Pre-fogged direct-positive silver halide photographic light-sensitive material and method of preparing emulsion for the same
AssigneeFuji Photo Film Co., Ltd.
InventorsIsao Oyagi, Shingo Nishiyama, Nobuaki Inoue
Life of this patent
Estimating the term…
Abstract
A direct-positive silver halide light-sensitive material comprising a support having thereon at least one pre-fogged light-sensitive silver halide emulsion layer, wherein the light-sensitive material comprises a specific onium salt compound in the emulsion layer or a hydrophilic protective colloid layer adjacent thereto. Also disclosed is a method of preparing a pre-fogged light-sensitive silver halide emulsion for use in the light-sensitive material.
Claims5
A direct-positive silver halide photographic light-sensitive material which comprises a support having thereon at least one pre-fogged light-sensitive silver halide emulsion layer, wherein the light-sensitive material contains at least one compound represented by the following formula (A), (B-1), (B-2) or (B-3) in the emulsion layer or a hydrophilic protective colloid layer adjacent to the emulsion layer;
- ##STR11## wherein R.sub.1, R.sub.2 and R.sub.3 each represents an unsubstituted or substituted alkyl, cycloalkyl, aryl, alkenyl, cycloalkenyl or heterocyclic group, m represents an integer, L represents an m-valent organic group which is attached to the P atom via its carbon atom, n represents an integer of 1, 2 or 3, and X is an n-valent anion which may be attached to L;
- ##STR12## wherein A represents an organic group for completing a heterocyclic ring, B and C each represents a divalent group, R.sub.1 and R.sub.2 each represents an alkyl group or an aryl group, R.sub.3 and R.sub.4 each represents a hydrogen atom or a substituent group, R.sub.5 represents an alkyl group, and X represents an anion or becomes unnecessary when an inner salt is formed.
A method of preparing a pre-fogged direct-positive silver halide emulsion which comprises the steps of:
- (a) forming silver halide grains;
- and
- (b) thereafter fogging the grain surface of said formed silver halide grains with a reducing agent to produce silver nuclei,
- wherein at least one compound represented by the following formula (A), (B-1), (B-2) or (B-3) is used:
- ##STR13## wherein R.sub.1, R.sub.2 and R.sub.3 each represents an unsubstituted or substituted alkyl, cycloalkyl, aryl, alkenyl, cycloalkenyl or heterocyclic group, m represents an integer, L represents an m-valent organic group which is attached to the P atom via its carbon atom, n represents an integer of 1, 2 or 3, and X is an n-valent anion which may be attached to L;
- ##STR14## wherein A represents an organic group for completing a heterocyclic ring, B and C each represents a divalent group, R.sub.1 and R.sub.2 each represents an alkyl group or an aryl group, R.sub.3 and R.sub.4 each represents a hydrogen atom or a substituent group, R.sub.5 represents an alkyl group, and X represents an anion or becomes unnecessary when an inner salt is formed.
Dependencies are inferred from the claim text.