Glass sheet capable of having controlled warping through chemical strengthening

Abstract

The invention relates to a float glass sheet having a boron- and lithium-free glass composition comprising the following in weight percentage, expressed with respect to the total weight of glass: 65≤SiO2≤78% 5≤Na2O≤20% 0≤K2O<5% 1≤Al2O3<6% 0≤CaO<4.5% 4≤MgO≤12% a (MgO/(MgO+CaO)) ratio≥0.5 characterized in that the glass sheet has: (I). The invention corresponds to an easy chemically-temperable soda-silica type glass composition, which is more suited for mass production than aluminosilicate glass, and therefore is available at low cost, and with a base glass/matrix composition that is close to or very similar to compositions already used in existing mass production, and finally which shows reduced or controlled increased warping effect.

Dependencies are inferred from the claim text.