| 摘要 |
<p>PURPOSE: To obtain a short distance golf ball used in a short golf course by using a ball which has such a density gradient as to increase along its radius from the center to the surface, a high density outer coat, a cell-like core structure and a specified repulsiveness. CONSTITUTION: This golf ball 10 has a diameter of about 1.68 inch which is the same as that of an ordinary golf ball and a weight ranging from about 15g to 30g though the ordinary golf ball is about 45g. The cross section of the golf ball 10 has an outer high density facing layer 22 which is increased in the density of thermoplastic resin material 12 from the center 20 to the surface 14 along the radius 16 of the golf ball, and has a thickness ranging from 0.125 inch to 0.625 inch. The density distribution of thermoplastic resin material in the golf ball ensures that the golf ball is executed similarly to the ordinary golf ball in most points except that the flying distance of the golf ball will be shorter. This short distance golf ball has elastic repulsive ratio of 50% to 80%.</p> |
