Acceleration of silver removal by thioether compounds
AssigneeEastman Kodak Company
InventorsEric R. Schmittou, Jacob J. Hastreiter, Jr., Stuart T. Gordon
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Abstract
This invention provides a process for removal of silver halide from a silver halide photographic recording material by a processing solution with fixing ability (a fixer) containing thiosulfate as a fixing agent conducted in the presence of a thioether compound incorporated within a fixer formulation. It further provides a fixer formulation for use in said process. The fixer contains a maximum ammonium ion concentration of 0.9M.
Claims21
A process for fixing an exposed and developed silver halide-based color photographic material,
- said process comprising fixing said material with a fixer comprising thiosulfate and a fix rate-accelerating amount of a thioether compound, said process being characterized by being conducted:
- a) in the presence of a fix rate-retarding amount of iodide, and
- b) in the substantial absence of an iron chelate bleaching agent;
- wherein the ammonium concentration in said fixer is less than 0.9 mole per liter.
A process for fixing an exposed and developed silver halide-based non-spectrally sensitized black-and-white photographic material;
- said process comprising fixing said material with a fixer comprising thiosulfate and a fix rate accelerating amount of a thioether compound, said process being characterized by being conducted
- in the presence of a fix rate-retarding amount of iodide;
- wherein the ammonium concentration in said fixer is less than 0.9 mole per liter.
A fixer suitable for fixing exposed, and developed silver halide-based photographic material in the presence of a rate-retarding amount of iodide, said fixer comprising a thiosulfate and a thioether compound in an amount such that the rate of fixing with said fixer is greater than the sum of the rates achieved when said thioether compound and said thiosulfate are each used alone, in said amounts, with said rate-retarding amount of iodide, said fixer containing substantially no iron chelate bleaching agent and having an ammonium concentration less than 0.9M.
Dependencies are inferred from the claim text.