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Patent US3715464A successfully refreshed from Google Patents.
US3715464A
Expired / Lapsed
US
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High voltage hold-down circuit
Assignee: RCA Licensing Corp
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Filing: 1971-05-28
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Granted: 1973-02-06
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Expires: 1991-05-28
Abstract
Abstract Alkane sulfonate carbamates are obtained as the result of reaction conducted between hydroxyalkane sulfonate and urea within the aromatic hydrocarbon solvent.
Inventors
- 👤 G Sendelweck
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 17:04
CPC Classifications
H; H04; H04N; H04N3/00; H04N3/10; H04N3/16; H04N3/20
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
127 words
A method for urethanation of hydroxyalkane sulfonates expressed by the following general formula, (I), comprising the steps of conducting reaction between said hydroxyalkane sulfonate and urea in an inert organic solvent in the molar ratio of 1 : 1.0 - 4.0 at a temperature within the range of 100* - 180* C; and recovering carbamic acid ester of hydroxy alkane sulfonate expressed by the following general formUla, (II) from reaction mixture resulted from said reaction. wherein R1 represents alkyl radical, R2 represents hydrogen or alkyl radical, (but the sum total of carbon atoms possessed by both R1 and R2 is 3 - 21), R3 represents absence or alkylene radical having one to three carbon atoms, and M represents alkali metal, alkali earth metal, ammonium, or substituted ammonium.
Claim 2
Independent Claim
127 words
A method for urethanation of hydroxyalkane sulfonates expressed by the following general formula, (I), comprising the steps of conducting reaction between said hydroxyalkane sulfonate and urea in an inert organic solvent in the molar ratio of 1 : 1.0 - 4.0 at a temperature within the range of 100* - 180* C; and recovering carbamic acid ester of hydroxy alkane sulfonate expressed by the following general formUla, (II) from reaction mixture resulted from said reaction. wherein R1 represents alkyl radical, R2 represents hydrogen or alkyl radical, (but the sum total of carbon atoms possessed by both R1 and R2 is 3 - 21), R3 represents absence or alkylene radical having one to three carbon atoms, and M represents alkali metal, alkali earth metal, ammonium, or substituted ammonium.
Claim 3
Independent Claim
127 words
A method for urethanation of hydroxyalkane sulfonates expressed by the following general formula, (I), comprising the steps of conducting reaction between said hydroxyalkane sulfonate and urea in an inert organic solvent in the molar ratio of 1 : 1.0 - 4.0 at a temperature within the range of 100* - 180* C; and recovering carbamic acid ester of hydroxy alkane sulfonate expressed by the following general formUla, (II) from reaction mixture resulted from said reaction. wherein R1 represents alkyl radical, R2 represents hydrogen or alkyl radical, (but the sum total of carbon atoms possessed by both R1 and R2 is 3 - 21), R3 represents absence or alkylene radical having one to three carbon atoms, and M represents alkali metal, alkali earth metal, ammonium, or substituted ammonium.
Claim 4
Independent Claim
127 words
A method for urethanation of hydroxyalkane sulfonates expressed by the following general formula, (I), comprising the steps of conducting reaction between said hydroxyalkane sulfonate and urea in an inert organic solvent in the molar ratio of 1 : 1.0 - 4.0 at a temperature within the range of 100* - 180* C; and recovering carbamic acid ester of hydroxy alkane sulfonate expressed by the following general formUla, (II) from reaction mixture resulted from said reaction. wherein R1 represents alkyl radical, R2 represents hydrogen or alkyl radical, (but the sum total of carbon atoms possessed by both R1 and R2 is 3 - 21), R3 represents absence or alkylene radical having one to three carbon atoms, and M represents alkali metal, alkali earth metal, ammonium, or substituted ammonium.
Claim 5
Dependent Claim
27 words
A method for urethanation of hydroxyalkane sulfonates according to claim 1, wherein urethanation is carried out at a temperature within the range of 120* - 140* C.
Claim 6
Dependent Claim
25 words
A method for urethanation of hydroxyalkane sulfonate according to claim 1, wherein the hydroxyalkane sulfonate to urea molar ratio is +1 : 1.2 - 3.0.
References Cited (Backward Citations)
US2806051A
Cited
US3068278A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-02-06 | 1976-08-07 | 1977-02-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-02-06 | 1980-08-07 | 1981-02-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-02-06 | 1984-08-07 | 1985-02-06 | $7700.00 | Window Closed / Lapsed |