| 摘要 |
<p>A bearing ring for an optical disk has sufficiently high firmness and satisfactory sliding properties. The ring (38) is formed by cutting a laminate structure comprising a first layer (42) formed of a firm film of material having a sufficiently high modulus of rigidity and second layer (44) formed of a film having a very low coefficient of sliding friction. The first layer (42) is preferably a film of polyethylene terephthalate and the second layer (44) is preferably a polyethylene having a very high molecular weight of one million or more. The second layer can also be formed of nylon 6, 6, polyacetal and fluorocarbon resins. <IMAGE></p> |
