Patent US4668489A successfully refreshed from Google Patents.
Patent US2632687A successfully refreshed from Google Patents.
US2632687A
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Preparation of calcium cyanamide
Assignee: Monsanto Chemicals Ltd
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Filing: 1948-09-30
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Granted: 1953-03-24
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Expires: 1968-09-30
Abstract
No abstract record available.
Inventors
- 👤 Henry A Walter
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 23:00
CPC Classifications
C; C01; C01C; C01C3/00; C01C3/16; C01C3/18
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
78 words
A PROCESS FOR THE PREPARATION OF CALCIUM CYANAMIDE WHICH CONSISTS OF REACTING 100 PARTS OF CALCIUM OXIDE WITH FROM 120 TO 350 PARTS OF UREA IS ADMIXTURE WITH FROM 11 TO 110 PARTS OF CALCIUM CHLORIDE AT TEMPERATURES RANGING FROM 1000* F. TO 2000* F. FOR A PERIOD OF TIME RANGING FROM 15 MINUTES AT 2000* F. TO 90 MINUTES AT 1000* F., ALL OF THE INITIAL REACTANTS BEING IN SUBSTANTIALLY ANHYDROUS CONDITION, AND RECOVERING SOLID CALCIUM CYANAMIDE.
Claim 2
Dependent Claim
78 words
A PROCESS FOR THE PREPARATION OF CALCIUM CYANAMIDE WHICH CONSISTS OF REACTING 100 PARTS OF CALCIUM OXIDE WITH FROM 120 TO 350 PARTS OF UREA IS ADMIXTURE WITH FROM 11 TO 110 PARTS OF CALCIUM CHLORIDE AT TEMPERATURES RANGING FROM 1000* F. TO 2000* F. FOR A PERIOD OF TIME RANGING FROM 15 MINUTES AT 2000* F. TO 90 MINUTES AT 1000* F., ALL OF THE INITIAL REACTANTS BEING IN SUBSTANTIALLY ANHYDROUS CONDITION, AND RECOVERING SOLID CALCIUM CYANAMIDE.
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) | 1956-03-23 | 1956-09-22 | 1957-03-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1960-03-23 | 1960-09-22 | 1961-03-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1964-03-23 | 1964-09-22 | 1965-03-24 | $7700.00 | Window Closed / Lapsed |