US4288535A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for preparing silver halide photographic emulsions
Assignee: Konica Minolta Inc
•
Filing: 1980-05-19
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Granted: 1981-09-08
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Expires: 2000-05-19
Abstract
Abstract A process for preparing silver halide emulsions having high sensitivity and contrast by adding water-soluble iridium compounds during precipitation or physical ripening and adding water-soluble iodide compounds and sulfer sensitizers during chemical ripening.
Inventors
- 👤 Hideo Kanisawa
- 👤 Tamio Kitahata
- 👤 Hideo Horie
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 03:20
CPC Classifications
G; G03; G03C; G03C1/00; G03C1/005; G03C1/06; G03C1/08; G03C1/09; G03C1/07; G03C1/10; G03C1/12; G03C1/22; G03C1/035; G03C2001/03517; G03C2001/093; G03C2001/094; G03C2001/095; Y; Y10; Y10S; Y10S430/00; Y10S430/15; Y10S430/164
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
78 words
A process for preparing a silver halide photographic emulsion which process comprises adding a water-soluble iridium compound in an amount of 10 -7 to 10 -4 mole per mole of the silver halide at the stage of precipitation of silver halide grains or physical ripening thereof, and adding a water-soluble iodide in an amount of 10 -4 to 10 -2 mole per mole of the silver halide and a sulfur sensitizer at the stage of chemical ripening thereof.
Claim 2
Dependent Claim
78 words
A process for preparing a silver halide photographic emulsion which process comprises adding a water-soluble iridium compound in an amount of 10 -7 to 10 -4 mole per mole of the silver halide at the stage of precipitation of silver halide grains or physical ripening thereof, and adding a water-soluble iodide in an amount of 10 -4 to 10 -2 mole per mole of the silver halide and a sulfur sensitizer at the stage of chemical ripening thereof.
Claim 3
Dependent Claim
27 words
A process according to claim 1, wherein the amount of the sulfur sensitizer is 5×10 -6 mole to 5×10 -4 mole per mole of the silver halide.
Claim 4
Dependent Claim
14 words
A process according to claim 1, wherein the sulfur sensitizer is a water-soluble thiosulfate.
Claim 5
Dependent Claim
30 words
A process according to claim 1, wherein a water-soluble rhodate in an amount equal to or less than that of the iridium compound is added at the stage of precipitation.
Claim 6
Dependent Claim
20 words
A process according to claim 1, wherein the water-soluble iridium compound is iridium chloride, potassium iridium chloride or ammonium hexachloroiridate.
Claim 7
Dependent Claim
22 words
A process according to claim 1, wherein the water-soluble iodide is sodium iodide, potassium iodide, magnesium iodide, calcium iodide or ammonium iodide.
Claim 8
Dependent Claim
14 words
A process according to claim 4, wherein the water-soluble rhodium compound is rhodium chloride.
Claim 9
Dependent Claim
18 words
A process according to claim 1, wherein the silver halide contains at least 50 mol% of silver chloride.
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) | 1984-09-07 | 1985-03-09 | 1985-09-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-09-07 | 1989-03-09 | 1989-09-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-09-07 | 1993-03-09 | 1993-09-08 | $7700.00 | Window Closed / Lapsed |