Hybrid graphic arts films with reduced occurrence of pepper fog
AssigneeMinnesota Mining and Manufacturing Company
InventorRichard C. Cotner
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Abstract
The present invention provides a photographic element developed in the presence of a hydrazide which displays high contrast but low levels of pepper fog. The novel silver halide photographic elements comprise, in at least one layer of the element, a pepper reducing agent. The pepper reducing agent of this invention is a compound having at least one nitrogen containing, heterocyclic ring group and at least one carbonyl group in or attached to said ring. The pepper reducing agents preferably are selected from the group containing 2,5-piperazinediones; glycol urils; 2,3-pyrazinedicarboxamides; 3-iminoisoindolinones; or glutarimides.
Claims13
A silver halide photographic film comprising a substrate and a photographic emulsion coated on the substrate, wherein the emulsion comprises a hydrazine, silver halide grains, and a pepper reducing agent selected from the group consisting of:
- 2,5-piperizinediones;
- glycol urils;
- 3-iminoisoindolinones;
- or glutarimides, wherein said photographic film is a black and white photographic film.
A silver halide photographic film comprising a substrate and a photographic emulsion coated on the substrate, wherein the emulsion comprises a hydrazine, silver halide grains, and a pepper reducing agent which is present in amounts 0.003 to 0.015 moles per mole of silver, and is represented by the formula:
- ##STR17## wherein, R.sub.1 and R.sub.2 independently are hydrogen, alkyl or cyclic alkyl groups or R.sub.1 and R.sub.2 taken together form an aromatic ring.
A photographic emulsion comprising a hydrophilic colloid binder, negative-acting silver halide grains, a hydrazine, and a pepper reducing agent selected from the group consisting of:
- 2,5-piperizinediones;
- glycol urils;
- 3-iminoisoindolinones;
- or glutarimides, wherein said photograhpic emulsion is a black and white photographic emulsion.
A photographic emulsion comprising a hydrophilic colloid binder, negative-acting silver halide grains, a hydrazine, and a pepper reducing agent wherein said pepper reducing agent is present in amounts from 0.003 to 0.015 moles per mole Ag and is represented by the formula:
- ##STR22## wherein, R.sub.1 and R.sub.2 independently are hydrogen, alkyl or cyclic alkyl groups or R.sub.1 and R.sub.2 taken together form an aromatic ring.
Dependencies are inferred from the claim text.