| 摘要 |
<p>PURPOSE:To make it difficult to cause a thread breakage by forming a cover thread by a multifilament, and winding the cover thread in such a manner that the central axis of its single fiber and a line crossing at a right angle to the central axis of a core thread make a specified narrow angle. CONSTITUTION:A single fiber 12a forming the cover thread 12 of a gut 10 is twisted at a twisting angle of about 30 deg., and the narrow angle made by the central axis W2 of the single fiber 12a and a line Y crossing at a right angle to the center axis X of a core thread 11 is 15 deg. or less, for example, about +5 deg.. When the thus constituted gut is used as the vertical thread of a tennis racket, the gut slides in the lateral direction (F, F' direction) and receives a friction from a lateral thread, but as the central axis W2 of the single fiber forming the cover thread 12 is disposed nearly along the F, F' direction, the friction from the lateral thread is received in the direction nearly along this central axis. Thus, the influence of friction is made difficult to be linked with abrasion and breakdown.</p> |
