| 摘要 |
PROBLEM TO BE SOLVED: To realize a ball for a ball game which can be easily found even on a mallet golf course and enhance its productivity. SOLUTION: After a molding is released, a mallet ball is delivered in such a state that a first runner part 11 and a second runner part 12 are attached to a ball body part 10. Next, the ball body part 10 is retained with the ball body part 10 soaked completely into the shallow water of a water tank by fixing the runner parts 10, 11 of the molding or supporting the runner parts 10, 11 so that the parts 10, 11 are not afloat on the water level. The ball body part 10 is uniformly cooled while receiving an almost uniform pressure from the surroundings by immersing the ball body part 10 into water. |
