Silver halide emulsion
AssigneeKonica Corporation
InventorKoichiro Kuroda
Life of this patent
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Abstract
A silver halide emulsion is disclosed, comprising silver halide grains having a chloride content of not less than 90 mol % and internally doped with an iridium compound (A) and a compound (B) forming a stronger electron trap than said iridium compound (A), the silver halide grains meeting the following requirement: 10<X<1000 and 0<Y≦X wherein X represents an average number of molecules of said iridium compound (A) contained per grain and Y represents an average number of molecules of said compound (B) contained per grain.
Claims13
A silver halide emulsion comprising silver halide grains, wherein the silver halide grains each have a chloride content of not less than 90 mol % and are internally doped with an iridium compound (A) and a compound (B) forming a stronger electron trap than said iridium compound (A), the silver halide grains meeting the following requirement:
- 10<X<1000 and 0<Y≦X
- wherein X represents an average number of molecules of said iridium compound (A) contained per grain and Y represents an average number of molecules of said compound (B) contained per grain, and wherein said compound (B) is doped in an interior region which is the same as or internal to an interior region doped with said compound (A) and the silver halide grains each have at least a region doped with said iridium compound (A) alone, a region doped with said compound (B) alone and a region doped with neither said iridium compound (A) nor said compound (B) within the grain, and each of the region doped with said iridium compound (A) and the region doped with said compound (B) accounting for a least 10% by volume of the grain.
A method for preparing a silver halide emulsion comprising silver halide grains, each having a chloride content of not less than 90 mol % and being internally doped with an iridium compound (A) and a compound (B) forming a stronger electron trap than said iridium compound (A),
- the method comprising forming silver halide grains by adding a sliver salt and a halide salt to an aqueous solution containing a dispersing medium, and further comprising adding an iridium compound (A) and adding a compound (B) during forming the silver halide grains, wherein the silver halide grains meet the following requirement:
- 10<X<1000 and 0<Y≦X
- wherein X represents an average number of molecules of said iridium compound (A) contained per grain and Y represents an average number of molecules of said compound (B) contained per grain, and wherein each of the addition of said iridium compound (A) and addition of said compound (B) are independently carried out over a period of adding a least 10% of the total amount of the silver salt.
Dependencies are inferred from the claim text.