Alkaline-earth aluminosilicate glass, containing CA and BA, suitable for use in lamp bulbs, and a lamp bulb containing same
An alkaline-earth aluminosilicate glass having a composition (in % by weight, based on oxide) of SiO 2 >55-64; Al 2 O 3 13-18; B 2 O 3 0-5.5; M 5 O 0-7; CaO 5.5-14; SrO 0-8; BaO 6-17; ZrO 2 0-2; CeO 2 0-0.3; TiO 2 0-0.5; CoO 0.01-0.035; Fe 2 O 3 0.005-0.05; and NiO 0-0.03 is suitable for use in lamp bulbs
1. An alkaline-earth aluminosilicate glass for lamp bulbs, having a composition (in % by weight, based on oxide) comprising:
SiO 2
>55-64
Al 2 O 3
13-18
B 2 O 3
0-5.5
MgO
0-7
CaO
5-14
SrO
0-8
BaO
6-17
ZrO 2
0-2
CeO 2
0-0.3
TiO 2
0-0.5
CoO
0.01-0.035
Fe 2 O 3
0.005-0.05.
2. An alkaline-earth aluminosilicate glass as claimed in claim 1 , comprising (in % by weight, based on oxide):
SiO 2
>58-62
Al 2 O 3
13.5-17.5
B 2 O 3
0-5.5
MgO
0-7
CaO
5.5-14
SrO
0-8
BaO
6-10
ZrO 2
0-2
CeO 2
0-0.3
TiO 2
0-0.5
CoO
0.01-0.035
Fe 2 O 3
0.005-0.05.
3. An alkaline-earth aluminosilicate glass as claimed in claim 1 , comprising (in % by weight, based on oxide):
SiO 2
59-62
Al 2 O 3
13.5-15.5
B 2 O 3
3-5.5
MgO
2.5-5
CaO
8.2-10.5
BaO
8.5-9.5
ZrO 2
0-1
TiO 2
0-0.5
CoO
0.01-0.035
Fe 2 O 3
0.005-0.05.
4. An alkaline-earth aluminosilicate glass as claimed in claim 1 , comprising (in % by weight, based on oxide):
SiO 2
>58-62
Al 2 O 3
14-17.5
B 2 O 3
0-1
MgO
0-7
CaO
5.5-14
SrO
0-8
BaO
6-17
ZrO 2
0-2
CeO 2
0-0.3
TiO 2
0-0.5
CoO
0.01-0.035
Fe 2 O 3
0.005-0.05.
5. An alkaline-earth aluminosilicate glass as claimed in claim 1 , comprising (in % by weight, based on oxide):
SiO 2
>58-62
Al 2 O 3
15-17.5
B 2 O 3
0-0.7
MgO
0-7
CaO
5.5-14
SrO
0-8
BaO
6-10
ZrO 2
0-2
CeO 2
0-0.3
TiO 2
0-0.5
CoO
0.01-0.035
Fe 2 O 3
0.005-0.05.
6. An alkaline-earth aluminosilicate glass as claimed in claim 1 , further comprising up to 0.03% by weight of NiO.
7. An alkaline-earth aluminosilicate glass as claimed in claim 2 , further comprising up to 0.03% by weight of NiO.
8. An alkaline-earth aluminosilicate glass as claimed in claim 3 , further comprising up to 0.03% by weight of NiO.
9. An alkaline-earth aluminosilicate glass as claimed in claim 4 , further comprising up to 0.03% by weight of NiO.
10. An alkaline-earth aluminosilicate glass as claimed in claim 5 , further comprising up to 0.03% by weight of NiO.
11. An alkaline-earth aluminosilicate glass as claimed in claim 1 , containing 0.02-0.03% by weight of CoO.
12. An alkaline-earth aluminosilicate glass as claimed in claim 1 , containing 0.015-0.03% by weight of Fe 2 O 3 .
13. An alkaline-earth aluminosilicate glass as claimed in claim 11 , containing 0.015-0.03% by weight of Fe 2 O 3 .
14. An alkaline-earth aluminosilicate glass as claimed in claim 1 , wherein said glass has a coefficient of thermal expansion α 20/300 of 4.3×10 −6 /K-4.95×10 −6 /K, a transformation temperature T g of more than 700° C.
15. In a lamp bulb made from a glass, the improvement wherein said glass is as claimed in claim 1 .
16. In a lamp bulb made from a glass, the improvement wherein said glass is as claimed in claim 14 .
17. A lamp bulb according to claim 15 , wherein said lamp is a halogen lamp.
18. A lamp bulb according to claim 16 , wherein said lamp is a halogen lamp.
19. A halogen lamp having a lamp bulb made from a glass as claimed in claim 1 , having a color temperature of ≧3 400 K.
20. A halogen lamp according to claim 19 , wherein said glass has a color temperature of ≧3 600 K.