Silver halide emulsion and silver halide photographic light sensitive material
AssigneeKonica Corporation
InventorHiroaki Ando
Life of this patent
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Abstract
A silver halide emulsion is disclosed, comprising tabular silver halide grains, wherein the tabular grains contain 50 mol % or more bromide, based on total silver and have parallel (111) major faces and a mean aspect ratio of not less than 2; and the tabular grains each comprising a central region accounting for at least 50% of the (111) major face, and an annular band accounting for not more than 5% of the (111) major face and containing not less than 0.05 mol % iodide and not more than 50 mol % chloride, based on silver forming the annular band.
Claims9
A silver halide emulsion comprising tabular silver halide grains, wherein said tabular grains contain 50 mol % or more bromide, based on total silver and have parallel (111) major faces and a mean aspect ratio of not less than 2;
- and the tabular grains each comprising a central region accounting for at least 50% of the (111) major face, and an annular band accounting for not more than 5% of the (111) major face and containing not less than 0.05 mol % iodide and not more than 50 mol % chloride, based on silver forming the annular band.
A method of preparing a silver halide emulsion comprising tabular grains, wherein said tabular grains contain 50 mol % or more bromide, based on total silver and have parallel (111) major faces and a mean aspect ratio of not less than 2;
- and the tabular grains each comprising a central region accounting for at least 50% of the (111) major face, and an annular band accounting for not more than 5% of the (111) major face and containing not less than 0.05 mol % iodide and not more than 50 mol % chloride, based on silver forming the annular band, the method comprising the steps of:
- (a) reacting silver and a halide salts in solution to form tabular grains substantially not containing chloride,
- (b) reacting a silver salt solution and a chloride containing halide salt solution to form the annular band containing chloride and
- (c) adding a water soluble iodide salt to perform conversion of at least a part of the chloride to iodide.
Dependencies are inferred from the claim text.