Photographic fine grain silver halide materials
Abstract
Abstract A method of preparing a photographic fine-grain silver halide emulsion is described wherein precipitation of the silver halide occurs in the presence of a compound corresponding to the formula: WHEREIN Z represents the atoms necessary to complete an imidazole, benzimidazole or naphthimidazole nucleus; Q is sulphur or selenium; R is hydrogen, C1-C4 alkyl or aryl, A is alkylene, which may be interrupted by hetero atoms, -S-alkylene which may be interrupted by hetero atoms, or arylene and X is alkyl, alkenyl or aryl or A and X together with Q represent the atoms necessary to complete a non-nitrogen containing heterocycle. By the presence of these compounds during precipitation of the silver halide homogeneous Lippmann-emulsions can be prepared with an average grain-size of less than 50 nm.
Inventors
- 👤 Herman Adelbert Philippaerts
- 👤 Robert Joseph Pollet
- 👤 Jozef Frans Williems
- 👤 Frans Henri Claes
Bibliographic Details
Claims Analysis
Total Claims: 3References Cited (Backward Citations)
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