US2828258A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Aqueous drilling fluid
Assignee: Sunoco Inc
•
Filing: 1955-11-28
•
Granted: 1958-03-25
•
Expires: 1975-11-28
Abstract
No abstract record available.
Inventors
- 👤 William E Thompson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 18:03
CPC Classifications
C; C09; C09K; C09K8/00; C09K8/02; C09K8/04; C09K8/14; C09K8/16
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
88 words
AN AQUEOUS DRILLING FLUID HAVING IMPROVED RESISTANCE TO THICKENING UNDER HIGH TEMPERATURE WELL CONDITIONS WHICH COMPRISES A HYDRATABLE CLAY, AN ALKALI METAL HYDROXIDE AND A CLAY DISPERENT SELECTED FROM THE GROUP CONSISTING OF TANNIN EXTRACTS AND LIGNOSULFONATES, SAID DRILLING FLUID HAVING INCORPORATED THEREIN MANGESIUM HYDROXIDE AND ANOTHER ALKALINE EARTH METAL HYDROXIDE SELECTED FROM THE GROUP CONSISTING OF CALCIUM HYDROXIDE AND BARIUM HYDROXIDE, SAID HYDROXIDES, EACH BEING INCORPORATED IN THE MISTURE IN AMOUNT OF AT LEAST 1 LB./BBL. AND IN THE DROXIDE WITHIN THE RANGE OF 3:1 TO 2:3.
Claim 2
Dependent Claim
88 words
AN AQUEOUS DRILLING FLUID HAVING IMPROVED RESISTANCE TO THICKENING UNDER HIGH TEMPERATURE WELL CONDITIONS WHICH COMPRISES A HYDRATABLE CLAY, AN ALKALI METAL HYDROXIDE AND A CLAY DISPERENT SELECTED FROM THE GROUP CONSISTING OF TANNIN EXTRACTS AND LIGNOSULFONATES, SAID DRILLING FLUID HAVING INCORPORATED THEREIN MANGESIUM HYDROXIDE AND ANOTHER ALKALINE EARTH METAL HYDROXIDE SELECTED FROM THE GROUP CONSISTING OF CALCIUM HYDROXIDE AND BARIUM HYDROXIDE, SAID HYDROXIDES, EACH BEING INCORPORATED IN THE MISTURE IN AMOUNT OF AT LEAST 1 LB./BBL. AND IN THE DROXIDE WITHIN THE RANGE OF 3:1 TO 2:3.
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) | 1961-03-24 | 1961-09-23 | 1962-03-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1965-03-24 | 1965-09-23 | 1966-03-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1969-03-24 | 1969-09-23 | 1970-03-25 | $7700.00 | Window Closed / Lapsed |