US 12,006,255 B2
Lithium containing aluminosilicate glass with low expansion after chemical toughening
Junming Xue, Shanghai (CN); Feng He, Jiangsu (CN); Jose Zimmer, Eppstein (DE); and Ning Da, Jiangsu (CN)
Assigned to SCHOTT Glass Technologies (Suzhou) Co. Ltd., Jiangsu (CN)
Filed by SCHOTT Glass Technologies (Suzhou) Co. Ltd., Jiangsu (CN)
Filed on Aug. 27, 2019, as Appl. No. 16/552,326.
Application 16/552,326 is a continuation of application No. PCT/CN2017/075041, filed on Feb. 27, 2017.
Prior Publication US 2019/0382302 A1, Dec. 19, 2019
Int. Cl. C03C 3/083 (2006.01); C03C 3/078 (2006.01); C03C 3/089 (2006.01); C03C 3/097 (2006.01)
CPC C03C 3/083 (2013.01) [C03C 3/078 (2013.01); C03C 3/089 (2013.01); C03C 3/097 (2013.01); C03C 2203/50 (2013.01)] 23 Claims
OG exemplary drawing
 
1. A chemically toughenable or toughened glass having before chemical toughening a thickness t of less than or equal to 500 μm, the glass comprising the following components in mol-%:
SiO2 45-75;
Al2O3 12-25;
Li2O >1-11;
P2O5 0-15;
B2O3 0-8;
TiO2 0-5; and
Na2O in an amount of at least 3 mol-%;
wherein an 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 and wherein upon chemical toughening a linear dimension variation in the unit of percentage V1 is so low that an overall geometry variation OGV calculated as (DoL/O/V1 is higher than 0.8, wherein DoL is a total depth of all ion-exchange layers on one side of the glass and wherein DoL is from >3 μm to <0.5*t when the glass is chemically toughened with NaNO3 only, KNO3 only, or with both KNO3 and NaNO3, wherein a molar ratio of Li2O/(Li2O+Na2O+K2O) is larger than 0.20.