US2552775A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Drilling fluid
Assignee: Union Oil Company of California
•
Filing: 1948-03-20
•
Granted: 1951-05-15
•
Expires: 1968-03-20
Abstract
No abstract record available.
Inventors
- 👤 Paul W Fischer
- 👤 James F Cook
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 08:08
CPC Classifications
C; C09; C09K; C09K8/00; C09K8/02; C09K8/04; C09K8/14; C09K8/18; C09K8/22; C09K8/24; Y; Y10; Y10S; Y10S260/00; Y10S260/14; Y10S71/00; Y10S71/903
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
55 words
A DRILLING FLUID WHICH COMPRISES AN AQUEOUS SUSPENSION OF CLAY 0.5 TO 5.0% BY WEIGHT OF AN ALKALI METAL SALT OF POLYMER OF ACRYLIC ACID HAVING AN AVERAGE MOLECULAR WEIGHT OF BETWEEN 5,000 AND 50,000 AND 3 TO 7% BY WEIGHT OF A CHLORIDE SELECTED FROM THE CLASS CONSISTING OF AMMONIUM AND ALKALI METAL CHLORIDES.
Claim 2
Dependent Claim
55 words
A DRILLING FLUID WHICH COMPRISES AN AQUEOUS SUSPENSION OF CLAY 0.5 TO 5.0% BY WEIGHT OF AN ALKALI METAL SALT OF POLYMER OF ACRYLIC ACID HAVING AN AVERAGE MOLECULAR WEIGHT OF BETWEEN 5,000 AND 50,000 AND 3 TO 7% BY WEIGHT OF A CHLORIDE SELECTED FROM THE CLASS CONSISTING OF AMMONIUM AND ALKALI METAL CHLORIDES.
References Cited (Backward Citations)
US1976679A
Cited
US2209591A
Cited
US2204520A
Cited
US2244703A
Cited
US2318429A
Cited
US2317328A
Cited
US2425768A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1954-05-14 | 1954-11-13 | 1955-05-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1958-05-14 | 1958-11-13 | 1959-05-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1962-05-14 | 1962-11-13 | 1963-05-15 | $7700.00 | Window Closed / Lapsed |