Preparation of photographic emulsion containing narrow size distribution of octahedral silver halide grains sensitized with gold compound
Abstract
Abstract A PROCESS FOR PREPARING A SILVER HALIDE PHOTOGRAPHIC EMULSION HAVING A VERY NARROW DISTRIBUTION OF GRAIN SIZES AND A REDUCED FOG FORMATION ON BEING SENSITIZED WITH A GOLD-CONTAINING CHEMICAL SENSITIZER COMPRISING ADDING A WATER-SOLUBLE SILVER SALT SOLUTION AND A WATER-SOLUBLE ALKALI METAL HALIDE SOLUTION SIMULTANEOUSLY AND GRADUALLY TO AN AQUEOUS SOLUTION OF GELATIN WHILE MAINTAINING THE CONCENTRATION OF SILVER ION AT A CONSTANT VALUE WITHIN A RANGE OF 10**-6 TO 10**-10 MOL/LITER, REDUCING THE SILVER ION CONCENTRATION TO LESS THAN 1/2 THE PREVIOUS CONCENTRATION USED AFTER ADDING 1/20 TO 1/2 OF THE TOTAL SILVER SALT, CONTINUING THE ADDITION AT THIS CONCENTRATION, RINSING THE EMULSION FREE OF WATER-SOLUBLE SALTS, AND CHEMICALLY SENSITIZING THE EMULSION WITH A CHEMICAL SENSITIZER CONTAINING AT LEAST A GOLD COMPOUND IS DISCLOSED. PHOTOGRAPHIC ELEMENTS CONTAINING THE SILVER HALIDE EMULEION ARE ALSO DISCLOSED.
Inventors
- 👤 T Nagae
- 👤 T Shimada
- 👤 K Suzuki
Bibliographic Details
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