Patent US4845021A successfully refreshed from Google Patents.
US3178294A
Expired / Lapsed
US
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Process for production of photographic silver halide emulsions
Assignee: Agfa Gevaert NV
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Filing: 1961-02-08
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Granted: 1965-04-13
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Expires: 1981-02-08
Abstract
No abstract record available.
Inventors
- 👤 Kinkel Ernst
- 👤 Jerenz Hans
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 16:21
CPC Classifications
G; G03; G03C; G03C1/00; G03C1/005; G03C1/015; C; C08; C08F; C08F8/00; C08F8/34; C08F2800/00; C08F2800/20
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
83 words
PROCESS FOR THE PRODUCTION OF PHOTOGRAPHIC SILVER HALIDE EMULSIONS WHICH COMPRISES PROVIDING A GELATINE EMULSION OF SILVER HALIDE, IN WATER, MIXING SAID EMULSION WITH THE SULFONATED COPOLYMER OF VINYL PYRIDINE AND A POLYMERIZABLE MONOMER SELECTED FROMTHE CLASS CONSISTING OF ACRYLIC ACID, METHACRYLIC ACID, ACRYLONITRILE, METHACRYLONITRILE, STYRENE SULFONIC ACID, DIVINYL BENZENE SULFONIC ACID, AND ACRYLAMIDE, AND FLOCCULATILNG SAID EMULSION IN ALKALINE MEDIUM TO FORM A SILVER HALIDE FLOCCULATE, SEPARATING SAID FLOCCULATE FROM THE REACTION MIXTURE, AND THEN DISPERSING SAID FLOCCULATE ILN A GELATINE SOLUTION.
Claim 2
Dependent Claim
83 words
PROCESS FOR THE PRODUCTION OF PHOTOGRAPHIC SILVER HALIDE EMULSIONS WHICH COMPRISES PROVIDING A GELATINE EMULSION OF SILVER HALIDE, IN WATER, MIXING SAID EMULSION WITH THE SULFONATED COPOLYMER OF VINYL PYRIDINE AND A POLYMERIZABLE MONOMER SELECTED FROMTHE CLASS CONSISTING OF ACRYLIC ACID, METHACRYLIC ACID, ACRYLONITRILE, METHACRYLONITRILE, STYRENE SULFONIC ACID, DIVINYL BENZENE SULFONIC ACID, AND ACRYLAMIDE, AND FLOCCULATILNG SAID EMULSION IN ALKALINE MEDIUM TO FORM A SILVER HALIDE FLOCCULATE, SEPARATING SAID FLOCCULATE FROM THE REACTION MIXTURE, AND THEN DISPERSING SAID FLOCCULATE ILN A GELATINE SOLUTION.
References Cited (Backward Citations)
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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) | 1968-04-12 | 1968-10-12 | 1969-04-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1972-04-12 | 1972-10-12 | 1973-04-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1976-04-12 | 1976-10-12 | 1977-04-13 | $7700.00 | Window Closed / Lapsed |