JPS5810739B2 - Silver halide color photographic material - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a silver halide color photographic light-sensitive material, and particularly to a silver halide color photographic light-sensitive plate material containing a novel yellow-forming coupler.

To form a color photographic image based on the exemption method, silver halide grains of an exposed photographic emulsion are generally reduced using an aromatic-grade amine compound, particularly an N,N-disubstituted paraphenylenediamine compound, as a developing agent. However, a process is utilized in which the oxidized products of the developing agent produced at the same time react with the coupler to give cyan, magenta, and yellow dye images.

The couplers for the above color development method have a phenolic hydroxyl group, an aniline amino group, or an active methylene group, and are oxidatively coupled with an aromatic-grade amine developer to produce a dye that absorbs light in the visible wavelength range. It is a compound that gives

The yellow dye image is responsible for the absorption of blue light in the wavelength range of about 400 to 500 millimicrons.

As yellow-forming couplers, beta-ketoacetoacetic acid esters, beta-diketones, N,N-malondiamides, alpha-acylacetamides, and the like are conventionally known.

Among these, alpha acylacetamides have been widely used in the field of color photography as good yellow-forming couplers.

However, alpha acylacetamides have many drawbacks as couplers, and yellow dyes derived from them have many drawbacks as images, and have never been satisfactory.

Alpha-acylacetamides require 4 equivalents of silver halide per molecule as an oxidizing agent to convert to r-zomethine dyes, and the resulting dye is approximately 20,00010 mo
Since it has only a very thick molecular absorbance of about 1/Cm, it has been necessary to use a photographic emulsion containing a large amount of silver halide in order to obtain the absorbance for blue light required for color photography.

Incorporating a large amount of silver halide into a light-sensitive material increases the scattering of light in the emulsion, which in turn reduces the ability of the light-sensitive material to record sharp images, and further reduces the processing speed of the light-sensitive material, resulting in performance deterioration. cause

Alpha-acylacetamides that can provide more vivid yellow dye images generally have low coupling reaction activity toward oxidation products of aromatic-amino color developers;
Not only does it not provide a sufficiently high amount of coloring dye, but it also delays the development of the silver halide emulsion, making rapid development difficult.

Yellow dye images derived from alpha acylacetamides lack sufficient resistance to light and moisture and fade upon storage under harsh conditions for extended periods of time.

This was one of the causes of shortening the lifespan of color photographs.

Many inventions have been made in an attempt to improve the above drawbacks.

For example, US Pat. No. 3,265,506 proposes derivatives in which the carbonyl of the acyl group of an alpha acylacetanilide is directly bonded to the tertiary carbon atom of the alkyl group.

Derivatives of this type provide dye images having both spectral absorption properties suitable for subtractive color reproduction and excellent fastness.

However, this type of derivative generally has low oxidative coupling reaction activity and does not give a yellow image with high absorbance, and the formation of the dye is not completed in the color developing bath, requiring the action of a strong oxidizing agent in subsequent processing. There were drawbacks such as.

Furthermore, in order to compensate for these drawbacks, one of the active methylene groups
by replacing hydrogen atoms with halogen atoms such as fluorine and chlorine, or by sulfo-oxy groups as shown in U.S. Pat. No. 3,415,652,
Alternatively, attempts have been made to substitute with an acyloxy group as shown in US Pat. No. 3,447,928.

However, the substitution of these active methylene groups with releasable substituents does not increase the coupling reaction activity to a satisfactory degree or causes significant color fogging.

The couplers themselves were unsatisfactory in some respects, such as being unstable and gradually changing into a state in which color development was impossible in the light-sensitive material.

Therefore, it is an object of the present invention to provide a silver halide color photographic material that provides a yellow dye image that has spectral absorption characteristics suitable for subtractive color reproduction and excellent stability despite its low silver halide content. It is to provide.

The object of the present invention is achieved by a silver halide color photographic light-sensitive material containing an acetamide-type yellow-forming coupler represented by the general formula CI). A terocyclic group is represented, and Z is a leaving group having the following structural formula.

In the general formula (1), R1 represents an alkyl group or an alkenyl group.

The carbon atom at the alpha position is primary, secondary or tertiary.

A secondary carbon is a carbon atom that is directly bonded to two other carbon atoms, or directly bonded to one carbon atom, or bonded to one other carbon atom via an oxygen atom, and 3 A carbon atom is a carbon atom that is directly bonded to three carbon atoms, directly bonded to two carbon atoms, or bonded to another carbon atom via an oxygen atom.

The carbon atoms in the beta position of R1 or more distal to the carbonyl group may be advantageously substituted by various substituents.

The number of carbon atoms contained in R1 varies depending on the other substituents R2 and Z and the purpose of use of the coupler, but is from 1 to 32.
up to is advantageous.

Specific examples of R1 are as follows.

Methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl, n-amyl, isoamyl, tert-amyl, n-hexyl, 1-methylpentyl, 2-methylpentyl, 5-methylpentyl, neopentyl , 1,1-dimethylbutyl, n-heptyl, 1-methylhexyl, 2-)tylhexyl, 3-)
Tylhexyl, 5-methylhexyl, 1,1-dimethylhexyl, n-octyl, 2-ethylhexyl, 1,1
-dimethylhexyl, n-nonyl, isononyl, n-decyl, n-cundecyl, n-dodecyl, n-tetradecyl, n-hexadecyl, n-octadecyl, 1,1-dimethylnonyldecyl, 1,1-di-n- 7milhexyl, 1-methyl-1-nonyldecyl, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, benzyl, phenethyl, allyl, oleyl, 7,7-dimethylnorbornyl, 1-)tylcyclohexyl, p-ter
Examples include t-butylphenoxy-dimethyl-methyl, α-methoxyisopropyl, chloro-1-butyl, cinnamyl, and the like.

The aryl group represented by R2 is a phenyl group or a substituted phenyl group, and the substituents include not only the following monovalent substituents but also divalent substituents that form a condensed ring with the phenyl group.

Aryl groups with fused rings include naphthyl groups, quinolyl groups,
Examples include inquinolyl group, chromanyl group, and tetrahydronaphthyl group.

Furthermore, as a modification of the general formula I, there may be mentioned a derivative bonded to an R2 group, or two phenyl groups directly bonded to each other, or two phenyl groups bonded by a divalent substituent. represents a divalent arylene group.

The monovalent substituent located on the phenyl group of R2 can be selected from a wide range of residues.

For example, halogen atom, alkyl group, alkenyl group, alkoxy group, aryl group, allyloxy group, carbonyl group,
Examples include sulfonyl group, carboxyl group, alkoxycarbonyl group, carbamyl group, sulfamyl group, acylamide group, ureido group, sulfonamide group, amino group, nitro group, cyano group, and hydroxyl group.

The hydrogen atoms of these groups may be further substituted.

Advantageously, the phenyl group of R2 is substituted with one or more of the above-mentioned substituents.

Among them, one of the R2 positions is a halogen atom such as fluorine, chlorine, or bromine, an alkoxy group such as methoxy group, ethoxy group, propoxy group, or octoxy group, an allyloxy group such as phenoxy group, triloxy group, or an alkyl group such as methyl or ethyl group. 1. Compounds substituted with amino groups such as N,N-dimethylamino and N-n-butyl-N-n-octylamino are particularly useful in the present invention.

Furthermore, by substituting the meta-position, para-position, or both positions of the phenyl group of R2 with the above-mentioned monovalent substituents, it is possible to adapt the properties of the coupler and its dye to the intended use.

Substitution of both ortho positions of the phenyl group of R2 is not preferred because it significantly reduces the coupling activity of the coupler and deteriorates the spectral absorption characteristics of the dye.

In the heterocyclic group represented by R2, the carbon atom of the ring is a member of the conjugated electronic group of the ring.

Such heterocyclic groups include thiophene-based ones, such as 2-chenyl, 3-4enyl, 2-benzochenyl, 3-benzochenyl, 2-naphthochenyl and 3-
Such as naphthochenyl group, furan group, such as 2-furyl, 3-furyl, 2-benzofuranyl, 3-
Such as benzofuranyl, 1-inbenzofuranyl and 3-isobenzofuranyl, those of the pyran series such as 3-pyranyl, 4-pyranyl, 5-pyranyl and 6-pyranyl, those of the chromene series such as 3-pyranyl, etc. Chromenyl, as well as those such as 4-chromenyl, pyrrole, pyrazole, and pyridine, such as 2-
Pyridyl, 3-pyridyl, 4-pyridyl, 2-quinolyl, 3-quinolyl, 4-quinolyl, 1-isoquinolyl, 3
-isoquinolyl and 4=quinolyl, pyrazine series such as 2-pyrazinyl, 2-quinazolinyl, pyrimidine series such as 2-pyrimidinyl, 4-pyrimidinyl, 5-pyrimidinyl, 2-quinazolinyl and - such as quinazolinyl, pyridazines, such as 2-pyridanidyl, 3-pyridazinyl, 3-dinolinyl and 4-dinolinyl,
Indolizine series, 1-intridinyl, 2-intridinyl, 3-intridinyl, 5-indolizyl,
Such as 6-indolizil and 7-indolizil,
Perimidine type, such as 2-perimidine type, thiazole type, such as 2-thiazolyl, 2-
Such as benzothiazolyl, 3-inchazolyl, 4-inchazolyl, and 5-inchazolyl, imidazole type, such as 2-benzimidazole, oxazole type, 1,3,5-triazine type, oxazine type. Examples include things such as

These heterocyclic groups further include halogen atoms, alkyl groups, alkenyl groups, alkoxy groups, aryl groups, allyloxy groups, carbonyl groups, sulfonyl groups, carboxyl groups, alkoxycarbonyl groups, carbamyl groups, sulfone groups, sulfamyl groups, and acylamide groups. group, ureido group,
Sulfonamide group, amine group, nitro group, cyan group,
Can be substituted by hydroxyl groups.

Furthermore, as a variant of general formula I, two or two heterocyclic groups linked directly to each other, or two
Examples include derivatives bonded to two heterocyclic groups connected by a valent substituent.

Here, R2 represents a divalent heterocyclic group.

A yellow-forming coupler of the general formula I that is particularly suitable for implementing the invention is represented by the general formula below.

In the formula, Z represents the same atomic group as in the general formula (2).

X represents a halogen atom, an alkoxy group, an allyloxy group, or a tertiary amine 7 group, and Yl, Y2, and ¥3 are the same or different substituents and represent a hydrogen atom, a halogen atom, an alkyl group, an alkenyl group, or an alkoxy group.

Aryl group, allyloxy group, carbonyl group, sulfonyl group, carboxyl group, alkoxycarbonyl group, carbamyl group, sulfone group, sulfamyl group, acylamido group, ureido group, sulfonamide group, amide group, nitro group, cyan group To be elected.

The silver halide photographic emulsion used in the present invention includes silver chloride,
Photosensitive silver halides such as silver bromide, silver chlorobromide, silver iodobromide, and silver chloroiodobromide are dispersed in the form of colloidal particles in a hydrophilic polymer material, and can be prepared by various methods. be done.

Hydrophilic polymeric substances contained in photographic emulsions include proteins such as gelatin, polymeric nonelectrolytes such as polyvinyl alcohol, polyvinylpyrrolidone, and polyvinyl acrylamide, polyacrylamide treated by Huffmann decomposition reaction, acrylic acid and vinyl Polymeric ampholytes such as imidazole copolymers are suitable.

Silver halide photographic emulsions also contain photographically useful components such as sensitizers, stabilizers, hardeners, and surfactants.

The couplers used in this invention must be immobilized in the emulsion layer.

That is, it must be made diffusion resistant.

Otherwise, the coupler will move through the light-sensitive material and develop color in an emulsion of incorrect color sensitivity, significantly impairing the color reproduction ability of the light-sensitive material.

In order to make the coupler resistant to diffusion, a group containing a hydrophobic residue having 8 to 32 carbon atoms is introduced into the coupler molecule.

Such residues are called ballast groups.

The ballast group is connected to the coupler bone structure directly or via an amine bond, ether bond, thioether bond, carbonamide bond, sulfonamide bond, urea bond, ester bond, imide bond, carbonyl bond, sulfonyl bond, etc.

Specific examples of the ballast group are as follows.

(1) Alkyl and alkenyl groups (11) Alkoxyalkyl groups, such as those described in Japanese Patent Publication No. 39-27563 (iii) Alkylaryl groups, such as (IV) Alkylaryloxyalkyl groups, such as (V) Acylamide alkyl groups, e.g., U.S. Pat. Nos. 3,337,344 and 3,418
(vi) Alkoxyaryl and allyloxyaryl groups as described in No. 129, for example, (Vii) A long-chain aliphatic group of alkyl or alkenyl and a carboxyl group are combined with a water-solubilizing group of sulfo. The oil-soluble diffusion-resistant coupler used in the invention is once dissolved in an organic solvent and then dispersed into fine colloidal particles in a photographic emulsion and incorporated into a photographic material.

A specific example of a method for dispersing couplers suitable for carrying out the present invention is described in detail in Japanese Patent Publication No. 48-32727.

The organic solvent used to dissolve the coupler is poorly soluble in water and has a high boiling point, and the substances that coexist with the coupler in color photosensitive materials include substituted hydrocarbons, carboxylic acid esters, and carboxylic acid amides. There are compounds such as , phosphoric acid esters, and ethers, and specific examples include G-n.
-Butyl phthalate, di-isooctyl azelate, di-n-butyl sebacate, tricresyl phosphate, tri-n-hexyl phosphate, N,N-diethyl caprylamide, butyl-m-pentadecyl phenyl ether, chlorinated There is paraffin.

In addition to these high-boiling solvents, it is advantageous to use auxiliary solvents which can be removed during the production of the light-sensitive material to aid in the dissolution of the coupler.

Examples of this include glopylene carbonate, ethyl acetate,
Examples include butyl acetate, cyclohexanol, tetrahydrofuran, and cyclohexanone.

It is advantageous to use surfactants to help finely disperse these oil-soluble couplers in the hydrophilic polymeric materials used in photographic emulsions.

In particular, anionic surfactants such as sodium cetyl sulfate, sodium p-dodecylbenzenesulfonate, sodium nonylnafucrenesulfonate, di(2-ethylhexyl)-α-sulfosuccinate sodium salt, and sorbitan sesquioleic acid. Nonionic surfactants such as esters and sorbitan monolaurates are suitable.

An emulsifying homogenizer is used to disperse oil-soluble couplers.
Colloid mills, ultrasonic emulsifiers, etc. are useful.

A diffusion-resistant coupler represented by the general formula I and having a ballast group and a carboxylic acid group or a sulfonic acid group in one molecule is soluble in neutral to weakly alkaline aqueous solutions.

Couplers can be incorporated into photographic emulsions by adding their aqueous solutions to the photographic emulsion.

It is believed that couplers become diffusion resistant by forming micelles (1) within hydrophilic polymers.

Specific examples of the yellow-forming coupler used in the silver halide color photographic material of the present invention are shown below, but the invention is not limited thereto.

The amount of the coupler used in the present invention varies depending on the light-sensitive material used and the type of development process, but the molar ratio of the coupler to the silver halide in the emulsion ranges from 0.02 to 1.0.
Particularly useful is a range of amounts added up to .

If the amount added is less than this lower limit, a large amount of silver halide is required to provide the coloring absorbance required for the light-sensitive material, and as a result, light scattering in the emulsion layer increases, reducing the sharpness of the image. An increase in the emulsion layer increases the thickness of the emulsion layer, impairing the speed of the development process.

If the amount added is greater than the above upper limit, the conversion of the coupler used into the dye will be insufficient, resulting in a decrease in coupler utilization efficiency, which is not only economically disadvantageous, but also increases the thickness of the emulsion layer. As can be seen, the advantages to be obtained by the present invention cannot be fully achieved outside the above-mentioned addition amount range.

In carrying out the present invention, couplers represented by formula I may be used alone or in combination of two or more.

Furthermore, it may be used in combination with couplers other than those represented by general formula (2).

The couplers used in the present invention are α-(aliphatic acyl)
One hydrogen atom on the α-position carbon atom of acetamide is N
- It is characterized by being substituted with a cyclic carboimide group.

That is, the nitrogen atom activated by two carbonyl groups is bonded to the α-position carbon atom of the acylacetamide.

It is devised that the oxidation product of the aromatic primary amine developer reacts with the α-carboimide acyl acetamide compound, and the bond between the imide nitrogen atom and the α-position carbon atom is broken to generate an azomethine dye and an imide ion. be done.

In contrast, the conventional α-1-position substituent of acylacetanilide was bonded to the α-position carbon atom through a halogen atom, an oxygen atom, or a sulfur atom.

The imide-substituted couplers of the present invention are thus distinguished from conventional ones in the mode of binding.

The α-imidoacylacetamide type couplers used in the present invention exhibit the following valuable characteristics.

The α-imidoacylacetamide type coupler of the present invention has 2
It is an equivalent coupler.

That is, to produce one molecule of dye, only two equivalents of silver halide are required as an oxidizing agent.

It requires only half the amount of silver halide compared to the conventionally widely used 4-equivalent acylacetamide type coupler, thus reducing the amount of silver halide contained in the photosensitive material, which in turn can reduce the manufacturing cost of the photosensitive material. Alternatively, the sharpness of the image can be improved by reducing light scattering by emulsion grains, and the emulsion layer can be made thinner, making it possible to shorten the development process.

The imide coupler used in the present invention has high coupling reaction activity against oxidation products of aromatic primary amine developers, and therefore can rapidly remove oxidation products of developing agents that occur during color development. , which accelerates the development of silver halide emulsions.

In this way, the formation of the dye image of the present invention is accomplished in a short period of time.

Due to the high reaction activity of this coupler, sufficient color development can be obtained even if the amount of solvent used to disperse the oil-soluble coupler, especially non-volatile solvent, is greatly reduced.

By reducing the amount of solvent remaining in the light-sensitive material in this way, it has become possible to improve the mechanical strength of the emulsion layer.

The imido-substituted acylacetanilide type couplers used in this invention require the dye formation process to be completed in a color developing bath, followed by the use of a bleach bath containing a strong oxidizing agent such as red blood salt or potassium dichromate. I don't.

On the other hand, most of the acylacetamide type couplers whose coupling reaction sites are not substituted, especially almost all of the unsubstituted couplers in which the imide group of general formula (2) is replaced with a hydrogen atom, develop color in a color developing bath. Since the reaction was not completed, a considerable portion of the coupling reaction product remained in the colorless leuco state, and the above-mentioned oxidizing agent was required to completely develop the color.

The dye images derived from the imido-substituted acylacetamide type couplers used in this invention have very little tendency to fade even when stored under harsh conditions for long periods of time.

In particular, dye images formed from couplers represented by the general formula (2) are stable and less susceptible to light and moisture, making it easy to preserve color photographic images over long periods of time.

The silver image produced as a by-product in the process of forming a dye image using the light-sensitive material of the present invention is easily oxidized during the bleaching process, and the developed silver can be completely removed during a short processing time.
A clear yellow dye image is obtained that is not contaminated by residual silver.

The imide group-substituted acylacetamide type coupler used in the present invention can be synthesized in high yield using industrially easily available raw materials.

Furthermore, by appropriately selecting Z in the general formula, the properties of the coupler, especially the coupling reaction activity, can be adjusted freely depending on the purpose of use of the light-sensitive material.Changes in the acylacetamide core structure can improve not only the reaction activity but also the dye image. Since the scope of change is limited because it also changes the spectral absorption characteristics, the adjustment by Z is of great significance.

The couplers used in the invention and the dye images obtained therefrom are particularly advantageous in that they combine the features individually listed above.

The yellow-forming coupler used in the present invention is generally synthesized by reacting a halogenated form of the corresponding mother coupler with a corresponding imide in the presence of a base such as triethylamine.

A specific synthesis example is shown below.

Synthesis example 1 α-pivalyl α-(3-uracilyl)-5-[γ-
Synthesis of (2,4-di-t-amylphenoxy)-butyramide]-2-chloroacetonylide [coupler (2)] 15 g of α-pivalyl α-chloro5-[γ-(2,
10 of 4-di-tert-amylphenoxybutyramide]-2-chloroacetanilide and 3I clasil
Dissolved in 0 cc of acetonitrile.

2.5 g of triethylamine was added to this solution, and the mixture was heated under reflux for 8 hours.

Acetonitrile was distilled off under reduced pressure.

The residue was dissolved in 50 cc of acetic acid, and this solution was added dropwise to 11 ml of water with stirring.

The precipitated crystals were recrystallized using ethyl acetate, and 5 g
I got the desired coupler.

The melting point is 189-190°C, and the result of elemental analysis is C: 65.
05%, H near, 17%, N: 8.10% (C3□H4
The calculated value for 9CIN406 is C: 65.25 Chu, H
N: 20%, N: 8.23%).

Synthesis Example 2 α-pivalyl α-(5,5-dimethyl-2゜4-dioxo-3-oxazolidinyl)-5-[γ-(2,4-
Synthesis of di-t-amylphenoxy)butyramide-2-chloroacetanilide [coupler (5)]
4-di-t-amylphenoxy)butyramide sea 2-
Chloroacetanilide and 5.5 g of 5,5-dimethyl-
100cc of 1,3-oxazolidine-2゜4-dione
Dissolved in acetonitrile.

To this solution was added 4.39 g of triethylamine and heated under reflux for 2 hours.

The reaction solution was poured into water, extracted with ethyl acetate, and then the solvent was distilled off.

Recrystallization from methanol yielded 13.5 g of the desired coupler.

The melting point is 165-166°C, and the result of elemental analysis is C: 65.
30%, H near, 48%, N: 5.99% (C38H5
The calculated value for 2ClN30□ is C: 65.36, H
N: 51%, N: 6.02%).

Synthesis example 3 α-pivalyl α-(5-ethyl-2,4-dioxo-
3-thiazolidinyl)-5-(γ-(2,4-dyl t-
Synthesis of 2-chloroacetanilide (amylphenoxy)butyramide [coupler (6)] 13 g of α-pivalyl α-chloro
4-di-t-amylphenoxybutyramide]-2-
Chloroacetanilide and 6.2 g of 5-ethyl-1,3
-thiazolidine-2,4-dione was dissolved in 100 cc of acetonate.

4.3 g of triethylamine was added to this solution and heated under reflux for 2 hours.

The reaction solution was poured into water, extracted with ethyl acetate, and then the solvent was distilled off.

Recrystallization was carried out using a rig to obtain 14 g of the desired coupler.

The melting point is 163-165°C, and the result of elemental analysis is C:63.
90%, H near, 24%, N: 5.79% (C738H
The calculated value for 62ClN306S is C: 63.89%
, H near, 34th section, N: 5.88%).

A yellow image is formed when a silver halide photographic light-sensitive material containing the yellow-forming coupler of the present invention is processed with a developer containing an aromatic-grade amine developer after imagewise exposure.

The aromatic-grade amine developers used include compounds having a primary amine group on the aromatic ring and capable of developing exposed silver halide, or precursors for forming such compounds.

Among these, ortho-aminophenol, para-aminophenol, N,N-disubstituted-ortho-phenylenediamine, and especially N,N-paraphenylenediamine are useful.

Specific examples include 4-amino-3-dimethylamino-N, N-diethylaniline, 4-amine-3-ethoxy-N, N-diethylaniline, 4-amino-3,5-
Dimethyl-N, N-diethylaniline, 4-amino-3
-Methyl-N=ethyl-N-(β-hydroxyethyl)
Aniline, 4-amino-3-methyl-N, N-diethylaniline 4-j'mino-3-methyl-N-ethyl-N-
(β-methylsulfonamidoethyl)aniline, 4-
Amine-3-(β-methylsulfonamidoethyl)-
N,N-diethylaniline, 4-amino-N-ethyl-
Examples include N-(β-hydroxylethyl)aniline, 4-amino-N,N-diethylaniline, and 4-amino-N-ethyl-N-ω-sulfobutylaniline.

In addition to these developers, the developer solution may contain conventional developer additives such as alkalizing agents, antioxidants, antifoggants, and the like.

The present invention will be explained in more detail with reference to Examples below.
The present invention is not limited only to these examples.

Example 1 5x10-3 mol of the coupler (1) substituted by carbonimide groups according to the invention, 4.5 ml of di-n-j thyl fucurate, 8 ml of cyclohexanone and bis-(2-
ethylhexyl)-α-sulfosuccinate (Na salt)
A solution obtained by heating and dissolving 0.2 g on a heat plate was added to 60 ml of an aqueous solution containing 5 g of gelatin.
The coupler was finely dispersed by applying vigorous mechanical agitation in the homoblended solution.

The entire amount of this coupler dispersion was added to 150 g of a fine grain emulsion containing 3.8 g of silver bromide and 13 g of gelatin.
A photographic film was prepared by coating a cellulose triacetate film to a dry film thickness of 7 microns.

After exposure, these photographic films were subjected to the following treatments in sequence.

The composition of the color developer used in this process was as follows.

Color Developer A The fixing solution was an acidic aqueous solution containing sodium thiosulfate and sodium sulfite, and the bleaching solution was a neutral solution containing potassium ferricyanide and potassium bromide.

The spectral absorption characteristics of the obtained yellow dye image were measured using a spectrophotometer, and a maximum polarization value of 450 millimicrons was obtained, indicating that the yellow dye image had spectral absorption characteristics suitable for subtractive color reproduction.

Example 2 The above coupler (5), α-pivalyl α-(5°5-
dimethyl-2,4-dioxo-3-oxazolidinyl)
-2-Chloro-5-[γ-(2,4-di-tert-amylphenoxy)butyramide]acetanilide 52.
4 g of di-n-butyl phthalate and 105 ml of ethyl acetate were heated to 50°C, and a solution obtained was mixed with 50 g of gelatin and 2.5 g of di-(2-ethylhexyl)-α-sulfonic acid trichum. 500ml of aqueous solution containing
After stirring, vigorous mechanical stirring was applied to finely emulsify and disperse the coupler with the solvent.

The entire amount of this emulsified dispersion was added to 1.0 kg of a photographic emulsion containing 0.30 mol of silver bromide and 60 g of gelatin, and 2-hydroxy-4,6-dichloro-8-triazine sodium salt was added as a hardening agent. Add 22 ml of 4% aqueous solution, p
After adjusting to H6.0, it was coated on a cellulose triacetate film base so that the coated silver amount was 0,751/m2.

This is designated as sample A.

This sample A contained 1.75.times.10@-3 moles/m' of coupler.

In addition, the coupler (6), α-pivalyl α-(5
-ethyl-2,4-dioxo-3-thiazolidinyl)-
2-Chloro-5-[γ-(2,4-di-tert-amylphenoxy)butylamitoacedoa; Lido 53.5
Sample B was prepared by the same method as sample A was prepared using g.

This sample B contained 1.77.times.10@-3 moles/m@2 of coupler.

As a comparative sample, coupler (a
), α-pivaluru2-chloro5-[α-(2,4-
21.5 g of di-tert-amylphenoxy)butyramide]acetanilide and coupler (b), α-pivalyl-2-chloro5-[γ-(24-di-tert-amylphenoxy)butyramide]acetanilide 21.
5g of di-n-butyl phthalate 22
ml and 43 ml of ethyl acetate were added and heated to 50°C. The resulting solution was mixed with 21 gelatin and 1. After adding it to 200rd aqueous solution containing Qg and stirring, vigorous mechanical stirring was applied to finely emulsify and disperse the coupler together with the solvent.

The total amount of these emulsions was prepared using the same photographic emulsion as when preparing sample A, adding 16 ml of the same hardener, and adjusting the pH to 6.
, O, and then coated on a cellulose triacetate film base in the same manner so that the coated silver amount was 1.50 g/m2.

These are designated as samples C and D.

These samples C and D each have 1.78X10-3 mol/
m2 and 1.77X10-3 moles/m2 of coupler.

After stepwise exposure for sensitometry was applied to these prepared samples A to D, the following treatment was performed, and the treatment solution had the following composition.

After the treatment, the optical density against blue light was measured for each of these samples A to D, and the results shown in Table 2 below were obtained.

Both of the obtained color images had a maximum absorption at 449 mμ, and were clear yellow pigments with no reddish tint.

Next, for samples A to D, the maximum density for blue light obtained when the color development processing time was changed was measured, and the results shown in Table 3 were obtained.

As a result, the couplers of the present invention have a high silver content even though the amount of silver is reduced to 1/2 compared to couplers (a) and (b) used in comparative samples that are not substituted at the active site. It is possible to provide sensitivity, gradation, and color density, and furthermore, it is possible to provide sufficient color development with a short color development process, so that processing time can be shortened.

Furthermore, the fact that it shows high color development even when a small amount of silver halide is used as compared to an active position unsubstituted coupler indicates that it has the possibility of reducing the thickness of the emulsion layer.

Claims (1)

[Scope of Claims] 1. A silver halide color photographic material containing a diffusion-resistant acetamide-type yellow-forming coupler represented by the following general formula (I). In the formula, R1 represents an alkyl group or an alkenyl group, R2 represents an aryl group or a heterocyclic group, and Z represents a leaving group having the following structural formula.