amount of light cannot be emitted from the golf ball but remains in the golf ball by the matting agent of the matte coating layer and the scattering loop formed by the white layer, and thus, the amount of remaining light on the dimple cover is increased. Therefore, the fluorescence characteristics of the fluorescent material are greatly improved.

[0065] According to one embodiment of the present invention, in the golf ball, since 5 to 30% of the light irradiated by the above process remains in the transmissive dimple cover, the fluorescence characteristics of the fluorescent material contained in the transmissive dimple cover are improved, and thus, the luminance is increased. Preferably, in the golf ball according to the present invention 10 to 20% of the light irradiated by the above process remains in the transmissive dimple cover.

[0066] According to another embodiment of the present invention, the golf ball has a luminance value of 30 to 35 cd/m.sup.2 measured at a distance of 3 m from a reference light source having a luminance value of 183.2 cd/m.sup.2.

[0067] According to still another embodiment of the present invention, the golf ball is seen as distinguished from the field grass at a distance of 250 m from the field.

[0068] A golf ball having a matte coating layer with a matting agent containing the above-described white core or white inner coverthe transmissive dimple cover containing a fluorescent materialmay be manufactured as a golf ball having the following configurations: (1) a two-piece golf ball configured to include a core and a cover; (2) a three-piece golf ball configured to include a core and a two-layered cover or a two-layered core and a cover; (3) a four-piece golf ball configured to include a core and a three-layered cover, a two-layered core and a two-layered cover, or a three-layered core and a cover; (4) a 5-piece golf ball configured to include a core and a four-layered cover, a two-layered core and a three-layered cover, or a three-layered core and a two-layered cover; or (5) a 6-piece golf ball configured to include a two-layered core and a four-layered cover or a three-layered core and a three-layered cover.

[0069] Advantages of the golf ball according to the present invention are summarized as follows.

[0070] When the golf ball according to the present invention is used in playing golf, reflection of sunlight is alleviated and, thus, there is no dazzling. Since the golf ball has a matte surface, the shape of the dimple is not visible, and thus, the golf ball can be seen as a complete sphere, and the luminance is high. Therefore, the golf ball is advantageously seen to have a larger size than a golf ball having a matte surface in the related art, and thus, it is possible to more precisely hit the golf ball. In addition, since the golf ball according to the present invention is configured by using a fluorescent material having a long wavelength, it is possible to identify the golf ball even at a distance of 250 m, so that it is possible for a golfer to have a time for designing a strategy for pin shooting while moving for the next shot. Therefore, the golf ball has an advantage of improving psychological stability. Accordingly, the golfer using the golf ball according to the present invention can expect the effect of improving concentration on the golf ball, psychological stability, and the performance.

Example

[0071] In general, a dimple cover of a golf ball includes a white nontransparent cover or a nontransparent cover having various colors. According to the present invention, a transparent dimple cover in which irradiated light can be transmitted to a core or an inner cover of the golf ball and the transmitted light can be reflected on the core or the inner cover and can be transmitted again, is manufactured and applied to the golf ball

Example: Matte Coating Layer-Transparent Dimple Cover-Fluorescent Golf Ball

[0072] A matte coating layer-transparent dimple cover-fluorescent golf ball according to Example is configured to include a white core or inner cover, a dimple cover manufactured on the white core or inner cover by using an ionomer and a fluorescent material, and a coating layer on the dimple cover. First, the white inner cover injected on the core was manufactured. When the color of the inner cover is white, the color applied to the dimple cover does not interfere with the other colors and is naturally expressed. Since most of the light transmitted through the dimple cover is reflected by white, it is possible to obtain an effect of allowing the reflected light to proceed to the dimple cover toward the outside of the golf ball. In the case of a golf ball having no inner cover, it is possible to obtain the same effect even if the core is formed to be white and is configured to include the dimple cover and the coating layer. The dimple cover was manufactured by adding 0.2 parts by weight of a green fluorescent material (green, 911 series, Sterling Color INC.) to 100 parts by weight of an ionomer which is a polymer resin, extruding, mixing, and, after that, injecting the resin on the inner cover. The dimple cover has a transparent characteristic by not adding TiO.sub.2 so that the light can be transmitted through the dimple cover to reach the core or the inner cover. Since the dimple cover is not added with TiO.sub.2 to have a transparent characteristic, transmission of light is not disturbed by other configurations except for the green fluorescent material contained in the dimple cover. In general, after injection or casting a dimple cover covering over a core or an inner cover by applying a two component solution type glossy polyurethane paint coating agent and curing, the durability of the golf ball is improved. In the present invention, a matte coating agent of which glossy characteristics are changed by adding a matting agent prepared in advance by dispersing well to the two component solution type glossy polyurethane paint was manufactured, and by applying the matte coating agent on the dimple cover, a matte coating layer-a transparent dimple cover-fluorescent golf ball was achieved. The matte type coating agent was manufactured by mixing 30 parts by weight of a curing agent and 10 parts by weight of amorphous silica as a matting agent with respect to 100 parts by weight of the glossy polyurethane paint.

Comparative Example 1: Glossy Coating Layer-Transparent Dimple Cover-Fluorescent Golf Ball

[0073] A glossy coating layer-transparent dimple cover-fluorescent golf ball according to Comparative Example 1 was manufactured through the same processes as those of the matte coating layer-transparent dimple cover-fluorescent golf ball according to Example except for the coating agent for manufacturing the coating layer. As the coating agent in Comparative Example 1, the same two component solution type glossy polyurethane paint as that of Example was used. A coating solution was manufactured by a method of mixing 30 parts by weight of the curing agent into 100 parts by weight of the glossy polyurethane paint described above. By coating the dimple cover with the coating solution, the glossy coating layer-transparent dimple cover-fluorescent golf ball according to Comparative Example 1 was achieved.

Comparative Example 2: Matte Coating Layer-Nontransparent Dimple Cover-Fluorescent Golf Ball

[0074] A matte coating layer-nontransparent dimple cover-fluorescent golf ball according to Comparative Example 2 was manufactured by using the same processes of those of the method of manufacturing the matte coating layer-transparent dimple cover-fluorescent golf ball according to Example except for adding TiO.sub.2 to allow the dimple cover to have non-transparence characteristic. The dimple cover of Comparative Example 2 was manufactured by adding 0.3 parts by weight of a green fluorescent material (green, 911 series, Sterling Color INC.) and 0.7 parts by weight of TiO.sub.2 to 100 parts by weight of a polymer resin (ionomer). Although the content (0.3 parts by weight) of the green fluorescent material is slightly different from the content (0.2 parts by weight) of the green fluorescent material of Example, the difference in fluorescence characteristics caused by the difference in content is insignificant. Therefore, there is no problem in comparing and analyzing a change in characteristics of the fluorescent pigment caused by the difference in transparency of the dimple cover between Example and Comparative Example 2.

Comparative Example 3: Glossy Coating Layer-Nontransparent Dimple Cover-Fluorescent Golf Ball

[0075] A glossy coating layer-nontransparent dimple cover-fluorescent golf ball according to Comparative Example 3 was manufactured through the same processes as those of the matte coating layer-nontransparent dimple cover-fluorescent golf ball according to Comparative Example 2 except for a coating agent for manufacturing a coating layer. As the coating agent in Comparative Example 3 which is a different point from Comparative Example 2, the same two component solution type glossy polyurethane paint as those of Example and Comparative Examples was used. A coating solution of Comparative Example 3 was manufactured by mixing 30 parts by weight of a curing agent into 100 parts by weight of a glossy polyurethane paint. By coating the dimple cover with the coating solution, the glossy coating layer-nontransparent dimple cover-fluorescent golf ball according to Comparative Example 3 was achieved.

Comparative Example 4: Matte Coating Layer-Transparent Dimple Cover-Nonfluorescent Golf Ball

[0076] A matte coating layer-transparent dimple cover-nonfluorescent golf ball according to Comparative Example 4 was manufactured through the same processes as those of the matte coating layer-transparent dimple cover-fluorescent golf ball according to Example except for whether or not to add a fluorescent material in the dimple cover. As a material for a dimple cover in Comparative Example 4 which is a different point from Example, 100 parts by weight of a pure polymer resin (ionomer) without adding a fluorescent material or TiO.sub.2 was used.

Comparative Example 5: Glossy Coating Layer-Transparent Dimple Cover-Nonfluorescent Golf Ball

[0077] A glossy coating layer-transparent dimple cover-nonfluorescent golf ball according to Comparative Example 5 was manufactured through the same processes as those of Comparative Example 4 except for a coating agent. As the coating agent which is a different point from Comparative Example 4, the same two component solution type glossy polyurethane paint as those of Example and Comparative Examples was used. A coating solution of Comparative Example 3 was manufactured by mixing 30 parts by weight of a curing agent into 100 parts by weight of a glossy polyurethane paint. By coating the dimple cover with the coating solution, the glossy coating layer-transparent dimple cover-nonfluorescent golf ball according to Comparative Example 5 was achieved.

[0078] The following table lists compositions in Example and Comparative Examples.

TABLE-US-00001 TABLE 1 Comparative Comparative Comparative Comparative Comparative Example Example 1 Example 2 Example 3 Example 4 Example 5 Color of Inner Cover White White White White White White Dimple Polymer Resin 100 parts 100 parts 100 parts 100 parts 100 parts 100 parts Cover (Ionomer) by weight by weight by weight by weight by weight by weight Dimple Fluorescent 0.2 parts 0.2 parts 0.3 parts 0.3 parts 0 parts 0 parts Cover Material (Green) by weight by weight by weight by weight by weight by weight Dimple TiO.sub.2 0 parts 0 parts 0.7 parts 0.7 parts 0 parts 0 parts cover by weight by weight by weight by weight by weight by weight Dimple Color of Fluorescent Fluorescent Fluorescent Fluorescent Transparent Transparent cover Dimple Cover Green Green Green Green Coating Glossy Poly- 100 parts 100 parts 100 parts 100 parts 100 parts 100 parts Layer urethane Paint by weight by weight by weight by weight by weight by weight Coating Curing Agent 30 parts 30 parts 30 parts 30 parts 30 parts 30 parts Layer by weight by weight by weight by weight by weight by weight Coating Matting Agent 10 parts 0 parts 10 parts 0 parts 10 parts 0 parts Layer by weight by weight by weight by weight by weight by weight Coating Characteristic Matte Glossy Matte Glossy Matte Glossy layer of Coating Layer

Experimental Example 1: Comparison of External Appearance of Golf Ball

[0079] As a result of observation of the external appearance of the matte coating layer-transparent dimple cover-fluorescent golf ball according to Example, it was observed that the irradiated light scattered with the green fluorescent material of the dimple cover or scattered from the inner white core or inner cover through the dimple cover. It was observed that the light transmitted through the dimple cover and reflected from the white inner core or inner cover scattered with the green fluorescent material of the dimple cover, so that the light of the green wavelength is diffused, and thus, the golf ball was observed to have a bright green fluorescent color. In addition, due to the matting property, the shapes of the dimples did not appear clear, and thus, it was observed that the shape of the golf ball was shown to have a perfect sphere. On the contrary, in the golf ball according to Comparative Example 1, due to the glossy property of the coating layer, the light was strongly reflected on the glossy coating layer, so that the luminance was strong, but the light intensity was not constant. Since the light intensity was changed according to the observation angle, it was found that there was a concern that the golfer's concentration was lowered. In addition, it was found that the green fluorescent hue of the dimple cover was also decreased by half.

[0080] As a result of observation of the matte coating layer-nontransparent dimple cover-fluorescent golf ball according to Comparative Example 2, although the coating layer is processed to be matte, due to the irregular reflection of light by the dimples of the nontransparent dimple cover, the shapes of the dimples appeared clear, and thus, it was observed that the shape of the golf ball was not shown to have a perfect sphere. In addition, although the content of the fluorescent material was also 1.5 times larger than that of Example, it was observed that the luminance was lowered. In the golf ball manufactured by processing the matte coating layer by using a glossy coating layer of Comparative Example 3, the irregular reflection caused by the dimples as well as the short comings caused by the glossy coating layer of Comparative Example 1 was observed, and the feeling of color was deteriorated. Since the light intensity was changed according to the observation angle, it was found that there was a concern that the golfer's concentration was lowered. In addition, in the golf balls according to Comparative Examples 4 and 5 manufactured by using a pure polymer resin (ionomer) not containing a fluorescent material or TiO.sub.2 in the dimple cover although injecting the dimple cover on the white inner cover like Example and Comparative Examples 2 and 3 and having different coating layers such as a glossy coating layer or a matte coating layer, it was observed that the shapes of the dimples of the dimple cover appeared clear, and thus, the irregular reflection caused by the uneven shapes of the dimples greatly occurred (refer to FIG. 2).

Experimental Example 2: Measurement of Light Transmittance and Calculation of Amount of Remaining Light

[0081] In the above-described golf balls, in order to check how much the color of the core or the inner cover is transmitted through the dimple cover and the coating layer to be projected, with respect to the dimple covers and the coating layers of the golf balls, total light transmittance was measured in accordance with ASTM D1003-13 Procedure A, and the results were compared and analyzed (refer to Table 2).

TABLE-US-00002 TABLE 2 Total Type of Color of Light Coating Dimple Transmittance of Trans- Golf Ball Layer Cover Dimple Cover mittance Example Matte Fluorescent Transmissive 22.8% Coating Green Layer Comparative Glossy Fluorescent Transmissive 23.2% Example 1 Coating Green Layer Comparative Matte Fluorescent Non-transmissive 6.9% Example 2 Coating Green Layer (including TiO.sub.2) Comparative Glossy Fluorescent Non-transmissive 7.0% Example 3 Coating Green Layer (including TiO.sub.2) Comparative Matte Transparent Transmissive 84.5% Example 4 Coating Layer Comparative Glossy Transparent Transmissive 90.5% Example 5 Coating Layer

[0082] The golf balls manufactured by applying a matte coating layer (Example) and a glossy coating layer (Comparative Example 1) on a dimple cover manufactured by mixing only 0.2 parts by weight of a fluorescent material without adding TiO.sub.2 to a polymer resin (ionomer) exhibited total light transmittance of 22.8% and 23.2%, respectively. It was found that white color of the core or the inner cover was transmitted through the dimple cover to be projected. However, the golf balls manufactured by applying a matte coating layer (Comparative Example 2) and a glossy coating layer (Comparative Example 3) on a dimple cover manufactured by adding 0.7 parts by weight of TiO.sub.2 to a polymer resin (ionomer) and mixing 0.3 parts by weight of a fluorescent material exhibited total light transmittance of 6.9% and 7.0%, respectively. It was found that white color of the core or the inner cover was not transmitted through the dimple cover so as not to be projected and most of the white color was blocked. In addition, the golf balls manufactured by applying a matte coating layer (Comparative Example 4) and a glossy coating layer (Comparative Example 5) on a dimple cover manufactured without adding both of TiO.sub.2 and a fluorescent material to a polymer resin (ionomer) exhibited total light transmittance of 84.5% and 90.5%, respectively. It was found that most colors of the core or the inner cover was projected.

[0083] As a result of observation of the outer appearance of the golf balls according to Example and Comparative Examples, it was observed that the golf ball according to Example where the matte coating layer is applied in the golf ball obtained by injecting the dimple cover mixed with only the polymer resin (ionomer) and the fluorescent material on the white core or inner cover was clearest, exhibits bright hue, and was seen to be larger. It is determined that the result is obtained because the fluorescence emission effect of the fluorescent material is stronger. The degree of the fluorescence emission effect is proportional to the amount of light scattered by the fluorescent material. Therefore, in the case where the amount of light entering the dimple cover is large or the stay time of the entering light is increased due to the light trapping phenomenon, the fluorescence emission is improved. According to the result of Table 2, it can be understood that, although total light transmittance of Comparative Examples 4 and 5 is about 4 to 5 times larger than that of Example and Comparative Example 1, due to the characteristics of the transparent dimple cover, the color of the white core or inner cover is shown toward the outside of the cover, but the sharpness thereof is lowered and the color is not clear in comparison with the nontransparent dimple cover where a fluorescent material is contained or both of the fluorescent material and TiO.sub.2 are contained. According to the result of observation of the outer appearance of actual golf balls, particularly, it was observed that the outer appearance of the golf ball according to Example was clearest, bright hue was exhibited, and the golf ball was seen to be larger. Therefore, it is determined that the above-described results of observation of the golf ball according to Example were caused by the light trapping phenomenon rather than by the amount of the entering light. In order to analyze and investigate the phenomenon, forward transmittance and reverse transmittance were measured in accordance with ASTM D1003-13 Procedure A, and the reflected and transmitted amount of forward transmitted light and the amount of remaining light were calculated (refer to Table 3). The amount of remaining light is used as a measure indicating the degree of light trapping phenomenon.

TABLE-US-00003 TABLE 3 Reflected and Transmitted Amount of Type Of Forward Reverse Forward Amount of Coating Trans- Trans- Transmitted Remaining Layer mittance mittance Light Light Example Matte 23.7% 23.2% 5.5% 18.2% Coating Layer Comparative Glossy 24.0% 24.1% 5.8% 18.2% Example 1 Coating Layer Comparative Matte 97.1% 86.3% 83.8% 13.3% Example 4 Coating Layer Comparative Glossy 90.7% 90.9% 82.4% 8.3% Example 5 Coating Layer

[0084] Table 3 lists forward transmittances, reverse transmittances, reflected and transmitted amounts of forward transmitted light, and amounts of remaining light with respect to golf balls manufactured by applying a matte coating layer (Example) a glossy coating layer (Comparative Example 1) on a dimple cover manufactured by mixing only 0.2 parts by weight of a fluorescent material without adding TiO.sub.2 to a polymer resin (ionomer) and golf balls manufactured by applying a matte coating layer (Comparative Example 4) and a glossy coating layer (Comparative Example 5) on a dimple cover manufactured by using only a polymer resin (ionomer) without adding TiO.sub.2 and a fluorescent material to the polymer resin (ionomer). The forward transmittance denotes an amount of transmitted light proceeding from the coating layer to the dimple cover and the core or the inner cover with respect to the 100% of the amount of incident light. The reverse transmittance denotes an amount of transmitted light proceeding from the core or the inner cover to the dimple cover and the coating layer with respect to 100% of the amount of incident light. The reflected and transmitted amount of forward transmitted light denotes the amount of light proceeding from the coating layer toward the dimple cover and the core or inner cover, being transmitted to reach the white core or inner cover, being reflected and transmitted to the outside in the reverse direction, and being emitted to the outside. The amount of remaining light denotes an amount of light remaining in the inside (coating layer and dimple cover) of the golf ball with respect to 100% of the amount of incident light. Therefore, the amount of remaining light can be calculated by a method of subtracting, from the amount (forward transmittance) of the light entering the inner side of the golf ball from the outside, the amount (reflected and transmitted amount of reverse transmitted light) of the light being emitted to the outside due to reflection the light entering the inner side of the golf ball from the outside on the white inner core or inner cover.

[0085] In Example and Comparative Example 1, the light emission efficiencies of the fluorescent materials contained in the dimple covers are the same, and the transmittances are compared. As a result, it was observed that, in the glossy coating layer (Comparative Example 1), the reverse transmittance is larger by 0.1% than the forward transmittance, and thus, the amount of reflected light at the time when the light proceeds in the reverse direction becomes smaller. In addition, in the matte coating layer (Example), the forward transmittance is larger by 0.5% than the reverse transmittance. Therefore, it can be understood that the amount of reflected light is larger when the light propagates in the reverse direction. However, when comparing the amounts of remaining light in Example and Comparative Example 1, even though the difference (0.1%) between the forward transmittance (24%) and the reverse transmittance (24.1%) of Comparative Example 1 is 5 times the difference of (0.5%) between the forward transmittance (23.7%) and the reverse transmittance (23.2%) of Example, it was observed that the glossy coating layer (Comparative Example 1) and the matte coating layer (Example) have the same amount of remaining light (18.2%). The result is considered to be caused by the light emission effect of the fluorescent material contained in the dimple cover of Example and Comparative Example 1. In order to observe the change in the amount of remaining light by the matte coating layer and the glossy coating layer by excluding the light emission effect of the above-described fluorescent material involved in the calculation of the amount of remaining light, with respect to Comparative Examples having difference in a matte coating layer (Comparative Example 4) and in a glossy coating layer (Comparative Example 5) without including any fluorescent material except for a polymer resin (ionomer) in the dimple cover, the amount of remaining light was calculated in the same manner as described above. As a result of the calculation, in the golf ball according to Comparative Example 5 using a glossy coating layer, it was found that the forward transmission (90.7%) was 0.2% lower than the reverse transmittance (90.9%), and thus, a more amount of light was further transmitted in the reverse direction. After that, the light was reflected on the surface of the coating layer, so that the amount of remaining light in the dimple cover (inside the golf ball) was calculated to be 8.2%. On the contrary, in the golf ball according to Comparative Example 4 using a matte coating layer, it was found that the forward transmittance (97.1%) was 10.8% higher than the reverse transmittance (86.3%), and thus, a more amount of light was further transmitted in the forward direction. After that, the light was reflected on the surface of the coating layer, so that the amount of remaining light in the dimple cover was calculated to be 13.3%.

[0086] As a result, it was found that, in the golf ball using a matte coating layer, 5.1% of light can be allowed to further remain in the dimple cover in comparison with the golf ball using a glossy coating layer. It can be understood from the above result that the use of a matte coating layer allows a more amount of light to remain in the dimple cover in comparison with the use of a glossy coating layer, so that the probability that light collides with the fluorescent material to exhibit the fluorescence effect is greatly increased, the fluorescent color is clearer, and brighter hue is exhibited. Therefore, the golf ball is seen to be larger, and thus, the golf ball has excellent visibility.

Experimental Example 3: Measurement of Light Reflectance

[0087] A golf ball containing a glossy coating layer is disadvantageous in that the performance is deteriorated due to dazzling caused by external light in the field, which deteriorates concentration and obstructs an accurate hit. In order to prevent such disadvantages, in the present invention, a matte coating agent manufactured by adding a matting agent to a polyurethane-based glossy coating paint is applied to a golf ball. The reflectance of the golf ball manufactured by using the matte coating agent was measured and compared with a golf ball to which a glossy coating agent manufactured by using only a polyurethane based coating paint was applied (refer to Table 4).

TABLE-US-00004 TABLE 4 Reflectance Reflectance Type of Coating Layer (85) (60) Example Matte Coating Layer 21 G.U 1 G.U Comparative Glossy Coating Layer 105 G.U 96 G.U Example 1 Comparative Matte Coating Layer 21 G.U 2 G.U Example 2 Comparative Glossy Coating Layer 104 G.U 96 G.U Example 3 Comparative Matte Coating Layer 26 G.U 8 G.U Example 4 Comparative Glossy Coating Layer 113 G.U 153 G.U Example 5

[0088] With respect to the golf balls manufactured by applying a glossy coating layer (Comparative Example 1) and a matte coating layer (Example) on a dimple cover manufactured by mixing only 0.2 parts by weight of a fluorescent material without adding TiO.sub.2 to a polymer resin (ionomer), the golf ball applied with the glossy coating layer exhibited a glossiness of 105 G.U at 85 or 96 G.U at 60, and the golf ball applied with the matte coating layer exhibited a glossiness of 21 G.U at 85 or 1 G.U at 60. With respect to golf balls manufactured by applying a glossy coating layer (Comparative Example 3) and a matte coating layer (Comparative Example 2) on a dimple cover manufactured by adding 0.7 parts by weight of TiO.sub.2 to a polymer resin (ionomer) and mixing 0.3 parts by weight of a fluorescent material, the golf ball applied with the glossy coating layer exhibited a glossiness of 104 G.U at 85 or 96 G.U at 60, and the golf ball applied with the matte coating layer exhibited a glossiness of 21 G.U at 85 or 2 G.U at 60. With respect to golf balls manufactured by applying a glossy coating layer (Comparative Example 5) and a matte coating layer (Comparative Example 4) on a dimple cover manufactured without adding both of TiO.sub.2 and a fluorescent material to a polymer resin (ionomer), the golf ball applied with the glossy coating layer exhibited a glossiness of 113 G.U at 85 or 153 G.U at 60, and the golf ball applied with the matte coating layer exhibited a glossiness of 26 G.U at 85 or 8 G.U at 60. As a result of comparison of the reflectance of the golf balls according to Example and Comparative Examples, it is determined that the reflectance of a golf ball has a little relationship with the degree of transparency of the dimple cover. The reflectance of a golf ball has a close relationship with glossiness due to the use of a matting agent. Therefore, it can be understood that, like Example, as the luminance of the golf ball where a transparent resin is coated with a matte coating agent is increased, specific wavelength emission effect of the pigment is increased by the light incident on the cover.

Experimental Example 4: Measurement of Luminance

[0089] Golf is a game in which a ball with a minimum diameter of 42.67 mm is hit in the state that the ball still stands on the ground. Therefore, as a golf ball is visually seen to be large, the performance is advantageously improved.

[0090] As the luminance becomes large, a golf ball is seen to be large. Therefore, the luminance of the golf balls of Example of the present invention and Comparative Example was measured. The reference light source used for the measurement had a luminance of 183.2 cd/m.sup.2, and a luminance meter was installed at a distance of 3 cm from the reference light source to measure the luminance (refer to Table 5).

TABLE-US-00005 TABLE 5 Type of Coating Layer Luminance Example Matte Coating Layer 32.46 cd/m.sup.2 Comparative Example 1 Glossy Coating Layer 32.07 cd/m.sup.2 Comparative Example 2 Matte Coating Layer 21.50 cd/m.sup.2 Comparative Example 3 Glossy Coating Layer 18.29 cd/m.sup.2 Comparative Example 4 Matte Coating Layer 145.5 cd/m.sup.2 Comparative Example 5 Glossy Coating Layer 168.4 cd/m.sup.2

[0091] With respect to golf balls manufactured by applying a glossy coating layer (Comparative Example 1) or a matte coating layer (Example) on a dimple cover manufactured by mixing only 0.2 parts by weight of a fluorescent material without adding TiO.sub.2 to a polymer resin (ionomer) the respective luminance of 32.07 cd/m.sup.2 and 32.46 cd/m.sup.2 was obtained. On the other hand, with respect to golf balls manufactured by applying a glossy coating layer (Comparative Example 3) or a matte coating layer (Comparative Example 2) on a dimple cover manufactured by adding 0.7 parts by weight of TiO.sub.2 to a polymer resin (ionomer) and mixing 0.3 parts by weight of a fluorescent material, the respective luminance of 18.29 cd/m.sup.2 and 21.50 cd/m.sup.2 was obtained. In comparison with the luminance obtained in Example described above, the luminance was measured to be lowered by 30 to 50%. With respect to golf balls manufactured by applying a glossy coating layer (Comparative Example 5) and a matte coating layer (Comparative Example 4) on a dimple cover manufactured by using only a polymer resin (ionomer) without adding TiO.sub.2 and a fluorescent material, the respective luminance of 168.4 cd/m.sup.2 and 145.5 cd/m.sup.2 was obtained. It is determined on the basis of the result that, since the luminance represents brightness of a light-emitting surface having a finite area, in Comparative Examples 4 and 5 where the transmittance and the reflectance relatively large in comparison with the coating layer applied to Example and Comparative Examples 1, 2, and 3, the luminance value is very high.

Experimental Example 5: Measurement of Visibility

[0092] A golf ball hit with a driver at 110 mile/hr may fly 250 m or more. At this time, the golf ball needs to be visible until the golf ball falls on the fairway. Even though the golf ball may not be seen at the end of the fly depending on weather conditions and playing time, the visibility needs to be good so that the golf ball can be found as far away as possible. In the related art, one of reason why the golf ball is manufactured in white is the visibility of the golf ball. In addition, the reason why bright, clear color golf balls containing a fluorescent material like orange golf balls, yellow golf balls, and the likes have been developed is also the visibility of the golf ball. In order to evaluate the visibility of the golf ball according to the present invention, it was tested whether or not five professional golfers at distances of 50 m, 100 m, 150 m, 200 m, and 250 m from the position of the golf ball according to the present invention in the field can recognize the golf ball. The visibility test was performed on the matte coating layer-transparent dimple cover-fluorescent golf ball according to Example, the matte coating layer-nontransparent dimple cover-fluorescent golf ball according to Comparative Example 2, and the glossy coating layer-transparent dimple cover-nonfluorescent golf ball according to Comparative Example 5 (refer to Table 6). In the test, visibility values (1 to 10; the higher the value, the more easily the golf ball is seen) scored by the five professional golfers are averaged. The value of 0 to 2.5 is marked by X; the value of 2.5 to 5 is marked by ; the value of 5 to 7.5 is ; and the value of 7.5 to 10 is marked by . In Table 6, denotes that the golf ball is seen vey well as distinguished from the field grass I; denotes that the golf ball is seen well as distinguished from the field grass; denotes that the golf ball is seen as distinguished from the field grass; and X denotes that the golf ball is not seen as distinguished from the field grass.

TABLE-US-00006 TABLE 6 Distance Comparative Comparative Example Example 2 Example 5 Matte Coating Matte Coating Glossy Coating Layer- Layer- Layer- Transparent Nontransparent Transparent Dimple Cover- Dimple Cover- Dimple Cover- Fluorescent Fluorescent Nonfluorescent Distance Golf Ball Golf Ball Golf Ball 50 m 100 m 150 m X 200 m X 250 m X X

[0093] As the result of the visibility test, the matte coating layer-transparent dimple cover-fluorescent golf ball according to Example was evaluated to be seen well to be distinguished from the field grass at a distance of 200 m from the field and to be seen to be distinguished from the field grass at a distance of 250 m. The matte coating layer-nontransparent dimple cover-fluorescent golf ball according to Comparative Example 2 was evaluated to be seen to be distinguished from the field grass at a distance of 150 m from the field and to be seen not to be distinguished from the field grass at a distance of 250 m or more. The glossy coating layer-transparent dimple cover-nonfluorescent golf ball according to Comparative Example 5 was evaluated to be seen to be distinguished from the field grass at a distance of 100 m from the field and to be seen not to be distinguished from the field grass at a distance of 100 m or more. The specific examples described in the specification are representatives of preferred examples of the present invention, and the scope of the present invention is not limited thereto. It will be apparent to the skilled in the art that modifications and other uses of the present invention do not depart from the scope of the invention disclosed in the claims.