A monofilament string for use in string racket sports, wherein the monofilament string comprises: a covering material; a core material embedded in the covering material, wherein the core material comprises: a sea region comprising a thermoplastic elastomer; and a plurality of island regions comprising a thermoplastic plastic doped with one or more doping agents, wherein the plurality of island regions is embedded in the sea region; and wherein a geometry and/or a distribution of the island regions in the sea region is such that a tangent modulus of a stress-strain curve of the monofilament string increases with increasing strain in a playing stress range.

In a tennis racket, longitudinal strings extending in a longitudinal direction and transverse strings extending in a transverse direction intersect each other to form a plurality of meshes. At a center, in the transverse direction, of a head, a ratio of an area St of a tip mesh located closest to a tip in the longitudinal direction relative to an area Sc of a center mesh located at a center in the longitudinal direction is not less than. The center mesh is formed in a rectangular shape having short sides in the longitudinal direction and long sides in the transverse direction. Preferably, from the center mesh to the tip mesh, an area of each mesh is set so as to be not larger than an area of a mesh adjacent thereto at a tip side.

In a tennis racket, longitudinal strings extending in a longitudinal direction and transverse strings extending in a transverse direction intersect each other to form a plurality of meshes. At a center, in the transverse direction, of a head, a ratio of an area St of a tip mesh located closest to a tip in the longitudinal direction relative to an area Sc of a center mesh located at a center in the longitudinal direction is not less than. The center mesh is formed in a rectangular shape having short sides in the longitudinal direction and long sides in the transverse direction. Preferably, from the center mesh to the tip mesh, an area of each mesh is set so as to be not larger than an area of a mesh adjacent thereto at a tip side.

A string set is a string set strung on a racket as a main string and a cross string, and is configured to include a first string strung as any one of the main string and the cross string and has a small friction force and a small diameter and a second string strung as another one of the main string and the cross string and has a larger friction force and a larger diameter than the diameter and the surface friction force of the first string. This distributes functions to the first string and the second string to obtain both the hairpin performance, which is improved by the large surface friction force and outer diameter of the string, and the cut smash performance, which is improved by the small surface friction force and outer diameter of the string, at the same time.

A string set is a string set strung on a racket as a main string and a cross string, and is configured to include a first string strung as any one of the main string and the cross string and has a small friction force and a small diameter and a second string strung as another one of the main string and the cross string and has a larger friction force and a larger diameter than the diameter and the surface friction force of the first string. This distributes functions to the first string and the second string to obtain both the hairpin performance, which is improved by the large surface friction force and outer diameter of the string, and the cut smash performance, which is improved by the small surface friction force and outer diameter of the string, at the same time.

The present invention relates to a ball game racket with strings that comprise at least one string comprising a superelastic material.

The present invention relates to a ball game racket with strings that comprise at least one string comprising a superelastic material.

A sports mat system incorporating a reversible thermochromic leuco dye includes an impact pad portion having a reversible thermochromic leuco dye incorporated into it in order to provide a temporary visual indication of the path of a sports apparatus swing. The impact portion changes color with a temperature change due to frictional contact between the pad and the equipment being swung, in order to visually illustrate the swing path of the club along with the club head/face orientation during impact. In another implementation, a racquet is provided incorporating a reversible thermochromic leuco dye into a portion of racquet strings to temporarily visually illustrate the contact area between the racquet face and a ball being struck, in order to provide the user with feedback relating to characteristics of their swing.

A tennis racket with a more-responsive string configuration is an apparatus that allows a user to hit a tennis ball with spin and power in a controlled manner. The apparatus includes a closed-shape beam, a throat, an elongated handle, and a plurality of lines. The elongated handle allows the user to firmly grasp the apparatus, and the throat connects the elongated handle to the closed-shape beam. The plurality of lines is tensionably mounted within the closed-shape beam in order to provide the present invention with an elastic contact area for the tennis ball. Each of the plurality of lines includes a first string and a second string, which are positioned along each other for each of the plurality of lines. In addition, a lateral surface of the first string is positioned tangent to a lateral surface of the second string.

A shock absorber or a racket contains: a body and at least two magnetic elements. The body is mounted on strings of the racket and includes an accommodation groove defined therein, the at least two magnetic elements are housed in the accommodation groove of the body, wherein one of the at least two magnetic elements slides in the accommodation groove of the body, and the at least two magnetic elements are fixed at a same magnetic pole and face to each other so that magnetic repulsion produces between the at least two magnetic elements.