Racket

Abstract

A face of a racket includes a plurality of first longitudinal threads, a plurality of second longitudinal threads, and a plurality of transverse threads. The first longitudinal threads and the second longitudinal threads are arranged alternately from a center of the face toward outside in a width direction of the racket. A material of each first longitudinal thread is different from a material of each second longitudinal thread. A tension of the first longitudinal thread may be different from a tension of the second longitudinal thread. Preferably, a ratio (N1/N2) of a number N1 of the first longitudinal threads to a number N2 of the second longitudinal threads is greater than or equal to 2/8, but less than or equal to 8/2.

What is claimed is: 
     
         1 . A racket comprising:
 a head; and   a face whose contour is formed by the head, wherein   the face includes a plurality of first longitudinal threads, a plurality of second longitudinal threads, and a plurality of transverse threads, and   specifications of each first longitudinal thread are different from specifications of each second longitudinal thread.   
     
     
         2 . The racket according to  claim 1 , wherein
 a material of the first longitudinal thread is different from a material of the second longitudinal thread.   
     
     
         3 . The racket according to  claim 2 , wherein
 the material of the first longitudinal thread is a resin composition whose base material is a polyester, and   the material of the second longitudinal thread is a resin composition whose base material is a nylon.   
     
     
         4 . The racket according to  claim 2 , wherein
 the material of the first longitudinal thread is a resin composition whose base material is a polyester, and   the material of the second longitudinal thread is natural gut.   
     
     
         5 . The racket according to  claim 2 , wherein
 the material of the first longitudinal thread is a resin composition whose base material is a nylon, and   the material of the second longitudinal thread is natural gut.   
     
     
         6 . The racket according to  claim 1 , wherein
 an elongation rate E1 of the first longitudinal thread is different from an elongation rate E2 of the second longitudinal thread.   
     
     
         7 . The racket according to  claim 6 , wherein
 a ratio (E1/E2) of the elongation rate E1 of the first longitudinal thread to the elongation rate E2 of the second longitudinal thread is less than or equal to 48/52, or is greater than or equal to 52/48.   
     
     
         8 . The racket according to  claim 1 , wherein
 a tension T1 of the first longitudinal thread is different from a tension T2 of the second longitudinal thread.   
     
     
         9 . The racket according to  claim 8 , wherein
 a ratio (T1/T2) of the tension T1 of the first longitudinal thread to the tension T2 of the second longitudinal thread is less than or equal to 48/52, or is greater than or equal to 52/48.   
     
     
         10 . The racket according to  claim 1 , wherein
 a ratio (N1/N2) of a number N1 of the first longitudinal threads to a number N2 of the second longitudinal threads is greater than or equal to 2/8, but less than or equal to 8/2.   
     
     
         11 . The racket according to  claim 1 , wherein
 each of the first longitudinal threads is adjacent to one or two of the second longitudinal threads, and   each of the second longitudinal threads is adjacent to one or two of the first longitudinal threads.   
     
     
         12 . The racket according to  claim 11 , wherein
 the first longitudinal threads and the second longitudinal threads are arranged alternately from a center of the face toward outside in a width direction of the racket.