Na 2 O 11 - 20 mass

摘要

PROBLEM TO BE SOLVED: To provide a tempered glass substrate with which the treating time is shortened and the productivity is thereby enhanced when cover glass used for a solid-state imaging device is subjected to ion exchange, and to provide a method for manufacturing the tempered glass substrate.;SOLUTION: The method of manufacturing a tempered glass substrate includes a process of preparing a raw material to be a glass containing an alkali metal oxide and having a heat expansion coefficient in the temperature range of 30 to 380°C of 30 to 100×10^-7/°C, a process of melting the raw material in a melting vessel and then molding it as tabular by an overflow down draw method, and a process of applying the molded tabular glass to an ion exchange and forming a compressive stress layer on its surface.;COPYRIGHT: (C)2014,JPO&INPIT