| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a ball for a ball game, which is excellent in ball hitting feeling, can lengthen the carry of the ball when hit and is also excellent in durability. <P>SOLUTION: The ball for a ball game has a diameter of 50 to 70 mm and includes a sphere, a first surrounding layer which covers the sphere, and the outer surrounding layer of one or more layers which covers the first surrounding layer. The sphere has the Shore D material hardness value of 46 to 65 and the first surrounding layer has the Shore D material hardness value of 45 to 75, and at the same time the shore D material hardness value of the spherical surface is less than 50. <P>COPYRIGHT: (C)2010,JPO&INPIT |
