US3607744A
Expired / Lapsed
US
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Preparation of fire-extinguishing material comprising heating a mixture of urea and an alkali metal bicarbonate carbonate sesquicarbonate or hydroxide
Assignee: Imperial Chemical Industries Ltd
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Filing: 1969-02-03
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Granted: 1971-09-21
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Expires: 1989-02-03
Abstract
Abstract Improved yields of fire-extinguishing compounds having the empirical formula MC2N2H3O3 where M is Na or K, and made by heating urea with carbonates, bicarbonates, sesquicarbonates or hydroxides of sodium or potassium at temperatures below 150* C., are obtained by having water vapor present in the atmosphere in contact with the reaction system. The preferred proportion of water vapor is 15% to 35% by volume and the preferred reaction temperature 120* C. to 140* C.
Inventors
- 👤 Arnold George Cottrell
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 14:08
CPC Classifications
A; A62; A62D; A62D1/00; A62D1/0007; A62D1/0014
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
30 words
A process as claimed in claim 1 in which the alkali is selected from sodium carbonate and potassium carbonate and the reaction temperature is from 120* C. to 140* C.
Claim 2
Dependent Claim
34 words
A process as claimed in claim 2 in which the percentage by volume of water vapor in the atmosphere in contact with the reaction mixture of urea and alkali is from 20 to 35.
Claim 3
Dependent Claim
29 words
A process as claimed in claim 1 in which the alkali is selected from sodium bicarbonate and potassium bicarbonate and the reaction temperature is 120* C. to 140* C.
Claim 4
Dependent Claim
33 words
A process as claimed in claim 4 in which the percentage by volume of water vapor in the atmosphere in contact with the reaction mixture of urea and alkali is 15 to 30.
Claim 5
Dependent Claim
76 words
A process as claimed in claim 1 in which the alkali is potassium carbonate, and the reaction temperature is 120* C. to 140* C., and the percentage by volume of water vapor in the atmosphere in contact with the reaction mixture of urea and potassium carbonate is from 15 to 25, and to said reaction mixture is added from 1% to 10% by weight of water before the mixture is heated to the said reaction temperature.
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) | 1974-09-20 | 1975-03-22 | 1975-09-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-09-20 | 1979-03-22 | 1979-09-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-09-20 | 1983-03-22 | 1983-09-21 | $7700.00 | Window Closed / Lapsed |