US3574130A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Europium activated rare earth phosphors containing trivalent cerium brightness control
Assignee: GTE Sylvania Inc
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Filing: 1969-01-16
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Granted: 1971-04-06
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Expires: 1989-01-16
Abstract
Abstract AN IMPROVED PROCESS FOR THE MANUFACTURE OF EUROPIUMACTIVATED RARE EARTH OXIDE PHOSPHORS, EUROPIUM-ACTIVATED RARE EARTH PHOSPHORS DERIVED FROM RARE EARTH OXIDES AND MIXTURES THEREOF AND THE IMPROVED PHOSPHORS ARE DISCLOSED. THE IMPROVEMENT COMPRISES CONTROLLING THE BRIGHTNESS OF THE PHOSPHOR BY INCORPORATING A CONTROLLED AMOUNT OF CERIUM INTO THE EUROPIUM-ACTIVATED RARE EARTH OXIDE AT THE TIME OF SYNTHESIS OF THE EUROPIUM-ACTIVATED RARE EARTH OXIDE.
Inventors
- 👤 James E Mathers
- 👤 Emil J Mehalchick
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 09:47
CPC Classifications
C; C09; C09K; C09K11/00; C09K11/08; C09K11/77; C09K11/7783; C09K11/7794; C09K11/7784; C09K11/7787; C09K11/7789
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-04-05 | 1974-10-05 | 1975-04-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-04-05 | 1978-10-05 | 1979-04-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-04-05 | 1982-10-05 | 1983-04-06 | $7700.00 | Window Closed / Lapsed |