Claims
- 1. A silver halide emulsion comprising at least one compound selected from the following four types of electron-releasing compounds, namely:
(Type 1) an electron-releasing compound capable of undergoing a one-electron oxidation to thereby form a one-electron oxidation product thereof, the one-electron oxidation product capable of releasing further two or more electrons accompanying a subsequent bond cleavage reaction; (Type 2) an electron-releasing compound capable of undergoing a one-electron oxidation to thereby form a one-electron oxidation product thereof, the one-electron oxidation product capable of releasing further one electron accompanying a subsequent bond cleavage reaction, and the one-electron oxidation product having, in its molecule, two or more adsorptive groups acting on silver halides; (Type 3) an electron-releasing compound capable of undergoing a one-electron oxidation to thereby form a one-electron oxidation product thereof, the one-electron oxidation product capable of releasing further one or more electrons after going through a subsequent bond forming process; and (Type 4) an electron-releasing compound capable of undergoing a one-electron oxidation to thereby form a one-electron oxidation product thereof, the one-electron oxidation product capable of releasing further one or more electrons after going through a subsequent intramolecular ring cleavage reaction.
- 2. The silver halide emulsion according to claim 1, wherein said at least one compound is a compound which undergoes a one-electron oxidation induced by exposure of the silver halide emulsion to light.
- 3. The silver halide emulsion according to claim 1, wherein said at least one compound is represented by any of the following general formulae (A), (B), (C), (D), (E), (F), (1), (2) and (3):
- 4. The silver halide emulsion according to claim 1, wherein said electron-releasing compounds of types 1, 3 and 4 are compounds each having in its molecule at least one adsorptive group acting on silver halides or at least one partial structure of a spectral sensitizing dye.
- 5. The silver halide emulsion according to claim 1, wherein each of said compounds is a compound having in its molecule two or more mercapto groups as a partial structure thereof.
- 6. The silver halide emulsion according to claim 1, wherein each of said compounds has a nitrogen-containing heterocyclic group that is substituted with two or more mercapto groups, as the adsorptive group.
- 7. The silver halide emulsion according claim 3, wherein said split-off group of each of the general formulas (A) to (F) and (1) to (3) is a carboxyl group or salt thereof, or hydrogen atom.
- 8. The silver halide emulsion according to claim 3, wherein said compound of general formula (D) is represented by any of the following general formulae (D-1) to (D-4):
- 9. The silver halide emulsion according to claim 1, wherein an oxidation potential with respect to said first electron is 0 V or more and 1.4 V or less.
- 10. The silver halide emulsion according claim 1, wherein said one-electron oxidation product that is produced after said one-electron oxidation of said compounds of Types 1 to 4 has an oxidation potential of −0.7 V or less.
- 11. The silver halide emulsion according to claim 1, wherein silver halide grains contained in said silver halide emulsion comprise tabular grains having an aspect ratio of 5 or more.
- 12. A silver halide emulsion having been chemically sensitized by at least one compound selected from the following four types of electron-releasing compounds:
(Type 1) an electron-releasing compound capable of undergoing a one-electron oxidation to thereby form a one-electron oxidation product thereof, the one-electron oxidation product capable of releasing further two or more electrons accompanying a subsequent bond cleavage reaction; (Type 2) an electron-releasing compound capable of undergoing a one-electron oxidation to thereby form a one-electron oxidation product thereof, the one-electron oxidation product capable of releasing further one electron accompanying a subsequent bond cleavage reaction, and the one-electron oxidation product having, in its molecule, two or more adsorptive groups acting on silver halides; (Type 3) an electron-releasing compound capable of undergoing a one-electron oxidation to thereby form a one-electron oxidation product thereof, the one-electron oxidation product capable of releasing further one or more electrons after going through a subsequent bond forming process; and (Type 4) an electron-releasing compound capable of undergoing a one-electron oxidation to thereby form a one-electron oxidation product thereof, the one-electron oxidation product capable of releasing further one or more electrons after going through a subsequent intramolecular ring cleavage reaction.
- 13. A silver halide photographic lightsensitive material comprising said silver halide emulsion according to claim 1.
- 14. The silver halide photographic lightsensitive material according to claim 13, wherein said silver halide emulsion is chemically sensitized by at least one compound selected from said electron-releasing compounds of Types 1 to 4.
- 15. The silver halide photographic lightsensitive material according to claim 13, further comprising at least one reducing compound.
- 16. The silver halide photographic lightsensitive material according to claim 14, further comprising at least one reducing compound.
Priority Claims (4)
Number |
Date |
Country |
Kind |
2001-234048 |
Aug 2001 |
JP |
|
2001-234075 |
Aug 2001 |
JP |
|
2001-250679 |
Aug 2001 |
JP |
|
2001-272137 |
Sep 2001 |
JP |
|
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is based upon and claims the benefit of priority from the prior Japanese Patent Applications No. 2001-234048, filed Aug. 1, 2001; No. 2001-234075, filed Aug. 1, 2001; No. 2001-250679, filed Aug. 21, 2001; and No. 2001-272137, filed Sep. 7, 2001, the entire contents of all of which are incorporated herein by reference.