| 摘要 |
PROBLEM TO BE SOLVED: To provide an inexpensive baseball ball which is used in practice or in practice games by coating the seaming of the ball with a durable reinforcing agent, thereby eliminating such drawbacks as an easy-to-wear and-cut of a sewing yarn forming stitches, and easy-to-rupture of leather in the peripheral part of sewing holes and the deterioration in performance such as in the repulsion, by infiltration of water from the seams of leather or the sewing holes. SOLUTION: The durable reinforcing agent is applied to the seaming of the baseball ball. The durable reinforcing agent applied to the seaming consists of a polyurethane prepolymer solution. |
