Patent DE692773C successfully refreshed from Google Patents.
US4259191A
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Process for the preparation of sulfobetaines
Assignee: Evonik Operations GmbH
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Filing: 1979-04-19
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Granted: 1981-03-31
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Expires: 1999-04-19
Abstract
Abstract A method for the preparation of sulfobetaines having the general formula ##STR1## The betaines possess excellent solubilizing and emulsification properties for use in oil recovery.
Inventors
- 👤 Helmut Wagner
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 22:12
CPC Classifications
C; C09; C09K; C09K8/00; C09K8/58; C09K8/584; Y; Y10; Y10S; Y10S507/00; Y10S507/935; Y10S507/936; Y10S516/00; Y10S516/01; Y10S516/03; Y10S516/05
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
105 words
In a method for recovering mineral oil from deposits thereof by flooding the deposit with an aqueous solution and recovering the oil from the flooding solution, the improvement which comprises flooding the deposit with an aqueous solution containing from about 0.0005 to 5 weight percent of a sulfobetaine having the formula ##STR11## wherein R 1 is a naphthenoyl residue, R 2 is an alkyl residue with 2 to 6 carbon atoms, R 3 and R 4 may be the same or different and represent linear alkyl residues with 1 to 4 carbon atoms, R 5 is an alkylene residue with 1 to 4 carbon atoms.
Claim 2
Dependent Claim
105 words
In a method for recovering mineral oil from deposits thereof by flooding the deposit with an aqueous solution and recovering the oil from the flooding solution, the improvement which comprises flooding the deposit with an aqueous solution containing from about 0.0005 to 5 weight percent of a sulfobetaine having the formula ##STR11## wherein R 1 is a naphthenoyl residue, R 2 is an alkyl residue with 2 to 6 carbon atoms, R 3 and R 4 may be the same or different and represent linear alkyl residues with 1 to 4 carbon atoms, R 5 is an alkylene residue with 1 to 4 carbon atoms.
Claim 3
Dependent Claim
14 words
The method of claim 1 wherein R 2 contains 2 or 3 carbon atoms.
Claim 4
Dependent Claim
19 words
The method of claim 1 or 2 wherein R 3 and R 4 contain 1 or 2 carbon atoms.
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) | 1984-03-30 | 1984-09-29 | 1985-03-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-03-30 | 1988-09-29 | 1989-03-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-03-30 | 1992-09-29 | 1993-03-31 | $7700.00 | Window Closed / Lapsed |