JP2003084452A - Alkali developing solution for planographic printing plate and method for making planographic printing plate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an alkali developing solution for a planographic printing plate which suppresses generation of insoluble matter due to a binder resin and an IR absorbent and deposition on a plate surface while retaining the liquid conditions of the alkali developing solution and enables long-term stable development and to provide a method for making a planographic printing plate. SOLUTION: The alkali developing solution for an IR sensitive planographic printing plate contains a soy polysaccharide. In the method for making a planographic printing plate, an IR sensitive planographic printing plate having an image forming layer containing an IR absorbent is exposed with IR and developed with the alkali developing solution.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a development processing solution for alkaline development of a so-called direct plate-making lithographic printing plate precursor which can be directly plate-formed by infrared laser scanning based on a digital signal from a computer or the like. The present invention further relates to a method for making a lithographic printing plate using this alkaline development processing solution.

[0002]

2. Description of the Related Art In recent years, the development of lasers has been remarkable, and in particular, solid-state lasers and semiconductor lasers having a near-infrared to infrared emission region have been easily available with high output and small size. These lasers are very useful as an exposure light source for a system for making a plate directly from this digital data.

As an image recording material suitable for laser writing, for example, JP-A-7-285275 discloses a binder such as a cresol resin, a substance which absorbs light to generate heat, and a quinonediazide. A positive image recording material has been proposed which contains a compound that is thermally decomposable and that can substantially reduce the solubility of the binder in the state before decomposition. This is due to infrared irradiation
In the exposed part, the substance that absorbs the light to generate heat generates heat and makes the exposed part alkali-soluble (heat mode type), but the thermal efficiency is low because it is absorbed by the aluminum support. However, the solubility in the alkaline developing solution in the developing step was not satisfactory. Therefore, the alkali concentration of the developer has been increased to ensure the solubility of the exposed portion.

However, the heat mode type lithographic printing plate precursor has a low resistance to dissolution in the alkali developing solution in the image area under the above-mentioned high-concentration alkaline conditions, and the surface of the image recording material is slightly scratched. However, there is a problem that it is melted by a certain amount, and defects are likely to occur particularly in the image portion such as a thin line. Further, with the improvement of infrared laser exposure type image recording materials, there is a tendency that an infrared absorbing agent which is hardly dissolved in an alkali developing solution is used as compared with a conventional infrared absorbing dye using o-quinonediazide. When the image recording material is developed with an alkali developing treatment solution, insoluble matter of the infrared absorbing dye is discharged into the treatment solution, and further, it interacts with the components of the binder polymer and inorganic substances in water. To form insoluble matter, and these adhere to the plate during the development process during plate making, which disturbs the image, and it is necessary to remove precipitated insoluble matter on a regular basis. It caused a great burden on maintenance.

[0005]

SUMMARY OF THE INVENTION It is an object of the present invention to solve various problems in the prior art and achieve the following objects. That is, the present invention, while maintaining the liquid conditions of the alkaline development processing solution, suppresses the generation of insoluble matter due to the binder resin or the infrared absorber or the like and the adhesion to the plate surface, and enables stable development for a long period of time. It is an object of the present invention to provide an alkaline developing treatment solution for a lithographic printing plate which can be used, and also to provide a method for making a lithographic printing plate.

[0006]

The present inventors have developed an infrared-sensitive lithographic printing plate having an image-forming layer containing an infrared absorber using an alkaline developing solution containing soybean polysaccharide. Suppresses the generation of the insoluble matter,
In addition, it was found that adhesion and precipitation of insoluble matter can be prevented,
The present invention has been completed. Therefore, the present invention relates to an infrared developing processing solution for an infrared-sensitive lithographic printing plate, which contains soybean polysaccharide. The present invention further relates to a method of making a lithographic printing plate, which comprises exposing an infrared-sensitive lithographic printing plate having an image-forming layer containing an infrared absorber to infrared radiation and then developing it with the above alkaline developing solution.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION The alkaline developing treatment solution for a lithographic printing plate of the present invention contains soybean polysaccharide and further contains other components. INDUSTRIAL APPLICABILITY The alkaline developing treatment solution and plate-making method of the present invention can be applied to the developing treatment of any photosensitive lithographic printing plate having an image forming layer containing an infrared absorber.

First, the alkaline developing solution used for developing the planographic printing plate will be described. The alkaline developing solution used for the developing treatment (hereinafter, may be simply referred to as “developing solution”) is an alkaline aqueous solution, and can be appropriately selected from conventionally known alkaline aqueous solutions. Examples of the alkaline aqueous solution include a developing solution containing an alkali silicate or non-reducing sugar and a base, and a solution having a pH of 12.5 to 14.0 is particularly preferable. The alkali silicate shows alkalinity when dissolved in water, and examples thereof include alkali metal silicates such as sodium silicate, potassium silicate, and lithium silicate, and ammonium silicate. The alkali silicate may be used alone or in combination of two or more.

The alkaline aqueous solution contains silicon oxide SiO ₂ which is a component of silicate and alkali oxide M ₂ O (M is
Represents an alkali metal or ammonium group. ), The developing property can be easily adjusted by adjusting the mixing ratio and the concentration. Among the alkaline aqueous solutions, the mixing ratio of the silicon oxide SiO ₂ and the alkali oxide M ₂ O (Si
The O ₂ / M ₂ O: molar ratio) is preferably 0.5 to 3.0, more preferably 1.0 to 2.0. SiO
_{When 2} / M ₂ O is less than 0.5, the alkali strength increases, which may cause an adverse effect of etching a general-purpose aluminum plate or the like as a support for a lithographic printing original plate. If it exceeds 3.0, the developability may decrease.

The concentration of the alkali silicate in the developer is 1 to 10% by mass with respect to the mass of the alkaline aqueous solution.
Is preferable, 3-8 mass% is more preferable, 4-7 mass% is the most preferable. If the concentration is less than 1% by mass, developability and processing power may decrease, and the content may be 10% by mass.
If it exceeds, the precipitates and crystals are likely to be generated, and further, gelation is likely to occur during neutralization during the waste liquid, which may hinder the waste liquid treatment.

In the developer containing the non-reducing sugar and the base, the non-reducing sugar means a saccharide having no reducing property because it does not have a free aldehyde group or a ketone group. It is classified into a bound trehalose-type oligosaccharide, a glycoside in which a reducing group of a saccharide and a non-saccharide are bound, and a sugar alcohol reduced by hydrogenating a saccharide. In the present invention, any of these can be preferably used.

Examples of the trehalose-type oligosaccharides include saccharose and trehalose, and examples of the glycosides include alkyl glycosides, phenol glycosides, mustard oil glycosides and the like. Examples of the sugar alcohol include D, L-arabite, rebit, xylit, D, L-sorbit, D, L-mannite,
Examples thereof include D, L-idit, D, L-talit, zuricit, and alodulcit. Furthermore, preferable examples include rutitol obtained by hydrogenation of disaccharides and a reduced form (reduced starch syrup) obtained by hydrogenation of oligosaccharides.

Among the above, as the non-reducing sugar, sugar alcohol and saccharose are preferable, and among them, D-sorbit, sucrose and reduced starch syrup are more preferable because they have a buffering action in an appropriate pH range. These non-reducing sugars may be used alone or in combination of two or more, and the proportion in the developer is preferably 0.1 to 30% by weight,
1 to 20% by weight is more preferable.

The alkali silicate or non-reducing sugar can be combined with an alkali agent as a base, which is appropriately selected from those conventionally known. Examples of the alkaline agent include sodium hydroxide, potassium hydroxide,
Lithium hydroxide, trisodium phosphate, tripotassium phosphate, triammonium phosphate, disodium phosphate, dipotassium phosphate, diammonium phosphate, sodium carbonate, potassium carbonate, ammonium carbonate, sodium hydrogen carbonate, potassium hydrogen carbonate Inorganic alkaline agents such as ammonium hydrogen carbonate, sodium borate, potassium borate, and ammonium borate, potassium citrate, tripotassium citrate, sodium citrate, and the like. Furthermore, monomethylamine, dimethylamine, trimethylamine,
Monoethylamine, diethylamine, triethylamine, monoisopropylamine, diisopropylamine,
Organic alkali agents such as triisopropylamine, n-butylamine, monoethanolamine, diethanolamine, triethanolamine, monoisopropanolamine, diisopropanolamine, ethyleneimine, ethylenediamine, and pyridine can also be preferably mentioned. These alkaline agents may be used alone or in combination of two or more kinds.

Of these, sodium hydroxide and potassium hydroxide are preferred. The reason is that the pH can be adjusted in a wide pH range by adjusting the addition amount to the non-reducing sugar. In addition, trisodium phosphate, tripotassium phosphate, sodium carbonate, potassium carbonate and the like are preferable because they have a buffering effect.

In the alkaline developing solution of the present invention,
Soybean polysaccharide is contained in the alkaline aqueous solution as described above. More specifically, the soybean polysaccharide used in the present invention is a water-soluble soybean polysaccharide having a film-forming property. Water-soluble soybean polysaccharide is a polysaccharide obtained by extracting raw soybean with water,
It mainly contains galactose, arabinose, and galacturonic acid as constituent components. Examples of commercially available products include Soyafive-S-DN and Soyafive-S-LN (both manufactured by Fuji Oil Co., Ltd.). The soybean polysaccharide which can be used in the present invention preferably has an average molecular weight of 5 to 1,000,000 and a 10% by mass aqueous solution having a viscosity (25 ° C.) of 5 to 100 cp. These soybean polysaccharides are dissolved in water or warm water and used as a uniform aqueous solution. The content of soybean polysaccharide in the alkali developing solution is 0.001 to 1
0.0 mass% is suitable, and preferably 0.01 to
It is 5.0% by mass, more preferably 0.1 to 1.0% by mass. If it is less than 0.001% by mass, it is difficult to protect the non-image area to maintain hydrophilicity, while if it exceeds 10.0% by mass, it may not be dissolved in the developer and may be deposited.

As described above, the alkaline developing treatment solution of the present invention uses a developing solution containing an alkali silicate or non-reducing sugar and a base.
i ⁺ , Na ⁺ , K ⁺ , and NH ₄ ⁺ are used. Among them, in a system containing a large number of cations having a small ionic radius, the penetrability into the image forming layer is high and the developability is excellent, but the image area is also dissolved. Cause image defects. Therefore, there is a certain limit to increase the alkali concentration, and in order to completely process the image forming layer (residual film) in the non-image area without causing a defect in the image area, it is a delicate matter. It was required to set various liquid conditions. However, as the cation component,
By using a cation with a large ionic radius,
The permeability of the developing solution into the image forming layer can be suppressed, and the dissolution inhibiting effect of the image area can be improved without lowering the alkali concentration, that is, the developability. As the cation component, other cations can be used in addition to the above-mentioned alkali metal cations and ammonium ions.

A surfactant can be further added to the alkaline developing treatment liquid of the present invention. Examples of the surfactant include nonionic surfactants, anionic surfactants, cationic surfactants and amphoteric surfactants. As the nonionic surfactant, polyoxyethylene alkyl ethers, polyoxyethylene alkylphenyl ethers, polyoxyethylene polystyryl phenyl ethers, polyoxyethylene polyoxypropylene alkyl ethers, glycerin fatty acid partial esters,
Sorbitan fatty acid partial esters, pentaerythritol fatty acid partial esters, propylene glycol monofatty acid esters,

Sucrose fatty acid partial esters, polyoxyethylene sorbitan fatty acid partial esters, polyoxyethylene sorbitol fatty acid partial esters, polyethylene glycol fatty acid esters, polyglycerin fatty acid partial esters, polyoxyethylenated castor oils,
Polyoxyethylene glycerin fatty acid partial esters,
Suitable examples include fatty acid diethanolamides, N, N-bis-2-hydroxyalkylamines, polyoxyethylene alkylamines, triethanolamine fatty acid esters, and trialkylamine oxides.

Examples of the anionic surfactant include fatty acid salts, abietic acid salts, hydroxyalkanesulfonic acid salts, alkanesulfonic acid salts, dialkylsulfosuccinic acid ester salts, α-olefinsulfonic acid salts, linear alkylbenzenesulfonic acid salts, and branched salts. Chain alkylbenzene sulfonates, alkylnaphthalene sulfonates, alkylphenoxy polyoxyethylene propyl sulfonates, polyoxyethylene alkyl sulfophenyl ether salts, N-methyl-N-oleyl taurine sodium salt, N-alkyl sulfosuccinic acid monoamide Sodium salt, petroleum sulfonates, sulfated tallow oil,
Sulfate ester salts of fatty acid alkyl esters, alkyl sulfate ester salts, polyoxyethylene alkyl ether sulfate ester salts,

Fatty acid monoglyceride sulfate ester salts,
Polyoxyethylene alkyl phenyl ether sulfate ester salts, polyoxyethylene styryl phenyl ether sulfate ester salts, alkyl phosphate ester salts, polyoxyethylene alkyl ether phosphate ester salts, polyoxyethylene alkyl phenyl ether phosphate ester salts, styrene / anhydrous Preferable examples include partially saponified products of maleic acid copolymers, partially saponified products of olefin / maleic anhydride copolymers, and naphthalenesulfonate formalin condensates.

Examples of the cationic surfactant include alkylamine salts, quaternary ammonium salts such as tetrabutylammonium bromide, polyoxyethylene alkylamine salts and polyethylene polyamine derivatives. Examples of the amphoteric surfactant include carboxybetaines, alkylaminocarboxylic acids, sulfobetaines, aminosulfates, imidazolines and the like. Among the above surfactants, those with "polyoxyethylene" can be read as polyoxyalkylenes such as polyoxymethylene, polyoxypropylene and polyoxybutylene, and these are also included in the above surfactants. It The surfactant concentration in the developer is preferably 0.001 to 10.0% by mass,
0.01-5.0 mass% is more preferable, and 0.1-1.
Most preferred is 0% by weight.

The following additives may be added to the alkaline developing solution for the purpose of further improving the developing performance. For example, N described in JP-A-58-75152
Neutral salts such as aCl, KCl and KBr, JP-A-58-1
Chelating agents such as EDTA and NTA described in JP-A-90952, and [C described in JP-A-59-121336].
complexes such as o (NH ₃ ) ₆ ] Cl ₃ , CoCl ₂ .6H ₂ O, sodium alkylnaphthalenesulfonate described in JP-A No. 50-51324, and n-tetradecyl-N, N.
-Anionic or amphoteric surfactants such as dihydroxyethyl betaine, nonionic surfactants such as tetramethyldecynediol described in US Pat. No. 4,374,920, described in JP-A-55-95946. P-
Cationic polymers such as methyl chloride quaternary compounds of dimethylaminomethyl polystyrene, JP-A-56-
An amphoteric polymer electrolyte such as a copolymer of vinylbenzyltrimethylammonium chloride and sodium acrylate described in JP-A-142528, JP-A-57-192951.
Inorganic lithium compounds such as lithium chloride described in JP-A-58-59444, organic Si, Ti described in JP-A-59-75255, and the like. Including organometallic surfactants,
Examples thereof include organic boron compounds described in JP-A-59-84241, and quaternary ammonium salts such as tetraalkylammonium oxide described in EP101010.

The mode of use of the alkaline development processing solution of the present invention is not particularly limited. In recent years, especially in the platemaking and printing industry, to streamline and standardize platemaking work,
Automatic developing machines for printing plate materials are widely used. This automatic developing machine is generally composed of a developing section and a post-processing section, and is composed of a device for conveying a printing plate material, each processing liquid tank, and a spray device. Each of the processing liquids pumped up is sprayed from a spray nozzle for development processing. Further, recently, a method has also been known in which a printing plate material is immersed and conveyed by a submerged guide roll or the like in a treatment liquid tank filled with the treatment liquid to perform treatment.
In such automatic processing, it is possible to perform processing while replenishing each processing solution with a replenishing solution according to the processing amount, operating time, and the like.

In this case, a large amount of the image forming material can be processed without replacing the developing solution in the developing tank for a long time by adding an aqueous solution having a higher alkali strength than the developing solution as a replenishing solution to the developing solution. It is a preferred embodiment to employ this replenishment method even when the alkaline developing treatment solution of the present invention is used. Also as the replenisher, the alkaline developing treatment liquid for a lithographic printing plate of the present invention can be used as an aqueous solution having a higher alkaline strength than the developing liquid for development.

The above-mentioned developing solution and developing solution replenishing solution may contain various surface active agents other than those mentioned above, if necessary, for the purpose of accelerating or suppressing the developing property, dispersing the development residue and enhancing the ink affinity of the printing plate image area. Agents and organic solvents can also be added. The surfactant can be selected from anionic, nonionic, cationic or amphoteric surfactants, and the organic solvent is preferably benzyl alcohol. It is also preferable to add polyethylene glycol or its derivative, or polypropylene glycol or its derivative. Further, if necessary, an inorganic salt-based reducing agent such as hydroquinone, resorcinol, sodium salt or potassium salt of sulfurous acid or bisulfite, an organic carboxylic acid, an antifoaming agent, and a water softener may be added.

The lithographic printing plate developed using the alkaline developing solution and the replenisher of the present invention is a rinsing solution containing washing water and a surfactant, and a desensitizing solution containing gum arabic and a starch derivative. Post-processing is done. This post-treatment can be performed by combining these treatment liquids in various ways. Further, it is also possible to adopt a so-called disposable processing method in which processing is carried out with a substantially unused developing processing solution.

Next, the planographic printing plate precursor used in the planographic printing plate making method of the present invention will be described. The infrared-sensitive lithographic printing plate has an image forming layer on a support and, if necessary, further other layers, and the image forming layer is (A).
Infrared absorbing agent, further containing (B) alkali-soluble polymer compound, in addition to (C) an alkali-soluble polymer compound is compatibilized to reduce the solubility of the alkali-soluble polymer compound in an alkaline aqueous solution, The compound which decreases the solubility-decreasing effect by the above, (D) cyclic acid anhydride and the like may be contained. In the case of a negative type lithographic printing plate precursor, the exposed area is cured to form an image area.
(F) A cross-linking agent that cross-links with an acid. Hereinafter, each component will be briefly described.

-(A) Infrared absorbing agent-The infrared absorbing agent (hereinafter sometimes referred to as "(A)" component ") has a function of converting absorbed infrared rays into heat. As the usable infrared absorbing agent, a dye or pigment capable of absorbing infrared rays in a wavelength range of 700 nm or more, preferably in a wavelength range of 750 nm to 1200 nm with high efficiency is preferable, and an absorption maximum in a wavelength range of 760 nm to 1200 nm. More preferred are dyes or pigments having.

Examples of the dye material include commercially available dyes and known dyes described in the literature (for example, "Handbook of Dyes", edited by The Society of Synthetic Organic Chemistry, published in 1945). For example, azo dyes and metal complex salt azo. Examples thereof include dyes, pyrazolone azo dyes, naphthoquinone dyes, anthraquinone dyes, phthalocyanine dyes, carbonium dyes, quinonimine dyes, methine dyes, cyanine dyes, squarylium dyes, pyrylium salts, and metal thiolate complexes.

Among them, for example, JP-A-58-12524.
6, JP-A-59-84356, JP-A-59-202.
829, cyanine dyes described in JP-A-60-78787, JP-A-58-173696, JP-A-58-1.
81690, methine dyes described in JP-A-58-194595, JP-A-58-112793, and JP-A-58.
-224793, JP-A-59-48187, JP-A-59-73996, JP-A-60-52940, JP-A-60-63744, and the like, naphthoquinone dyes, JP-A-58-112792, and the like. Preferable examples thereof include the squarylium dye described in JP-A No. 434,875, the cyanine dye described in British Patent 434,875, and the dihydroperimidine squarylium dye described in US Pat. No. 5,380,635.

The near-infrared absorption sensitizers described in US Pat. No. 5,156,938 are also preferable, and the substituted arylbenzo (thio groups described in US Pat. No. 3,881,924 are also preferable. ) Pyrylium salt, JP-A-57-1426
45 (US Pat. No. 4,327,169), a trimethine thiapyrylium salt, JP-A-58-1810.
No. 51, No. 58-220143, No. 59-41363.
No. 59-84248, No. 59-84249, No. 59-146063, No. 59-146061, cyanine dyes described in JP-A No. 59-216146, U.S. Pat. No. 283,475, pentamethine thiopyrium salt, etc., Japanese Patent Publication Nos. 5-13514 and 5-19702, pyrilium compounds, and commercially available products, Epolight III-178, E
polight III-130, Epolight III-125, Epolight
IV-62A (manufactured by Eporin) and the like are also preferable.

Further, near-infrared absorbing dyes represented by the formulas (I) and (II) described in US Pat. No. 4,756,993 can also be mentioned as preferable ones. Among the above, a cyanine dye, a squarylium dye, a pyrylium salt, and a nickel thiolate complex are more preferable.

As the above-mentioned pigments, commercially available pigments or color index (CI) handbook, "Latest pigment handbook" (edited by Japan Pigment Technology Association), 1977), "Latest pigment application technology" (CMC Publishing, 1986) Annually), "Printing Ink Technology" (CMC Publishing, 1984), and examples thereof include black pigments, yellow pigments, orange pigments, brown pigments, red pigments, purple pigments, blue pigments, green pigments, Fluorescent pigments, metal powder pigments, and other polymer-bonded dyes may be mentioned.

Specifically, for example, insoluble azo pigments, azo lake pigments, condensed azo pigments, chelate azo pigments, phthalocinanine pigments, anthraquinone pigments, perylene and perinone pigments, thioindigo pigments, quinacridone pigments, dioxazine pigments, Isoindolinone pigment, quinophthalone pigment, dyed lake pigment, azine pigment, nitroso pigment, nitro pigment, natural pigment, fluorescent pigment,
Examples include inorganic pigments and carbon black. Above all,
Carbon black is preferred.

The pigment may be used without surface treatment, or may be used after surface treatment. As a method of surface treatment, a method of surface coating resin or wax,
Examples thereof include a method of attaching a surfactant and a method of binding a reactive substance (for example, a silane coupling agent, an epoxy compound, polyisocyanate, etc.) to the pigment surface.
The method of these surface treatments is "property and application of metallic soap".
(Koshobo), "Printing ink technology" (CMC Publishing, 198)
4 years) and "Latest pigment application technology" (CMC Publishing, 19
1986).

The particle size of the pigment is 0.01 μm to 1
0 μm is preferable, 0.05 μm to 1 μm is more preferable, and 0.1 μm to 1 μm is most preferable. The particle size is 0.
If it is less than 01 μm, the stability of the dispersion when the dispersion such as the photosensitive layer coating solution is prepared may deteriorate.
When it exceeds μm, the uniformity of the image forming layer may deteriorate.

The method for dispersing the pigment can be appropriately selected from known dispersing techniques such as a general-purpose disperser for ink production and toner production. Examples of the disperser include an ultrasonic disperser, a sand mill, an attritor, a pearl mill, a super mill, a ball mill, an impeller, a desperzer,
A KD mill, a colloid mill, a dynatron, a three roll mill, a pressure kneader and the like can be mentioned. The details are described in "Latest Pigment Application Technology" (CMC Publishing, 1986).

The content of the dye or pigment is preferably 0.01 to 50% by mass, more preferably 0.1 to 10% by mass, more preferably 0.1 to 10% by mass, based on the total mass of the solid content of the image forming layer. Is most preferably 0.5 to 10% by mass, and in the case of a pigment, 3.1 to 10% by mass is most preferable. If the content is less than 0.01% by mass, the sensitivity may be lowered, and if it exceeds 50% by mass, the uniformity of the image forming layer may be deteriorated and the durability thereof may be deteriorated.

The dye or pigment may be added to the same layer as other components, or may be added to another layer provided separately. When it is formed as another layer, it is preferably added to a layer adjacent to the layer containing the component (C) described later. Further, the dye or pigment and the alkali-soluble polymer compound are preferably contained in the same layer, but may be contained in different layers.

-(B) Alkali-soluble polymer compound-A usable alkali-soluble polymer compound (hereinafter,
Sometimes referred to as "(B) component". As the above), an alkaline water-soluble polymer compound having the following acidic groups (1) to (3) in the main chain and / or side chain structure can be used. (1) phenol group (-Ar-OH) (2) sulfonamide group _{(-SO 2 NH-R) (} 3) substituted sulfonamide-based acid group [(hereinafter, referred to as "active imide group".) - SO ₂ NHCOR , -SO ₂ NHSO
₂ R, —CONHSO ₂ R] In the above (1) to (3), Ar represents a divalent aryl linking group which may have a substituent, and R may have a substituent. Represents a hydrocarbon group. Specific examples thereof are shown below, but the present invention is not limited thereto.

(1) Examples of the alkali-soluble polymer compound having a phenol group include a condensation polymer of phenol and formaldehyde, a condensation polymer of m-cresol and formaldehyde, and a condensation polymer of p-cresol and formaldehyde. , A condensation polymer of m- / p-mixed cresol and formaldehyde, phenol and cresol (m
Any of-, p- or m- / p- mixture may be used. A novolak resin such as a condensation polymer of) and formaldehyde, or a condensation polymer of pyrogallol and acetone. Further, a polymer compound obtained by polymerizing a monomer having a phenol group in its side chain can also be mentioned.

As the polymer compound having a phenolic hydroxyl group in the side chain, a polymerizable monomer consisting of a low molecular weight compound having one or more unsaturated bonds capable of polymerizing with the phenolic hydroxyl group is homopolymerized, or Examples thereof include polymer compounds obtained by copolymerizing a monomer with another polymerizable monomer. Examples of the monomer having a phenol group in its side chain include acrylamide, methacrylamide, acrylic acid ester, methacrylic acid ester, hydroxystyrene and the like having a phenol group in its side chain.

Specifically, N- (2-hydroxyphenyl) acrylamide, N- (3-hydroxyphenyl)
Acrylamide, N- (4-hydroxyphenyl) acrylamide, N- (2-hydroxyphenyl) methacrylamide, N- (3-hydroxyphenyl) methacrylamide, N- (4-hydroxyphenyl) methacrylamide, o-hydroxyphenyl acrylate , M-hydroxyphenyl acrylate, p-hydroxyphenyl acrylate, o-hydroxyphenyl methacrylate, m-hydroxyphenyl methacrylate, p-hydroxyphenyl methacrylate, o-hydroxystyrene, m-hydroxystyrene, p-hydroxystyrene, 2- (2 -Hydroxyphenyl) ethyl acrylate, 2- (3-hydroxyphenyl) ethyl acrylate, 2- (4-hydroxyphenyl) ethyl acrylate, 2- (2-hydro) Shifeniru) ethyl methacrylate, 2- (3-hydroxyphenyl) ethyl methacrylate, 2- (4-hydroxyphenyl) ethyl methacrylate can be preferably exemplified.

Alkali-soluble having the above-mentioned phenol group
The weight average molecular weight of the polymer compound is 5.0 × 10.²
~ 2.0 x 10^FiveHas a number average molecular weight of 2.0.
× 10 ²~ 1.0 x 10^FiveAre preferable in terms of image forming property.
Good In addition, the alkali-soluble high content of phenol group
Sub-compounds can be used alone or in combination of two or more.
You may use together. If you want to combine,
As described in U.S. Pat. No. 4,123,279,
Condensation polymer of t-butylphenol and formaldehyde
And polycondensation of octylphenol and formaldehyde
Body-like alkyl group having 3 to 8 carbon atoms as a substituent
The condensation polymer of phenol and formaldehyde
May be used. These polycondensates also have a weight average molecular weight of
5.0 x 10²~ 2.0 x 10^FiveHaving a number average molecular weight of 2.0
× 10²~ 1.0 x 10^FiveAre preferred.

(2) Examples of the alkali-soluble polymer compound having a sulfonamide group include, for example, a polymer having a compound having a sulfonamide group as a main monomer constituent unit, that is, a homopolymer or another monomer in the monomer constituent unit. Examples thereof include a copolymer obtained by copolymerizing a polymerizable monomer. Examples of the polymerizable monomer having a sulfonamide group include a sulfonamide group —SO ₂ —NH— having at least one hydrogen atom bonded to a nitrogen atom in one molecule,
Examples of the monomer include a low molecular weight compound having one or more polymerizable unsaturated bonds. Among them, a low molecular weight compound having an acryloyl group, an allyl group or a vinyloxy group and a substituted or mono-substituted aminosulfonyl group or a substituted sulfonylimino group is preferable. Examples of the low molecular weight compounds include compounds represented by the following general formulas (a) to (e), but the present invention is not limited thereto.

[0047]

In the formula, X ¹ and X ² each independently represent an oxygen atom or NR ⁷ . R ¹ and R ⁴ each independently represent a hydrogen atom or CH ₃ . R ² , R ⁵ , R ⁹ , R ¹² , and R ¹⁶ are
Each independently has 1 to 1 carbon atoms which may have a substituent.
2 represents an alkylene group, a cycloalkylene group, an arylene group or an aralkylene group. R ³ , R ⁷ , and R ¹³ each independently represent a hydrogen atom or a carbon atom which may have a substituent.
~ 12 represents an alkyl group, a cycloalkyl group, an aryl group or an aralkyl group. R ⁶ and R ¹⁷ each independently represent an alkyl group having 1 to 12 carbon atoms, which may have a substituent, a cycloalkyl group, an aryl group or an aralkyl group. R ⁸ , R ¹⁰ and R ¹⁴ each independently represent a hydrogen atom or CH ₃ . R ¹¹ and R ¹⁵ each independently represent a single bond or an alkylene group having 1 to 12 carbon atoms which may have a substituent, a cycloalkylene group, an arylene group or an aralkylene group. Y ¹ and Y ² each independently represent a single bond or CO.

Among them, m-aminosulfonylphenyl methacrylate, N- (p-aminosulfonylphenyl) methacrylamide, N- (p-aminosulfonylphenyl) acrylamide and the like can be preferably used.

As the alkali-soluble polymer compound having an active imide group (3), for example, a polymer having a compound having an active imide group as a main monomer constituent unit can be mentioned. As a polymer having a compound having an active imide group as a main monomer constitutional unit,
Obtained by homopolymerizing a monomer composed of a low molecular weight compound having an active imide group represented by the following formula and at least one polymerizable unsaturated bond, or by copolymerizing the monomer with another polymerizable monomer. A high molecular compound can be mentioned.

[0051]

Specific examples of such a compound include:
N- (p-toluenesulfonyl) methacrylamide, N
Preferable examples thereof include-(p-toluenesulfonyl) acrylamide. Further, in addition to the above, a polymer compound obtained by polymerizing any two or more of the above-mentioned polymerizable monomer having a phenol group, a polymerizable monomer having a sulfonamide group, and a polymerizable monomer having an active imide group, or Further, a polymer compound obtained by copolymerizing these two or more kinds of polymerizable monomers with another polymerizable monomer is also preferable.

Polymerizable monomer having a phenol group (M
1), a polymerizable monomer having a sulfonamide group (M
The compounding ratio (M1: M2 and / or M3; mass ratio) when 2) and / or the polymerizable monomer (M3) having an active imide group is copolymerized is 50:50 to 5:95.
Is preferred, and 40:60 to 10:90 is more preferred.

The alkali-soluble polymer compound is a copolymer composed of a monomer constitutional unit having any one of the acidic groups (1) to (3) and a constitutional unit of another polymerizable monomer. In this case, it is preferable that the copolymer contains 10 mol% or more of a monomer structural unit having any one of the acidic groups (1) to (3).
It is more preferable to contain 0 mol% or more. If the content of the monomer structural unit is less than 10 mol%, sufficient alkali solubility may not be obtained and the development latitude may be narrowed. As a method for synthesizing the copolymer, a conventionally known graft copolymerization method, block copolymerization method, random copolymerization method or the like can be used.

The monomer having any one of the acidic groups (1) to (3) is copolymerized with a polymerizable monomer having a constitutional unit. Examples of the other polymerizable monomer include the monomers listed in (a) to (1) below, but the present invention is not limited thereto.

(A) Acrylic acid esters and methacrylic acid esters having an aliphatic hydroxyl group such as 2-hydroxyethyl acrylate or 2-hydroxyethyl methacrylate. (B) Methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, amyl acrylate, hexyl acrylate, octyl acrylate, benzyl acrylate, 2-chloroethyl acrylate, glycidyl acrylate, N-dimethylaminoethyl Alkyl acrylate such as acrylate. (C) Methyl methacrylate, ethyl methacrylate, propyl methacrylate, butyl methacrylate, amyl methacrylate, hexyl methacrylate, cyclohexyl methacrylate, benzyl methacrylate, 2-chloroethyl methacrylate, glycidyl methacrylate, N-dimethylaminoethyl. Alkyl methacrylate such as methacrylate.

(D) Acrylamide, methacrylamide, N-methylolacrylamide, N-ethylacrylamide, N-hexylmethacrylamide, N-cyclohexylacrylamide, N-hydroxyethylacrylamide, N-phenylacrylamide, N-nitrophenylacrylamide , Acrylamide such as N-ethyl-N-phenylacrylamide, or methacrylamide. (E) Vinyl ethers such as ethyl vinyl ether, 2-chloroethyl vinyl ether, hydroxyethyl vinyl ether, propyl vinyl ether, butyl vinyl ether, octyl vinyl ether and phenyl vinyl ether. (F) Vinyl esters such as vinyl acetate, vinyl chloroacetate, vinyl butyrate and vinyl benzoate. (G) Styrene, α-methylstyrene, methylstyrene, chloromethylstyrene and the like and styrenes.

(H) Vinyl ketones such as methyl vinyl ketone, ethyl vinyl ketone, propyl vinyl ketone and phenyl vinyl ketone. (I) Olefins such as ethylene, propylene, isobutylene, butadiene and isoprene. (J) N-vinylpyrrolidone, N-vinylcarbazole, 4-vinylpyridine, acrylonitrile, methacrylonitrile and the like. (K) maleimide, N-acryloyl acrylamide,
Unsaturated imides such as N-acetylmethacrylamide, N-propionylmethacrylamide, and N- (p-chlorobenzoyl) methacrylamide. (L) Unsaturated carboxylic acids such as acrylic acid, methacrylic acid, maleic anhydride, and itaconic acid.

The alkali water-soluble polymer compound, regardless of homopolymer or copolymer, is
Weight average molecular weight of 2000 or more, number average molecular weight of 500
The above is preferable, and the weight average molecular weight is 5,000 to 3
00000, the number average molecular weight is 800 to 250,000, and the dispersity (weight average molecular weight / number average molecular weight) is 1.1 to
10 is more preferable. Further, the alkali-soluble polymer compound, phenol-formaldehyde resin,
In the case of a cresol-aldehyde resin or the like, those having a weight average molecular weight of 500 to 20,000 and a number average molecular weight of 200 to 10,000 are preferable.

The content of the alkaline water-soluble polymer compound is 30 to 30 with respect to the total solid content of the image forming layer.
99 mass% is preferable, 40-95 mass% is more preferable, 50-90 mass% is the most preferable. The content is
If it is less than 30% by mass, the durability of the image forming layer may decrease, and if it exceeds 99% by mass, the sensitivity and durability may decrease. Further, the polymer compound may be used alone or in combination of two or more kinds.

-(C) A compound which is compatible with the alkali-soluble polymer compound to reduce the solubility of the alkali-soluble polymer compound in an aqueous alkali solution, and which reduces the solubility-reducing action by heating- The component (C) has good compatibility with the above-mentioned (B) alkali-soluble polymer compound due to the function of the hydrogen-bonding functional group present in the molecule, and can form a uniform coating liquid for the image-forming layer. At the same time, it refers to a compound having a function of suppressing the alkali solubility of the alkali-soluble polymer compound by the interaction with the alkali-soluble polymer compound (solubility suppressing action).

Although the solubility-suppressing action on the alkali-soluble polymer compound disappears by heating, when the infrared absorbing agent itself is a compound which decomposes by heating, sufficient energy for decomposition is generated by laser output or laser output. If it is not given under various conditions such as irradiation time, the solubility-suppressing action of the alkali-soluble polymer compound cannot be sufficiently lowered, and the sensitivity may be lowered. For this reason,
The thermal decomposition temperature of the component (C) is preferably 150 ° C or higher.

As the component (C), in consideration of the interaction with the above-mentioned (B) alkali-soluble polymer compound, for example,
It can be appropriately selected from compounds capable of interacting with the alkali-soluble polymer compound, such as sulfone compounds, ammonium salts, phosphonium salts, and amide compounds.
In particular, for example, when a novolac resin is used alone as the component (B), the “(A + C) component” described below is used.
Is preferred, and the cyanine dye A exemplified below is more preferred. The component (A + C) will be described later. Generally, the compounding ratio (C / B) of the component (C) and the alkali-soluble polymer compound (B) is preferably 1/99 to 25/75. When the mixing ratio is less than 1/99, that is, when the amount of the component (C) is too small, the interaction with the alkali-soluble polymer compound becomes insufficient, the alkali solubility cannot be lowered, and good image formation is achieved. If it exceeds 25/75, that is, if the amount of component (C) is too large, the interaction may become excessive and the sensitivity may be significantly reduced.

-(A + C) component-In place of the (A) component and the (C) component, a compound having both properties ((A + C) component) can be used. The component (A + C) has a property of absorbing light to generate heat (that is, the property of the component (A)), and
It is a basic dye that has an absorption region in the wavelength region of 0 to 1200 nm and is also compatible with alkali-soluble polymer compounds. The component (A + C) has a group that interacts with the alkali-soluble polymer compound such as an ammonium group and an iminium group in its molecule (that is, the characteristic of the component (C)), and therefore it interacts with the polymer compound. , Its alkali solubility can be suppressed. Examples of the component (A + C) include compounds represented by the following general formula (Z).

[0065]

In the general formula (Z), R ^{21 to} R ²⁴ are each independently a hydrogen atom or an optionally substituted alkyl group having 1 to 12 carbon atoms, an alkenyl group, an alkoxy group, a cyclo group. It represents an alkyl group or an aryl group, and R ²¹ and R ²² , and R ²³ and R ²⁴ may be bonded to each other to form a ring structure. Examples of R ^{21 to} R ²⁴ include a hydrogen atom,
Examples thereof include a methyl group, an ethyl group, a phenyl group, a dodecyl group, a naphthyl group, a vinyl group, an allyl group and a cyclohexyl group, and these groups may further have a substituent. Here, as the substituent, for example, a halogen atom,
Carbonyl group, nitro group, nitrile group, sulfonyl group,
Examples thereof include a carboxyl group, a carboxylic acid ester, and a sulfonic acid ester.

In the formula, R ^{25 to} R ³⁰ each independently represent an alkyl group having 1 to 12 carbon atoms which may have a substituent, and examples of R ^{25 to} R ³⁰ include a methyl group, Examples thereof include an ethyl group, a phenyl group, a dodecyl group, a naphthyl group, a vinyl group, an allyl group, and a cyclohexyl group, and these groups may further have a substituent. Here, as the substituent, for example, a halogen atom, a carbonyl group,
Examples thereof include nitro group, nitrile group, sulfonyl group, carboxyl group, carboxylic acid ester and sulfonic acid ester.

In the formula, R ^{31 to} R ³³ each independently represent a hydrogen atom, a halogen atom, or an alkyl group having 1 to 8 carbon atoms which may have a substituent, and R ³² represents R ³¹ described above. Alternatively, it may combine with R ³³ to form a ring structure, and when m> 2, a plurality of R ^{32 s} may combine with each other to form a ring structure. Examples of R ^{31 to} R ³³ include a chlorine atom, a cyclohexyl group, a cyclopentyl ring formed by combining R ^32's , a cyclohexyl ring, and the like, and these groups may further have a substituent. .. Here, as the substituent, for example, a halogen atom, a carbonyl group, a nitro group, a nitrile group, a sulfonyl group, a carboxyl group,
Examples thereof include carboxylic acid ester and sulfonic acid ester. Moreover, m represents the integer of 1-8, and 1-3 are preferable especially.

In the formula, R ^{34 to} R ³⁵ each independently represents a hydrogen atom, a halogen atom, or an alkyl group having 1 to 8 carbon atoms which may have a substituent, and R ³⁴ is the same as R ³⁵ . They may be bonded to each other to form a ring structure, and when m> 2, a plurality of R ³⁴ 's may be bonded to each other to form a ring structure. Examples of R ^{34 to} R ³⁵ include a chlorine atom, a cyclohexyl group, a cyclopentyl ring formed by combining R ^34's , a cyclohexyl ring, and the like, and these groups may further have a substituent. .. Here, examples of the substituent include a halogen atom, a carbonyl group, a nitro group, a nitrile group, a sulfonyl group, a carboxyl group, a carboxylic acid ester, a sulfonic acid ester, and the like. Also, m
Represents an integer of 1 to 8, and among them, 1 to 3 are preferable.

In the formula, X ⁻ represents an anion, for example,
Perchloric acid, tetrafluoroboric acid, hexafluorophosphoric acid, triisopropylnaphthalenesulfonic acid, 5-nitro-O-toluenesulfonic acid, 5-sulfosalicylic acid, 2,5-dimethylbenzenesulfonic acid, 2,4. 6-trimethylbenzenesulfonic acid, 2-nitrobenzenesulfonic acid, 3-
Chlorobenzenesulfonic acid, 3-bromobenzenesulfonic acid, 2-fluorocaprylnaphthalenesulfonic acid, dodecylbenzenesulfonic acid, 1-naphthol-5-sulfonic acid, 2-methoxy-4-hydroxy-5-benzoyl-benzenesulfonic acid and para. Examples include toluene sulfonic acid. Of these, alkylaromatic sulfonic acids such as hexafluorophosphoric acid, triisopropylnaphthalenesulfonic acid, and 2,5-dimethylbenzenesulfonic acid are preferable.

The compound represented by the general formula (Z) is a compound generally called a cyanine dye. Specifically, the following compounds are preferably used, but in the present invention, the compounds are not limited thereto. Not a thing.

When the component (A + C) having both characteristics is used in place of the component (A) and the component (C), the ratio of the amount of the component (A + C) and the component (B) used []. As (A + C) / (B)], 1/99 to 30
/ 70 is preferable, and 1/99 to 25/75 is more preferable.

-(D) Cyclic acid anhydride-A cyclic acid anhydride may be further used in the lithographic printing plate precursor. The cyclic acid anhydride has a bond conjugated to the carbonyl group of the carboxylic acid anhydride in its structure, the decomposition rate is controlled by increasing the stability of the carbonyl group, and the cyclic acid anhydride decomposes at an appropriate rate during storage. And generate acid. Therefore, it is possible to suppress the deterioration of the developability over time and to maintain the developability stably for a long period of time. Examples of the cyclic acid anhydride include compounds represented by the following general formula (I) or (II).

[0074]

In the general formula (I), R ⁴¹ and R ⁴² are each independently a hydrogen atom, or an optionally substituted alkyl group having 1 to 12 carbon atoms, an alkenyl group, an alkoxy group or a cycloalkyl group. Represents a group, an aryl group, a carbonyl group, a carboxy group or a carboxylic acid ester. In addition,
R ⁴¹ and R ⁴² may combine with each other to form a ring structure.
Preferable examples of R ⁴¹ and R ⁴² include a hydrogen atom, or an unsubstituted alkyl group having 1 to 12 carbon atoms, an aryl group, an alkenyl group, a cycloalkyl group, and the like. Methyl group, ethyl group, phenyl group,
Examples thereof include a dodecyl group, a naphthyl group, a vinyl group, an allyl group, a cyclohexyl group, and these groups may further have a substituent. When R ⁴¹ and R ⁴² are linked to each other to form a ring structure, examples of the cyclic group include a phenylene group, a naphthylene group, a cyclohexene group and a cyclopentene group. Examples of the substituent include a halogen atom, a hydroxy group, a carbonyl group, a sulfonic acid ester, a nitro group and a nitrile group.

In the general formula (II), R ⁴³ , R ⁴⁴ , R ⁴⁵ and R ⁴⁶
Are each independently a hydrogen atom, a hydroxyl group, a halogen atom such as chlorine, a nitro group, a nitrile group, or an optionally substituted alkyl group having 1 to 12 carbon atoms, an alkenyl group, an alkoxy group, a cyclo group. It represents an alkyl group, an aryl group, a carbonyl group, a carboxy group, a carboxylic acid ester group, or the like. Examples of R ⁴³ , R ⁴⁴ , R ⁴⁵ and R ⁴⁶ include a hydrogen atom, a halogen atom and a carbon atom of 1
Preferable examples thereof include an unsubstituted alkyl group having ˜12, an alkenyl group and an aryl group having 6 to 12 carbon atoms, and specific examples thereof include a methyl group, a vinyl group, a phenyl group and an allyl group. These groups may further have a substituent. Examples of the substituent include a halogen atom, a hydroxy group, a carbonyl group, a sulfonic acid ester, a nitro group, a nitrile group and a carboxy group.

As the cyclic acid anhydride, for example, phthalic anhydride, 3,4,5,6-tetrahydrophthalic anhydride, tetrachlorophthalic anhydride, 3-hydroxyphthalic anhydride,
3-methylphthalic anhydride, 3-phenylphthalic anhydride,
Preferable examples include trimellitic anhydride, pyromellitic anhydride, maleic anhydride, phenylmaleic anhydride, dimethylmaleic anhydride, dichloromaleic anhydride and chloromaleic anhydride. The content of the cyclic acid anhydride is preferably 0.5 to 20% by mass, more preferably 1 to 15% by mass, and 1 to 1 with respect to the total solid content of the image forming layer.
Most preferred is 0% by weight. When the content is less than 0.5% by mass, the effect of maintaining developability may be insufficient,
If it exceeds 20% by mass, an image may not be formed.

The following are components constituting the recording layer of the negative type lithographic printing plate. — (E) Compound that Generates Acid by Heat— When the image forming material is a negative type, a compound that generates an acid when heated (hereinafter, referred to as “acid generator”) is used in combination. This acid generator decomposes when heated to 100 ° C. or higher to increase the compound that generates an acid. As the acid generated,
A strong acid having a pKa of 2 or less, such as sulfonic acid or hydrochloric acid, is preferable. The acid generator, iodonium salt,
Preferable examples are onium salts such as sulfonium salts, phosphonium salts and diazonium salts. In particular,
U.S. Pat. No. 4,708,925 and JP-A-7-20629
The compounds described in JP-A No. 2004-242242 can be mentioned, and among them, iodonium salts, sulfonium salts, and diazonium salts having a sulfonate ion as a counter ion are preferable.

Examples of the diazonium salt include diazonium salt compounds described in US Pat. No. 3,867,147,
Diazonium compounds described in U.S. Pat. No. 2,632,703, JP-A-1-102456 and JP-A-1-
The diazo resin described in each publication of 102457 can also be mentioned suitably. Also, US Pat. No. 5,135,83
No. 8, benzyl sulfonates described in US Pat. No. 5,200,544, active sulfonic acid esters and disulfonyls described in JP-A Nos. 2-100054, 2-100055, and 8-9444. Compounds are also preferred. In addition, haloalkyl-substituted S-triazines described in JP-A-7-271029 are also preferable. The amount of the acid generator added is preferably 0.01 to 50% by mass, and 0.1 to 40% by mass based on the total solid content of the image forming layer.
Is more preferable, and 0.5 to 30 mass% is the most preferable.

-(F) Acid-crosslinking agent-When the lithographic printing plate precursor is a negative type, an acid-crosslinking agent (hereinafter sometimes simply referred to as "crosslinking agent") is used in combination. The following can be mentioned as said crosslinking agent. (I) Aromatic compound substituted with alkoxymethyl group or hydroxymethyl group (ii) Compound having N-hydroxymethyl group, N-alkoxymethyl group or N-acyloxymethyl group (iii) Epoxy compound Examples thereof include those described in JP-A-254850 and phenol derivatives.

The amount of the cross-linking agent added is preferably 5 to 80% by mass, based on the total mass of the solid content of the image forming layer.
-75 mass% is more preferable, and 20-70 mass% is the most preferable. When the phenol derivative is used as a crosslinking agent, the amount of the phenol derivative added is preferably 5 to 70% by mass, and more preferably 10 to 50% by mass, based on the total solid mass of the image forming material. Details of the above various compounds are described in JP-A-2000-267265.

-Other Components-Various additives may be further added to the image forming layer of the lithographic printing plate precursor, if necessary. For example, known additives such as phenols, organic acids and sulfonyl compounds can be used in combination for the purpose of improving sensitivity. Examples of phenols include bisphenol A, p-nitrophenol, p-ethoxyphenol, 2,4.
4'-trihydroxybenzophenone, 2,3,4-trihydroxybenzophenone, 4-hydroxybenzophenone, 4,4 ', 4 "-trihydroxytriphenylmethane, 4,4', 3", 4 "-tetrahydroxy-
3,5,3 ', 5'-tetramethyltriphenylmethane and the like can be mentioned.

Examples of the organic acids include those disclosed in JP-A-60-8.
There are sulfonic acids, sulfinic acids, alkylsulfuric acids, phosphonic acids, phosphoric acid esters, carboxylic acids and the like described in Japanese Patent Publication No. 8942, Japanese Patent Application Laid-Open No. 2-96755 and the like, and specifically, p-toluene. Sulfonic acid, dodecylbenzenesulfonic acid, p-toluenesulfinic acid, ethylsulfate, phenylphosphonic acid, phenylphosphinic acid, phenyl phosphate, diphenyl phosphate, benzoic acid, isophthalic acid, adipic acid, p-toluic acid,
Examples thereof include 3,4-dimethoxybenzoic acid, phthalic acid, terephthalic acid, 4-cyclohexene-2,2-dicarboxylic acid, erucic acid, lauric acid, n-undecanoic acid, and ascorbic acid. Examples of the sulfonyl compounds include bishydroxyphenyl sulfone, methylphenyl sulfone, diphenyldisulfone and the like. The addition amount of the other cyclic acid anhydride, phenols, organic acids or sulfonyl compounds is preferably 0.05 to 20 mass% with respect to the total solid mass of the image forming layer, and 0.1 to 1
5 mass% is more preferable, and 0.1-10 mass% is the most preferable.

Further, for the purpose of expanding the stability of processability under developing conditions, a siloxane compound as described in EP 950517, JP-A-11-28809.
Fluorine-containing monomer copolymers such as those described in JP-A-3 can be added. As the siloxane-based compound, a block copolymer of dimethylsiloxane and polyalkylene oxide is preferable.
Made by Chisso Corporation, DBE-224, DBE-621, DBE
-712, DBP-732, DBP-534, German Teg
Polyalkylene oxide-modified silicone such as Tego Glide 100 manufactured by O Co. may be mentioned. The amount of the surfactant used, based on the total solid content of the image forming layer, 0.
05 to 15 mass% is preferable, and 0.1 to 5 mass% is more preferable.

After the image forming layer is heated by exposure,
A printout agent for obtaining a visible image or a dye or pigment as an image colorant can be added immediately. Examples of the printing-out agent include a combination of a compound that generates an acid when heated by exposure to light and an organic dye that can form a salt. Specifically, combinations of o-naphthoquinonediazide-4-sulfonic acid halogenide and a salt-forming organic dye described in JP-A-50-36209 and JP-A-53-8128, and JP-A- 53-36223, JP-A-54
-74728, JP-A-60-3626, JP-A-61
The combination of a trihalomethyl compound and a salt-forming organic dye described in JP-A-143748, JP-A-61-151644 and JP-A-63-58440. As the trihalomethyl compound, there are an oxazole compound and a triazine compound, both of which have excellent stability over time and give a clear printout image. As the image colorant, for example, other dyes can be used in addition to the salt-forming organic dye, and for example, oil-soluble dyes and basic dyes are suitable.

Specifically, Oil Yellow # 101, Oil Yellow # 103, Oil Pink # 312, Oil Green BG, Oil Blue BOS, Oil Blue # 6.
03, oil black BY, oil black BS, oil black T-505 (above, manufactured by Orient Chemical Industry Co., Ltd.), Victoria Pure Blue, crystal violet (CI. 42555), methyl violet (CI. 42535). , Ethyl violet, rhodamine B (CI. 145170B), malachite green (CI. 42000), methylene blue (CI.
52015) and the like. In addition, JP-A-6
The dyes described in JP-A-2-293247 are particularly preferable. The amount of the various dyes added is preferably 0.01 to 10% by mass, based on the total mass of the solid content of the image forming layer.
-3 mass% is more preferable.

If desired, a plasticizer may be added for the purpose of imparting flexibility to the coating film. Examples of the plasticizer include butylphthalyl, polyethylene glycol, tributyl citrate, diethyl phthalate, dibutyl phthalate, dihexyl phthalate, dioctyl phthalate, tricresyl phosphate, tributyl phosphate, trioctyl phosphate, tetrahydrofurfuryl oleate, and acrylic. Examples thereof include oligomers and polymers of acid or methacrylic acid.

If necessary, the following various additives can be added. For example, onium salts, o-quinonediazide compounds, aromatic sulfone compounds, aromatic sulfonic acid ester compounds, and other compounds that are thermally decomposable and substantially reduce the solubility of the alkaline water-soluble polymer compound in the undecomposed state can be used. Can be used together. Addition of the compound is preferable from the viewpoint of improving the dissolution inhibiting ability of the image area in the developing solution. Examples of the onium salts include diazonium salts, ammonium salts, phosphonium salts, iodonium salts, sulfonium salts, selenonium salts, arsonium salts and the like. Among them, for example SI Schlesinger,
Photogr. Sci. Eng., 18, 387 (1974), TSBal et al,
Polymer, 21, 423 (1980), the diazonium salt described in JP-A-5-158230, U.S. Pat. No. 4,069,
055, 4,069,056, and JP-A-3-140.
Ammonium salt described in No. 140, DC Necker et a
l, Macromolecules, 17, 2468 (1984), CS Wen et a
l, The Proc. Conf. Rad. Curing ASIA, p478 Tokyo, O
ct (1988), US Pat. Nos. 4,069,055 and 4,
069,056 phosphonium salt, JV Criv
elloet et al. Macromolecules, 10 (6), 1307 (1977),
Chem. & Eng. News, Nov. 28, p. 31 (1988), European Patent 104,143, US Patents 339,049, 410,201, JP-A-2-150848, JP-A-2-150848. 2-296514, iodonium salts,

JV Crivello et al, Polymer J. 17, 7
3 (1985), JV Crivello et al, J.Org. Chem., 43,
3055 (1978), W. R, Watt et al, J. Polymer Sci., Po
lymerChem. Ed., 22, 1789 (1984), JV Crivello et
al, Polymer bull., 14, 279 (1985), JV Crivello
et al, Macromolecules, 14 (5), 1141 (1981), JVCr
ivello et al, J. Polymer Sci., Polymer Chem. Ed.,
17. 2877 (1979), European Patent Nos. 370,693 and 2
33,567, 297,443, 297,44
No. 2, US Pat. Nos. 4,933,377 and 3,90.
2,114, 410,201, 399,049
No. 4, ibid. 4,760,013, ibid. 4,734,444
No. 2,833,827, German Patent No. 2,904,
No. 626, No. 3,604,580, No. 3,604,5
No. 81, a sulfonium salt,

JV Crivello et al, Macromolecules,
10 (6), 1307 (1977), JV Crivelloet al, J. Polymer
Sci., Polymer Chem. Ed., 17, 1047 (1979), selenonium salt, CS Wen et al, The Proc. Conf. R
Examples include arsonium salts described in ad. Curing ASIA, p.478, Tokyo, Oct (1988). Of the above, diazonium salts are preferable, and among them, JP-A-5-158230.
The one described in the publication is more preferable.

As the counter ion of the onium salt, tetrafluoroboric acid, hexafluorophosphoric acid, triisopropylnaphthalenesulfonic acid, 5-nitro-o-toluenesulfonic acid, 5
-Sulfosalicylic acid, 2,5-dimethylbenzenesulfonic acid, 2,4,6-trimethylbenzenesulfonic acid, 2
-Nitrobenzenesulfonic acid, 3-chlorobenzenesulfonic acid, 3-bromobenzenesulfonic acid, 2-fluorocaprylnaphthalenesulfonic acid, dodecylbenzenesulfonic acid, 1-naphthol-5-sulfonic acid, 2-methoxy-4-hydroxy-5- Examples thereof include benzoyl-benzenesulfonic acid and paratoluenesulfonic acid. Of these, alkylaromatic sulfonic acids such as hexafluorophosphoric acid, triisopropylnaphthalenesulfonic acid, and 2,5-dimethylbenzenesulfonic acid are preferable.

Examples of the o-quinonediazide compound include
Compounds having at least one o-quinonediazide group, which increase alkali solubility by thermal decomposition, can be mentioned, and compounds having various structures can be used. Said o
-Quinonediazide helps the solubility of the lithographic printing plate precursor by both effects of losing the ability to inhibit the dissolution of the binder by thermal decomposition and changing the o-quinonediazide itself into an alkali-soluble substance.

Examples of the o-quinonediazide compound as described above include those described in J. 33, "Light-Sensitive Systems" by John Coley, John Wiley & Sons. Inc.
Although the compounds described on pages 9 to 352 can be used, sulfonic acid esters or sulfonic acid amides of o-quinonediazide reacted with various aromatic polyhydroxy compounds or aromatic amino compounds are preferable. Further, benzoquinone (1,2) -diazide sulfonic acid chloride described in JP-A-43-28403 or US Pat. Nos. 3,046,120 and 3,188,210.
Also preferred are the esters of benzoquinone- (1,2) -diazide sulfonic acid chloride or naphthoquinone- (1,2) -diazide-5-sulfonic acid chloride described in US Pat.

Furthermore, an ester of naphthoquinone- (1,2) -diazide-4-sulfonic acid chloride and a phenol formaldehyde resin or a cresol-formaldehyde resin, naphthoquinone- (1,2) -diazide-4-sulfonic acid chloride and pyrogallol. Esters with acetone resins are also preferred. Others, for example, JP-A-4
7-5303, JP-A-48-63802, JP-A-4.
8-63803, JP-A-48-96575, JP-A-49-38701, JP-A-48-13354, JP-B-41-11222, JP-B-45-9610, JP-B-49-17481, US Pat. No. 2,797,213
No. 3, No. 3,454, 400, No. 3, 544, 32
No. 3, No. 3,573,917, No. 3,674,4
95, 3,785,825, British Patents 1,2
No. 27,602, No. 1,251,345, No. 1,
Those described in 267,005, 1,329,888, 1,330,932, German Patent 854,890 and the like are also useful. These compounds may be used alone or in combination of several kinds. The addition amount of the onium salt, o-quinonediazide compound, aromatic sulfonic acid ester or the like is preferably 0.1 to 50% by mass with respect to the total solid mass of the image forming layer,
0.5-30 mass% is more preferable, and 0.5-20 mass% is the most preferable.

In addition, for the purpose of enhancing image discrimination and resistance to surface scratches, a polymer having 3 to 20 carbon atoms in a molecule as described in JP-A-2000-187318 is used. It is preferable to use a polymer having a (meth) acrylate monomer having 2 or 3 fluoroalkyl groups as a polymerization component. The addition amount is preferably 0.1 to 10% by mass, and more preferably 0.5 to 5% by mass, based on the total mass of the solid content of the image forming layer. Further, for the purpose of imparting resistance to scratches, a compound that lowers the coefficient of static friction of the surface can be added. Specific examples thereof include esters of long-chain alkylcarboxylic acids as disclosed in US Pat. No. 6,117,913. The addition amount thereof is preferably 0.1 to 10% by mass, and more preferably 0.5 to 5% by mass, based on the total mass of the solid content of the image forming layer. Further, various dissolution inhibitors may be included for the purpose of adjusting the solubility of the image forming layer. As a dissolution inhibitor, JP-A-11
A disulfone compound or a sulfone compound described in JP-A-119418 is preferably used, and 4,4′-bishydroxyphenylsulfone is preferably used as a specific example. The addition amount thereof is preferably 0.05 to 20% by mass, more preferably 0.5 to 10% by mass, based on the total solid content of the image forming layer.

As a specific example of a photosensitive lithographic printing plate to which the plate-making method of the present invention can be applied, a lithographic printing method in which an image forming layer as disclosed in Japanese Patent Application No. 2000-378507 is used as a positive heat-sensitive layer having a two-layer structure. The original edition is also included. That is, this positive-type heat-sensitive layer has a laminated structure and comprises a heat-sensitive layer provided at a position close to the surface (exposed surface) and a lower layer containing an alkali-soluble polymer compound provided on the side closer to the support. It is characterized by having. The above-mentioned (A) infrared absorbing dye, (B) alkali-soluble polymer compound, (C) alkali-soluble polymer compound which is compatible with the above-mentioned (A) infrared-absorbing dye, in one or both of the heat-sensitive layer and the lower layer. It is possible to include a compound, which reduces the solubility of the compound in an alkaline aqueous solution and reduces the solubility-decreasing action by heating, and other components. As the alkali-soluble polymer compound used in the lower layer, an acrylic resin can maintain good solubility of the lower layer in an alkali developing solution containing a buffering organic compound and a base as main components, and therefore, during development. Is preferable from the viewpoint of image formation. Further, the acrylic resin having a sulfamide group is particularly preferable. Further, as the alkali-soluble polymer compound used in the heat-sensitive layer, a strong hydrogen bonding property is generated in the unexposed area,
In the exposed area, a resin having a phenolic hydroxyl group is desirable because some hydrogen bonds are easily released. More preferably, it is a novolac resin. The infrared absorbing dye can be added not only to the heat-sensitive layer but also to the lower layer. The lower layer can also function as a heat-sensitive layer by adding an infrared absorbing dye to the lower layer. When the infrared absorbing dye is added to the lower layer, the same materials as those in the upper heat-sensitive layer may be used, or different materials may be used. Other additives may be contained only in the lower layer,
It may be contained only in the heat sensitive layer, or may be contained in both layers.

The image forming layer (including the above-mentioned two-layer structure) of the lithographic printing plate precursor can be coated on a suitable support by dissolving each of the above components in a solvent. Examples of the solvent include ethylene dichloride, cyclohexanone, methyl ethyl ketone, methanol, ethanol, propanol, ethylene glycol monomethyl ether, 1-methoxy-2.
-Propanol, 2-methoxyethyl acetate, 1-
Methoxy-2-propylacetate, dimethoxyethane, methyl lactate, ethyl lactate, N, N-dimethylacetamide, N, N-dimethylformamide, tetramethylurea, N-methylpyrrolidone, dimethyl sulfoxide, sulfolane, α-butyrolactone, toluene, etc. However, the present invention is not limited to these. The above solvents may be used alone or in combination of two or more.

When the image-forming layer has a two-layer structure, it is preferable to select those having different solubilities with respect to the alkali-soluble polymer compound used for the heat-sensitive layer and the alkali-soluble polymer compound used for the lower layer. That is, after applying the lower layer, when applying a heat-sensitive layer that is the upper layer adjacent to it, if a solvent capable of dissolving the alkali-soluble polymer compound of the lower layer is used as the coating solvent for the uppermost layer, the mixing at the layer interface will occur. It cannot be ignored, and in extreme cases, it may become a uniform single layer instead of multiple layers. Therefore, the solvent used for coating the upper heat-sensitive layer is preferably a poor solvent for the alkali-soluble polymer compound contained in the lower layer.

When the image forming layer is applied, the total solid concentration of the above components in the solvent is generally preferably 1 to 10% by mass. The dry coating amount (solid content) of the image forming layer formed by coating and drying the support is generally 0.5.
It is preferably up to 5.0 g / m ² . When using a two-layer structure,
The heat sensitive layer is 0.05 to 1.0 g / m ² , and the lower layer is 0.
It is preferably ³ to 3.0 g / m ² . As the coating amount decreases, the apparent sensitivity increases, but the film characteristics of the image forming layer deteriorate. The method for coating on the support can be appropriately selected from various known methods,
Examples thereof include bar coater coating, spin coating, spray coating, curtain coating, dip coating, air knife coating, grade coating and roll coating. A surfactant such as the fluorine-based surfactant described in JP-A-62-170950 may be added to the coating liquid for the image forming layer for the purpose of improving the coatability. The amount added is 0.0 with respect to the total solid content of the image forming layer.
1-1 mass% is preferable, and 0.05-0.5 mass% is more preferable.

—Support— Examples of the support for the lithographic printing plate precursor include a pure aluminum plate, an aluminum alloy plate, and a plastic film on which aluminum is laminated or vapor deposited. The surface of the aluminum plate is preferably subjected to surface treatment such as graining treatment, permeation treatment with an aqueous solution of sodium silicate, potassium fluorozirconate, phosphate or the like, or anodization treatment. In addition, after graining the aluminum plate described in US Pat. No. 2,714,066 and then dipping it in an aqueous solution of sodium silicate, the aluminum plate described in Japanese Patent Publication No. 47-5125 is anodized. An aluminum plate that has been immersed in an aqueous solution of an alkali metal silicate is also preferable.

As the anodizing treatment, for example, sulfuric acid,
Anodize an aluminum plate in an electrolytic solution of inorganic acid such as phosphoric acid, chromic acid, nitric acid, boric acid, etc., or organic acid such as oxalic acid, sulfamic acid, etc. Is applied by flowing an electrode. Also, US Pat. No. 3,65
The silicate electrodeposition described in the specification of No. 8,662 is also effective.

US Pat. No. 4,087,341, JP-B-46-27481, and JP-A-52-3.
It is also useful that the support described in Japanese Patent No. 0503, which has been subjected to electrolytic graining, is subjected to the anodizing treatment. Aluminum sheets which have been grained, chemically etched and further anodized as described in US Pat. No. 3,834,998 are also useful. These treatments are performed for the purpose of making the surface of the support hydrophilic, for the purpose of preventing harmful reaction with the image forming layer provided on the support, and for improving the adhesion to the image-formed image. It is given for various purposes such as.

The lithographic printing plate precursor is one in which at least an image forming layer is laminated on a support, but an undercoat layer may be provided on the support if necessary. Examples of components used in the undercoat layer include various organic compounds,
For example, phosphonic acids having an amino group such as carboxymethyl cellulose, dextrin, gum arabic, and 2-aminoethylphosphonic acid; phenylphosphonic acid which may have a substituent, naphthylphosphonic acid, alkylphosphonic acid, glycerophosphonic acid, methylene Organic phosphonic acids such as diphosphonic acid and ethylenediphosphonic acid; phenylphosphoric acid which may have a substituent, naphthylphosphoric acid,
Organic phosphoric acid such as alkyl phosphoric acid and glycerophosphoric acid;
Organic phosphinic acids such as phenylphosphinic acid which may have a substituent, naphthylphosphinic acid, alkylphosphinic acid and glycerophosphinic acid; glycine and β-
Amino acids such as alanine; and hydrochlorides of amines having a hydroxyl group such as triethanolamine hydrochloride. The organic compounds may be used alone or in combination of two or more. It is also a preferable embodiment to undercoat the above-mentioned diazonium salt.

As the undercoat layer, the following general formula (II
An organic undercoat layer containing at least one organic polymer compound having a structural unit represented by I) is also preferable.

[0105]

In the formula, R⁵¹Is a hydrogen atom, a halogen atom or
Represents an alkyl group, R⁵²And R⁵³Each independently water
Elemental atom, hydroxyl group, halogen atom, alkyl group, substituted alkyl
Kill group, aryl group, substituted aryl group, -OR⁵⁴, -C
OOR⁵⁵, -CONHR⁵⁶, -COR⁵⁷Or-show CN
And the R⁵²And R⁵³Combine with each other to form a ring structure
May be. Where R⁵⁴~ R⁵⁷Each independently
Represents an aryl group or an aryl group. X is a hydrogen atom, a metal atom,
-NR⁵⁸R⁵⁹R⁶⁰R⁶¹Represents Where R⁵⁸~ R ⁶¹Is it
Each independently a hydrogen atom, an alkyl group, a substituted alkyl group,
Represents a reel group or a substituted aryl group, R⁵⁸And R⁵⁹Are mutual
They may be bonded to each other to form a ring structure. m is 1 to 3
Represents a number. The dry coating amount of the undercoat layer is 2 to 200 m
g / m²Is preferred, 5-100 mg / m²Is more preferred
Yes. This dry coating amount is 2 mg / m²Is less than enough
The film property may not be obtained. Meanwhile, 200 mg / m²To
Even if you apply more than that, you cannot get any further effect.
Yes.

The undercoat layer can be provided by the following method. That is, water or methanol, ethanol, an organic solvent such as an organic solvent such as methyl ethyl ketone or a mixed solvent thereof, a solution for the undercoat layer is applied on a support such as an aluminum plate, and a method for providing it by drying,
Water or an organic solvent such as methanol, ethanol, methyl ethyl ketone, or a mixed solvent thereof in a solution for the undercoat layer, a support such as an aluminum plate is immersed to adsorb the organic compound, and then water, etc. It is a method of washing and drying with.

In the former method, 0.000 of the organic compound is used.
It is preferable to use an undercoat layer solution having a concentration of 5 to 10% by mass. On the other hand, in the latter method, the concentration of the organic compound in the undercoat layer solution is suitably 0.01 to 20% by mass, preferably 0.05 to 10% by mass, and more preferably 0.1 to 10% by mass. Is about 5% by mass. The immersion temperature is preferably 20 to 90 ° C, more preferably 25 to 50 ° C. The immersion time is preferably 0.1 second to 20 minutes, and 2
Seconds to 1 minute are more preferable. For the undercoat layer solution, use a basic substance such as ammonia, triethylamine and potassium hydroxide or an acidic substance such as hydrochloric acid and phosphoric acid to adjust the pH to 1 to 12.
It can also be adjusted within the range. Further, a yellow dye may be added for the purpose of improving tone reproducibility.

The infrared-sensitive lithographic printing plate can be recorded by an infrared laser, recording by an ultraviolet lamp or thermal recording by a thermal head or the like. As the infrared laser, a laser emitting infrared rays having a wavelength of 700 to 1200 nm is preferable, and a solid laser or a semiconductor laser emitting infrared rays in the same wavelength range is more preferable.

[0110]

EFFECTS OF THE INVENTION According to the present invention, while maintaining the liquid condition of the alkaline developing solution, the generation of insoluble matter due to the binder resin, the infrared absorber, etc. and the adhesion to the plate surface are suppressed,
Provided is an alkaline developing treatment solution for a lithographic printing plate, which enables stable development for a long period of time, and a method for making a lithographic printing plate.

[0111]

The present invention will be described in detail below with reference to examples, but the present invention is not limited thereto. In addition,
All "%" in the examples represent "mass%".

[Preparation of alkaline developing solution containing SiO ₂ ] Mixing ratio of silicon oxide SiO ₂ and potassium oxide K ₂ O SiO ₂ / K ₂
Water-soluble soybean polysaccharide A or B shown below was added to 1 liter of a 4.0% potassium silicate aqueous solution having O of 1.1 at the concentration (g / liter) shown in Table 1 to carry out the alkali development of the present invention. Treatment liquids (1) to (10) were prepared. For comparison, a developer having the above composition and containing no water-soluble soybean polysaccharide was used as a developing solution (21).

[0112]

[Preparation of Non-Reducing Sugar-Containing Alkali Development Processing Solution] 1 liter of a 5.0% aqueous solution of a potassium salt of D-sorbit / potassium oxide K ₂ O in which a non-reducing sugar and a base were combined was added to the following water-soluble soybeans. Saccharides A or B concentrations listed in Table 1
(g / liter) to prepare alkali developing treatment solutions (11) to (20) of the present invention. For comparison, a developing solution (22) having the above composition and containing no such compound was used.

Water-soluble soybean polysaccharide A: trade name Soyafive-S-DN (manufactured by Fuji Oil Co., Ltd.) (Analysis value: galactose 4
6.1%, arabinose 22.6%, galacturonic acid 1
8.2%, crude protein 9.2%) Water-soluble soybean polysaccharide B: trade name Soyafive-S-LN
(Fuji Oil Co., Ltd.) (Analytical value: 43.6% galactose, 22.5% arabinose, 2.2% galacturonic acid, 10.4% crude protein)

[0114]

[Table 1]

[0115]

Examples 1 to 20 and Comparative Examples 1 and 2 Examples 1 to 20
The infrared-sensitive lithographic printing plate used in Comparative Examples 1 and 2 was prepared as follows. Each of Examples 1 to 10 was treated with an alkali developing treatment solution (1) to (10), and each of Examples 11 to 2 was treated.
No. 0 was treated with the alkali developing treatment solutions (11) to (20), and Comparative Examples 1 and 2 were treated with the alkali developing treatment solutions (2) to (2).
Processed in 1) and (22).

<Preparation of lithographic printing plate precursor 1> 0.3 mm thickness
Aluminum plate (material 1050) of trichlorethylene
After cleaning and degreasing with a nylon brush and 400 mesh
Using a Pumis-water suspension of
Washed well with water. After cleaning, this aluminum plate is 45
Immerse in 25% sodium hydroxide aqueous solution at ℃ for 9 seconds
Etching and washing with water, then 20% nitric acid solution
It was immersed in the solution for 20 seconds and washed again with water. Graining at this time
Surface etching rate is about 3g / m ²Met.

Next, this aluminum plate was charged with 7% sulfuric acid.
Current density of 15 A / dm ²DC current of 3g
/ M²After providing the anodic oxide coating of No. 1, washed with water and dried. This
This is treated with a 2.5% aqueous solution of sodium silicate at 30 ° C for 10 seconds.
After processing, apply the following undercoat layer coating solution and apply at 80 ° C for 1
After drying for 5 seconds, a support was obtained. Drying the undercoat layer after drying
The coating amount is 15 mg / m²Met.

<Undercoat Layer Coating Liquid> The following copolymer P (molecular weight 28,000) 0.3 g 100 g of methanol 1 g water

[0119]

<Synthesis of Specific Copolymer> Synthesis Example (Specific Copolymer 1) 31.0 g (0.36 mol) of methacrylic acid was added to a 500 ml three-necked flask equipped with a stirrer, a condenser and a dropping funnel.
39.1 g (0.36 mol) of ethyl chloroformate and 200 ml of acetonitrile were added, and the mixture was stirred while cooling with an ice water bath. Triethylamine 36.4 was added to this mixture.
g (0.36 mol) was added dropwise by a dropping funnel over about 1 hour. After completion of the dropping, remove the ice-water bath and let it stand at room temperature for 3
The mixture was stirred for 0 minutes. To this reaction mixture, 51.7 g (0.30 mol) of p-aminobenzenesulfonamide was added, and the mixture was stirred for 1 hour while warming to 70 ° C in an oil bath. After completion of the reaction, this mixture was put into 1 liter of water while stirring the water, and the resulting mixture was stirred for 30 minutes. The mixture is filtered to remove the precipitate, which is slurried with 500 ml of water and then the slurry is filtered,
The obtained solid was dried to obtain a white solid of N- (p-aminosulfonylphenyl) methacrylamide (yield 46.9 g).

Next, in a 20 ml three-necked flask equipped with a stirrer, a condenser and a dropping funnel, 4.61 g of N- (p-aminosulfonylphenyl) methacrylamide, (0.0192 mol) and 2.94 g of ethyl methacrylate ( 0.0258 mol), acrylonitrile 0.80 g (0.015 mol)
And 20 g of N, N-dimethylacetamide were added, and the mixture was stirred while heating at 65 ° C. in a hot water bath. To this mixture was added 0.15 g of "V-65" (manufactured by Wako Pure Chemical Industries, Ltd.), and the mixture was stirred under a nitrogen stream for 2 hours while maintaining the temperature at 65 ° C. The reaction mixture was further added with N- (p-aminosulfonylphenyl) methacrylamide 4.61 g, ethyl methacrylate 2.94 g, acrylonitrile 0.80 g, N, N-
A mixture of dimethylacetamide and 0.15 g of "V-65" was added dropwise by a dropping funnel over 2 hours. After the dropping was completed, the resulting mixture was further stirred at 65 ° C. for 2 hours. After the reaction was completed, 40 g of methanol was added to the mixture, the mixture was cooled, and the resulting mixture was added to 2 liters of water while stirring this water, the mixture was stirred for 30 minutes, and then the precipitate was taken out by filtration and dried. Gave 15 g of a white solid. The weight average molecular weight (polystyrene standard) of the specific copolymer was measured by gel permeation chromatography and found to be 53,000.

The following coating solution for image forming layer was applied on the obtained support and dried at 150 ° C. for 30 seconds to a dry coating amount of 1.8 g / m ² to obtain a positive lithographic printing plate precursor. It was <Coating Liquid for Image Forming Layer> Specific Copolymer 1 [(B) Component] 0.4 g m, p-cresol novolac [(B) Component] 0.6 g (m / p ratio = 6/4, weight Cyanine dye A [(A + C) component] 0.1 g Phthalic anhydride [(D) component] 0.05 g p-toluenesulfonic acid 0.002 g ethyl violet 0.1. 02 g (counter ion: 6-hydroxy-β-naphthalene sulfonic acid) Naphtoquinone 1,2-diazide-5-sulfonyl chloride ester product with pyrogallol-acetone resin 0.01 g Fluorine-based surfactant 0.05 g (trade name: Megafac F-177, manufactured by Dainippon Ink and Chemicals, Inc. Methyl ethyl ketone 8 g 1-methoxy-2-propanol 4 g

Output 5 on the lithographic printing plate precursor obtained as described above.
00 mW, wavelength 830 nm, beam diameter 17 μm (1 /
It was exposed at a main scanning speed of 5 m / sec using the semiconductor laser of e ² ) and kept at 25 ° C. This planographic printing plate original,
Automatic developing machine P filled with the above alkaline developing solutions
Development processing was performed with S900NP (manufactured by Fuji Photo Film Co., Ltd.) at a development temperature of 30 ° C. for 12 seconds. 50m ² , 100m ² , 200m ² , 300m ² , 40 without replenishment
It was treated with 0 m ² and 500 m ² . After the development processing was completed, a washing process was performed, followed by processing with gum (GU-7 (1: 1)) or the like to obtain a lithographic printing plate on which plate making was completed.

<Evaluation of balance between image area / non-image area> (Evaluation of developability of non-image area) Immediately after development as described above, 50 m ² , 100 m ² , 200 m ² , 300 m ² , 40
By observing the "presence or absence of residual film in non-image area" of the developability of the non-image area of the lithographic printing plate obtained by treating with 0 m ² and 500 m ² ,
Sensory evaluation was performed. The results are shown in Tables 2 and 3. -Criteria- A: Sufficiently developed, no residual image forming layer on the non-image area was observed. There was no stain on the print. Δ: The image forming layer was slightly left on the non-image area. There was no stain on the print. X: Poor development was recognized, and the image forming layer remained in the non-image area. Dirt has occurred on the printed matter.

<Evaluation of Film Roughness in Image Area> Immediately after development as described above, immediately after development, 50 m ² , 100 m ² , 200 m ² , 300
The “defects in the image area” of the lithographic printing plate obtained by treating with m ² , 400 m ² and 500 m ² were visually observed according to the following criteria to perform sensory evaluation. The evaluation results are shown in Tables 4 to 5. -Reference- ○: No defect was observed in the image area. There was no white spot in the image area on the printed matter. Δ: The image area density was slightly reduced, and some defects were recognized. On the printed matter, there was no white spot in the image area. X: The density of the image area is significantly reduced, and the image area has a defect. White spots in the image area occurred on the printed matter.

[0126]

[Table 2]

[0127]

[Table 3]

[0128]

[Table 4]

[0129]

[Table 5]

[0130]

Examples 21-40 and Comparative Examples 3 and 4 Examples 21-
40 and the infrared-sensitive lithographic printing plates used in Comparative Examples 3 and 4 were prepared in the following manner and treated as alkaline developing solutions (1) to (10) in Examples 21 to 30, respectively.
1 to 40, respectively, alkaline developing solution (11) to (20)
And alkali developing solutions (21) and (22) as Comparative Examples 3 and 4, respectively.

<Preparation of lithographic printing plate precursor 2> The following photosensitive solution 2 was coated on an aluminum support which was treated in the same manner as in <Preparation 1 of lithographic printing plate precursor> and provided with an undercoat layer. To 0.16 g / m ² with a wire bar, then use TABAI PERFECT OVER PH 200 to make WindCo
The ntrol was set to 7 and dried at 140 ° C. for 50 seconds. Further, the photosensitive solution 3 is applied thereon by a wire bar so that the applied amount becomes 0.85 g / m ^2, and then PERFECT OVER P manufactured by TABAI.
Wind Control was set to 7 on H200 and dried at 120 ° C. for 60 seconds to obtain a lithographic printing plate precursor having a heat-sensitive layer having a two-layer structure.

[0132] (Photosensitive liquid 2) N- (4-aminosulfonylphenyl) methacrylamide /   Acrylonitrile / methyl methacrylate   (36/34/30 weight average molecular weight 50,000) 1.896g Cresol novolac (m / p = 6/4 weight average molecular weight 4500,   Residual monomer 0.8wt%) 0.237g Cyanine dye A 0.109g 4,4'-bishydroxyphenyl sulfone 0.063g Tetrahydrophthalic anhydride 0.190g p-toluenesulfonic acid 0.008 g The counter ion of ethyl violet   Changed to 6-hydroxynaphthalene sulfone 0.05g Fluorosurfactant (F176, manufactured by Dainippon Ink and Co., Ltd.) 0.035 g Methyl ethyl ketone 26.6g 1-methoxy-2-propanol 13.6g γ-butyrolactone 13.8 g

[0133] (Photosensitive liquid 3) Cresol novolac (m / p = 6/4 weight average molecular weight 4500,   Residual monomer 0.8wt%) 0.237g Cyanine dye A 0.047g Dodecyl stearate 0.060g 3-methoxy-4-diazodiphenylamine hexafluorophosphate                                                         0.030g Fluorine-based surfactant (F176 (20% solution), manufactured by Dainippon Ink and Chemicals, Inc.)                                                         0.110 g Fluorine-based surfactant (MCF312F (30% solution), manufactured by Dainippon Ink and Chemicals, Inc.)                                                         0.12g Methyl ethyl ketone 15.1 g 1-Methoxy-2-propanol 7.7g

Output 5 on the lithographic printing plate precursor obtained from the above.
00 mW, wavelength 830 nm, beam diameter 17 μm (1 /
It was exposed at a main scanning speed of 5 m / sec using the semiconductor laser of e ² ) and kept at 25 ° C. This planographic printing plate original,
Automatic developing machine P filled with the above alkaline developing solutions
Development processing was performed with S900NP (manufactured by Fuji Photo Film Co., Ltd.) at a development temperature of 30 ° C. for 12 seconds. 50m ² , 100m ² , 200m ² , 300m ² , 40 without replenishment
It was treated with 0 m ² and 500 m ² . After the development processing was completed, a washing process was performed, followed by processing with gum (GU-7 (1: 1)) or the like to obtain a lithographic printing plate on which plate making was completed.

Regarding the lithographic printing plate thus prepared,
In the same manner as in Examples 1 to 60, the developability in the non-image area and the film slippage in the image area were evaluated. The evaluation results are shown in Tables 6 to 7 for the developability of the non-image area and in Tables 8 to 9 for the film slip of the image area.

[0136]

[Table 6]

[0137]

[Table 7]

[0138]

[Table 8]

[0139]

[Table 9]

Claims (2)

[Claims] 1. An alkaline developing treatment solution for infrared-sensitive lithographic printing plates, which contains soybean polysaccharide. 2. A plate-making method for a lithographic printing plate, which comprises exposing an infrared-sensitive lithographic printing plate having an image forming layer containing an infrared absorber to infrared rays and then developing the plate with the alkaline developing solution according to claim 1.