Safety strengthened glass with tensile stress area with low variation amplitude, and preparation method and application thereof

A chemically strengthened glass, having a front surface and a back surface and wherein a thickness T between the front surface and the back surface is within a range of 0.45-0.85 mm, and wherein stress distribution of the chemically strengthened glass meets following conditions:

• the chemically strengthened glass having stress distribution with the following characteristics:
• the chemically strengthened glass comprising a first stress region and a second stress region, wherein the first stress region is a compressive stress region, the second stress region is a tensile stress region,
• wherein DOL-0 is the depth at which the compressive stress is 0, DOL-0-1 is the depth at which the compressive stress is 0 from a front surface, DOL-0-2 is the depth at which the compressive stress is 0 from a back surface;
• wherein the ratio between DOL-0 and the total thickness of the glass shall not be less than 17%;
• wherein CS-30 of the chemically strengthened glass meets the following formula, CS-30=a*exp(−T/b)+c, wherein CS-30 is compressive stress of the depth of 30 micrometers distant from the surface of the strengthened glass;
• a is −485;
• b is 0.5;
• c is 278+(+40/T2 or −40 T2);
• T is the thickness of the strengthened glass, and the unit is mm;
• wherein the glass is prepared by using raw materials comprising oxides at following proportions in mol %:
• Composition
• mol %
• SiO2
• 55%-75%
• Al2O3
• 8%-22%
• B2O3
• 0%-5%
• P2O3
• 0%-5%
• MgO
• 1%-8%
• ZnO
• 0-2%
• ZrO2
• 0-2%
• TiO2
• 0-2%
• Na20
• 0%-5%
• Li2O
• 4%-13%
• K2O
• 0-5%
• SnO2
• 0.1%-2%.