Lead oxide-free glass, particularly for use in electric lamps
AssigneePatent-Treuhand-Gesellschaft fur elektrische Gluhlampen mbH
InventorsWerner Weiss, Manfred Mair, Manfred Deisenhofer, Ewald Poesl
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Abstract
A lead oxide free glass of high electrical resistance, easy workability, that is, low abrasive characteristics, and a thermal coefficient of expansion compatible with electrical current supply leads, has an electrical resistance of 10.sup.12 ohm cm at 250.degree. C., and, basically, the following composition: SiO.sub.2 40-60% Al.sub.2 O.sub.3 2-5% CaO 5-10% BaO 20-30% V.sub.2 O.sub.5 2-5% K.sub.2 O 5-7% B.sub.2 O.sub.3 0-5% and additives comprising at least one of MgO, B.sub.2 O.sub.3, each present between 0 and about 5%.
Claims14
A glass body, wherein the glass of the glass body has high electrical resistance,
- said glass body consisting essentially of
- SiO.sub.2 40-60%
- Al.sub.2 O.sub.3 2-5%
- CaO 5-10%
- BaO 20-30%
- V.sub.2 O.sub.5 2-5%
- K.sub.2 O 5-7%
- B.sub.2 O.sub.3 0-5%
- wherein all percentages are given by weight.
Lead oxide free glass, particularly for electrical apparatus, said glass consisting essentially of
- SiO.sub.2 40-60%
- Al.sub.2 O.sub.3 2-5%
- CaO 5-10%
- BaO 20-30%
- V.sub.2 O.sub.5 2-5%
- K.sub.2 O 5-7%
- B.sub.2 O.sub.3 0-5%
- and additives comprising at least one of MgO, B.sub.2 O.sub.3, each present between 0 and about 5%.
Dependencies are inferred from the claim text.