Chemically temperable glass sheet
AssigneeAgc Glass Europe
InventorThomas Lambricht
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Abstract
The invention relates to a 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≤4% 0≤CaO<4.5% 4≤MgO≤12%; as well as a (CaO/MgO) ratio which is less than 1. 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.
Claims20
A 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%;
- 2≤Al2O3≤3%;
- 0≤CaO <4.5%;
- and
- 4≤MgO ≤12%;
- wherein the glass sheet has a (CaO/MgO) ratio which is less than 1,
- wherein the glass sheet has been chemically tempered, and
- wherein the glass sheet has a melting point temperature of 1550° C. or lower.
A chemically tempered 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≤4%;
- 0≤CaO ≤4.5%;
- and
- 4≤MgO ≤12%;
- wherein the glass sheet has a (CaO/MgO) ratio which is less than 1, and
- wherein the glass sheet has a melting point temperature of 1550° C. or lower.
Dependencies are inferred from the claim text.