Claims
- 1. A silver halide photographic emulsion, which comprises silver halide grains having been spectrally sensitized with sensitizing dyes that are multilayer adsorbed onto a surface of said silver halide grains,wherein the sensitizing dyes comprise an anionic cyanine dye and a cationic cyanine dye, the silver halide grains are tabular grains having an aspect ratio of 10 or more and said grains have a halogen composition of the outermost surface such that iodide content is 0.1 mol % or more.
- 2. The silver halide photographic emulsion according to claim 1, wherein the silver halide grains have an aspect ratio of 20 or more.
- 3. The silver halide photographic emulsion according to claim 1, wherein 30% or more of the total addition amount of the sensitizing dyes is the anionic dye and 30% or more of the total addition amount of the sensitizing dyes is the cationic cyanine dye.
- 4. A multilayer color photographic material, which comprises a silver halide photographic emulsion according to claim 1.
- 5. A silver halide photographic emulsion, which comprises silver halide grains having been spectrally sensitized with sensitizing dyes that are multilayer adsorbed onto a surface of said silver halide grains by adding an anionic cyanine dye and a cationic cyanine dye separately,wherein the later-added dye satisfies at least one of the following conditions: a) the fluorescent yield of the later-added dye in a gelatin dry film is 0.5 or more; b) the reduction potential of the later-added dye is equal to or less than that of the dye added first; and/or c) the oxidation potential of the later-added dye is less by 0.01 V or more than that of the dye added first.
- 6. The silver halide photographic emulsion according to claim 5, wherein said later-added dye satisfies at least two of said conditions.
- 7. The silver halide photographic emulsion according to claim 5, wherein said later-added dye satisfies the conditions b) and c).
- 8. A multilayer color photographic material, which comprises a silver halide photographic emulsion according to claim 5.
- 9. A method for forming a spectrally sensitized silver halide photographic emulsion, comprising,a) adding a part of spectral sensitizing dyes to silver halide grains, whereby said dyes adsorb on a surface of the grains; b) subjecting the silver halide grains to chemical sensitization; and c) adding the remaining part of the spectral sensitizing dyes to the chemically sensitized silver halide grains, whereby said dyes are multilayer adsorbed onto a surface of the grains, wherein said sensitizing dyes comprise an anionic cyanine dye and a cationic cyanine dye.
- 10. The method according to claim 9, wherein 30% or more of the total addition amount of the sensitizing dyes is the anionic dye and 30% or more of the total addition amount of the sensitizing dyes is the cationic cyanine dye.
- 11. The method according to claim 9, wherein the silver halide grains are tabular grains having an aspect ratio of 20 or more.
- 12. The method according to claim 9, wherein the silver halide grains have a halogen composition of the outermost surface such that iodide content is 0.1 mol % or more.
- 13. The method according to claim 9, wherein the chemical sensitization is conducted using a gold sensitizer, a sulfur sensitizer and a selenium sensitizer.
- 14. A silver halide photographic emulsion, having been prepared by the method according to claim 9.
- 15. A multilayer color photographic material, which comprises a silver halide photographic emulsion having been prepared by the method according to claim 9.
Priority Claims (2)
Number |
Date |
Country |
Kind |
8-282595 |
Oct 1996 |
JP |
|
8-348524 |
Dec 1996 |
JP |
|
Parent Case Info
This is a divisional application of U.S. patten application No. 09/739,884, filed Dec. 20, 2000, which is a continuation of application No. 09/469,226, filed Dec. 22, 1999, now U.S. Pat. No. 6,180,332 B1, which is a continuation of application No. 08/956,027, filed Oct. 22, 1997, now issued as U.S. Pat. No. 6,117,629, the disclosures of which are incorporated herein by reference.
US Referenced Citations (11)
Continuations (2)
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Number |
Date |
Country |
Parent |
09/469226 |
Dec 1999 |
US |
Child |
09/739884 |
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US |
Parent |
08/956027 |
Oct 1997 |
US |
Child |
09/469226 |
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US |