| abstract |
(57) Abstract: An improved performance of an ultrathin tabular grain emulsion is provided. SOLUTION: (1) Dispersion medium, (a) {111} major surface; (b) More than 70 mol% of silver bromide and at least 0.25 mol% iodide; (c) Flat plate exceeding 90% of projected area. Particles; (d) at least 0.7 μm average ECD, and (e) 0.07 μm Providing an ultrathin tabular grain host emulsion containing silver halide tabular grains having an average thickness of less than (2) sensitization of an ultrathin tabular grain emulsion having the steps of (2) chemical and spectral sensitization of said emulsion In the method, step (2), silver and halide ions, including iodide and chloride ions, are added to the ultrathin tabular grain host emulsion to provide up to 50% of the tabular grain surface area and the halogens that form the epitaxial junction. Precipitate the silver halide protrusions, The protrusions have (a) a homomorphic face-centered cubic crystal structure, (b) a chloride ion concentration that is at least 10 mol% higher than that of tabular grains, (c) Includes increased iodide concentration due to iodide ion addition. |