Patent US3733335A successfully refreshed from Google Patents.
US3733335A
Expired / Lapsed
US
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Indazolone magenta couplers
Assignee: Ilford Imaging UK Ltd
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Filing: 1971-01-06
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Granted: 1973-05-15
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Expires: 1991-01-06
Abstract
Abstract THIS APPLICATION DESCRIBES AN INDAZOLONE MAGNETA COUPLER OF THE FORMULA: 3-(O=),Q-2,3-DIHYDRO-1H-INDAZOLE WHERE Q IS EITHER A GROUP -NH-R WHEREIN R IS AN ACYL GROUP CONTAINING A NITROGEN ATOM TO WHICH THERE IS ATTACHED EITHER DIRECTLY OR VIA A PHENYL GROUP AN ALKYL RESIDUE OF AT LEAST 10 CARBON ATOMS, TOGETHER WITH A FREE CARBOXYLIC ACID GROUP OR A GROUP WHICH CAN LIBERATE A FREE CARBOXYLIC ACID GROUP OR Q IS A GROUP -N<(T) WHEREIN T IS AN ACYL GROUP WHICH IS ATTACHED TO THE NITROGEN ATOM BY A CYCLIC IMIDE LINKAGE, THE GROUP T CONTAINING AN ALKYL RESIDUE OF AT LEAST 10 CARBON ATOMS, THE RING TO WHICH Q IS ATTACHED OPTIONALLY CONTAINING OTHER SUBSTITUENTS.
Inventors
- 👤 B Anderson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 22:40
CPC Classifications
G; G03; G03C; G03C7/00; G03C7/30; G03C7/32; G03C7/3231
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) | 1976-05-14 | 1976-11-13 | 1977-05-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-05-14 | 1980-11-13 | 1981-05-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-05-14 | 1984-11-13 | 1985-05-15 | $7700.00 | Window Closed / Lapsed |