Chemically resistant glass
A glass is disclosed that is particularly suitable as pharmaceutical packing medium and as a chemically pre-stressable glass comprising at least the following components (in mol-% on oxide basis): 64-77 SiO 2 , 5-14 Al 2 O 3 , 4-12 Na 2 O, 1-12 CaO, 0-14 MgO, 0 -2 ZrO 2 , 0-4.5 TiO 2 , wherein the ratio Al 2 O 3 /Na 2 O≥1, wherein the ratio Al 2 O 3 /CaO≥1.5, and wherein the total content SiO 2 +Al 2 O 3 <82 mol-%. Preferably, a working temperature T4 of less than 1350° C. and a hydrolytic resistance according to DIN ISO 719 HGB1 and according to ISO 720 HGA are obtained.
1. A glass comprising at least the following components (given in mol-% on oxide basis):
SiO 2
64-77
Al 2 O 3
5-14
Na 2 O
4-12
CaO
1-12
MgO
0-14
ZrO 2
0-2
TiO 2
0-4.5;
wherein the ratio Al 2 O 3 /Na 2 O≥1 and ≤3;
wherein the ratio Al 2 O 3 /CaO≥1.5 and ≤5.2;
wherein the total content SiO 2 +Al 2 O 3 <82 mol-%;
wherein the content of K 2 O is >0.5 mol-%; and
wherein the glass has a working temperature of less than 1350° C.
2. The glass of claim 1 , which does not contain B 2 O 3 , apart from unavoidable contaminations.
3. The glass of claim 1 , wherein the content of K 2 O is a maximum of 3 mol-%.
4. The glass of claim 1 , further comprising up to 3.5 mol-% SrO.
5. The glass of claim 1 , further comprising at least 0.1 mol-% of SrO.
6. The glass of any of the preceding claims, wherein the total content SiO 2 +Al 2 O 3 +ZrO 2 <82 mol-%.
7. The glass of claim 1 , wherein the Al 2 O 3 content is at least 9 mol-%.
8. The glass of claim 1 , comprising up to 3 mol-% of Li 2 O.
9. The glass of claim 1 , which does not contain ZnO, apart from unavoidable impurities.
10. The glass of claim 1 , wherein the content of magnesium oxide is a maximum of 4 mol-%.
11. The glass of claim 1 , wherein the hydrolytic resistance according to DIN ISO 719 is HGB 1.
12. The glass of claim 1 , wherein the hydrolytic resistance according to DIN ISO 720 is HGA1.
13. The glass of claim 1 , further comprising at least 0.1 mol-% of ZrO 2 .
14. The glass of claim 1 , further comprising at least 0.1 mol-% of TiO 2 .
15. The glass of claim 1 , further comprising 0.5 mol-% to 1.5 mol-% of TiO 2 .
16. The glass of claim 1 , wherein the total content of ZrO 2 +TiO 2 is at least 0.1 mol-%.
17. The glass of claim 1 , wherein the total content of ZrO 2 +TiO 2 is a maximum of 4.5 mol-%.
18. A glass container made of a glass according to claim 1 , being chemically pre-stressed by means of ion-exchange, comprising a compressive stress layer with a layer depth of at least 10 μm and a compressive stress of at least 500 MPa.
19. A glass comprising at least the following components (given in mol-% on oxide basis):
SiO 2
64-77
Al 2 O 3
5-14
Na 2 O
4-12
CaO
1-12
MgO
0-14
ZrO 2
0-2
TiO 2
0-4.5;
wherein the ratio Al 2 O 3 /Na 2 O≥1 and ≤3;
wherein the ratio Al 2 O 3 /CaO≥1.5 and ≤5.2;
wherein the total content SiO 2 +Al 2 O 3 <82 mol-%; and
wherein the glass has a hydrolytic resistance according to DIN ISO 719 that is HGB 1 and/or according to DIN ISO 720 that is HGA1.