	US 12,415,902 B2
	Adhesive for tennis ball
Takehiko Hyodo, Kobe (JP); Yuko Kujirai, Kobe (JP); and Kazuyoshi Shiga, Kobe (JP)
Assigned to SUMITOMO RUBBER INDUSTRIES, LTD., Kobe (JP)
Filed by SUMITOMO RUBBER INDUSTRIES, LTD., Kobe (JP)
Filed on Jun. 23, 2022, as Appl. No. 17/847,785.
Claims priority of application No. 2021-116341 (JP), filed on Jul. 14, 2021.
Prior Publication US 2023/0024062 A1, Jan. 26, 2023
Int. Cl. A63B 39/00 (2006.01); C08K 3/04 (2006.01); C09J 11/04 (2006.01); C09J 109/00 (2006.01); A63B 102/02 (2015.01)

CPC C08K 3/04 (2013.01) [A63B 39/00 (2013.01); C09J 11/04 (2013.01); C09J 109/00 (2013.01); A63B 2039/006 (2013.01); A63B 2102/02 (2015.10); A63B 2209/00 (2013.01)]

4 Claims

1. A tennis ball comprising a hollow core made of a rubber material, wherein

the core includes two hemispherical half cores,

the two half cores are adhered to each other by an adhesive,

the adhesive comprises a base rubber and a filler,

the base rubber contains, as a main component thereof, liquid rubber such that a ratio of the liquid rubber to the base rubber is not less than 99% by mass,

the liquid rubber has a number average molecular weight of not less than 10,000,

the liquid rubber is isoprene rubber or butadiene rubber, and

the filler has an average nitrogen specific surface area of not less than 40 m²/g.