US3200097A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Polyanhydrides
Assignee: Celanese Corp
•
Filing: 1959-05-25
•
Granted: 1965-08-10
•
Expires: 1979-05-25
Abstract
No abstract record available.
Inventors
- 👤 Thomas B Windholz
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 04:32
CPC Classifications
C; C08; C08G; C08G67/00; C08G67/04
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
32 words
A METHOD OF PREPARING OF POLYMERIC MIXED ANHYDRIDE OF A DICARBOXYLIC ACID AND A BIS-CARBONIC ESTER, SAID POLYMERIC MIXED ANHYDRIDE CONSISTING ESSENTIALLY OF A LEAST SIX SUCCESSIVELY RECURRING UNITS OF THE FORMULA
Claim 2
Independent Claim
32 words
A METHOD OF PREPARING OF POLYMERIC MIXED ANHYDRIDE OF A DICARBOXYLIC ACID AND A BIS-CARBONIC ESTER, SAID POLYMERIC MIXED ANHYDRIDE CONSISTING ESSENTIALLY OF A LEAST SIX SUCCESSIVELY RECURRING UNITS OF THE FORMULA
References Cited (Backward Citations)
US2799667A
Cited
US2870124A
Cited
US2808390A
Cited
US2787630A
Cited
GB801412A
Cited
US3030331A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1968-08-09 | 1969-02-08 | 1969-08-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1972-08-09 | 1973-02-08 | 1973-08-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1976-08-09 | 1977-02-08 | 1977-08-10 | $7700.00 | Window Closed / Lapsed |