Hardening fixer for photographic silver halide material
AssigneeAgfa-Gevaert
InventorsMarcel Robert Fierens, Renaat Frans Heylen
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Abstract
A hardening fiber composition for use in the processing of photographic silver halide elements is described which contains a 1-hydroxy-alkylidene diphosphonic acid the alkylidene group of which contains from 2 to 5 C-atoms.
Claims6
A hardening fixer composition for use in the processing of photographic silver halide elements, comprising a thiocyanate or thiosulphate silver halide solvent and an aluminum hardener, wherein the said fixer composition also contains a 1-hydroxy-alkylidene diphosphonic acid of the formula:
- ##STR2## n being 0, 1, 2, or 3.
In a method of processing an imagewise exposed photographic silver halide element comprising the steps of developing by means of a developer comprising a silver halide developing agent and treating the developed element with a hardening fixer comprising an aluminum hardener and a thiocyanate or thiosulphate silver halide solvent, the improvement which comprises using in the fixer composition a 1-hydroxy-alkylidene diphosphonic acid of the formula:
- ##STR3## n being 0, 1, 2, or 3.
Dependencies are inferred from the claim text.