US2900335A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Oil well drilling mud
Assignee: Cerestar USA Inc
•
Filing: 1956-06-13
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Granted: 1959-08-18
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Expires: 1976-06-13
Abstract
No abstract record available.
Inventors
- 👤 George T Bravos
- 👤 James W Evans
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 21:11
CPC Classifications
C; C09; C09K; C09K8/00; C09K8/02; C09K8/04; C09K8/14; C09K8/18; C09K8/20; C09K8/206
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
100 words
AN OIL WELL DRILLING FLUID COMPRISING AN AQUEOUS SUSPENSION OF COLLOIDAL CLAY AND PREGELATINIZED CEREAL STARCH WHICH STARCH IS THE DRIED PRODUCT OF PASTING CEREAL STARCH GRANULES IN AQUEOUS SLURRY CONTAINING ABOUT 10% TO 45% BY WEIGHT OF STARCH SOLIDS AND ABOUT 0.1% TO 3.0% OF A WATER SOLUBLE ALKALINE EARTH METAL SLAT BY WEIGHT OF THE STARCH GRANULES, SAID DRIED STARCH PRODUCT HAVING A WATER HOLDING CAPACITY EQUIVALENT TO A "WALL TEST" OF LESS THAN 12.5 ML WATER LOSS AND BEING PRESENT IN THE DRILLING FLUID IN AN AMOUNT SUFFICIENT OT INCREASE THE WATER HOLDING CAPACITY OF THE FLUID.
Claim 2
Dependent Claim
100 words
AN OIL WELL DRILLING FLUID COMPRISING AN AQUEOUS SUSPENSION OF COLLOIDAL CLAY AND PREGELATINIZED CEREAL STARCH WHICH STARCH IS THE DRIED PRODUCT OF PASTING CEREAL STARCH GRANULES IN AQUEOUS SLURRY CONTAINING ABOUT 10% TO 45% BY WEIGHT OF STARCH SOLIDS AND ABOUT 0.1% TO 3.0% OF A WATER SOLUBLE ALKALINE EARTH METAL SLAT BY WEIGHT OF THE STARCH GRANULES, SAID DRIED STARCH PRODUCT HAVING A WATER HOLDING CAPACITY EQUIVALENT TO A "WALL TEST" OF LESS THAN 12.5 ML WATER LOSS AND BEING PRESENT IN THE DRILLING FLUID IN AN AMOUNT SUFFICIENT OT INCREASE THE WATER HOLDING CAPACITY OF THE FLUID.
References Cited (Backward Citations)
US1939236A
Cited
US2417307A
Cited
US2508533A
Cited
US2514055A
Cited
US2600404A
Cited
US2658035A
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1962-08-17 | 1963-02-16 | 1963-08-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1966-08-17 | 1967-02-16 | 1967-08-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1970-08-17 | 1971-02-16 | 1971-08-18 | $7700.00 | Window Closed / Lapsed |