Patent US3579463A successfully refreshed from Google Patents.
US3579463A
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Method of preparing crystalline calcium halophosphate phosphor
Assignee: Philips North America LLC
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Filing: 1969-05-07
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Granted: 1971-05-18
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Expires: 1989-05-07
Abstract
Abstract METHOD OF PREPARING CRYSTALLINE CALCIUM HALOPHOSPHATE OF A PARTICLE SAIZE DISTRIBUTION WHICH CAN BE ADVANTAGEOUSLY USED IN COMMERCIAL FLUORESCENT LAMPS. A RAW MIX IS PREPARED OF THE CONSTITUENTS REQUIRED TO FORM THE CALCIUM HALOPHOSPHATE CONSTITUENTS IN PREDETERMINED AMOUNTS. THE FIRING IS CARRIED OUT AT A PREDETERMINED TEMPERATURE AND TIME TO FORM THE HALOPHOSPHATE MATRIX HAVING THE DESIRED CRYSTALLINITY AND PARTICLE SIZE DISTRIBUTION. THEN, A SELECTED AMOUNT OF ACTIVATOR CONSTITUENT IS MIXED WITH THE HALOPHOSPHATE MATRIX AND IS INCORPORATED INTO THE MATRIX DURING A SUBSEQUENT FIRING TO FORM THE PHOSPHOR.
Inventors
- 👤 Anselm Wachtel
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 07:18
CPC Classifications
C; C01; C01B; C01B25/00; C01B25/16; C01B25/26; C01B25/455; C09; C09K; C09K11/00; C09K11/08; C09K11/0855; C09K11/0861; C09K11/0866
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-05-17 | 1974-11-16 | 1975-05-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-05-17 | 1978-11-16 | 1979-05-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-05-17 | 1982-11-16 | 1983-05-18 | $7700.00 | Window Closed / Lapsed |