| abstract |
An object of the present invention is to provide a chemically tempered glass that is excellent in acute-angled object scratching strength, has high safety during crushing, and has a high ion exchange rate. SOLUTION: The thickness t is 2 mm or less, the compressive stress value (CS 40 ) at a depth of 40 μm from the surface is 60 MPa or more, the surface compressive stress value (CS) is 450 MPa or more, and the depth from the DOL to the surface side is 20 μm. ΔCS DOL-20 (unit: MPa / μm) calculated by the following formula using the compressive stress value CS DOL-20 is 4.0 or less, and the mother composition is expressed in mol% based on oxide, and SiO 2 58 to 72%, the Al 2 O 3 7 to 20% of Li 2 O 3~15%, 0~10% of Na 2 O, 0 to 8% of K 2 O, 0% to MgO, CaO 0-3% 0-3% the SrO, 0-3% of BaO, ZnO and 0-10%, chemically strengthened glass containing ZrO 2 0 to 4%. ΔCS DOL-20 = CS DOL-20 / 20 [Selection figure] None |