JP2811229B2 - New photographic coupler - Google Patents

Description

Description: FIELD OF THE INVENTION The present invention relates to a novel photographic coupler used as a color photographic material, and more specifically, to form a dye image having excellent heat, humidity and light fastness. Related to photographic couplers.

BACKGROUND OF THE INVENTION After a silver halide photographic light-sensitive material is exposed to light and then subjected to color development, the oxidized aromatic primary amine color developing agent reacts with a dye-forming coupler in the exposed area. Dyes are formed and a color image is formed.

Generally, in this photographic method, a color reproduction method based on a subtractive color method is used, and yellow, magenta, and cyan color images are formed.

Examples of the photographic coupler used for forming the yellow image include an acylacetanilide-based coupler, and examples of the magenta image-forming coupler include pyrazolone, pyrazorobenzimidazole, and pyrazolotriazole. Alternatively, indazolone couplers are known, and as a coupler for forming a cyan image, for example, a phenol or naphthol coupler is generally used.

It is desired that the dye image thus obtained does not discolor even if it is exposed to light for a long time or stored under high temperature and high humidity.

However, phenol-based couplers and naphthol-based couplers, which have been studied as couplers for forming cyan dyes, are characterized by the spectral absorption characteristics of the formed cyan dye image, heat resistance, moisture resistance and light resistance. Various proposals have been made to achieve this improvement, including devising a substituent, but a compound satisfying all of these has not yet been obtained.

Therefore, the present inventors have further studied the above point, and as a result, have found a photographic coupler capable of forming a cyan dye image which does not cause a hue change with respect to heat, humidity and light, and have developed the present invention. It was completed.

[Object of the Invention] A first object of the present invention is to provide a novel photographic coupler used as a material for color photographic.

A second object of the present invention is to provide a photographic coupler which forms a cyan dye image which does not change in hue to heat, humidity and light.

[Constitution of the Invention] The above object of the present invention is achieved by a photographic coupler represented by the general formula [I] (hereinafter, referred to as the coupler of the present invention).

[Wherein R ₁ , R ₂ , R ₃ and Y represent a hydrogen atom or a substituent, and R ₂ and R ₃ may combine to form a ring.

X represents a hydrogen atom or a substituent which is eliminated by reaction with an oxidized form of a color developing agent. Hereinafter, the present invention will be described more specifically.

In the general formula [I], R ₁ , R ₂ , R ₃ and Y represent a hydrogen atom or a substituent, and the substituents represented by R ₁ , R ₂ and R ₃ are not particularly limited, but may be representative. Has an alkyl,
Aryl, anilino, acylamino, sulfonamide,
Examples of each group include alkylthio, arylthio, alkenyl, and cycloalkyl.In addition, halogen atoms and cycloalkenyl, alkynyl, heterocycle, sulfonyl, sulfinyl, phosphonyl, acyl, carbamoyl, sulfamoyl, cyano, alkoxy, sulfonyloxy, Aryloxy, heterocyclic oxy, siloxy, acyloxy, carbomoyloxy, amino, alkylamino, imide, ureido, sulfamoylamino, alkoxycarbonylamino, aryloxycarbonylamino, alkoxycarbonyl, aryloxycarbonyl, multiple-ring thio, thioureido Carboxy, hydroxy, mercapto, nitro, sulfo, etc .; spiro compound residues; bridged hydrocarbon compound residues.

Among the substituents represented by R ₁ , R ₂ and R ₃ , the alkyl group preferably has 1 to 32 carbon atoms and may be linear or branched.

 As the aryl group, a phenyl group is preferable.

Examples of the acylamino group include an alkylcarbonylamino group and an arylcarbonylamino group.

Examples of the sulfonamide group include an alkylsulfonylamino group and an arylsulfonylamino group.

The alkyl component and the aryl component in the alkylthio group and the arylthio group include the above-described alkyl groups and aryl groups.

The alkenyl group is preferably a group having 2 to 32 carbon atoms, and the cycloalkyl group is preferably a group having 3 to 12 carbon atoms, particularly 5 to 7 carbon atoms. The alkenyl group may be linear or branched.

Examples of the cycloalkenyl group include those having 3 to 12 carbon atoms, particularly 5 carbon atoms.
To 7 are preferred.

As a sulfonyl group, an alkylsulfonyl group, an arylsulfonyl group, etc .; As a sulfinyl group, an alkylsulfinyl group, an arylsulfinyl group, etc .; As a phosphonyl group, an alkylphosphonyl group, an alkoxyphosphonyl group, an aryloxyphosphonyl group, an arylphosphonyl group As an acyl group, an alkylcarbonyl group, an arylcarbonyl group, etc .; As a carbamoyl group, an alkylcarbamoyl group, an arylcarbamoyl group, etc .; As a sulfamoyl group, an alkylsulfamoyl group, an arylsulfamoyl group, etc .; As an acyloxy group, an alkyl group Carbonyloxy group, arylcarbonyloxy group, etc .; carbamoyloxy group includes alkylcarbamoyloxy group, arylcarbamoyloxy group, etc .; A luureido group, an arylureido group, or the like; a sulfamoylamino group such as an alkylsulfamoylamino group or an arylsulfamoylamino group; a restored ring group preferably having 5 to 7 members; -Furyl group, 2-thienyl group, 2-pyrimidinyl group, 2-benzothiazolyl group, 1-pyrrolyl group, 1-tetrazolyl group and the like; As the heterocyclic oxy group, those having a 5- to 7-membered heterocyclic ring are preferable. 3,4,5,6-tetrahydropyranyl-2-oxy group, 1-phenyltetrazol-5-oxy group, etc .; As the heterocyclic thio group, a 5- to 7-membered heterocyclic thio group is preferable, for example, 2-pyridylthio. Group, 2-benzothiazolylthio group, 2,4-diphenoxy-1,3,5-triazole-
6-thio group and the like; siloxy group as trimethylsiloxy group, triethylsiloxy group, dimethylbutylsiloxy group and the like; imide group as succinimide group, 3-heptadecylsuccinimide group, phthalimide group, glutarimide group; Spiro compound residues include spiro [3.3] heptane-
1-yl and the like; bicyclo [2.2.1] as a bridged hydrocarbon compound residue
Heptane-1-yl, tricyclo [3.3.1.1 ^3,7 ] decan-1-yl, 7,7-dimethyl-bicyclo [2.2.1] heptan-1-yl and the like.

As R ₂ and R ₃ , among the substituents, for example, an alkyl group, an aryl group, a carboxyl group, an oxycarboxyl group, a cyano group, a hydroxy group, an alkoxy group, an aryloxy group, an amino group, an amide group and a sulfone Each group such as an amide group and the like, a hydrogen atom, a halogen atom and the like are preferable.

R ₂ and R ₃ may combine to form a ring, and the ring is preferably a saturated or unsaturated 5-, 7-, or 8-membered ring. And a quinoline ring.

The above group may further have a substituent such as a non-diffusible group such as a long-chain hydrocarbon group or a polymer residue.

Examples of the group capable of leaving by reaction with the oxidized form of the color developing agent represented by X include, for example, a halogen atom (a chlorine atom,
Bromine atom, fluorine atom, etc.) and alkoxy, aryloxy, heterocyclic oxy, acyloxy, sulfonyloxy,
Alkoxycarbonyloxy, aryloxycarbonyl, alkyloxalyloxy, alkoxyoxalyloxy, alkylthio, arylthio, heterocyclic thio, alkyloxythiocarbonylthio, acylamino, sulfonamide, nitrogen-containing heterocyclic ring linked by N atom, alkyloxycarbonyl Amino, aryloxycarbonylamino, carboxyl, (R ₁ ′, R ₂ ′, R ₃ ′ and Y ′ are R ₁ , R ₂ R ₃ and Y
And Ra and Rb each represent a hydrogen atom, an aryl group, an alkyl group or a heterocyclic group. And the like, and preferably a halogen atom. Among these, those particularly preferred as those represented by X are a hydrogen atom and a chlorine atom.

In the general formula [I], Y represents a hydrogen atom or a substituent. Preferred substituents represented by Y are, for example, those in which the compound of the present invention is released from the compound after reacting with the oxidized form of the developing agent However, for example, the substituent represented by Y is a group capable of leaving under an aliasing condition as described in JP-A-61-228444 and the like, and is described in JP-A-56-133374 and the like. Substituents that are coupled / off by the reaction with the oxidized developing agent as described above.
Preferably Y is a hydrogen atom.

Therefore, the compound of the present invention represented by the general formula [I] is
More preferably, it is represented by the general formula [II].

[Wherein, R ₁ , R ₂ , R ₃ and X have the same meanings as R ₁ , R ₂ , R ₃ and X of the compound represented by the general formula [I]. Next, typical examples of the compound of the present invention are shown below, but the present invention is not limited thereto.

The coupler of the present invention is described in Journal. of. Organic. Chemistry (J.Org.Chem.), 1959, 24th
Vol., Pages 779 to 787, and can be easily synthesized according to the described synthesis method.

In addition, the above cited document does not describe at all that the compounds described in the document are useful as couplers for color photography.

Synthesis Example (Synthesis of Exemplified Compound 1) 13.2 g (0.1 mol) of 2-aminoimidazole 1/2 sulfate
And 14.3 g (0.11 mol) of ethyl acetoacetate are added to 60 ml of acetic acid, and the mixture is reacted under boiling reflux for 5 hours. After the completion of the reaction, 60 ml of water
In addition, the precipitated crystals are collected by filtration and further recrystallized with water to obtain 10.7 g (yield: 72%) of the target Exemplified Compound 1. Melting point 239 ° C The structure was confirmed by NMR, IR and MASS.

The coupler of the present invention is generally used in an amount of 1 per mol of silver halide.
× 10 ^-3 mol to 1 mol, preferably 1 × 10 ^-2 mol to 8 × 10
It can be used in the range of ^-1 mol.

Further, the coupler of the present invention can be used in combination with another type of cyan coupler.

The methods and techniques used in conventional dye-forming couplers are similarly applied to the couplers of the present invention.

The coupler of the present invention can be used as a material for forming a coupler photograph by any color forming method, and specific examples thereof include an external color forming method and an internal color forming method. When used as an external color developing method, the coupler of the present invention can be used by dissolving it in an aqueous alkali solution or an organic solvent (eg, alcohol) and adding it to a developing solution.

When the coupler of the present invention is used as a material for forming a color photograph by an internal color developing method, the coupler of the present invention is used by being contained in a photographic light-sensitive material.

Typically, a method in which the coupler of the present invention is blended with a silver halide emulsion and the emulsion is coated on a support to form a color photographic material is preferably used. The coupler of the present invention is used, for example, for color photographic light-sensitive materials such as color negative and positive films and color photographic paper.

The light-sensitive material using the coupler of the present invention such as the color photographic paper may be of a single color or a multicolor. In a multicolor light-sensitive material, the coupler of the present invention may be contained in any layer, but is usually contained in a red-sensitive silver halide emulsion layer. The multicolor light-sensitive material has a dye image-forming constituent unit having photosensitivity in each of three primary color regions of the spectrum. Each structural unit can be composed of a single layer or multiple emulsion layers sensitive to certain regions of the spectrum. The constituent layers of the light-sensitive material, including the layers of the image forming constituent units, can be arranged in various orders as known in the art. A typical multicolor light-sensitive material is a cyan dye image-forming constitutional unit (at least one of cyan couplers) comprising at least one red-sensitive silver halide emulsion layer containing at least one cyan coupler.
One is the cyan coupler of the present invention. ), At least one
Magenta dye image forming unit comprising at least one green-sensitive silver halide emulsion layer containing two magenta couplers, yellow dye image comprising at least one blue-sensitive silver halide emulsion layer containing at least one yellow coupler It consists of a structural unit carried on a support.

The light-sensitive material can have additional layers such as a filter layer, an intermediate layer, a protective layer, an undercoat layer, and the like.

The coupler of the present invention may be incorporated into an emulsion according to a conventionally known method. For example, tricresyl phosphate, dibutyl phthalate or the like, a high boiling point organic solvent having a boiling point of 175 ° C. or more or a low boiling point solvent such as butyl acetate or butyl propionate alone or, if necessary, a mixture thereof may be used as a coupler of the present invention. Can be dissolved alone or in combination, mixed with an aqueous solution of gelatin containing a surfactant, and then emulsified by a high-speed rotary mixer or a colloid mill, and then added to a silver halide emulsion and contained. .

The silver halide composition preferably used in the light-sensitive material using the coupler of the present invention includes silver chloride, silver chlorobromide or silver chloroiodobromide. Further, a combination mixture such as a mixture of silver chloride and silver bromide may be used. That is, when a silver halide emulsion is used for color photographic paper, particularly fast developability is required, so that the halogen composition of the silver halide preferably contains a chlorine atom, and at least 1
% Silver chloride, silver chlorobromide or silver chloroiodobromide.

The silver halide emulsion is chemically sensitized by a conventional method. Further, it can be optically sensitized to a desired wavelength range.

Silver halide emulsions are known as antifoggants or stabilizers in the photographic industry for the purpose of preventing fogging during the production process, storage, or photographic processing of light-sensitive materials, and / or stably maintaining photographic performance. Can be added.

In the color light-sensitive material using the coupler of the present invention, a color fogging inhibitor, a dye image stabilizer, an ultraviolet light inhibitor, an antistatic agent, a matting agent, a surfactant and the like which are usually used for the light-sensitive material can be used. .

These are described in, for example, Research Disclosure, Vol. 176, pp. 22-31 (1978
December) can be referred to.

The color photographic light-sensitive material using the coupler of the present invention can form an image by performing a color development phenomenon treatment known in the art.

The color photographic light-sensitive material using the coupler of the present invention may contain a color developing agent in the hydrophilic colloid layer as the color developing agent itself or as a precursor thereof, and may be processed by an alkaline activation bath.

The color photographic light-sensitive material using the coupler of the present invention is subjected to a bleaching process and a fixing process after a color development phenomenon. The bleaching process may be performed simultaneously with the fixing process.

After the fixing process, a washing process is usually performed. Further, a stabilization treatment may be performed as an alternative to the water washing treatment, or both may be used in combination.

[Examples] Next, the present invention will be described specifically with reference to examples, but the present invention is not limited thereto.

Example 1 On a paper support laminated on both sides with polyethylene, the following layers were sequentially applied from the support side to prepare a red photosensitive color photosensitive material sample 1. The amount of the compound added is represented per 1 m ² unless otherwise specified (silver halide is a value in terms of silver).

First layer: Emulsion layer A red-sensitive emulsion comprising 1.2 g of gelatin, 0.30 g of a red-sensitive silver chlorobromide emulsion (containing 96 mol% of silver chloride) and 9.1 × 10 ^-4 mol of a comparative cyan coupler dissolved in 1.35 g of dioctyl phosphate. layer.

Second layer: protective layer A protective layer containing 0.50 g of gelatin. In addition, 2,4-
Dichloro-6-hydroxy-s-triazine sodium salt was added at 0.017 g / g of gelatin.

Next, Samples 2 to 8 of the present invention were produced in exactly the same manner as in Sample 1 except that Comparative Coupler a was replaced with a coupler shown in Table 1 (the amount added was the same molar amount as Comparative Coupler a).

To each sample, an activator and anti-biotic (a mixture of 2-methylisothiazol-3-one and 5-chloro-2-methylisothiazol-3-one) were added.

Each of the samples 1 to 8 obtained above was subjected to a wedge exposure according to a conventional method, and then subjected to a development process in the following step.

[Development process] Color development 38 ° C 3 minutes 30 seconds Bleaching and fixing 38 ° C 1 minute 30 seconds Stabilization process 25 ° C to 30 ° C 3 minutes Drying 75 ° C to 80 ° C 2 minutes Processing solution composition used in each process step is as follows. It is as follows.

[Color developing solution] benzyl alcohol 15 ml ethylene glycol 15 ml potassium sulfite 2.0 g potassium bromide 0.7 g sodium chloride 0.2 g potassium carbonate 30.0 g hydroxylamine sulfate 3.0 g polyphosphoric acid (TPPS) 2.5 g 3-methyl-4-amino-N -Ethyl-N- (β-methanesulfonamidoethyl) aniline sulfate 5.5 g Fluorescent whitening agent (4,4'-diaminostilbenzylsulfonic acid derivative) 1.0 g Potassium hydroxide 2.0 g Add water to make the total amount 1 Adjust to pH 10.20.

[Bleaching and fixing solution] Ethylenediaminetetraacetic acid ferric ammonium dihydrate 60g Ethylenediaminetetraacetic acid 3g Ammonium thiosulfate (70% solution) 100ml Ammonium sulfite (40% solution) 27.5ml Adjust the pH to 7.1 with potassium carbonate or glacial acetic acid. Add water to bring the total volume to 1.

[Stabilizing solution] 5-chloro-2-methyl-4-isothiazoline-3-
ON 1.0g Ethylene glycol 10g Add water to make 1

The concentration of each of the processed samples 1 to 8 was measured using a densitometer (model KD-7 manufactured by Konica Corporation), and each of the processed samples was subjected to high temperature and high humidity (60 ° C., 80% RH). ) The sample was allowed to stand in an atmosphere for 14 days, and the heat resistance and humidity resistance of the dye image were examined.

After irradiating each sample with a xenon fade meter for 10 days, the concentration was measured to examine the light resistance. The results are shown in Table 1. However, the heat resistance, humidity resistance and light resistance of the dye image are represented by the percentage of the dye remaining after the heat resistance, humidity resistance and light resistance sample with respect to the initial density of 1.0.

As is evident from the results in Table 1, the sample using the coupler of the present invention, compared to the sample using the comparative coupler,
It can be seen that all of them have a high dye residual ratio, are excellent in heat resistance and moisture resistance, and are robust. Further, it can be seen that the light resistance is equal to or higher than that and is excellent.

Example 2 On a subbed triacetate film, the following layers were sequentially applied from the support side to prepare a red photosensitive color photosensitive material (sample 9). The amount of the compound added is represented per 1 m ² unless otherwise specified (silver halide is a value in terms of silver).

First layer: emulsion layer 1.4 g of gelatin, red-sensitive silver iodobromide emulsion (4 mol% of silver iodide)
A red-sensitive emulsion layer consisting of 8.0 × 10 ^-4 mol of a comparative cyan coupler dissolved in 1.5 g and 1.1 g of tricresyl phosphate.

Second layer: protective layer A protective layer containing 1.5 g of gelatin. In addition, 2,4-
Dichloro-6-hydroxy-s-triazine sodium salt was added in an amount of 0.017 g / g of gelatin.

Next, in Sample 9, the comparative cyan coupler b is shown in Table 1.
Sample 10 of the present invention was prepared in exactly the same manner except that the coupler shown in FIG. 2 was used (the amount added was the same molar amount as that of the comparative coupler b).
~ 16 were prepared.

To each sample, an activator and anti-biotic (a mixture of 2-methylisothiazol-3-one and 5-chloro-2-methylisothiazol-3-one) were added.

The obtained film sample was subjected to wedge exposure by a usual method, and color development was performed in accordance with the following color processing steps.

[Processing process] (Processing temperature 38 ° C) Processing time Color development 3 minutes 15 seconds Bleaching 6 minutes 30 seconds Rinse 3 minutes 15 seconds Fixing 6 minutes 30 seconds Rinse 3 minutes 15 seconds Stabilization 1 minute 30 seconds Drying The composition of the processing solution used in each processing step is as follows.

[Color developing solution] 4-amino-3-methyl-N-ethyl-N- (β-hydroxyethyl) aniline sulfate 4.75 g anhydrous sodium sulfite 4.25 g hydroxyamine 1/2 sulfate 2.0 g anhydrous potassium carbonate 37.5 g odor Sodium chloride 1.3 g Nitrilotriacetic acid trisodium (monohydrate) 2.5 g Potassium hydroxide 1.0 g Add water to make 1 and adjust to pH 1 with sodium hydroxide
Adjust to 0.6.

[Bleaching solution] Iron ammonium salt of ethylenediaminetetraacetic acid 100.0 g Diammonium salt of ethylenediaminetetraacetic acid 10.0 g Ammonium bromide 150.0 g Glacial acetic acid 10.0 g Water is added to adjust the pH to 1, and the pH is adjusted to 6.0 using aqueous ammonia.

[Fixing solution] Ammonium thiosulfate 175.0 g Anhydrous sodium sulfite 8.6 g Sodium metasulfite 2.3 g Water is added to 1 and the pH is adjusted to 6.0 using acetic acid.

[Stabilizing solution] Formalin (37% by weight) 1.5 ml KONIDAX (manufactured by Konica Corporation) 7.5 ml Add water to make 1.

For the samples 9 to 16 processed as described above, the transmission density was measured using a densitometer (model KD-7R, manufactured by Konica Corporation), and each of the processed samples was subjected to high temperature and high humidity (60 ° C., 80% RH)
It was left for 14 days in an atmosphere, and the heat resistance and humidity resistance of the dye image were examined.

Each sample was irradiated with a xenon fade meter for 10 days, and the light resistance was examined. Table 2 shows the results. However, the heat resistance, moisture resistance, and light resistance of the dye image are represented by the percentage of the dye remaining after the heat resistance, humidity resistance, and light resistance tests with respect to the initial density of 1.0.

As is clear from the results in Table 2, the sample using the coupler of the present invention was compared with the sample using the comparative coupler,
It can be seen that in all cases, the dye remaining ratio is high, the heat resistance and moisture resistance are excellent, and the solidity is high. Further, it can be seen that the light resistance is equal to or higher than that and is excellent.

Example 3 The following layers were sequentially coated on a triacetyl cellulose film support from the support side, and red-sensitive color reversal photographic light-sensitive materials 17 to 22 containing the couplers shown in Table 3 were prepared.

First layer: emulsion layer 1.4 g of gelatin, red-sensitive silver chlorobromide emulsion (silver chloride 96 mol%
A red-sensitive emulsion layer comprising 9.1 × 10 ⁻⁴ mol of the coupler shown in Table 3 dissolved in 0.5 g of dibutyl phthalate and 1.5 g of dibutyl phthalate.

Second layer: protective layer A protective layer containing 0.5 g of gelatin. In addition, 2,4-
Dichloro-6-hydroxy-s-triazine sodium salt was added in an amount of 0.017 g / g of gelatin.

To each sample, an activator and anti-biotic (a mixture of 2-methylisothiazol-3-one and 5-chloro-2-methylisothiazol-3-one) were added.

Each of the samples obtained above was subjected to a wedge exposure according to a conventional method, and then subjected to a development process in the following step.

[Reversal process] Process time Temperature First development 6 minutes 38 ° C Washing water 2 minutes 38 ° C Inversion 2 minutes 38 ° C Color development phenomenon 6 minutes 38 ° C Adjustment 2 minutes 38 ° C Bleaching 6 minutes 38 ° C Fixed 4 minutes 38 ℃ Water washing 4 min 38 ℃ Stability 1 min 38 ℃ Drying room temperature The composition of the treatment liquid used was as follows.

[First developer] Sodium tetrapolyphosphate 2 g Sodium sulfite 20 g Hydroquinone monosulfonate 30 g Sodium carbonate (monohydrate) 30 g 1-phenyl-4-methyl-4-hydroxymethyl-
3-pyrazolyldone 2 g Potassium bromide 2.5 g Potassium thiocyanate 1.2 g Potassium iodide (0.1% solution) 2 ml Add water 1000 ml [Inversion liquid] Nitrilotrimethylenephosphonic acid 6 sodium salt 3 g Stannous chloride (dihydrate salt) 1 g p-Aminophenol 0.1 g Sodium hydroxide 5 g Glacial acetic acid 15 ml Add water 1000 ml [Color developing solution] Sodium tetrapolyphosphate 2 g Sodium sulfite 7 g Sodium tertiary phosphate (12 hydrate) 36 g Potassium bromide 1 g Iodide Potassium (0.1% solution) 90 ml Sodium hydroxide 3 g Citrazinic acid 1.5 g N-ethyl-N- (β-methanesulfonamidoethyl) -3-methyl-4-aminoaniline / sulfate 11 g Ethylenediamine 3 g Water is added to 1000 ml [ Adjustment solution] Sodium sulfite 12g Sodium ethylenediaminetetraacetate (dihydrate) 8g Thioglycerin 0.4ml Glacial acetic acid 3ml Water In addition, 1000 ml [bleach] sodium ethylenediaminetetraacetate (dihydrate) 2.0 g iron (III) ammonium ethylenediaminetetraacetate (2
(Water salt) 120.0 g Potassium bromide 100.0 g Add water 1000 ml [Fixing solution] Ammonium thiosulfate 80.0 g Sodium sulfite 5.0 g Sodium bisulfite 5.0 g Add water 1000 ml [Stabilizing solution] Formalin (37% by weight) 5.0 ml Conidax (Konica Corporation) 5.0 ml 1000 ml of water was added to each of the samples, and the heat resistance, moisture resistance and light resistance of the dye image were examined in the same manner as in Example 2. Table 3 shows the results.

As is clear from Table-3, the samples using the coupler of the present invention all have a higher dye remaining ratio, are superior in heat resistance and moisture resistance, and are more robust than the samples using the comparative coupler. . Further, it can be seen that the light resistance is equal to or higher than that and is excellent.

[Effect of the Invention] The dye image formed from the coupler of the present invention is fast against heat, humidity and light.

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) G03C 7/38

Claims (1)

(57) [Claims] 1. A photographic coupler represented by the general formula [I]. [Wherein R ₁ , R ₂ , R ₃ and Y represent a hydrogen atom or a substituent, and R ₂ and R ₃ may combine to form a ring. X represents a hydrogen atom or a substituent which is eliminated by reaction with an oxidized form of a color developing agent. ]