Patent US3644498A successfully refreshed from Google Patents.
US3644498A
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US
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Yellow dye forming couplers for color photography
Assignee: Eastman Kodak Co
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Filing: 1967-06-26
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Granted: 1972-02-22
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Expires: 1987-06-26
Abstract
Abstract OPEN CHAIN REACTIVE METHYLENE TWO-EQUIVALENT YELLOWFORMING COUPLERS IN WHICH ONE OF LHE HYDROGEN ATOMS OF THE ACTICE METHYLENE GROUP IS REPLACED WITH A CYCLOOXY GROUP ARE USED TO ADVANTAGE IN COLOR DEVELOPER SOLUTIONS AND IN LIGHT-SENSITIVE PHOTOGRAPHIC EMULSION LAYERS OF FORMING YELLOW DYE IMAGES IN COLOR PHOTOGRAPHY
Inventors
- 👤 Anthony Loria
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 07:34
CPC Classifications
C; C07; C07C; C07C255/00; G; G03; G03C; G03C7/00; G03C7/30; G03C7/305; G03C7/30511; G03C7/30517; G03C7/30535; G03C7/32; G03C7/333; G03C7/3335; G03C8/00; G03C8/02; G03C8/08; G03C8/10
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) | 1975-02-21 | 1975-08-23 | 1976-02-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-02-21 | 1979-08-23 | 1980-02-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-02-21 | 1983-08-23 | 1984-02-22 | $7700.00 | Window Closed / Lapsed |