US2837521A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for making polyazaindenes
Assignee: Eastman Kodak Co
•
Filing: 1956-04-11
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Granted: 1958-06-03
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Expires: 1976-04-11
Abstract
No abstract record available.
Inventors
- 👤 Donald M Burness
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 23:27
CPC Classifications
C; C07; C07D; C07D471/00; C07D471/02; C07D471/04; C07D487/00; C07D487/02; C07D487/04; G; G03; G03C; G03C1/00; G03C1/005; G03C1/06; G03C1/34
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
21 words
A PROCESS FOR PREPARING POLYAZAINDENE COMPOUNDS COMPRISING CONDENSING TOGETHER A B-KETOACETAL SELECTED FROM THOSE REPRESENTED BY THE FOLLOWING TWO GENERAL FORMULAS:
Claim 2
Dependent Claim
21 words
A PROCESS FOR PREPARING POLYAZAINDENE COMPOUNDS COMPRISING CONDENSING TOGETHER A B-KETOACETAL SELECTED FROM THOSE REPRESENTED BY THE FOLLOWING TWO GENERAL FORMULAS:
References Cited (Backward Citations)
US2553500A
Cited
US2566658A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1961-06-02 | 1961-12-02 | 1962-06-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1965-06-02 | 1965-12-02 | 1966-06-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1969-06-02 | 1969-12-02 | 1970-06-03 | $7700.00 | Window Closed / Lapsed |