Apparatus and process for manufacturing substrate sheet for information recording mediums.

摘要

An apparatus for manufacturing a substrate sheet for information recording mediums is disclosed. The apparatus comprises a roll stamper (24) comprising a flexible stamper member (21) having a pattern corresponding to a preformat for an information recording medium, fixed along the corresponding periphery of a roll substrate, a specular roll provided opposingly to the roll stamper (14)(16), and a means for melt-extruding (11) a resin and stamping-molding a molten-resin sheet having a larger width than the flexible stamper member. The means for stamping-molding the molten-resin sheet is so provided that the molten-resin sheet is extruded to the gap between said roll stamper and said specular roll. In the apparatus a means for controlling temperature is provided, so that a temperature difference on the surfaces of edges and preformat pattern transfer area of the resin sheet is kept within 30 DEG C when the resin sheet is separated from said roll stamper after the molten-resin sheet has been pressed between said roll stamper and said specular roll. According to the present invention, there is provided an apparatus for manufacturing a substrate sheet for information recording mediums, which can allow to reduce the influence of the resin sheet edges on the preformat pattern transfer area and can obtain a substrate sheet for information recording mediums much improved in birefringence-free properties and preformat pattern transfer performance, and a process for manufacturing it. <IMAGE>