| 摘要 |
<p>PURPOSE:To improve the feeling without damaging the advantage of using a solid center by gradually increasing the hardness of a single structure rubber ball used as a solid center from the central part toward the outside, and setting, to a specific value a hardness difference between the central part and the part inside from the outer surface by a specific dimension. CONSTITUTION:A spooled golf ball comprises a solid center 1, a yarn rubber layer 2 and a cover 3. The solid center 1 has such a hard outer and soft inner structure that the hardness is gradually increased from the central part toward the outside, and a hardness difference between the central part and the part 2mm inside from the outer surface is set to about 4 or more at JIS-C hardness. The hardness of the central part of the solid center 1 ranges from 35 to 45 by the JIS-C hardness, and the outside diameter of the solid center 1 ranges about from 26 to 31mm. The feeling of this golf ball is near a spooled golf ball using a liquid center, and has durability equal to that of a spooled golf ball using a solid center.</p> |
