| 摘要 |
PURPOSE:To prevent infiltrating of a coating liquid to another surface side by inclining at least part of the outer end faces of a substrate toward the other surface side on the opposite side from the one surface side of the substrate. CONSTITUTION:The side end face 17 on the outermost periphery of the optically transparent disk substrate 11 inclines rectilinearly inward toward the other surface 18 on the opposite side from the one surface 12 side provided with pits 3 and a recording layer 4. Accordingly, the diameter of one surface is larger than the diameter of other surface 18. The outer end face of the substrate 11 is formed as a slope 17 in such a manner, by which the coating liquid tending to leak from the top end of the outer end face 17 and to infiltrate to the other side is prevented at the time of applying the coating liquid of the recording layer 4 on the substrate 11 while rotating the substrate. |
