JPH0551887B2 - - Google Patents

Description

[Detailed description of the invention]

(A) Industrial Application Field The present invention relates to a silver halide photographic material that is spectrally sensitized in the infrared region. (B) Prior Art and its Problems With the recent development of rapid information transmission systems, silver halide photographic materials are increasingly required to have high sensitivity. Examples include high-speed phototypesetting systems that immediately display information output from a computer as characters or graphics using a cathode ray tube, and press facsimile systems that quickly send newspaper manuscripts to remote locations. The characteristics required of silver halide photographic light-sensitive materials for such uses include so-called high-speed rays of 10 ^-4 seconds or less when using a light source such as a cathode ray tube (CRT), a laser such as helium-neon gas, or a light emitting diode (LED). It is required to have high sensitivity to short-time exposure to illuminance (referred to as flash exposure), as well as characteristics such as high contrast and high resolution. A method using a helium-neon, argon, or other laser light source as a scanner type light source provides high output, but has drawbacks such as large and expensive equipment and low power consumption efficiency. On the other hand, semiconductor lasers have advantages such as being small, inexpensive, easy to modulate, and have a long life. Semiconductor lasers include Ga/As/P; Ga/Al/As;
Semiconductors of systems such as Ga/As; In/P; In/As are used, and the wavelength of this laser light is generally longer than 700 nm, and in particular, is often longer than 750 nm. Therefore, since a bright safelight can be used, it also has the advantage of improving handling workability. However, infrared light-sensitive materials generally have problems such as insufficient sensitivity and poor storage stability, and various proposals have been made to date. For example, a technology called the so-called supersensitization effect has been proposed, in which the spectral sensitivity is significantly increased by adding a second kind of specifically selected organic compound in addition to the spectral sensitizing dye. Triazine derivatives described in Patent No. 2785058, Patent No. 3695888, etc., mercapto compounds having an electronegative group described in U.S. Patent No. 3457078, JP-A-51-
Benzotriazole derivatives described in No. 81613, quaternary salts described in JP-A-59-191032, and other JP-A No. 191032
No. 61-69063, No. 61-27884, etc. can be referred to. However, the reality is that these supersensitization techniques often give unsatisfactory results such as insufficient sensitization, increased fog, and poor storage stability. As a result of intensive research into silver halide photographic materials for use with semiconductor laser light that are free from such problems, the present inventors have found that a combination of certain compounds is extremely effective for this purpose. (C) Object of the Invention The object of the present invention is to provide a silver halide photographic material with enhanced sensitivity in the infrared region such as semiconductor lasers of 700 nm, particularly 750 nm or more. Another object of the present invention is to provide a silver halide photographic material that has no problems with fog, storage stability, etc., and has increased sensitivity in the infrared region. (D) Structure of the Invention The above object of the present invention is to provide a light-sensitive material having a silver halide emulsion layer optically sensitized with a sensitizing dye having a maximum spectral sensitivity at 700 nm or more. This was achieved by a silver halide photographic material containing at least one compound represented by the general formula (). General formula () (In the formula, R ₁ and R ₂ represent a hydrogen atom, an alkyl group, an aryl group, an aralkyl group, an alkenyl group, an amino group, an acylamido group, and a sulfonamide group, respectively, and the sum of the carbon numbers of R ₁ and R ₂ is 3 or more.) General formula () (In the formula, R ₃ represents an alkyl group or an aryl group having 3 or more carbon atoms.) Specific examples of the compound of the general formula () used in the present invention are shown below. However, only R ₁ and R ₂ in general formula () are shown.

【table】

[Table] Next, specific examples of compounds of general formula () are shown. However, only _R3 is shown.

【table】

[Table] Compounds used for comparison are shown below. (Comparison a) (Comparison b) (Comparison c) One or more of the compounds of general formula () and general formula () used in the present invention are added at any time before coating the silver halide emulsion, but in some cases, It may also be diffused from an adjacent hydrophilic colloid layer during application. The amount added is 5 per mole of silver halide, respectively.
×10 ⁻³ mmol to 5 mmol, preferably 1×
The amount ranges from 10 ^-2 mmol to 1 mmol, and the molar ratio can be arbitrarily changed within the range from 1:9 to 9:1. When adding, use a suitable solvent such as methanol, ethanol, propanol,
Advantageously, it is added as a solution in acetone, dimethylformamide or the like. Further, the compound of general formula () and the compound of general formula () may be added as one solution, or may be added as separate solutions at different times. The sensitizing dyes having maximum spectral sensitivity in the wavelength region longer than 700 nm used in the present invention are disclosed in, for example, U.S. Pat.
Same No. 3482978, Same No. 3552974, Same No. 3573921,
It can be described in the specifications of the same No. 3582344, the same No. 3623881, etc. Preferably, for example, the following general formulas () to ()
A dye represented by is used. In general formulas () to (), Z ₁ and Z ₂ are
Each may be the same or different, and each represents an atomic group necessary to form a 5- or 6-membered nitrogen-containing heterocycle. R ₁ and R ₂ may be the same or different, and each represents an alkyl group or an alkenyl group. R ₃ represents an alkyl group, an alkenyl group, or an aryl group. R ₄ to _{R 10} may be the same or different, and each represents a hydrogen atom, a halogen atom, an alkyl group, an aryl group, or an alkoxy group. However, R ₆ and R ₇ or R ₈ and R ₉ can also be linked to each other to form a 5- or 6-membered ring. R ₁₁ and R ₁₂ may be the same or different and each represents an alkyl group or an aryl group, and R ₁₁ and R ₁₂ are connected to each other to form a 5- or 6-membered
It is also possible to form a membered ring. Y is a sulfur atom,
Represents an oxygen atom, N-R ₁₃ (R ₁₃ is an alkyl group). X represents an acid anion. l, m, n, p and q each represent 1 or 2. Specific examples of Z ₁ and Z ₂ include thiazole, benzothiazole, naphtho[1,2-α]thiazole, naphtho[2,1-α]thiazole, naphtho[2,3-α]thiazole, selenazole, and benzoselenium. sol, naphtho[2,1-α]selenazole, naphtho[1,2-α]selenazole, oxazole, benzoxazole, naphtho[1,2
-α]oxazole, naphtho[2,1-α]oxazole, naphtho[2,3-α]oxazole,
Examples include nitrogen-containing heterocycles such as 2-quinoline, 4-quinoline, 3,3-dialkylindolenine, imidazole, benzimidazole, naphtho[1,2-α]imidazole, and pyridine. These heterocycles include alkyl groups (e.g. methyl,
ethyl, butyl, trifluoromethyl, etc.), aryl groups (e.g., phenyl, tolyl, etc.), hydroxy groups, alkoxy groups (e.g., methoxy, ethoxy, butoxy, etc.), carboxy groups, alkoxycarbonyl groups (e.g., methoxycarbonyl, ethoxy carbonyl, etc.), halogen atoms (e.g.
Substituents such as fluorine, chlorine, bromine, iodine), aralkyl groups (e.g., benzyl, phenethyl, etc.), cyano groups, alkenyl groups (e.g., allyl, etc.)
Alternatively, it may have two or more. In R ₁ and R ₂ , the alkyl group is methyl,
Lower alkyl groups such as ethyl, propyl, butyl,
Hydroxyalkyl groups such as β-hydroxyethyl and γ-hydroxypropyl, alkoxyalkyl groups such as β-methoxyethyl and γ-methoxypropyl, and acyloxyalkyl groups such as β-acetoxyethyl, γ-acetoxypropyl and β-benzoyloxyethyl. , carboxyalkyl groups such as carboxymethyl, β-carboxyethyl, alkoxycarbonylalkyl groups such as methoxycarbonylmethyl, ethoxycarbonylmethyl, β-ethoxycarbonylethyl, β-sulfoethyl, γ
Examples of the alkenyl group include sulfoalkyl groups such as -sulfopropyl and -sulfobutyl, aralkyl groups such as benzyl, phenethyl, and sulfobenzyl, and allyl. Examples of R ₃ include alkyl groups and alkenyl groups as described above for R ₁ and R ₂ , and aryl groups such as phenyl, tolyl, methoxyphenyl, chlorophenyl, and naphthyl. R ₄ to _{R 10} are a hydrogen atom, a halogen atom (e.g. chlorine, bromine, iodine, fluorine), an alkyl group as described for R ₁ and R ₂ , an aryl group as described for R ₁ and R ₂ It is an alkoxy group having alkyl (ie, OR ₁ group), and the 5- or 6-membered ring formed by R ₆ and R ₇ or R ₈ and R ₉ may be substituted with a lower alkyl group or the like. R ₁₁ and R ₁₂ are
R ₁ and R ₂ represent an alkyl group or an aryl group as described above, and R ₁₁ and R ₁₂ can be linked to each other to form a 5- or 6-membered ring. Examples of R ₁₃ include the alkyl groups described for R ₁ and R ₂ . Examples of the acid anion of It does not exist if . Specific examples of the sensitizing dye used in the present invention are illustrated below. The sensitizing dye used in the present invention can be synthesized by methods known to those skilled in the art. The addition to the silver halide emulsion can be at any time before the emulsion is coated, and may be before, after, or at the same time as adding the compounds of general formula () and general formula (). The amount of the sensitizing dye used in the present invention is in the range of 1 x 10 ^-6 mol to 1 x 10 ^-3 mol, preferably 5 x 10 ^-6 mol to 5 x 10 ^-4 mol, per 1 mol of silver halide. It is. Sensitizing dyes can be dispersed directly in the emulsion or dissolved in water-miscible solvents such as methanol, ethanol, pyridine, methylcellosolve, acetone, dimethylformamide, etc. (or mixtures thereof), and in some cases Dilute with water,
In some cases they can also be dissolved in water and added to the emulsion in the form of these solutions. Ultrasonic vibration can be used for this dye solution, or it can be added by the method described in US Pat. No. 3,469,987 and Japanese Patent Publication No. 46-24185. Furthermore, U.S. Patent No. 2912345,
Methods described in JP 3342605, JP 2996287, JP 3425835, etc. can also be used. The silver halide emulsion used in the present invention can be prepared by various known methods. The silver halide emulsion used in the present invention may be prepared using either a so-called single-jet method or a double-jet method, but it is preferable to use a monodisperse emulsion prepared using the latter method. is good. Further, the crystal habit of the silver halide crystal used in the present invention is cubic,
Any of octahedral, dodecahedral, and tabular crystals may be used. The halogen composition of the silver halide used in the present invention may be silver chloride, silver bromide, silver chloride, or any of these including silver iodide. During silver halide precipitation or physical ripening,
Metals such as rhodium and iridium can also be used. These emulsions can be subjected to chemical ripening by known methods. Namely, U.S. Patent No. 1574944,
No. 2278947, No. 2410689, No. 3189458, No.
Sulfur sensitization can be performed using a sulfur compound or a sensitized gelatin containing a sulfur compound as described in No. 3501313 and the like. Also, U.S. Patent No. 2597856,
Gold sensitization using gold compounds described in 2597915, 2399083, etc. can also be performed. Also, U.S. Patent No. 2518698, U.S. Patent No. 2521925, U.S. Patent No. 2487850, U.S. Patent No.
Reduction sensitization can also be performed as described in No. 2694637. These sensitization methods can be used not only alone but also in combination. The photographic emulsion used in the present invention can also be sensitized using quaternary ammonium salts, thioether compounds, polyethylene oxide derivatives, diketones, and the like. These methods are covered by U.S. Patent No.
No. 2708162, No. 3046132, No. 3046133, No.
It is described in No. 3046134, No. 3046135, British Patent No. 939357, etc. Various hydrophilic colloids are used in the photographic light-sensitive material of the present invention, and hydrophilic colloids used as vehicles for photographic emulsions and/or other photographic constituent layers include gelatin, colloidal albumin,
Cellulose derivatives such as casein, carboxymethyl cellulose, and hydroxyethyl cellulose; sugar derivatives such as agar, sodium alginate, and starch derivatives; synthetic hydrophilic colloids such as polyvinyl alcohol, polyN-vinylpyrrolidone, polyacrylic acid copolymers, and Examples include acrylamide, derivatives thereof, and partial hydrolysates. If desired, compatible mixtures of two or more of these colloids are used. The most commonly used of these is gelatin, but gelatin can be partially or completely replaced with synthetic polymeric substances, as well as so-called gelatin derivatives, i.e., amino groups as functional groups contained in the molecule. imino group,
The hydroxyl group or carboxyl group may be treated or modified with a reagent having one group capable of reacting with them, or a graft polymer to which molecular chains of other polymeric substances are bonded may be used instead. 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, glutaraldehyde, 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 (2,4-dichloro-6-hydroxy-S-triazine, etc.), mucohalogen acids (mucochloric acid, mucophenoxychloroic acid, etc.), and the like can be used alone or in combination. The photographic emulsion layer or other hydrophilic colloid layer of the light-sensitive material of the present invention may contain various surfactants for various purposes such as coating aids, antistatic properties, improving slipperiness, emulsification dispersion, and preventing adhesion. 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 Non-ionic materials such as alkylamines or amides, polyethylene oxide adducts of silicones), glycidol derivatives (e.g. alkenylsuccinic acid polyglycerides, alkylsoenol polyglycerides), fatty acid esters of polyhydric alcohols, alkyl esters of sugars, etc. Surfactant, alkyl carboxylate, alkyl sulfonate, alkylbenzene sulfonate, alkylnaphthalene sulfonate, alkyl sulfate, alkyl phosphate, N-acyl-N-alkyl taurine, sulfosucci Contains acidic groups such as carboxy groups, sulfo groups, phospho groups, sulfate ester groups, phosphate ester groups, etc., such as acid esters, sulfoalkyl polyoxyethylene alkyl phenyl ethers, polyoxyethylene alkyl phosphate esters, etc. Anionic surfactants: Amino acids, aminoalkyl sulfonic acids, aminoalkyl sulfates or phosphates, alkyl betaines, amine oxides, etc. Amphoteric surfactants: Alkylamine salts, aliphatic or aromatic quaternary ammonium salts, Cationic surfactants such as heterocyclic quaternary ammonium salts such as pyridium, imidazolium, and phosphonium or sulfonium salts containing aliphatic or heterocycles can be used. It is also possible to modify the physical properties of the gelatin film by adding latex polymers, or to make the film surface matte by adding silica, starch powder, colloidal silica, glass powder, etc. The photographic emulsion layer or other hydrophilic colloid layer of the light-sensitive material of the present invention contains the general formula described above for the purpose of preventing fog during the manufacturing process, storage or photographic processing of the light-sensitive material, or stabilizing the photographic performance. ()
Various compounds other than the compound described above can be contained. Namely, azoles such as benzothiazolium salts, nidroindazoles, triazoles, benzotriazoles, benzimidazoles (particularly nitro- or halogen-substituted):
Heterocyclic mercapto compounds, such as mercaptothiazoles, mercaptobenzothiazoles, mercaptobenzimidazoles, mercaptothiadiazoles, mercaptotetrazoles (especially 1-phenyl-5-mercaptotetrazole), mercaptopyrimidines: carboxyl groups, sulfone groups, etc. The above-mentioned heterocyclic mercapto compounds having a water-soluble group of: Thioketo compounds, such as oxazolinthione: Azaindenes, such as tetraazaindenes (particularly 4-hydroxy-substituted (1,3,3a,7) tetraazaindenes): Many compounds known as antifoggants or stabilizers can be added, such as benzenethiosulfonic acids: benzenesulfinic acid: etc. The photosensitive material of the present invention may contain various compounds other than those mentioned above, such as antistatic agents, ultraviolet absorbers, plasticizers,
A developing agent, an antihalation dye, a fluorescent dye, a development accelerator, a coupler, etc. can be used. In the photographic light-sensitive material of the present invention, any support that is normally used as a support for photographic light-sensitive materials can be used. For example, cellulose nitrate film, cellulose acetate film, cellulose acetate butyrate film, cellulose acetate propionate film, polystyrene film, polyethylene terephthalate film,
Examples include polycarbonate film, other laminates of these materials, and paper. Paper coated or laminated with baryta or α-olefin polymers, especially polymers of α-olefins having 2 to 10 carbon atoms such as polyethylene and polypropylene, Japanese Patent Publication No. 47-19068
Also suitable are supports such as plastic films whose surfaces are roughened to improve adhesion to other polymeric substances and improve printability as shown in the above-mentioned issue. Further, as a method for coating the hydrophilic colloid layer of the present invention, methods such as air doctor coating, blade coating, squeeze coating, air knife coating, reverse roll coating, cast coating, and extrusion coating are used. And the amount of application is 1~
The thickness is preferably 15 μm, more preferably 2 to 10 μm. The light-sensitive material of the present invention is useful as a black-and-white photographic light-sensitive material for semiconductor lasers, a lithographic printing plate using a silver complex diffusion transfer method, etc., but it can also be used for other purposes. (E) Examples Example 1 Using the usual controlled double jet method,
Silver chlorobromide (silver bromide 10 mol%) with an average particle size of approximately 0.23 μm
After preparing an emulsion, precipitating it, washing it with water and redissolving it, the ratio of gelatin to silver was adjusted to 0.6 to 1.0, and it was sensitized with sulfur and gold.
After completion of the reaction, 1×10 ^-4 mol of exemplified dye (10) was added as a sensitizing dye per mol of silver halide, and a hardening agent and a surfactant were added. This emulsion was divided into equal parts and the compounds shown in Table 1 were added to prepare a finished emulsion. A sample was prepared by coating these emulsions together with a protective layer (gelatin 1 g/m ² ) on a polyester film in a layered manner so that the silver concentration was 6 g/m ² . These samples were subjected to sensitometric exposure for 10 ^-5 seconds through a 780 nm interference filter.
It was developed with PQ developer, fixed, washed with water, and dried to determine its characteristics. The results are shown in Table 1. Sensitivity is sample 1
It is expressed as a relative value with 100. The amount added is the amount (mg) per mole of silver halide.

Table 1 shows that Sample 6 of the present invention has high sensitivity and low fog. Example 2 Silver iodobromide containing 2 mol% silver iodide (average grain size 0.3 μm)
Example 1 was followed except that an emulsion was used and the compounds shown in Table 2 were added.

【table】

[Table] The results in Table 2 show that Samples 24 to 29 of the present invention have high sensitivity and low fog, similar to Example 1. Example 3 A support coated on both sides with polyethylene resin was provided with a matting layer containing silica particles with an average particle size of 5 μm on one side, and a mattifying layer containing carbon black and phenidone on the other side, with a 20% concentration relative to photographic gelatin. An undercoat layer (adjusted to pH 4.5) containing silica powder with an average particle size of 7 μm in weight percent, and after chemical sensitization with gold compound and hypo, 2-mercaptobenzoic acid and silica powder with an average particle size of 7 μm. A silver halide emulsion layer (adjusted to pH 4.5) containing 5% by weight of photographic gelatin is provided. The silver halide emulsion contains sensitizing dye (13) in an amount of 1.0 x 10 ^-4 mol per mol of silver halide, and 5 x 10 ^-7 mol of iridium per mol of silver halide is added during physical ripening. The average particle size
They were substantially cubic silver chloride crystals with a diameter of 0.42 microns, with more than 90% of the total grains distributed within a range of ±30% of the average grain size. Gelatin for the undercoat layer was coated at a rate of 3.0 g/m ² , gelatin for the emulsion layer was coated at a rate of 1.0 g/m ² , and silver halide was coated at a rate of 1.0 g/m ² in terms of silver nitrate. The undercoat layer and emulsion layer contain formalin as a hardening agent in an amount of 5.0 mg/g gelatin. The optical reflection density of the undercoat layer at 780 nm is 0.83
It was hot. After drying and heating at 40°C for 14 days, 0.8 g/m of hydroquinone was added to the core coating liquid of plate No. 11 in Example 1 of JP-A-54-103104. ² was prepared in the same manner and applied (comparative lithographic printing plate A). Six types of lithographic printing plates were similarly prepared by adding the compounds shown in Table 3 to the silver halide emulsion of comparative lithographic printing plate A. A dark red filter that transmits light with a wavelength longer than about 700 nm was attached to the light source, and each lithographic printing plate was exposed for 10 ^-5 seconds through a wedge with a density difference of 0.15. Each printing plate was then developed with a known DTR developer,
Treated with acidic neutralizing solution. The results are shown in Table 3.

[Table] On the other hand, determine the appropriate exposure according to the sensitivity of each lithographic printing plate.
It was provided using an Ultre Setter (manufactured by Ultre, USA), a laser diode scanner that emits light at 780 nm. Thereafter, when developed, neutralized, plate-made, and printed in the same manner, the lithographic printing plates F and G of the present invention were obtained.
It had better printing durability than the comparative lithographic printing plate. Example 4 The same procedure as in Example 3 was carried out except that exemplified dye (15), (23) or (28) was used instead of exemplified dye (13).
Similar results to Example 3 were obtained. (F) Effects of the Invention According to the present invention, the sensitivity of a sensitizing dye having maximum spectral sensitivity in the infrared region of 700 nm, especially 750 nm or more can be increased by combining specific mercapto compounds, and fog can be reduced. Therefore, a highly sensitive silver halide photographic material suitable for semiconductor lasers can be obtained.

Claims (1)

[Scope of Claims] 1. A light-sensitive material having a silver halide emulsion layer optically sensitized with a sensitizing dye having a maximum spectral sensitivity at 700 nm or more, in which the emulsion layer has a compound represented by the following general formula () and general formula (). 1. A silver halide photographic material containing at least one compound. General formula () (In the formula, R ₁ and R ₂ represent a hydrogen atom, an alkyl group, an aryl group, an aralkyl group, an alkenyl group, an amino group, an acylamido group, and a sulfonamide group, respectively, and the sum of the carbon numbers of R ₁ and R ₂ is 3 or more.) General formula () (In the formula, R ₃ represents an alkyl group or an aryl group having 3 or more carbon atoms.)