| 摘要 |
PROBLEM TO BE SOLVED: To avoid electric charges caused between a disc substrate and spacer to avoid the coating nonuniformity due to dust at time of forming of a protective film by lowering the surface resistance below specified value. SOLUTION: The surface region is set to 1×10<14>Ω/square cm or less. In stacking and holding optical discs on a stack pole 1, a space 6 is disposed between disc substrates 1 to avoid mutually contacting the disc substrates 1 to a stack pole brace 5, thereby avoiding scratching the surface of the substrate. The entire surface of the spacer made of a polycarbonate, the same material as that of the disc substrate, is dipped in a soln. of a siloxane type antistatic agent dispersed in a solvent at a uniform thickness, the outer diameter of the spacer is made smaller than the inner diameter of a stamper retaining groove formed into the disc surface, allowing the spacer to be disposed in the stamper retaining groove of the disc. Thus the coating uniformity in coating can be eliminated.
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