Patent ID: 8318243

Claim:
A method for manufacturing an optical information recording medium, the method comprising: laminating plural layers successively on a substrate having a through-hole at its center; and fitting center caps each having a predetermined radius in the through-hole to form at least two of the plural layers by a spin coat method; wherein a radius of a first center cap used for forming an upper layer of the at least two layers is larger than a radius of a second center cap used for forming a lower layer thereof, and wherein each of the center caps includes: a fitting part fitted in the through-hole, a cone-shaped part that is provided concentrically with the fitting part, made parallel to the substrate, and has an end surface that is an annular-shaped plane having a diameter larger than a diameter of the fitting part, a projection part provided concentrically with the cone-shaped part at its upper part and an air introduction hole that penetrates the projection part and the fitting part, wherein the air introduction hole includes an opening part at an upper surface of the projection part, an opening part at a lower surface of the fitting part and opening parts at each side surface of the fitting part.