MOLD FOR MAKING DISC SUBSTRATE, PROCESS FOR PRODUCING MOLD AND DISC SUBSTRATE

摘要

A disc substrate molding metal mold apparatus adapted for molding synthetic resin material to carry out molding of disc substrate of an information signal recording medium. This metal mold apparatus is adapted so that smoothing layers of metal are integrally formed on the molding plane surface sides of a first metal mold serving as the fixed side and a second metal mold serving as the movable side which are butted to each other to constitute a molding portion for molding disc substrate, and uneven patterns corresponding to information signals, etc. formed at the disc substrate are directly formed at the metallic layers, thus to carry out molding of disc substrate in which the surface is flattened with high accuracy, and uneven patterns of the metal mold side are transferred without allowing local undulations and/or projections occurring on the disc surface to take place.