Abstract: Glazing, thermally tempered to required standards, are produced more readily by tempering panes having a high coefficient of thermal expansion (greater than 93×10−7 per degree Centigrade) and for a low Fracture Toughness (less than 0.72 MPam1/2). Use of glasses selected according to the invention enables thin glazings (especially glazings less than 3 mm thick) to be tempered to automotive standard with improved yields using conventional tempering methods, and thicker glazings to be tempered at lower quench pressure than required hitherto. Suitable glasses include glasses comprising, in percentages by weight, 64 to 75%, SiO2, 0 to 5% Al2O3, 0 to 5% B2O3, 9 to 16% alkaline earth metal oxide other than MgO, 0 to 2% MgO, 15 to 18% alkali metal oxide and at least 0.05% total iron (calculated as Fe2O3).

Abstract: Glazing, thermally tempered to required standards, are produced more readily by tempering panes having a high coefficient of thermal expansion (greater than 93×10−7 per degree Centigrade) and for a low Fracture Toughness (less than 0.72 MPam½). Use of glasses selected according to the invention enables thin glazings (especially glazings less than 3 mm thick) to be tempered to automotive standard with improved yields using conventional tempering methods, and thicker glazings to be tempered at lower quench pressure than required hitherto. Suitable glasses include glasses comprising, in percentages by weight, 64 to 75% SiO2, 0 to 5% Al2O3, 0 to 5% B2O3, 9 to 16% alkaline earth metal oxide other than MgO, 0 to 2% MgO, 15 to 18% alkali mental oxide and at least 0.

Abstract: A high performance green glass composition containing at least 14.5% by weight Na2O, at least 10.5% by weight CaO, at least 0.5% by weight total iron (measured as Fe2O3) and is substantially magnesium-free, the glass thus produced having a ferrous value of at least 30% and a performance (light transmission minus Direct Solar Heat Transmission) of at least 28% at at least one thickness of 2.8 mm to 5 mm. The invention also relates to glasses made from such composition and to a laminated glass assembly in which two sheets of glass sandwich a polymeric material, at least one, preferably both, of the sheets of glass having such a composition.