US2640810A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Treatment of wells
Assignee: Dow Chemical Co
•
Filing: 1950-09-14
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Granted: 1953-06-02
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Expires: 1970-09-14
Abstract
No abstract record available.
Inventors
- 👤 Paul H Cardwell
- 👤 Charles L Lunsford
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 14:18
CPC Classifications
C; C09; C09K; C09K8/00; C09K8/60; C09K8/62; C09K8/72; Y; Y10; Y10S; Y10S507/00; Y10S507/933; Y10S507/934
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
51 words
IN ACIDIZING WITH AQUEOUS HYDROCHLORIC ACID A CALCAREOUS FORMATION CONTAINING A SILICATE CAPABLE OF SWELLING AS THE ACID BECOMES SPENT ON ATTACKING THE CALCAREOUS MATTER, THE IMPROVED ACIDIZING METHOD WHICH CONSISTS IN INCLUDING IN THE ACID SOLUTION A BUFFERING AGENT SELECTED FROM THE GROUP CONSISTING OF FORMIC ACID AND ITS SALT.
Claim 2
Dependent Claim
51 words
IN ACIDIZING WITH AQUEOUS HYDROCHLORIC ACID A CALCAREOUS FORMATION CONTAINING A SILICATE CAPABLE OF SWELLING AS THE ACID BECOMES SPENT ON ATTACKING THE CALCAREOUS MATTER, THE IMPROVED ACIDIZING METHOD WHICH CONSISTS IN INCLUDING IN THE ACID SOLUTION A BUFFERING AGENT SELECTED FROM THE GROUP CONSISTING OF FORMIC ACID AND ITS SALT.
References Cited (Backward Citations)
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Cited
US2024718A
Cited
US2045899A
Cited
US2234790A
Cited
US2301875A
Cited
US2238671A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1956-06-01 | 1956-12-01 | 1957-06-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1960-06-01 | 1960-12-01 | 1961-06-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1964-06-01 | 1964-12-01 | 1965-06-02 | $7700.00 | Window Closed / Lapsed |