Direct positive emulsions containing fogged, monodispersed silver halide grains having more than 10 mile % iodide
AssigneeAgfa-Gevaert
InventorsWilly Joseph Vanassche, Herman Alberik Pattyn, Otto Lapp, Sieghart Klotzer, Erik Moisar
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Abstract
Direct positive silver halide emulsions are provided which contain fogged homodisperse silver halide grains having a silver iodide content of more than 10 mole % and at most 20 mole % relative to the total amount of silver halide. These emulsions have higher sensitivity than corresponding fogged emulsions with less silver iodide content.
Claims13
Photographic material comprising at least one layer of a direct-positive radiation-sensitive emulsion having high sensitivity and good maximum density containing fogged homodisperse silver halide grains wherein at least 95% by weight of the silver halide grains of the emulsion have a diameter which is within about 40% of the mean grain diameter and wherein the silver halide of the grains has a silver iodide content of more than 10 mole % and at most about 20 mole % relative to the total amount of silver halide.
Method of producing direct-positive images, which comprises image-wise exposing and subsequently surface developing a direct positive material containing fogged homodisperse silver halide grains wherein at least 95% by weight of the silver halide grains of the emulsion have a diameter which is within about 40% of the mean grain diameter and wherein the silver halide of the grains has a silver iodide content of more than 10 mole % and at most about 20 mole % relative to the total amount of silver halide.
Dependencies are inferred from the claim text.