Patent US3765893A successfully refreshed from Google Patents.
US3765893A
Expired / Lapsed
US
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Polymeric acid containing gelatin interlayer for color photographic film
Assignee: Agfa Gevaert AG
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Filing: 1972-05-10
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Granted: 1973-10-16
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Expires: 1992-05-10
Abstract
Abstract Color-photographic multi-layer materials having red-sensitized, green-sensitized, and blue-sensitized silver halide emulsion layers, each emulsion layer containing a color coupler, and gelatin interlayers for preventing undesirable coupling of developer oxidation products diffused in adjacent silver halide emulsion layers, contain in the gelatin interlayers 5 to 30 percent by weight of polyerms which contain acid groups. These interlayers are more effective in preventing the diffusion of developer oxidation products, as compared with pure gelatin interlayers. Thus it is possible to have interlayers of half the thickness of conventional interlayers. The materials have improved non-curling properties.
Inventors
- 👤 K Lohmer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 23:03
CPC Classifications
G; G03; G03C; G03C1/00; G03C1/76; G03C1/81; G03C7/00; G03C7/30; G03C7/3029; G03C7/388; G03C7/3882; G03C7/392; G03C7/396
Claims Analysis
Total Claims: 1
Claim 1
Independent Claim
79 words
The combination of claim 1, wherein the polymer containing acid groups is selected from the group consisting of polymers and copolymers of acrylic acid and copolymers of maleic acid containing 0.2 to 1 carboxylic acid groups per monomeric unit, poly styrene sulfonic acid containing 0.5 to 1 sulfonic acid groups per styrene unit, carboxy methyl cellulose containing 0.5 to 1 carboxylic acid groups per glucose unit, and cellulose sulfate containing 1 to 2 sulfuric acid groups per glucose unit.
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) | 1976-10-15 | 1977-04-16 | 1977-10-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-10-15 | 1981-04-16 | 1981-10-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-10-15 | 1985-04-16 | 1985-10-16 | $7700.00 | Window Closed / Lapsed |