Bridgestone Corporation

Jun Nomura

Keisuke Ihara

Jumei Harada

Masaaki Kaida

Yasuhide Alaki

Thread--wound golf balls are prepared by winding a rubber thread around a frozen core to form a core ball, immediately thereafter microwave heating the core ball to thaw the core, and forming a cover over the core ball. Microwave heating causes the frozen core to be briefly thawed without heating the thread rubber layer and without moisture condensation on the core ball surface, reducing the time taken for the core thawing step and eliminating the need for a drying step.

Preparation of thread-wound golf balls

A golf ball comprising a core having a thread rubber continuously wound thereon and a cover becomes more durable when at least 8 turns of every ten turns of thread rubber around the core have a crossing angle between two consecutive turns in the range of 12.degree. to 45.degree..

Thread wound golf ball

A golf ball having a plurality of recessed dimples in the surface thereof, wherein at least 90% in number of the dimples have a value of Vo in the range defined by the following equation:

Growing community of inventors

Yokohama, Japan

Jun Nomura