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US3652279A Expired / Lapsed US ⏱️ 0.0 years remaining

Nitrogen-containing dmax maintainers for use in photosoluble emulsions

Assignee: EIDP Inc
•
Filing: 1969-07-18
•
Granted: 1972-03-28
•
Expires: 1989-07-18
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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 07:24
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)

US2497917A Cited
US3155507A Cited
US3493373A Cited
US3495982A Cited

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

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