RELATIVE DISSOLUTION RATES OF SILVER-HALIDE CRYSTALS BY KINETIC CALORIMETRY

The relative rates of dissolution of silver halide crystals in a liquid photographic emulsion were measured from the rate of temperature change in a continuously flowing system after mixing of the fixing solution and photographic emulsion. The fixing solution was composed of thiosulfate, sulfite, and bisulfite ions, and the dissolution of silver halide by complex ion formation was carried out at 55 degree C. It was determined that the rate of dissolution depends on the iodide content of the silver halide, crystal size (surface area), and temperature. Phenylmercaptotetrazole added to the photographc emulsion significantly decreased the rate of dissolution at a level of 3 mg/g of silver. Chemical ripening, back-addition of gelatin, and exposure to light did not affect the rate.