US3282855A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of making thermoluminescent manganese-activated calcium fluoride
Assignee: Revvity Inc
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Filing: 1965-08-02
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Granted: 1966-11-01
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Expires: 1985-08-02
Abstract
No abstract record available.
Inventors
- 👤 Richard C Palmer
- 👤 Vincent D Poirier
- 👤 Ernest F Blase
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 08:31
CPC Classifications
C; C09; C09K; C09K11/00; C09K11/08; C09K11/61; C09K11/615; C09K11/616
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
141 words
THE METHOD OF MAKING THERMOLUMINESCENT, MANGANESE-ACTIVATED CALCIUM FLUORIDE THAT COMPRISES: MIXING AN AQUEOUS SLURRY OF CALCIUM CARBONATE AND 1 TO 10 MOLE PERCENT OF MANGANOUS CARBONATE, SAID CARBONATES HAVING AT LEAST REAGENT GRADE PURITY, WITH A CONCENTRATED SOLUTION OF HYDROFLUORIC ACID TO PRODUCE A PRECIPITATE CONSISTING OF CALCIUM FLUORIDE HAVING MAGANESE IONS INTERMIXED IN THE CRYSTAL LATTICE THEREOF; WASHING THE PRECIPITATE SUFFICIENTLY TO REMOVE ALL HYDROFLUORIC ACID AND OTHER BYPRODUCTS OF THE REACTION; DRYING THE PRECIPITATE TO PRODUCE A POWDER OF CALCIUM FLUORIDE HAVING MANGANESE IONS INTERMIXED IN THE CRYSTAL LATTICE THEREOF; HEATING SAID POWDER IN A FLUSHING, DRY INERT GAS ATMOSPHERE AT A TEMPERATURE OF 900*C. TO 1250*C. FOR A TIME PERIOD OF 15 MINUTES TO 4 HOURS TO CONVERT SAID POWDER TO THEREMOLUMINESCENT, MANGANESE-ACTIVATED CALCIUM FLUORIDE; AND COOLING SAID MANGANESE-ACTIVATED CALCIUM FLUORIDE IN SAID FLUSHING, DRY INERT GAS ATMOSPHERE.
Claim 2
Independent Claim
141 words
THE METHOD OF MAKING THERMOLUMINESCENT, MANGANESE-ACTIVATED CALCIUM FLUORIDE THAT COMPRISES: MIXING AN AQUEOUS SLURRY OF CALCIUM CARBONATE AND 1 TO 10 MOLE PERCENT OF MANGANOUS CARBONATE, SAID CARBONATES HAVING AT LEAST REAGENT GRADE PURITY, WITH A CONCENTRATED SOLUTION OF HYDROFLUORIC ACID TO PRODUCE A PRECIPITATE CONSISTING OF CALCIUM FLUORIDE HAVING MAGANESE IONS INTERMIXED IN THE CRYSTAL LATTICE THEREOF; WASHING THE PRECIPITATE SUFFICIENTLY TO REMOVE ALL HYDROFLUORIC ACID AND OTHER BYPRODUCTS OF THE REACTION; DRYING THE PRECIPITATE TO PRODUCE A POWDER OF CALCIUM FLUORIDE HAVING MANGANESE IONS INTERMIXED IN THE CRYSTAL LATTICE THEREOF; HEATING SAID POWDER IN A FLUSHING, DRY INERT GAS ATMOSPHERE AT A TEMPERATURE OF 900*C. TO 1250*C. FOR A TIME PERIOD OF 15 MINUTES TO 4 HOURS TO CONVERT SAID POWDER TO THEREMOLUMINESCENT, MANGANESE-ACTIVATED CALCIUM FLUORIDE; AND COOLING SAID MANGANESE-ACTIVATED CALCIUM FLUORIDE IN SAID FLUSHING, DRY INERT GAS ATMOSPHERE.
References Cited (Backward Citations)
US2746933A
Cited
US2757144A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1969-10-31 | 1970-05-02 | 1970-11-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1973-10-31 | 1974-05-02 | 1974-11-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1977-10-31 | 1978-05-02 | 1978-11-01 | $7700.00 | Window Closed / Lapsed |