ALKALI-FREE GLASS, ALKALI-FREE GLASS SUBSTRATE, AND PROCESS FOR PRODUCING THE SAME

摘要

A glass composition is designed which satisfies various properties required of glasses for liquid-crystal displays, etc., especially satisfies properties such as meltability and unsusceptibility to devitrification, and which is reduced in the content of ingredients harmful to the environment or contains substantially none of such ingredients. A glass substrate less harmful to the environment is obtained therefrom. The alkali-free glass is characterized by having a glass composition which comprises, in terms of oxide amount in wt.%, 50-70% SiO₂, 10-20% Al₂O₃, 8-12% B₂O₃, 0-3% MgO, 4-15% CaO, 0-10% SrO, 0-1% BaO, and 0-5% ZnO and containing substantially none of the alkali metal oxides and As₂O₃.