NEW TENNIS BALL Russian patent published in 2013 - IPC A63B37/00 

FIELD: sports.

SUBSTANCE: claimed invention relates to a tennis ball and a method of its manufacture. The tennis ball which is made of an elastomeric polyurethane foam material, having a shape as a ball and the density of 250-800 kg/m³. The foam material is covered with textile material and where the foam material is prepared by interacting of an aromatic polyisocyanate and a polyol containing at least 30% by weight of polyol having a level of unsaturation of 0.03 mEq/g, with the use of a blowing agent. Polyol having a level of unsaturation of 0.03 mEq/g, is selected from polyester polyols, polyoxypropylene polyols, polyoxyethylene polyoxypropylene polyols, polyoxyethylenepolyols, polyoxybutylenepolyols, polyoxyalkylenepolyols containing oxybutylene group with oxyethylene and/or oxypropylene groups, complex polyoxyalkylenepolyether-polyols and mixtures of such polyols provided that the use of polyoxyethylene-polyoxypropylene polyol is excluded having oxyethylene content equal to 50-90% by weight based on the weight of polyol as the only polyol having a level of unsaturation of 0.03 mEq/g.

EFFECT: improved reliability and durability of the ball, which is achieved by maintaining the operating performance of the ball during its operation.

6 cl