JPH0136608B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a novel silver halide photosensitive material,
More specifically, the present invention relates to a silver halide photosensitive material in which an image is obtained by coloring a leuco dye formed in an image-like manner using light or heat. Several image forming methods using leuco dyes have been known. For example, Research Disclosure (publication of Industrial Opportunities Ltd., a publisher located in Hampshire, England) Vol. 128 No. 12838, Vol. 12839, and Vol. and an aromatic primary amine compound having an electron-withdrawing group in the phenylene group, and a method for obtaining a dye image by developing color in the presence of silver halide and a cross-oxidizing agent. The specifications of Japanese Patent Application No. 55-28530 and No. 55-121427 describe photosensitive materials containing a leuco dye formed from a cyan coupler and an aromatic compound having a sulfonamide group. In a broad sense, the leuco dye mentioned above is a general term for organic dyes that reversibly change color depending on the oxidized ring element.The reduced type is generally colorless or light colored, and the oxidized type is dark colored, but the real color is In the present invention, reduced dyes are referred to as leuco dyes in contrast to ordinary oxidized dyes. By the way, the biggest drawback of these prior art techniques is that because the entire surface of the photosensitive layer contains leuco dyes, after image formation, dye formation progresses slowly in non-image areas due to air oxidation, light irradiation, heating, etc. In addition to the undesirable occurrence of "fogging," the sensitivity is inevitably lower than that of general photographic methods or light-sensitive materials that are based on image-forming methods that directly form dyes through image exposure. There is no such thing. SUMMARY OF THE INVENTION An object of the present invention is to provide a photosensitive material using a leuco dye that has high sensitivity, reduces fogging, and provides clear dye images. As a result of intensive studies by the present inventors to address the above-mentioned problems, a silver halide photosensitive material having a constituent layer containing a photo- or thermochromic leuco dye-forming compound represented by general formula (1) and a color coupler has been provided. General formula (1)

[Formula] (In the formula, R represents -OH, -NR'R'', -
Ranked 4th in CO compared to NHSO ₂ Y. R′,
R'' each represents a hydrogen atom or a substituted or unsubstituted alkyl group having 1 to 8 carbon atoms, and R' and R'' may be bonded to each other to form a nitrogen-containing saturated heterocycle.

[Formula] represents a substituted or unsubstituted phenylene group or naphthalene group. Y is a substituted or unsubstituted phenyl group, a naphthyl group,
Represents a substituted amino group. ), it has been found that the above objective can be achieved. Among the compounds having a sulfonamide group in the general formula of the present invention, the auxochrome represented by Au is -OH and -NRR' groups, as described above. Here, R and R' are H atoms, alkyl groups having 1 to 8 carbon atoms (e.g., methyl group, ethyl group, propyl group, etc.), or substituted alkyl groups (e.g., β-hydroxyethyl group, β-methoxyethyl group, β-methoxyethyl group, -methylsulfonamidoethyl group, etc.), or in the case of -NRR', R and R' are bonded to each other such that a nitrogen-containing saturated heterocycle (e.g., morpholyl group, piperidyl group, 3-hydroxypiperidyl group, piperazyl group, pyrrolidyl group, imidazolyl group, piperazolyl group, etc.). In the above formula, CO represents a group having at least one conjugated double bond (eg, vinylene group, butadienylene group, phenylene group, substituted phenylene group, methylidenecyclohexynyl group, naphthalene group, etc.). Next, specific examples of the phenomenon agent having a sulfonamide group used in the present invention are shown below. (Exemplary compound) The above developer having a sulfone group according to the present invention can be synthesized by reacting an aromatic primary amine compound and a sulfonyl halide compound. When this developer is contained in a silver halide photosensitive material, it is inert to silver halide, and therefore, even if it is contained in the photosensitive material, it will not have any adverse effect on the photosensitive layer. Next, the color coupler in the present invention includes known couplers commonly used in silver halide color photographic light-sensitive materials. For example, yellow couplers include benzoylacetanilide compounds, pivaloylacetanilide compounds, carbamoylacetamide compounds, etc., and magenta couplers include 5-pyrazolone compounds, pyrazolotriazole compounds, pyrazolinobenzimidazole compounds, indazolone compounds, cyanoacetyl compounds, Cyan couplers include phenol compounds, such as thiazoline compounds,
These include diacylaminophenol compounds and naphthol compounds. In addition to these, cyclic active methylene compounds having at least one carbonyl group in the ring, such as indanone compounds, indandione compounds, thionaphthenone compounds, coumaranone compounds, thioindoxyl compounds, isoxazolone compounds, pyrimidazolone compounds, oxindole compounds, Homophthalimide compounds and the like can also be used. Note that one of the hydrogen atoms at the active site of these couplers has another leaving group, such as halogen, alkoxy, aryloxy, heteroyloxy, sulfonyloxy, acyloxy, acyl, heteroyl, thiocyano, alkylthio, arylthio,
It may also be a so-called active point substituted coupler substituted with heteroylthio, sulfonamide, phosphonyloxy, arylazo, or the like. The developer according to the present invention usually contains 0.5 to 500 mol% of the silver halide contained per unit area.
It is preferably used in a range of 5 to 150 mol%.
The above color coupler is used in an amount equal to or slightly larger than that of the developer. The method of incorporating the developing agent and color coupler according to the present invention into the emulsion layer of the silver halide light-sensitive material is not particularly limited, but any method known for conventional silver halide color photographic light-sensitive materials can be used. That is, as shown in U.S. Pat. No. 2,322,027, the oil is dissolved in a high boiling point solvent and dispersed as fine oil droplets, or as shown in U.S. Pat.
As shown in No. 2186849, a method of dissolving and dispersing a diffusion-resistant group and a water-soluble group, as shown in U.S. Pat. No. 2,397,864, a method of incorporating it as a component of a polymer compound, or
As shown in Japanese Patent No. 59942 and No. 51-59943, there are methods of filling latex polymers, and methods of mechanically pulverizing and dispersing them using a colloid mill or the like. As the silver halide used in the present invention, all those used in ordinary silver halide photosensitive materials can be used. For example, in addition to silver chloride, silver bromide, and silver iodide, mixed silver halides such as silver chlorobromide, silver iodobromide, silver chloroiodide, and silver chloroiodobromide can be used. These silver halide emulsions can be produced by conventional methods, such as an ammonia method, a neutral method, an acid method, a halogen conversion method, a function addition method, and a homogeneous precipitation method. Although the average diameter of the grains is not limited, it is preferably from 0.01 .mu.m to 5 .mu.m. Alternatively, two or more types of silver halide emulsions formed separately may be used as a mixture. Furthermore, a monodisperse emulsion may be used without any problem. The silver halide emulsion that can be used in the present invention can be chemically sensitized using a conventional method. In other words, gold sensitization using gold complex salts, reduction sensitization using reducing substances, sulfur sensitization using compounds containing sulfur that can react with silver ions, or so-called activated gelatin, and noble metals belonging to group 3 of the periodic table. A sensitization method using a salt of can be used. The silver halide emulsion that can be used in the present invention can be subjected to spectral sensitization. The method is as follows:
Cyanine dyes such as monomethine cyanine, pentamethine cyanine, merocyanine, and carbocyanine can be used alone or in combination, or they can be used in combination with styryl dyes or aminostilpene compounds. Silver halide emulsions that can be used in the present invention include known stabilizers, antifoggants, surfactants, antifoaming agents,
Additives such as an antistatic agent, a hardening agent, a film property improver, a whitening agent, an anti-staining agent, an ultraviolet absorber, and an anti-irradiation agent can be included. Regarding these various additives, please refer to Research Disclosure Section.
All items listed in Volume 176 No. 17643 (1978) can be used. Furthermore, cross-oxidizing agents well known in the art can be effectively used in the silver halide photosensitive material of the present invention. Examples of cross-oxidizing agents include aminophenol compounds, phenylenediamine compounds, 3-pyrazolidone compounds, azine compounds, and bipyridium compounds. Specific examples of cross-oxidizing agents are shown below. In the present invention, if the silver halide light-sensitive material requires a support, any support used in ordinary printed matter or photographic light-sensitive materials can be used. Examples include glass, metal, ceramics, wood, paper, synthetic paper, cellulose acetate film, polyethylene terephthalate film, polystyrene film, polycarbonate film, laminates thereof, and polyolefin-coated paper. In the present invention, when the silver halide photosensitive material requires a binder or a protective colloid, it is advantageous to use gelatin, but other hydrophilic colloids, such as gelatin derivatives, gelatin and other polymers, are advantageously used. Graft polymers, cellulose derivatives such as hydroxyethyl cellulose, sulfoxymethyl cellulose, cellulose sulfate esters, monomers such as polyvinyl alcohol, polyvinyl alcohol partial acetal, poly-N-vinylpyrrolidone, polyacrylic acid, polymethacrylic acid, polyacrylamide, etc. Various synthetic hydrophilic substances such as monopolymers or copolymers can be used alone or in combination, or mixed with gelatin. By exposing and developing the silver halide photosensitive material of the present invention as described in detail above, an oxidation reaction sufficient to form a leuco dye between the color coupler and the color coupler, which is the leuco dye-forming compound of the present invention, occurs. However, this level of oxidation reaction cannot further convert leuco dyes into normal dyes. The above-mentioned leuco dyes form a chromophore when exposed to light such as ultraviolet light, visible light, infrared light, or heat, and a coloring action occurs. In the present invention, the speed at which the above-mentioned leuco dye is converted into a dye by light or heat, the maximum absorption wavelength, molar extinction coefficient, etc. of the converted dye are determined by the size of the conjugated system, the type of chromophore, Types of electron-withdrawing groups and electron-donating groups that are chromophores, their ionization, cyclization, short-circuiting of conjugated systems due to the introduction of other substituents, steric hindrance, hydrogen bonding, or intramolecular or intermolecular metal complexes. It is necessary to take into account that it is influenced by the formation of pigments and the medium of the dye. After image exposure, the silver halide photographic material of the present invention is generally processed according to the following processing steps. First, the first step is a step in which the developer and coupler are converted into photo- or thermochromic leuco dyes by the selective oxidation effect that occurs when the image-exposed silver halide is developed. In this step, the necessary conditions for the above reaction to proceed include an alkaline bath with an appropriate buffering effect, salts to adjust ionic strength and salt concentration, and silver halide as necessary. During development, an antifoggant, the above-mentioned cross-oxidizing agent, a thickener, a surfactant, etc. may be further used in combination. After the photo- or thermochromic leuco dye is imagewise formed as described above, undeveloped silver halide in the light-sensitive material is preferably removed. Moreover, the silver image obtained by development may or may not be removed. For these steps, the fixing treatment, bleaching treatment, or bleach-fixing treatment that can be applied to silver halide photographic light-sensitive materials is directly applied. Furthermore, stopping treatment, water washing treatment, stabilization treatment, etc. may be provided at any part of these treatment steps as necessary. The present invention not only provides a silver halide light-sensitive material in which the resulting dye is monochromatic, but also provides a silver halide photosensitive material in which the resulting dye is, for example,
Color photosensitive materials can also be provided by appropriately selecting a developer and a coupler so as to provide yellow, magenta, and cyan. In addition to application to ordinary photosensitive materials, for example, it can also be applied to diffusion transfer methods in which images are obtained by diffusing dyes, dye precursors, developers, etc.
The leuco dye-forming compounds, couplers or formed leuco dyes of the invention can be advantageously used. The silver halide photosensitive material of the present invention will be specifically explained below with reference to Examples. EXAMPLE The following components were coated onto a polyethylene laminated paper support containing a white pigment. Ossein gelatin 1.8 g/m ² Silver chlorobromide (in terms of silver) 0.8 g/m ² Exemplary compound (B-7) 1.0 g/m ² Coupler 3.0×10 ^-3 mol/m ² Exemplary cross-oxidizing agent (C-12) 0.66g/m ² Gelatin hardening agent (bisvinylsulfonyl methyl ether)
28mg/m ² Among the above components, the following four types of color couplers were used. (Sample-A) (Sample-B) (Sample-C) (Sample-D) Next, as comparative samples, samples containing the following leuco dyes (Sample-E) and (Sample-F) in place of the color coupler and exemplified compound (B-7) of the above sample were also prepared. (Sample-E) (Sample-F) (Sample-G) Exemplified Compound B-1 was used in place of Exemplified Compound B-7. The above samples A to G were exposed using a step wedge and a sensitometer at 500 CMS for 0.5 seconds, and then processed using the following processing steps and processing solution. (Processing steps) 1 Activator bath 30°C 3 minutes 2 Bleach-fixing bath 30°C 1 minute 3 Water washing 18-22°C 5 minutes However, the composition of each treatment liquid is as follows. (Activator liquid) Benzyl alcohol 10ml Disodium phosphate dodecahydrate 36g Potassium bromide 0.6g Sodium polymethanoate 1.0g Add water to make 1, and adjust the pH with sodium hydroxide.
Adjust to 12.0. (Bleach solid solution) Iron ammonium ethylenediaminetetraacetate 60g Diammonium ethylenediaminetetraacetate 5g Ammonium thiosulfate 13.4g Anhydrous sodium sulfite 3g Add water to bring the pH to 1, and adjust the pH with aqueous ammonia.
Adjust to 7.0. Among the obtained samples, Samples A to D were colorless, Sample E had a fog density of 0.30 and a maximum density of 0.82, and Sample F had a fog density of 0.22. These samples A~
A low-pressure mercury lamp is used as a light source for the entire surface of G.
Bright line light irradiation was performed at 253.7 nm. The fog density and maximum density of the sample at that time are shown in Table 1 below.

【table】

[Table] (However, both fog density and maximum density are the density at λmax of each dye formed.) As is clear from the above table, the photosensitive material of the present invention in which leuco dyes are formed in an imagewise manner is Images with sufficient maximum density can be obtained with almost no fog unlike conventional techniques. In the above embodiment, the present invention also applies when irradiating with tungsten light, household fluorescent lamp, sunlight, xenon arc lamp, etc. instead of the bright line light of a low-pressure mercury lamp, or when leaving it in an atmosphere at 77°C with light shielded. With the sample, a clear, high-density step wedge image could be obtained without fogging.

Claims (1)

[Scope of Claims] 1. A silver halide photosensitive material having a constituent layer containing a photo- or thermochromic leuco dye-forming compound represented by general formula (1) and a color coupler. General formula (1) [Formula] (In the formula, R represents -OH, -NR'R'', -
Ranked 4th in CO compared to NHSO ₂ Y. R′,
R'' each represents a hydrogen atom or a substituted or unsubstituted alkyl group having 1 to 8 carbon atoms, and R' and R'' may be bonded to each other to form a nitrogen-containing saturated heterocycle. [Formula] represents a substituted or unsubstituted phenylene group or naphthalene group. Y is a substituted or unsubstituted phenyl group, a naphthyl group,
Represents a substituted amino group. )