Glass composition for chemical strengthening, and chemically strengthened glass article

Abstract

To provide a glass composition for chemical strengthening excellent in alkali resistance and suitable for combining surface compressive stress and compressive stress layer depth.SOLUTION: A glass composition contains, by the molar% expression, SiO2: 60 to 80%, Al2O3: 1 to 5%, MgO: 5 to 25%, CaO: 0 to 5%, Na2O:10 to 20%, and K2O: 0 to 10%, as components. By using this glass composition, a chemically strengthened glass article having, for example, a surface compressive stress of 500 MPa or larger and a compressive stress layer depth of 10 μm or larger becomes possible to be provided. By using the glass composition, it is also possible to provide a chemically strengthened glass article having, for example, the surface compressive stress of 650 to 950 MPa, and the compressive stress layer depth in the range of 7 to 15 μm.SELECTED DRAWING: None