US3157599A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Drilling fluid
Assignee: Hercules Powder Co
•
Filing: 1961-07-07
•
Granted: 1964-11-17
•
Expires: 1981-07-07
Abstract
No abstract record available.
Inventors
- 👤 Walter E Gloor
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 22:59
CPC Classifications
C; C09; C09K; C09K8/00; C09K8/02; C09K8/04; C09K8/14; C09K8/18; C09K8/22; C09K8/24
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
85 words
A DRILLING FLUID COMPRISING AN AQUEOUS SUSPENSION OF FINELY DIVIDED, SOLID, INORGANIC MATERIAL AND AS A WATERLOSS PREVENTIVE AN AGENT PREPARED FROM DIVINYL ETHER AND MALEIC ANHYDRIDE IN THE MOLAR RATIO OF ABOUT 1:2 AND SELECTED FROM THE GROUP CONSISTING OF DIVINYL ETHER-MALEIC ANHYDRIDE COPOLYMERS, ALKALI METAL, AMMONIUM, HALF ANIDE-HALF AMMONIUM, AND ALKYL AMINE SALTS OF DIVINYL ETHER-MALEIC ANHYDRIDE COPOLYMERS, WATER-SOLUBLE PARTIAL ESTERS OF LOWER MONOHYDROXY ALIPHATIC ALCOHOLS WITH DIVINYL ETHER-MALEIC ANHYDRIDE COPOLYMERS AND WATER-SOLUBLE PARTIAL ESTERS OF ALKANOL AMINES WITH DIVINYL ETHERMALEIC ANHYDRIDE COPOLYMERS.
Claim 2
Dependent Claim
85 words
A DRILLING FLUID COMPRISING AN AQUEOUS SUSPENSION OF FINELY DIVIDED, SOLID, INORGANIC MATERIAL AND AS A WATERLOSS PREVENTIVE AN AGENT PREPARED FROM DIVINYL ETHER AND MALEIC ANHYDRIDE IN THE MOLAR RATIO OF ABOUT 1:2 AND SELECTED FROM THE GROUP CONSISTING OF DIVINYL ETHER-MALEIC ANHYDRIDE COPOLYMERS, ALKALI METAL, AMMONIUM, HALF ANIDE-HALF AMMONIUM, AND ALKYL AMINE SALTS OF DIVINYL ETHER-MALEIC ANHYDRIDE COPOLYMERS, WATER-SOLUBLE PARTIAL ESTERS OF LOWER MONOHYDROXY ALIPHATIC ALCOHOLS WITH DIVINYL ETHER-MALEIC ANHYDRIDE COPOLYMERS AND WATER-SOLUBLE PARTIAL ESTERS OF ALKANOL AMINES WITH DIVINYL ETHERMALEIC ANHYDRIDE COPOLYMERS.
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) | 1967-11-17 | 1968-05-18 | 1968-11-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1971-11-17 | 1972-05-18 | 1972-11-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1975-11-17 | 1976-05-18 | 1976-11-17 | $7700.00 | Window Closed / Lapsed |