Patent US3659093A successfully refreshed from Google Patents.
US3353907A
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Method for producing rare earth chalcogenides
Assignee: International Business Machines Corp
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Filing: 1964-10-02
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Granted: 1967-11-21
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Expires: 1984-10-02
Abstract
No abstract record available.
Inventors
- 👤 Merrill W Shafer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 06:12
CPC Classifications
C; C01; C01B; C01B19/00; C01B19/007; C01F; C01F17/00; C01F17/20; C01F17/288; H; H01; H01F; H01F1/00; H01F1/01; H01F1/03; H01F1/0302; H01F1/0311
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
77 words
A METHOD OF PREPARING EUROPIUM (II) CHALCOGENIDE COMPOUNDS COMPRISING THE STEPS OF: (A) DISSOLVING ELEMENTAL EUROPIUM AND A CHALCOGEN SELECTED FROM THE GROUP CONSISTING OF SULFUR AND SELENIUM IN LIQUID AMMONIA, (B) HEATING THE LIQUID AMMONIA SOLUTION TO A TEMPERATURE OF ABOUT THE BOILING POINT OF SAID LIQUID AMMONIA TO PRECIPITATE SAID EUROPIUM (II) CHALCOGENIDE COMPOUND, AND (C) DRYING THE PRECIPITATE BY HEATING SAID PRECIPITATE IN AN OXYGEN AND MOISTURE FREE ATMOSPHERE AND COOLING SAID DRIED PRECIPITATE.
Claim 2
Independent Claim
77 words
A METHOD OF PREPARING EUROPIUM (II) CHALCOGENIDE COMPOUNDS COMPRISING THE STEPS OF: (A) DISSOLVING ELEMENTAL EUROPIUM AND A CHALCOGEN SELECTED FROM THE GROUP CONSISTING OF SULFUR AND SELENIUM IN LIQUID AMMONIA, (B) HEATING THE LIQUID AMMONIA SOLUTION TO A TEMPERATURE OF ABOUT THE BOILING POINT OF SAID LIQUID AMMONIA TO PRECIPITATE SAID EUROPIUM (II) CHALCOGENIDE COMPOUND, AND (C) DRYING THE PRECIPITATE BY HEATING SAID PRECIPITATE IN AN OXYGEN AND MOISTURE FREE ATMOSPHERE AND COOLING SAID DRIED PRECIPITATE.
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) | 1970-11-20 | 1971-05-22 | 1971-11-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1974-11-20 | 1975-05-22 | 1975-11-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1978-11-20 | 1979-05-22 | 1979-11-21 | $7700.00 | Window Closed / Lapsed |