The ball of the present invention is characterized by including at least one skin layer having water absorbability. The at least one skin layer may be formed of a water absorbent material, or may be formed so as to include a surface portion and a water absorbent outer skin adhered to at least a part of the surface portion. According to the ball of the present invention, a ball for competitions that can easily maintain water absorbency is provided while remaining durable even when used for a long time and not requiring man-hours during the manufacturing process.

The ball of the present invention is characterized by including at least one skin layer having water absorbability. The at least one skin layer may be formed of a water absorbent material, or may be formed so as to include a surface portion and a water absorbent outer skin adhered to at least a part of the surface portion. According to the ball of the present invention, a ball for competitions that can easily maintain water absorbency is provided while remaining durable even when used for a long time and not requiring man-hours during the manufacturing process.

One or more aspects of the present disclosure provide articles of manufacture and components of articles that incorporate an optical element that imparts structural color to the component or the article. The component comprises a cured or curable material, and can include or be made to have a textured surface.

A ball lifting device of the present disclosure, which employs a spiral ball transporting method for smoothly moving a ball, can move along a free path, is easy to be installed and operated, and has excellent durability and strength. The ball lifting device can be installed indoors as well as outdoors for educational, entertainment or viewing purposes. The ball lifting device can quickly move inflated balls filled with air used in ball games, and can be installed in connection with sports facilities as an automatic ball supply system.

A ball lifting device of the present disclosure, which employs a spiral ball transporting method for smoothly moving a ball, can move along a free path, is easy to be installed and operated, and has excellent durability and strength. The ball lifting device can be installed indoors as well as outdoors for educational, entertainment or viewing purposes. The ball lifting device can quickly move inflated balls filled with air used in ball games, and can be installed in connection with sports facilities as an automatic ball supply system.

One or more aspects of the present disclosure are directed to components having an optical element that imparts structural color to the component or article. The present disclosure is also directed to articles of manufacture including the component having an optical element, and methods for making components and articles having an optical element that imparts structural color.

A fitness device is provided, the fitness device comprising: a spheroidal member having an interior cavity, the spheroidal member comprising a cylindrical portion extending between a first hemispherical endcap and a second hemispherical endcap, wherein a surface of the spheroidal member defines an aperture positioned between the interior cavity and an exterior of the spheroidal member; and a structured surface positioned on the surface of the spheroidal member over the aperture, the structured surface extending into the interior cavity of the spheroidal member.

A fitness device is provided, the fitness device comprising: a spheroidal member having an interior cavity, the spheroidal member comprising a cylindrical portion extending between a first hemispherical endcap and a second hemispherical endcap, wherein a surface of the spheroidal member defines an aperture positioned between the interior cavity and an exterior of the spheroidal member; and a structured surface positioned on the surface of the spheroidal member over the aperture, the structured surface extending into the interior cavity of the spheroidal member.

Provided is a method for manufacturing an exercise ball which is made by using a pasted ball such as a soft leather ball and which has a lower impact value compared to a conventional yarn-wound ball. The exercise ball comprises a spherical hollow rubber bladder (2) in which compressed air is sealed, and a yarn-wound reinforcement layer (3) formed by evenly winding a filament yarn around the surface of the rubber bladder, wherein the exercise ball is characterized in that nylon filament yarn, obtained by hard twisting two 30-50 denier nylon filaments 1-a, 1-b in a single-direction twist is used as a winding yarn (1).

Provided is a method for manufacturing an exercise ball which is made by using a pasted ball such as a soft leather ball and which has a lower impact value compared to a conventional yarn-wound ball. The exercise ball comprises a spherical hollow rubber bladder (2) in which compressed air is sealed, and a yarn-wound reinforcement layer (3) formed by evenly winding a filament yarn around the surface of the rubber bladder, wherein the exercise ball is characterized in that nylon filament yarn, obtained by hard twisting two 30-50 denier nylon filaments 1-a, 1-b in a single-direction twist is used as a winding yarn (1).