A golf ball dimple pattern based on a square dipyramid, i.e., two square pyramids connected base-to-base, is disclosed. The dimples are arranged within four substantially identical triangular sections on each of two substantially identical hemispheres of the ball.

Embodiments of golf balls and methods to manufacture golf balls are generally described herein. In one example, a golf ball may include a face regions and a plurality of edge regions. Each face region may include first, second, and third triangular regions, each with a set of dimples. Other examples and embodiments may be described and claimed.

A golf ball dimple pattern based on a square dipyramid, i.e., two square pyramids connected base-to-base, is disclosed. The dimples are arranged within four substantially identical triangular sections on each of two substantially identical hemispheres of the ball.

The present disclosure relates to a golf ball, wherein dimples having an extraordinary flight performance by combining the advantages of both circular dimples and polygonal dimples in the related art, in other words, by arranging the combined dimples that give depth to the face of the combined polygon and circle of the same center on the surface of the sphere, the trajectory is bent due to the influence of wind, which is a disadvantage of the conventional polygonal dimples. It is excellent in flight straightness by eliminating the effect, and when flying after hitting, the vertex region, which acts as a small bluff body, rotates and breaks the pressure in advance, causing a quick turbulent transition, and it becomes like an arc of a circular dimple instead of the sides of the general polygonal dimples.

A golf ball 2 includes a core 4, a mid layer 6, a cover 8, and dimples 10. A difference DH in hardness between a surface and a central point of the core 4, a thickness Tm and a hardness Hm of the mid layer 6, a thickness Tc and a hardness Hc of the cover 8, and an amount of compressive deformation Sb meet the following mathematical formulas.

(DH*Hm)/(Hc*Tc)>80

((Sb*Tc)/(Hc* Hm*Tm))*1000>0.75

An area ratio So of dimples 10 and a ratio Rs of a number of the dimples 10 each having a diameter of equal to or greater than 9.60% but equal to or less than 10.37% of a diameter of the golf ball 2 meet the following mathematical formula (3).

Rs≧−2.5*So+273   (3)

A golf ball 2 has a large number of dimples 10 on a surface thereof. The contours of the dimples 10 are non-circular. A standard deviation of areas of the dimples 10 is equal to or less than 1.7 mm.sup.2. A ratio of a total area of the dimples 10 relative to a surface area of a phantom sphere of the golf ball 2 is equal to or greater than 80%. By comparting lines CS obtained by projecting sides of a regular dodecahedron, which is inscribed in the phantom sphere, onto the phantom sphere, a surface of the phantom sphere can be divided into 12 units Ut each of which meets the following mathematical formula (I):
−2≦(Nt/12)−Nu≦2  (I),
where Nt represents the total number of the dimples 10 and Nu represents the number of the dimples 10 on one unit.

The present invention is directed to golf balls having improved aerodynamic performance due, at least in part, to the alteration of the dimple surfaces. In particular, the present invention relates to a golf ball that includes at least a portion of its dimples having circular perimeters and dimple profiles having a concentric groove or a non-concentric groove on the surface of the dimple. The golf ball dimples of the present invention provide golf ball surfaces having unique appearances, while maintaining ideal aerodynamic characteristics.

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.

A surface of a sphere is divided by using not only great circles but also small circles, forming a spherical polyhedron. The spherical polyhedron includes two spherical regular pentagons, each having a center at the pole, ten spherical isosceles triangles near the pole, ten spherical pentagons near the equator, and ten other spherical isosceles triangles near the equator. Compared to a related art, dimples are accurately arranged in spherical polygons. Thus, a dimple area ratio is improved and the number of dimples is appropriately maintained.

In a golf ball including dimples having coma shapes, the dimples are arranged such that one comma shaped dimple replaces a circular dimple, two or more comma shaped dimples of different sizes replace one circular dimple, comma shaped dimples having different shapes are arranged in a mixed type arrangement, circular dimples and comma shaped dimples are arranged in a mixed type arrangement, or a discontinuous annular dimple is added to the comma shaped dimples. Thus, a disadvantage of a large circular dimple may be removed and simultaneously a golf ball with stable flight capability and a long flight distance may be provided.