Patent ID: 12006255

Abstract:
A chemically toughenable or toughened glass has, before chemical toughening, a thickness t of at most 1100 μm. The glass comprises the following components: 45-75 mol-% SiO2; 10-25 mol-% Al2O3; >1-11 mol-% Li2O; 0-15 mol-% P2O5; 0-8 mol-% B2O3; and 0-5 mol-% TiO2. The average number of bridging oxygen per polyhedron (BO) calculated as 2*4−2*(cmol(O)/(cmol(Si)+cmol(Al)+cmol(B)+cmol(P)+cmol(Ti))) is higher than 3.55. Upon chemical toughening, the linear dimension variation in the unit of percentage (V1) is so low that the overall geometry variation (OGV) calculated as (DoL/t)/V1 is higher than 0.8. DoL is the total depth of all ion-exchange layers on one side of the glass and DoL is more than 1 μm, when the glass is chemically toughened with NaNO3 only, KNO3 only or with both KNO3 and NaNO3.