METHOD FOR PRODUCING GLASS SUBSTRATE FOR MAGNETIC DISKS

摘要

This method for producing a glass substrate for magnetic disks comprises: a step wherein a plate glass blank is held on a carrier and the main surface of the plate glass blank is polished by a polishing machine using abrasive grains having a Mohs hardness (old Mohs hardness) of 8 or more as free abrasive grains; and a step wherein an adhesion prevention layer for preventing the free abrasive grains from adhering to a lateral wall surface that is positioned in an outer peripheral portion of the plate glass blank, said outer peripheral portion being in contact with the carrier, is formed before polishing the main surface. A magnetic disk which uses a glass substrate for magnetic disks produced by this method is not susceptible to problems such as head crash and thermal asperity.