JPH0569421B2 - - Google Patents

Description

[Detailed description of the invention]

(A) Industrial Application Field The present invention relates to a lithographic printing plate using a silver complex diffusion transfer method suitable for using laser light, particularly semiconductor laser light, as a light source, and a method for making the same. (B) Prior art and its problems A lithographic printing plate in which a transferred silver image obtained by the silver complex diffusion transfer method can be immediately used as ink receptivity has already been published in Japanese Patent Publication No. 48-30562 and Japanese Patent Application Laid-Open No.
53-21602, 1982-103104, 1982-9750, etc., and are well known. According to a typical implementation method of the silver complex diffusion transfer method suitable for the plate making method of such a lithographic printing plate, a support is provided, and a subbing layer for preventing halation, a silver halide emulsion layer, and a physical development nucleus layer are formed on the support. When a photosensitive material consisting of is imagewise exposed and developed, the silver halide on which a latent image has been formed becomes blackened silver in the emulsion layer. At the same time, silver halide on which no latent image has been formed is dissolved by the action of a silver halide complexing agent contained in the processing solution and diffused onto the surface of the photosensitive material. The dissolved and diffused silver complex salt is deposited as a silver image on the physical development nuclei of the surface layer by the reducing action of the developing agent. The resulting silver image is subjected to development and, if necessary, a sensitization treatment to enhance its ink receptivity, and then placed in an offset printing press.
The ink image is transferred to the printed material. In conventional methods, the silver halide emulsion layer is
By merocyanine dye, cyanine dye, etc.
It was spectrally sensitized to have a maximum sensitivity in the green region around 550 nm, and exposed for several seconds to several tens of seconds using a plate-making camera with a normal light source such as a tungsten light source. However, the above-mentioned conventional method has limitations even though the lithographic printing plate originally has excellent sharpness and resolution. Moreover, if one tries to obtain color printed matter from a color original, there are still problems in that not only the resolution is insufficient, but also the production of printing plates and plate-making operations are complicated. Today, as one method for solving the above-mentioned problems, plate making using laser light has been proposed. For example, US Pat. No. 4,501,811,
Unexamined Japanese Patent Applications 1986-71055, 1983-75838, 1983-
100148 and the like disclose a lithographic printing plate for use with a helium-neon laser or a light emitting diode. As described in these patent specifications, in these lithographic printing plates using the silver complex diffusion transfer method, the surface physical development nucleus layer has a large effect on the spectral sensitization, and as a result, the desired sensitivity to laser light is achieved. In addition, as a result of forming a soft transferred deposited silver image due to silver complex salt diffusion transfer development, sharpness and resolution decrease, and furthermore, background stains may occur, and the silver image may deteriorate. It is difficult to obtain a lithographic printing plate of high quality as desired because it may come off during printing, and sufficient printing durability cannot be obtained. Therefore, it goes without saying that a sensitizing dye that satisfies these requirements has sufficiently high sensitivity at the wavelength of laser light;
It satisfies all of the following requirements: good storage stability, the ability to form a high-contrast transferred deposited silver image, no negative effects such as scumming, and the ability to form strong transferred deposited silver that cannot be removed during printing even with minute silver. It must be something that can be done. Various types of lasers are known, but
A method using a helium-neon, argon, or other laser light source as a scanner type light source provides high output, but has disadvantages 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/A/As; Ga/
Semiconductors of systems such as As; In/P; In/As are used, and the wavelength of this laser light is generally longer than 700 nm, particularly longer than 750 nm. A photosensitive lithographic printing plate using such long wavelength semiconductor laser light as a light source for imagewise exposure is described, for example, in Japanese Patent Laid-Open No. 61752/1983. This patent specifies that, in a particularly preferred embodiment, a non-silver photosensitive layer (e.g. O-
A photosensitive lithographic printing plate is shown that has a photosensitive layer made of a naphthoquinone diazide compound and a photosensitive silver halide emulsion layer, and a sensitizing dye having maximum spectral sensitivity in a wavelength region longer than 700 nm used in the emulsion layer is It is disclosed as general formulas () to (). However, according to studies conducted by the present inventors, the silver halide emulsion layer of a lithographic printing plate having a physical development nucleus layer as the outermost surface layer described above has maximum spectral sensitivity in the infrared light region with a wavelength longer than 700 nm. When containing a sensitizing dye, there are some sensitizing dyes that have relatively high sensitivity in plate making using semiconductor laser light;
Compared to conventional lithographic printing plates containing sensitizing dyes with maximum spectral sensitivity to visible light (700 nm or less), the deposited silver on the surface physical development nucleus layer is more likely to be lost during printing, resulting in lower printing durability. It turns out that there is a drawback that it cannot be used. The reason for this is not clear, but infrared sensitizing dyes have long methine chains such as pentamethine chains or heptamethine chains, and are less sensitive than visible light sensitizing dyes that have trimethine chains. Therefore, the decomposition of the sensitizing dye is promoted by the diffusion and penetration of physical development nuclei from the surface layer, and the decomposition of the sensitizing dye is desorbed from the silver halide, resulting in the formation, diffusion, and formation of complex salts of silver halide. It seems that this may have some influence on physical development. (C) Purpose of the Invention The purpose of the present invention is to provide a high-sensitivity, high-resolution,
An object of the present invention is to provide a lithographic printing plate using a silver complex diffusion transfer method that has high printing durability and is free from scumming, and a method for making the same. (D) Structure of the Invention The above object of the present invention is to provide a lithographic printing plate having at least a silver halide emulsion layer and a physical development nucleus layer as a surface layer on a support, wherein the emulsion layer has the following general formula ( ) and at least one compound represented by the following general formulas () to (). General formula ()

In the general formula (), Z ₁ and Z ₂ 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 9} 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 ₅ or R ₈ and R ₉ can also be linked to each other to form a 5- or 6-membered ring.
Y represents a sulfur atom, an oxygen atom, or N-R'(R' is an alkyl group). X represents an acid anion.
, m, n, p and q each represent 1 or 2. General formula ()

In the general formula (), Z ₃ represents an atomic group necessary to form a 5- or 6-membered nitrogen-containing heterocycle.
R ₁₀ represents an alkyl group or an alkenyl group. _R11
represents a hydrogen atom, an alkyl group, or an aryl group. X ₂ represents an acid anion, and m ₂ and n ₂ each represent 1 or 2. General formula ()

[Formula] In the general formula (), A represents a divalent directional group residue. R ₁₂ to _{R 15} are each a hydrogen atom, hydroxy group, alkyl group, alkoxy group, aryloxy group, halogen atom, heterocyclic nucleus, heterocyclylthio group, arylthio group, amino group, alkylamino group, arylamino group, heterocyclylamino group group, aralkylamino group, aryl group, and mercapto group. However, at least one of A and R ₁₂ to R ₁₅ has a sulfo group. W is-
Represents CH= or -N=. In the general formula (), 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, benzoselenazole, 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, 2-quinoline, 4-quinoline, 3,3-dialkylindolenine, imidazole, benzimidazole, naphtho[1,2-
α] Nitrogen-containing heterocycles such as imidazole and pyridine can be mentioned. 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 group, alkoxycarbonyl group, (e.g.
methoxycarbonyl, ethoxycarbonyl, etc.),
Even if it has one or more substituents such as a halogen atom (e.g., fluorine, chlorine, bromine, iodine), an aralkyl group (e.g., benzyl, phenethyl, etc.), a cyano group, an alkenyl group (e.g., allyl, etc.) good. 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, ethoxycarbonylethyl, β-ethoxycarbonylethyl, β-sulfoethyl, γ
Examples of the alkenyl group include sulfoalkyl groups such as -sulfopropyl and δ-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 9} are hydrogen atoms, halogen atoms (e.g. chlorine, bromine, iodine, fluorine), alkyl groups or aryl groups as described for R ₁ and R ₂ , or R ₁ and R ₂
It is an alkoxy group with alkyl as described in (i.e. OR ₁ group), and R ₆ and R ₅ or R ₈ and R ₉
The 5- or 6-membered ring formed by may be substituted with a lower alkyl group or the like. Examples of R' include alkyl groups such as those described for R ₁ and R ₂ . X is an acid anion such as an alkyl sulfate ion such as methyl sulfate or ethyl sulfate, a thiocyanate ion, a toluenesulfonate ion, a halogen ion such as chlorine, bromine, or iodine, or a perchlorate ion. It does not exist if . Specific examples of the sensitizing dye used in the present invention are illustrated below. (-1)

[ka] (-2)

[ka] (-3)

[ka] (-4)

[ka] (-5)

[ka] (-6)

[ka] (-7)

[ka] (-8)

[ka] (-9)

[ka] (-10)

[ka] (-11)

[ka] (-12)

[ka] (-13)

[ka] (-14)

[ka] (-15)

[ka] (-16)

[ka] (-17)

[ka] (-18)

[ka] (-19)

[ka] (-20)

[ka] (-21)

[C] In the above general formula (), Z ₃ is the general formula ()
represents an atomic group necessary to form a 5- or 6-membered nitrogen-containing heterocycle as described in Z ₁ and Z ₂ . R ₁₁ represents a hydrogen atom, an alkyl group, or an aryl group as described in the general formula (). R ₁₀ represents an alkyl group or an alkenyl group as described in the general formula (). X ₂ ^- represents an acid anion (as described for X ₁ ^- in general formula ()) and does not exist when the compound has a structure similar to betaine. m ₂ and n ₂ each represent an integer 1 or 2. Next, typical examples of compounds represented by the general formula () used in the present invention will be listed. [-1]

【formula】 [-2]

【formula】 [-3]

【formula】 [-4]

【formula】 [-5]

【formula】 [-6]

【formula】 [-7]

【formula】 [-8]

【formula】 [-9]

【formula】 [-10]

【formula】 [-11]

【formula】 [-12]

[Formula] In the above general formula (), A represents a divalent aromatic residue, and these are -SO ₃ M groups [However, M represents a hydrogen atom or a cation (e.g., sodium, potassium, etc.) . ] may be included, but
When R ₁₂ to _{R 15} do not contain -SO ₃ M, A -
It shall contain SO ₃ M group. Useful examples of A include the following. Specific example of A

【formula】

【formula】

【formula】

【formula】

[ka]

【formula】

【formula】

【formula】

[ka]

【formula】 【formula】

【formula】

【formula】

【formula】

【formula】

[Formula] R ₁₂ to _{R 15} are each a hydrogen atom, a hydroxy group,
Aryloxy groups (e.g. phenoxy, naphthoxy, O-troxy, p-sulfophenoxy, etc.),
Heterocyclic nuclei (e.g. phorforinyl, piperidyl, etc.), alkylthio groups (e.g. methylthio, ethylthio, etc.), heterocyclylthio groups (e.g. benzothiazolylthio, benzimidazolylthio, etc.),
Arylthio groups (e.g. phenylthio, tolylthio, etc.), amino groups, alkylamino groups (e.g. methylamino, ethylamino, diethylamino, β
-hydroxyethylamino, β-sulfoethylamino, etc.), arylamino groups (such as anilino,
O-, m- or p-sulfoanilino, O-, m-
or p-toluidino, O-, m- or p-carboxyanilino, O-, m- or p-chloroanilino, O-, m- or p-anisidino, O-acetaminoanilino, hydroxyanilino, naphthyl amino, sulfonaphthylamino, etc.), heterocyclylamino groups (e.g. 2-benzothiazolylamino, 2-pyridyl-amino, etc.), aralkylamino groups (e.g. benzylamino, O-, m- or p-
-anisialumino, etc.), a mercapto group, and further a halogen atom, an alkyl group, and an alkoxy group as described in R ₄ to _{R 9} of the general formula (). W is-
Represents CH= or -N=, preferably -CH=
is used. Next, typical examples of the compound represented by the general formula () used in the present invention will be shown. (-1) 4,4'-bis[4,6-di(benzothiazolyl-2-thio)pyrimidin-2-ylamino]stilbene-2,2'-disulfonic acid disodium salt (-2) 4,4'- Bis[4,6-di(benzothiazolyl-2-amino)pyrimidin-2-ylamino]stilbene-2,2'-disulfonic acid disodium salt (-3) 4,4'-bis[4,6-di(naphthyl) -2-oxy)pyrimidin-2-ylamino]stilbene-2,2'-disulfonic acid disodium salt (-4) 4,4'-bis[4,6-di(naphthyl-2-oxy)pyrimidine-2- ylamino]bibenzyl-2,2'-disulfonic acid disodium salt (-5) 4,4'-bis[4,6-dianilinopyrimidin-2-ylamino]stilbene-
2,2'-disulfonic acid disodium salt (-6) 4,4'-bis[4-chloro-6-
(2-naphthyloxy)pyrimidin-2-ylamino]biphenyl-2,2'-disulfonic acid disodium salt (-7) 4,4'-bis[4,6-di(1-phenyltetrazolyl-5) -thio)pyrimidine-
2-ylamino]stilbene-2,2'-disulfonic acid disodium salt (-8) 4,4'-bis[4,6-di(benzimidazolyl-2-thio)pyrimidin-2-ylamino]stilbene-2,2 '-Disulfonic acid disodium salt (-9) 4,4'-bis(4,6-diphenoxypyrimidin-2-ylamino)stilbene-
2,2'-disulfonic acid disodium salt (-10) 4,4'-bis(4,6-diphenylthiopyrimidin-2-ylamino)stilbene-2,2'-disulfonic acid disodium salt (-11) 4,4'-bis(4,6-dimercaptopyrimidin-2-ylamino)biphenyl-
2,2'-disulfonic acid disodium salt (-12) 4,4'-bis(4,6-dianilino-triazin-2-ylamino)stilbene-
2,2'-disulfonic acid disodium salt (-13) 4,4'-bis(4-anilino-6-
Hydroxy-triazin-2-ylamino)stilbene-2,2'-disulfonic acid disodium salt (-14) 4,4'-bis(4-naphthylamino-6-anilino-triazin-2-ylamino)stilbene-2, 2'-disulfonic acid disodium salt In order to add the sensitizing dye of the general formula [] used in the present invention to a silver halide photographic emulsion, methanol, ethanol, acetone, cellosolve, which is optionally miscible with an aqueous solution or water, can be used. , pyridine, dimethylformamide, etc., alone or as a solution in a mixed solvent. Further, these dyes may be added to the silver halide photographic emulsion at any time during the emulsion manufacturing process, but it is generally preferable to add them immediately after the completion of the second ripening. The amount added can vary within a wide range, but good results are in the range 1.times.10.sup. ^-5 to 1.times.10.sup.- ² mol per mol of silver halide. In addition, any one of the compounds represented by the general formula () and general formula () used in the present invention may be added, but two or more compounds of the general formula () may be added to the compound represented by the general formula (). Two or more compounds,
Alternatively, at least one compound of general formula () and at least one compound of general formula () may be added in combination. Which of the compounds of general formula () and the compound of general formula () is more effective in achieving the object of the present invention for the sensitizing dye of general formula () depends on the type and combination of the sensitizing dye and compound. It's different. Generally, it is advantageous to add a compound of general formula () and a compound of general formula () in combination. The amount of the compound represented by general formula () and general formula () to be added is 1 x 10 -4 to 3 x 10 -1 mol, preferably 5 x 10 ^-4 to 3 x 10 ^-1 mol, respectively, per 1 mol of silver ^halide .
It is in the range of 2×10 ⁻¹ mol. The combination of the compound represented by the general formula () and/or the general formula () with a specific infrared carbocyanine dye is disclosed in the above-mentioned JP-A-60-61752, JP-A-60-191032, and JP-A-59-192242. It is known for. However, since the lithographic printing plate of the present invention is manufactured by coating a silver halide emulsion layer and drying it, then coating a physical development nucleus layer, it is possible to avoid penetration of physical development nuclei into the silver halide emulsion layer. Therefore, it can be said that the atmosphere is extremely harsh not only immediately after production but also during storage, and in order to withstand this condition and obtain a small or small lithographic printing plate that does not deteriorate in printing durability over time. It has been found that it is optimal to use a silver halide emulsion in which a sensitizing dye represented by the general formula () is combined with a compound represented by the general formula () and/or the general formula (). Furthermore, by combining the sensitizing dye represented by the general formula () with the compound represented by the general formula () and/or the general formula (), a so-called supersensitizing effect can be obtained, resulting in high sensitivity. It turned out that it was possible to do so. The silver halide emulsion used in the present invention can be any silver halide including silver chloride, silver bromide, silver chlorobromide, and silver iodide among these. Preferably, it is a silver halide containing 60 mol% or more of silver chloride, which may contain silver iodide in a range of 0.01 to 2 mol%. The average particle size of these silver halide grains is preferably in the range of 0.2 to 0.8 microns, but ranges other than this can also be used. Furthermore, the silver halide is preferably a monodispersed emulsion in which 90% or more of the total number of grains has a grain size within ±30% of the average grain size. Although silver halide grains are preferably substantially cubic or tetradecahedral, silver halide having other crystal habits may also be used. The binder used in the silver halide emulsion of the lithographic printing plate of the present invention is usually gelatin.
Substituted with one or more hydrophilic polymer binders such as gum arabic, polyvinyl alcohol, polyvinylpyrrolidone, carboxymethyl cellulose, polyacrylamide, styrene-maleic anhydride copolymer, polyvinyl methyl ether-maleic anhydride copolymer, etc. You can also. Furthermore, an aqueous vinyl polymer dispersion (latex) can also be used. Silver halide emulsions can be sensitized in a variety of ways when they are manufactured or coated. Chemically sensitized by methods well known in the art, for example with sodium thiosulfate, alkylthioureas, or with gold compounds such as rhodan gold, gold chloride, or a combination of both. preferable. In addition, by using compounds of metals belonging to groups of the periodic table, such as salts of cobalt, nickel, rhodium, palladium, iridium, platinum, etc., at any stage in the production of silver halide emulsions, particularly high Favorable properties can be obtained by using a printing plate for direct plate making that has high sensitivity, high sharpness, and high resolution. The amount added is 10 ^-8 to 1 mole of silver halide.
It is in the range of 10 ⁻³ mol. The silver halide emulsion layer may contain other additives such as coating aids, hardeners,
It can contain conventional additives such as antifoggants, malting agents (water retention agents), and developing agents. Below the silver halide emulsion layer (on the support side), an undercoat layer is provided to improve adhesion, or an undercoat layer that may contain a coloring agent such as carbon black or a compound that absorbs light of 700 nm or more is provided. This layer can also contain a developing agent, a matting agent, and the like. The image-receiving layer is provided above the silver halide emulsion layer, that is, as the outermost surface layer. Physical development nuclei include antimony, bismuth,
cadmium, cobalt, palladium, nickel,
Known metals such as silver, lead, zinc, and their sulfides can be used. The image receiving layer contains gelatin, carboxymethyl cellulose, gum arabic, sodium alginate, hydroxyethyl starch, dialdehyde starch, dextrin, hydroxyethyl cellulose, polystyrene sulfonic acid,
It may contain one or more hydrophilic colloids such as a copolymer of vinylimidazole and acrylamide and polyvinyl alcohol. The hydrophilic colloid contained in the image-receiving layer is preferably 0.1 g/m ² or less. Hygroscopic substances such as humectants such as sorbitol, glycerol, etc. may be present in the image-receiving layer. Furthermore, the image-receiving layer contains pigments for preventing scumming such as barium sulfate, titanium dioxide, china clay, and silver, developing agents such as hydroquinone, and formaldehyde and dichloro-S-
Curing agents such as triazines may also be included. The support may be, for example, paper, film such as cellulose acetate film, polyvinyl acetal film, polystyrene film, polypropylene film, polyethylene terephthalate film, or a composite film such as polyester, polypropylene or polystyrene film coated with polyester film, metal, metallized paper, etc. Or it can be a support for a metal/paper laminate. Paper supports coated on one or both sides with an alpha-olefin polymer, such as polyethylene, are also useful. These supports may contain a compound capable of preventing halation. The DTR processing solution used in the present invention includes silver halide solvents such as sodium thiosulfate, potassium thiocyanate, cyclic imide compounds (such as uracil), and thiosalicylic acid, alkaline agents such as sodium hydroxide, potassium hydroxide, and water. Lithium oxide, trisodium phosphate, etc., preservatives, sodium sulfite, potassium sulfite, etc., thickening agents,
For example, hydroxyethyl cellulose, carboxymethyl cellulose, antifoggants such as potassium bromide, 1-phenyl-5-mercaptotetrazole, benzotriazole, compounds described in JP-A-47-26201, developers such as hydroquinone,
1-phenyl-3-pyrazolidone, a developer modifier such as a polyoxyalkylene compound, an onium compound, etc. can be included. In carrying out the silver complex diffusion transfer method, for example, British Patent No. 1000115, British Patent No. 1012476, British Patent No.
As described in specifications such as No. 1017273 and No. 1042477, a developer is mixed into the silver halide emulsion layer and/or the image receiving layer or other water permeable layer adjacent thereto. . Therefore, for such materials, the processing liquid used in the development step may be a so-called "alkaline activating liquid" which does not contain a developer. The ink receptivity of the lithographic printing plates produced according to the present invention can be changed or enhanced with compounds such as those described in Japanese Patent Publication No. 48-29723 and US Pat. No. 3,721,539. The printing method, the desensitizing liquid, the dampening liquid, etc. used can be any commonly known method. (E) Examples The present invention will be explained below with reference to examples, but it is of course not limited thereto. Example 1 A matting layer containing silica particles with an average particle size of 5 μm was provided on one side of a subbed polyester film support, and a matting layer containing silica particles with an average particle size of 5 μm was provided on the other side, and carbon black was provided on the opposite side, and 20% by weight of photographic gelatin was added to the support. An undercoat layer containing silica powder with an average particle size of 7 μm (adjusted to pH 4.5) and silica powder with an average particle size of 7 μm after being chemically sensitized with a gold compound and hypo to 5% by weight of photographic gelatin. A silver halide emulsion layer (adjusted to pH 4.5) containing the same amount of silver halide is provided. The silver halide emulsion contains 5 x 10 ^-6 mol of rhodium chloride per mol of silver halide during physical ripening, and has an average grain size of 0.4 microns, with all grains within ±30% of the average grain size. More than 90% of the particles were distributed as substantially cubic silver chloride crystals. 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 1.2 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. After drying and heating at 40°C for 14 days, the core coating liquid for plate No. 11 in Example 1 of JP-A-54-103104 was similarly prepared on top of this emulsion layer. , apply. The lithographic printing plate (sample A to H) were produced. For these samples, immediately after production (however, at 35℃)
After being stored at 50° C. and 80% relative humidity for 4 days, it was exposed to light as follows. A dark red filter (SC-70, manufactured by Fuji Photo Film Co., Ltd.) that transmits light with wavelengths longer than about 700 nm was attached to the light source, and the above-mentioned samples were exposed while being brought into close contact with the film original containing the fine line image. Flash exposure was applied in the range of 10 ^-3 to ^{10 -5} seconds depending on the sensitivity difference, so that the degree of printing was approximately the same, and this was used as a sample for printing test. On the other hand, a dark red filter (SC-70) was attached to the light source, and each sample was exposed to flash light for 10 ^-5 seconds through a light wedge to prepare samples for sensitometry. Apply each image-exposed sample to the following DTR developer []
~[V] and 25° C. for 30 seconds. After the development process, the original plate was passed between two squeezing rollers to remove excess developer, and immediately treated with a neutralizing solution having the following composition at 25°C for 20 seconds, and the excess liquid was removed using a squeezing roller. , dried at room temperature. <Transfer developer> Water 700ml Sodium hydroxide 18g Potassium hydroxide 7g Anhydrous sodium sulfite 50g Hydroquinone 13g Phenidone 1.5g 2-mercaptobenzoic acid 2g Uracil 2g 2-methylaminoethanol 30ml 5-phenyl-2-mercapto-1,3, 4-Oxadiazole 0.1g Adjust to 1 with water. <Neutralizing solution> Water 600ml Citric acid 10g Sodium citrate 35g Colloidal silica (20% liquid) 5ml Ethylene glycol 5ml Add water to bring the total volume to 1. The printing durability was determined by pasting each sample onto a single sheet, attaching this sheet to an offset printing machine, applying the following desensitizing liquid all over the plate surface, and printing using the following dampening liquid. Ivy. The printing machine used was A.B. Dick 350CD (trademark of an offset printing machine manufactured by A.B. Dick). The printing durability based on the number of sheets that could not be printed due to silver flying was evaluated according to the following criteria and is shown in Table 2. Evaluation 1 1000 sheets or less 2 1000-3000 sheets 3 3000-5000 sheets 4 5000-7000 sheets 5 7000 sheets or more <Desensitizing liquid> Water 600ml Isopropyl alcohol 400ml Ethylene glycol 50g 3-mercapto-4-acetamide-5-n -Heptyl-1,2,4-triazole 1g <Moisturizing liquid> O-phosphoric acid 10g Nickel nitrate 5g Sodium sulfite 5g Ethylene glycol 100g Colloidal silica (20% liquid) 28g Add water to make 2. The sensitivity is expressed as a relative value, with the sensitivity immediately after production of Sample A and Sample E, each containing only a dye, taken as 100, and the exposure amount required to prevent the formation of transfer deposited silver.

[Table] The amount added is per mole of silver halide (the same applies hereinafter). The results are shown in Table 2.

[Table] The results in Table 2 are for samples B~D and F~ of the present invention.
H indicates high sensitivity and shows that the drawback of decreased printing durability due to storage is improved. Example 2 A silver chloroiodobromide emulsion containing 20 mol% of silver bromide and 1.0 mol% of silver iodide was mixed with a sensitizing dye of the general formula (), a compound of the general formula (), and a sensitizing dye of the general formula () as shown in Table 3 below. Lithographic printing plates (Samples I to T) were produced according to the method of Example 1, except that the compound of formula () was added. A test was conducted in accordance with the method of Example 1, except that a transfer developer having the following formulation was used. <Transfer developer> Water 700ml Sodium hydroxide 30g Anhydrous sodium sulfite 60g Sodium thiosulfate (pentahydrate) 15g Potassium thiocyanate 10g Hydroquinone 15g Phenidone 2g Potassium bromide 1g 1-phenyl-5-mercaptotetrazole
Make 1 with 0.1g water.

【table】 The results are shown in Table 4.

【table】

Table 4 shows that similar results to Example 1 are obtained. (F) Effects of the Invention The lithographic printing plate of the present invention has high sensitivity to semiconductor laser light and high printing durability, and can reduce deterioration of these properties upon storage.

Claims (1)

[Scope of Claims] 1. In a lithographic printing plate having at least a silver halide emulsion layer and a physical development nucleus layer as a surface layer on a support, the emulsion layer is a sensitized material represented by the following general formula (). A lithographic printing plate characterized by containing at least one dye and at least one compound represented by the following general formulas () to (). General formula () [Chemical formula] (In formula (), Z ₁ and Z ₂ may be the same or different, and each represents an atomic group necessary to form a 5- or 6-membered nitrogen-containing heterocycle. represent.
R ₁ and R ₂ may be the same or different,
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 9} 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 ₅ or R ₈ and R ₉ can also be linked to each other to form a 5- or 6-membered ring. Y represents a sulfur atom, an oxygen atom, or N-R'(R' is an alkyl group). X represents an acid anion.
, m, n, p and q each represent 1 or 2. ) General formula () [Chemical formula] (In the formula (), Z ₃ represents an atomic group necessary to form a 5- or 6-membered nitrogen-containing heterocycle. R ₁₀ represents an alkyl group or an alkenyl group. R ₁₁ represents a hydrogen atom, an alkyl group, or an aryl group. X ₂ represents an acid anion, and m ₂ and n ₂ each represent 1 or 2.) General formula ()
[Formula] (In formula (), A represents a divalent directional group residue. _{R 12} to _{R 15} are each a hydrogen atom, a hydroxy group,
Alkyl group, alkoxy group, aryloxy group,
Represents a halogen atom, a heterocyclic nucleus, a heterocyclylthio group, an arylthio group, an amino group, an alkylamino group, an arylamino group, a heterocyclylamino group, an aralkylamino group, an aryl group, and a mercapto group. However, at least one of A and R ₁₂ to R ₁₅ has a sulfo group. W is -CH
= or -N=. )