| 摘要 |
PROBLEM TO BE SOLVED: To manufacture a glass substrate that is decreased in the number of defects of an aggregate of platinum group metal even if the aggregate of platinum group metal is mixed with molten glass during a manufacturing process.SOLUTION: A manufacturing method for a glass substrate comprises: as a process of processing molten glass by a glass processing device which has a wall, surrounding a vapor phase space, made at least partially of a material including platinum group metal, a molten glass processing process in which an aggregate of volatile matter of platinum group metal present in the vapor phase space and vaporizing from the wall is mixed as foreign matter; and an aggregate processing process of dissolving at least part of the aggregate mixed with the molten glass in the molten glass processing process in the molten glass. In the aggregate processing process, saturation solubility of the platinum group metal is adjusted by adjusting the rate of a time when the aggregate processing process occupies the molten glass processing process based upon the number of defects of the aggregate detected with respect to a glass substrate manufactured using the glass processing device so that the number of defects of the aggregate included in a glass substrate to be newly manufactured is at an allowable level.SELECTED DRAWING: Figure 1 |
