摘要 |
A substrate for an information recording medium, which has high heat resistance and high acid resistance and is formed of a glass having a glass transition temperature (Tg) of 600° C. or higher and having an etching rate of 0.1 mum/minute or less with regard to a hydrosilicofluoric acid aqueous solution that is maintained at a temperature of 45° C. and has a hydrosilicofluoric acid concentration of 1.72% by weight, and an information recording medium having an information recording layer formed on the above substrate.
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