Patent · US Expired

Lead oxide-free glass, particularly for use in electric lamps

US5180695A · kind A · utility

2Cited by

7References

14Claims

0Family size

Assignee

Patent-Treuhand-Gesellschaft fur elektrische Gluhlampen mbH · DE

Inventors

Werner Weiss · Stadtbergen, DE
Manfred Mair · Augsburg, DE
Manfred Deisenhofer · Burgau, DE
Ewald Poesl · Kissing, DE

Key dates

Filing date	Jun 10, 1991
Grant date	Jan 19, 1993
Priority date	—
Expiry date	Jun 10, 2011

Classification

Technology area (CPC C)Chemistry; Metallurgy
CPC primaryC03C8/24
WIPO fieldMaterials, metallurgy
WIPO sectorChemistry

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: PA1 SiO.sub.2 40-60% PA1 Al.sub.2 O.sub.3 2-5% PA1 CaO 5-10% PA1 BaO 20-30% PA1 V.sub.2 O.sub.5 2-5% PA1 K.sub.2 O 5-7% PA1 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%.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.