JPH0481783B2 - - Google Patents

Description

[Detailed description of the invention]

(Industrial Application Field) The present invention relates to a silver halide photographic material,
This invention relates to a silver halide photographic material in which photographic additives that are difficult to tolerate in water are dispersed in a hydrophilic organic colloid layer using a high-boiling organic solvent containing chlorine atoms, and are particularly suitable for rapid processing conditions. However, it concerns a photographic paper that can provide good whiteness of the base. (Prior Art) It is a well-known technique to apply fluorescent brighteners to increase the whiteness of photographic materials after processing. In recent years, there has been a demand for photographic materials that can be easily and quickly processed. Therefore, black and white developing agents such as hydroquinones, metols, phenidone, etc., and color developing agents such as p-
Many technologies have been developed, such as incorporating phenylenediamine derivatives into photosensitive materials and high-temperature processing for rapid processing. Under such conditions, increasing whiteness by fluorescent whitening is becoming an increasingly important requirement in providing photographic paper with good appearance. Of course, it goes without saying that the fluorescent whitening method is a method that can be generally applied to improve the apparent whiteness regardless of the presence or absence of residual color. Such fluorescent whitening methods have been known for a long time, for example, Japanese Patent Application Laid-Open No. 117-1982, US Pat. No. 3,449,257, and US Pat.
No. 3,558,316, in which a fluorescent brightener is added to the paper support or its polyethylene laminate layer; Brighteners or oil-soluble fluorescent brighteners can be added directly or into the polymer as disclosed in Japanese Patent Publications No. 45-37376, No. 45-11111, No. 51-47043, and U.S. Pat. Adding a dispersion of a fluorescent brightener to a photographic dispersant, adding a dispersion of a fluorescent brightener to a photographic dispersant, or adding a fluorescent brightener such as a water-soluble diaminostilbene derivative to a developing solution. A method is known in which the fluorescent brightener is added in advance to the photosensitive material and then impregnated into the photosensitive material during the development process. However, in the case of polyethylene laminated paper, which is particularly suitable for rapid processing, when trying to incorporate a fluorescent brightener into the laminate layer, the thermal stability of the fluorescent brightener is poor, making it difficult to heat extrude during the formation of the laminate layer. Not only do fluorescent brighteners have disadvantages such as being easily decomposed during the process, but also have the disadvantage that fluorescent brighteners have poor heat-resistant sublimation properties, which can cause them to adhere to manufacturing machines and cause manufacturing failures. With this method, it is clear that the amount of fluorescent brightener added must be adjusted in order to produce photosensitive materials suitable for a wide variety of purposes, which requires a lot of time, effort, and cost. has its limitations, and very few are actually used in manufacturing. Also, if you try to impregnate a fluorescent brightener during the development process, the desired amount of fluorescent brightener may not penetrate within the desired time, and the water washing process at the end of the processing process may On the other hand, it has the drawback that sufficient whiteness cannot be obtained because a part of it flows out. Therefore, during the development process, there are inconveniences such as the uniformity of the finish being impossible to maintain unless the density is maintained at a constant level. Most preferred. In particular, in the method of adding a fluorescent brightener to the photographic layer, an oil-soluble fluorescent brightener is used rather than a water-soluble one to prevent the fluorescent brightener from being washed away during the development process. For this purpose, it is effective to include a water-insoluble fluorescent brightener in an organic solvent to form an emulsified dispersion of gelatin, as described in British Patent No. 1072915. A method of adding it into a layer is known. For example, dibutyl phthalate, cresyl phosphate, etc. are often used as organic solvents, and amide compounds described in US Pat. No. 2,322,027 are known as organic solvents suitable for emulsifying fluorescent brighteners. . High boiling point organic solvents such as phthalate ester compounds, amide compounds and phosphate ester compounds are used not only for fluorescent whitening agents but also for the dispersibility of other poorly water-soluble photographic additives, gelatin, etc. It has been used relatively often because it has excellent compatibility with the colloid layer, chemical stability in photosensitive materials, and availability at low cost. However, like the above-mentioned method of dispersing in polymers, the conventional techniques are still insufficient to provide high-performance light-sensitive materials with excellent whiteness. That is, in order to provide excellent whiteness even during rapid processing and high temperature processing, the desired amount of fluorescent brightener cannot be dissolved and dispersed in an amount of organic solvent that does not impair other photographic properties, or even if it can be dissolved. It has the disadvantage that it precipitates or decomposes during the production or storage of photosensitive materials, leading to a decrease in whiteness, and sometimes even producing stains. In order to improve the whiteness, the fluorescence intensity of the fluorescent brightener, the fluorescence emission spectral distribution,
Photothermal stability is an important factor, and many fluorescent brighteners have been developed to improve fluorescence intensity and photothermal stability. At present, it has a strong tendency to become insoluble in organic solvents that have few negative effects photographically, and is therefore not fully utilized. Furthermore, it is known that the fluorescence intensity, fluorescence emission spectrum, and photothermal stability are greatly influenced not only by the fluorescent brightener but also by the organic solvent in which it is dissolved and dispersed, and are often affected by the quenching effects of other coexisting compounds. ing. Many compounds are added to high-performance photographic materials, and many compounds are also added to processing solutions for development and the like. Some of these substances have a quenching effect, and it is preferable that the organic solvent in which the fluorescent brightener is dissolved and dispersed not incorporate such quenching substances. Therefore, in a method of dissolving and dispersing a poorly water-soluble fluorescent brightener in a high boiling point organic solvent and dispersing it in a photographic material, which is particularly preferred for the production of photographic light-sensitive materials, in order to improve the whiteness, It has no adverse effects and has high solubility in poorly water-soluble fluorescent brighteners.
A fluorescent brightener that provides strong fluorescent light emission intensity and a desired emission spectrum distribution, does not deteriorate itself during production and storage, does not deteriorate dissolved fluorescent brighteners, and is contained in photographic materials and processing solutions. There has been a need for high boiling point organic solvents that do not dissolve added quenching substances. There has been a continuing desire for the development of a technology that can provide photographic materials with excellent whiteness by using such excellent high-boiling point organic solvents and excellent fluorescent whitening agents. (Object of the Invention) Therefore, the first object of the present invention is to provide a silver halide photographic light-sensitive material containing a substantially water-insoluble fluorescent brightener and having excellent whiteness, especially a silver halide photographic print. The second purpose is to incorporate a development accelerator such as a developing agent into the photographic layer, add the development accelerator to the development solution, and increase the development temperature to 30°C. In such cases, photographic materials with high whiteness that have been made suitable for rapid development by heating the temperature to 40°C or higher, and photographic materials with high whiteness that are subjected to rapid development, especially An object of the present invention is to provide silver halide photographic paper. Another object of the present invention is to provide a technique for incorporating a slightly water-soluble fluorescent brightener into a hydrophilic colloid layer, and another object of the present invention is to provide a technique for incorporating a fluorescent brightener that is poorly soluble in water into a hydrophilic colloid layer. An object of the present invention is to provide a dispersion technology for a fluorescent brightener that has high strength and excellent photothermal stability. Another object of the present invention is to provide a photographic material that does not lose its whiteness during storage. Another object of the present invention is to provide a photographic material that has sufficient whiteness without precipitation of a fluorescent brightener during storage. (Structure of the Invention) These objects of the present invention are to combine a high boiling point organic solvent selected from compounds represented by the following general formulas -1 and -2 and chlorinated paraffin compounds, and the following general formulas (-a) and (-b). , (-c) and (-d)
This was achieved using a silver halide photosensitive material characterized in that the hydrophilic colloid layer contains a water-insoluble optical brightener selected from the compounds represented by: Here, X and Y represent a hydrogen atom, an alkyl group, an alkoxy group, R ₁ , R ₂ and R ₃ represent an optionally substituted acyclic alkyl group, and m and n represent 1 or 2. However, the total number of carbon atoms in X and R ₁ is 8 or more, and the total number of carbon atoms in Y, R ₂ and R ₃ is 7 or more. Here, Y ₁ and Y ₂ are optionally substituted alkyl groups, alkoxy groups, alkoxycarbonyl groups, Z ₁
and Z ₂ is hydrogen or an optionally substituted alkyl group, n is 1 or 2, R ₁ , R ₂ , R ₃ , R ₄ , R ₅ ,
R ₆ , R ₇ , R ₈ , R ₉ , R ₁₀ and R ₁₁ are optionally substituted aryl, optionally substituted alkyl, alkoxy, aryloxy, hydroxyl, amino, cyano, carboxyl, amide, ester, alkylcarbonyl, alkyl It is a sulfone or dialkylsulfamoyl group or a hydrogen atom. R ₆ and R ₇ are a hydrogen atom, an alkyl group such as a methyl group, an ethyl group, or a cyano group. R ₁₃ is a phenyl group, a halogen atom, or an alkyl-substituted phenyl group. R ₁₂ is an optionally substituted alkyl group or an organic primary or secondary amine. In the present invention, the most useful fluorescent brighteners are compounds of the general formula -
It is a 2,5-bisbenzoxazolylthionephene compound represented by a, and in the general formula -a
Either the total number of carbon atoms in the alkyl moieties of Y ₁ , Y ₂ , Z ₁ , and Z ₂ is 8 or more and 30 or less, or two or more of these substituents have a branched alkyl moiety, or at least one of them has a branched alkyl moiety. It has six or more branched alkyl moieties. Next, specific examples of the water-insoluble fluorescent whitening agent used in the present invention will be given, but the present invention is not limited thereto. The organic solvent used in the present invention is a compound represented by the structural formula of the following general formula or a chlorinated paraffin compound. Here, X and Y represent a hydrogen atom, an alkyl group, an alkoxy group, R ₁ , R ₂ and R ₃ represent an optionally substituted alkyl group, and m and n represent 1 or 2. However, the total number of carbon atoms in X and R ₁ is 8 or more, and the total number of carbon atoms in Y, R ₂ and R ₃ is 7 or more. The chlorinated paraffin preferably has a chlorine content of 30% to 80% by weight, a molecular weight of 400 to 1500, and is liquid at room temperature. Next, specific examples of high boiling point organic solvents used in the present invention will be given, but the present invention is not limited thereto. S-7 Empara 40 (chlorine content 40%, Ajinomoto Co., Inc.)
Commercial product, C ₂₄ H ₄₄ Cl ₆ ) S-8 Empara 70 (chlorine content 70%, Ajinomoto Co., Inc.)
Commercial product, C ₂₄ H ₂₉ Cl ₂₁ ) S-9 Empara K-45 (chlorine content 45%, Ajinomoto Co., Inc., commercial product, C ₁₄ H _25.5 Cl _4.5 ) S-10 Empara K-50 (chlorine content 50%, Ajinomoto Co., Inc., commercial product, C ₁₄ H ₂₄ Cl ₆ ) S-11 Empara K-65 (chlorine content 65%, Ajinomoto Co., commercial product, C ₁₂ H ₁₈ Cl ₈ ) The high boiling point organic solvents of the present invention may be used alone or in combination of two or more. When using a combination of two or more types, as long as one of them is liquid at room temperature, the other may be solid, but in that case, it is preferable that the melting point or softening point is 65°C or lower, and that it becomes liquid in the mixed state. Preferably. Of course, when used alone, it may be solid at room temperature as long as it has a melting point of 65°C or less or has a solubility in a volatile low-boiling auxiliary solvent such as ethyl acetate of 100 or more, and when used in combination, it may be solid at room temperature. Although it may be a liquid, it is more preferable to be a liquid. The preferred high boiling point organic solvent in the present invention is one of the above-mentioned compounds with a chlorine content of 35% by weight or more and 70% by weight.
It is a chlorinated paraffin with a molecular weight of 450 or more and 1200 or less in weight percent or less. In particular, when such chlorinated paraffin is used, if 20% by weight or more of the total high-boiling point organic solvent is used, high-boiling point organic solvents used in combination are conventionally known, and dispersion of other photographic oil-soluble additives is possible. It has been found that the objects of the present invention can be achieved even with ordinary phthalate ester compounds and phosphate ester compounds that have been used as solvents. The method for adding the oil-soluble fluorescent brightener is the same as conventionally used for oil-soluble couplers and oil-soluble ultraviolet absorbers, that is, ethyl acetate is added to a high boiling point organic solvent containing chlorine atoms as necessary. It is dissolved with a low boiling point solvent such as and mixed with an aqueous gelatin solution containing a surfactant, and then used in a colloid mill, homogenizer, etc.
At least one of the silver halide photographic light-sensitive materials is prepared as an emulsified dispersion using an emulsifying device such as an ultrasonic dispersing device.
added into the layer. It can be added to a photosensitive layer containing a silver halide emulsion, or to a non-photosensitive hydrocolloid layer such as an undercoat layer, an intermediate layer, or a protective layer. From this point of view, it can be added to a silver halide emulsion layer or a layer closer to the support (hydrophilic colloid layer such as an undercoat layer or an intermediate layer). The amount of fluorescent brightener used is 1% in the finished photographic paper.
It is preferably added in an amount of ~200 mg/ ^m2 , and most preferably in a range of 5 to 50 mg/ ^m2 . As the binder or protective colloid that can be used in the emulsion layer or hydrophilic colloid layer (e.g., protective layer, intermediate layer) of the light-sensitive material of the present invention, it is advantageous to use gelatin, but other hydrophilic Colloids can also be used. For example, gelatin derivatives, graft polymers of gelatin and other polymers, proteins such as albumin and casein; cellulose derivatives such as hydroxyethyl cellulose, carboxymethyl cellulose, and cellulose sulfates; sugar derivatives such as sodium alginate and starch derivatives; polyvinyl alcohol , polyvinyl alcohol partial acetal,
Poly-N-vinylpyrrolidone, polyacrylic acid,
A wide variety of synthetic hydrophilic polymeric materials can be used, such as single or copolymers of polymethacrylic acid, polyacrylamide, polyvinylimidazole, polyvinylpyrazole, and the like. In addition to lime-processed gelatin, acid-processed gelatin, Bull.Soc.Sci.Phot.Japan, No. 16,
Enzyme-treated gelatin as described in P30 (1966) may be used, and gelatin hydrolysates and enzymatically decomposed products may also be used. Any of silver bromide, silver iodobromide, silver iodochlorobromide, silver chlorobromide and silver chloride may be used as silver halide in the photographic emulsion layer of the photographic light-sensitive material used in the present invention. The average grain size of the silver halide grains in the photographic emulsion (the grain size is the grain diameter in the case of spherical or approximately spherical grains, the ridge length in the case of cubic grains,
Expressed as an average based on projected area. ) are not particularly asked. The particle size distribution may be narrow or wide. The silver halide grains may have different phases inside and on the surface. Further, the particles may be particles in which a latent image is mainly formed on the surface, or may be particles in which a latent image is mainly formed inside the particle. The shape of the silver halide grains may be cubic, regular octahedral, tetradecahedral with [100] and [111] faces, twinned, or tabular. The photographic emulsion used in the present invention is written by P. Glafkides.
Chimie et Physique Photographique (Paul Montel, 1967),
Written by GFDuffin Photographic Emulsion Chemistry (The
Focal Press, 1966), VLZelikman et al.
AuthorMaking and Coating Photographic
It can be prepared using the method described in Emulsion (The Focal Press, 1964).
That is, any of the acidic method, neutral method, ammonia method, etc. may be used, and the method for reacting the soluble silver salt with the soluble halogen salt may be any one-sided mixing method, simultaneous mixing method, or a combination thereof. good. It is also possible to use a method in which particles are formed in an excess of silver ions (so-called back-mixing method).
One type of simultaneous mixing method is a method of keeping pAg constant in the liquid phase in which silver halide is produced, that is,
A so-called controlled double jet method may also be used. According to this method, a silver halide emulsion having a regular crystal shape and a nearly uniform grain size can be obtained. Two or more types of silver halide emulsions formed separately may be mixed and used. In the process of silver halide grain formation or physical ripening, cadmium salts, zinc salts, lead salts, thallium salts, iridium salts or complex salts thereof, rhodium salts or complex salts thereof, iron salts or iron complex salts, etc. may be allowed to coexist. In addition, silver halide solvents such as ammonia, thioethers (e.g., 1,2-bis(2-hydroxyethylthio)ethane, etc.), thioureas, (e.g., tetramethylthiourea, etc.) may be present, and grain formation Afterwards, if these silver halide solvents are unnecessary, oxidation treatment with hydrogen peroxide or the like may be performed. Even if the silver halide emulsion is chemically sensitized,
You don't have to be there. Silver halide emulsions are usually chemically sensitized.
For chemical sensitization, see for example “Die
Grundlagender Photographischen Prozesse
mit Silber−halogeniden” (Akademische
Verlagsgesellschaft.1968) pages 675-734 can be used. That is, sulfur sensitization using sulfur-containing compounds that can react with active gelatin and silver (e.g., thiosulfates, thioureas, mercapto compounds, rhodanines); reducing substances (e.g., stannous salts, amines, hydrazine derivatives, formamidine sulfinic acid, silane compounds) reduction sensitization method;
Precious metal compounds (e.g., gold complex salts, Pt, It,
A noble metal sensitization method using complex salts of metals in the periodic table group such as Pd can be used alone or in combination. A silver halide developing agent and a developing agent precursor, which are development activators capable of developing silver halide in an alkaline solution, are used in the present invention for the purpose of adapting to rapid development processing in which the effectiveness of the present invention is particularly exhibited. It can be added to photographic emulsion layers or non-photosensitive hydrophilic colloid layers. By using the method of the present invention, even if such a compound is used, high whiteness can be obtained without causing a decrease in fluorescence intensity due to quenching effect. Specific examples of silver halide developing agents include hydroquinone, 2-methylhydroquinone,
2,5-dimethylhydroquinone, trimethylhydroquinone, 2-chlorohydroquinone, 2
- Substituted or unsubstituted dihydroxybenzene compounds such as phenyl-hydroquinone, 2-tert-butylhydroquinone, catechol, and 4-tert-butyl-catechol; Polyhydric phenol compounds such as pyrogallol; 1-phenyl-3-pyrazolidone (phenidone); , 1-(m-tolyl)-3-pyrazolidone, 1-phenyl-2-acetyl-3-pyrazolidone, 1-phenyl-4-methyl-3-pyrazolidone, 1-phenyl-4,4-dimethyl-
3-pyrazolidone, 1-phenyl-4-methyl-
4-hydroxymethyl-3-pyrazolidone, 1-
p-chlorophenyl-4-methyl-4-hydroxy-3-pyrazolidone, 1-(p-tolyl)-4,
4-dihydroxymethyl-3-pyrazolidone, 1
3-pyrazolidone compounds such as -phenyl-4-hydroxymethyl-3-pyrazolidone; amino-phenolic compounds such as p-amino-phenol, 2-amino-4-methyl-phenol, metol, 4-hydroxyphenylaminoacetic acid: p-phenylenediamino, 4-(N,N-diethyl)aminoaniline, 4-(N-ethyl-N-hydroxyethyl)aminoaniline, 4-(N-ethyl-
N-β-methylsulfonaminoethyl)amino-2-methylaniline, 4-(N-ethyl-N-
4-aminoaniline compounds such as hydroxyethyl)amino-2-methylaniline and their salts such as hydrochloride, sulfate, p-toluenesulfonate, and tetraphenylpolone salt: aminohexose reductone compounds; Examples include naphthalene diol, aminonaphthalene diol, and hydrazine. Further, as specific examples of the developing agent precursor substance, for example, 4-chloroacetyloxy-hydroquinone, hydroquinone monoacetate, 1,4-dichloroacetyloxy-
Hydroquinone, 1,4-diacetyloxy-hydroquinone, catechol monobenzoate, 2
-Methylhydroquinone monoacetate, hydroquinone monobenzoate, 2-methoxyhydroquinone monobenzoate and the like. The photographic emulsion used in the present invention can contain various compounds for the purpose of preventing fog during the manufacturing process, storage, or photographic processing of the light-sensitive material, or for stabilizing photographic performance. That is, azoles such as benzothiazolium salts, nitroimidazoles, nitrobenzimidazoles, chlorobenzimidazoles, bromobenzimidazoles, mercaptothiazoles, methicaptobenzothiazoles, mercaptobenzimidazoles, mercaptothiadiazoles, amino Triazoles, benzotriazoles, nitrobenzotriazoles, mercaptotetrazoles (especially 1-phenyl-5-methylcaptotetrazole), etc.; mercaptovirimidines; mercaptotriazines; thioketo compounds such as oxazolinthione; azaindenes, For example, triazaindenes, tetraazaindenes (especially 4-hydroxy substituted (1,
3,3a,7) tetraazaindenes), pentaazaindenes, etc.; known as antifoggants or stabilizers such as benzenethiosulfonic acid, benzenesulfonic acid, benzenesulfonic acid amide, etc.; Many compounds can be added. For more detailed examples of these and how to use them, see, for example, U.S. Pat. No. 3,954,474;
Those described in No. 3982947 and Japanese Patent Publication No. 52-28660 can be used. The photographic emulsion layer or other hydrophilic colloid layer of the light-sensitive material produced using the present invention may contain coating aids, antistatic properties, smoothness improvement, emulsification dispersion, adhesion prevention, and improvement of photographic properties (e.g., development acceleration, high contrast , sensitization)
Various surfactants may be included for various purposes. For example, saponins (steroids), alkylene oxide derivatives (e.g. polyethylene glycol, polyethylene glycol/polypropylene glycol condensates, polyethylene glycol alkyl ethers or polyethylene glycol alkyl aryl ethers, polyethylene glycol esters, polyethylene glycol sorbitan esters, polyalkylene glycols) Nonionic interfaces such as alkylamines or amides, polyethylene oxide adducts of silicone), glycidol derivatives (e.g. alkenylsuccinic acid polyglycerides, alkylphenol polyglycerides), fatty acid esters of polyhydric alcohols, alkyl esters of sugars, etc. Activator: Alkyl carboxylate, alkyl sulfonate, alkylbenzene sulfonate, alkylnaphthalene sulfonate, alkyl sulfate, alkyl phosphate, N-acyl-N-alkyl taurine, sulfosuccinic acid Contains acidic groups such as carboxy groups, sulfo groups, phospho groups, sulfate ester groups, phosphate ester groups, etc., such as esters, sulfoalkyl polyoxyethylene alkyl phenyl ethers, polyoxyethylene alkyl phosphate esters, etc. Anionic surfactants; amphoteric surfactants such as amino acids, aminoalkyl sulfonic acids, aminoalkyl sulfates or phosphates, alkyl betaines, amine oxides; alkylamine salts, aliphatic or aromatic quaternary ammonium salts Cationic surfactants such as heterocyclic quaternary ammonium salts such as , pyridinium, imidazolium, and phosphonium or sulfonium salts containing aliphatic or heterocycles can be used. The photographic emulsion layer of the photographic light-sensitive material of the present invention contains, for example, polyalkylene oxide or its derivatives such as ethers, esters, and amines, thioether compounds, thiomorpholins, and quaternary ammonium salts for the purpose of increasing sensitivity, increasing contrast, or accelerating development. compounds, urethane derivatives, urea derivatives, imidazole derivatives, 3-pyrazolidones, and the like. The photographic light-sensitive material used in the present invention may contain a dispersion of a water-insoluble or sparingly soluble synthetic polymer in the photographic emulsion layer or other hydrophilic colloid layer for the purpose of improving dimensional stability. For example, alkyl (meth)acrylate, alkoxyalkyl (meth)
Acrylate, glycidyl (meth)acrylate, (meth)acrylamide, vinyl ester (e.g. vinyl acetate), acrylonitrile, olefin, styrene, etc. alone or in combination, or together with acrylic acid, methacrylic acid, α,β-unsaturated dicarboxylic acid, Hydroxyalkyl (meth)
Polymers containing a combination of acrylate, sulfoalkyl (meth)acrylate, styrene sulfonic acid, etc. as monomer components can be used. The photographic emulsions used in the present invention may be spectrally sensitized with methyl dyes and others. The pigments used include cyanine pigments, merocyanine pigments,
Included are complex cyanine dyes, complex merocyanine dyes, holopolar cyanine dyes, hemicyanine dyes, styryl dyes and hemioxonol dyes. Particularly useful dyes are those belonging to the cyanine dyes, merocyanine dyes, and complex merocyanine dyes. Any of the nuclei commonly used for cyanine dyes can be used as the basic heterocyclic nucleus for these dyes. That is, pyrroline nucleus, oxazoline nucleus, thiazoline nucleus, pyrrole nucleus, oxazole nucleus, thiazole nucleus, selenazole nucleus, imidazole nucleus, tetrazole nucleus, pyridine nucleus, etc.; a nucleus in which an alicyclic hydrocarbon ring is fused to these nuclei; and these A nucleus in which an aromatic hydrocarbon ring is fused to the nucleus of Nucleus, quinoline nucleus, etc. can be applied.
These nuclei may be substituted on carbon atoms. The merocyanine dye or composite merocyanine dye includes a nucleus having a ketomethylene structure such as a pyrazolin-5-one nucleus, a thiohydantoin nucleus, a 2-thioxazolidine-2,4-dione nucleus, a thiazolidine-2,4-dione nucleus, a rhodanine nucleus, A 5- to 6-membered heteroartic ring nucleus such as a thiobarbituric acid nucleus can be applied. Such a spectral sensitizer may be added in any step of the silver halide grain formation step, physical ripening step, chemical sensitization step, or after the chemical sensitization step and immediately before coating. Often, it may be added in portions in a plurality of these steps. The invention is also applicable to multilayer, multicolor photographic materials having at least two different spectral sensitivities on the support. A multilayer natural color photographic material usually has at least one each of a red-sensitive emulsion layer, a green-sensitive emulsion layer, and a blue-sensitive emulsion layer on a support. The order of these layers can be arbitrarily selected as required. Usually, the red-sensitive emulsion layer contains a cyan-forming coupler, the green-sensitive emulsion layer contains a magenta-forming coupler, and the blue-sensitive emulsion layer contains a yellow-forming coupler, but different combinations may be used depending on the case. The photographic emulsion layer of the photographic light-sensitive material prepared using the present invention contains a dye-forming coupler, that is, an aromatic primary amine developer (e.g., phenylene diamine derivative, aminophenol derivative, etc.) in the color development process. A compound capable of developing color through oxidative coupling may also be used. For example, magenta couplers include 5-pyrazolone couplers, pyrazolobenzimidazole couplers, cyanoacetylcoumarone couplers, open-chain acylacetonitrile couplers, and yellow couplers include acylacetamide couplers (e.g., benzoylacetanilides, pivaloylacetanilides),
Examples of cyan couplers include naphthol couplers and phenol couplers. These couplers are preferably non-diffusible and have a hydrophobic group called a ballast group in their molecules, or are polymerized. The coupler may be either 4-equivalent or 2-equivalent to silver ions. In addition, colored couplers have the effect of color correction,
Alternatively, during development, a development inhibitor or development accelerator is released (so-called DIR coupler or
DAR coupler). The photographic material of the present invention may contain an inorganic or organic hardener in the photographic emulsion layer or other hydrophilic colloid layer. For example, chromium salts (chromium alum, chromium acetate, etc.), aldehydes (formaldehyde, glyoxal, glitaraldehyde, etc.), N-methylol compounds (dimethylol urea, methyloldimethylhydantoin, etc.),
Dioxane derivatives (2,3-dihydroxydioxane, etc.), active vinyl compounds (1,3,5-triacryloyl-hexahydro-s-triazine, 1,3-vinylsulfonyl-2-propanol, etc.), active halogen compounds (2,3-dihydroxydioxane, etc.), (4-dichloro-6-hydroxy-s-triazine, etc.), mucohalogen acids (mucochloric acid, mucophenoxychloroic acid, etc.), and the like can be used alone or in combination. In the photosensitive material produced using the present invention, when dyes, ultraviolet absorbers, etc. are contained in the hydrophilic colloid layer, they may be mordanted with a cationic polymer or the like. The light-sensitive material produced using the present invention may contain a hydroquinone derivative, an aminophenol derivative, a gallic acid derivative, an ascorbic acid derivative, etc. as a color antifoggant. The photosensitive material produced using the present invention may contain a water-soluble dye in the hydrophilic colloid layer as a filter dye or for various purposes such as preventing irradiation. Such dyes include
Included are oxonol dyes, hemioxonol dyes, styryl dyes, merocyanine dyes, cyanine dyes and azo dyes. Among them, oxonol dyes; hemioxonol dyes and merocyanine dyes are useful. In carrying out the present invention, the following known anti-fading agents may be used in combination, and the color image stabilizers used in the present invention may be used alone or in combination of two or more. Known antifading agents include hydroquinone derivatives, gallic acid derivatives, p-alkoxyphenols, p-oxyphenol derivatives, and bisphenols. The support used in the present invention may be paper, baryta coated paper, paper coated with an α-olefin polymer such as polyethylene, or the like. Titanium oxide, dye, etc. can be used in these supports to increase the whiteness. Preferably, a water-impermeable reflective support is used. Any known method can be used for the photographic processing of the light-sensitive material of the present invention. A known treatment liquid can be used. Processing temperature is usually 18
The temperature is selected between 18°C and 50°C, but the temperature may be lower than 18°C or above 50°C. Depending on the purpose, either a development process that forms a silver image (black and white photographic process) or a color photographic process that consists of a development process that forms a dye image can be applied. The developer used in black-and-white photographic processing can contain known developing agents. Examples of developing agents include dihydroxybenzenes (e.g. hydroquinone), 3-pyrazolidones (e.g. 1-phenyl-3-pyrazolidone), aminophenols (e.g. N-methyl-p-aminophenol), 1-phenyl-3-pyrazoline. Ascorbic acid, and heterocyclic compounds such as those described in US Pat. No. 4,067,872 in which a 1,2,3,4-tetrahydroquinoline ring and an indolene ring are condensed can be used alone or in combination.
The developing solution generally contains other well-known preservatives, alkaline agents, PH buffers, antifoggants, etc., and, if necessary, solubilizing agents, color toning agents, development accelerators, surfactants, antifoaming agents, etc. It may also contain water softeners, hardeners, viscosity-imparting agents, and the like. As the fixer, one having a commonly used composition can be used. As the fixing solution, in addition to thiosulfates and thiocyanates, organic sulfur compounds known to be effective as fixing agents can be used. The fixing solution may contain a water-soluble aluminum salt as a hardening agent. The photosensitive material of the present invention is preferably processed using an automatic processor, which enables rapid processing. At this time, the developing process is 30~45℃, 5~
It is preferable to carry out the fixing step at 30-45° C. for 5-30 seconds, and the washing step at 30-45° C. for 5-30 seconds. Further, in this case, it is preferable to use an acidic hardening fixing bath containing a polyvalent metal as the fixing bath. (Examples) Next, specific examples will be described in order to show aspects of the present invention more specifically and in detail. However, the present invention is not limited to the following examples. Example 1 Preparation of a fluorescent brightener emulsion A solution of 8 g of a fluorescent brightener in 100 ml of a high-boiling organic solvent containing chlorine atoms and 200 ml of ethyl acetate was dissolved in 800 ml of a 12% gelatin aqueous solution containing 7 g of dodecylbenzenesulfonic acid. at about 60°C and stirred vigorously with a homogenizer to prepare an emulsified dispersion. The emulsions thus prepared are shown in Table 1.

【table】

【table】

[Table] Stability of emulsion over time The emulsion of the fluorescent brightener prepared as described above was aged at 40°C, and 2 ml of the emulsion was sampled at 1000x magnification using a Nippon Kogaku microscope to observe crystallization of the emulsion. The presence or absence of was observed. Tables 3 and 4 show the number of days it takes for precipitation to be observed in 1 field of view when observing 5 fields of view.
It was as shown in the table. As can be seen from Tables 3 and 4, the emulsion using the high boiling point organic solvent of the present invention has much better emulsion dispersibility and excellent stability over time than other compounds.

【table】

【table】

[Table] Example 2 Preparation of silver halide emulsion A silver nitrate aqueous solution and a halide aqueous solution were simultaneously added and mixed into an aqueous gelatin solution at 65°C with stirring using a double jet method while controlling the pAg to form a silver iodobromide emulsion. (silver iodide content 1.2 mol%,
Average particle size 0.60μm, 86% (100) plane included14
(hedral particles). After washing and desalting this emulsion with water according to the conventional method,
Chemical sensitization was performed with sodium chloroaurate and sodium thiosulfate to obtain optimal sensitivity. Preparation of optical brightener emulsion dispersion 5 g of optical brightener was dissolved in 40 g of the high-boiling point organic solvent shown in Tables 5 and 6 and 40 ml of ethyl acetate, and 14-(4-nonylphenyl)-5, 8, 11, 14
- in a mixture of 2.5 g sodium tetraoxatetradecane sulfonate and 450 g 8.9% gelatin gel.
The mixture was added at 65 to 70°C and vigorously stirred with a homogenizer to prepare an emulsified dispersion. The silver halide emulsion prepared as described above was
Take 30 g each of 20 g of the emulsified dispersion of the optical brightener prepared as described above and potassium anhydro 9-ethyl-5,5'-dimethoxy-3,3'-bis(3-sulfopropyl)oxacarbocyanine. salt,
Surfactant compound, 0.02% solution of 5-mercapto-1-phenyltetrazole, 2-hydroxy-
4,6-dichlorotriazine sodium 2% solution,
A 10% gelatin gel and water were added, and a mixture of these was added to the support side, and a surfactant Triton X-200 (Rhom&
A gelatin coating amount of 2.25% on the emulsion layer side was prepared on a polyethylene-coated paper support by preparing an aqueous solution containing 2.25% of gelatin on the emulsion layer side, with this solution on the side far from the support.
g/m ² , gelatin coating amount on the protective layer side 1.50 g/m ² ,
They were simultaneously coated to a coating silver amount of 3.20 g/m ² and dried. The obtained sample was heated to 10 ^-6 using a xenon lamp.
The strips were subjected to second wedge exposure, developed for 18 seconds at 35° C. with the following developer, fixed, and washed with water to obtain strips with black and white finishes. The density of this strip was measured to obtain white light sensitivity and fog. The optical density of the reference point used to determine sensitivity was [fog + 0.50]. Developer composition 1-phenyl-3-pyrazolidone 0.4g Sodium sulfite 67.0g Hydroquinone 23g Potassium hydroxide 11g Sodium carbonate monohydrate 11g Potassium bromide 3g Add water 1 Fixer composition Ammonium thiosulfate 170g Sodium sulfite (anhydrous) 15g Boric acid 7g Glacial acetic acid 15ml Potassium alum 20g Ethylenediaminetetraacetic acid 0.1g Tartaric acid 3.5g Add water to make 1.

【table】

[Table] As can be seen from Table 5, the emulsified dispersion of the optical brightener using the high boiling point organic solvent of the present invention has no adverse effect on photographic sensitivity and fog. This is not unrelated to the fact that the emulsified dispersions are extremely stable as shown in Tables 3 and 4. In other words, this can be considered to be due to the fact that when a chlorinated high-boiling organic solvent is emulsified and dispersed, a fine and stable emulsion is formed, which does not cause precipitation or decomposition and does not affect photographic sensitivity or fog. Next, the above-mentioned coated sample was left unexposed and developed at 20℃ for 20 seconds using the developer and fixer described above.
Stop for 2 seconds, fix at 20°C for 20 seconds, and wash with water at 18°C for 20 seconds. The fluorescence intensity of this was measured using an 850 spectrofluorometer manufactured by Hitachi, Ltd. using excitation light with a wavelength of 400 nm. The results are shown in Table 6.

[Table] From Table 6, it can be seen that the combination of the present invention is excellent. Fluorescent brighteners F-1, F-2, F-10 are
Difficult to dissolve in high boiling point organic solvents that do not contain chlorine atoms. Compared to the case shown in Example 1, the amount of high-boiling organic solvent relative to the optical brightener was smaller, and the optical brightener was more likely to precipitate, which seems to have worsened the stability of the emulsified dispersion. . As far as the coated sample was observed under an optical microscope, no precipitation was observed, but the emulsification and dispersion using the chlorine-containing solvent of the present invention was more significant than expected than the emulsion and dispersion using the corresponding solvent that does not contain chlorine atoms. The high fluorescence intensity may be due to crystal precipitation in the latter that cannot be observed with an optical microscope, but the fluorescence intensity of a solution of these fluorescent brighteners dissolved in a chlorine-containing solvent In many cases, the fluorescence intensity is higher than that of a solution dissolved in the corresponding solvent, and this can be considered to be due to their synergistic effect. In particular, it can be seen that chlorinated paraffin is an excellent solvent for emulsifying and dispersing optical brighteners, in conjunction with the results in Tables 3 and 4. Example 3 Silver nitrate aqueous solution and halogen salt aqueous solution were added and mixed at pAg 8.7 into a gelatin aqueous solution at 50°C in the same manner as shown in Example 2, washed with water, desalted, and sulfur sensitized to remove salt odor. A silver bromide emulsion was prepared (silver bromide content
30 mol%, cubic average particle size 0.29 μm). Take 30 g each of this emulsion, add 30 g of the macenta coupler emulsion dispersion shown below, and 20 g of the optical brightener emulsion prepared by the preparation method shown in Example 1.
and further anhydro9-ethyl-5,5'-diphenyl-3,3'-bis(3-sulfopropyl)
Oxacarbocyanine sodium salt, potassium iodide 0.2% water, surfactant compound, 4-hydroxy-6-methyl-1,3,3a,7-tetrazaindene 1% solution, 2-hydroxy-4,6-dichloro An emulsion solution was prepared by adding 2% sodium triazine solution, 10% gelatin gel, and water, and a separately prepared aqueous solution containing gelatin as the main component was placed on a polyethylene laminate paper support so that this emulsion solution was on the support side. Multilayer coating was carried out in the same manner as in Example 2. This sample was wedge-exposed for 3 seconds at a color temperature of 5400 and 256 lux, and developed using the following developer. The density of the obtained strips with a magenta image was measured to obtain white light sensitivity. Separately, the fluorescence intensity was measured by the same method as shown in Example 2 for a sample which was developed with the developer described below without being exposed to light. The results obtained are shown in Table 7.

[Table] Table 7 shows that there is no adverse effect on photographic sensitivity during color development processing, and even if a small amount is applied, it is not inferior to that using a corresponding high-boiling organic solvent that does not contain chlorine atoms. do not have. On the other hand, the fluorescence intensity for improving whiteness, which is the main objective of the present invention, is clearly higher, and it can be seen that the present invention is superior. In particular, those using chlorinated paraffins No. 5 to No. 8 are superior in that their fluorescence intensity is even higher. Chlorinated paraffin also exhibits excellent effects when used in combination with other solvents. Particularly when applied to a silver halide photographic material, a phthalate ester-based high boiling point solvent is preferred as the solvent to be combined. Table 8 shows the stability over time of the optical brightener emulsion prepared using the same total amount of solvent as in Example 1 using the method shown in Example 1, and the optical brightener emulsion used. The fluorescence intensity of a sample obtained by coating and developing in the same manner as in Example 2 except that the emulsion was prepared by the above-mentioned method is shown.

[Table] As can be seen from these examples, if the technology of the present invention is used, not only can water-insoluble optical brighteners with extremely poor organic solvent properties be made into stable emulsified dispersions, but also strong fluorescent intensity can be improved by silver halide. It can be applied to photographic materials. Therefore, the whiteness, which is important especially in reflective materials, can be significantly improved. Conditions for color development processing Color development Bleaching 38°C 1 minute Washing with water 〃 6 minutes 30 seconds Fixing 〃 3 minutes 15 seconds Washing with water 〃 3 minutes 15 seconds Stability 〃 3 minutes 15 seconds Color developer composition Sodium nitrilotriacetate 1.0 g Sodium sulfite 4.0g Sodium carbonate 30.0g Potassium bromide 1.4g Hydroxylamine sulfate 2.4g 4-(N-ethyl-N-β-hydroxyethylamino)-2-methylaniline sulfate 4.5g Add water 1 Bleach Liquid composition Ammonium bromide 160.0g Ammonia water (28%) 25.0cc Ethylenediamine-tetraacetic acid sodium iron salt
130.0g Glacial acetic acid 14.0cc Add water 1 Fixer composition Sodium tetrapolyphosphate 2.0g Sodium sulfite 4.0g Ammonium thiosulfate (70%) 175.0cc Sodium bisulfite 4.6g Add water 1 Stabilizer composition Formalin 8.0cc Add water In addition 1

Claims (1)

[Claims] 1. A high boiling point organic solvent selected from compounds represented by the following general formulas -1 and -2 and chlorinated paraffin compounds, and the following general formulas (-a), (-b),
A silver halide photosensitive material characterized in that a hydrophilic colloid layer contains a water-insoluble optical brightener selected from the compounds represented by (-c) and (-d). Here, X and Y represent a hydrogen atom, an alkyl group, an alkoxy group, R ₁ , R ₂ and R ₃ represent an optionally substituted acyclic alkyl group, and m and n represent 1 or 2. However, the total number of carbon atoms in X and R ₁ is 8 or more, and the total number of carbon atoms in Y, R ₂ and R ₃ is 7 or more. Here, Y ₁ and Y ₂ are optionally substituted alkyl groups, alkoxy groups, alkoxycarbonyl groups, Z ₁
and Z ₂ is hydrogen or an optionally substituted alkyl group, n is 1 or 2, R ₁ , R ₂ , R ₃ , R ₄ , R ₅ ,
R ₆ , R ₇ , R ₈ , R ₉ , R ₁₀ and R ₁₁ are optionally substituted aryl, optionally substituted alkyl, alkoxy, aryloxy, hydroxyl, amino, cyano, carboxyl, amide, ester, alkylcarbonyl, alkyl It is a sulfo or dialkylsulfonyl group or a hydrogen atom. _R6 and _R7
is a hydrogen atom, an alkyl group such as a methyl group, an ethyl group, or a cyano group. R ₁₃ is a phenyl group,
A halogen atom or an alkyl-substituted phenyl group.
R ₁₂ is an optionally substituted alkyl group or an organic primary or secondary amine.