Silver halide photographic material and very high contrast negative image-forming process using same
AssigneeFuji Photo Film Co., Ltd.
InventorsNobuaki Inoue, Senzo Sasaoka, Toshiro Takahashi
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Abstract
A silver halide photographic material having on a support at least one silver halide emulsion layer is disclosed, wherein the silver halide emulsion layer comprises a silver halide emulsion containing an oxidizing agent added thereto before chemical ripening of the emulsion, and the silver halide emulsion or a hydrophilic colloid layer contains a hydrazine derivative.
Claims17
A silver halide photographic material which yields a gamma of 10 or higher having on a support at least one silver halide emulsion layer, wherein the silver halide emulsion layer comprises a silver halide emulsion containing an oxidizing agent for the at least one silver halide emulsion added thereto before chemical ripening of the emulsion, and the silver halide emulsion layer or a hydrophilic colloid layer contains a hydrazine derivative added after chemical sensitization and represented by general formula (I):
- R.sub.1 .dbd.NHNH.dbd.CHO (I)
- wherein R.sub.1 represents an aliphatic group or an aromatic group, wherein the oxidizing agent is added to the silver halide emulsion after physical ripening which is then subjected to oxidation, and water-washing followed by chemical sensitization.
A process for forming a high contrast negative image having a gamma value of 10 or higher, which comprises imagewise exposing a silver halide photographic material having on a support at least one silver halide emulsion layer, in which the silver halide emulsion layer comprises a silver halide emulsion containing an oxidizing agent for the at least one silver halide emulsion added thereto before chemical ripening of the emulsion and the silver halide emulsion or a hydrophilic colloid layer contains a hydrazine derivative added after chemical sensitization and represented by general formula (I):
- R.sub.1 .dbd.NHNH.dbd.CHO (I)
- wherein R.sub.1 represents an aliphatic group or an aromatic group, and then developing the photographic material with a developer containing at least 0.15 mole/liter of a sulfite ion and having a pH of 10.5 to 12.3, wherein the oxidizing agent is added to the silver halide emulsion after physical ripening which is then subjected to oxidation and water-washing followed by chemical desensitization.
Dependencies are inferred from the claim text.