METHOD FOR MANUFACTURING GLASS SUBSTRATE AND GLASS BLANK FOR MAGNETIC DISK, AND GLASS SUBSTRATE AND GLASS BLANK FOR MAGNETIC DISK

摘要

Provided is a method for efficiently manufacturing glass substrates for magnetic disks in which surface irregularity of the main surface is suppressed, and also provided is a glass substrate for a magnetic disk. When a glass substrate for a magnetic disk having a pair of main surfaces is manufactured, a glass blank is moulded by performing pressing at planar press-moulding faces of a metal mould so as to pinch molten glass or softened glass from both sides. The glass blank is then polished. During pressing of the glass blank, the temperature conditions around the pair of main surfaces of the glass blank are made uniform.