Method of preparing a luminescent quartz glass activated by bivalent europium, luminescent quartz glass obtained by such a method and luminescent screen provided with such a luminescent quartz glass
US4814105A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 7, 1987 |
| Grant date | Mar 21, 1989 |
| Priority date | — |
| Expiry date | Oct 7, 2007 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC03C4/18
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
Method of preparing an aluminum oxide containing quartz glass activated by bivalent europium and comprising as glass matrix oxides mainly SiO.sub.2 and furthermore per mol of SiO.sub.2 up to at most 0.15 mol of at least one of the oxides, Al.sub.2 O.sub.3, B.sub.2 O.sub.3, P.sub.2 O.sub.5, ZrO.sub.2, Scf.sub.2 O.sub.3, Y.sub.2 O.sub.3, La.sub.2 O.sub.3, Gd.sub.2 O.sub.3, Lu.sub.2 O.sub.3, the alkali metal oxides and the alkaline earth metal oxides. A mixture is made of the composite oxides or of compounds which yield these oxides. The mixture comprises europium in the form of an aluminum containing compound of bivalent europium. The mixture is melted at a high temperature in a reducing atmosphere and is then cooled. The luminescent quartz glasses obtained are used in luminescent screens of, for example, low-pressure mercury vapor discharge lamps.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.