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US3449258A
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US
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Method for preparing europium activated yttrium oxide and gadolinium oxide phosphors
Assignee: Philips North America LLC
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Filing: 1965-07-22
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Granted: 1969-06-10
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Expires: 1985-07-22
Abstract
No abstract record available.
Inventors
- 👤 Richard C Ropp
- 👤 Edward E Gritz
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 17:36
CPC Classifications
C; C09; C09K; C09K11/00; C09K11/08; C09K11/77; C09K11/7783; C09K11/7784; C09K11/7787
Claims Analysis
Total Claims: 0
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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) | 1972-06-09 | 1972-12-09 | 1973-06-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1976-06-09 | 1976-12-09 | 1977-06-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1980-06-09 | 1980-12-09 | 1981-06-10 | $7700.00 | Window Closed / Lapsed |