Patent US2843545A successfully refreshed from Google Patents.
US2843545A
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Secondary oil recovery by water flooding operations
Assignee: Dow Chemical Co
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Filing: 1956-01-12
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Granted: 1958-07-15
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Expires: 1976-01-12
Abstract
No abstract record available.
Inventors
- 👤 Paul A Wolf
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 13:34
CPC Classifications
C; C09; C09K; C09K8/00; C09K8/60; C09K8/605; Y; Y10; Y10S; Y10S507/00; Y10S507/935; Y10S507/936
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
54 words
A FLOODING PROCESS FOR RECOVERING OIL FROM AN OIL BEARING STRATUM IN AN EARTH FORMATION WHICH COMPRISES INJECTING INTO THE STRATUM A FLOODING WATER CONTAINING A WATER-SOLUBLE CONDENSATION PRODUCT OBTAINED BY THE REACTION OF FROM 2.0 TO 3.5 MOLECULAR PROPORTIONS OF FORMALDEHYDE WITH 1.0 MOLECULAR PROPORTION OF AN ALIPHATIC POLYMAMINE HAVING THE GENERAL FORMULA:
Claim 2
Dependent Claim
54 words
A FLOODING PROCESS FOR RECOVERING OIL FROM AN OIL BEARING STRATUM IN AN EARTH FORMATION WHICH COMPRISES INJECTING INTO THE STRATUM A FLOODING WATER CONTAINING A WATER-SOLUBLE CONDENSATION PRODUCT OBTAINED BY THE REACTION OF FROM 2.0 TO 3.5 MOLECULAR PROPORTIONS OF FORMALDEHYDE WITH 1.0 MOLECULAR PROPORTION OF AN ALIPHATIC POLYMAMINE HAVING THE GENERAL FORMULA:
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) | 1961-07-14 | 1962-01-13 | 1962-07-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1965-07-14 | 1966-01-13 | 1966-07-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1969-07-14 | 1970-01-13 | 1970-07-15 | $7700.00 | Window Closed / Lapsed |