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AssigneeAgfa-Gevaert
InventorsSieghart Klotzer, Erik Moisar
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A photographic material for producing direct-positive photographic images with at least one silver halide emulsion layer containing unfogged heterodisperse silver halide grains with a core which consists predominantly of silver bromide and a localised phase with a high silver chloride content of at least 20 mols-%, the total concentration of silver chloride, based on the total silver halide content of the grain, is less than 30 mols-%, and at least 10% by weight of the silver halide grains have a diameter which deviates by at least 40% from the average grain diameter in which the silver halide grains are not or only slightly chemically sensitised on the surface.
A photographic material for producing direct positive photographic images with at least one silver halide emulsion layer containing unfogged silver halide grains, in which the silver halide grains have a layered grain structure wherein at least 10% of the silver halide grains of the emulsion have a grain diameter which deviates by at least 40% from the average grain diameter and are substantially not chemically sensitized on the surface, wherein the improvement comprises the silver halide grains of the silver halide emulsion contain a core which consists predominantly of silver bromide and a localised phase with a high silver chloride content of at least 20 mols-%, the total concentration of silver chloride, based on the total silver halide content of the grain, is less than 30 mols-%, and the silver halide grains are on the surface not or only to such an extent chemically sensitized that they are developable after exposure stepwise for 1/100 th to 1 second and developed for 3 minutes at 20.degree.C in the internal developer of the following composition:
The process for the production of direct positive photographic images comprising the steps of imagewise exposing a photographic material comprising at least one light sensitive silver halide emulsion layer which contains unfogged silver halide grains with a layered grain structure wherein at least 10% of the silver halide grains of the emulsion have a grain diameter which deviates by at least 40% from the average grain diameter and are substantially not chemically sensitized on the surface and fogging development of the exposed layer wherein the improvement comprises the silver halide grains of the emulsion contain a core which consists predominantly of silver bromide and a localised phase with a high silver chloride concentration, based on the total silver halide content of the grain, is less than 30 mols-%, and the silver halide grains are on the surface not or only to such an extent chemically sensitized that they are developable after exposure stepwise for 1/100 th to 1 second and developed for 3 minutes at 20.degree.C in the internal developer of the following composition:
Dependencies are inferred from the claim text.