US3639128A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Ferrous complex of n-containing heterocyclic compound as silver latent image stabilizer
Assignee: Bayer AG
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Filing: 1969-07-09
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Granted: 1972-02-01
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Expires: 1989-07-09
Abstract
Abstract Photographic material comprising at least one silver halide emulsion layer, which is improved with respect to the stability of the latent image and the final silver image by addition of a complex compound of iron with a nitrogen-containing heterocyclic compound having a five- or six-membered heterocyclic ring as ligand.
Inventors
- 👤 Reinhard Matejec
- 👤 Rudolf Meyer
- 👤 Wolfgang Himmelmann
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 15:25
CPC Classifications
G; G03; G03C; G03C1/00; G03C1/005; G03C1/06; G03C1/34
Claims Analysis
Total Claims: 1
Claim 1
Independent Claim
52 words
The photographic material of claim 1, wherein the binding agent of the emulsion layer comprises a material selected from the group consisting of casein, albumine, starch or a starch derivative, cellulose or a cellulose derivative, alginic acid or an alginic acid derivative, polyvinyl pyrrolidine, polyvinyl-alcohol, partly hydrolyzed polyvinyl acetate or colloidal silica.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-01-31 | 1975-08-02 | 1976-02-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-01-31 | 1979-08-02 | 1980-02-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-01-31 | 1983-08-02 | 1984-02-01 | $7700.00 | Window Closed / Lapsed |