US3186840A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Direct positive colored photographic elements containing dihydrazones and process for forming colored masks therefrom
Assignee: Agfa Gevaert NV
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Filing: 1959-12-08
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Granted: 1965-06-01
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Expires: 1979-12-08
Abstract
No abstract record available.
Inventors
- 👤 Puschel Walter
- 👤 Wahl Ottmar
- 👤 Pelz Willibald
- 👤 Schellenberger Hans
- 👤 Loffler Karl
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 07:44
CPC Classifications
C; C07; C07D; C07D213/00; C07D213/02; C07D213/04; C07D213/24; C07D213/44; C07D213/53; C07D277/00; C07D277/60; C07D277/62; C07D277/68; C07D277/82; C07D307/00; C07D307/77; C07D307/78; C07D307/79; C07D307/81; C07D307/82; G; G03; G03C; G03C7/00; G03C7/18; G03C7/30; G03C7/392; G03C7/39208; G03C7/39224
Claims Analysis
Total Claims: 1
Claim 1
Independent Claim
70 words
A PROCESS OF PRODUCING A MASKING IMAGE IN A MULTILAYER PHOTOGRAPHIC MATERIAL COMPRISING SEVERAL SIL-VER HALIDE EMULSION LAYERS, WHEREIN AT LEAST ONE OF THE SAID LAYERS CONTAINS AN UNCOLORED COLOR-FORMING COUPLER WHICH IS REACTIVE WITH THE OXIDATION PRODUCT OF A PRIMARY AROMATIC AMINE DEVELOPING AGENT TO FORM A DYESTUFF IN THE SAID LAYER, AND WHEREIN AT LEAST ONE OF THE SAID LAYERS CONTAINS A DIHYDRAZONE OF THE FOLLOWING GENERAL FORMULA
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1968-05-31 | 1968-11-30 | 1969-06-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1972-05-31 | 1972-11-30 | 1973-06-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1976-05-31 | 1976-11-30 | 1977-06-01 | $7700.00 | Window Closed / Lapsed |