An aqueous adhesive for rubber of the present disclosure includes: a base agent containing rubber latex as a main component thereof; and an organic solvent that causes swelling of a rubber component in the rubber latex. An amount of the organic solvent in the aqueous adhesive for rubber is not less than 25% by mass and not greater than 60% by mass of a total amount of the base agent and the organic solvent. A boiling point of the organic solvent is preferably not higher than 140° C. A tennis ball of the present disclosure includes a hollow core made of a rubber material. The hollow core includes two hemispherical half cores. The two half cores are adhered to each other by using the aqueous adhesive for rubber.

An aqueous adhesive for rubber of the present disclosure includes: a base agent containing rubber latex as a main component thereof; and an organic solvent that causes swelling of a rubber component in the rubber latex. An amount of the organic solvent in the aqueous adhesive for rubber is not less than 25% by mass and not greater than 60% by mass of a total amount of the base agent and the organic solvent. A boiling point of the organic solvent is preferably not higher than 140° C. A tennis ball of the present disclosure includes a hollow core made of a rubber material. The hollow core includes two hemispherical half cores. The two half cores are adhered to each other by using the aqueous adhesive for rubber.

A pickle ball includes: a hollow ball with multiple holes on the surface, and a sound absorbing material filled to reduce noise inside the hollow ball, wherein the sound absorbing material includes a sponge, at least one or more LEDs are installed in the sound absorbing material, and a predetermined fluorescent material is applied to the surface of the hollow ball.

A pickle ball includes: a hollow ball with multiple holes on the surface, and a sound absorbing material filled to reduce noise inside the hollow ball, wherein the sound absorbing material includes a sponge, at least one or more LEDs are installed in the sound absorbing material, and a predetermined fluorescent material is applied to the surface of the hollow ball.

A ball, and in particular a baseball or softball, including one or more sensors such as accelerometers and/or inertial measurement units, and systems and methods using the same to improve a pitcher's pitching performance are described herein. In some embodiments, the ball may include one or more inertial measurement units and/or accelerometers capable of monitoring motion of the ball while it is thrown. Various types of pitches may be selected, and in response to the inertial measurement unit(s) and/or accelerometer(s) detecting certain parameters corresponding to a selected pitch, one or more indicators may be caused to perform an action. For example, one or more illuminating elements located on the ball may turn a first color in response to detecting parameters corresponding to the selected pitch.

A ball, and in particular a baseball or softball, including one or more sensors such as accelerometers and/or inertial measurement units, and systems and methods using the same to improve a pitcher's pitching performance are described herein. In some embodiments, the ball may include one or more inertial measurement units and/or accelerometers capable of monitoring motion of the ball while it is thrown. Various types of pitches may be selected, and in response to the inertial measurement unit(s) and/or accelerometer(s) detecting certain parameters corresponding to a selected pitch, one or more indicators may be caused to perform an action. For example, one or more illuminating elements located on the ball may turn a first color in response to detecting parameters corresponding to the selected pitch.

A tennis ball including a spherical core. The spherical core including an outer surface and a raised wall integrally molded as part of the outer surface.

A tennis ball including a spherical core. The spherical core including an outer surface and a raised wall integrally molded as part of the outer surface.

A method for forming a tennis ball including the steps of providing a non-foamed thermoplastic core and providing a non-smooth textured surface on the core. The thermoplastic core including a thermoplastic material having a specific gravity of 0.86 to 1.38, a flexural modulus of 2.0 to 50.0 MPa, and a Shore D hardness of 10 to 70. The thermoplastic material having a thickness between 3.0 and 8.0 mm. The thickness of the thermoplastic material being configured to maintain dimensional stability at internal pressures of between zero and 15 psi.

A method for forming a tennis ball including the steps of providing a non-foamed thermoplastic core and providing a non-smooth textured surface on the core. The thermoplastic core including a thermoplastic material having a specific gravity of 0.86 to 1.38, a flexural modulus of 2.0 to 50.0 MPa, and a Shore D hardness of 10 to 70. The thermoplastic material having a thickness between 3.0 and 8.0 mm. The thickness of the thermoplastic material being configured to maintain dimensional stability at internal pressures of between zero and 15 psi.