US3689274A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process of hardening photographic gelatin layers with a sulfonyl ester or a sulfonamide
Assignee: Agfa Gevaert AG
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Filing: 1971-08-06
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Granted: 1972-09-05
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Expires: 1991-08-06
Abstract
Abstract A PROCESS OF HARDENING THE GELATIN OF A PHOTOGRAPHIC LAYER BY THE ADDITION OF A SULFONYL ESTER OR A SULFONAMIDE TO THE CASEIN SOLUTION.
Inventors
- 👤 Johannes Sobel
- 👤 Wolfgang Himmelmann
- 👤 Heinz Meckl
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 08:21
CPC Classifications
G; G03; G03C; G03C1/00; G03C1/005; G03C1/06; G03C1/30
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) | 1975-09-05 | 1976-03-06 | 1976-09-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-09-05 | 1980-03-06 | 1980-09-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-09-05 | 1984-03-06 | 1984-09-05 | $7700.00 | Window Closed / Lapsed |