| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a hollow golf ball which is small in impact force and is good in feeling at the time of hit without impairing flying performance. SOLUTION: This golf ball consists of a hollow core (4) consisting of a hollow part (1) and >=1 layer of hollow core outer layer part (2) consisting of a compsn. for the core mainly composed of rubber, resin or their mixture and a cover (3) formed on this hollow core 4. When the secondary natural frequency of the hollow golf ball is defined as X (kHz) and the deformation quantity when the hollow golf ball is loaded with a final load 130 kgf from the state the ball is loaded with an initial load 10 kgf as Y (mm), (X-Y) is in a range of 0.1 to 1.5.</p> |
