MOLD FOR MOLDING, MOLDING METHOD, POLISHING DEVICE FOR STAMPER, POLISHING METHOD FOR STAMPER, STAMPER AND OPTICAL INFORMATION RECORDING MEDIUM

摘要

PURPOSE: To improve the flow of a resin and to prevent the generation of strains and dislocation by changing the space in the mold for molding according to radii. ;CONSTITUTION: While the conventional stampers are plane, this stamper 1 has the thickness changing according to the radii. For example, the signal surface of the stamper 1 is stuck to a plate 8 meeting the shape of the stamper 1 desired to be obtd. by a polishing stage for the rear surface of the stamper 1 and is polished, by which the thickness in the diametral direction of the stamper 1 is freely controlled. Namely, the thickness is increased in the outer peripheral part of the range A in the radial direction of the stamper 1 in order to balance the flow of the resin and the thickness is made flat in order to improve the signals in the range B. The thickness is increased in order to decrease the strains of the resin in the range C. The thickness in this range is conversely decreased by the packing quantity of the resin, etc., in some cases. The flow of the resin is thereby improved and the generation of sink marks, strains and dislocation is prevented.;COPYRIGHT: (C)1994,JPO&Japio