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US4049458A Expired / Lapsed US ⏱️ 0.0 years remaining

Photographic silver halide material containing 2-equivalent yellow couplers

Assignee: Agfa Gevaert AG
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Filing: 1975-08-13
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Granted: 1977-09-20
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Expires: 1995-08-13
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Abstract

Abstract Desirable 2-equivalent yellow couplers carry at the coupling position a monocyclic pyrrole, diazole or triazole ring attached to the coupling position of the yellow coupler by a nitrogen atom, which ring can be split off in the coupling reaction. Photographic 2-equivalent yellow couplers with nitrogen-containing heterocyclic splittable groups having such nitrogen bonded to the coupling position of the couplers, are prepared by reacting a corresponding 2-equivalent yellow coupler containing a halogen such as chlorine in the coupling position with the nitrogen-containing heterocyclic compound that supplies the splittable group, in the presence of base and in the further presence of hexamethylphosphoric acid triamide as solvent.

Inventors

  • 👤 Immo Boie
  • 👤 Dieter Lowski

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-26 15:43
CPC Classifications
C; C07; C07D; C07D231/00; C07D231/02; C07D231/10; C07D231/14; C07D231/38; C07D231/12; C07D231/16; C07D231/18; C07D231/40; C07D231/42; C07D233/00; C07D233/54; C07D233/56; C07D233/66; C07D233/90; C07D233/91; C07D233/92; C07D249/00; C07D249/02; C07D249/04; C07D249/06; C07D249/08; G; G03; G03C; G03C7/00; G03C7/30; G03C7/305; G03C7/30511; G03C7/30517; G03C7/30535

Claims Analysis

Total Claims: 5
Claim 1
Independent Claim 85 words
In a light sensitive color photographic material containing at least one silver halide emulsion layer and a 2-equivalent yellow coupler having an activated open-chain ketomethylene coupler structure in which one hydrogen of the methylene group is substituted by a nitrogen of a heterocyclic group which group is photographically relatively inert except that it is split off during chromogenic development, the improvement according to which the splittable group is a monocyclic pyrrole, 1,2-diazole, 1,3-diazole or 1,2,3-triazole group attached to the coupling position of the yellow coupler.
Claim 2
Dependent Claim 85 words
In a light sensitive color photographic material containing at least one silver halide emulsion layer and a 2-equivalent yellow coupler having an activated open-chain ketomethylene coupler structure in which one hydrogen of the methylene group is substituted by a nitrogen of a heterocyclic group which group is photographically relatively inert except that it is split off during chromogenic development, the improvement according to which the splittable group is a monocyclic pyrrole, 1,2-diazole, 1,3-diazole or 1,2,3-triazole group attached to the coupling position of the yellow coupler.
Claim 3
Dependent Claim 13 words
The combination of claim 1 wherein the diazole group is an imidazole group.
Claim 4
Dependent Claim 12 words
The combination of claim 2 wherein the imidazole group is methoxycarbonyl substituted.
Claim 5
Dependent Claim 18 words
The combination of claim 1 in which the yellow coupler is selected from the class consisting of ##STR12##

References Cited (Backward Citations)

US3617291A Cited
US3770436A Cited
US3808945A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1980-09-19 1981-03-21 1981-09-20 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1984-09-19 1985-03-21 1985-09-20 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1988-09-19 1989-03-21 1989-09-20 $7700.00 Window Closed / Lapsed

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