GLASS-SUBSTRATE MANUFACTURING METHOD

摘要

A glass-substrate manufacturing method which includes a forming step and a cooling step. In the forming step, a molten glass is formed into a sheet glass by a down-draw process. In the cooling step, the sheet glass is cooled. The cooling step includes first, second and third coating steps as defined herein.

主权项

1. A glass-substrate manufacturing method comprising
a forming step of forming a molten glass into a sheet glass by a down-draw process, and a cooling step of cooling the sheet glass, wherein: the cooling step includes
a first cooling step of cooling the sheet glass at a first average cooling rate until the temperature of a central region of the sheet glass drops to the annealing point,a second cooling step of cooling the sheet glass at a second average cooling rate until the temperature of the central region drops from said annealing point to a temperature 50° C. below the strain point, anda third cooling step of cooling the sheet glass at a third average cooling rate until the temperature of the central region drops from said temperature 50° C. below the strain point to a temperature 200° C. below the strain point; the first average cooling rate is 5.0° C./second or faster; the first average cooling rate is faster than the third average cooling rate; and the third average cooling rate is faster than the second average cooling rate.