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Patent US3796727A successfully refreshed from Google Patents.
US3796727A
Expired / Lapsed
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Synthesis of novel benzopyran compounds
Assignee: Eastman Kodak Co
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Filing: 1972-01-31
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Granted: 1974-03-12
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Expires: 1992-01-31
Abstract
Abstract NOVEL 2H-3-SUBSTITUTED 5,6-BENZOPYRANS AND PROCESSES FOR THIER PREPARATION ARE DISCLOSED. VINYL KETONE COMPOUNDS ARE RELATED UNDER BASIC CONDITIONS WITH O-HYDROXYBENZALDEHYDES TO FORM THE NOVEL BENZOPYRAN COMPOUNDS. THE COMPOUNDS CAN BE USED TO PREPARE LIGHTSENSITIVE POLYMERS USEFUL IN PHOTOSENSITIVE ELEMENTS AND PROCESSES.
Inventors
- 👤 C Deboer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 13:15
CPC Classifications
C; C07; C07D; C07D311/00; C07D311/02; C07D311/04; C07D311/58
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-03-11 | 1977-09-10 | 1978-03-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-03-11 | 1981-09-10 | 1982-03-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-03-11 | 1985-09-10 | 1986-03-12 | $7700.00 | Window Closed / Lapsed |