Silver halide photographic material comprising two kinds of monodisperse emulsions differing in mean grain size
AssigneeFuji Photo Film Co., Ltd.
InventorKen-ichi Kuwabara
Life of this patent
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Abstract
A silver halide photographic material comprising at least one negative type silver halide emulsion layer coated on a support, said emulsion comprising two kinds of monodisperse emulsions each having a means grain sizes of not more than 0.5 micron and, differing in mean grain size from each other at least by 0.1 micron, and said photographic material further comprising a hydrazine derivative in at least one photographic layer, whereby negative images of high density and very high contrast can be obtained with a high photographic speed and without black spots.
Claims20
A silver halide photographic material comprising at least one negative type silver halide emulsion layer coated on a support, said emulsion comprising two kinds of monodisperse emulsions each having a mean grain size of not more than 0.5 micron and, differing in mean grain size from each other at least by 0.1 micron, and said photographic material further comprising a hydrazine derivative in at least one photographic layer, wherein one of said monodisperse emulsions has a mean grain size of not more than 0.3 micron and the other has a mean grain size of at least 0.3 micron, wherein the fraction of the finer-grained silver halide ranges from 40 to 90% by weight based on the weight of the total amount of silver halide in the monodisperse emulsions, wherein said hydrazine derivative is a compound selected from the group consisting of compounds represented by formulae (I) and (II):
- R.sub.1 --NHNH--G--R.sub.2 (I)
- wherein R.sub.1 represents an aliphatic group, an aromatic group or a saturated heterocyclic group;
- R.sub.2 represents a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted alkoxy group, or a substituted or unsubstituted aryloxy group;
- and G represents a carbonyl group, a sulfonyl group, a sulfoxy group, a phosphoryl group, or a N-substituted or unsubstituted iminomethylene group, and ##STR6## wherein;
- "Acyl" is an acyl group,
- "Ar" is an aryl group,
- R.sup.1 represents a hydrogen atom and sulfinic acid radical substituent, and
- R.sup.2 is chosen to be a sulfinic acid radical substituent when R.sup.1 is a hydrogen atom and a hydrogen atom when R.sup.1 is a sulfonic acid radical, wherein said hydrazine derivative is present in a contrast-enhancing amount.
Dependencies are inferred from the claim text.