EP0368356A1

EP0368356A1 - Silver halide color photographic material

Info

Publication number: EP0368356A1
Application number: EP89120915A
Authority: EP
Inventors: Koukichi Waki
Original assignee: Fuji Photo Film Co Ltd
Current assignee: Fujifilm Holdings Corp
Priority date: 1988-11-11
Filing date: 1989-11-10
Publication date: 1990-05-16
Also published as: JPH02131233A

Abstract

A silver halide color photographic material having on a support hydrophilic colloidal layers containing at least one light-sensitive silver halide emulsion layer and at least one light-insensitive layer, one of the silver halide emulsion layers being spectrally sensitized with a compound represented by the following general formula (I):

wherein Z represents an oxygen atom or a sulfur atom; R₁ and R₂ each represents an unsubstituted or substituted alkyl group; V₁, V₂, V₃, V₄, V₅, V₆, V₇ and V₈ each represents a hydrogen atom, a halogen atom, an alkyl group, an acyl group, an acyloxy group, an alkoxycarbonyl group, a carbamoyl group, a sulfamoyl group, a carboxyl group, a cyano group, a hydroxyl group, an amino group, an acylamino group, an alkoxy group, an alkylthio group, an alkylsulfonyl group, a sulfonic acid group or an aryl group, provided that any two adjacent groups among V₁ to v₈ do not form a condensed ring by combining with each other, and when the Hammett's σ_p value of V_i (i = 1 to 8) is taken as σ_pi (i = 1 to 8), and Y is defined as Y = σ_p1 + σ_p2 + σ_p3 + σ_p4 + σ_p5 + σ_p6 + σ_p7 + σ_p8, Y ≦ -0.08 in the case of Z = oxygen atom, while Y ≦ -0.15 in the case of Z = sulfur atom; X represents a counter ion for charge balancing; and n represents the number of counter ions for rendering the total charge of the compound neutral; and additionally containing an effective amount of a water-soluble bromide; and which material further contains at least one dye represented by the following general formula (II) in either a light-sensitive or light-insensitive constituent layer provided that when the dye of general formula (II) wherein n is 2 is incorporated therein, the amount thereof is in a coverage of at least 1 x 10⁻⁵ mol/m²;

wherein L₁, L₂ and L₃ each represents an unsubstituted or substituted methine group; Q represents an aryl group containing at least one sulfo or carboxyl group; R₃ and R₄ each represents -COR₅, -COOR₅, -CN, or -CF₃; R₅ and R₆ each represents a hydrogen atom, an unsubstituted or substituted alkyl group, or an unsubstituted or substituted aryl group; m represents 0, 1, 2, or 3; n represents 0, 1, or 2; and M represents K or Na.

Description

FIELD OF THE INVENTION

This invention relates to a silver halide color photographic material and, more particularly, to a silver halide color photographic material excellent in sharpness of color images formed therein and freshness keeping quality (or quality of hardly causing fluctuation in sensitivity upon long range storage in an unprocessed condition).

BACKGROUND OF THE INVENTION

A silver halide color photographic material produces color images in accordance with a three color process, in which the photographic material comprises silver halides sensitized spectrally with sensitizing dyes, and contains a yellow-color forming coupler, a magenta-color forming coupler and a cyan color-forming coupler in a blue-sensitive silver halide emulsion layer, a green-sensitive silver halide emulsion layer and a red-sensitive silver halide emulsion layer, respectively, and is subjected successively to imagewise exposure, a processing with a color developer containing a p-phenylenediamine derivative as a color developing agent, and a bleach-fix processing.
In order to enhance sharpness of color images, it has been generally carried out to dye photographic emulsions. In case of commercially available color print material, dyes are generally added in an amount of 1 × 10⁻⁵ mol/m² or less.
In most cases, layers to be dyed comprise a hydrophilic colloid, so dyeing of such layers is effected by incorporation of water-soluble dyes therein. These dyes have to satisfy the following requirements:

(1) They have to show spectral absorption proper for the end use purpose.
(2) They have to be inert from the viewpoint of photographic chemistry. That is to say, they ought not to produce any chemically undesirable influences upon properties of silver halide photographic emulsion layers, for example, not to lower the sensitivity, not to fade latent images, or not to cause fog.
(3) They have to be decolored, or removed by dissolution in the course of photographic processing in order not to leave any harmful coloration on the processed photographic materials.

Many efforts have been made to find dyes fulfilling the above-described requirements, and those cited below have come to be known. Specifically, there can be given as examples oxonol dyes having a pyrazolone nucleus or a barbituric acid nucleus, as disclosed in British Patent 506,385, 1,177,429, 1,311,884, 1,338,799, 1,385,371, 1,467,214, 1,433,102 and 1,553,516, JP-A-48-85130 (the term "JP-A" as used herein refers to a "published unexamined Japanese patent application"), JP-A-49-114420, JP-A-55-161233, JP-A-59-111640, U.S. Patents 3,247,127, 3,469,985 and 4,078,933; other oxonol dyes as disclosed in U.S. Patents 2,533,472 and 3,379,533, and British Patent 1,278,621; azo dyes as disclosed in British Patents 575,691, 680,631, 599,623, 786,907, 907,125 and 1,045,609, U.S. Patent 4,255,326, JP-A-59-211043; azomethine dyes as disclosed in JP-A-50-100116, JP-A-54-118247, and British Patents 2,014,598 and 750,031; anthraquinone dyes disclosed in U.S. Patent 2,865,752; arylidene dyes as disclosed in U.S. Patents 2,538,009, 2,688,541 and 2,538,008, British Patents 584,609 and 1,210,252, JP-A-50-40625, JP-A-51-3623, JP-A-51-10927, JP-A-51-118247, JP-B-48-3286 (the term "JP-B" as used herein refers to an "examined Japanese patent publication"), JP-B-59-37303; styryl dyes as disclosed in JP-B-28-3082, JP-B-44-16594 and JP-B-59-28898; triarylmethane dyes as disclosed in British Patent 446,583 and 1,335,422, JP-A-59-228250; merocyanine dyes as disclosed in British Patents 1,075,653, 1,153,341, 1,284,730, 1,475,228 and 1,542,807; and cyanine dyes as disclosed in U.S. Patents 2,843,486 and 3,294,539.
Among these dyes, oxonol dyes having two pyrazolone nuclei have been prevailingly used as useful dyes for dyeing photosensitive materials because they have the property of being decolored during development with a developer containing a sulfite, and hardly produce bad influences upon photographic emulsions.
On the other hand, the coincidence between the wavelength region in which silver halide emulsions are spectrally sensitized and the wavelength region in which dyes absorb light constitutes an important factor in enhancing the sharpness of color images to be produced and, in case of color print, it is desirable that the wavelengths at which dyes absorb light should further coincide with the wavelengths at which light is absorbed by dyes of color images produced in the photograph-taking photosensitive material. Therefore, a great number of studies on spectral sensitizers for designing silver halide emulsions so as to have light sensitivities in respectively desired wavelength regions have so far been made.
As examples of spectral sensitizers, mention may be made of cyanine dyes and merocyanine dyes as described, e.g., in T.H. James, The Theory of the Photographic Process, 4th Edition, pp. 194-234, Macmillan Pub. Co., Inc. (1977); Research Disclosure (RD), 17643, pp. 23-24 (December, 1978); and RD, 18716, pp. 648-649 (November, 1979). However, these dyes cannot give full satisfaction to improvements in sharpness of color images and freshness keeping property of photographic materials.

SUMMARY OF THE INVENTION

Therefore, an object of this invention is to provide a silver halide color photographic material which is excellent in sharpness of color images, and suffers a slight change in sensitivity upon storage under high temperature and/or high humidity (that is, has an excellent freshness keeping property).
The above-described object of this invention is attained with a silver halide color photographic material which has on a support hydrophilic colloidal layers containing at least one light-sensitive silver halide emulsion layer and at least one one light-insensitive layer, one of the silver halide emulsion layers being sensitized spectrally with a compound represented by the following general formula (I), and contains an effective amount of a water-soluble bromide, and which material further contains at least one dye represented by the following general formula (II) in either a light-sensitive or light-insensitive constituent layer provided that when the dye of general formula (II) wherein n is 2 is incorporated therein, the amount thereof is in a coverage of at least 1 x 10⁻⁵ mol/m²:
wherein Z represents an oxygen atom or a sulfur atom; R₁ and R₂ each represents an unsubstituted or substituted alkyl group; V₁, V₂, V₃, V₄, V₅, V₆, V₇ and V₈ each represents a hydrogen atom, a halogen atom, an alkyl group, an acyl group, an acyloxy group, an alkoxycarbonyl group, a carbamoyl group, a sulfamoyl group, a carboxyl group, a cyano group, a hydroxyl group, an amino group, an acylamino group, an alkoxy group, an alkylthio group, an alkylsulfonyl group, a sulfonic acid group or an aryl group, provided that any two adjacent groups among V₁ to V₈ do not form a condensed ring by combining with each other, and when the Hammett's σ_p value of V_i (i = 1 to 8) is taken as σ_pi (i = 1 to 8), and Y is defined as Y = σ_p1 + σ_p2 + σ_p3 + σ_p4 + σ_p5 + σ_p6 + σ_p7 + σ_p8, Y ≦ -0.08 in the case of Z = oxygen atom, while Y ≦ -0.15 in the case of Z = sulfur atom; X represents a counter ion for charge balancing; and n represents the number of counter ions for rendering the charge of the compound neutral as a whole;
wherein L₁, L₂ and L₃ each represents an unsubstituted or substituted methine group; Q represents an aryl group containing at least one sulfo or carboxyl group; R₃ and R₄ each represents -COR₅, -COOR₅,
-CN, or -CF₃; R₅ and R₆ each represents a hydrogen atom, an unsubstituted or substituted alkyl group, or an unsubstituted or substituted aryl group; m represents 0, 1, 2, or 3; and n represents 0, 1, or 2; and M represents K or Na.
The alkyl group, alkyl moiety, carbamoyl group, sulfamoyl group, amino group, aryl group and aryl moiety represented by the substituent groups in the above-illustrated formulae are each intended to include further substituted ones.

DETAILED DESCRIPTION OF THE INVENTION

The sensitizing dyes represented by general formula (I) are described below in detail.
Z in general formula (I) represents an oxygen atom or a sulfur atom.
R₁ and R₂ each preferably represents an unsubstituted alkyl group containing not more than 18 carbon atoms (e.g., methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, decyl, dodecyl, octadecyl), and a substituted alkyl group (the alkyl moiety of which contains not more than 18 carbon atoms, and is substituted, e.g., by a carboxyl group, a sulfo group, a cyano group, a halogen atom (e.g., fluorine, chlorine, bromine), a hydroxyl group, an alkoxycarbonyl group containing not more than 8 carbon atoms (e.g., methoxycarbonyl, ethoxycarbonyl, phenoxycarbonyl, benzyloxycarbonyl), an alkoxy group containing not more than 8 carbon atoms (e.g., methoxy, ethoxy, benzyloxy, phenethyloxy), a monocyclic aryloxy group containing not more than 15 carbon atoms (e.g., phenoxy, p-tolyloxy), an acyloxy group containing not more than 8 carbon atoms (e.g., acetyloxy, propionyloxy), an acyl group containing not more than 8 carbon atoms (e.g., acetyl, propionyl, benzoyl), a carbamoyl group (e.g., carbamoyl, N,N-dimethylcarbamoyl, morpholinocarbonyl, piperidinocarbonyl), a sulfamoyl group (e.g., sulfamoyl, N,N-dimethylsulfamoyl, morpholinosulfonyl, piperidinosulfonyl), an aryl group containing not less than 15 carbon atoms (e.g., phenyl, 4-chlorophenyl, 4-methylphenyl, α-naphthyl), and so on).
More preferably, R₁ and R₂ each represents an unsubstituted alkyl group (e.g., methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl), or a sulfoalkyl group (e.g., 2-sulfoethyl, 3-sulfopropyl, 4-sulfobutyl).
In particular, it is desirable that either R₁ or R₂ should be butyl, pentyl, hexyl, heptyl or octyl, especially pentyl.
Substituent groups preferred as V₁, V₂, V₃, V₄, V₅, V₆, V₇ and V₈ each include a hydrogen atom, a halogen atom (e.g., fluorine, chlorine, bromine), an unsubstituted alkyl group containing not more than 10 carbon atoms (e.g., methyl, ethyl), a substituted, alkyl group containing not more than 18 carbon atoms (e.g., benzyl, α-naphthylmethyl, 2-phenylethyl, trifluoromethyl), an acyl group containing not more than 8 carbon atoms (e.g., acetyl, benzoyl), an acyloxy group containing not more than 8 carbon atoms (e.g., acetyloxy), an alkoxycarbonyl group containing not more than 8 carbon atoms (e.g., methoxycarbonyl, ethoxycarbonyl, benzyloxycarbonyl), a carbamoyl group (e.g., carbamoyl, N,N-dimethylcarbamoyl, morpholinocarbonyl, piperidinocarbonyl), a sulfamoyl group (e.g., sulfamoyl, N,N-dimethylsulfamoyl, morpholinosulfonyl, piperidinosulfonyl), a carboxyl group, a cyano group, a hydroxyl group, an amino group, an acylamino group containing not more than 8 carbon atoms (e.g., acetylamino), an alkoxy group containing not more than 10 carbon atoms (e.g., methoxy, ethoxy, benzyloxy), an alkylthio group containing not more than 10 carbon atoms (e.g., ethylthio), an alkylsulfonyl group containing not more than 5 carbon atoms (e.g., methylsulfonyl), a sulfonic acid group, and an aryl group containing not more than 15 carbon atoms (e.g., phenyl, tolyl).
Among these groups, a hydrogen atom, an unsubstituted alkyl group (e.g., methyl) and an alkoxy group (e.g., methoxy) are particularly preferred over others. However, all of V₁ to V₈ cannot be a hydrogen atom at the same time.
Among V₁ to V₈, any pair of substituent groups attached to adjacent carbon atoms cannot combine with each other to form a condensed ring and, what is more, when Hammett's σ_p value of V_i (i = 1 to 8) is taken as σ_pi (i = 1 to 8), and Y is defined as Y = σ_p1 + σ_p2 + σ_p3 + σ_p4 + σ_p5 + σ_p6 + σ_p7 + σ_p8, Y ≦ -0.08 in the case of Z = oxygen atom, while Y ≦ -0.15 in the case of Z = sulfur atom. More preferably Y ≦ -0.15 in case of Z = oxygen atom, and Y ≦ -0.30 in case of Z = sulfur atom. In particular, it is to be desired that the value of Y should be from -0.90 to -0.17 in case of Z = oxygen atom, while it should be from -1.05 to -0.34 in case of Z = sulfur atom.
The value σ_p used herein refers to the value described in Kagaku no Ryoiki (which means "Areas of Chemistry"), special number 122, pages 96-103, published by Nankodo, entitled "Yakubutsu no Kozo Kassei Sokan-Drug Design to Sayokisa Kenkyu no Shishin" (which means "Structural Activity Correlation of Medicines-Guide to Drug Design and Studies of Working Mechanisms"), compiled by Kozo Kassei Sokan Konwakai; and Corwin Hansch & Albert Leo, Substituent Constants for Correlation Analysis in Chemistry and Biology, pages 69-161, John Wiley & Sons.
The determination method of σ_p is described in Chemical Reviews, Vol. 17, pages 125-126 (1935).
According to the above-cited literature, σ_p of a hydrogen atom is 0, that of a methyl group is -0.17, and that of a methoxy group is -0.27.
X_n is included in the formula in order to indicate the presence or absence of cation(s) or anion(s) when it is required for rendering the total ionic charge of the dye neutral. Accordingly, n assumes a proper value not less than 0.
Typical cations include inorganic or organic ammonium ions and alkali metal ions. On the other hand, anions may be either inorganic or organic ones, with specific examples including halide ions (e.g., fluoride ion, chloride ion, bromide ion, iodide ion), substituted arylsulfonate ions (e.g., p-toluenesulfonate ion, p-chlorobenzenesulfonate ion), aryldisulfonate ions (e.g., 1,3-benzenedisulfonate ion, 1,5-naphthalenedisulfonate ion, 2,6-naphthalenedisulfonate ion), alkylsulfate ions (e.g., methylsulfate ion), sulfate ion, thiocyanate ion, perchlorate ion, tetrafluoroborate ion, picrate ion, acetate ion, and trifluoromethanesulfonate ion. Among these ions, iodide ion is preferred over others.
Specific examples of the sensitizing dye represented by general formula (I) of this invention are illustrated below. However, the invention should not be construed as being limited to these examples.
The compound to be used in this invention, which is represented by the foregoing general formula (I), can be synthesized on the basis of methods as described, e.g., in F.M. Hamer, Heterocyclic Compounds-Cyanine Dyes and Related Compounds, Chapter IX, pages 270 to 287, John Wiley & Sons, New York, London (1946); and D.M. Sturmer, Heterocyclic Compounds-Special Topics in Heterocyclic Chemistry, Chapter 8, paragraph 4, pages 482 to 515, John Wiley & Sons, New York, London (1977).
The compound of general formula (I) can be added to a silver halide emulsion in a manner well known in the art. In general, it is dissolved into a water-soluble solvent, e.g., methanol, ethanol, pyridine, methyl cellosolve, acetone, or a mixture of two or more of these solvents, and then added to a silver halide emulsion. Also, the compound can be dissolved into a mixture of water with a water-soluble organic solvent as cited above, and then added to a silver halide emulsion.
The addition may be carried out at any stage during the preparation of the silver halide emulsion, but is preferably performed during or after the chemical ripening of the emulsion, or before or after the addition of stabilizers or antifoggants to the emulsion.
The compound of general formula (I) does not have any particular limitation as to the addition amount, and can be added in an amount of from 1 × 10⁻⁶ to 1 × 10⁻³ mol per mol of silver halide, preferably from 1 × 10⁻⁵ to 3 × 10⁻⁴ mol per mol of silver halide.
The compounds of general formula (I) are spectral sensitizers to be principally used for red-sensitive silver halide emulsion layers, and for green- or blue-sensitive emulsion layers, and in addition thereto, generally known spectral sensitizers can be employed in this invention in combination with the compounds of general formula (I).
Examples of dyes suitable for green- and blue-sensitive layers include cyanine dyes, merocyanine dyes, complex cyanine dyes, complex merocyanine dyes, holopolar cyanine dyes, hemicyanine dyes, styryl dyes, and hemioxonol dyes. In particular, cyanine dyes, merocyanine dyes and complex merocyanine dyes are useful. Any nuclei usually present in cyanine dyes can be the basic heterocyclic nuclei of these dyes. More specifically, basic heterocyclic nuclei include pyrroline, oxazoline, thiazoline, pyrrole, oxazole, thiazole, selenazole, imidazole, tetrazole, pyridine and like nuclei; nuclei formed by fusing together one of the above-described nuclei and an alicyclic hydrocarbon ring; and nuclei formed by fusing together one of the above-described nuclei and an aromatic hydrocarbon ring, with specific examples including indolenine, benzindolenine, indole, benzoxazole, naphthoxazole, benzothiazole, naphthothiazole, benzoselenazole, benzimidazole, quinoline and like nuclei. Each of these nuclei may be substituted on a carbon atom(s).
The merocyanine and complex merocyanine dyes can contain 5- or 6-membered heterocyclic nuclei, such as pyrazoline-5-one, thiohydantoin, 2-thioxazolidine-2,4-dione, thiazoline-2, 4-dione, rhodanine, thiobarbituric acid and like nuclei, as ketomethylene structure-containing nuclei.
These sensitizing dyes may be employed individually or in combination. Combinations of sensitizing dyes are often employed for the purpose of supersensitization. Typical examples of supersensitizing combinations are disclosed in U.S. Patents 2,688,545, 2,977,229, 3,397,060, 3,522,052, 3,527,641, 3,617,293, 3,628,964, 3,666,480, 3,672,898, 3,679,428, 3,703,377, 3,769,301, 3,814,609, 3,837,862 and 4,026,707, British Patents 1,344,281 and 1,507,803, JP-B-43-4936, JP-B-53-12375, JP-A-52-110618 and JP-A-52-109925.
Next, general formula (II) is described in detail.
The substituents R₅ and R₆ in formula (II) include a hydrogen atom, an unsubstituted alkyl group (e.g., methyl, ethyl, t-butyl, octyl, cyclohexyl, benzyl and so on, preferably those containing 1 to 13 carbon atoms), a substituted alkyl group (such as those containing as substituent group(s) a sulfo group (e.g., sulfomethyl, sulfoethyl), a carboxyl group (e.g., carboxymethyl, carboxyethyl), a hydroxyl group(s) (e.g., hydroxyethyl, 1,2-dihydroxypropyl), an alkoxy group (e.g., methoxyethyl, ethoxyethyl), a halogen atom(s) such as a fluorine, chlorine or bromine atom (e.g., 2-chloroethyl, 2-bromoethyl, 2,2,2-trifluoroethyl), a cyano group (e.g., cyanoethyl), a sulfonyl group (e.g., methanesulfonylethyl), a nitro group (e.g., 2-nitrobutyl, 2-nitro-2-methylpropyl), an amino group (e.g., dimethylaminoethyl, diethylaminopropyl), or an aryl group (e.g., benzyl, p-chlorobenzyl)), unsubstituted aryl groups (e.g., phenyl, naphthyl and so on, preferably those containing 6 to 18 carbon atoms), and a substituted aryl group (such as those containing 6 to 15 carbon atoms and, as substituent group(s), a halogen atom(s) (e.g., fluorine, chlorine, bromine), an alkyl group(s) (e.g., methyl, ethyl, t-butyl, etc., preferably those containing 1 to 4 carbon atoms), an alkoxy group(s) (e.g., methoxy, ethoxy, etc., preferably those containing 1 to 4 carbon atoms), a sulfo group(s) (e.g., o-sulfo), a carboxyl group(s) (e.g., o-carboxy), a cyano group(s) (e.g., p-cyano), an amino group(s) (e.g., p-dimethylamino, p-acetylamino), or a hydroxy group(s) (e.g., p-hydroxy)).
The substituent Q represents an aryl group containing a sulfo and/or carboxyl group(s) (e.g., o-sulfophenyl, o,p-disulfophenyl, p-carboxyphenyl, m-carboxyphenyl, 4-sulfonaphthyl), or an aryl group substituted by not only sulfo and/or carboxyl group(s) but also another substituent (such as those containing as another substituent a halogen atom (e.g., p-chloro-o-sulfophenyl, p-bromo-o-sulfophenyl, o-chloro-p-carboxyphenyl), an alkyl group (e.g., those containing 1 to 3 carbon atoms, such as o-methyl-p-sulfophenyl), or an alkoxy group (e.g., those containing 1 to 3 carbon atoms, such as o-methoxy-p-carboxyphenyl)). Among these groups, a phenyl group containing at least two sulfo groups is particularly preferred over others. The sulfo and the carboxyl groups may assume not only the form of free acid, but also the form of salt (e.g., sodium salt, potassium salt, ammonium salt, quaternary ammonium salt).
The linkage group L₁, L₂ and L₃ include unsubstituted and substituted methine groups (a substituent group of which is methyl, ethyl, phenyl, benzyl, 1-sulfoethyl, and so on).
n represents 0, 1 or 2, and m represents 0, 1, 2 or 3.
It is preferred that when n is 2, L₁, L₂ and L₃ each represents a methine group.
Specific examples of the dyes to be used in this invention are illustrated below. However, the invention should not be construed as being limited to these examples.
Among the dyes represented by general formula (II) of this invention, those having a pentamethine link (a link consisting of unsubstituted and/or substituted methine groups the number of which amounts to 5 in all) are used at a coverage of preferably 1 × 10⁻⁵ mol/m² or above, more preferably from 1.2 × 10⁻⁵ to 5 × 10⁻⁴ mol/m², and most preferably from 1.4 × 10⁻⁵ to 2 × 10⁻⁴ mol/m². When two or more kinds of the dyes of general formula (II) each having a pentamethine link are used, the total coverage of them are within the range described above.
If the dyes of the above-described type are used at a coverage of 1 × 10⁻⁵ mol/m² or less, the sharpness improving effect produced thereby is insufficient, whereas if the coverage is increased beyond 5 × 10⁻⁴ mol/m², there are caused undesirable phenomena that the sensitivity is lowered, and decoloration and elution rates of the dyes during photographic processing are lowered to cause color stains after the processing. Other dyes may be used at any coverages so far as the balance of sharpness among blue-, green- and red-sensitive silver halide emulsion layes is acquired. The addition of these dyes to silver halide emulsions may be carried out at any time provided that it is done before coating of the emulsions.
When a monomethine oxonol dye or a trimethine oxonol dye (in general formula (II), n = 0) is used, the coverage of these dyes are preferably controlled to from 1 × 10⁻⁶ to 1 × 10⁻³ mol/m².
The dyes of general formula (II) of this invention can be dispersed into light-sensitive or light-insensitive layers in various known manner. Specifically, they may be dispersed directly into light-sensitive or light-insensitive layers, or added thereto in the form of a solution in a proper solvent, such as methyl alcohol, ethyl alcohol, propyl alcohol, methyl cellosolve, halogenated alcohols disclosed in JP-A-48-9715 and U.S. Patent 3,756,830, acetone, water, pyridine, or a mixture of two or more of these solvents.
In order to further enhance the effects of this invention, it is to be desired that water-soluble bromides should be incorporated in silver halide emulsion layers.
Examples of usable water-soluble bromides include potassium bromide, sodium bromide, ammonium bromide and so on. It is desirable that these bromides should be added to silver halide emulsions during the chemical ripening and/or upon the preparation of coating compositions for completing a photographic material. A preferred amount to be added is from 1 × 10⁻³ to 1 × 10⁻¹ mol per mol of silver halide.
In this invention, it is effective to use supersensitizers to further improve the freshness keeping property, as well as to adjust the wavelengths at which silver halides are sensitive to light.
As for the supersensitizers, there are descriptions in Photographic Science and Engineering, Vol. 13, pp. 13-17 (1969); ibid., Vol. 18, pp. 418-430 (1974); T.H. James, The Theory of the Photographic Process, 4th Ed., p. 259, Macmillan Publishers (1977); and so on. As well known, higher sensitivities can be achieved by choosing proper combinations of sensitizing dyes with supersensitizers.
Although it is possible to use any kind of supersensitizer, compounds represented by the following general formula (III) are particularly preferred in this invention:
wherein D represents a divalent aromatic group; R₇, R₈, R₉ and R₁₀ each represents a hydrogen atom, a hydroxy group, an alkoxy group, an aryloxy group, a halogen atom, a heterocyclic group, a mercapto group, an alkylthio group, an arylthio group, a heterocyclic thio group, an amino group, an alkylamino group, a cyclohexylamino group, an arylamino group, a heterocyclic amino group, an aralkylamino group, or an aryl group; Y₁ and Z₃ each represents -N= or -CH=, provided that at least either of them is -N=; and Y₂ and Z₄ have the same meaning as Y₁ and Z₃, respectively.
More specifically, D represents a divalent aromatic group (e.g., a residue of a single aromatic nucleus, a residue of a condensed aromatic nucleus in which at least two aromatic nuclei are fused together, a link formed by bonding at least two aromatic nuclei directly or via atom(s) or group(s)), with specific examples including biphenyl, naphthylene, stilbene, those having a dibenzyl skeleton, and so on. In particular, those shown below as D₁ and D₂ are preferred.
wherein M represents a hydrogen atom, or a cation capable of imparting solubility in water to the compound (e.g., alkali metal ions (Na⁺, K⁺), ammonium ion).
In the case of D = D₂, at least one from among R₇, R₈, R₉ and R₁₀ has a substituent group containing at least one SO₃M group, where M has the same meaning as above.
R₃, R₄, R₅ and R₆ each represents a hydrogen atom, a hydroxyl group, an alkoxy group (e.g., methoxy, ethoxy), an aryloxy group (e.g., phenoxy, naphthoxy, o-tolyloxy, p-sulfophenoxy), a halogen atom (e.g., chlorine, bromine), a heterocyclic group (e.g., morpholinyl, piperidyl), a mercapto group, an alkylthio group (e.g., methylthio, ethylthio), an arylthio group (e.g., phenylthio, tolylthio), a heterocyclic thio group (e.g., benzothiazolylthio, benzimidazolylthio, phenyltetrazolylthio), an amino group, an alkylamino group (e.g., methylamino, ethylamino, propylamino, dimethylamino, diethylamino, dodecylamino, β-hydroxyethylamino, di-β-hydroxyethylamino, β-sulfoethylamino), a cyclohexylamino group, an arylamino group (e.g., anilino, o-, m- or p-sulfoanilino, o-, m- or p-chloroanilino, o-, m- or p-anisidino, o-, m- or p-toluidino, o-, m- or p-carboxyanilino, hydroxyanilino, sulfonaphthylamino, o-, m- or p-aminoanilino, o-acetaminoanilino), a heterocyclic amino group (e.g., 2-benzothiazolylamino, 2-pyridylamino), an aralkylamino group (e.g., benzylamino) or an aryl group (e.g., phenyl).
Among the compounds represented by general formula (III), those containing an aryloxy group, a heterocyclic thio group or a heterocyclic amino group as at least one substituent among R₇, R₈, R₉ and R₁₀ are particularly preferred.
Typical representatives of the compounds represented by general formula (III) are given below. However, the invention should not be construed as being limited to these compounds.

(III- 1): Disodium 4,4′-bis[2,6-di(benzothiazolyl-2-thio)pyrimidine-4-ylamino]stilbene-2,2′-disulfonate
(III- 2): Disodium 4,4′-bis[2,6-di(benzothiazolyl-2-amino)pyrimidine-4-ylamino]stilbene-2,2′-disulfonate
(III- 3): Disodium 4,4′-bis[2,6-di(1-phenyltetrazolyl-5-thio)pyrimidine-4-ylamino]stilbene-2,2′-disulfonate
(III- 4): Disodium 4,4′-bis[2,6-di(benzoimidazolyl-2-thio)pyrimidine-4-ylamino]stilbene-2,2′-disulfonate
(III- 5): Disodium 4,4′-bis[2-chloro-6-(2-naphthyloxy)pyrimidine-4-ylamino]biphenyl-2,2′-disulfonate
(III- 6): Disodium 4,4′-bis[2,6-di(naphthyl-2-oxy)pyrimidine-4-ylamino]stilbene-2,2′-disulfonate
(III- 7): Disodium 4,4′-bis[2,6-di(naphthyl-2-oxy)pyrimidine-4-ylamino]bibenzyl-2,2′-disulfonate
(III- 8): Disodium 4,4′-bis(2,6-diphenoxypyrimidine-4-ylamino)stilbene-2,2′-disulfonate
(III- 9): Disodium 4,4′-bis(2,6-diphenylthiopyrimidine-4-ylamino)stilbene-2,2′-disulfonate
(III-10): Disodium 4,4′-bis(2,6-dichloropyrimidine-4-ylamino)stilbene-2,2′-disulfonate
(III-11): Disodium 4,4′-bis(2,6-dianilinopyrimidine-4-ylamino)stilbene-2,2′-disulfonate
(III-12): Disodium 4,4′-bis[4,6-di(naphthyl-2-oxy)triazine-4-ylamino]stilbene-2,2′-disulfonate
(III-13): Disodium 4,4′-bis(4,6-dianilinotriazine-4-ylamino)stilbene-2,2′-disulfonate
(III-14): Disodium 4,4′-bis(2,6-dimercaptopyrimidine-4-ylamino)biphenyl-2,2′-disulfonate
(III-15): Disodium 4,4′-bis[4,6-di(naphthyl-2-oxy)pyrimidine-2-ylamino]stilbene-2,2′-disulfonate
(III-16): Disodium 4,4′-bis[4,6-di(benzothiazolyl-2-thio)pyrimidine-2-ylamino]stilbene-2,2′-disulfonate
(III-17): Disodium 4,4′-bis[4,6-di(1-phenyltetrazolyl-2-amino)pyrimidine-2-ylamino]stilbene-2,2′-disulfonate
(III-18): Disodium 4,4′-bis[4,6-di(naphthyl-2-oxy)pyrimidine-2-ylamino]bibenzyl-2,2′-disulfonate

As for the addition order of the foregoing compounds represented by general formulae (I) and (III), either of them may be added first, or they may be added at the same time. Also, they can be added in the form of a mixed solution.
The amount of compound represented by general formula (III) added is from 1 × 10⁻⁶ to 1 × 10⁻¹ mol, preferably from 5 × 10⁻⁵ to 1 × 10⁻² mol, per mol of silver halide. A preferred molar ratio of the amount of compound represented by general formula (I) added to that of compound represented by general formula (III) added can be chosen from 1/50 to 10/1.
Silver halides which can be used in this invention are preferably silver chlorobromide and silver chloroiodobromide. Also, mixtures of silver chloride, silver bromide and so on may be employed. When the silver halide emulsions are used for color photographic paper, it is desirable that the emulsion grains should contain silver chloride in a certain fraction, specifically should be silver chlorobromide or silver chloroiodobromide having a chloride content of at least 1 mol%, preferably 10 mol% or more, because particularly high developing speed and excellent processability are required of color photographic paper. In the case where silver chloroiodobromide is used as the silver halide employed in this invention, a preferred iodide content is not more than 2 mol%.
In the case where the photographic material is to be subjected to rapid processing, halide compositions of silver halide grains to be used in this invention preferably contain chloride in a proportion of 90 mol% or more of the entire halides constituting the grains, and not containing iodide in a substantial sense. The expression "not containing iodide in a substantial sense" signifies an iodide content of 1.0 mol% or less. More preferable halide compositions of silver halide grains are chlorobromides or chlorides containing chloride in a proportion of 95 mol% or more of the entire halides constituting the grains, and not containing iodide in a substantial amount. The optimal halide compositions are chlorobromides or chlorides containing chloride in a proportion of 97 mol% or more of the entire halides constituting the grains, and not containing iodide in a substantial amount.
More specifically, desirable silver halide grains in this invention are those having a silver bromide-localized phase wherein silver bromide content is at least 20 mol%. Such a silver bromide-localized phase may be located at any part of the grain, if desired. That is, it may be located at the interior of the grain, or the surface or sub-surface portion of the grain. Further, the localized phase may be present separately at the interior and the surface or the sub-surface parts. Moreover, the localized phase may be present at the interior or the surface in a stratiform so as to encircle the silver halide grain, or in a discrete isolated form. As one example of preferred forms of the silver bromide-localized phase, mention may be made of such a form that the localized phase having a bromide content of at least 20 mol% attains a local epitaxial growth at the grain surface.
Although a preferred content of silver bromide in the localized phase is more than 20 mol%, too high a content thereof tend to give undesirable characteristics to photographic materials. For example, desensitization is apt to be caused by the pressure applied to the photographic materials, and great changes in sensitivity and gradation occur due to fluctuation in compositions of processing solutions. Taking into account these points, the content of silver bromide in the localized phase ranges preferably from 20 to 60 mol%, particularly from 30 to 50 mol%. The content of silver bromide in the localized phase can be determined by X-ray diffractometry as described, e.g., in Shin Jikken Kagaku Koza 6, Kozo Kaiseki (which means "New Lectures on Experimental Chemistry VI, Structural Analyses"), compiled by Nihon Kagakukai (Japanese Chemical Society), published by Maruzen, by the X-ray Photoelectron Spectroscopy (XPS) method as described, e.g., in Hyomen Bunseki-IMA, Auger Denshi Kodenshi Bunko no Oyo- (which means "Surface Analyses-Applications of IMA, Auger Electron Photoelectron Spectroscopy"), published by Kodansha, and so on.
It is desirable that the proportion of silver present in the localized phase should be from 0.1 to 20%, preferably from 0.5 to 7%, of the entire silver constituting the individual silver halide grains of this invention.
At the interface between the above-described silver bromide-localized phase and another phase, there may be a definitive phase boundary, or a short transition range wherein the halogen composition varies by slow degrees.
Various kinds of processes can be employed for forming such a localized phase as to have a high bromide content. For instance, the localized phase can be formed by reacting soluble silver salts with soluble halides in accordance with a single jet process or a double jet process. In addition, it can be formed using a so-called conversion process which includes the step of converting the already formed silver halide into one which has a smaller solubility product. Moreover, it can be formed through the addition of fine grains of silver bromide and the recrystallization thereof at the grain surface of silver chloride.
As for the silver halide grains which can be used in this invention, those having any face at the exterior surface, for example, those having a (100) face, those having a (111) face, those having both (100) and (111) faces, and those comprising higher order faces, can be used to advantage. In particular, grains formed mainly by (100) faces are preferred over others.
Silver halide grains to be used in this invention may have an irregular crystal form, such as that of a sphere.
In addition, a silver halide emulsion to be used in this invention may be such an emulsion as to contain tabular grains having an average aspect ratio (diameter/thickness ratio) of 5 or more, particularly 8 or more, in a fraction of 50% or more, based on the projected area of all of the grains.
The average size of the silver halide grains which can be used in this invention may be within the conventional range, and preferably is from 0.1 to 1.5 µm. The grain size distribution may be polydispersed or monodispersed, but is preferably monodispersed. The degree of monodispersion in the grain size distribution is preferably 0.20 or less, more preferably 0.15 or less, expressed in terms of the ratio of the statistical standard deviation (s) to the average grain size (d), that is, s/d. Also, two or more kinds of monodispersed emulsions as described above may be used as a mixture.
In the process of producing silver halide grains or allowing the produced silver halide grains to ripen physically, cadmium salts, zinc salts, lead salts, thallium salts, iridium salts or complexes thereof, rhodium salts or complexes thereof, iron salts or complexes thereof, and/or the like may be present.
After the formation of the silver halide grains, the emulsion is generally subjected to physical ripening, desalting and chemical ripening prior to coating.
In the precipitation, physical ripening and chemical ripening steps, known silver halide solvents (e.g., ammonia, potassium thiocyanate, thioethers and thione compounds disclosed in U.S. Patent 3,271,157, JP-A-51-12360, JP-A-53-82408, JP-A-53-144319, JP-A-54-100717, JP-A-54-155828, and so on) can be used. The removal of soluble salts from the physically ripened emulsion can be effected using the noodle washing method, the flocculation sedimenting method, or the ultrafiltration method.
The silver halide emulsions to be used in this invention can be chemically sensitized using a sulfur or selenium sensitization process, a reduction sensitization process, a noble metal sensitization process and so on independently or in combination.
More specifically, sulfur sensitization using an active gelatin capable of reacting with silver ion and compounds containing sulfur (e.g., thiosulfates, thioureas, mercapto compounds, rhodanines); reduction sensitization using reducing materials (e.g., stannous salts, amines, hydrazine derivatives, formamidinesulfinic acid, silane compounds); sensitization with noble metal compounds (e.g., gold complexes, and complex salts of Group VIII metals, such as Pt, Ir, Pd, Rh, Fe, etc.); and so on can be employed individually or as a combination thereof. In using these sensitization processes, stabilizers, such as nucleic acids or degradation products thereof, compounds containing a purine nucleus or a pyrimidine nucleus, or hydroxytetraazaindene may be present.
In order to satisfy the gradation desired by the color photographic material of this invention, two or more of monodispersed silver halide emulsions (preferably having their respective variation coefficients in the above-described range) which have in a substantial sense the same color sensitivity, but different grain sizes can be coated as a mixture in one and the same layer, or layered over one another in separate layers. Also, two or more of polydisperse silver halide emulsions, or a combination of monodisperse emulsion(s) and polydisperse emulsion(s) can be coated as a mixture in a single layer, or separately in a multiple layer.
Couplers to be used in this invention are described below.
The incorporation of various kinds of color couplers is required of the photographic material of this invention. The term color couplers used herein refers to compounds capable of forming dyes by the coupling reaction with the oxidation products of aromatic primary amine developers. Typical examples of useful color couplers include naphthol or phenol compounds, pyrazolone or pyrazoloazole compounds, and open chain or heterocyclic ketomethylene compounds. Specific examples of these compounds usable as cyan, magenta and yellow couplers, respectively, in this invention are disclosed in the patent cited in Research Disclosure (RD), No. 17643, Item VII-D (December, 1978) and No. 18717 (November, 1979).
Color couplers to be used in this invention are preferably rendered nondiffusible by introducing a ballast group thereinto, or by assuming a polymerized form. From the standpoint of saving silver, 2-equivalent color couplers which have a splitting-off group at the coupling active site are preferred to 4-equivalent ones which have a hydrogen atom at that site. In addition. couplers which can produce dyes with moderate diffusibility, colorless couplers, or DIR couplers which can release a development inhibitor as the coupling reaction proceeds, or couplers capable of releasing a development accelerator as the coupling reaction proceeds can be employed.
As for the yellow couplers usable in this invention, oil-protected acylacetamide type couplers can be given as representative examples. Specific examples of such couplers are disclosed, e.g., in U.S. Patents 250,710, 2,875,057 and 3,265,506. In this inventio, 2-equivalent yellow couplers are preferred, and representatives thereof are those of the type which have a splitting-off group attached to the coupling active site via its oxygen, as disclosed in U.S. Patents 3,408,194, 3,447,928, 3,933,501 and 4,022,620, and so on; and those of the type which have a splitting-off group attached to the coupling active site vai its nitrogen, as disclosed in JP-B-58-10739, U.S. Patents 4,401,752 and 4,326,024, RD, 18053 (April, 1979), British Patent 1,425,020, West German Patent Applications (OLS) 2,219,917, 2,261,361, 2,329,587 and 2,433,812, JP-A-62-240965, and so on. Yellow couplers of α-pivaloylacetanilide type are excellent in fastness of the dyes produced, especially light fastness thereof. On the other hand, those of α-benzoylacetanilide type can provide high density of developed color.
Magenta couplers usable in this invention include those of oil-protected indazolone or cyanoacetyl types, more preferably those of 5-pyrazolone type, and those of pyrazoloazole types such as pyrazolotriazoles. As for the 5-pyrazolone type couplers, those having an arylamino group or an acylamino group at the 3-position are advantageous from the standpoints of hue and density of the developed colors, and representative examples thereof are disclosed, e.g., in U.S. Patents 2,311,082, 2,343,703, 2,600,788, 2,908,573, 3,062,653, 3,152,896 and 3,936,015. Suitable examples of splitting-off groups of 2-equivalent 5-pyrazolone type couplers include those having a nitrogen atom at the splitting-off site, as disclosed in U.S. Patent 4,310,619; and the arylthio groups disclosed in U.S. Patent 4,351,897 and WO (PCT) 88/04795. Also, high density of developed color is obtained by the ballast group-containing 5-pyrazolone type couplers disclosed in European Patent 73,636.
Suitable examples of pyrazoloazole type couplers include the pyrazolobenzimidazoles disclosed in U.S. Patent 3,369,879, and preferably the pyrazolo[5,1-c]1,2,4-triazoles disclosed in U.S. Patent 3,725,067, the pyrazolotetrazoles described in Research Disclosure, 24220 (June, 1984) and the pyrazolopyrazoles described in Research Disclosure, 24230 (June, 1984).
Of pyrazoloazole type couplers, those which are favorable in respects that side absorption in the yellow region is small and fastness to light is high are the imidazo[1,2-b]pyrazoles disclosed in European Patent 119,741, and those which are particularly preferred over others in the foregoing respects are the pyrazolo[1,5-b]1,2,4-triazoles disclosed in European Patent 119,860.
Cyan couplers usable in this invention include those of oil-protected naphthol or phenol type, and representatives thereof are the naphthol type couplers disclosed in U.S. Patent 2,474,293, preferably the 2-equivalent naphthol couplers of the type which have a splitting-off group attached to the coupling active site via its oxygen, as disclosed in U.S. Patents 4,052,212, 4,146,396, 4,228,233 and 4,296,200. On the other hand, specific examples of phenol type couplers are disclosed in U.S. Patents 2,369,929, 2,801,171, 2,772,162 and 2,895,826, and so on. This invention prefers cyan couplers fast to moisture and heat, and typical examples of such couplers include the phenol type cyan couplers disclosed in U.S. Patent 3,772,002, which have an alkyl group containing not less than 2 carbon atoms at the meta-position of the phenol nucleus; cyan couplers of 2,5-diacylaminophenol type as disclosed, e.g., in U.S. Patents 2,772,162, 3,758,308, 4,126,396, 4,334,011 and 4,327,173, West German Patent Application (OLS) 3,329,729, and U.S. Patent 4,500,635; and couplers of the type which have a phenylureido group and an acylamino group at the 2- and 5-position of the phenol nucleus, respectively, as disclosed, e.g., in U.S. Patents 3,446,622, 4,333,999, 4,451,559 and 4,427,767.
Cyan, magenta and yellow couplers which can be preferably used in this invention are represented by the following general formulae (VI), (VII), (VIII), (IX) and (X):
In the foregoing formulae (VI) and (VII), R₁, R₂ and R₄ each represents a substituted or unsubstituted aliphatic, aromatic or heterocyclic group; R₃, R₅ and R₆ each represents a hydrogen atom, a halogen atom, an aliphatic group, an aromatic group or an acylamino group, and further R₃ may be nonmetal atoms to form a nitrogen-containing 5- or 6-membered ring by combining with R₂; Y₁ and Y₂ each represents a hydrogen atom or a group capable of splitting off upon coupling reaction with the oxidation product of a developing agent (which is abbreviated as a splitting-off group). A splitting-off group represented by Y₁ or Y₂ include those comprising an aliphatic group, an aromatic group, a heterocyclic group, an aliphatic, aromatic or heterocyclic sulfonyl group, or an aliphatic, aromatic or heterocyclic carbonyl group, which is attached to the coupling active carbon via its oxygen, nitrogen, sulfur or carbon atom; a halogen atom; and an aromatic azo group. Aliphatic, aromatic and heterocyclic moieties contained in the above-cited splitting-off groups may be substituted by groups allowed as substituent groups for R₁. When two or more of substituent groups are present, they may be the same or not, and may further be substituted by groups allowed as substituent groups for R₁.
In the cyan couplers of general formulae (VI) and (VII), an aliphatic group represented by R₁, R₂ or R₄ includes those containing 1 to 32 carbon atoms, such as a methyl group, a butyl group, a tridecyl group, a cyclo hexyl group, an allyl group, etc., an aromatic group includes a phenyl group, a naphthyl group, etc., and a heterocyclic group includes a 2-pyridyl group, a 2-imidazolyl group, a 2-furyl group, a 6-quinolyl group, etc. These groups each may further be substituted by an alkyl group, an aryl group, a heterocyclic group, an alkoxy group (e.g., methoxy, 2-methoxyethoxy), an aryloxy group (e.g., 2,4-di-tert-amylphenoxy, 2-chlorophenoxy, 4-cyanophenoxy), an alkenyloxy group (e.g., 2-propenyloxy), an acyl group (e.g., acetyl, benzoyl), an ester group (e.g., butoxycarbonyl, phenoxycarbonyl, acetoxy, benzoyloxy, butoxysulfonyl, toluenesulfonyloxy), an amido group (e.g., acetylamino, methanesulfonamido, dipropylsulfamoylamino), a carbamoyl group (e.g., dimethylcarbamoyl, ethylcarbamoyl), a sulfamoyl group (e.g., butylsulfamoyl), an imido group (e.g., succinimido, hydantoinyl), a ureido group (e.g., phenylureido, dimethylureido), an aliphatic or aromatic sulfonyl group (e.g., methanesulfonyl, phenylsulfonyl), an aliphatic or aromatic thio group (e.g., ethylthio, phenylthio), a hydroxyl group, a cyano grop, a carboxyl group, a nitro group, a sulfo group, a halogen atom, or/and so on.
When R₃ and R₅ in general formula (VI) each represents a group capable of having a substituent group, it may be substituted by group(s) allowed as substituent(s) for R₁.
As for the substituent R₅ in general formula (VII), it preferably is an aliphatic group, such as a methyl group, an ethyl group, a propyl group, a butyl group, a pentadecyl group, a tert-butyl group, a cyclohexyl group, a cyclohexylmethyl group, a phenylthiomethyl group, a dodecyloxyphenylthiomethyl group, a butanamidomethyl group, a methoxymethyl group, or the like.
As specific examples of splitting-off groups (including splitting-off atoms) represented by Y₁ and Y₂ in general formulae (VI) and (VII), respectively, mention may be made of a halogen atom (e.g., fluorine, chlorine, bromine), an alkoxy group (e.g., ethoxy, dodecyloxy, methoxyethylcarbamoylmethoxy, carboxypropyloxy, methylsulfonylethoxy), an aryloxy group (e.g., 4-chlorophenoxy, 4-methoxyphenoxy, 4-carboxyphenoxy), an acyloxy group (e.g., acetoxy, tetradecanoyloxy, benzoyloxy), a sulfonyloxy group (e.g., methanesulfonyloxy, toluenesulfonyloxy), an amido group (e.g., dichloroacetylamino, heptafluorobutyrylamino, methanesulfonylamino, toluenesulfonylamino), an alkoxycarbonyloxy group (e.g., ethoxycarbonyloxy, benzyloxycarbonyloxy), an aryloxycarbonyloxy group (e.g., phenoxycarbonyloxy), an aliphatic or aromatic thio group (e.g., ethylthio, phenylthio, tetrazolylthio), an imido group (e.g., succinimido, hydantoinyl), an aromatic azo group (e.g., phenylazo), and so on. These splitting-off groups may contain a photographically useful group.
Among the cyan couplers represented by general formulae (VI) and (VII), preferred ones are as follows.
In general formula (VI), R₁ is an aryl group or a heterocyclic group, more preferably an aryl group substituted by a halogen atom, an alkyl group, an alkoxy group, an aryloxy group, an acylamino group, an acyl group, a carbamoyl group, a sulfonamido group, a sulfamoyl group, a sulfonyl group, a sulfamido group, an oxycarbonyl group or a cyano group.
When R₂ does not form a ring by combining with R₃ in general formula (VI), R₂ is preferably a substituted or unsubstituted alkyl or aryl group, particularly preferably an alkyl group substituted by a substituted aryloxy group, and R₃ is a hydrogen atom.
In general formula (VII), R₄ is preferably a substituted or unsubstituted alkyl or aryl group, particularly preferably an alkyl group substituted by a substituted aryloxy group.
R₅ in general formula (VII) preferably is an alkyl group containing 2 to 15 carbon atoms, or a methyl group substituted by a group containing at least one carbon atom, preferably an arylthio group, an alkylthio group, an acylamino group, an aryloxy group or an alkyloxy group.
In general formula (VII), R₅ is more preferably an alkyl group containing 2 to 15 carbon atoms, and particularly preferably an alkyl group containing 2 to 4 carbon atoms.
Preferred R₆ in general formula (VII) is a hydrogen atom or a halogen atom, preferably a chlorine atom or a fluorine atom.
Y₁ and Y₂ preferred in general formulae (VI) and (VII), respectively, are a hydrogen atom, a halogen atom, an alkoxy group, an aryloxy group, an acyloxy group or a sulfonamido group.
In general formula (VII), Y₂ is preferably a halogen atom, particularly a chlorine atom or a fluorine atom. When n = 0 in general formula (VI), Y₁ is preferably a halogen atom, and particularly preferably a chlorine atom or a fluorine atom.
In general formula (VIII), R₇ and R₉ each represents an aryl group, R₈ represents a hydrogen atom, an aliphatic or aromatic acyl group, or an aliphatic or aromatic sulfonyl group, and Y₃ represents a hydrogen atom or a splitting-off group. Substituent groups allowed for an aryl group (preferably a phenyl group) represented by R₇ and R₉ include the same ones allowed for the substituent R₁. When two or more substituent groups are present, they may be the same or not. R₈ is preferably a hydrogen atom, or an aliphatic acyl or sulfonyl group, particularly preferably a hydrogen atom. A preferred Y₃ is a splitting-off group of the type which splits off at the site of sulfur, oxygen or nitrogen atom, particularly preferably at the site of sulfur atom.
In general formula (IX), R₁₀ represents a hydrogen atom or a substituent group, and Y₄ represents a hydrogen atom or a splitting-off group. Examples of the splitting-off group represented by Y₄ include the same examples as those represented by Y₁ and Y₂. Za, Zb and Zc each represents an unsubstituted or substituted methine group, =N- or -NH-, and either the Za-Zb bond or the Zb-Zc bond is a double bond, and the remainder is a single bond. When the Zb-Zc bond is a carbon-carbon double bond, it may constitute a part of the aromatic ring. The couplers of general formula (IX) may form a polymer (including a dimer) via R₁₀, or Y₄. In the case where Za, Zb or Zc is a substituted methine, the couplers may form a polymer (including a dimer) via the substituted methine.
Among the couplers represented by general formula (IX), those represented by the following general formulae (IXa), (IXb), (IXc), (IXd) and (IXe) are preferred over others.
In the foregoing formulae (IXa) to (IXe), R₁₆, R₁₇ and R₁₈ each represents an aliphatic group, an aromatic group or a heterocyclic group, which may be substituted by any of groups allowed as a substituent for R₁. R₁₆, R₁₇ and R₁₈ each may further be
RO-, R
-, R
O-,

RS-, RSO₂-, RSO₂NH-,
R
NH-, RNH-, RO
NH-,

a hydrogen atom, a halogen atom, a cyano group or an imido group. Therein, R represents an alkyl group, an aryl group or a heterocyclic group. Furthermore, R₁₆, R₁₇ and R₁₈ each may be a carbamoyl group, a sulfamoyl group, a ureido group or a sulfamoyl group, the nitrogen atom of which may be substituted by any of groups allowed as a substituent for R₁. Also, any of the substituents R₁₆, R₁₇, R₁₈ and Y₄ may become a divalent group via which the coupler can form a dimer, or a divalent linking group to connect the main chain of a polymer and the coupler chromophore. Y₄ represents the same meaning as that in general formula (IX).
Groups preferred as R₁₆, R₁₇ and R₁₈ include a hydrogen atom, a halogen atom, an aliphatic group, an aromatic group, a heterocyclic group, RO-, RCONH-, RSO₂NH-, RNH-, RS- and ROCONH-, and those preferred as Y₄ include a halogen atom, an acylamino group, an imido group, an aliphatic or aromatic sulfonamido group, a 5- or 6-membered nitrogen-containing heterocyclic group which is attached to the coupling active site via their respective nitrogen atoms, an aryloxy group, an alkoxy group, an arylthio group and an alkylthio group.
In general formula (X), R₁₁ represents a halogen atom or an alkoxy group, and R₁₂ represents a hydrogen atom, a halogen atom or an alkoxy group. A represents -NHCOR₁₃, -NHSO₂-R₁₃,
-COOR₁₃ or -SO₂N-R₁₃, wherein R₁₃ and R₁₄ each represents an alkyl group. Y₅ represents a splitting-off group. The alkoxy group represented by R₁₂, and the alkyl groups represented by R₁₃ and R₁₄ may be substituted by any of substituents allowed for R₁. Splitting-off groups preferred as Y₅ are those represented by the following general formulae (Xa) to (Xg):
-OR₂₀ (Xa)
wherein R₂₀ represents an optionally substituted aryl or heterocyclic group;
wherein R₂₁ and R₂₂ may be the same or different, each being a hydrogen atom, a halogen atom, a carboxylate group, an amino group, an alkyl group, an alkylthio group, an alkoxy group, an alkylsulfonyl group, an alkylsulfinyl group, a carboxyl group, a sulfo group, or an unsubstituted or substituted phenyl or heterocyclic group;
wherein W₁ represents nonmetal atoms necessary to form a 4-, 5- or 6-membered ring.
Among the groups represented by formula (Xd), those of the following formulae (Xe) to (Xg) are preferred over others.
In the foregoing formulae, R₂₃ and R₂₄ each represents a hydrogen atom, an alkyl group, an aryl group, an alkoxy group, an aryloxy group, or a hydroxyl group; R₂₅, R₂₆ and R₂₇ each represents a hydrogen atom, an alkyl group, an aryl group, an aralkyl group, or an acyl group; and W₂ represents an oxygen atom, or a sulfur atom.
Although specific examples of these couplers are illustrated in JP-A-63-11939, the following compounds can be cited as more preferred ones.
The couplers represented by the foregoing general formulae (VI) to (X) are each incorporated in silver halide emulsion layer(s) to constitute a light-sensitive layer in an amount of, in general, from 0.1 to 1.0 mol, preferably from 0.1 to 0.5 mol, per mol of silver halide.
In incorporating a coupler as illustrated above into a light-sensitive layer, known various techniques can be applied in this invention. In general, oil-in-water dispersion processes known as an oil protection method can be used, wherein a coupler dissolved in a solvent is dispersed into an aqueous solution of gelatin containing a surfactant in the form of an emulsion, or water or an aqueous gelatin solution is admixed with a coupler solution containing a surfactant to convert the mixture into an oil-in-water dispersion through phase inversion. On the other hand, alkali-soluble couplers can be dispersed in accordance with a so-called Fischer's dispersion method. After a low boiling organic solvent is removed from a coupler dispersion using a distillation, noodle washing or ultrafiltration method, the dispersion may be mixed with a photographic emulsion.
As a dispersion medium for couplers as described above, high boiling organic solvents having a dielectric constant of from 2 to 20 (at 25°C) and a refractive index of from 1.3 to 1.5, and/or water-insoluble high molecular weight compounds can be used.
High boiling organic solvents which can be preferably used herein are represented by the following general formulae (A) to (E):
wherein W₁, W₂ and W₃ each represents a substituted or unsubstituted alkyl, cycloalkyl, alkenyl, aryl or heterocyclic group; W₄ represents W₁, OW₁, or SW₁; n represents an integer of 1 to 5, and when n is 2 or more, W₄'s may be the same or different; and in formula (E), a condensed ring may be formed by W₁ and W₂.
In addition to the high boiling organic solvents of formulae (A) to (E), water-immiscible compounds having a melting point of 100°C or lower and a boiling point of 140°C or higher can be used as a dispersion medium if only they are good solvents for couplers. A preferred melting point of such high boiling point organic solvents is 80°C or lower, and a preferred boiling point thereof is 160°C or higher, especially 170°C or higher.
Specific examples of high boiling organic solvents having a boiling point of 160°C or higher include phthalic acid alkyl esters (such as dibutyl phthalate, dioctyl phthalate, etc.), phosphoric acid esters (such as diphenyl phosphate, triphenyl phosphate, tricresyl phosphate, dioctylbutyl phosphate, etc.), citric acid esters (such as tributyl acetylcitrate), benzoic acid esters (such as octyl benzoate), alkylamides (such as diethyllaurylamide), fatty acid esters (such as dibutoxyethylsuccinate, dioctylazelate, etc.), and phenols (such as 2,4-di-t-amylphenol).
As examples of water-insoluble high molecular weight compounds, mention may be made of the compounds disclosed in JP-B-60-18978, columns 18-21, and vinyl polymers (including homopolymers and copolymers) containing as one monomer component an acrylamide or a methacrylamide.
More specifically, polymethylmethacrylate, polyethylmethacrylate, polybutylmethacrylate, polycyclohexylmethacrylate, poly(t-butylacrylamide) and the like can be given as suitable examples.
Together with these high boiling organic solvents and/or water-insoluble high molecular weight compounds, low boiling organic solvents having a boiling point of from 30°C to 150°C, with specific examples including lower alkyl acetates (e.g., ethyl acetate, butyl acetate), ethyl propionate, secondary butyl alcohol, methyl isobutyl ketone, β-ethoxyethylacetate, methyl cellosolve acetate and so on, can be used individually or as a mixture, if desired.
In this invention, an ultraviolet absorbent can be incorporated in any layer. It is desirable that an ultraviolet absorbent should be incorporated in a layer containing a cyan coupler represented by the foregoing general formula (VI) or (VII), or the adjacent layer thereto. Ultraviolet absorbents usable in this invention include compounds cited in Research Disclosure, No. 17643, Item VIII-C, and preferred ones are benzotriazole compounds represented by the following general formula (XI):
wherein R₂₈, R₂₉, R₃₀, R₃₁ and R₃₂ may be the same or different, each being a hydrogen atom, a halogen atom, a nitro group, a hydroxyl group, an alkyl group, an alkenyl group, an aryl group, an alkoxy group, an acyloxy group, an aryloxy group, an alkylthio group, an arylthio group, a mono- or dialkylamino group, an acylamino group, or a 5- or 6-membered oxygen- or nitrogen-containing heterocyclic group; and further, R₃₁ and R₃₂ may combine with each other to complete a 5- or 6-membered aromatic carbon ring. These groups may be substituted by any of groups allowed as a substituent for R₁ so long as they can have a substituent.
The compounds represented by the foregoing general formula (XI) can be used alone or as a mixture of two or more thereof.
Syntheses of the compounds represented by the foregoing general formula (XI) or other ultraviolet absorbent compound examples are described in JP-B-44-29620, JP-A-50-151149, JP-A-54-95233, U.S. Patent 3,766,205, EP 0057160, Research Disclosure, No. 22519 (1983, No. 225), JP-A-61-190537, and so on. In addition, high molecular weight ultraviolet absorbents disclosed in JP-A-58-111942, JP-A-58-178351, JP-A-58-181041, JP-A-59-19945 and JP-A-59-23344 can be used. Also, low molecular weight and high molecular weight ultraviolet absorbents can be used in combination.
Ultraviolet absorbents as described above, in analogy with the couplers, are dissolved in a high boiling organic solvent or/and a low boiling organic solvent, and then dispersed into a hydrophilic colloid. The proportion of a high boiling organic solvent to an ultraviolet absorbent does not have any particular limitation, but is generally within the range of 0 to 300 wt%. In dispersing an ultraviolet absorbent, it is desirable that compounds which are liquid at ordinary temperature should be used alone or in combination.
The combined use of the couplers which can be employed in this invention and the ultraviolet absorbents of the foregoing general formula (XI) can improve upon keeping quality, particularly light fastness, of developed dye images, especially a cyan image. These ultraviolet absorbents and cyan couplers may be coemulsified.
The ultraviolet absorbents may be used in any amount so long as it is enough to impart light stability to a cyan dye image, but the addition in too large an amount often causes yellow stain in the unexposed part (white part) of a color photographic material. Therefore, the coverage of the ultraviolet absorbents is preferably controlled to from 1 × 10⁻⁴ mol/m² to 2 × 10⁻³ mol/m², particularly from 5 × 10⁻⁴ mol/m² to 1.5 × 10⁻³ mol/m².
In a light-sensitive layer structure of ordinary color paper, the ultraviolet absorbents are incorporated in either or both, preferably both, of the layers adjacent to a cyan coupler-containing red-sensitive emulsion layer. In incorporating the ultraviolet absorbents into an interlayer sandwiched in between a green-sensitive layer and a red-sensitive layer, the ultraviolet absorbents emulsified together with color stain inhibitors may be used. When the ultraviolet absorbents are added to a protective layer, the other protective layer may be provided as the outermost layer. This protective layer can contain a matting agent having an arbitrary particle size, or the like.
In order to enhance the keeping quality of developed dye images, especially yellow and magenta dye images, various kinds of organic discoloration inhibitors or metal complex type discoloration inhibitors can be used in combination. Suitable examples of organic discoloration inhibitors include hydroquinone derivatives, gallic acid derivatives, p-alkoxyphenols, and p-hydroxyphenols. As for the dye image stabilizers, stain inhibitors and antioxidants, patents regarding them are cited in Research Disclosure, No. 17643, Items VII-I and VII-J. On the other hand, the discoloration inhibitors of metal complex type are described in Research Disclosure, No. 15162, and so on.
A number of compounds belonging to phenols, hydroquinones, hydroxychromans, hydroxycoumarans, hindered amines, and alkyl ethers, silyl ethers or hydrolyzable precursor derivatives of these compounds can be used for enhancing heat and light fastnesses of yellow color images. In particular, compounds represented by the following general formulae (XVIII) and (XIX) are effective for enhancing both light fastness and heat fastness of yellow color images produced from the couplers represented by the foregoing general formula (X):
wherein R₄₀ represents a hydrogen atom, an aliphatic group, an aromatic group, a heterocyclic group, or a substituted silyl group of formula
(wherein R₅₀, R₅₁ and R₅₂ may be the same or different, each being an aliphatic group, an aryl group, an aliphatic oxy group, or an aromatic oxy group, which may be substituted by any of groups allowed as a substituent for R₁); R₄₁, R₄₂, R₄₃, R₄₄ and R₄₅ may be the same or different, each being a hydrogen atom, an alkyl gorup, an aryl group, an alkoxy group, a hydroxyl group, mono- or dialkylamino group, an imino group, or an acylamino group; R₄₆, R₄₇, R₄₈ and R₄₉ may be the same or different, each being a hydrogen atom, an aliphatic group, an acyl group, an aliphatic or aromatic sulfonyl group, an aliphatic or aromatic sulfinyl group, oxy radical group, or a hydroxyl group; and A represents nonmetal atoms necessary to complete a 5-, 6- or 7-membered ring.
Syntheses of the compounds corresponding to general formulae (XVIII) and (XIX), or compound examples other than the above-cited ones are described in British Patents 1,326,889, 1,354,313 and 1,410,846, U.S. Patents 3,336,135 and 4,268,593, JP-B-51-1420, JP-B-52-6623, JP-A-58-114036 and JP-A-59-5246.
The compounds represented by general formulae (XVIII) and (XIX) may be used as a mixture of two or more thereof, or in combination with other conventionally known discoloration inhibitors.
The compounds represented by general formulae (XVIII) and (XIX) are used in amounts depending on the kind of a yellow coupler to be used in combination. Specifically, the desired end can be achieved by using these compounds in a proportion of 0.5 to 200 wt%, preferably 2 to 150 wt%, to the yellow coupler. It is desirable that the compounds of formulae (XVIII) and (XIX) should be emulsified together with the yellow coupler of formula (X).
The above-described various kinds of dye image stabilizers, stain inhibitors and antioxidants are also effective for an improvement in keeping quality of magenta dyes produced from the couplers represented by the foregoing general formula (VIII) and (IX). In particular, the group of compounds represented by general formulae (XX), (XXI), (XXII), (XXIII), (XXIV) and (XXV) are preferred over others because they can greatly enhance light fastness of the magenta images:

wherein R₆₀ has the same meaning as R₄₀ in general formula (XVIII); R₆₁, R₆₂, R₆₄ and R₆₅ may be the same or different, each being a hydrogen atom, an aliphatic group, an aryl group, an acylamino group, a mono- or dialkylamino group, an aliphatic or aromatic thio group, an aliphatic or aromatic oxycarbonyl group, or -OR₄₀; R₄₀ and R₆₁ may combine with each other to form a 5- or 6-membered ring; also, R₆₁ and R₆₂ may combine with each other to form a 5- or 6-membered ring; X represents a divalent linkage group; R₆₆ and R₆₇ may be the same or different, each being a hydrogen atom, an aliphatic group, an aryl group, or a hydroxyl group; R₆₈ represents a hydrogen atom, an aliphatic group, or an aryl group; R₆₆ and R₆₇ may combine with each other to form a 5- or 6-membered ring; M represents Cu, Co, Ni, Pd or Pt; when the substituents R₆₁ to R₆₈ each represents an aliphatic or aromatic group, they may further be substituted by any of the groups allowed as a substituent for R₁; n represents an integer from 0 to 3 and m represents an intger from 0 to 4, which each means the substitution number of R₆₂ or R₆₁, and when they are 2 or above, R₆₂'s or R₆₁'s may be the same or different.
In general formula (XXIV), representatives of preferred X's are
and so on, where R₇₀ represents a hydrogen atom or an alkyl group.
The substituent R₆₁ preferred in general formula (XXV) is a group capable of forming a hydrogen bond (e.g., an acylamino group, an aliphatic or aromatic oxycarbonyl group). It is desirable that at least one among the substituents R₆₂, R₆₃ and R₆₄ should be a hydrogen atom, a hydroxyl group, an alkyl group or an alkoxy group, and each of the substituents R₆₁ to R₆₈ should be a group containing at least 4 carbon atoms in all.
Syntheses of the above-described compounds and others are described in U.S. Patents 3,336,135, 3,432,300, 3,573,050, 3,574,627, 3,700,455, 3,764,337, 3,935,016, 3,982,944, 4,254,316 and 4,279,990, British Patents 1,347,556, 2,062,888, 2,066,975 and 2,077,455, JP-A-60-97353, JP-A-52-152225, JP-A-53-17729, JP-A-53-20327, JP-A-54-145530, JP-A-55-6321, JP-A-55-21004, JP-A-58-24141, JP-A-59-10539, JP-B-48-31625 and JP-B-54-12337.
Among discoloration inhibitors used to advantage in this invention, the compounds represented by general formulae (XX) to (XXIV) are each added in a proportion of 10 to 200 mol%, preferably 30 to 100 mol%, to magenta couplers to be used in this invention. On the other hand, the compounds represented by general formula (XXV) are added in a proportion of 1 to 100 mol%, preferably 5 to 40 mol% to magenta couplers to be used in this invention. It is desirable that these compounds are coemulsified with the magenta couplers.
It is desirable in this invention that the following compounds should be used together with the foregoing couplers, particularly with pyrazoloazole type couplers.
More specifically, it is desirable to use a compound (Q) capable of producing a chemically inert and substantially colorless compound by chemically binding to an aromatic amine developing agent remaining after color development, and/or a compound (R) capable of producing a chemically inert and substantially colorless compound by chemically binding to the oxidation product of an aromatic amine color developing agent remaining after color development in combination or independently, e.g., for the purpose of preventing generation of stain and other side reactions attributable to the production of developed dyes by the reaction between couplers and a color developer or the oxidation product thereof remaining in the film upon storage after photographic processing.
Compounds preferred as the compound (Q) are those undergoing a reaction with p-anisidine under such a condition that a rate constant in the second order reaction, k2, ranges from 1.0 ℓ/mol sec to 1 × 10⁻⁵ ℓ/mol sec (in 80°C trioctyl phosphate). The rate constant in the second order reaction can be determined in accordance with the method described in JP-A-63-158545.
When k2 is greater than the above-defined range, the compounds themselves are unstable, so it frequently happens that they decompose by the reaction with gelatin or water. On the other hand, when k2 is smaller than the above-defined range, the reaction with the residual aromatic amine developing agent is slow, and as a result of such a slow reaction, it frequently happens that the end of this compound, or the prevention of the side reaction of the residual aromatic amine developing agent, cannot be achieved.
Compounds which are more preferred as compound (Q) can be presented by the following general formula (QI) or (QII):
R₁-(A)_n-X (QI)
R₂-
=Y (QII)

wherein R₁ and R₂ each represents an aliphatic group, an aromatic group, or a heterocyclic group; n represents 1 or 0; A represents a group capable of forming a chemical bond by reacting with an aromatic amine type developer; X represents a group capable of being eliminated by the reaction with an aromatic amine type developer; B represents a hydrogen atom, an aliphatic group, an aromatic group, a heterocyclic group, an acyl group, or a sulfonyl group; and Y represents a group capable of accelerating the addition of an aromatic amine developing agent to the compound of general formula (QII); and further, R₁ and X, and Y and R₂ or B, respectively, may combine with each other to complete a cyclic structure.
The chemical binding to the residual aromatic amine developing agent can typically be effected through a substitution reaction or an addition reaction.
Specific examples of compounds represented by general formulae (QI) and (QII) are disclosed in JP-A-63-158545, JP-A-62-283338, European Patent Nos. 298,321 and 277,589, and so on.
On the other hand, those preferred as the compound (R), which produces a chemically inert and colorless compound by chemically binding to the oxidation product of an aromatic amine type developing agent remaining after color development, are represented by the following general formula (RI):
R-Z (RI)
wherein R represents an aliphatic group, an aromatic group, or a heterocyclic group; and Z represents a nucleophilic group, or a group capable of releasing a nucleophilic group through decomposition in the photographic material. Preferred compounds represented by general formula (RI) contain as Z such groups as to have a Rearson's nucleophilicity "CH₃I" value (R.G. Rearson et al., J. Am. Chem. Soc., 90, 319 (1968) of 5 or above, or those derived from such groups.
Specific examples of preferred compounds of general formula (RI) are disclosed in European Patent Nos. 255,722, 298,321 and 277,589, JP-A-62-143048, JP-A-62-229145, Japanese Patent Application No. 63-136724, JP-A-1-57259, and so on.
In addition, the details of the combined use of the foregoing compounds (R) and (Q) are disclosed in European Patent 277,589.
As a binder or a protective colloid for photographic emulsions, gelatin is used to advantage. Also, hydrophilic colloids other than gelatin can be used.
Specifically, proteins such as gelatin derivatives, graft copolymers prepared from gelatin and other macromolecules, albumin, casein, etc.; sugar derivatives such as cellulose derivatives (e.g., hydroxyethyl cellulose, carboxymethyl cellulose, cellulose sulfate), sodium alginate, starch derivatives, etc.; and various kinds of synthetic hydrophilic high molecular compounds such as homo- and copolymers including polyvinyl alcohol, partial acetal of polyvinyl alcohol, poly-N-vinylpyrrolidone, polyacrylic acid, polymethacrylic acid, polyacrylamide, polyvinylimidazole, polyvinylpyrazole and the like can be used.
Gelatin which can be used in this invention may be either lime-processed or acid-processed. Details of the preparation of gelatin are described in Arthur Veis, The Macromolecular Chemistry of Gelatin, Academic Press (1964).
The term "reflecting support" as used in this invention refers to a support which can enhance reflectivity to contribute to clarification of dye images formed in silver halide emulsion layer, and includes supporting materials on which hydrophobic resins containing light-reflecting substances, such as titanium oxide, zinc oxide, calcium carbonate, calcium sulfate, etc., in a dispersed condition are coated, and films of hydrophobic resins in which light-reflecting substances are dispersed. Specific examples thereof include baryta paper, polyethylene-coated paper, synthetic paper of polypropylene type, and reflecting layer-laminated or reflecting substance-containing transparent supports. Suitable examples of such transparent supports include glass plate, films of polyesters such as polyethylene terephthalate, cellulose triacetate, cellulose nitrate, etc., polyamide films, polycarbonate films, polystyrene films, vinyl chloride resin films, and so on. The support to be used can be properly chosen from the above-cited ones depending on the end use purpose of the photographic material of this invention.
As for the light-reflecting substances to be used, it is desirable that white pigments should be thoroughly kneaded in the presence of a surfactant, and pigment grains the surfaces of which have been treated with a di- to tetrahydric alcohol should be used.
An occupied area rate (%) of fine grained white pigment per specified unit area can be determined most typically by dividing the observed area into neighboring unit areas of 6 × 6 square microns, and measuring an occupied area rate Ri (%) of fine grains projected on each unit area. The variation coefficient of the occupied area rate (%) can be defined as the ratio of the standard deviation of Ri, represented by s, to the mean of Ri, represented by R. The number of unit areas to be examined as the subject, represented by n, is preferably 6 or more. Accordingly, the variation coefficient s/R can be determined according to the equation:
In this invention, a variation coefficient of the occupied area rate (%) of fine grained pigment is preferably 0.15 or less, particularly preferably 0.12 or less. When the variation coefficient is 0.08 or less, a dispersed condition of the grains can be said to be "uniform" in a substantial sense.
When the photographic material of this invention contains dyes and ultraviolet absorbents in hydrophilic colloid layers, they may be mordanted by cationic polymers or so on. For example, the polymers described in British Patent 685,475, U.S. Patents 2,675,316, 2,839,401, 2,882,156, 3,048,487, 3,184,309 and 3,445,231, West German Patent Application (OLS) 1,914,362, JP-A-50-47624, JP-A-50-71332 and so on can be used as a mordant.
The photographic material of this invention may contain hydroquinone derivatives, aminophenol derivatives, gallic acid derivatives, ascorbic acid derivatives and so on as color fog inhibitors. Specific examples of these derivatives are disclosed in U.S. Patents 2,360,290, 2,336,327, 2,403,721, 2,418,613, 2,675,314, 2,701,197, 2,704,713, 2,728,659, 2,732,300 and 2,735,765, JP-A-50-92988, JP-A-50-92989, JP-A-50-93928, JP-A-50-110337, JP-A-52-146235, JP-B-50-23813, and so on.
Optionally, the photographic material of this invention may contain a fine grained silver halide emulsion having substantially no sensitivity (e.g., silver chloride, silver bromide or silver chlorobromide emulsion having an average grain size of 0.20 µm or less) in silver halide emulsion layers or other hydrophilic colloid layers.
This invention can be applied to various kinds of photosensitive materials, and representatives thereof are color paper, color positive films and so on. In addition, this invention can be applied to black-and-white photographic materials of the kind which utilize a mixture of thre color couplers, as described in Research Disclosure, No. 17123 (July, 1978).
A color developer which can be used for development processing of the photographic material of this invention is preferably an alkaline aqueous solution containing as a main component a color developing agent of an aromatic primary amine type. As for the color developing agent, p-phenylenediamine compounds are preferably used, though aminophenol compounds also are useful. Typical examples of p-phenylenediamine type color developing agents include 3-methyl-4-amino-N,N-diethylaniline, 3-methyl-4-amino-N-ethyl-N-β-hydroxyethylaniline, 3-methyl-4-amino-N-ethyl-N-β-methanesulfonamidoethylaniline, 3-methyl-4-amino-N-ethyl-N-β-methoxyethylaniline, and the sulfates, hydrochlorides or p-toluenesulfonates of the above-cited anilines. These compounds may be used as mixture of two or more thereof, if desired.
Further, the color developer generally contains pH buffering agents, such as carbonates, borates or phosphates of alkali metals, and development inhibitors or antifoggants, such as bromides, iodides, benzimidazoles, benzothiazoles or mercapto compounds. Furthermore, the color developer may optionally contain various kinds of preservatives, such as hydroxylamine, diethylhydroxylamine, sulfites, hydrazines, phenylsemicarbazides, triethanolamine, catechol sulfonic acids, and triethylenediamine(1,4-diazabicyclo[2,2,2]octane); organic solvents, such as ethylene glycol or diethylene glycol; development accelerators such as benzyl alcohol, polyethylene glycol, quaternary ammonium salts or amines; dye-forming couplers; competing couplers; fogging agents such as sodium borohydride; auxiliary developers such as 1-phenyl-3-pyrazolidone; viscosity imparting agents; and various chelating agents such as aminopolycarboxylic acids, aminopolyphosphonic acids, alkylphosphonic acids and phosphonocarboxylic acids, with typical representatives including ethylenediaminetetraacetic acid, nitrilotriacetic acid, diethylenetriaminepentaacetic acid, cyclohexanediaminetetraacetic acid, hydroxyethyliminodiacetic acid, 1-hydroxyethylidene-1,1-diphosphonic acid, nitrilo-N,N,N-trimethylenephosphonic acid, ethylenediamine-N,N,N′,N′-tetramethylenephosphonic acid, ethylenediaminedi(o-hydroxyphenylacetic acid) and salts of these acids.
In carrying out a reversal processing, black-and-white development is generally performed prior to color development. A black-and-white developer usable therein contains known black-and-white developing agents, such as dihydroxybenzenes (e.g., hydroquinone), 3-pyrazolidones (e.g., 1-phenyl-3-pyrazolidone) or aminophenols (e.g., N-methyl-p-aminophenol), individually or in combination.
These color developers and black-and-white developers are generally replenished in a quantity of 3 liters or less per square meter of color photographic material processed, though the replenishing quantity depends on the kind of color photographic material processed. When a replenisher containing bromide ion in a reduced concentration is used, the quantity of the replenisher can be decreased to 500 ml or less per square meter of color photographic material processed. When a reduced quantity of replenisher is used, it is desirable to prevent vaporization and air oxidation from occurring in the developing bath by minimizing the contact area between the developer and air. Also, the quantity of replenisher can be reduced by adopting means for suppressing accumulation of bromide ion in the developing bath.
After color development, photographic emulsion layers are, in general, subjected to a bleach processing. The bleach processing may be carried out simultaneously with a fixing processing (a bleach-fix processing), or separately therefrom. For the purpose of speeding up the photographic processing, the bleach processing may be succeeded by the bleach-fix processing. Also, the fixing processing may be succeeded by the bleach-fix processing, or the bleach-fix processing may be succeeded by the bleach processing, if desired. Examples of bleaching agents which can be used include compounds of polyvalent metals, such as Fe(III), Co(III), Cr(VI), Cu(II), etc.; peroxy acids; quinones; nitro compounds; and so on. More specifically, ferricyanides; dichromates; organic complex salts formed by Fe(III) or Co(III) and aminopolycarboxylic acids, such as ethylenediaminetetraacetic acid, diethylenetriaminepentaacetic acid, cyclohexanediaminetetraacetic acid, methyliminodiacetic acid, 1,3-diaminopropanetetraacetic acid, glycol ether diaminetetraacetic acid, etc., citric acid, tartaric acid, malic acid, or so on; persulfates; hydrobromides; permanganates; nitrobenzenes; and so on can be cited as representatives of suitable bleaching agents. Among these bleaching agents, aminopolycarbonatoferrate(III) complexes including ethylenediaminetetraacetonatoferrate(III) complex, and persulfates are preferred over others from the standpoints of rapid processing and prevention of environmental pollution. In addition, aminopolycarbonatoferrate(III) complexes are particularly useful in not only a bleaching bath, but also a bleach-fix bath.
In the bleaching bath, the bleach-fix bath and the prebaths thereof, bleach accelerators can be used, if needed.
Specific examples of useful bleach accelerators include compounds containing a mercapto group or a disulfide linkage, as described in U.S. Patent 3,893,858, West German Patents 1,290,812 and 2,059,988, JP-A-53-32736, JP-A-53-57831, JP-A-53-37418, JP-A-53-72623, JP-A-53-95630, JP-A-53-95631, JP-A-53-104232, JP-A-53-124424, JP-A-53-141623, JP-A-53-28426, Research Disclosure, No. 17129 (July, 1978), and so on; thiazolidine derivatives described in JP-A-50-140129; thiourea derivatives described in JP-B-45-8506, JP-A-52-20832, JP-A-53-32735, and U.S. Patent 3,706,561; iodides described in West German Patent 1,127,715, and JP-A-58-16235; polyoxyethylene compounds described in West German Patents 996,410 and 2,748,430; polyamine compounds described in JP-B-45-8836; the compounds disclosed in JP-A-49-42434, JP-A-49-59644, JP-A-53-94927, JP-A-54-35727, JP-A-55-26506 and JP-A-58-163940; and bromide ion. Of these bleach accelerators, the compounds containing a mercapto group or a disulfide linkage are preferred in respect of their greater acceleration effect. In particular, the compounds described in U.S. Patent 3,893,858, West German Patent 1,290,812 and JP-A-53-95630 are preferred over others. In addition, the compound disclosed in U.S. Patent 4,552,834 are also effective. The bleach accelerators may be incorporated in the photographic materials.
As examples of fixers which can be used, mention may be made of thiosulfates, thiocyanates, thioether compounds, thioureas, a large amount of iodide, and so on. Of these fixers, thiosulfates are generally used, and the most widely used one is ammonium thiosulfate. Examples of preservatives suitable for a bleach-fix bath include sulfites, bisulfites, or adducts of carbonyl compounds and bisulfites.
After a desilvering step, the silver halide color photographic material of this invention is, in general, subjected to a washing step and/or a stabilizing step. The volume of washing water required in the washing step can be determined variously depending on the characteristics of photographic materials to be processed (e.g., on what kinds of couplers are incorporated therein), end use purposes of the photographic materials to be processed, the temperature of washing water, the number of washing tanks (stage number), the way of replenishing washing water (as to, e.g., whether a current of water flows in the counter direction, or not), and other various conditions. Of these conditions, the relation between the number of washing tanks and the volume of washing water in the multistage countercurrent process can be determined according to the methods described in Journal of the Society of Motion Picture and Television Engineers, Vol. 64, pages 248-253 (May, 1955).
According to the multistage countercurrent process described in the above-cited literature, the volume of washing water can be sharply decreased. However, the process has disadvantages, e.g., in that bacteria propagate themselves in the tanks because of an increase in the staying time of water in the tanks, and a suspended matter produced from the bacteria sticks to photographic materials processed therein. In the processing of the color photographic material of this invention, the method of reducing calcium and magnesium ion concentrations, which is disclosed in JP-A-62-288838, can be employed to great advantage as the means of solving the above-described problem. Further, bactericides such as isothiazolone compounds and thiabendazoles as disclosed in JP-A-57-8542, chlorine-containing germicides such as sodium salt of chlorinated isocyanuric acid, and benzotriazoles, as described in Hiroshi Horiguchi, Bohkin Bohbai Zai no Kagaku (which means "Chemistry of Antibacteria and Antimolds"), Biseibutsu no Mekkin Sakkin Bohbai Gijutsu (which means "Arts of Sterilizing and Pasteurizing Microbe, and Proofing against Mold"), compiled by Eisei Gijutsu Kai, and Bohkin and Bohbai Zai Jiten (which means "Thesaurus of Antibacteria and Antimolds"), compiled by Nippon Bohkin Bohbai Gakkai.
Washing water to be used in the processing of the photographic materials of the present invention is adjusted to pH 4 to 9, preferably to pH 5 to 8. The washing temperature and washing time, though can be chosen variously depending on the characteristics and the intended use of the photographic materials to be washed, and are generally chosen from 20 sec to 10 min at 15°C to 45 °C, preferably 30 sec to 5 min at 25°C to 40°C.
Also, the photographic materials of the present invention can be processed directly with a stabilizing solution instead of using the above-described washing water. Known methods, such as those which are disclosed in JP-A-57-8543, JP-A-58-14834 and JP-A-60-220345, can be applied to the stabilization step in the present invention.
In some cases, the stabilization step is also performed subsequently to the above-described washing step. To this stabilizing bath also, various kinds of chelating agents and antimolds can be added. The washing water and/or the stabilizing solution overflowing the processing baths with the replenishing thereof can also be reused in other steps such as the desilvering step.
For the purpose of simplification and speed up of the photographic processing, a color developing agent may be incorporated into the silver halide color photo graphic material of this invention. Therein, it is desirable that the color developing agent should be used in the form of precursors of various types. As instances, the compounds of an indoaniline type disclosed in U.S. Patent 3,342,599, the compounds of a Schiff base type disclosed in U.S. Patent 3,342,599 and Research Disclosure, Nos. 14850 and 15159, the aldol compounds described in Research Disclosure, No. 13924, the metal complex salts disclosed in U.S. Patent 3,719,492, and the urethane compounds disclosed in JP-A-53-135628 can be cited.
In the silver halide color photographic materials of this invention, various 1-phenyl-3-pyrazolidones each may be incorporated for the purpose of accelerating color development, if desired. Typical examples of such compounds are described in JP-A-56-64339, JP-A-57-144547, JP-A-58-115438, and so on.
The temperature of each processing bath used in this invention can range from 10°C to 50°C. Though a standard temperature is within the range of 33°C to 38°C, temperatures higher than standard ones can be adopted for reduction of the processing time through acceleration of the processing, while those lower than standard ones enable the achievements of improved image quality and enhanced stability of the processing bath. Moreover, a processing which utilizes cobalt intensification or hydrogen peroxide intensification as disclosed in West German Patent 2,226,770 or U.S. Patent 3,674,499 may be carried out for the purpose of saving silver.
In various kinds of processing baths, a heater, a temperature sensor, a liquid level sensor, a circulating pump, a filter, a floating lid, a squeegee and so on may be installed.
This invention will now be illustrated in more detail by reference to the following examples. However, the invention should not be construed as being limited to these embodiments.

EXAMPLE 1

A silver halide emulsion (A) for a blue-sensitive silver halide emulsion layer was prepared in the following manner.

Solution 1

H₂O 1,000 ml

NaCl 9.07 g

KBr 0.07 g

Gelatin 25.8 g

Sulfuric Acid (1 N) 19.7 ml

Solution 3

KBr 17.0 g

NaCl 0.25 g

Water to make 129.3 ml

Solution 4

AgNO₃ 25 g

NH₄NO₃ (50 wt% aq. soln.) 0.5 ml

Water to make 133.3 ml

Solution 5

KBr 52.07 g

NaCl 5.4 g

K₂IrCl₆ (0.001 wt% aq. soln.) 2.0 ml

Water to make 283.3 ml

Solution 6

AgNO₃ 100 g

NH₄NO₃ (50 wt% aq. soln.) 1.5 ml

Water to make 286 ml
Solution 1 was heated to 70°C, and thereto was added Solution 2. Thereto, Solution 3 and Solution 4 were added at the same time over a 40 minute period. After a 10 minute lapse, Solution 5 and Solution 6 were further added thereto over a 25 minute period at the same time. After a lapse of 5 minutes from the conclusion of the addition, the temperature of the reaction mixture was lowered, and then desalted. Thereto, water and dispersant gelatin were added, and the pH was adjusted to 6.15. Thus, a monodisperse cubic silver chlorobromide emulsion (A) having an average grain size of 0.88 µm, a variation coefficient (the value obtained by dividing the standard deviation by the average grain size, i.e., s/d) of 0.06 and a bromide cotent of 79 mol% was obtained. This emulsion was chemically sensitized with triethylurea under optimum conditions.
In addition, another silver halide emulsion (B) for the blue-sensitive silver halide emulsion layer, silver halide emulsions (C) and (D) for a green-sensitive silver halide emulsion layer, and silver halide emulsions (E) and (F) for a red-sensitive silver halide emulsion layer were prepared in the same manner as described above, except that quantities of the ingredients, reaction temperatures and addition times were changed variously.

Crystal forms, average grain sizes, halide compositions and variation coefficients of the silver halide emulsions obtained are shown below.

Emulsion Name	Crystal Form	Grain Size	Br Content	Variation Coefficient
		(µm)	(mol%)
(A)	Cube	0.88	79	0.06
(B)	Cube	0.65	80	0.06
(C)	Cube	0.46	90	0.09
(D)	Cube	0.35	90	0.09
(E)	Cube	0.48	74	0.10
(F)	Cube	0.34	74	0.10

To the silver halide emulsions (A) and (B), the spectral sensitizer (Sen-1) was added in an amount of 3.8 × 10⁻⁴ mol per mol of silver halide. To the silver halide emulsions (C) and (D), the spectral sensitizers (Sen-2) and (Sen-3) were added in amounts of 2.1 × 10⁻⁴ mol and 4.2 × 10⁻⁵ mol, respectively, per mol of silver halide. To the silver halide emulsions (E) and (F) was added the spectral sensitizer (Sen-4) in an amount of 1.8 × 10⁻⁴ mol per mol of silver halide.
On a paper support laminated with a polyethylene film on both sides thereof were coated the layers described below in this order to prepare Sample 101.

Constituent Layers:

The ingredients used and their coverages expressed in terms of g/m² are described below, except that the coverage of silver halide is expressed on a silver basis.

Support

Polyethylene Laminated Paper (containing a white pigment (TiO₂) and a bluish dye (ultramarine) on the first layer side)
Samples 102 to 118 were prepared in the same manner as Sample 101, except the dyes in the fourth layer, and the spectral sensitizer, the water-soluble bromide and supersensitizer in the fifth layer were changed. The constituents of these samples are shown in Table 1.

Samples 101 to 123 were each exposed by means of a sensitometer (produced by Fuji Photo Film Co., Ltd., and equipped with a light source the color temperature of which was 3,200°K) through an optical wedge for sharpness measurement under such a condition as to convert the hue of the exposure to gray using yellow and magenta filters. The exposure time was 1 second. After exposure, each sample was subjected to the photographic processing including the following steps.

Processing Step	Temperature	Time
	(°C)
Color Development	33	3 min 30 sec
Bleach-Fix	33	1 min 30 sec
Washing (1)	30-34	60 sec
Washing (2)	30-34	60 sec
Washing (3)	30-34	60 sec
Drying	70-80	50 sec

(The washing steps were performed in accordance with a three tank countercurrent process from the washing step (3) to the washing step (1).)

The compositions of the processing solutions used were as follows.

Color Developer:
Water	800 ml
Diethylenetriaminepentaacetic Acid	1.0 g
Nitrilotriacetic Acid	1.5 g
Benzyl Alcohol	15 ml
Diethylene Glycol	10 ml
Sodium Sulfite	2.0 g
Potassium Bromide	0.5 g
Potassium Carbonate	30 g

N-Ethyl-N-(β-methanesulfonamidoethyl)-3-methyl-4-aminoaniline Sulfate	5.0 g
Hydroxylamine Sulfate	4.0 g
Brightening Agent (Whitex 4B, produced by Sumitomo Chemical Co., Ltd.)	1.0 g
Water to make	1,000 ml
pH (at 25°C)	10.20

Bleach-Fix Bath:
Water	400 ml
Ammonium Thiosulfate (70 wt% aq. soln.)	150 ml
Sodium Sulfite	18 g
Ammonium Ethylenediaminetetraacetatoferrate(III)	55 g
Disodium Ethylenediaminetetraacetate	5 g
Water to make	1,000 ml
pH (at 25°C)	6.70

The results of the measurement of the sharpness of each processed sample are shown in Table 2.

The sharpness is a quantity representing the acuity of the outline of an image and the ability to draw fine images. Herein, the value called CTF was employed as the measure of sharpness. CTF refers to the attenuation rate of the amplitude as a function of spatial frequency in harmonic analysis of a square-wave pattern. In Table 2, the sharpness is expressed in terms of CTF (%) value at the spatial frequency of 15 lines/mm, so a greater value shown in the table means that the corresponding sample has a better sharpness.

TABLE 2

Sample No.	Sharpness of Red-Sensitive Layer
101 (Comparison)	20.8
102 ( " )	25.4
103 ( " )	24.2
104 ( " )	23.9
105 ( " )	32.5
106 ( " )	30.8
107 ( " )	22.6
108 ( " )	31.5
109 ( " )	30.0
110 (Invention)	34.0
111 ( " )	32.9
112 (Comparison)	38.4
113 ( " )	36.8
114 ( " )	37.4
115 ( " )	35.5
116 (Invention)	40.7
117 ( " )	39.8
118 (Comparison)	29.9
119 (Invention)	34.4
120 ( " )	36.2
121 ( " )	36.0
122 ( " )	41.2
123 ( " )	43.2

It is clear from Table 2 that Samples 110, 111, 116, 117, and 119 to 123 in which the spectral sensitizers and the water-soluble bromides of this invention were incorporated were superior in sharpness to Comparative Samples 101 to 109, 112 to 115 and 118. Among the samples prepared in accordance with this invention, Samples 116, 117, 122 and 123 in which both potassium bromide and supersensitizers of this invention were additionally contained were superior to the other samples. Even when the dyes and the bromides of this invention are used, on the other hand, the effect produced thereby was small when the amount used was small, as seen in Sample 118.

EXAMPLE 2

The same samples as prepared in Example 1, from Sample 101 to 123, were each exposed in the same manner as in Example 1, and then subjected to the processing steps described below.

Processing Step	Temperature	Time
	(°C)
Color Development	37	3 min 30 sec
Bleach-Fix	33	1 min 30 sec
Washing (1)	30-34	60 sec
Washing (2)	30-34	60 sec
Washing (3)	30-34	60 sec
Drying	70-80	60 sec

The compositions of the processing solutions used were as follows.

Color Developer:
Water	800 ml
Diethylenetriaminepentaacetic Acid	1.0 g
Nitrilotriacetic Acid	2.0 g
Benzyl Alcohol	15 ml
Diethylene Glycol	10 ml
Sodium Sulfite	2.0 g
Potassium Bromide	1.0 g
Potassium Carbonate	30 g

N-Ethyl-N-(β-methanesulfonamidoethyl)-3-methyl-4-aminoaniline Sulfate	4.5 g
Hydroxylamine Sulfate	3.0 g
Brightening Agent (Whitex 4B, produced by Sumitomo Chemical Co., Ltd.)	1.0 g
Water to make	1,000 ml
pH (at 25°C)	10.25

Bleach-Fix Bath:
Water	400 ml
Ammonium Thiosulfate (70%)	150 ml
Sodium Sulfite	18 g
Ammonium Ethylenediaminetetraacetatoferrate(III)	55 g
Disodium Ethylenediaminetetraacetate	5 g
Water to make	1,000 ml
pH (at 25°C)	6.70

As for the sharpness of the processed samples, in analogy with the evaluation results in Example 1, the samples of this invention proved to be more excellent.

EXAMPLE 3

The same samples as prepared in Example 1, from Samples 101 to 118, were each exposed in the same manner as in Example 1, and then subjected to the processing step described below.

Processing Step	Temperature	Time
	(°C)
Color Development	38	1 min 40 sec
Bleach-Fix	35	60 sec
Rinsing (1)	33-35	20 sec
Rinsing (2)	33-35	20 sec
Rinsing (3)	33-35	20 sec
Drying	70-80	50 sec

The compositions of the processing solutions used were as follows.

Color Developer:
Water	800 ml
Diethylenetriaminepentaacetic Acid	1.0 g
Nitrilotriacetic Acid	2.0 g
1-Hydroxyethylidene-1,1-diphosphonic Acid	2.0 g
Benzyl Alcohol	16 ml
Diethylene Glycol	10 ml
Sodium Sulfite	2.0 g
Potassium Bromide	0.5 g
Potassium Carbonate	30 g

N-Ethyl-N-(β-methanesulfonamidoethyl)-3-methyl-4-aminoaniline Sulfate	5.5 g
Hydroxylamine Sulfate	2.0 g
Brightening Agent (Whitex 4B, produced by Sumitomo Chemical Co., Ltd.)	1.50 g
Water to make	1,000 ml
pH (at 25°C)	10.20

Bleach-Fix Bath:
Water	400 ml
Ammonium Thiosulfate (70 wt% aq. soln.)	80 ml
Sodium Sulfite	24 g
Ammonium Ethylenediaminetetraacetatoferrate(III)	30 g
Disodium Ethylenediaminetetraacetate	5 g
Water to make	1,000 ml
pH (at 25°C)	6.50

Rinsing Bath:

Ion exchanged water (calcium and magnesium ion concentration: below 3 ppm, respectively)
As for the sharpness of the processed samples, in analogy with the evaluation results in Example 1, the samples of this invention proved to be more excellent.

EXAMPLE 4

The same sample as prepared in Example 1, from Sample 101 to Sample 123 (except Sample 118), were allowed to stand for 2 days under the condition of 50°C, 80% relative humidity (RH). Thereafter, each of them and their respective fresh samples were exposed, and subjected to the same processing steps as in Example 1. The exposure was performed through an optical wedge separated into three colors, red, green and blue. The exposure time was 0.1 second, and the quantity of the exposure was 250 CMS.

The results obtained are shown in Table 3. The freshness keeping quality was expressed in terms of the difference between relative sensitivities (determined from the reciprocal of the exposure to impart the optical density of 1.0) of the fresh sample and the sample after a 2 day lapse under 50°C, 80% RH. A smaller value of the difference means that the corresponding sample has a better freshness keeping quality.

TABLE 3

Sample No.	Freshness Keeping Quality of Red-Sensitive Layer
101 (Comparison)	45
102 ( " )	35
103 ( " )	37
104 ( " )	40
105 ( " )	22
106 ( " )	25
107 ( " )	48
108 ( " )	25
109 ( " )	28
110 (Invention)	16
111 ( " )	20
112 (Comparison)	8
113 ( " )	10
114 ( " )	12
115 ( " )	12
116 (Invention)	5
117 ( " )	8
119 ( " )	16
120 ( " )	12
121 ( " )	11
122 ( " )	3
123 ( " )	3

As can be seen from Table 3, the samples of this invention have turned out to be excellent in freshness keeping quality.

EXAMPLE 5

Silver halide emulsions (G) to (I) described below were prepared. Crystal forms, average grain sizes, halide compositions and variation coefficients of these emulsions (G) to (I) are shown below. The remainder in each halogen composition consisted of bromide, and the bromide was present in part of each grain in a localized condition.

Emulsion Name Crystal Form Grain Size Cl Content Variation Coefficient

(µm) (mol%)

(G) Cube 0.90 99.4 0.08

(H) Cube 0.42 98.8 0.07

(I) Cube 0.37 98.3 0.08
To the silver halide emulsions (G), the spectral sensitizers (Sen-1) and (Sen-5) were added in amounts of 1.7 × 10⁻⁴ mol and 1.6 × 10⁻⁴ mol, respectively, per mol of silver halide. To the silver halide emulsions (H), the spectral sensitizers (Sen-2) and (Sen-3) were added in amounts of 4.0 × 10⁻⁴ mol and 7.8 × 10⁻⁵ mol, respectively, per mol of silver halide. To the silver halide emulsions (I) was added the spectral sensitizer (Sen-4) in an amount of 7.8 × 10⁻⁵ mol per mol of silver.
On a paper support laminated with a polyethylene film on both sides thereof were coated the layers described below in this order to prepare Sample 201.

Constituent Layers:

Support

Polyethylene Laminated Paper (containing a white pigment (TiO₂) and a bluish dye (ultramarine) on the first layer side)
The symbols of the above-described ingredients have the same meaning as in Example 1, respectively. As for the ingredients other than those used in Example 1, chemical structures thereof are illustrated below.
Samples 202 to 221 were prepared in the same manner as Sample 201, except the dyes in the fourth layer, and the spectral sensitizer, the water-soluble bromide and the supersensitizer in the fifth layer were changed. The constituents of these samples are shown in Table 4.
The above-described samples were each subjected to the same exposure for sharpness measurement as in Example 1, and then to the photographic processing including the following steps.

Processing Step Temperature Time

(°C) (sec)

Color Development 38 45

Bleach-Fix 30-36 45

Rinsing (1) 30-37 30

Rinsing (2) 30-37 30

Rinsing (3) 30-37 30

Drying 70-80 60

(The washing steps were performed in accordance with a three tank countercurrent process from the washing step (3) to the washing step (1).)

The compositions of the processing solutions used were as follows.

Color Developer:
Water	800 ml
Ethylenediamine-N,N,N′,N′-tetramethylenephosphonic Acid	3.0 g
N,N-Di(carboxymethyl)hydrazine	4.5 g
Sodium Chloride	3.5 g
Potassium Bromide	0.025 g
Potassium Carbonate	25.0 g

N-Ethyl-N-(β-methanesulfonamidoethyl)-3-methyl-4-aminoaniline Sulfate	5.0 g
Brightening Agent (Whitex 4B, produced by Sumitomo Chemical Co., Ltd.)	1.2 g
Water to make	1,000 ml
pH (at 25°C)	10.05

Bleach-Fix Bath:
Water	400 ml
Ammonium Thiosulfate (55 wt% aq. soln.)	100 ml
Sodium Sulfite	17 g
Ammonium Ethylenediaminetetraacetatoferrate(III)	55 g
Disodium Ethylenediaminetetraacetate	5 g
Ammonium Bromide	40 g
Clacial Acetic Acid	9 g
Water to make	1,000 ml
pH (at 25°C)	5.80

Rinsing Bath:

Ion exchanged water (calcium and magnesium ion concentration: below 3 ppm, respectively)
The results of the measurement of the sharpness of each processed sample are shown in Table 5.
It is clear from Table 5 that the samples prepared in accordance with this invention were superior in sharpness to the comparative samples. Among the samples prepared in accordance with this invention, Samples 216, 217, 220 and 221 in which both potassium bromide and supersensitizer were additionally contained were superior to the other samples.

EXAMPLE 6

Freshness keeping qualities of Samples 201 to 221 prepared in Example 5 were evaluated in the same way as in Example 4. As for the photographic processing, the samples each were subjected to the same processing steps as in Example 5. The results obtained are shown in Table 6.

TABLE 6

Sample No.	Freshness Keeping Quality of Red-Sensitive Layer
201 (Comparison)	52
202 ( " )	38
203 ( " )	40
204 ( " )	48
205 ( " )	20
206 ( " )	28
207 ( " )	55
208 ( " )	20
209 ( " )	25
210 (Invention)	18
211 ( " )	20
212 (Comparison)	10
213 ( " )	12
214 ( " )	12
215 ( " )	15
216 (Invention)	6
217 ( " )	8
218 ( " )	15
219 ( " )	14
220 ( " )	4
221 ( " )	5

As can be seen from Table 6, the samples of this invention have turned out to be excellent in freshness keeping quality.

EXAMPLE 7

On a paper support laminated with a polyethylene film on both sides thereof were coated the layers described below in this order to prepare Sample 301.

Constituent Layers:

Support

Polyethylene Laminated Paper (containing a white pigment (TiO₂) and a bluish dye (ultramarine) on the first layer side)
Sample 301 was evaluated by the same experiments as made in Example 5 and Example 6. As the results, it has turned out to have satisfactory photographic properties.
In accordance with the embodiments of this invention, silver halide color photographic materials which produce color images excellent in sharpness, and have excellent freshness keeping quality can be obtained.
While the invention has been described in detail and with reference to specific embodiments thereof, it will be apparent to one skilled in the art that various changes and modifications can be made therein without departing from the spirit and scope thereof.

Claims

1. A silver halide color photographic material having on a support hydrophilic colloidal layers containing at least one light-sensitive silver halide emulsion layer and at least one light-insensitive layer, one of the silver halide emulsion layers being spectrally sensitized with a compound represented by the following general formula (I):

wherein L₁, L₂ and L₃ each represents an unsubstituted or substituted methine group; Q represents an aryl group containing at least one sulfo or carboxyl group; R₃ and R₄ each represents -COR₅, -COOR₅,

-CN, or -CF₃; R₅ and R₆ each represents a hydrogen atom, an unsubstituted or substituted alkyl group, or an unsubstituted or substituted aryl group; m represents 0, 1, 2, or 3; n represents 0, 1, or 2; and M represents K or Na.

2. The silver halide color photographic material of Claim 1, wherein said silver halide emulsion layer spectrally sensitized by the compound of general formula (I) further contains a compound represented by the following general formula (III):

wherein D represents a divalent aromatic group; R₇, R₈, R₉ and R₁₀ each represents a hydrogen atom, a hydroxy group, an alkoxy group, an aryloxy group, a halogen atom, a heterocyclic group, a mercapto group, an alkylthio group, an arylthio group, a heterocyclic thio group, an amino group, an alkylamino group, a cyclohexylamino group, an arylamino group, a heterocyclic amino group, an aralkylamino group, or an aryl group; Y₁ and Z₃ represents -N= or -CH=, provided that at least either of them is -N=; Y₂ and Z₄ have the same meaning as Y₁ and Z₃, respectively.

3. The silver halide color photographic material of Claim 1, wherein m in said general formula (II) is 1, 2 or 3.

4. The silver halide color photographic material of Claim 1, wherein said water-soluble bromide is potassium bromide, sodium bromide or ammonium bromide.

5. The silver halide color photographic material of Claim 1, wherein said water-soluble bromide is added in an amount of from 1 × 10⁻³ to 1 × 10⁻¹ mol per mol of silver halide.

6. The silver halide color photographic material of Claim 1, wherein R₁ and R₂ in said general formula (I) each represents an unsubstituted alkyl group or a sulfoalkyl group.

7. The silver halide color photographic material of Claim 1, wherein at least one of R₁ and R₂ represents an unsubstituted alkyl group containing 5 to 8 carbon atoms.

8. The silver halide color photographic material of Claim 1, wherein V₁, V₂, V₃, V₄, V₅, V₆, V₇ and V₈ in said general formula (I) each represents a hydrogen atom, an unsubstituted alkyl group or an alkoxy group but all of V₁ to V₈ cannot be a hydrogen atom at the same time.

9. The silver halide color photographic material of Claim 1, wherein Y ≦ -0.15 in the case of Z = an oxygen atom, while Y ≦ -0.30 in the case of Z = a sulfur atom.

10. The silver halide color photographic material of Claim 1, wherein -0.90 ≦ Y ≦ -0.17 in the case of Z = an oxygen atom, while -1.05 ≦ Y ≦ -0.34 in the case of Z = a sulfur atom.

11. The silver halide color photographic material of Claim 2, wherein at least one of R₇, R₈, R₉ and R₁₀ in said general formula (III) represents an aryloxy group, a heterocyclic thio group or a heterocyclic amino group.

12. The silver halide color photographic material of Claim 1, wherein Q in said general formula (II) represents a phenyl group containing at least two sulfo groups.

13. The silver halide color photographic material of Claim 1, wherein L₁, L₂ and L₃ in said general formula (II) each represents a methine group and n represents 2.

14. The silver halide color photographic material of Claim 1, wherein the amount of the dye represented by general formula (II) in which n is 2 is from 1.2 × 10⁻⁵ mol/m² to 5 × 10⁻⁴ mol/m².

15. The silver halide color photographic material of Claim 1, wherein the amount of the dye represented by general formula (II) in which n is 2 is from 1.4 × 10⁻⁵ mol/m² to 2 × 10⁻⁴ mol/m².

16. The silver halide color photographic material of Claim 2, wherein the amount of the compound represented by general formula (III) is from 1 × 10⁻⁶ to 1 × 10⁻¹ mol per mol of silver halide.

17. The silver halide color photographic material of Claim 1, wherein said silver halide emulsion layer spectrally sensitized by the compound of general formula (I) contains silver halide grains having a halide composition containing chloride in a proportion of 90 mol% or more of the entire halides constituting the grains.

18. The silver halide color photographic material of Claim 1, wherein said silver halide emulsion layer spectrally sensitized by the compound of general formula (I) contains silver halide grains having a halide composition being chlorobromides or chlorides containing chloride in a proportion of 95 mol% or more of the entire halides constituting the grains, and not containing iodide in a substantial amount.

19. The silver halide color photographic material of Claim 18, wherein said silver halide grains have a halide composition being chlorobromides or chlorides containing chloride in a proportion of 97 mol% or more of the entire halides constituting the grains, and not containing iodide in a substantial amount.

20. The silver halide color photographic material of Claim 17, wherein said silver halide grains are monodispersed emulsions having a variation coefficient (s/d) of 0.2 or less.