MANUFACTURING METHOD FOR GLASS SUBSTRATE AND MANUFACTURING APPARATUS FOR GLASS SUBSTRATE

摘要

PROBLEM TO BE SOLVED: To provide a manufacturing method for a glass substrate and a manufacturing apparatus for a glass substrate that reduce formation of a stria by efficiently discharging glass foreign matter from an agitation device and uniformly stirring molten glass.SOLUTION: A stirring process comprises stirring molten glass G by a stirring device 100 comprising a stirring container 101 and a stirrer 102. A discharging process comprises discharging glass foreign matter formed on a glass liquid surface GL in the stirring container 101 from a discharge port 111a provided to a side wall of the stirring container 101. The discharging process comprises a first discharging process and a second discharging process alternately each at least once respectively. The first discharging process comprises discharging glass foreign matter from a discharge port 111a with a stirrer 102 at a stop. The second discharging process comprises discharging the glass foreign matter from the discharge port 111a while the stirrer 102 stirs the molten glass G in a stirring container 101.SELECTED DRAWING: Figure 6