High alumina low soda glass compositions
A glass composition includes a base glass portion comprising: 65-75 wt % SiO 2 ; 5-15 wt % CaO; 0-5 wt % MgO; 0-5 wt % K 2 O; 10-14 wt % Na 2 O; and 1-5 wt % Al 2 O 3 ; wherein the glass composition has a ratio of Na 2 O to Al 2 O 3 is in the range of 9.5-12.5 wt %/wt %.
1. A glass composition comprising a base glass portion comprising:
65-75 wt % SiO 2 ;
5-15 wt % CaO;
0-5 wt % MgO;
0.1-0.5 wt % K 2 O;
10-14 wt % Na 2 O; and
1-1.47 wt % Al 2 O 3 ;
wherein the glass composition has a weight ratio of Na 2 O to Al 2 O 3 is in the range of 9.5-12.
2. The glass composition of claim 1 , wherein the base glass portion has a weight ratio of CaO to MgO in the range of 1.5-2.2.
3. The glass composition of claim 1 , wherein the base glass portion comprises 0.2-0.4 wt % K 2 O.
4. The glass composition of claim 1 , wherein the base glass portion comprises:
68-74 wt % SiO 2 ;
13-13.5 wt % Na 2 O;
1-1.4 wt % Al 2 O 3 ;
8.1-8.6 wt % CaO; and
4.5-5 wt % MgO.
5. The glass composition of claim 1 , wherein the total iron in the glass composition is in the range of 0.01 to 0.30 wt %.
6. The glass composition of claim 1 , further comprising a colorant portion, the colorant portion comprising:
CoO in an amount ranging from 30 to 120 ppm; or
Se in an amount no greater than 7.5 ppm.
7. The glass composition of claim 1 , wherein the glass composition, when formed as a glass sheet, has a color described by the following chromaticity coordinates: an a* ranging from −4 to +4 and a b* ranging from 0 to −20.
8. The glass composition of claim 1 , wherein the glass composition, when formed as a glass sheet, has a visible light transmittance of no greater than 80%.
9. The glass composition of claim 1 , wherein the total iron in the glass composition is in the range of 0.2 to 0.8 wt %.
10. The glass composition of claim 1 , wherein the glass composition has a redox ratio in the range of 0.4-0.6.
11. The glass composition of claim 1 , further comprising a colorant portion comprising: CoO in an amount no greater than 20 ppm; or Se in an amount no greater than 3 ppm.
12. The glass composition of claim 1 , wherein the glass composition, when formed as a glass sheet, has a color described by the following chromaticity coordinates: an a* ranging from −8 to −16 and a b* ranging from +3 to −17.
13. The glass composition of claim 1 , further comprising a colorant portion comprising at least one of the following: oxides of manganese, tin, cerium, molybdenum, vanadium, copper, zinc, tungsten, and lanthanum, or any combination thereof.
14. The glass composition of claim 1 further comprising 0.16-0.18 wt. % Fe 2 O 3 .
15. The glass composition of claim 1 further comprising 0.49-0.58 wt. % Fe 2 O 3 .
16. A glass composition comprising a base glass portion comprising:
SiO 2 71.2-71.6 wt. %;
CaO 8.3-8.6 wt. %;
MgO 5.0-5.2 wt. %;
K 2 O 0.24-0.25 wt. %;
Na 2 O 13.4-13.5 wt. %; and
Al 2 O 3 1.1-1.2 wt. %.
17. The glass composition of claim 16 further comprising 0.20-0.21 wt. % Fe 2 O 3 .
18. The glass composition of claim 16 wherein the weight ratio of Na 2 O to Al 2 O 3 is 11.1 to 11.3.
19. The glass composition of claim 16 wherein the weight ratio of CaO to MgO is 1.7 to 1.9.
20. A glass composition comprising a base glass portion comprising:
65-75 wt % SiO 2 ;
5-15 wt % CaO;
0-5 wt % MgO;
0.1-0.5 wt % K 2 O; and,
wherein the glass composition comprises an amount of Na 2 O to Al 2 O 3 in a weight ratio in the range of 9.5-12.