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US3282855A Expired / Lapsed US ⏱️ 0.0 years remaining

Method of making thermoluminescent manganese-activated calcium fluoride

Assignee: Revvity Inc
•
Filing: 1965-08-02
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Granted: 1966-11-01
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Expires: 1985-08-02
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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 23:10
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

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