US3718614A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Polymeric viscosity control additives for silica thixotropic compositions
Assignee: Wyeth Holdings LLC
•
Filing: 1971-02-23
•
Granted: 1973-02-27
•
Expires: 1991-02-23
Abstract
Abstract Novel thixotropic compositions and processes for their formation employing as viscosity control additives therein members selected from the group consisting of: 1) homopolymers and copolymers of poly(alkylene oxides) having terminal alkyl groups; 2) homopolymers and copolymers of poly(vinyl alkyl esters) and poly(vinyl alkyl ethers) with the optional inclusion of minor amounts of alkylenes and styrenes in said copolymers; 3) 1:1 alternating copolymers of maleic anhydride with alkylenes and styrenes; 4) cellulose esters and mixed cellulose esters of 2-, 3- and 4-carbon acids and mixtures of said esters with the poly(alkylene oxides).
Inventors
- 👤 N Smyth
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 08:44
CPC Classifications
C; C09; C09D; C09D5/00; C09D5/04; C01; C01B; C01B33/00; C01B33/113
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
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) | 1976-02-27 | 1976-08-28 | 1977-02-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-02-27 | 1980-08-28 | 1981-02-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-02-27 | 1984-08-28 | 1985-02-27 | $7700.00 | Window Closed / Lapsed |