Patent US4638425A successfully refreshed from Google Patents.
US2597631A
Expired / Lapsed
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Method of preparing barium silicate phosphor
Assignee: General Electric Co
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Filing: 1950-03-22
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Granted: 1952-05-20
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Expires: 1970-03-22
Abstract
No abstract record available.
Inventors
- 👤 Herman C Froelich
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 16:10
CPC Classifications
C; C09; C09K; C09K11/00; C09K11/08; C09K11/66; C09K11/666
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
125 words
THE METHOD OF PREPARING A FLUORESCENT COMPOSITION OF LEAD ACTIVATED BARIUM DISILICATE WHICH COMPRISES MIXING COMPOUNDS OF BARIUM AND SILICON WHICH UPON HEATING WILL REACT TO FORM BARIUM DISILICATE WITH AN ACTIVATING PROPORTION OF A LEAD COMPOUND, AND FIRING THE MIXTURE AT A TEMPERATURE OF APPROXIMATELY 1000-1200* C. WITH ADDITIONS OF CATALYST CONSISTING OF BOTH A FLUORIDE AND A CHLORIDE, THE FLUORIDE BEING OF THE GROUP CONSISTING OF FLUORIDES OF BARIUM, AMMONIUM, LEAD AND CALCIUM, AND THE CHLORIDE BEING OF THE GROUP CONSISTING OF CHLORIDES OF BARIUM, AMMONIUM, CALCIUM, STRONTIUM, MAGNESIUM, ALUMINUM AND ZINC, THE SAID CATALYSTS BEING IN A TOTAL AMOUNT OF ABOUT 2-12 MOL PER CENT OF THE BARIUM DISILICATE WITH A MOL RATIO OF FLUORINE TO CHLORINE BETWEEN ABOUT 0.2:2 AND 2:0.2.
Claim 2
Independent Claim
125 words
THE METHOD OF PREPARING A FLUORESCENT COMPOSITION OF LEAD ACTIVATED BARIUM DISILICATE WHICH COMPRISES MIXING COMPOUNDS OF BARIUM AND SILICON WHICH UPON HEATING WILL REACT TO FORM BARIUM DISILICATE WITH AN ACTIVATING PROPORTION OF A LEAD COMPOUND, AND FIRING THE MIXTURE AT A TEMPERATURE OF APPROXIMATELY 1000-1200* C. WITH ADDITIONS OF CATALYST CONSISTING OF BOTH A FLUORIDE AND A CHLORIDE, THE FLUORIDE BEING OF THE GROUP CONSISTING OF FLUORIDES OF BARIUM, AMMONIUM, LEAD AND CALCIUM, AND THE CHLORIDE BEING OF THE GROUP CONSISTING OF CHLORIDES OF BARIUM, AMMONIUM, CALCIUM, STRONTIUM, MAGNESIUM, ALUMINUM AND ZINC, THE SAID CATALYSTS BEING IN A TOTAL AMOUNT OF ABOUT 2-12 MOL PER CENT OF THE BARIUM DISILICATE WITH A MOL RATIO OF FLUORINE TO CHLORINE BETWEEN ABOUT 0.2:2 AND 2:0.2.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1955-05-20 | 1955-11-19 | 1956-05-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1959-05-20 | 1959-11-19 | 1960-05-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1963-05-20 | 1963-11-19 | 1964-05-20 | $7700.00 | Window Closed / Lapsed |