| 摘要 |
<p>Record disc for the play-back of sound or video signals consists of a central carrier disc which is enclosed in two layers of an electrically non-conductive material. The outer layers consist of a vinyl plastic material, and the carrier disc is made of a different material such as an insulating material, impregnated with a conductive liquid. Holes around the centre hole of the disc are filled with conductive material and are joined on both sides by the bonded labels which are made of an electrically conductive material. This eliminates electrostatic charges, caused by friction of needle and grooves during play-back.</p> |
