Corning Incorporated
ION EXCHANGEABLE ALKALI ALUMINOSILICATE GLASS COMPOSITIONS HAVING IMPROVED MECHANICAL DURABILITY

Abstract:

A glass composition comprises: 50.0 mol % to 70.0 mol % SiO.sub.2; 10.0 mol % to 25.0 mol % Al.sub.2O.sub.3; 0.0 mol % to 5.0 mol % P.sub.2O.sub.3; 0.0 mol % to 10.0 mol % B.sub.2O.sub.3; 5.0 mol % to 15.0 mol % Li.sub.2O; 1.0 mol % to 15.0 mol % Na.sub.2O; and 0.0 mol % to 1.0 mol % K.sub.2O. The sum of all alkali oxides, R.sub.2O, present in the glass composition may be in the range from greater than or equal to 11.0 mol % to less than or equal to 23.0 mol %. The sum of Al.sub.2O.sub.3 and R.sub.2O present in the glass composition may be in the range from greater than or equal to 26.0 mol % to less than or equal to 40.0 mol %. The glass composition may satisfy the relationship -0.1.ltoreq.(Al.sub.2O.sub.3--(R.sub.2O+RO))/Li.sub.2O.ltoreq.0.3.