Ball for ball game and method of manufacturing the same
A golf ball including a spherical body, first regions, and second regions. The spherical body includes a core layer and a cover layer made from a synthetic resin covering the core layer. Dimples are formed in a surface of the cover layer. First regions that are electrically conductive are formed on a surface of the spherical body. The first regions are formed on a spherical surface having a center of the spherical body as a center. The first regions are positioned at six vertices of an imaginary regular hexahedron such that the vertices are positioned on the surface of the spherical body and, thus, six of the first regions are formed. The second regions are formed in areas of the surface other than where the first regions are formed. The second regions have a radio wave reflectance lower than that of the first regions.
1. A ball for a ball game, the ball being a spherical body and comprising:
a spherical core inside the spherical body, the spherical core being a sphere having a center of the spherical body as a center,
a spherical cover layer covering the spherical core, the spherical cover layer being a sphere having a center of the spherical body as a center,
first and second regions formed on a spherical surface of the spherical core or on a spherical surface of the spherical cover layer;
the first regions are formed of a first material, the first material being an electrically conductive material and having a radio wave reflectance, the first regions each having a diameter of not less than 2 mm and not more than 15 mm, and
the second regions are formed of a second material in areas other than where the first regions are formed, the second material being an electrically non-conductive material and having a radio wave reflectance lower than the radio wave reflectance of the first material.
2. The ball for a ball game according to claim 1 , wherein
three of the first regions are formed, and
the three of the first regions are positioned such that imaginary lines connecting the three first regions form an equilateral triangle including a diameter of the spherical body on a plane.
3. The ball for a ball game according to claim 2 , wherein
the ball for a ball game is a golf ball forming the spherical body,
the spherical surface having the center of the spherical body as a center is a surface of the golf ball,
the surface of the golf ball is constituted by a spherical surface formed by a multiplicity of dimples,
the first regions are formed on the dimples, and
the second regions are formed on areas of the spherical surface other than on the multiplicity of dimples.
4. The ball for a ball game according to claim 2 , wherein the spherical body is a golf ball, and wherein:
the spherical surface of the spherical core includes a multiplicity of dimples formed thereon; and
the spherical surface of the spherical cover layer includes a multiplicity of dimples, separate from said dimples;
the spherical cover layer is made from a material that allows passage of radio waves,
the first and second regions are formed on the spherical surface of the spherical core,
the first regions are formed on the multiplicity of dimples of the spherical surface of the spherical core, and
the second regions are formed on areas of the spherical surface of the spherical core other than on the multiplicity of dimples.
5. The ball for a ball game according to claim 1 , wherein the first regions are positioned at vertices of an imaginary regular polyhedron or a semiregular polyhedron such that the vertices are positioned on the spherical surface of the spherical core or on the spherical surface of the spherical cover layer.
6. The ball for a ball game according to claim 5 , wherein
the ball for a ball game is a golf ball forming the spherical body,
the first and second regions are formed on a surface of the golf ball,
the surface of the golf ball is constituted by a spherical surface formed by a multiplicity of dimples,
the first regions are formed on the dimples, and
the second regions are formed on areas of the spherical surface other than on the multiplicity of dimples.
7. The ball for a ball game according to claim 5 , wherein the spherical body is a golf ball, and wherein:
the spherical surface of the spherical core includes a multiplicity of dimples formed thereon; and
the spherical surface of the spherical cover layer includes a multiplicity of dimples, separate from said dimples;
the spherical cover layer is made from a material that allows passage of radio waves,
the first and second regions are formed on the spherical surface of the spherical core,
the first regions are formed on the multiplicity of dimples of the spherical surface of the spherical core, and
the second regions are formed on areas of the spherical surface of the spherical core other than on the multiplicity of dimples.
8. The ball for a ball game according to claim 1 , wherein the first regions form a circle having a diameter that is not less than 2 mm and not more than 15 mm, or a regular polygon having a diameter of an inscribed circle that is not less than 2 mm and not more than 15 mm.
9. The ball for a ball game according to claim 8 , wherein
the ball for a ball game is a golf ball forming the spherical body,
the first and second regions are formed on a surface of the golf ball,
the surface of the golf ball is constituted by a spherical surface formed by a multiplicity of dimples,
the first regions are formed on the dimples, and
the second regions are formed on areas of the spherical surface other than on the multiplicity of dimples.
10. The ball for a ball game according to claim 8 , wherein the spherical body is a golf ball, and wherein:
the spherical surface of the spherical core includes a multiplicity of dimples formed thereon; and
the spherical surface of the spherical cover layer includes a multiplicity of dimples, separate from said dimples;
the spherical cover layer is made from a material that allows passage of radio waves,
the first and second regions are formed on the spherical surface of the spherical core,
the first regions are formed on the multiplicity of dimples of the spherical surface of the spherical core, and
the second regions are formed on areas of the spherical surface of the spherical core other than on the multiplicity of dimples.
11. The ball for a ball game according to claim 1 , wherein:
a surface resistance of the first regions is not more than 130 Ω/sq,
the ball for a ball game is a hard ball for baseball,
the spherical body comprises a spherical and solid core layer as the spherical core, and the cover layer that covers the solid core layer,
the first and second regions are formed on an outer surface of the cover layer,
the cover layer is constituted by a plurality of outer coverings and electrically conductive stitching for stitching together the outer coverings,
the first regions are constituted by the stitching, and
the second region is constituted by the outer coverings.
12. The ball for a ball game according to claim 1 , wherein:
a surface resistance of the first regions is not more than 130 Ω/sq,
the ball for a ball game is a soft ball for baseball,
the spherical body comprises a spherical and hollow core layer as the spherical core, and the cover layer that covers the core layer,
the first and second regions are formed on an outer surface of the cover layer,
the cover layer comprises a band region formed extending band-like along a surface of the spherical body and a plurality of recesses and protrusions formed throughout an overall length of the band region, wherein
a reflecting portion having radio wave reflectability is formed in the recesses and/or the protrusions that constitute the plurality of recesses and protrusions,
the first region is constituted by the reflecting portion, and
the second region is constituted by an area of the cover layer other than the reflecting portion.