Patent US3878639A successfully refreshed from Google Patents.
Patent US3652279A successfully refreshed from Google Patents.
US3652279A
Expired / Lapsed
US
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Nitrogen-containing dmax maintainers for use in photosoluble emulsions
Assignee: EIDP Inc
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Filing: 1969-07-18
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Granted: 1972-03-28
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Expires: 1989-07-18
Abstract
Abstract An improved process for forming a silver halide image by selective exposure of a photosoluble silver halide layer and dissolution of the exposed photosoluble silver halide in a silver halide solvent characterized by the presence in either the layer, solvent, or both, of a heterocyclic nitrogen-containing compound which loses a proton to form anions at an elevated pH, e.g., benzotriazoles, naphthotriazoles, 5-nitroimidazoles, and 6nitroindazole, which compounds enhance the action of mercaptan insolubilizers in photosoluble emulsions. New photosoluble elements for making direct positive images are provided by the invention.
Inventors
- 👤 Ralph Kingsley Blake
- 👤 Joseph De Witt Overman
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 17:37
CPC Classifications
G; G03; G03C; G03C1/00; G03C1/005; G03C1/492
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
22 words
A process according to claim 1, wherein the amount is in the range 0.2 to 1.33 grams per mole of silver halide.
Claim 2
Dependent Claim
16 words
A process according to claim 1, wherein the organic compound containing sulfur and oxygen is 2-mercapto-4-phenylthiazole.
Claim 3
Dependent Claim
28 words
A process according to claim 1, wherein the heterocyclic nitrogen-containing compound is present in the aqueous silver halide solvent solution having a pH of at least about 8.
Claim 4
Dependent Claim
19 words
A process according to claim 1, wherein the heterocyclic nitrogen-containing compound is present initially in the silver halide emulsion.
Claim 5
Dependent Claim
57 words
In a photographic element comprising a support bearing a photosoluble silver halide layer containing an organic compound containing sulfur and nitrogen as the insolubilizing compound the improvement comprising the presence in said layer of a heterocyclic nitrogen-containing compound containing at least 2 intracyclic nitrogen atoms being taken from the group consisting of benzotriazoles, 1,2-naphthotriazoles, nitrobenzimidazoles, and nitroindazoles.
Claim 6
Dependent Claim
23 words
An element according to claim 6, wherein said heterocyclic nitrogen-containing compound is taken from the group consisting of benzotriazole, 1,2-naphthotriazole, 5-nitrobenzimidazole, and 6-nitroindazole.
Claim 7
Dependent Claim
23 words
A process according to claim 1, wherein said heterocyclic nitrogen-containing compound is selected from the group consisting of benzotriazole, 1,2-naphtho-triazole, 5-nitrobenzimidazole, and 6-nitroindazole.
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) | 1975-03-28 | 1975-09-27 | 1976-03-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-03-28 | 1979-09-27 | 1980-03-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-03-28 | 1983-09-27 | 1984-03-28 | $7700.00 | Window Closed / Lapsed |