JP2015132837A - Method for making lithographic printing plate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method capable of obtaining a lithographic printing plate excellent in printing durability and suppressing the odor of a developer and the occurrence of development sludge due to a component removed by development and a method for making a lithographic printing plate which is excellent in sensitivity and developability.SOLUTION: A method for making a lithographic printing plate comprises: a step of preparing a negative lithographic printing plate precursor having a photopolymerizable photosensitive layer on a support; a step of imagewise exposing the negative lithographic printing plate precursor; and a step of developing the exposed negative lithographic printing plate precursor with a developer containing at least (component A) a compound represented by the following formula (I), (component B) a compound represented by the following formula (II) and (component C) water.

Description

  The present invention relates to a method for making a lithographic printing plate.

In general, a lithographic printing plate comprises an oleophilic image area that receives ink in the printing process and a hydrophilic non-image area that receives dampening water. Lithographic printing utilizes the property that water and oil-based inks repel each other, so that the oleophilic image area of the lithographic printing plate is the ink receiving area and the hydrophilic non-image area is dampened with the water receiving area (ink non-receiving area). As described above, a difference in ink adhesion is caused on the surface of a lithographic printing plate, and after ink is applied only to an image portion, the ink is transferred to a printing medium such as paper and printed.
In order to produce this lithographic printing plate, a lithographic printing plate precursor (PS plate) in which an oleophilic photosensitive resin layer (photosensitive layer) is provided on a hydrophilic support has been widely used. Usually, the lithographic printing plate precursor is exposed through an original image such as a lithographic film, and then the photosensitive layer corresponding to the image area is left, and the unnecessary photosensitive layer corresponding to the non-image area is strongly alkaline with a pH of 12 or more. The lithographic printing plate is obtained by dissolving and removing with a developer and exposing the surface of the hydrophilic support to form a non-image portion to form a non-image portion.
In the conventional lithographic printing plate preparation process, after exposure, a process of dissolving and removing unnecessary photosensitive layers with a developer or the like is necessary. However, such additional wet processing can be simplified. It is listed as one of the issues. In particular, disposal of the waste liquid discharged with high pH alkaline development processing has become a major concern for the entire industry in recent years due to consideration for the global environment. It is more strongly desired to be able to develop with an aqueous solution.

On the other hand, in recent years, digitization technology for electronically processing, storing, and outputting image information by a computer has become widespread, and various new image output methods corresponding to such digitization technology will be put into practical use. It is becoming. Along with this, digitized image information is carried by high-convergence radiation such as laser light, and the lithographic printing plate precursor is scanned and exposed with that light, directly without using a lithographic film. Computer-to-plate (CTP) technology has been attracting attention. Therefore, obtaining a lithographic printing plate precursor adapted to such a technique is one of the important technical issues.
As laser light sources used in the above-mentioned CTP technology, solid lasers such as semiconductor lasers and YAG lasers that emit infrared light with a wavelength of 760 to 1,200 nm can be obtained at low cost with high output and small size. Is extremely useful. A UV laser can also be used.

From the background as described above, it is now more strongly desired than ever to adapt both the simplification of the plate making operation and the digitization.
On the other hand, for example, in Patent Document 1, a lithographic printing plate precursor in which a photosensitive layer in which hydrophobic thermoplastic polymer particles are dispersed in a hydrophilic binder is provided on a hydrophilic support is developed with a gum solution. The plate making method is described.
Patent Document 2 discloses a lithographic printing plate precursor comprising a photosensitive layer containing (i) a hydrophilic support and (ii) a radical polymerizable ethylenically unsaturated monomer, a radical polymerization initiator and an infrared absorbing dye. A method for processing a lithographic printing plate precursor is described in which an uncured portion of the photosensitive layer is removed with a gum solution after imagewise exposure with an external laser.
Further, in Patent Document 3, the radical polymerization type photosensitive layer is cured by infrared laser exposure, and the unexposed portion is removed with a solvent-containing developer having a pH of less than 12 and containing benzyl alcohol and an amphoteric surfactant having a specific structure. A method for developing a lithographic printing plate precursor is described.
Further, in Patent Document 4, a radical polymerization type photosensitive layer is cured by infrared laser exposure, and contains 60 wt% or less of water, a water-soluble or water-dispersible solvent, and a surfactant having a specific structure. A method for developing a lithographic printing plate precursor comprising removing unexposed portions with a developer is described.

European Patent No. 1342568 International Publication No. 05/111727 Pamphlet International Publication No. 08/027227 Pamphlet US Patent Application Publication No. 2010/0216067

In the plate making method described in Patent Document 1, the lithographic printing plate precursor is subjected to image exposure using an infrared laser to form an image by fusing hydrophobic thermoplastic polymer particles, and then using a gum solution. Development is performed by removing unexposed portions.
However, the method of developing a lithographic printing plate precursor using image formation by thermal fusion of such fine particles with a gum solution has very good developability but low sensitivity and printing durability, and is unexposed. Since the removed fine particles easily aggregate and settle in the developer, there is a big problem that sludge deposits called development sludge are generated.
Further, the developers in the inventions described in Patent Documents 3 and 4 contain an organic solvent and are inferior in terms of work safety, but these enable low pH development and are excellent in environmental considerations and image formation. Although the sensitivity and printing durability are high due to the use of radical polymerization, the photosensitive layer components after development removal still aggregate and settle in the developer, resulting in poor development sludge and developer circulation. There is a problem that the frequency of replacement of the filter in the system is remarkably increased, and further, the time required for cleaning the developing bath at the time of replacement of the developer becomes long.

  Accordingly, an object of the present invention is to obtain a lithographic printing plate excellent in printing durability, to be able to suppress development odor and development sludge caused by a development removal component, and to be excellent in sensitivity and developability. It is to provide a plate making method.

The above object has been achieved by the means described in <1> below. It shows below with <2>-<25> which is a preferable embodiment.
<1> A step of producing a negative lithographic printing plate precursor having a photopolymerizable photosensitive layer on a support, a step of imagewise exposing the negative lithographic printing plate precursor, (Component A) in the following formula (I) A step of developing the negative lithographic printing plate precursor exposed with a developer containing at least a compound represented by (Component B) a compound represented by the following formula (II) and (Component C) water: The plate making method of lithographic printing plate,

（式中、Ｒ¹は炭素数４〜８の直鎖又は分岐したアルキル基を表し、Ｒ²及びＲ³はそれぞれ独立に、水素原子又はメチル基を表し、かつＲ²及びＲ³のいずれか一方がメチル基の場合他方は水素原子であり、ｎは１又は２を表し、Ｒ⁴は置換若しくは無置換の、フェニル基、１−ナフチル基又は２−ナフチル基を表し、ｍは４〜２０の整数を表す。）

(In the formula, R ¹ represents a linear or branched alkyl group having 4 to 8 carbon atoms, R ² and R ³ each independently represents a hydrogen atom or a methyl group, and any one of R ² and R ³ When one is a methyl group, the other is a hydrogen atom, n represents 1 or 2, R ⁴ represents a substituted or unsubstituted phenyl group, 1-naphthyl group or 2-naphthyl group, and m is 4 to 20 Represents an integer.)

<2> The plate-making method of a lithographic printing plate according to <1>, wherein n is 1;
<3> The plate making method of a lithographic printing plate as described in <1> or <2> above, wherein both R ² and R ³ are hydrogen atoms,
<4> The plate making method of a lithographic printing plate according to any one of the above <1> to <3>, wherein R ¹ is an n-butyl group, an n-hexyl group or a 2-ethylhexyl group,
<5> The method for making a lithographic printing plate according to any one of <1> to <4>, wherein Component A is a compound having an octanol / water partition coefficient of 0.8 to 2.0,
<6> Component A is a compound selected from the group consisting of ethylene glycol mono n-butyl ether, ethylene glycol mono n-hexyl ether, and propylene glycol mono n-butyl ether. A plate making method of a lithographic printing plate according to any one of the above,
<7> The lithographic printing plate according to any one of <1> to <6>, wherein the content of component A in the developer exceeds the solubility of component A in water and is 40% by weight or less. Plate making method,
<8> The process for making a lithographic printing plate according to any one of the above <1> to <6>, wherein the content of component A in the developer is 2 to 30% by weight,
<9> The plate making method of a lithographic printing plate according to <8>, wherein the content of component A in the developer is 5 to 20% by weight,
<10> The plate making method of a lithographic printing plate according to any one of the above <1> to <9>, wherein R ⁴ is a substituted or unsubstituted 1-naphthyl group or 2-naphthyl group,

<11> The plate-making method of a lithographic printing plate according to any one of <1> to <10>, wherein m is 9 to 16,
<12> The lithographic plate according to any one of <1> to <11>, wherein the content of component B in the developer is 20 wt% or less and an amount capable of solubilizing component A Plate making method of printing plate,
<13> The plate making method of a lithographic printing plate according to any one of the above <1> to <11>, wherein the content of component B in the developer is 1 to 15% by weight,
<14> The plate-making method of a lithographic printing plate according to <13>, wherein the content of component B in the developer is 4 to 10% by weight,
<15> The plate making method of a lithographic printing plate according to any one of the above <1> to <14>, wherein the content of component C in the developer is 50% by weight or more,
<16> The plate-making method of a lithographic printing plate according to any one of the above <1> to <15>, wherein the developer further contains an anionic surfactant or an amphoteric surfactant,
<17> The plate-making method of a lithographic printing plate according to any one of the above <1> to <16>, wherein the developer has a pH of 6 to 8,
<18> The plate making method of a lithographic printing plate according to any one of the above <1> to <17>, wherein the photopolymerizable photosensitive layer contains an acrylic polymer having a monomer unit derived from a vinyl carbazole compound.
<19> The plate-making method of a lithographic printing plate according to <18>, wherein the acrylic polymer further contains a monomer unit derived from acrylonitrile,
<20> The method for making a lithographic printing plate according to any one of <1> to <19>, wherein the photopolymerizable photosensitive layer contains a urethane-acrylic hybrid polymer,

<21> The urethane-acrylic hybrid polymer according to <20>, wherein the urethane-acrylic hybrid polymer has a monomer unit derived from a compound selected from the group consisting of diphenylmethane diisocyanate, m-tolylene diisocyanate, isophorone diisocyanate, and dicyclohexylmethane diisocyanate. Plate making method of lithographic printing plate,
<22> The photopolymerizable photosensitive layer according to any one of the above <1> to <21>, wherein the photopolymerizable photosensitive layer is sensitive to infrared light and contains a triphenylalkyl borate salt or a tetraphenylborate salt. Plate making method of lithographic printing plate,
<23> The method for making a lithographic printing plate according to <22>, wherein the photopolymerizable photosensitive layer further contains a copper phthalocyanine pigment,
<24> The lithographic plate according to any one of <1> to <21>, wherein the photopolymerizable photosensitive layer is infrared-sensitive, does not contain a borate salt, and contains a colored dye. Plate making method of printing plate,
<25> The method for making a lithographic printing plate as described in any one of <22> to <24>, wherein the photopolymerizable photosensitive layer contains a cyanine dye and an iodonium salt.

  According to the present invention, it is possible to obtain a lithographic printing plate having excellent printing durability, making it possible to suppress the odor of the developer and development sludge due to the development removal component, and making the lithographic printing plate excellent in sensitivity and developability. Could provide a way.

It is a figure which shows the structure of an example of the automatic image development apparatus of the lithographic printing plate precursor which can be used suitably for the plate-making method of the lithographic printing plate of this invention. It is a figure which shows the structure of an example of the automatic image development apparatus only of the image development part which can be used suitably for the plate-making method of the lithographic printing plate of this invention.

  The plate making method of the lithographic printing plate of the present invention comprises a step of producing a negative lithographic printing plate precursor having a photopolymerizable photosensitive layer on a support (hereinafter also referred to as “original plate producing step”), the negative lithographic printing. Step of exposing the plate precursor imagewise (hereinafter also referred to as “exposure step”), (Component A) Compound represented by the following formula (I), (Component B) Compound represented by the following formula (II) And (Component C) a step of developing the negative lithographic printing plate precursor exposed with a developer containing at least water (hereinafter also referred to as “developing step”).

（式中、Ｒ¹は炭素数４〜８の直鎖又は分岐したアルキル基を表し、Ｒ²及びＲ³はそれぞれ独立に、水素原子又はメチル基を表し、かつＲ²及びＲ³のいずれか一方がメチル基の場合他方は水素原子であり、ｎは１又は２を表し、Ｒ⁴は置換若しくは無置換の、フェニル基、１−ナフチル基又は２−ナフチル基を表し、ｍは４〜２０の整数を表す。）

(In the formula, R ¹ represents a linear or branched alkyl group having 4 to 8 carbon atoms, R ² and R ³ each independently represents a hydrogen atom or a methyl group, and any one of R ² and R ³ When one is a methyl group, the other is a hydrogen atom, n represents 1 or 2, R ⁴ represents a substituted or unsubstituted phenyl group, 1-naphthyl group or 2-naphthyl group, and m is 4 to 20 Represents an integer.)

Hereinafter, the plate making method of the planographic printing plate of the present invention will be described in detail. In the present invention, after the development process, which is the most characteristic process, is described, other processes are described.
In the present invention, the description of “lower limit to upper limit” representing a numerical range represents “more than the lower limit and less than or equal to the upper limit”, and the description of “upper limit to lower limit” represents “the upper limit or less and less than the lower limit”. That is, it represents a numerical range including an upper limit and a lower limit. Further, “(component A) compound represented by formula (I)” or the like is also simply referred to as “component A” or the like.

(Development process)
The lithographic printing plate making method of the present invention comprises (Component A) a compound represented by Formula (I), (Component B) a compound represented by Formula (II), and (Component C) development containing at least water. A step (developing step) of developing the negative lithographic printing plate precursor exposed by the liquid.

<Developer>
The developer used in the lithographic printing plate making method of the present invention is an aqueous solution or aqueous dispersion containing at least the components A to C.
The developer is a single-phase (not separated) component A which is an organic solvent having a specific structure is solubilized in component C water by a component B which is a nonionic surfactant having a specific structure. An aqueous solution or an aqueous dispersion is preferred.
(Component A) The compound represented by the formula (I) in the developer is a developing agent responsible for removing an unexposed portion of the lithographic printing plate precursor, and in the developer of the photosensitive layer that has been developed and removed. Can be imparted (development sludge suppression). When component A is used alone as a developing solution, the solvent odor is extremely strong and the environment around the developing device deteriorates, so that the amount used can be reduced and the solvent exposure on the surface of the solution can be reduced. In the developer used in the above, (Component C) is used by mixing with water. At this time, if a compound that is highly compatible with water is used, the organic solvent can exist stably in water, so even if the developer is brought into contact with the lithographic printing plate precursor surface, the organic solvent remains in the photosensitive layer of the lithographic printing plate precursor. Difficult to penetrate and developability becomes insufficient. Therefore, as the compound represented by (Component A) formula (I), a compound having low compatibility with water is used, preferably mixed in an amount more than the solubility in water, and this is mixed with (Component B) formula (II). Component A which is a developing agent can be obtained by solubilizing in water with a compound represented by formula (1) and greatly reducing the solvent odor and destroying the oil in water micelles when contacting the lithographic printing plate precursor surface. Penetrates into the photosensitive layer and can be developed. In addition, the compound represented by (Component B) formula (II) is also considered to have a function of suppressing development sludge.
Hereinafter, components A to C will be described.

(Component A) Compound Represented by Formula (I) Component A is a compound represented by the following formula (I). Further, the compound represented by the formula (I) preferably functions as an organic solvent for dissolving and / or dispersing development sludge resulting from the development removal component in the developer in the developer.

（式中、Ｒ¹は炭素数４〜８の直鎖又は分岐したアルキル基を表し、Ｒ²及びＲ³はそれぞれ独立に、水素原子又はメチル基を表し、かつＲ²及びＲ³のいずれか一方がメチル基の場合他方は水素原子であり、ｎは１又は２を表す。）

(In the formula, R ¹ represents a linear or branched alkyl group having 4 to 8 carbon atoms, R ² and R ³ each independently represents a hydrogen atom or a methyl group, and any one of R ² and R ³ When one is a methyl group, the other is a hydrogen atom, and n represents 1 or 2.)

N in the formula (I) is preferably 1. R ² and R ³ are preferably both hydrogen atoms. R ¹ is preferably an n-butyl group, an n-hexyl group, or a 2-ethylhexyl group, and more preferably an n-hexyl group. In the above embodiment, development sludge caused by the development removal component can be further suppressed, and the developability is further improved.
Specific examples of component A include ethylene glycol mono n-butyl ether, ethylene glycol mono n-hexyl ether, ethylene glycol mono t-butyl ether, diethylene glycol mono-2-ethylhexyl ether, and propylene glycol mono n-butyl ether. It is preferably a selected compound, more preferably a compound selected from the group consisting of ethylene glycol mono n-butyl ether, ethylene glycol mono n-hexyl ether, and propylene glycol mono n-butyl ether. More preferably, it is mono n-hexyl ether.

Moreover, it is preferable that the component A has an octanol / water partition coefficient of 0.8-2.0 as one of the physical characteristics. The octanol / water partition coefficient is the concentration ratio of chemical substances in the two phases when a chemical substance is added to the two solvent phases of 1-octanol and water to achieve an equilibrium state. It is a physicochemical index that expresses the property (easiness to dissolve in lipid), and the larger the value, the higher the hydrophobicity. The octanol / water partition coefficient may be described by the abbreviation Pow, and may also be generally described by a logarithmic value (LogP).
The compound having the above octanol / water partition coefficient has a characteristic of relatively low water solubility, and the developer used in the present invention may contain component A in an amount greater than the solubility in water. preferable. In this case, the component A having a solubility or higher is separated from the aqueous solution into two phases, but a form in which the component A is solubilized with the component B described later to form a single-phase aqueous solution or aqueous dispersion is preferable. When the component A is contained in the developer in an amount equal to or higher than its solubility in water, the odor of the developer and the development sludge due to the development removal component can be further suppressed, and the developability is further improved.

Component A is preferably in an amount of 40% by weight or less in the developer. When it is 40% by weight or less, a developer in the state of oil in water (o / w) in which component A is solubilized in component B in water can be easily obtained, and there is little organic solvent odor and excellent work safety. The content of Component A is more preferably 2 to 30% by weight in the developer, and most preferably 5 to 20% by weight in the developer.
Component A may be used alone or in combination of two or more.

(Component B) Compound Represented by Formula (II) Component B is a compound represented by the following formula (II). Moreover, it is preferable that the compound represented by the formula (II) functions as a nonionic surfactant that contributes to the dispersion of developer sludge caused by component A and the developer removal component in the developer in the developer.

（式中、Ｒ⁴は置換若しくは無置換の、フェニル基、１−ナフチル基又は２−ナフチル基を表し、ｍは４〜２０の整数を表す。）

(In the formula, R ⁴ represents a substituted or unsubstituted phenyl group, 1-naphthyl group or 2-naphthyl group, and m represents an integer of 4 to 20).

R ^{4 in the} formula (II) is preferably a substituted or unsubstituted 1-naphthyl group or 2-naphthyl group, more preferably a 1-naphthyl group or a 2-naphthyl group. More preferably, it is a 1-naphthyl group. Moreover, m is preferably 9-16, and more preferably 11-16.
Preferred examples of the substituent in the phenyl group, 1-naphthyl group, or 2-naphthyl group of R ⁴ include an alkyl group, an aryl group, and an aralkyl group.
Specific examples of component B include, but are not limited to, the following structures.

  Among these, as component B, B-12 to B-15 are preferable, and B-14 is particularly preferable.

  In addition, the component B includes “Emulgen A” series, “Emulgen B” series manufactured by Kao Corporation, “Naroacty CL” series manufactured by Sanyo Chemical Industries, Ltd., “New Coal 700” series manufactured by Nippon Emulsifier Co., Ltd., They are available as commercial products such as “New Call 2600” series and “New Call B” series.

Component B preferably contains at least an amount capable of solubilizing component A in the developer. By solubilizing component A in water, the odor of the organic solvent can be suppressed, and the development of the lithographic printing plate can be suppressed from becoming uneven. Component B is preferably 20% by weight or less in the developer. When the content is 20% by weight or less, the solubilized organic solvent has an appropriate stability in the developer, and the micelle breakage is easy even on the surface of the lithographic printing plate precursor, and the developability is excellent.
Component B is more preferably contained in the developer in an amount of 1 to 15% by weight, and most preferably 4 to 10% by weight in the developer.
Component B may be used in combination of two or more.

(Component C) Water Component C is water.
Here, water refers to pure water, distilled water, ion exchange water, tap water, and the like, and water of any hardness can be used.
The content of component C in the developer is preferably 50% by weight or more in order to maintain the oil in water micelle structure as described above.

The other components in the developer are described below.
The developer may contain other surfactant (anionic, nonionic, cationic, amphoteric, etc.) in addition to the component (Component B) represented by the formula (II).
It does not specifically limit as an anionic surfactant which can be used for this invention, A conventionally well-known thing can be used. For example, fatty acid salts, abietic acid salts, hydroxyalkane sulfonates, alkane sulfonates, dialkyl sulfosuccinates, linear alkyl benzene sulfonates, branched alkyl benzene sulfonates, alkyl naphthalene sulfonates, alkyl phenoxy polyoxyethylene Propyl sulfonates, polyoxyethylene alkyl sulfophenyl ether salts, N-methyl-N-oleyl taurine sodium, N-alkyl sulfosuccinic acid monoamide disodium salts, petroleum sulfonates, sulfated castor oil, sulfated beef oil, Fatty acid alkyl ester sulfate ester salt, alkyl sulfate ester salt, polyoxyethylene alkyl ether sulfate ester salt, fatty acid monoglyceride sulfate ester, polyoxy Tylene alkylphenyl ether sulfate ester salt, polyoxyethylene styryl phenyl ether sulfate ester salt, alkyl phosphate ester salt, polyoxyethylene alkyl ether phosphate ester salt, polyoxyethylene alkylphenyl ether phosphate ester salt, styrene-maleic anhydride copolymer And olefin-maleic anhydride copolymer partial saponification products, naphthalene sulfonate formalin condensates, aromatic sulfonates, aromatic substituted polyoxyethylene sulfonates, and the like. Among these, dialkyl sulfosuccinates, alkyl sulfate esters and / or alkyl naphthalene sulfonates are particularly preferably used.

  The cationic surfactant that can be used in the present invention is not particularly limited, and conventionally known cationic surfactants can be used. Examples thereof include alkylamine salts, quaternary ammonium salts, polyoxyethylene alkylamine salts, and polyethylene polyamine derivatives.

  Examples of other nonionic surfactants that can be used in the present invention include polyethylene glycol type higher alcohol ethylene oxide adducts, fatty acid ethylene oxide adducts, polyhydric alcohol fatty acid ester ethylene oxide adducts, and higher alkylamine ethylenes. Oxide adduct, fatty acid amide ethylene oxide adduct, fat and oil ethylene oxide adduct, polypropylene glycol ethylene oxide adduct, dimethylsiloxane-ethylene oxide block copolymer, dimethylsiloxane- (propylene oxide-ethylene oxide) block copolymer, etc. Alcohol-type fatty acid ester of glycerol, fatty acid ester of pentaerythritol, fatty acid ester of sorbitol and sorbitan, Fatty acid esters of sugars, alkyl ethers of polyhydric alcohols, fatty acid amides of alkanolamines. Also, acetylene glycol-based and acetylene alcohol-based oxyethylene adducts, fluorine-based and silicone-based surfactants can be used in the same manner.

  The amphoteric surfactant that can be used in the present invention is not particularly limited, and conventionally known amphoteric surfactants can be used. Examples thereof include amphoteric surfactants such as amino acids, betaines, and amine oxides.

These other surfactants can be used singly or in combination of two or more.
The content of the other surfactant in the developer is preferably 0.01 to 10% by weight, and more preferably 0.01 to 5% by weight.

  For the purpose of assisting pH adjustment and dissolution of the non-image area photosensitive layer, an alkali agent may be additionally included. Examples of the alkali agent include carbonates or hydrogen carbonates and organic alkali agents. The carbonate and bicarbonate are not particularly limited, but are preferably alkali metal salts. Examples of the alkali metal include lithium, sodium, and potassium, and sodium is particularly preferable. Organic alkali agents include monomethylamine, dimethylamine, trimethylamine, monoethylamine, diethylamine, triethylamine, monoisopropylamine, diisopropylamine, triisopropylamine, n-butylamine, monoethanolamine, diethanolamine, triethanolamine, monoisopropanol Examples thereof include amines, diisopropanolamine, ethyleneimine, ethylenediamine, pyridine, and tetramethylammonium hydroxide. These alkaline agents are used alone or in combination of two or more.

  The pH of the developer is not particularly limited, but is preferably in the range of 6 to 8 from the viewpoints of environmental considerations and work safety.

For the purpose of protecting the surface of the non-image area after developing and removing the photosensitive layer, the developer may contain a water-soluble polymer compound.
Examples of water-soluble polymer compounds that can be used in the present invention include soybean polysaccharide, starch, gum arabic, dextrin, fiber derivatives (eg, carboxymethylcellulose, carboxyethylcellulose, methylcellulose, etc.) and modified products thereof, pullulan, polyvinyl alcohol, and the like. Examples thereof include polyvinyl pyrrolidone, polyacrylamide and acrylamide copolymers, vinyl methyl ether / maleic anhydride copolymers, vinyl acetate / maleic anhydride copolymers, styrene / maleic anhydride copolymers, and the like.
A preferable acid value of the water-soluble polymer compound is 0 to 3.0 meq / g.

  As said soybean polysaccharide, what is known conventionally can be used, for example, there is Soya Five (made by Fuji Oil Co., Ltd.) as a commercial item, and various grades can be used. What can be preferably used is one in which the viscosity of a 10 wt% aqueous solution is in the range of 10 to 100 mPa / sec.

Examples of the starch include candied starch, potato starch, tapioca starch, wheat starch and corn starch, and these modified starches and starch derivatives.
The modified starch can be produced by a method of decomposing within 5 to 30 glucose residues per molecule with an acid or an enzyme, and further adding oxypropylene in an alkali.
As starch derivatives, roasted starch such as British gum, enzyme-modified dextrins such as enzyme dextrin and shardinger dextrin, oxidized starch shown in solubilized starch, pregelatinized starch such as modified pregelatinized starch and non-modified pregelatinized starch, Esterified starch such as phosphate starch, fat starch, sulfate starch, nitrate starch, xanthate starch and carbamic acid starch, carboxyalkyl starch, hydroxyalkyl starch, sulfoalkyl starch, cyanoethyl starch, allyl starch, benzyl starch, carbamylethyl Starch, etherified starch such as dialkylamino starch, methylol cross-linked starch, hydroxyalkyl cross-linked starch, phosphoric acid cross-linked starch, cross-linked starch such as dicarboxylic acid cross-linked starch, starch polyacrylamide copolymer, starch polyacrylic acid copolymer, starch Polyacetic acid Nyl copolymer, starch polyacrylonitrile copolymer, chaotic starch polyacrylic acid ester copolymer, chaotic starch vinyl polymer copolymer, starch polystyrene maleic acid copolymer, starch polyethylene oxide copolymer, starch polypropylene copolymer Starch graft polymers such as polymers are preferred.

Among the water-soluble polymer compounds, soybean polysaccharide, starch, gum arabic, dextrin, carboxymethyl cellulose or polyvinyl alcohol is preferable, and gum arabic or starch is more preferable.
Two or more water-soluble polymer compounds can be used in combination.
The content of the water-soluble polymer compound in the developer is preferably from 0.1 to 20% by weight, and more preferably from 0.5 to 10% by weight.

  In addition to the above, the developer may contain a wetting agent, preservative, chelate compound, antifoaming agent, organic acid, inorganic acid, inorganic salt, and the like.

As the wetting agent, ethylene glycol, propylene glycol, triethylene glycol, butylene glycol, hexylene glycol, diethylene glycol, dipropylene glycol, glycerin, trimethylolpropane, diglycerin and the like are preferably used.
One wetting agent may be used alone, or two or more wetting agents may be used in combination.
The wetting agent is preferably used in an amount of 0.1 to 5% by weight based on the total weight of the developer.

Preservatives include phenol or derivatives thereof, formalin, imidazole derivatives, sodium dehydroacetate, 4-isothiazolin-3-one derivatives, benzoisothiazolin-3-one, 2-methyl-4-isothiazolin-3-one, benztriazole derivatives Amiding anidine derivatives, quaternary ammonium salts, derivatives such as pyridine, quinoline, guanidine, diazine, triazole derivatives, oxazole, oxazine derivatives, nitrobromoalcohol-based 2-bromo-2-nitropropane-1,3-diol, 1,1-dibromo-1-nitro-2-ethanol, 1,1-dibromo-1-nitro-2-propanol and the like can be preferably used. It is preferable to use two or more kinds of preservatives in combination so as to be effective against various molds and sterilization.
The content of the preservative is an amount that exhibits a stable effect on bacteria, mold, yeast, and the like, and varies depending on the type of bacteria, mold, yeast, but 0.01 to 4 relative to the developer. A range of% by weight is preferred.

Examples of the chelate compound include ethylenediaminetetraacetic acid, potassium salt thereof, sodium salt thereof; diethylenetriaminepentaacetic acid, potassium salt thereof, sodium salt thereof; triethylenetetraminehexaacetic acid, potassium salt thereof, sodium salt thereof, hydroxyethylethylenediaminetriacetic acid Nitrilotriacetic acid, sodium salt; 1-hydroxyethane-1,1-diphosphonic acid, potassium salt, sodium salt; aminotri (methylenephosphonic acid), potassium salt, sodium salt And organic phosphonic acids and phosphonoalkanetricarboxylic acids. Organic amine salts are also effective in place of the sodium and potassium salts of the chelating agents.
A chelating agent is preferably selected that is stably present in the developer and does not impair the printability.
The content of the chelating agent is preferably 0.001 to 1.0% by weight with respect to the total weight of the developer.

As the antifoaming agent, a general silicone-based self-emulsifying type, emulsifying type, nonionic HLB (Hydrophile-Lipophile Balance) 5 or less compound can be used. Silicone defoamers are preferred. Among them, emulsification dispersion type and solubilization can be used.
The content of the antifoaming agent is preferably in the range of 0.001 to 1.0% by weight with respect to the total weight of the developer.

Examples of the organic acid include citric acid, acetic acid, succinic acid, malonic acid, salicylic acid, caprylic acid, tartaric acid, malic acid, lactic acid, levulinic acid, p-toluenesulfonic acid, xylenesulfonic acid, phytic acid, and organic phosphonic acid. . The organic acid can also be used in the form of its alkali metal salt or ammonium salt.
The content of the organic acid is preferably 0.01 to 0.5% by weight with respect to the total weight of the developer.

Examples of inorganic acids and inorganic salts include phosphoric acid, metaphosphoric acid, primary ammonium phosphate, secondary ammonium phosphate, primary sodium phosphate, secondary sodium phosphate, primary potassium phosphate, secondary potassium phosphate, Examples include sodium tripolyphosphate, potassium pyrophosphate, sodium hexametaphosphate, magnesium nitrate, sodium nitrate, potassium nitrate, ammonium nitrate, sodium sulfate, potassium sulfate, ammonium sulfate, sodium sulfite, ammonium sulfite, sodium hydrogen sulfate, nickel sulfate and the like.
The content of the inorganic acid and the inorganic salt is preferably 0.01 to 0.5% by weight with respect to the total weight of the developer.

  The development process in the development step is not particularly limited and may be performed by a known method, but is preferably performed using an automatic processor equipped with a rubbing member. Further, the development processing can be suitably performed by an automatic processor equipped with a supply means such as the developer. Examples of the automatic processor include an automatic processor described in Japanese Patent Application Laid-Open No. 2006-235227 that performs rubbing while conveying a lithographic printing plate precursor after image recording. Among these, an automatic processor using a rotating brush roll as the rubbing member is particularly preferable.

The rotating brush roll that can be preferably used in the present invention can be appropriately selected in consideration of the difficulty of scratching the image area and the stiffness of the lithographic printing plate precursor support.
As the rotating brush roll, a known one formed by planting a brush material on a plastic or metal roll can be used. For example, a metal or plastic in which brush materials are implanted in a row, as described in JP-A-58-159533, JP-A-3-100554, or JP-A-62-167253 A brush roll in which the groove mold material is radially wound around a plastic or metal roll as a core without any gap can be used.
Examples of brush materials include plastic fibers (for example, polyesters such as polyethylene terephthalate and polybutylene terephthalate, polyamides such as nylon 6.6 and nylon 6.10, polyacrylics such as polyacrylonitrile and poly (meth) acrylate). , And polyolefin-based synthetic fibers such as polypropylene and polystyrene). For example, fiber diameters of 20 to 400 μm and hair lengths of 5 to 30 mm can be suitably used. .
The outer diameter of the rotating brush roll is preferably 30 to 200 mm, and the peripheral speed at the tip of the brush rubbing the plate surface is preferably 0.1 to 5 m / sec.

  The rotating direction of the rotating brush roll may be the same or opposite to the conveying direction of the lithographic printing plate precursor. However, when two or more rotating brush rolls are used, at least one rotating brush roll is used. Preferably, the rotating brush rolls rotate in the same direction, and at least one rotating brush roll rotates in the opposite direction. This further ensures the removal of the unexposed photosensitive layer. It is also effective to swing the rotating brush roll in the direction of the rotation axis of the brush roll.

  The developer used in the present invention may always be a fresh solution, but it is preferable to circulate the developer after the development treatment through a filter and repeatedly use it.

Any filter can be used for filtering the developer used in the developing step as long as it can filter foreign matter mixed in the developer. As a material for the filter, polyester resin, polypropylene resin, polyethylene resin, cellulose resin, cotton, or the like is preferably used. In addition, as a form of the filter, a filter that is housed in a cartridge in a housing as a replaceable filter is preferable. The cartridge is made of, for example, a filter paper made of cellulose fiber, processed with an epoxy resin for reinforcing the strength and preventing the fiber from coming off, and a pleat type molded into a pleat shape to increase the filtration area. Bundle) is stored in a depth type rolled up to obtain a gentler density gradient than the center tube, or a plastic case such as polyethylene is used to store the adsorbent, or is mainly composed of resin, cellulose, glass fiber and water-absorbing polymer An adsorption type in which an adsorbent such as activated carbon is supported on the prepared media is preferable. The adsorbent was selected from silica gel, activated carbon, activated aluminum, molecular sieve, clay and superabsorbent fiber, calcium carbonate, calcium sulfate, potassium permanganate, sodium carbonate, potassium carbonate, sodium phosphate and active metal. Materials and ion exchangers used for various filters can be used.
As an available filter, cartridge filters “TCW type”, “TCP type”, “TCS type” manufactured by Advantech Toyo Co., Ltd. are preferably used.
The mesh diameter of the filter is preferably 5 to 500 μm, more preferably 10 to 200 μm, and still more preferably 20 to 100 μm.

In the lithographic printing plate making method of the present invention, it is preferable to carry out the development step continuously twice or more. As a specific method for continuously performing such development processing twice or more, the development processing is performed twice using an automatic processor (see FIG. 2) including only the developing section having the rubbing member as described above. A method of repeating the above (in that case, two or more automatic processors may be connected), a method of using an automatic processor having a plurality of developing units equipped with a rubbing member as described above, and the like. It is done.
Moreover, as a preferable form of the plate making method of the lithographic printing plate of the present invention, a water washing step is performed following the development step. By performing the above-described continuous development and water washing steps, printing stains due to re-deposition of the development removal component on the plate surface are suppressed.
The water used in the washing step can be any water such as general tap water, well water, ion exchange water, or distilled water, but tap water and well water are preferable from an economical viewpoint. It is preferable that the water used in the washing step is always fresh water, or the water used in the washing step is circulated through the filter as described above and reused.

Subsequent to the washing step, it is possible to further perform a desensitization step of the non-image area with a gum solution after the developing step. By supplying the gum solution to the printing plate after the water washing step, the non-image area can be sufficiently desensitized.
In the desensitization step, a general gum solution or a developer containing a water-soluble polymer compound (also referred to as “water-soluble resin”) among the developers is used. In the latter case, it is preferable in view of the apparatus structure to use a solution having basically the same composition as the developer used in the development step. This means that the developer charged in the tank of the developing unit and the liquid charged in the tank of the desensitizing unit are the same, and the developer component taken out by the subsequent development process or the lithographic printing plate precursor component It does not mean compositional change due to contamination, water evaporation or carbon dioxide dissolution. As a result, it is possible to make common the charge liquid and replenisher used in each process. Furthermore, as a replenisher for the developing unit, a cascade method may be employed in which the necessary amount is supplied by overflowing the circulating liquid in the desensitizing unit.

The gum solution used in the desensitizing step after the water washing step will be described.
The desensitizing agent used in the gum solution is preferably gum arabic, and more preferably 15 to 20% by weight aqueous solution of gum arabic.
In addition to gum arabic, various water-soluble resins are used as a desensitizing agent. For example, water-soluble polysaccharides extracted from dextrin, steravic, structan, alginates, polyacrylates, hydroxyethylcellulose, polyvinylpyrrolidone, polyacrylamide, methylcellulose, hydroxypropylcellulose, hydroxymethylcellulose, carboxyalkylcellulose salts, soybean okara In addition, pullulan or pullulan derivatives and polyvinyl alcohol are also preferable.

  Further, as a desensitizing agent, modified starch derivatives such as roasted starch such as British gum, enzyme modified dextrins such as enzyme dextrin and shardinger dextrin, oxidized starch shown in solubilized starch, modified pregelatinized starch and unmodified alpha Pregelatinized starch such as modified starch, phosphate starch, fat starch, sulfate starch, nitrate starch, xanthate starch and carbamate starch, carboxyalkyl starch, hydroxyalkyl starch, sulfoalkyl starch, cyanoethyl starch, allyl Starch, benzyl starch, carbamylethyl starch, etherified starch such as dialkylamino starch, methylol crosslinked starch, hydroxyalkyl crosslinked starch, phosphate crosslinked starch, crosslinked starch such as dicarboxylic acid crosslinked starch, starch polyacrylamide copolymer, starch Polyacry Acid copolymer, starch polyvinyl acetate copolymer, starch polyacrylonitrile copolymer, chaotic starch polyacrylic ester copolymer, chaotic starch vinyl polymer copolymer, starch polystyrene maleic acid copolymer, starch polyethylene Starch graft polymers such as oxide copolymers and starch polypropylene copolymers are preferred.

  Natural polymer compounds that can be used as a desensitizing agent include starch such as candied starch, potato starch, tapioca starch, wheat starch and corn starch, carrageenan, laminaran, seaweed mannan, funori, Irish moss, agar Obtained from algae such as sodium alginate, troolloi, mannan, quince seed, pectin, tragacanth gum, karaya gum, xanthine gum, guarbin gum, locust bin gum, carob gum, benzoin gum, etc., dextran, glucan, levan, etc. Homopolysaccharides and microbial mucilages such as hetropolysaccharides such as succinoglucan and santham gum, and proteins such as glue, gelatin, casein and collagen are preferred.

  Two or more water-soluble resins can be used in combination, and can be contained in the gum solution in an amount of preferably 1 to 50% by weight, more preferably 3 to 30% by weight.

The gum solution may contain a pH adjuster, surfactant, preservative, antifungal agent, lipophilic substance, wetting agent, chelating agent, antifoaming agent and the like in addition to the above desensitizing agent.
The gum solution is preferably used in the range of pH 3 to 12, and therefore a pH adjuster is preferably added. In order to adjust the pH to 3 to 12, it is preferable to add and adjust a mineral acid, an organic acid, an inorganic salt, or the like in the gum solution. The addition amount is preferably 0.01 to 2% by weight.
For example, as the mineral acid, nitric acid, sulfuric acid, phosphoric acid, metaphosphoric acid and the like can be mentioned.
Examples of the organic acid include acetic acid, succinic acid, malonic acid, p-toluenesulfonic acid, levulinic acid, phytic acid, organic phosphonic acid, polystyrene sulfonic acid, and amino acids such as glycine, α-alanine, and β-alanine. .
Examples of the inorganic salt include magnesium nitrate, primary sodium phosphate, secondary sodium phosphate, nickel sulfate, sodium hexametaphosphate, sodium tripolyphosphate, and the like. You may use together 2 or more types, such as a mineral acid, an organic acid, or an inorganic salt.

Examples of the surfactant contained in the gum solution include an anionic surfactant, a cationic surfactant, an amphoteric surfactant, and a nonionic surfactant.
Anionic surfactants include fatty acid salts, abietic acid salts, hydroxyalkane sulfonates, alkane sulfonates, α-olefin sulfonates, dialkyl sulfosuccinates, alkyl diphenyl ether disulfonates, linear alkyl benzene sulfonates, branched Chain alkylbenzene sulfonates, alkylnaphthalene sulfonates, alkylphenoxy polyoxyethylene propyl sulfonates, polyoxyethylene alkyl sulfophenyl ether salts, sodium N-methyl-N-oleyl taurate, disodium N-alkylsulfosuccinate monoamide Salts, petroleum sulfonates, sulfated castor oil, sulfated beef tallow oil, fatty acid alkyl ester sulfate esters, alkyl sulfate esters, polyoxy Ethylene alkyl ether sulfates, fatty acid monoglyceride sulfates, polyoxyethylene alkylphenyl ether sulfates, polyoxyethylene styryl phenyl ether sulfates, alkyl phosphates, polyoxyethylene alkyl ether phosphates, polyoxyethylene Examples thereof include alkyl phenyl ether phosphate esters, saponification products of styrene-maleic anhydride copolymers, partial saponification products of olefin-maleic anhydride copolymers, and naphthalene sulfonate formalin condensates.
Among these, dialkyl sulfosuccinates, alkyl sulfate esters, alkyl naphthalene sulfonates, α-olefin sulfonates, and alkyl diphenyl ether disulfonates are particularly preferably used.

Preferred examples of the cationic surfactant include alkylamine salts and quaternary ammonium salts.
Preferred examples of the amphoteric surfactant include alkyl carboxybetaines, alkyl imidazolines, alkylaminocarboxylic acids and the like.
Nonionic surfactants include polyoxyethylene alkyl ethers, polyoxyethylene alkyl phenyl ethers, polyoxyethylene polystyryl phenyl ether, polyoxyethylene polyoxypropylene alkyl ether, 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 oil, polyoxyethylene glycerin fatty acid partial esters, fatty acid diethanol Mido, N, N-bis-2-hydroxyalkylamines, polyoxyethylene alkylamine, triethanolamine fatty acid ester, trialkylamine oxide, polypropylene glycol molecular weight 200-5,000, trimethylolpropane, glycerin or sorbitol Preferable examples include adducts of polyoxyethylene or polyoxypropylene, acetylene glycols, and the like. Fluorine-based and silicone-based nonionic surfactants can also be used in the same manner.

  Two or more surfactants can be used in combination. The amount used is not particularly limited, but is preferably 0.01 to 20% by weight, more preferably 0.05 to 10% by weight, based on the total weight of the gum solution.

As the preservative, known preservatives used in the fields of fiber, wood processing, food, medicine, cosmetics, agricultural chemicals and the like can be used. For example, quaternary ammonium salts, monohydric phenol derivatives, dihydric phenol derivatives, polyhydric phenol derivatives, imidazole derivatives, pyrazolopyrimidine derivatives, monovalent naphthols, carbonates, sulfone derivatives, organotin compounds, cyclopentane derivatives, phenyl derivatives , Phenol ether derivatives, phenol ester derivatives, hydroxylamine derivatives, nitrile derivatives, naphthalenes, pyrrole derivatives, quinoline derivatives, benzothiazole derivatives, secondary amines, 1,3,5-triazine derivatives, thiadiazole derivatives, anilide derivatives, pyrrole Derivatives, halogen derivatives, dihydric alcohol derivatives, dithiols, cyanic acid derivatives, thiocarbamic acid derivatives, diamine derivatives, isothiazole derivatives, monohydric alcohols, saturated aldehydes, Saturated monocarboxylic acid, saturated ether, unsaturated ether, lactone, amino acid derivative, hydantoin, cyanuric acid derivative, guanidine derivative, pyridine derivative, saturated monocarboxylic acid, benzenecarboxylic acid derivative, hydroxycarboxylic acid derivative, biphenyl, hydroxamic acid derivative , Aromatic alcohols, halogenophenol derivatives, benzenecarboxylic acid derivatives, mercaptocarboxylic acid derivatives, quaternary ammonium salt derivatives, triphenylmethane derivatives, hinokitiol, furan derivatives, benzofuran derivatives, acridine derivatives, isoquinoline derivatives, arsine derivatives, thiocarbamine Acid derivatives, phosphate esters, halogenobenzene derivatives, quinone derivatives, benzenesulfonic acid derivatives, monoamine derivatives, organophosphate esters, piperazine derivatives Body, phenazine derivatives, pyrimidine derivatives, thiophanate derivatives, imidazoline derivatives, isoxazole derivatives, known preservatives such as ammonium salt derivatives can be used.
Particularly preferred preservatives include pyridinethiol-1-oxide salts, salicylic acid and its salts, 1,3,5-trishydroxyethylhexahydro-S-triazine, 1,3,5-trishydroxymethylhexahydro-S- Examples include triazine, 1,2-benzisothiazolin-3-one, 5-chloro-2-methyl-4-isothiazolin-3-one, and 2-bromo-2-nitro-1,3-propanediol.
Moreover, it is preferable to use 2 or more types of preservatives together so that it may be effective with respect to various molds and bacteria.
The preferred content is an amount that exerts a stable effect on bacteria, molds, yeasts, etc., and varies depending on the types of bacteria, molds, yeasts, but 0.01% based on the total weight of the gum solution. A range of ˜4% by weight is preferred.

The gum solution can also contain a lipophilic substance.
Preferable examples of the lipophilic substance include organic carboxylic acids having 5 to 25 carbon atoms such as oleic acid, lanolinic acid, valeric acid, nonylic acid, capric acid, myristic acid, palmitic acid, and castor oil.
A lipophilic substance can be used individually by 1 type or in combination of 2 or more types.
The content of the lipophilic substance in the gum solution is preferably 0.005 to 10% by weight and more preferably 0.05 to 5% by weight with respect to the total weight of the gum solution.

In addition, as a wetting agent for gum solution, glycerin, ethylene glycol, propylene glycol, triethylene glycol, butylene glycol, hexylene glycol, diethylene glycol, dipropylene glycol, glycerin, trimethylolpropane, diglycerin, polyoxyethylene, etc. Can be added.
Wetting agents may be used alone or in combination of two or more.
A preferable amount of the wetting agent is 0.1 to 5% by weight based on the total weight of the gum solution.

A chelating agent may be added to the gum solution.
The gum solution is usually marketed as a concentrated solution, and is used after being diluted by adding tap water, well water or the like at the time of use. The calcium ions contained in the diluted tap water and well water may adversely affect printing and may cause the printed matter to be easily soiled. Therefore, the above disadvantages can be solved by adding a chelating agent. . Preferred chelating agents include, for example, ethylenediaminetetraacetic acid, its potassium salt, its sodium salt; diethylenetriaminepentaacetic acid, its potassium salt, its sodium salt; triethylenetetraminehexaacetic acid, its potassium salt, its sodium salt, hydroxyethylethylenediaminetrimethyl Acetic acid, potassium salt, sodium salt; nitrilotriacetic acid, sodium salt; 1-hydroxyethane-1,1-diphosphonic acid, potassium salt, sodium salt; aminotri (methylenephosphonic acid), potassium salt, sodium Mention may be made of organic phosphonic acids such as salts or phosphonoalkanetricarboxylic acids. Organic amine salts are also effective in place of the sodium and potassium salts of the chelating agents.
As the chelating agent, a chelating agent that is stably present in the gum solution composition and does not inhibit the printability is selected. The content is preferably 0.001 to 1.0% by weight with respect to the total weight of the gum solution.

  The gum solution may contain an antifoaming agent, and a silicone antifoaming agent is particularly preferable. Moreover, any of an emulsified dispersion type and a solubilized type can be used. The preferable content of the antifoaming agent is in the range of 0.001 to 1.0% by weight with respect to the total weight of the gum solution.

The gum solution may be prepared as an emulsified dispersion type, an organic solvent is used as its oil phase, and it is made into a solubilized type (emulsified type) with the aid of a surfactant as described above. Good.
The organic solvent is preferably an organic solvent having a solubility in water of 5% by weight or less at 20 ° C. and a boiling point of 160 ° C. or higher. For example, phthalic acid diester agents such as dibutyl phthalate, diheptyl phthalate, di-n-octyl phthalate, di (2-ethylhexyl) phthalate, dinonyl phthalate, didecyl phthalate, dilauryl phthalate, butyl benzyl phthalate, etc. Aliphatic dibasic acid esters such as butyl glycol adipate, dioctyl azelate, dibutyl sebacate, di (2-ethylhexyl) sebacate, dioctyl sebacate, for example, epoxidized triglycerides such as epoxidized soybean oil, The freezing point of phosphoric acid esters such as cresyl phosphate, trioctyl phosphate, trischlorl phosphate, and benzoic acid esters such as benzyl benzoate is 15 ° C. or lower. Boiling point at one atmosphere include 300 ° C. or more plasticizers.

  Other alcohol solvents include 2-octanol, 2-ethylhexanol, nonanol, n-decanol, undecanol, n-dodecanol, trimethylnonyl alcohol, tetradecanol, benzyl alcohol and the like. Examples of the glycol solvent include ethylene glycol monophenyl ether, ethylene glycol benzyl ether, butyl cellosolve, octylene glycol and the like.

  Odor is particularly mentioned as a condition when selecting the compound. The amount of these solvents used is preferably 0.1 to 5% by weight of the desensitizing agent, and more preferably 0.5 to 3% by weight. A solvent may be used individually by 1 type, or may use 2 or more types together.

  In addition to the above-mentioned gum solutions, gum solutions described in EP 1342568, EP 1788444 and the like can also be suitably used.

  The gum solution is prepared by preparing a water phase at a temperature of 40 ° C. ± 5 ° C., stirring at high speed, slowly dropping the prepared oil phase into the water phase, stirring sufficiently, and then emulsifying and dispersing through a pressure type homogenizer. It is preferable.

  The remaining component of the gum solution is water. It is advantageous for transportation that the gum solution is a concentrated solution with a reduced water content and is diluted with water at the time of use. In this case, the degree of concentration is appropriate such that each component does not cause separation or precipitation.

  Although the temperature of the developing solution in the developing step, the water in the washing step, and the gum solution in the desensitizing step can be used separately at any temperature, it is preferably in the range of 10 ° C to 50 ° C.

In the present invention, a drying step can be optionally provided after each step. In particular, it is preferably provided in the last step of the automatic processor, and more preferably provided between the water washing step and the desensitizing step.
The drying step is preferably performed by blowing dry air at an arbitrary temperature after most of the developer is removed by a roller nip.

(Exposure process)
The plate-making method of the lithographic printing plate of the present invention includes a step of exposing the negative lithographic printing plate precursor imagewise (exposure step).
Prior to the development step, the exposure step is performed. In the exposure step, the negative lithographic printing plate precursor obtained in the original plate preparation step is exposed through a transparent original image having a line image, a halftone dot image or the like, or imagewise exposed by laser light scanning or the like using digital data. It is preferable.
The “image” in the present invention is a concept including characters, numbers, symbols, and the like in addition to narrowly defined images such as figures and pictorial photographs, and includes a mixture of them.
Examples of light sources suitable for exposure include carbon arc lamps, mercury lamps, xenon lamps, metal hydrado lamps, strobes, LEDs, and laser beams. A laser beam is particularly preferable, and examples include solid lasers and semiconductor lasers that emit infrared light of 760 to 1,200 nm, ultraviolet semiconductor lasers that emit light of 250 to 420 nm, argon ion lasers that emit visible light, and FD-YAG lasers. . Among these, from the viewpoint of simplification of plate making, a laser that emits infrared rays that can be operated under white light or yellow light is preferable.
Regarding the infrared laser, the output is preferably 100 mW or more, the exposure time per pixel is preferably within 20 μs, and the irradiation energy amount is preferably 10 to 300 mJ / cm ² . In order to shorten the exposure time, it is preferable to use a multi-beam laser device.

(Original plate production process)
The plate-making method of the lithographic printing plate of the present invention includes a step of preparing a negative lithographic printing plate precursor having a photopolymerizable photosensitive layer (also simply referred to as “photosensitive layer”) on the support (original plate preparation step).
The constituent elements and components of the lithographic printing plate precursor that can be used in the present invention are described below.

<Lithographic printing plate precursor>
The lithographic printing plate precursor used in the present invention is a negative type image forming in which an image-exposed region is cured to become an image portion, and an unexposed portion is removed by the development processing as described above to form a non-image portion. It has the function. In the present invention, “having a photosensitive layer on a support” means that even if the photosensitive layer is provided in direct contact with the support, another layer is provided between the support and the photosensitive layer. The presence of an optional layer such as a protective layer, an undercoat layer, an intermediate layer, and a backcoat layer provided as desired in the lithographic printing plate precursor is not denied.

(Photosensitive layer)
A typical image forming mechanism of the photosensitive layer of the lithographic printing plate precursor used in the present invention contains (Component a) a sensitizing dye, (Component b) a polymerization initiator and (Component c) a polymerizable compound, and is exposed. An embodiment in which the region is polymerized and cured to form an image portion is preferred. That is, the photosensitive layer preferably contains (Component a) a sensitizing dye, (Component b) a polymerization initiator, and (Component c) a polymerizable compound.
The photosensitive layer is preferably an infrared light sensitive photosensitive layer.
Further, the photosensitive layer is sensitive to infrared light, and more preferably contains a triphenylalkyl borate salt or a tetraphenylborate salt, and further preferably contains a copper phthalocyanine pigment.
Further, it is more preferable that the photosensitive layer is sensitive to infrared light, does not contain a borate salt, and contains a colored dye.
These infrared light-sensitive photosensitive layers particularly preferably contain a cyanine dye and an iodonium salt.
Below, each component contained in a photosensitive layer is demonstrated sequentially.

(Component a) Sensitizing dye The photosensitive layer preferably contains (Component a) a sensitizing dye.
For example, a sensitizing dye having a maximum absorption at 350 to 450 nm, a sensitizing dye having a maximum absorption at 500 to 600 nm, and an infrared absorber having a maximum absorption at 750 to 1,400 nm are added to the photosensitive layer. High-sensitivity lithographic printing plate precursors corresponding to a 405 nm violet laser, a 532 nm green laser, and a 803 nm IR laser, which are usually used in the industry, can be provided.
First, a sensitizing dye having a maximum absorption in the wavelength region of 350 to 450 nm will be described. Examples of such sensitizing dyes include merocyanine dyes, benzopyrans, coumarins, aromatic ketones, anthracenes and the like.

  Among the sensitizing dyes having an absorption maximum in the wavelength range of 350 to 450 nm, a dye preferable from the viewpoint of high sensitivity is a dye represented by the following formula (IV).

In the formula (IV), A represents an aromatic ring group or a heterocyclic group which may have a substituent, and X represents an oxygen atom, a sulfur atom or N- (R ₃ ). R ₁ , R ₂ and R ₃ each independently represent a monovalent nonmetallic atomic group, and A and R ₁ and R ₂ and R ₃ are bonded to each other to form an aliphatic or aromatic ring. You may form.

Formula (IV) will be described in more detail. R ₁ , R ₂ and R ₃ are each independently a monovalent nonmetallic atomic group, preferably a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted aryl group, It represents a substituted or unsubstituted aromatic heterocyclic residue, a substituted or unsubstituted alkoxy group, a substituted or unsubstituted alkylthio group, a hydroxyl group, or a halogen atom.

A in Formula (IV) represents an aromatic ring group or a heterocyclic group which may have a substituent, and the aromatic ring or heterocyclic ring which may have a substituent is R in Formula (IV) Examples thereof include the same as the substituted or unsubstituted aryl group and the substituted or unsubstituted aromatic heterocyclic residue described in ₁ , R ₂ and R ₃ .

  Specific examples of such a sensitizing dye include compounds described in paragraphs 0047 to 0053 of JP-A-2007-58170.

  Furthermore, sensitizing dyes represented by the following formulas (V) to (VII) can also be used.

In formula (V), R ^{1 to} R ¹⁴ each independently represents a hydrogen atom, an alkyl group, an alkoxy group, a cyano group or a halogen atom. However, at least one of R ^{1 to} R ¹⁰ represents an alkoxy group having 2 or more carbon atoms.
In the formula (VI), R ^{15 to} R ³² each independently represents a hydrogen atom, an alkyl group, an alkoxy group, a cyano group, or a halogen atom. However, at least one of R ^{15 to} R ²⁴ represents an alkoxy group having 2 or more carbon atoms.

In formula (VII), R ¹ , R ² and R ³ each independently represent a halogen atom, an alkyl group, an aryl group, an aralkyl group, an —NR ⁴ R ⁵ group or an —OR ⁶ group, and R ⁴ , R ⁵ And R ⁶ each independently represents a hydrogen atom, an alkyl group, an aryl group or an aralkyl group, and k, m and n each independently represents an integer of 0 to 5.

JP2007-171406, JP2007-206216, JP2007-206217, JP2007-225701, JP2007-225702, JP2007-316582, and JP2007-. A sensitizing dye described in each publication of No. 328243 can also be preferably used.
The preferred addition amount of a sensitizing dye having an absorption maximum in the wavelength range of 350 to 450 nm is preferably 0.05 to 30 parts by weight, more preferably 0.1 to 20 parts per 100 parts by weight of the total solid content of the photosensitive layer. Part by weight, most preferably in the range of 0.2 to 10 parts by weight.

Subsequently, a sensitizing dye having a maximum absorption in a wavelength range of 750 to 1,400 nm that is preferably used in the present invention will be described in detail.
Such a sensitizing dye includes an infrared absorber, and is highly sensitive to infrared laser irradiation (exposure) and is in an electronically excited state. Electron transfer, energy transfer, and heat generation (photothermal conversion function) related to the electronically excited state. It is estimated that these act on the polymerization initiator coexisting in the photosensitive layer to cause a chemical change in the polymerization initiator to generate radicals. In any case, the addition of a sensitizing dye having a maximum absorption at 750 to 1,400 nm is particularly suitable for plate making directly drawn with an infrared laser beam having a wavelength of 750 to 1,400 nm. Compared with the printing plate precursor, it can exhibit high image forming properties.

  The infrared absorber is preferably a dye or pigment having an absorption maximum in a wavelength range of 750 to 1,400 nm.

As the dye, commercially available dyes and known dyes described in documents such as “Dye Handbook” (edited by the Society for Synthetic Organic Chemistry, published in 1970) can be used.
Specifically, dyes such as azo dyes, metal complex azo dyes, pyrazolone azo dyes, naphthoquinone dyes, anthraquinone dyes, phthalocyanine dyes, carbonium dyes, quinoneimine dyes, methine dyes, cyanine dyes, squarylium dyes, pyrylium salts, metal thiolate complexes, etc. Is mentioned.
Particularly preferred among these dyes are cyanine dyes, squarylium dyes, pyrylium salts, nickel thiolate complexes, and indolenine cyanine dyes. Further, cyanine dyes and indolenine cyanine dyes are preferred, and particularly preferred examples include cyanine dyes represented by the following formula (a).

In the formula (a), X ¹ represents a hydrogen atom, a halogen atom, -NPh ₂ , X ² -L ¹ or a group shown below. Here, Ph represents a phenyl group, X ² represents an oxygen atom, a nitrogen atom or a sulfur atom, L ¹ represents a hydrocarbon group having 1 to 12 carbon atoms, an aromatic ring having a hetero atom, or a hetero atom. A hydrocarbon group having 1 to 12 carbon atoms is included. Here, the hetero atom represents N, S, O, a halogen atom, or Se. X _a ^- is Z _a which will be described below ^- has the same definition as, R ^a represents a hydrogen atom, an alkyl group, an aryl group, a substituent selected from the group consisting of substituted or unsubstituted amino groups and halogen atoms.

R ¹ and R ² each independently represents a hydrocarbon group having 1 to 12 carbon atoms. In view of storage stability of the photosensitive layer coating solution, R ¹ and R ² are preferably independently a hydrocarbon group having 2 or more carbon atoms, and R ¹ and R ² are bonded to each other. It is particularly preferable that a member ring or a six member ring is formed.

Ar ¹ and Ar ² may be the same or different and each represents an aromatic hydrocarbon group which may have a substituent.
Preferred aromatic hydrocarbon groups include a benzene ring and a naphthalene ring. Moreover, as a preferable substituent, a C12 or less hydrocarbon group, a halogen atom, and a C12 or less alkoxy group are mentioned.
Y ¹ and Y ² may be the same or different and each represents a sulfur atom or a dialkylmethylene group having 12 or less carbon atoms.
R ³ and R ⁴ may be the same or different and each represents a hydrocarbon group having 20 or less carbon atoms which may have a substituent. Preferred substituents include alkoxy groups having 12 or less carbon atoms, carboxyl groups, and sulfo groups.
R ⁵ , R ⁶ , R ⁷ and R ⁸ may be the same or different and each represents a hydrogen atom or a hydrocarbon group having 12 or less carbon atoms. From the availability of raw materials, a hydrogen atom is preferred.
Further, Z _a ^- represents a counter anion. However, when the cyanine dye represented by formula (a) has an anionic substituent in the structure thereof, Z _a is does not require charge neutralization ^- is not necessary. Z _a ^- is preferably a halide ion, a perchlorate ion, a tetrafluoroborate ion, a hexafluorophosphate ion, or a sulfonate ion in view of the storage stability of the photosensitive layer coating solution. An ion or an allyl sulfonate ion is particularly preferable. From the viewpoint of increasing sensitivity, triphenylalkylborate ions and tetraphenylborate ions are also preferably used. It is particularly preferable that the counter ion does not contain a halide ion.

In the present invention, it is preferable to use a water-soluble cyanine dye as the sensitizing dye.
Examples of the water-soluble cyanine dye include those described in JP-A No. 2004-351823, and a sulfonic acid group and / or a salt thereof, a phosphonic acid group and / or a salt thereof as a hydrophilic group in the molecule. It preferably has at least one selected from a carboxylic acid group and / or a salt thereof, and a hydroxyl group.
Among these, it is more preferable that the molecule has two or more sulfonic acid groups and / or salts thereof, phosphonic acid groups and / or salts thereof, and the counter ion is an inorganic ion.

  Although the specific example of the water-soluble cyanine dye suitable for this invention is shown below, it is not limited to these. In the following specific examples, Me represents a methyl group, and Et represents an ethyl group.

  Examples of pigments include commercially available pigments, Color Index (CI) Handbook, “Latest Pigment Handbook” (edited by the Japan Pigment Technology Association, published in 1977), “Latest Pigment Applied Technology” (published by CMC, published in 1986), The pigments described in “Printing Ink Technology” published by CMC (published in 1984) can be used.

  Examples of the pigment 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. Specifically, insoluble azo pigments, azo lake pigments, condensed azo pigments, chelate azo pigments, phthalocyanine pigments, anthraquinone pigments, perylene and perinone pigments, thioindigo pigments, quinacridone pigments, dioxazine pigments, isoindolinone pigments In addition, quinophthalone pigments, dyed lake pigments, azine pigments, nitroso pigments, nitro pigments, natural pigments, fluorescent pigments, inorganic pigments, carbon black, and the like can be used. Of these pigments, carbon black is preferred.

  These pigments may be used without surface treatment, or may be used after surface treatment. The surface treatment method includes a method of surface coating with a resin or wax, a method of attaching a surfactant, a method of bonding a reactive substance (eg, silane coupling agent, epoxy compound, polyisocyanate, etc.) to the pigment surface, etc. Can be considered. The above-mentioned surface treatment methods are described in “Characteristics and Applications of Metal Soap” (Shobobo), “Printing Ink Technology” (CMC Publishing, 1984) and “Latest Pigment Application Technology” (CMC Publishing, 1986). Yes.

  The particle size of the pigment is preferably in the range of 0.01 μm to 10 μm, more preferably in the range of 0.05 μm to 1 μm, and particularly preferably in the range of 0.1 μm to 1 μm. Within the above range, excellent dispersion stability of the pigment in the photosensitive layer can be obtained, and a uniform photosensitive layer can be obtained.

  As a method for dispersing the pigment, a known dispersion technique used in ink production, toner production, or the like can be used. 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 disperser, a KD mill, a colloid mill, a dynatron, a three-roll mill, and a pressure kneader. Details are described in "Latest Pigment Applied Technology" (CMC Publishing, 1986).

  The sensitizing dye may be added to the same layer as other components, or another layer may be provided and added thereto.

  From the viewpoint of uniformity in the photosensitive layer and durability of the photosensitive layer, the content of the sensitizing dye is preferably 0.01 to 50% by weight based on the total solid content constituting the photosensitive layer. It is more preferably 1 to 10% by weight, particularly preferably 0.5 to 10% by weight in the case of dyes, and particularly preferably 0.1 to 10% by weight in the case of pigments.

(Component b) Polymerization initiator The photosensitive layer preferably contains a polymerization initiator (hereinafter also referred to as “initiator compound”).
The initiator compound is a compound that undergoes a chemical change through the action of electron transfer, energy transfer, heat generation, etc. caused by the electronic excitation state of the sensitizing dye, and generates at least one selected from radicals, acids, and bases. is there. Hereinafter, radicals, acids, and bases generated in this way are simply referred to as active species. A practically sufficient sensitivity can be obtained by using the initiator compound. As one embodiment in which the sensitizing dye and the initiator compound are used in combination, these may be used as a single compound by an appropriate chemical method (such as linking by a chemical bond between the sensitizing dye and the initiator compound). Is possible.

  Usually, many of these initiator compounds are considered to generate active species through any of the following initial chemical processes represented by (1) to (3). (1) Reductive decomposition of the initiator compound based on the electron transfer reaction from the electronically excited state of the sensitizing dye to the initiator compound, (2) Electron transfer from the initiator compound to the electronically excited state of the sensitizing dye (3) decomposition of the initiator compound from the electronically excited state based on energy transfer from the electronically excited state of the sensitizing dye to the initiator compound. It is often ambiguous as to which type (1) to (3) each individual initiator compound belongs, but in the present invention, a very high increase can be achieved even when combined with any of these types of initiator compounds. A feeling effect is obtained.

  As the initiator compound in the present invention, those known among those skilled in the art can be used without limitation. Specifically, for example, trihalomethyl compounds, carbonyl compounds, organic peroxides, azo compounds, azide compounds, metallocene compounds can be used. , Hexaarylbiimidazole compounds, organic boron compounds, disulfone compounds, oxime ester compounds, onium salt compounds, and iron arene complexes. Among these, at least one selected from the group consisting of hexaarylbiimidazole compounds, onium salts, trihalomethyl compounds, and metallocene compounds is preferable, and hexaarylbiimidazole compounds are particularly preferable. Two or more polymerization initiators may be used in combination as appropriate.

Examples of hexaarylbiimidazole compounds include lophine dimers described in JP-B-45-37377 and JP-B-44-86516, for example, 2,2′-bis (o-chlorophenyl) -4,4 ′, 5. , 5′-tetraphenylbiimidazole, 2,2′-bis (o-bromophenyl) -4,4 ′, 5,5′-tetraphenylbiimidazole, 2,2′-bis (o, p-dichlorophenyl) -4,4 ', 5,5'-tetraphenylbiimidazole, 2,2'-bis (o-chlorophenyl) -4,4', 5,5'-tetra (m-methoxyphenyl) biimidazole, 2, 2′-bis (o, o′-dichlorophenyl) -4,4 ′, 5,5′-tetraphenylbiimidazole, 2,2′-bis (o-nitrophenyl) -4,4 ′, 5,5 ′ -Tetraphenylbiimidazole 2,2′-bis (o-methylphenyl) -4,4 ′, 5,5′-tetraphenylbiimidazole, 2,2′-bis (o-trifluoromethylphenyl) -4,4 ′, Examples include 5,5′-tetraphenylbiimidazole.
The hexaarylbiimidazole compound is particularly preferably used in combination with a sensitizing dye having a maximum absorption at 350 to 450 nm.

  The onium salt suitably used in the present invention (in the present invention, functions as an ionic polymerization initiator, not as an acid generator) is represented by the following formulas (RI-I) to (RI-III). Onium salt.

In the formula (RI-I), Ar ₁₁ represents an aryl group having 20 or less carbon atoms which may have 1 to 6 substituents, and preferred substituents include an alkyl group having 1 to 12 carbon atoms and a carbon number. C2-C12 alkenyl group, C2-C12 alkynyl group, C6-C12 aryl group, C1-C12 alkoxy group, C6-C12 aryloxy group, halogen atom, C1-C1 12 alkylamino groups, C2-C12 dialkylamino groups, C1-C12 alkylamide groups or arylamide groups, carbonyl groups, carboxyl groups, cyano groups, sulfonyl groups, C1-C12 thioalkyl groups And a thioaryl group having 6 to 12 carbon atoms.
Z ₁₁ ^- represents a monovalent anion, specifically a halide ion, perchlorate ion, hexafluorophosphate ion, tetrafluoroborate ion, triphenyl alkyl borate ion, tetraphenyl borate ion, a sulfonate ion , Sulfinate ion, thiosulfonate ion, and sulfate ion. Among them, perchlorate ion, hexafluorophosphate ion, tetrafluoroborate ion, sulfonate ion, or sulfinate ion is preferable from the viewpoint of stability, and triphenylalkylborate ion, tetraphenylborate from the aspect of high sensitivity. Ions are preferred.

In formula (RI-II), Ar ₂₁ and Ar ₂₂ each independently represent an aryl group having 20 or less carbon atoms which may have 1 to 6 substituents, and preferred substituents include 1 to 1 carbon atoms. 12 alkyl groups, alkenyl groups having 2 to 12 carbon atoms, alkynyl groups having 2 to 12 carbon atoms, aryl groups having 6 to 12 carbon atoms, alkoxy groups having 1 to 12 carbon atoms, aryloxy groups having 6 to 12 carbon atoms, Halogen atom, C1-C12 alkylamino group, C2-C12 dialkylamino group, C1-C12 alkylamide group or arylamide group, carbonyl group, carboxyl group, cyano group, sulfonyl group, carbon Examples thereof include a thioalkyl group having 1 to 12 carbon atoms and a thioaryl group having 6 to 12 carbon atoms.
Z ₂₁ ^- represents a monovalent anion. Specific examples include halide ions, perchlorate ions, hexafluorophosphate ions, tetrafluoroborate ions, sulfonate ions, sulfinate ions, thiosulfonate ions, sulfate ions, and carboxylate ions. Among them, perchlorate ion, hexafluorophosphate ion, tetrafluoroborate ion, triphenylalkylborate ion, tetraphenylborate ion, sulfonate ion, sulfinate ion and carboxylate ion are preferable from the viewpoint of stability and reactivity. From the viewpoint of increasing sensitivity, triphenylalkylborate ions and tetraphenylborate ions are particularly preferable.

In the formula (RI-III), R ₃₁ , R ₃₂ and R ₃₃ are each independently an aryl group, an alkyl group, an alkenyl group having 20 or less carbon atoms, which may have 1 to 6 substituents, or Represents an alkynyl group. Among them, an aryl group is preferable from the viewpoint of reactivity and stability. Examples of the substituent include an alkyl group having 1 to 12 carbon atoms, an alkenyl group having 2 to 12 carbon atoms, an alkynyl group having 2 to 12 carbon atoms, an aryl group having 6 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, Aryloxy group having 6 to 12 carbon atoms, halogen atom, alkylamino group having 1 to 12 carbon atoms, dialkylamino group having 2 to 12 carbon atoms, alkylamide group or arylamide group having 1 to 12 carbon atoms, carbonyl group, carboxyl Group, a cyano group, a sulfonyl group, a thioalkyl group having 1 to 12 carbon atoms, and a thioaryl group having 6 to 12 carbon atoms.
Z ₃₁ ^- represents a monovalent anion. Specific examples include halide ions, perchlorate ions, hexafluorophosphate ions, tetrafluoroborate ions, sulfonate ions, sulfinate ions, thiosulfonate ions, sulfate ions, and carboxylate ions. Among them, in terms of stability and reactivity, perchlorate ion, hexafluorophosphate ion, tetrafluoroborate ion, triphenylalkylborate ion, tetraphenylborate ion, sulfonate ion, sulfinate ion, carboxylate ion are preferable. In particular, triphenylalkylborate ions and tetraphenylborate ions are preferable from the viewpoint of high sensitivity.
Moreover, the carboxylate ion of Unexamined-Japanese-Patent No. 2001-343742 and the carboxylate ion of Unexamined-Japanese-Patent No. 2002-148790 are preferably used.
The onium salt is particularly preferably used in combination with an infrared absorber having a maximum absorption at 750 to 1,400 nm.

  In addition, JP 2007-171406, JP 2007-206216, JP 2007-206217, JP 2007-225701, JP 2007-225702, JP 2007-316582, and JP 2007-328243. The polymerization initiators described in each of the above publications can be preferably used.

The polymerization initiator in the present invention is suitably used singly or in combination of two or more.
The amount of the polymerization initiator used in the photosensitive layer in the present invention is preferably 0.01 to 20% by weight, more preferably 0.1 to 15% by weight, based on the total solid content of the photosensitive layer. Preferably, the content is 1.0 to 10% by weight.

(Component c) Polymerizable compound The photosensitive layer preferably contains (Component c) a polymerizable compound.
The polymerizable compound (component c) that can be used in the present invention is an addition polymerizable compound having at least one ethylenically unsaturated bond, and preferably a compound having at least one terminal ethylenically unsaturated bond. More preferably, it is a compound having two or more. Such a compound group is widely known in the industrial field, and in the present invention, these can be used without any particular limitation. These have chemical forms such as monomers, prepolymers, that is, dimers, trimers and oligomers, copolymers thereof, and mixtures thereof.

  Examples of monomers include unsaturated carboxylic acids (for example, acrylic acid, methacrylic acid, itaconic acid, crotonic acid, isocrotonic acid, maleic acid, etc.), esters and amides thereof, preferably unsaturated carboxylic acids. An ester of an acid and an aliphatic polyhydric alcohol compound and an amide of an unsaturated carboxylic acid and an aliphatic polyamine compound are used. Further, an addition reaction product of an unsaturated carboxylic acid ester or amide having a nucleophilic substituent such as a hydroxy group, an amino group or a mercapto group with a monofunctional or polyfunctional isocyanate or epoxy, and a monofunctional or A dehydration condensation reaction product with a polyfunctional carboxylic acid is also preferably used. In addition, an addition reaction product of an isocyanate group, an unsaturated carboxylic acid ester or amide having an electrophilic substituent such as an epoxy group, and a monofunctional or polyfunctional alcohol, amine, or thiol, a halogeno group, Further, a substitution reaction product of an unsaturated carboxylic acid ester or amide having a leaving substituent such as a tosyloxy group and a monofunctional or polyfunctional alcohol, amine or thiol is also suitable. As another example, it is also possible to use a group of compounds substituted with unsaturated phosphonic acid, styrene, vinyl ether or the like instead of the unsaturated carboxylic acid.

  Specific examples of the monomer of an ester of an aliphatic polyhydric alcohol compound and an unsaturated carboxylic acid include acrylic acid esters such as ethylene glycol diacrylate, triethylene glycol diacrylate, 1,3-butanediol diacrylate, and tetramethylene glycol. Diacrylate, propylene glycol diacrylate, neopentyl glycol diacrylate, trimethylolpropane triacrylate, trimethylolpropane tri (acryloyloxypropyl) ether, trimethylolethane triacrylate, hexanediol diacrylate, 1,4-cyclohexanediol diacrylate , Tetraethylene glycol diacrylate, pentaerythritol diacrylate, pentaerythritol triacrylate , Pentaerythritol tetraacrylate, dipentaerythritol diacrylate, dipentaerythritol hexaacrylate, sorbitol triacrylate, sorbitol tetraacrylate, sorbitol pentaacrylate, sorbitol hexaacrylate, tri (acryloyloxyethyl) isocyanurate, polyester acrylate oligomer, etc. .

  Methacrylic acid esters include tetramethylene glycol dimethacrylate, triethylene glycol dimethacrylate, neopentyl glycol dimethacrylate, trimethylolpropane trimethacrylate, trimethylolethane trimethacrylate, ethylene glycol dimethacrylate, 1,3-butanediol dimethacrylate, Hexanediol dimethacrylate, pentaerythritol dimethacrylate, pentaerythritol trimethacrylate, pentaerythritol tetramethacrylate, dipentaerythritol dimethacrylate, dipentaerythritol hexamethacrylate, sorbitol trimethacrylate, sorbitol tetramethacrylate, bis [p- (3-methacryloxy- 2-hydroxypro ) Phenyl] dimethyl methane, bis - [p- (methacryloxyethoxy) phenyl] dimethyl methane, and the like.

Itaconic acid esters include ethylene glycol diitaconate, propylene glycol diitaconate, 1,3-butanediol diitaconate, 1,4-butanediol diitaconate, tetramethylene glycol diitaconate, pentaerythritol diitaconate Sorbitol tetritaconate and the like.
Examples of crotonic acid esters include ethylene glycol dicrotonate, tetramethylene glycol dicrotonate, pentaerythritol dicrotonate, and sorbitol tetradicrotonate.
Examples of isocrotonic acid esters include ethylene glycol diisocrotonate, pentaerythritol diisocrotonate, and sorbitol tetraisocrotonate.
Examples of maleic acid esters include ethylene glycol dimaleate, triethylene glycol dimaleate, pentaerythritol dimaleate, and sorbitol tetramaleate.

Examples of other esters include aliphatic alcohol esters described in JP-B-51-47334 and JP-A-57-196231, JP-A-59-5240, JP-A-59- Those having an aromatic skeleton described in JP-A No. 5241 and JP-A-2-226149 and those containing an amino group described in JP-A-1-165613 are also preferably used.
The aforementioned ester monomers can also be used as a mixture.

Specific examples of amide monomers of aliphatic polyvalent amine compounds and unsaturated carboxylic acids include methylene bisacrylamide, methylene bismethacrylamide, 1,6-hexamethylene bisacrylamide, 1,6-hexamethylene bismethacrylic. Examples include amide, diethylenetriamine trisacrylamide, xylylene bisacrylamide, and xylylene bismethacrylamide.
Examples of other preferable amide monomers include those having a cyclohexylene structure described in JP-B No. 54-21726.

Further, urethane-based addition-polymerizable compounds produced by using an addition reaction between an isocyanate and a hydroxy group are also suitable, and specific examples thereof are described in, for example, Japanese Patent Publication No. 48-41708. Vinyl urethane having two or more polymerizable vinyl groups in one molecule obtained by adding a vinyl monomer having a hydroxy group represented by the following formula (ii) to a polyisocyanate compound having two or more isocyanate groups in one molecule Compounds and the like.
^{_{CH 2 = C (R 4)}} COOCH 2 CH (R 5) OH formula (ii)
(However, R ⁴ and R ⁵ each independently represent H or CH _3. )

  Further, urethane acrylates as described in JP-A-51-37193, JP-B-2-32293, JP-B-2-16765, JP-B-58-49860, JP-B-56-17654 And urethane compounds having an ethylene oxide skeleton described in JP-B-62-39417 and JP-B-62-39418. Furthermore, addition polymerizable compounds having an amino structure or a sulfide structure in the molecule described in JP-A-63-277653, JP-A-63-260909, and JP-A-1-105238 are used. Depending on the case, it is possible to obtain a photopolymerizable composition excellent in the photosensitive speed.

  Other examples include polyester acrylates, epoxy resins and acrylic acid or methacrylic acid as described in JP-A-48-64183, JP-B-49-43191, JP-B-52-30490. Polyfunctional acrylates and methacrylates such as epoxy acrylates reacted with can be mentioned. Further, specific unsaturated compounds described in JP-B-46-43946, JP-B-1-40337, JP-B-1-40336, vinylphosphonic acid compounds described in JP-A-2-25493, and the like Can also be mentioned. In some cases, a structure containing a perfluoroalkyl group described in JP-A-61-22048 is preferably used. Furthermore, the Japan Adhesion Association magazine vol. 20, no. 7, 300-308 pages (1984) can also be used photocurable monomers and oligomers.

About these polymerizable compounds, the details of usage such as the structure, single use or combination, addition amount, etc. can be arbitrarily set according to the performance design of the final lithographic printing plate precursor. For example, it is selected from the following viewpoints.
From the viewpoint of sensitivity, a structure having a large unsaturated group content per molecule is preferable, and in many cases, a bifunctional or higher functionality is preferable. Further, in order to increase the strength of the image area, that is, the cured film, those having three or more functionalities are preferable, and further, different functional numbers and different polymerizable groups (for example, acrylic acid ester, methacrylic acid ester, styrenic compound, vinyl ether). It is also effective to adjust both sensitivity and strength by using a compound of the type).
In addition, the selection and use method of the polymerizable compound is an important factor for the compatibility and dispersibility with other components in the photosensitive layer (for example, binder polymer, polymerization initiator, colorant, etc.) For example, the compatibility may be improved by using a low-purity compound or using two or more kinds in combination. In addition, a specific structure may be selected for the purpose of improving the adhesion of the support or the protective layer described later.

In the present invention, the content of the polymerizable compound (component c) is preferably 5 to 80% by weight, and preferably 25 to 75% by weight with respect to the total nonvolatile components (total solids) in the photosensitive layer. More preferably.
In addition, the use method of the polymerizable compound can be arbitrarily selected from the viewpoints of polymerization inhibition with respect to oxygen, resolution, fogging, refractive index change, surface adhesiveness, etc. Depending on the case, a layer configuration / coating method such as undercoating or overcoating may be performed.

(Component d) Binder polymer The photosensitive layer preferably contains one or more (component d) binder polymers.
As the binder polymer, any of various polymers such as those known in the art to be used in the photosensitive layer of a negative lithographic printing plate precursor can be used without limitation.
The weight average molecular weight of the binder polymer that can be used in the present invention is preferably 2,000 to 1,000,000, and more preferably 10,000 to 200,000. The acid value (mgKOH / g) of the binder polymer is preferably 20 to 400 when determined using a known method.

  Some binder polymers are insoluble in water, but soluble in conventional alkaline developers. Examples of such binder polymers include, for example, European Patent No. 1,182,033, and U.S. Patent Nos. 6,309,792, 6,352,812, 6,569,603, and 6, Polymers derived from (meth) acrylic acid and (meth) acrylic acid esters, polyvinyl acetals, phenolic resins, styrene and its derivatives, such as those described in the specifications of US Pat. ) Polymers derived from, but not limited to, acrylonitrile, N-substituted cyclic imides or maleic anhydride. Vinylcarbazole polymers having pendant N-carbazole moieties such as those described in US Pat. No. 4,774,163, and US Pat. Nos. 6,899,994 and 4,511,645 Also useful are polymers having pendant vinyl groups such as those described in the specification, as well as in EP 1,182,033.

The binder polymer useful in the present invention has a hydrophobic skeleton, and comprises both the following structural repeating units a) and b) or only the structural repeating unit b).
a) a repeating unit having a pendant cyano group directly attached to the hydrophobic backbone, and
b) Repeating units having pendant groups comprising poly (alkylene oxide) segments.
These binder polymers comprise poly (alkylene oxide) segments, preferably poly (ethylene oxide) segments. These binder polymers may be graft copolymers having a main chain polymer and poly (alkylene oxide) side chains, or block copolymers having a block of (alkylene oxide) containing constitutional repeating units and a block of non (alkylene oxide) containing repeating units. Good. Both graft copolymers and block copolymers may further have pendant cyano groups directly attached to the hydrophobic backbone. The alkylene oxide structural unit is preferably an alkylene oxide group having 1 to 6 carbon atoms, and more preferably an alkylene oxide group having 1 to 3 carbon atoms. The alkylene moiety may be linear, branched, or a substituted product thereof. Poly (ethylene oxide) and poly (propylene oxide) segments are preferred, and poly (ethylene oxide) segments are most preferred.

  In some embodiments, the binder polymer may comprise only constitutional repeating units comprising poly (alkylene oxide) segments, and in other embodiments, the polymer binder comprises poly (alkylene oxide) segments. A structural repeating unit and a structural repeating unit having a pendant cyano group directly bonded to the hydrophobic skeleton may be included. By way of example only, such a repeating structural unit may comprise a pendant group comprising a cyano, cyano substituted or cyano terminal alkylene group. The repeating unit can be derived from an ethylenically unsaturated monomer such as, for example, acrylonitrile, methacrylonitrile, methyl cyanoacrylate, ethyl cyanoacrylate, or combinations thereof. However, cyano groups can be introduced into the polymer by other conventional means. Examples of such cyano group-containing binder polymers are described in, for example, US Patent Application Publication No. 2005/003285.

As an example, the binder polymer can be formed by polymerization of a combination or mixture of the following suitable ethylenically unsaturated monomers or macromers.
A) acrylonitrile, methacrylonitrile or a combination thereof,
B) poly (alkylene oxide) esters of acrylic or methacrylic acid, such as poly (ethylene glycol) methyl ether acrylate, poly (ethylene glycol) methyl ester methacrylate or combinations thereof, and
C) As needed, monomers such as acrylic acid, methacrylic acid, styrene, hydroxystyrene, acrylate ester, methacrylate ester, acrylamide, methacrylamide, or a combination of such monomers.

  The amount of poly (alkylene oxide) segment in the binder polymer is preferably 0.5 to 60% by weight, more preferably 2 to 50% by weight, and further preferably 5 to 40% by weight. It is preferably 5 to 20% by weight, particularly preferably. The amount of the (alkylene oxide) segment in the block copolymer is preferably 5 to 60% by weight, more preferably 10 to 50% by weight, and still more preferably 10 to 30% by weight. It is also possible for the polymer binder with poly (alkylene oxide) side chains to be present in the form of discrete particles.

  The binder polymer includes structural repeating units derived from one or more of (meth) acrylic acid, (meth) acrylate, styrene and styrene derivatives, vinyl carbazole, and poly (alkylene glycol) (meth) acrylate. Is preferred. Further, the binder polymer is more preferably one containing structural repeating units derived from two or more of these monomers.

  In the present invention, the binder polymer is particularly preferably a polymer containing a monomer unit derived from a vinyl carbazole compound, most preferably a polymer containing a monomer unit derived from a vinyl carbazole compound and further containing a monomer unit derived from acrylonitrile. preferable. The polymer is preferably an acrylic polymer (also referred to as “acrylic resin”). The acrylic polymer is a polymer obtained by homopolymerizing or copolymerizing a (meth) acrylate compound.

  The binder polymer is preferably 10 to 70% by weight, more preferably 20 to 50% by weight, based on the total solid content of the photosensitive layer.

  The photosensitive layer preferably contains a urethane-acrylic hybrid polymer that is uniformly dispersed in the layer. More preferably, the hybrid polymer is in the form of particles. The weight average molecular weight of the hybrid polymer is 50,000 to 500,000, and the average particle size of the particles is 10 to 10,000 nm, preferably 30 to 500 nm, and more preferably 30 to 150 nm. preferable. These hybrid polymers may be aromatic or aliphatic depending on the structure of the production raw material. Two or more urethane-acrylic hybrid polymer particles may be mixed and used. For example, a Hybridur 570 polymer dispersion and a Hybridur 870 polymer dispersion can be mixed and used.

  The urethane-acrylic hybrid polymer that can be used in the present invention can be generally produced as follows. First, polyol and excess diisocyanate are reacted to obtain a water-dispersed polyurethane prepolymer. The prepolymer preferably has a carboxy group. The prepolymer is then mixed with one or more vinyl monomers, such as acrylate monomers or substituted / unsubstituted styrene monomers, and a tertiary amine is added and dispersed in water. By adding an oil-soluble initiator to the aqueous dispersion and initiating the polymerization, a hybrid polymer dispersed in water in the form of colloidal particles can be obtained. This dispersion is not simply a mixture of a polyurethane dispersion and an acrylic emulsion, but is a polymer in which urethane and acrylic are polymerized simultaneously. The urethane-acrylic hybrid polymer particles are preferably dispersed and stabilized by a negative charge.

  In addition, as described in US Pat. No. 3,684,758, a method of forming an acrylic polymer by first preparing a polyurethane dispersion and adding an acrylic monomer in the presence thereof is urethane-acrylic. This is one useful method for obtaining a hybrid polymer dispersion.

  Another method is a method in which a urethane prepolymer and an acrylic monomer are dispersed together in water, and a urethane degeneracy reaction and acrylic polymerization proceed simultaneously, for example, US Pat. No. 4,644,030, U.S. Pat. No. 5,173,526.

  Details on other methods and properties of urethane-acrylic hybrid polymers are described by Galgoci et al. In JCT Coatings Tech., 2 (13), 28-36 (February 2005).

  As the urethane-acrylic hybrid polymer that can be used in the present invention, it is particularly preferable that the diisocyanate compound used as a raw material for urethane is diphenylmethane diisocyanate, m-tolylene diisocyanate, isophorone diisocyanate, or dicyclohexylmethane diisocyanate. That is, it is particularly preferable that the urethane-acrylic hybrid polymer has a monomer unit derived from a compound selected from the group consisting of diphenylmethane diisocyanate, m-tolylene diisocyanate, isophorone diisocyanate, and dicyclohexylmethane diisocyanate.

  Urethane-acrylic hybrid polymers preferably used in the present invention are urethane-acrylic hybrid polymers such as Hybridur 540, 560, 570, 580, 870, 878, 880 from Air Products and Chemicals (Allentown, Pa.). Commercially available products are available as particle dispersions. In general, these dispersions contain urethane-acrylic hybrid polymer particles as solids of at least 30% by weight and are commercially available surfactants, antifoams, dispersants, preservatives, and additional Are dispersed in an appropriate aqueous medium which can contain a pigment and a water-dispersible organic solvent.

  The urethane-acrylic hybrid polymer is preferably contained in an amount of 10 to 70% by weight, more preferably 10 to 50% by weight, based on the total solid content of the photosensitive layer.

-Other ingredients-
(1) Surfactant In the photosensitive layer according to the invention, a surfactant can be used in order to promote developability and improve the coated surface state.
Examples of the surfactant include nonionic surfactants, anionic surfactants, cationic surfactants, amphoteric surfactants, and fluorosurfactants.

  Preferred surfactants include fluorine-based surfactants containing a perfluoroalkyl group in the molecule. Examples of such fluorosurfactants include anionic types such as perfluoroalkyl carboxylates, perfluoroalkyl sulfonates, and perfluoroalkyl phosphates; amphoteric types such as perfluoroalkyl betaines; Cation type such as trimethylammonium salt; perfluoroalkylamine oxide, perfluoroalkylethylene oxide adduct, oligomer containing perfluoroalkyl group and hydrophilic group, oligomer containing perfluoroalkyl group and lipophilic group, perfluoroalkyl Nonionic types such as an oligomer containing a group, a hydrophilic group and a lipophilic group, and a urethane containing a perfluoroalkyl group and a lipophilic group. Moreover, the fluorine-type surfactant described in each gazette of Unexamined-Japanese-Patent No. 62-170950, 62-226143, and 60-168144 is also mentioned suitably.

Surfactant can be used individually by 1 type or in combination of 2 or more types.
The surfactant content is preferably 0.001 to 10% by weight, more preferably 0.01 to 5% by weight, based on the total solid content of the photosensitive layer.

(2) Colorant In the photosensitive layer according to the invention, a pigment or dye having a large absorption in the visible light region can be used as an image colorant. When a colorant is used, it is easy to distinguish between an image portion after image formation and a non-image portion.
Examples of the pigment used in the present invention include phthalocyanine pigments, azo pigments, carbon black, titanium oxide and the like. In the present invention, it is particularly preferable to use a copper phthalocyanine pigment from the viewpoints of image formation sensitivity and printing durability.
On the other hand, regarding the dye, when the photosensitive layer contains a triphenylalkylborate salt or a tetraphenylborate salt (including an infrared absorbing dye (IR dye) or a counter ion of a polymerization initiator), Although the reason is not clear, the lithographic printing plate precursor may be easily fogged by weak light, and the handling property at the time of plate making may be remarkably inferior. Similarly, it can be usefully used as a colorant.
Specific examples of the dye include oil yellow # 101, oil yellow # 103, oil pink # 312, oil green BG, oil blue BOS, oil blue # 603, oil black BY, oil black BS, oil black T-505 (or more Manufactured by Orient Chemical Co., Ltd.), Victoria Pure Blue, Crystal Violet (CI 42555), Methyl Violet (CI 42535), Ethyl Violet, Rhodamine B (CI 45170B), Malachite Green (CI 42000), Methylene Blue (CI 522015), etc. Mention may be made of the dyes described in JP-A-62-293247.
A suitable addition amount of the colorant is 0.01 to 10% by weight based on the total solid content of the photosensitive layer.

(3) Print-out agent To the photosensitive layer in the invention, a compound that changes color by an acid or a radical can be added in order to produce a print-out image.
As such a compound, for example, various dyes such as diphenylmethane, triphenylmethane, thiazine, oxazine, xanthene, anthraquinone, iminoquinone, azo, and azomethine are effectively used.

  A suitable addition amount of the dye that changes color by an acid or radical is preferably 0.01 to 10% by weight based on the solid content of the photosensitive layer.

(4) Polymerization inhibitor A small amount of a thermal polymerization inhibitor is added to the photosensitive layer in the present invention in order to prevent unnecessary thermal polymerization of the (component c) polymerizable compound during the production or storage of the photosensitive layer. It is preferable to do.
Examples of the thermal polymerization inhibitor include hydroquinone, p-methoxyphenol, di-t-butyl-p-cresol, pyrogallol, t-butylcatechol, benzoquinone, 4,4′-thiobis (3-methyl-6-t- (Butylphenol), 2,2′-methylenebis (4-methyl-6-tert-butylphenol), and N-nitroso-N-phenylhydroxylamine aluminum salt are preferred.
The addition amount of the polymerization inhibitor is preferably 0.01 to 5% by weight with respect to the total solid content of the photosensitive layer.

(5) Higher fatty acid derivatives and the like In the photosensitive layer in the invention, in order to prevent polymerization inhibition by oxygen, higher fatty acid derivatives such as behenic acid and behenic acid amide are added, and in the drying process after coating. It may be unevenly distributed on the surface of the photosensitive layer.
The amount of the higher fatty acid derivative added is preferably 0.1 to 10% by weight based on the total solid content of the photosensitive layer.

(6) Plasticizer The photosensitive layer according to the invention may contain a plasticizer in order to improve developability.
Examples of the plasticizer include phthalates such as dimethyl phthalate, diethyl phthalate, dibutyl phthalate, diisobutyl phthalate, dioctyl phthalate, octyl capryl phthalate, dicyclohexyl phthalate, ditridecyl phthalate, butyl benzyl phthalate, diisodecyl phthalate, diallyl phthalate; Glycol esters such as glycol phthalate, ethyl phthalyl ethyl glycolate, methyl phthalyl ethyl glycolate, butyl phthalyl butyl glycolate, triethylene glycol dicaprylate; Phosphate esters such as tricresyl phosphate and triphenyl phosphate Diisobutyl adipate, dioctyl adipate, dimethyl sebacate, dibutyl sebacate, dioct Ruazereto, aliphatic dibasic acid esters such as dibutyl maleate; polyglycidyl methacrylate, triethyl citrate, glycerin triacetyl ester, butyl laurate in.
The plasticizer content is preferably 30% by weight or less based on the total solid content of the photosensitive layer.

(7) Inorganic particles The photosensitive layer according to the invention may contain inorganic particles in order to improve the cured film strength and developability.
Suitable inorganic particles include, for example, silica, alumina, magnesium oxide, titanium oxide, magnesium carbonate, calcium alginate, or a mixture thereof. These can be used for strengthening the film, enhancing interfacial adhesion by surface roughening, and the like.
The inorganic particles preferably have an average particle size of 5 nm to 10 μm, and more preferably 0.5 μm to 3 μm. Within the above range, it is possible to form a non-image portion excellent in hydrophilicity that is stably dispersed in the photosensitive layer, sufficiently retains the film strength of the photosensitive layer, and does not easily cause stains during printing.
The inorganic particles as described above can be easily obtained as a commercial product such as a colloidal silica dispersion.
The content of inorganic particles is preferably 40% by weight or less, and more preferably 30% by weight or less, based on the total solid content of the photosensitive layer.

(8) Low molecular weight hydrophilic compound The photosensitive layer in the invention may contain a low molecular weight hydrophilic compound because it improves developability without reducing printing durability.
As the low molecular weight hydrophilic compound, for example, as the water-soluble organic compound, ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, dipropylene glycol, tripropylene glycol and the like glycols and ether or ester derivatives thereof, glycerin, Polyhydroxys such as pentaerythritol, organic amines such as triethanolamine and diethanolamine monoethanolamine and salts thereof, organic sulfonic acids such as alkylsulfonic acid, toluenesulfonic acid and benzenesulfonic acid and salts thereof, alkylsulfamic acid and the like Organic sulfamic acids and their salts, organic sulfuric acids and their salts such as alkyl sulfuric acid and alkyl ether sulfuric acid, organic phosphonic acids and their salts such as phenylphosphonic acid, tartaric acid, sulphate , Citric acid, malic acid, lactic acid, gluconic acid, organic carboxylic acids and salts thereof such as amino acids and the like.
Among these, organic sulfonic acids, organic sulfamic acids, organic sulfates such as sodium salts and lithium salts of organic sulfates are preferably used.

  These compounds have a small hydrophobic part structure and almost no surface-active action, and are clearly distinguished from the above-mentioned surfactants in which long-chain alkyl sulfonates and long-chain alkyl benzene sulfonates are used favorably. .

The addition amount of the low molecular weight hydrophilic compound to the photosensitive layer is preferably 0.5 to 20% by weight, more preferably 1 to 10% by weight, based on the total solid content of the photosensitive layer. More preferably, it is 8% by weight. Within the above range, good developability and printing durability can be obtained.
A low molecular weight hydrophilic compound may be used individually by 1 type, and 2 or more types may be mixed and used for it.

(9) Grease-sensitizing agent In the lithographic printing plate precursor that can be used in the present invention, a phosphonium compound can be added as a oil-sensitizing agent to the photosensitive layer and / or the protective layer in order to improve the inking property.
Suitable phosphonium compounds include compounds described in JP-A-2006-297907 and JP-A-2007-50660.

  In addition to the phosphonium compound, a nitrogen-containing compound is also preferable as the sensitizer. Preferable nitrogen-containing compounds may be amine salts and quaternary ammonium salts, and may be imidazolinium salts, benzimidazolinium salts, pyridinium salts, and quinolinium salts. Among these, quaternary ammonium salts and pyridinium salts are preferably used.

  The addition amount of the oil-sensitizing agent to the photosensitive layer or the protective layer is preferably 0.01 to 20% by weight, more preferably 0.05 to 10% by weight in the solid content of each layer, and 0.1 to 5% % Is more preferable. When it is in the above range, good ink fillability can be obtained.

(10) Chain transfer agent or co-sensitizer The photosensitive layer has a known sensitivity called a chain transfer agent or a co-sensitizer having an action such as further improving sensitivity or suppressing polymerization inhibition by oxygen. Compounds may be added.
Examples of such compounds include amines such as MR Sander et al., “Journal of Polymer Society”, Vol. 10, page 3173 (1972), Japanese Examined Patent Publication No. 44-20189, Japanese Unexamined Patent Publication No. 51-82102 Compounds described in JP-A-52-134692, JP-A-59-138205, JP-A-60-84305, JP-A-62-18537, JP-A-64-33104, Research Disclosure 33825 Specifically, N such as triethanolamine, N-phenylglycine, N-phenylaspartic acid, p-dimethylaminobenzoic acid ethyl ester, p-formyldimethylaniline, p-methylthiodimethylaniline, etc. , N-dialkylaniline derivatives and the like.

  Another example of acting as a chain transfer agent is a group of compounds having SH, PH, SiH, GeH in the molecule. These can donate hydrogen to low-activity radical species to generate radicals, or can be oxidized and then deprotonated to generate radicals.

  In particular, thiol compounds (for example, 2-mercaptobenzimidazoles, 2-mercaptobenzthiazoles, 2-mercaptobenzoxazoles, 3-mercaptotriazoles, 5-mercaptotetrazoles, etc.) are chain-transferred to the photosensitive layer. It can be preferably used as an agent. Of these, the thiol compounds described in JP-A-2006-091479 are particularly preferably used. By using this thiol compound as a chain transfer agent, it avoids odor problems and sensitivity reduction due to evaporation from the photosensitive layer or diffusion to other layers, and it has excellent storage stability and high sensitivity and high printing durability. A lithographic printing plate precursor is obtained.

  The amount of these sensitizers or chain transfer agents used is preferably 0.01 to 20% by weight, more preferably 0.1 to 15% by weight, based on the total solid content of the photosensitive layer. More preferably, it is 1.0 to 10% by weight.

[Formation of photosensitive layer]
The photosensitive layer in the present invention is preferably formed by dispersing or dissolving the necessary components described above in a solvent to prepare a coating solution, which is coated on a support and dried.
Solvents used here include ethylene dichloride, cyclohexanone, methyl ethyl ketone, methanol, ethanol, propanol, ethylene glycol monomethyl ether, 1-methoxy-2-propanol, 2-methoxyethyl acetate, 1-methoxy-2-propyl acetate, dimethoxy Examples include ethane, methyl lactate, ethyl lactate, N, N-dimethylacetamide, N, N-dimethylformamide, tetramethylurea, N-methylpyrrolidone, dimethyl sulfoxide, sulfolane, γ-butyllactone, toluene, water, and the like. However, the present invention is not limited to this.
A solvent can be used individually by 1 type or in mixture of 2 or more types.
The solid content concentration of the coating solution is preferably 1 to 50% by weight.

  The photosensitive layer in the present invention may be prepared by preparing a plurality of coating solutions in which the same or different components are dispersed or dissolved in the same or different solvents, and repeating a plurality of coating and drying steps to form a multilayered photosensitive layer. Is possible.

The photosensitive layer coating amount (solid content) on the support obtained after coating and drying varies depending on the application, but is preferably 0.3 to 3.0 g / m ² . Within the above range, good sensitivity and good film properties of the photosensitive layer can be obtained.
Various methods can be used as a coating method. Examples thereof include bar coater coating, spin coating, spray coating, curtain coating, dip coating, air knife coating, blade coating, and roll coating.

[Protective layer]
The lithographic printing plate precursor that can be used in the present invention preferably comprises a protective layer (overcoat layer) on the photosensitive layer.
The protective layer is preferably a layer having functions such as preventing the formation of scratches in the photosensitive layer and preventing ablation during high-illuminance laser exposure in addition to the function of suppressing the image formation inhibition reaction by blocking oxygen.
Hereinafter, components constituting the protective layer will be described.

  Usually, the exposure processing of a lithographic printing plate is performed in the atmosphere. The image forming reaction in the photosensitive layer caused by the exposure process can be inhibited by low molecular compounds such as oxygen and basic substances present in the atmosphere. The protective layer prevents low molecular compounds such as oxygen and basic substances from entering the photosensitive layer, and as a result, suppresses image formation inhibition reaction in the air. Therefore, the property desired for the protective layer is to reduce the permeability of low-molecular compounds such as oxygen, furthermore, the transparency of light used for exposure is good, the adhesiveness with the photosensitive layer is excellent, and It can be easily removed in the development process after exposure. The protective layer having such characteristics is described in, for example, US Pat. No. 3,458,311 and Japanese Patent Publication No. 55-49729.

As a material used for the protective layer, either a water-soluble polymer or a water-insoluble polymer can be appropriately selected and used. Specifically, for example, polyvinyl alcohol, modified polyvinyl alcohol, polyvinyl pyrrolidone, polyvinyl imidazole, polyacrylic acid, polyacrylamide, partially saponified product of polyvinyl acetate, ethylene-vinyl alcohol copolymer, water-soluble cellulose derivative, gelatin, Examples thereof include water-soluble polymers such as starch derivatives and gum arabic, and polymers such as polyvinylidene chloride, poly (meth) acrylonitrile, polysulfone, polyvinyl chloride, polyethylene, polycarbonate, polystyrene, polyamide, and cellophane.
These may be used in combination of two or more as required.

  A relatively useful material among the above materials includes water-soluble polymer compounds having excellent crystallinity. Specifically, water-soluble acrylic resins such as polyvinyl alcohol, polyvinyl pyrrolidone, polyvinyl imidazole, and polyacrylic acid, gelatin, gum arabic, and the like are suitable. Among these, water can be applied as a solvent, and printing Polyvinyl alcohol, polyvinyl pyrrolidone, and polyvinyl imidazole are preferable from the viewpoint that they are easily removed by the fountain solution. Among them, polyvinyl alcohol (PVA) gives the best results for basic properties such as oxygen barrier properties and development removability.

The polyvinyl alcohol that can be used in the protective layer may be partially substituted with an ester, an ether, and an acetal as long as it contains a substantial amount of an unsubstituted vinyl alcohol unit having the required water solubility. Similarly, a part may contain other copolymerization components. For example, various hydrophilic modification sites such as anion modification sites modified with anions such as carboxyl groups and sulfo groups, cation modification sites modified with cations such as amino groups and ammonium groups, silanol modification sites, and thiol modification sites are randomly selected. Polyvinyl alcohol having various degrees of polymerization, the anion-modified site, the cation-modified site, the silanol-modified site, the thiol-modified site, the alkoxyl-modified site, the sulfide-modified site, and the ester modification of vinyl alcohol and various organic acids. Polyvinyl alcohol having various degrees of polymerization having various modified sites such as a site, an ester-modified site of the anion-modified site and alcohols, an epoxy-modified site, etc. at the polymer chain end is also preferably used.
Among these, anion-modified polyvinyl alcohol is most preferable because of good dispersion stability in the developer. This anion-modified polyvinyl alcohol is preferably contained in an amount of 10 to 50% by weight, more preferably 20 to 40% by weight, based on the total solid content of the protective layer.

Preferred examples of these polyvinyl alcohols include compounds having a degree of hydrolysis (degree of saponification) of 71 to 100 mol% and a degree of polymerization of 300 to 2400. Specifically, PVA-105, PVA-110, PVA-117, PVA-117H, PVA-120, PVA-124, PVA-124H, PVA-CS, PVA-CST, PVA-HC manufactured by Kuraray Co., Ltd. , PVA-203, PVA-204, PVA-205, PVA-210, PVA-217, PVA-220, PVA-224, PVA-217EE, PVA-217E, PVA-220E, PVA-224E, PVA-405, PVA -420, PVA-613, L-8 and the like.
Moreover, as modified polyvinyl alcohol, KL-318, KL-118, KM-618, KM-118, SK-5102, CKS-50 having an anion-modified site, C-318, C-118 having a cation-modified site, CM-318, M-205 having terminal thiol modification site, M-115, MP-103 having terminal sulfide modification site, MP-203, MP-102, MP-202, ester modification site with higher fatty acid Examples thereof include HL-12E, HL-1203, and other reactive silane-modified R-1130, R-2105, R-2130, and the like.

Further, the protective layer preferably contains an inorganic layered compound, that is, a compound that is an inorganic compound, has a layered structure, and has a flat plate shape. By using such an inorganic layered compound in combination, the oxygen barrier property is further increased, and the film strength of the protective layer is further improved and scratch resistance is improved, and the matte property can be imparted to the protective layer. it can.
The inorganic stratiform compound, for example, the _{formula: A (B, C) 2} ~ 5 D 4 O 10 (OH, F, O) 2 ( However, A is Li, K, Na, Ca, Mg or an organic cation B and C each independently represents Fe (II), Fe (III), Mn, Al, Mg or V, and D represents Si or Al.) Examples include mica group, talc, teniolite, montmorillonite, saponite, hectorite, zirconium phosphate represented by the formula: 3MgO.4SiO.H ₂ O.

Among the mica compounds, examples of natural mica include muscovite, soda mica, phlogopite, biotite and sericite. Further, as the synthetic mica, non-swelling mica such as fluorine phlogopite mica ₃ (AlSi ₃ O ₁₀ ) F ₂ , potassium tetrasilicon mica KMg _2.5 Si ₄ O ₁₀ ) F ₂ , and Na tetrasilicic mica NaMg _2.5 ( Si ₄ O ₁₀ ) F ₂ , Na or Li Teniolite (Na, Li) Mg ₂ Li (Si ₄ O ₁₀ ) F ₂ , Montmorillonite Na or Li Hectorite (Na, Li) _1/8 Mg _2/5 Li Examples thereof include swelling mica such as _1/8 (Si ₄ O ₁₀ ) F ₂ . Synthetic smectites are also useful.

Among the mica compounds, fluorine-based swellable mica, which is a synthetic layered compound, is particularly useful. That is, swellable clay minerals such as mica, montmorillonite, saponite, hectorite, bentonite, etc. have a laminated structure composed of unit crystal lattice layers with a thickness of about 10 to 15 mm, and metal atom substitution in the lattice is other than Significantly greater than viscous minerals. As a result, the lattice layer has a shortage of positive charge, and Li ⁺ , Na ⁺ , Ca ²⁺ , Mg ²⁺ , amine salts, quaternary ammonium salts, phosphonium salts, sulfonium salts, etc. Adsorbs organic cation cations. These layered compounds swell with water. If shear is applied in this state, it will easily cleave and form a stable sol in water. Bentonite and swellable synthetic mica have a strong tendency and are useful in the present invention. In particular, swellable synthetic mica is preferably used from the viewpoint of availability and uniformity of quality.

  The shape of the layered compound is a flat plate, and from the viewpoint of diffusion control, the thinner the better, the larger the plane size as long as it does not hinder the smoothness of the coated surface or the transmittance of actinic rays. . Therefore, the aspect ratio is 20 or more, preferably 100 or more, particularly preferably 200 or more. The aspect ratio is the ratio of the thickness to the major axis of the particle, and can be measured from, for example, a projected view of the particle by a micrograph. The larger the aspect ratio, the greater the effect that can be obtained.

  The average particle diameter of the layered compound is preferably 0.3 to 20 μm, more preferably 0.5 to 10 μm, and particularly preferably 1 to 5 μm. Within the above range, the permeation of oxygen and moisture is sufficiently suppressed, the dispersion stability in the coating solution is sufficient, and stable coating can be performed. The average thickness of the layered compound particles is preferably 0.1 μm or less, more preferably 0.05 μm or less, and still more preferably 0.01 μm or less. For example, among the inorganic layered compounds, the swellable synthetic mica that is a representative compound preferably has a thickness of 1 to 50 nm and a surface size of 1 to 20 μm.

  When the inorganic layered compound particles having such a large aspect ratio are contained in the protective layer, the coating film strength is improved, and the permeation of oxygen and moisture can be effectively prevented. Deterioration is prevented, and even when stored for a long time under high-humidity conditions, the storage stability of the planographic printing plate precursor does not deteriorate due to changes in humidity, and the storage stability is excellent.

Next, an example of a general dispersion method when a layered compound is used for the protective layer will be described.
First, 5 to 10 parts by weight of the swellable layered compound mentioned above as a preferred layered compound is added to 100 parts by weight of water, and the mixture is thoroughly swelled and swollen, and then dispersed by a disperser. Examples of the disperser used here include various mills that disperse mechanically by applying a direct force, a high-speed stirring disperser having a large shearing force, a disperser that provides high-intensity ultrasonic energy, and the like. Specifically, ball mill, sand grinder mill, visco mill, colloid mill, homogenizer, tisol bar, polytron, homomixer, homo blender, ketdy mill, jet agitator, capillary emulsifier, liquid siren, electrostrictive ultrasonic generator, An emulsifying device having a Paulman whistle can be used. A dispersion containing 5 to 10% by weight of the inorganic layered compound dispersed by the above method is highly viscous or gelled, and has very good storage stability.
When preparing a coating solution for a protective layer using this dispersion, it is preferably prepared by diluting with water and stirring sufficiently, and then blending with a binder solution.

  It is preferable that content of the inorganic stratiform compound in a protective layer is 5/1-1/100 by weight ratio with respect to the quantity of the binder polymer used for a protective layer. Even when a plurality of kinds of inorganic layered compounds are used in combination, the total amount of these inorganic layered compounds is preferably matched to the above weight ratio.

  As other additives for the protective layer, for example, glycerin, dipropylene glycol, propionamide, cyclohexanediol, sorbitol and the like are added in an amount corresponding to several weight% with respect to the water-soluble or water-insoluble polymer to give flexibility. be able to. Moreover, well-known additives, such as a water-soluble (meth) acrylic polymer and a water-soluble plasticizer, can be added for improving the physical properties of the film.

Furthermore, the protective layer in the present invention is formed using a coating solution for a protective layer as described below, and this coating solution is known for improving the adhesion to the photosensitive layer and the stability of the coating solution over time. These additives may be added.
That is, the protective layer coating solution includes an anionic surfactant, a nonionic surfactant, a cationic surfactant, and a fluorosurfactant for improving coating properties, specifically, sodium alkyl sulfate, alkyl sulfonic acid. Anionic surfactants such as sodium; amphoteric surfactants such as alkylaminocarboxylates and alkylaminodicarboxylates; nonionic surfactants such as polyoxyethylene alkylphenyl ether can be added.
The addition amount of the surfactant can be 0.1 to 100% by weight based on the water-soluble or water-insoluble polymer.

  In order to improve the adhesion to the image area, for example, JP-A-49-70702 and British Patent Application No. 1303578 disclose an acrylic polymer in a hydrophilic polymer mainly composed of polyvinyl alcohol. It is described that sufficient adhesiveness can be obtained by mixing 20 to 60% by weight of a system emulsion, a water-insoluble vinylpyrrolidone-vinyl acetate copolymer and the like and laminating on a photosensitive layer. Any of these known techniques can be used in the present invention.

  Furthermore, other functions can be imparted to the protective layer. For example, by adding a colorant (for example, a water-soluble dye) that is excellent in the transparency of infrared rays used for exposure and that can efficiently absorb light of other wavelengths, safe light is not caused. Suitability can be improved.

The protective layer is formed by applying and drying a protective layer coating solution prepared by dispersing or dissolving the protective layer component in a solvent on the photosensitive layer.
The coating solvent can be appropriately selected in relation to the binder, but when a water-soluble polymer is used, it is preferable to use distilled water or purified water.

The method for applying the protective layer is not particularly limited, and a known method such as the method described in US Pat. No. 3,458,311 or Japanese Patent Publication No. 55-49729 can be applied. .
Specifically, for example, when the protective layer is formed, a blade coating method, an air knife coating method, a gravure coating method, a roll coating coating method, a spray coating method, a dip coating method, a bar coating method, or the like is used.

The coating amount of the protective layer is preferably 0.02 to 3 g / m ² , more preferably 0.05 to 1 g / m ^{2 in} terms of the coating amount after drying. Most preferably, it is in the range of 1 to 0.4 g / m ² .

[Support]
The support used for the lithographic printing plate precursor is not particularly limited as long as it is a dimensionally stable plate. For example, paper, paper laminated with plastic (eg, polyethylene, polypropylene, polystyrene, etc.), metal plate (eg, aluminum, zinc, copper, etc.), plastic film (eg, cellulose diacetate, cellulose triacetate, cellulose propionate) Cellulose butyrate, cellulose acetate butyrate, cellulose nitrate, polyethylene terephthalate, polyethylene, polystyrene, polypropylene, polycarbonate, polyvinyl acetal, etc.), and paper or plastic films on which the above-mentioned metals are laminated or deposited.
A preferable support includes a polyester film and an aluminum plate. Among them, an aluminum plate that has good dimensional stability and is relatively inexpensive is particularly preferable.

  The aluminum plate is a pure aluminum plate, an alloy plate containing aluminum as a main component and containing a trace amount of foreign elements, or a plastic laminated on a thin film of aluminum or an aluminum alloy. Examples of the foreign element contained in the aluminum alloy include silicon, iron, manganese, copper, magnesium, chromium, zinc, bismuth, nickel, and titanium. The content of foreign elements in the alloy is preferably 10% by weight or less. In the present invention, a pure aluminum plate is preferable, but completely pure aluminum is difficult to manufacture in terms of refining technology, and therefore may contain a slightly different element. The composition of the aluminum plate is not specified, and a publicly known material can be used as appropriate.

  Prior to using the aluminum plate, it is preferable to perform surface treatment such as roughening treatment or anodizing treatment. By the surface treatment, it is easy to improve hydrophilicity and secure adhesion between the photosensitive layer and the support. Prior to roughening the aluminum plate, a degreasing treatment with a surfactant, an organic solvent, an alkaline aqueous solution or the like for removing rolling oil on the surface is performed as desired.

The surface roughening treatment of the aluminum plate is performed by various methods. For example, mechanical surface roughening treatment, electrochemical surface roughening treatment (surface roughening treatment for dissolving the surface electrochemically), chemical treatment, etc. Surface roughening treatment (roughening treatment that chemically selectively dissolves the surface).
As a method for the mechanical surface roughening treatment, a known method such as a ball polishing method, a brush polishing method, a blast polishing method, or a buff polishing method can be used. Moreover, the transcription | transfer method which transfers an uneven | corrugated shape with the roll which provided the unevenness | corrugation in the rolling stage of aluminum can also be used.
Examples of the electrochemical surface roughening treatment include a method in which an alternating current or a direct current is used in an electrolytic solution containing an acid such as hydrochloric acid or nitric acid. Another example is a method using a mixed acid as described in JP-A-54-63902.

  The surface-roughened aluminum plate is subjected to an alkali etching treatment using an aqueous solution of potassium hydroxide, sodium hydroxide or the like, if necessary, further neutralized, and if desired, wear resistant. In order to increase the anodic oxidation treatment.

As the electrolyte used for the anodizing treatment of the aluminum plate, various electrolytes that form a porous oxide film can be used. For example, sulfuric acid, hydrochloric acid, oxalic acid, phosphoric acid, chromic acid or a mixed acid thereof is preferably used. Among these, sulfuric acid, oxalic acid, and phosphoric acid are more preferable, and phosphoric acid is still more preferable. The concentration of those electrolytes is appropriately determined depending on the type of electrolyte.
The conditions for anodizing treatment vary depending on the electrolyte used and cannot be specified. However, the electrolyte concentration is 1 to 80% by weight, the solution temperature is 5 to 70 ° C., the current density is 5 to 60 A / dm ² , and the voltage is 1. It is preferable that it is -100V and electrolysis time is 10 seconds-5 minutes. The amount of the anodized film formed is preferably from 1.0 to 5.0 g / m ^2, and more preferably 1.5 to 4.0 g / m ^2. Within the above range, good printing durability and good scratch resistance of the non-image area of the planographic printing plate can be obtained.

  As the support used in the present invention, the substrate having the above-mentioned surface treatment and having an anodized film may be used as it is. However, in order to further improve the adhesiveness with the upper layer, hydrophilicity, dirt resistance, heat insulation and the like. If necessary, an aqueous solution containing a hydrophilic compound and a micropore enlargement treatment or sealing treatment of an anodized film described in JP 2001-253181 A or JP 2001-322365 A The surface hydrophilization treatment to be immersed can be appropriately selected and performed. Of course, these enlargement processing and sealing processing are not limited to those described above, and any conventionally known method can be performed. For example, as the sealing treatment, in addition to the vapor sealing, a single treatment with fluorinated zirconic acid, a treatment with sodium fluoride, and a vapor sealing with addition of lithium chloride are possible.

  The sealing treatment used in the present invention is not particularly limited, and a conventionally known method can be used. Among them, sealing treatment with an aqueous solution containing an inorganic fluorine compound, sealing treatment with water vapor, and sealing with hot water are particularly preferable. Hole treatment is preferred. This will be described in detail below.

<1> Sealing treatment with an aqueous solution containing an inorganic fluorine compound As the inorganic fluorine compound used for the sealing treatment with an aqueous solution containing an inorganic fluorine compound, a metal fluoride is preferably exemplified.
Specifically, for example, sodium fluoride, potassium fluoride, calcium fluoride, magnesium fluoride, sodium fluoride zirconate, potassium fluoride zirconate, sodium fluoride titanate, potassium fluoride titanate, zircon fluoride Ammonium acid, ammonium fluorinated titanate, fluorinated zirconic acid, fluorinated titanic acid, hexafluorosilicic acid, nickel fluoride, iron fluoride, fluorinated phosphoric acid, and ammonium fluorinated phosphate. Among these, sodium fluorinated zirconate, sodium fluorinated titanate, fluorinated zirconic acid, and fluorinated titanic acid are preferable.

  The concentration of the inorganic fluorine compound in the aqueous solution is preferably 0.01% by weight or more, and more preferably 0.05% by weight or more in terms of sufficiently sealing the micropores of the anodized film. Further, in terms of stain resistance, the content is preferably 1% by weight or less, and more preferably 0.5% by weight or less.

  It is preferable that the aqueous solution containing the inorganic fluorine compound further contains a phosphate compound. When the phosphate compound is contained, the hydrophilicity of the surface of the anodized film is improved, so that the developability and stain resistance can be improved.

Suitable examples of the phosphate compound include phosphates of metals such as alkali metals and alkaline earth metals.
Specifically, for example, zinc phosphate, aluminum phosphate, ammonium phosphate, diammonium hydrogen phosphate, ammonium dihydrogen phosphate, monoammonium phosphate, monopotassium phosphate, monosodium phosphate, dihydrogen phosphate Potassium, dipotassium hydrogen phosphate, calcium phosphate, sodium ammonium hydrogen phosphate, magnesium hydrogen phosphate, magnesium phosphate, ferrous phosphate, ferric phosphate, sodium dihydrogen phosphate, sodium phosphate, hydrogen phosphate Disodium, lead phosphate, diammonium phosphate, calcium dihydrogen phosphate, lithium phosphate, phosphotungstic acid, ammonium phosphotungstate, sodium phosphotungstate, ammonium phosphomolybdate, sodium phosphomolybdate, sodium phosphite , Tripolyphosphate Potassium, and sodium pyrophosphate. Of these, sodium dihydrogen phosphate, disodium hydrogen phosphate, potassium dihydrogen phosphate, and dipotassium hydrogen phosphate are preferable.
The combination of the inorganic fluorine compound and the phosphate compound is not particularly limited, but the aqueous solution contains at least sodium zirconate fluoride as the inorganic fluorine compound, and contains at least sodium dihydrogen phosphate as the phosphate compound. It is preferable to do.

  The concentration of the phosphate compound in the aqueous solution is preferably 0.01% by weight or more, more preferably 0.1% by weight or more, from the viewpoint of improving developability and stain resistance. In terms of solubility, it is preferably 20% by weight or less, and more preferably 5% by weight or less.

The ratio of each compound in the aqueous solution is not particularly limited, but the weight ratio of the inorganic fluorine compound and the phosphate compound is preferably 1/200 to 10/1, and preferably 1/30 to 2/1. Is more preferable.
The temperature of the aqueous solution is preferably 20 ° C. or higher, more preferably 40 ° C. or higher, 100 ° C. or lower, more preferably 80 ° C. or lower.
The aqueous solution preferably has a pH of 1 or more, more preferably has a pH of 2 or more, preferably has a pH of 11 or less, and more preferably has a pH of 5 or less.
The method for sealing with an aqueous solution containing an inorganic fluorine compound is not particularly limited, and examples thereof include an immersion method and a spray method. These may be used alone or in combination, or may be used in combination of two or more.
Of these, the dipping method is preferred. When processing using the dipping method, the processing time is preferably 1 second or longer, more preferably 3 seconds or longer, 100 seconds or shorter, and 20 seconds or shorter. More preferred.

<2> Sealing treatment with water vapor Sealing treatment with water vapor includes, for example, a method in which pressurized or normal pressure water vapor is contacted with the anodized film continuously or discontinuously.
The temperature of the water vapor is preferably 80 ° C. or higher, more preferably 95 ° C. or higher, and preferably 105 ° C. or lower.
The water vapor pressure is preferably in a range (1.008 × 10 ^{5 to} 1.043 × 10 ⁵ Pa) from (atmospheric pressure (1 atm) −50 mmAq) to (atmospheric pressure + 300 mmAq).
The time for which the water vapor is contacted is preferably 1 second or longer, more preferably 3 seconds or longer, 100 seconds or shorter, and more preferably 20 seconds or shorter.

<3> Sealing treatment with hot water Examples of the sealing treatment with hot water include a method in which an aluminum plate on which an anodized film is formed is immersed in hot water.
The hot water may contain an inorganic salt (for example, phosphate) or an organic salt.
The temperature of the hot water is preferably 80 ° C. or higher, more preferably 95 ° C. or higher, and preferably 100 ° C. or lower.
Further, the time of immersion in hot water is preferably 1 second or longer, more preferably 3 seconds or longer, 100 seconds or shorter, more preferably 20 seconds or shorter.

  The hydrophilization treatment is described in US Pat. Nos. 2,714,066, 3,181,461, 3,280,734 and 3,902,734. There are alkali metal silicate methods. In this method, the support is subjected to immersion treatment or electrolytic treatment with an aqueous solution such as sodium silicate. In addition, a method of treating with potassium fluoride zirconate described in JP-B 36-22063, a method of treating with polyacrylic acid as described in US Pat. No. 3,136,636 And a method of treating with polyvinylphosphonic acid as described in US Pat. Nos. 3,276,868, 4,153,461 and 4,689,272. . Among these, alkali metal silicate treatment and polyvinylphosphonic acid treatment are preferable, and polyvinylphosphonic acid treatment is more preferable.

  When using a support having insufficient surface hydrophilicity such as a polyester film as the support in the present invention, it is preferable to apply a hydrophilic layer to make the surface hydrophilic. The hydrophilic layer is at least selected from the group consisting of beryllium, magnesium, aluminum, silicon, titanium, boron, germanium, tin, zirconium, iron, vanadium, antimony and transition metals described in JP-A-2001-199175. Obtained by crosslinking or pseudo-crosslinking an organic hydrophilic polymer described in JP-A-2002-79772 or a hydrophilic layer formed by coating a coating solution containing one elemental oxide or hydroxide colloid. Hydrophilic layer having an organic hydrophilic matrix, hydrophilic layer having an inorganic hydrophilic matrix obtained by sol-gel conversion comprising hydrolysis and condensation reaction of polyalkoxysilane, titanate, zirconate or aluminate, or metal oxide Hydrophilic film composed of an inorganic thin film having a surface containing It is preferred. Among these, a hydrophilic layer formed by applying a coating solution containing a silicon oxide or hydroxide colloid is preferable.

  Moreover, when using a polyester film etc. as a support body in this invention, it is preferable to provide an antistatic layer in the hydrophilic layer side of a support body, the opposite side, or both sides. In the case where the antistatic layer is provided between the support and the hydrophilic layer, it also contributes to improving the adhesion with the hydrophilic layer. As the antistatic layer, a polymer layer in which metal oxide particles and a matting agent are dispersed as described in JP-A-2002-79772 can be used.

The support preferably has a center line average roughness of 0.10 to 1.2 μm. Within the above range, good adhesion to the photosensitive layer, good printing durability and good stain resistance can be obtained.
The thickness of the support is preferably from 0.1 to 0.6 mm, more preferably from 0.15 to 0.4 mm.

[Back coat layer]
After surface treatment is performed on the support or after an undercoat layer (described later) is formed, a backcoat layer can be provided on the back surface of the support, if necessary.
Examples of the back coat layer include hydrolysis and polycondensation of organic polymer compounds described in JP-A-5-45885, organic metal compounds or inorganic metal compounds described in JP-A-6-35174, and the like. Preferable examples include a coating layer made of a metal oxide. Of these, the use of silicon alkoxy compounds such as Si (OCH ₃ ) ₄ , Si (OC ₂ H ₅ ) ₄ , Si (OC ₃ H ₇ ) ₄ , and Si (OC ₄ H ₉ ) ₄ makes the raw material inexpensive. It is preferable in that it is easily available.

(Undercoat layer)
In the lithographic printing plate precursor used in the invention, an undercoat layer can be provided between the photosensitive layer and the support, if necessary.
The undercoat layer is easy to cause peeling of the photosensitive layer from the support in the unexposed area, so that developability is improved. In addition, in the case of infrared laser exposure, since the undercoat layer functions as a heat insulating layer, the heat generated by exposure does not diffuse to the support and can be used efficiently, so that the sensitivity can be increased. There is.

  Specific examples of the undercoat layer compound include silane coupling agents having addition-polymerizable ethylenically unsaturated bonds described in JP-A-10-282679, and JP-A-2-304441. Preferable examples include phosphorus compounds having an ethylenically unsaturated bond described in 1.

The compound used for the undercoat layer preferably has adsorptivity to the support surface. The presence or absence of adsorptivity to the support surface can be determined by the following method, for example.
A coating night is prepared by dissolving the test compound in a readily soluble solvent, and the coating night is coated and dried on the support so that the coating amount after drying is 30 mg / m ² . Next, after the support coated with the test compound is sufficiently washed with an easily soluble solvent, the residual amount of the test compound that has not been removed by washing is measured to calculate the support adsorption amount. Here, the measurement of the remaining amount may be performed by directly quantifying the amount of the remaining compound or by quantifying the amount of the test compound dissolved in the cleaning liquid. The compound can be quantified by, for example, fluorescent X-ray measurement, reflection spectral absorbance measurement, liquid chromatography measurement and the like. The compound having support adsorptivity is a compound that remains at 1 mg / m ² or more even after the above-described washing treatment.

In order to give the compound used for the undercoat layer the adsorptivity to the support surface, it can be carried out by introducing a substrate adsorptive group (hereinafter also simply referred to as “adsorptive group”). The adsorptive group is a substance (for example, metal, metal oxide) present on the support surface, or a functional group (for example, hydroxy group) and a chemical bond (for example, ionic bond, hydrogen bond, coordinate bond, intermolecular). It is a functional group that can cause binding by force. The adsorptive group is preferably an acid group or a cationic group.
The acid group preferably has an acid dissociation constant (pKa) of 7 or less. Examples of the acid group are phenolic hydroxy group, carboxyl group, —SO ₃ H, —OSO ₃ H, —PO ₃ H ₂ , —OPO ₃ H ₂ , —CONHSO ₂ —, —SO ₂ NHSO ₂ , —COCH _2. COCH ₃ is mentioned. Among them, -OPO ₃ H _2, and, are particularly preferred -PO ₃ H _2. These acid groups may be metal salts.
The cationic group is preferably an onium group. Examples of the onium group include an ammonium group, a phosphonium group, an arsonium group, a stibonium group, an oxonium group, a sulfonium group, a selenonium group, a stannonium group, and an iodonium group. Among these, an ammonium group, a phosphonium group, and a sulfonium group are preferable, an ammonium group and a phosphonium group are more preferable, and an ammonium group is most preferable.

  Preferable examples of the monomer having an adsorptive group used when synthesizing a polymer compound suitable as a compound for the undercoat layer include compounds represented by the following formula (U1) or formula (U2).

In formulas (U1) and (U2), R ¹ , R ² and R ³ each independently represents a hydrogen atom, a halogen atom or an alkyl group having 1 to 6 carbon atoms.
R ¹ , R ² and R ³ are each independently preferably a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, more preferably a hydrogen atom or an alkyl group having 1 to 3 carbon atoms. Preferably, it is a hydrogen atom or a methyl group. R ² and R ³ are particularly preferably hydrogen atoms.
Z is a functional group adsorbed on the surface of the support and contains the adsorptive group.

L represents a single bond or a divalent linking group.
L is a divalent aliphatic group (alkylene group, substituted alkylene group, alkenylene group, substituted alkenylene group, alkynylene group, substituted alkynylene group), divalent aromatic group (arylene group, substituted arylene group) or divalent Or an oxygen atom (—O—), a sulfur atom (—S—), an imino (—NH—), a substituted imino (—NR—, R is an aliphatic group, an aromatic group Or a heterocyclic group) or a combination of carbonyl (—CO—).

The divalent aliphatic group may have a cyclic structure or a branched structure.
1-20 are preferable, as for the carbon atom number of the said bivalent aliphatic group, 1-15 are more preferable, and 1-10 are still more preferable. The divalent aliphatic group is preferably a saturated aliphatic group rather than an unsaturated aliphatic group. Furthermore, the divalent aliphatic group may have a substituent, and examples of the substituent include a halogen atom, a hydroxy group, an aromatic group, and a heterocyclic group.
6-20 are preferable, as for the carbon atom number of the said bivalent aromatic group, 6-15 are more preferable, and 6-10 are still more preferable. The divalent aromatic group may have a substituent, and examples of the substituent include a halogen atom, a hydroxy group, an aliphatic group, an aromatic group, and a heterocyclic group.
The divalent heterocyclic group preferably has a 5-membered or 6-membered ring as a heterocycle. In addition, another heterocyclic ring, an aliphatic ring, or an aromatic ring may be condensed with the heterocyclic ring. The divalent heterocyclic group may have a substituent, and examples of the substituent include a halogen atom, a hydroxy group, an oxo group (═O), a thioxo group (═S), an imino group (═NH ), A substituted imino group (= N—R, R is an aliphatic group, an aromatic group or a heterocyclic group), an aliphatic group, an aromatic group, or a heterocyclic group.

L is preferably a divalent linking group containing a plurality of polyoxyalkylene structures. The polyoxyalkylene structure is more preferably a polyoxyethylene structure. In other words, L preferably contains — (OCH ₂ CH ₂ ) _n — (n is an integer of 2 or more).
In the formula (U1), X represents an oxygen atom (—O—) or imino (—NH—). X is preferably an oxygen atom.
In the formula (U2), Y represents a carbon atom or a nitrogen atom. When Y is a nitrogen atom and L is linked to Y to form a quaternary pyridinium group, Z itself is adsorbable, so Z is not essential, and Z may be a hydrogen atom.

  Examples of typical compounds represented by formula (U1) or formula (U2) are shown below. In the following compounds, Me represents a methyl group, and Et represents an ethyl group.

The compound used for the undercoat layer preferably has a hydrophilic group.
Examples of the hydrophilic group include a hydroxy group, a carboxyl group, a carboxylate group, a hydroxyethyl group, a polyoxyethyl group, a hydroxypropyl group, a polyoxypropyl group, an amino group, an aminoethyl group, an aminopropyl group, an ammonium group, Preferred examples include an amide group, a carboxymethyl group, a sulfo group, and a phosphoric acid group. Of these, a sulfo group exhibiting high hydrophilicity is preferable.

  Specific examples of the monomer having a sulfo group include methallyloxybenzenesulfonic acid, allyloxybenzenesulfonic acid, allylsulfonic acid, vinylsulfonic acid, p-styrenesulfonic acid, methallylsulfonic acid, acrylamide t-butylsulfonic acid, Examples include 2-acrylamido-2-methylpropanesulfonic acid, sodium salt of (3-acryloyloxypropyl) butylsulfonic acid, and amine salt. Among them, 2-acrylamido-2-methylpropanesulfonic acid sodium salt is preferable from the viewpoint of hydrophilic performance and synthetic handling.

  The compound used for the undercoat layer preferably has a crosslinkable group. The crosslinkable group can improve the adhesion to the image area. In order to impart crosslinkability to the compound used in the undercoat layer, a crosslinkable functional group such as an ethylenically unsaturated bond is introduced into the side chain of the polymer compound, or the polar substituent of the polymer compound is countercharged. Or a compound having an ethylenically unsaturated bond can be introduced by forming a salt structure.

  Examples of polymers having an ethylenically unsaturated bond in the side chain are polymers of esters or amides of acrylic acid or methacrylic acid, wherein the ester or amide residue (R of —COOR or —CONHR) is ethylenic. Mention may be made of polymers having unsaturated bonds.

Examples of the residue (the R) having an ethylenically unsaturated _{bond, -CH = CH 2, -C (} CH 3) = CH 2, - (CH 2) n CR 1 = CR 2 R 3, - ( _{CH 2 O) n CH 2 CR} 1 = CR 2 R 3, - (CH 2 CH 2 O) n CH 2 CR 1 = CR 2 R 3, - (CH 2) n NH-CO-O-CH 2 CR 1 ^{= CR 2 R 3, - (} CH 2) n -O-CO-CR 1 = CR 2 R 3, and _{(CH 2 CH 2 O) 2} -X ( wherein, R ¹ to R ³ are each a hydrogen atom Represents a halogen atom or an alkyl group having 1 to 20 carbon atoms, an aryl group, an alkoxy group or an aryloxy group, and R ¹ and R ² or R ³ may be bonded to each other to form a ring. Represents an integer of 1 to 10. X represents a dicyclopentadienyl residue.
Specific examples of the ester residue include —CH═CH ₂ , —C (CH ₃ ) ═CH ₂ , —CH ₂ CH═CH ₂ (described in Japanese Patent Publication No. 7-21633), —CH. _{2 CH 2 O-CH 2 CH} = CH 2, -CH 2 C (CH 3) = CH 2, -CH 2 CH = CH-C 6 H 5, -CH 2 CH 2 OCOCH = CH-C 6 H 5, _{-CH 2 CH 2 NHCOO-CH 2} CH = CH 2, and CH ₂ CH (wherein, X represents a dicyclopentadienyl residue.) ₂ O-X and the like.
Specific examples of the amide residue include —CH═CH ₂ , —C (CH ₃ ) ═CH ₂ , —CH ₂ CH═CH ₂ , —CH ₂ CH ₂ O—Y (wherein Y is a cyclohexene residue) And —CH ₂ CH ₂ OCO—CH═CH ₂ .
As the monomer having a crosslinkable group of the polymer compound for the undercoat layer, an ester or amide of acrylic acid or methacrylic acid having the crosslinkable group is preferable.

  The content of the crosslinkable group in the undercoat layer compound (content of radically polymerizable ethylenically unsaturated bond by iodine titration) is preferably 0.1 to 10.0 mmol per 1 g of the compound. It is more preferably 0 to 7.0 mmol, and particularly preferably 2.0 to 5.5 mmol. Within the above range, both good sensitivity and dirtiness and good storage stability can be obtained.

  Preferred compounds for the undercoat layer in the present invention include compounds having a substrate adsorptive group and a crosslinkable group. Such a compound includes a compound obtained by polymerizing at least a monomer having an adsorptive group and a monomer having a crosslinkable group.

The polymer compound for the undercoat layer preferably has a weight average molecular weight of 5,000 or more, more preferably 10,000 to 300,000, and a number average molecular weight of 1,000 or more. More preferably, it is 2,000-250,000. The polydispersity (weight average molecular weight / number average molecular weight) is preferably 1.1 to 10.
The polymer compound for the undercoat layer may be any of a random polymer, a block polymer, a graft polymer, etc., but is preferably a random polymer.

The undercoat compound may be used alone or in combination of two or more.
The undercoat layer coating solution is obtained by dissolving the above undercoat compound in an organic solvent (for example, methanol, ethanol, acetone, methyl ethyl ketone, etc.) and / or water.
The undercoat layer coating solution may contain an infrared absorber.
Various known methods can be used as a method of applying the undercoat layer coating solution to the support. Examples thereof include bar coater coating, spin coating, spray coating, curtain coating, dip coating, air knife coating, blade coating, and roll coating.
The coating amount (solid content) of the undercoat layer is preferably 0.1-100 mg / m ^2, more preferably 1 to 30 mg / m ^2.

  The lithographic printing plate obtained by the plate making method of the lithographic printing plate of the present invention is mounted on a plate cylinder of a printing machine, for example, and is supplied with dampening water and printing ink, so that a large number of printed materials can be suitably obtained. Can be provided.

  EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples. However, the present invention is not limited to the following examples unless it exceeds the gist thereof. Unless otherwise specified, “part” and “%” are based on weight. Further, the numbers on the lower right of the parentheses in the chemical structure of the resin represent the molar ratio unless otherwise specified.

<Explanation of terms of chemical substances used in polymer particle synthesis and photosensitive layer coating solution>
PEGMA: 50% by weight aqueous solution of poly (ethylene glycol) methyl ether methacrylate available from Sigma-Aldrich (St. Louis, Missouri), average number average molecular weight (Mn) ˜2,080
Hybridur 580: Urethane-acrylic hybrid polymer dispersion (40%) available from Air Products and Chemicals
Hybridur 870: Urethane-acrylic hybrid polymer dispersion (40%) available from Air Products and Chemicals
SR399: Dipentaerythritol pentaacrylate available from Sartomer Japan, Inc. NK-Ester A-DPH: Dipentaerythritol hexaacrylate available from Nakamura Synthetic Chemical Industry, Inc. CD9053: Sartomer Japan, Inc. ) Ester compounds of trifunctional organic acids available from: Fluor N2900: Surfactant available from Cytnix • Masurf FS-1520: Fluoroalkyl group-containing amphoteric surfactant available from Mason Chemical

<Synthesis of binder polymer 1>
In a three-neck flask equipped with a magnetic stirrer, water bath, and N ₂ inlet, AIBN (2,2′-azobis (isobutyronitrile), Vazo-64, obtained from Du Pont, 1.6 parts), Methyl methacrylate (20 parts), acrylonitrile (24 parts), N-vinylcarbazole (20 parts, obtained from Polymer Dajac), methacrylic acid (16 parts), and dimethylacetamide (DMAC, 320 parts) were added. The reaction mixture was heated to 60 ° C. and stirred overnight (16 hours) under N ₂ protection. As a result, a 20% DMAC solution of binder polymer 1 was obtained.
The composition of the binder polymer 1 is methyl methacrylate / acrylonitrile / N-vinylcarbazole / methacrylic acid = 21/48/11/20 (molar ratio), and the molecular weight was measured using gel permeation chromatography in tetrahydrofuran. Mw (weight average molecular weight) was about 52,000.

<Synthesis of binder polymer 2>
200 parts of the DMAC solution of binder polymer 1 synthesized as described above was weighed, and potassium hydroxide (2.6 parts) in water (20 parts) was slowly added thereto to form a viscous liquid. After the mixture was stirred for 10 minutes, allyl bromide (6.7 parts) was added and the mixture was stirred at 55 ° C. for 3 hours. 36% concentrated hydrochloric acid (6 parts) in DMAC (20 parts) was added to the flask and the reaction mixture was stirred for an additional 3 hours. The resulting reaction mixture was then slowly added dropwise with stirring into a mixture of 12,000 parts ice water and 20 parts concentrated hydrochloric acid. The resulting precipitate was filtered and washed with 1,608 parts propanol followed by 2,000 parts water. A white powder was obtained after filtration. The powder was dried at room temperature (10-25 ° C.) overnight and then at 50 ° C. for 3 hours to give about 40 parts of binder polymer 2 solids.
The composition of the binder polymer 2 was methyl methacrylate / acrylonitrile / N-vinyl carbazole / allyl methacrylate = 21/48/11/20 (molar ratio), and Mw measured in the same manner as described above was about 57,000. .

<Synthesis of binder polymer 3>
A 20% DMAC solution of binder polymer 3 was obtained in the same manner as in the synthesis of binder polymer 1 except that acrylonitrile was not used, the amount of methyl methacrylate was 65 parts, and the amount of DMAC was 400 parts.
The composition of the binder polymer 3 was methyl methacrylate / N-vinylcarbazole / methacrylic acid = 69/11/20 (molar ratio), and Mw measured in the same manner as described above was about 55,000.

<Synthesis of binder polymer 4>
A 20% DMAC solution of binder polymer 4 was obtained in the same manner as in the synthesis of binder polymer 1 except that N-vinylcarbazole was not used, the amount of methyl methacrylate was 30 parts, and the amount of DMAC was 280 parts. It was.
The composition of the binder polymer 4 was methyl methacrylate / acrylonitrile / methacrylic acid = 32/48/20 (molar ratio), and Mw measured in the same manner as described above was about 50,000.

<Synthesis of binder polymer 5>
DMAC (100.7 parts) and PEGMA (50% aqueous solution, 20 parts) are placed in a 4-neck ground glass flask equipped with a heating mantle, temperature controller, mechanical stirrer, reflux condenser, dropping funnel, and nitrogen supply port, and nitrogen is added. The reaction mixture was heated to 80 ° C. under a stream of air. Premixed DMAC (125 parts), vinylcarbazole (25 parts), acrylonitrile (35 parts), styrene (20 parts), methacrylic acid (10 parts), and AIBN (0.5 parts, Vazo-64). It was added at 80 ° C. over 2 hours, and then the reaction was continued for 15 hours while adding 1.25 parts of Vazo-64. From the quantitative measurement of the nonvolatile content, the monomer reaction rate was 99% or more. The resulting polymer solution is reprecipitated with 6,000 parts of water / ice (3: 1) with high agitation and the precipitated polymer powder is filtered and then at room temperature for 24 hours at 43 ° C. It was dried for 2 days to obtain a powder of binder polymer 5. The yield was 95%, and the acid value was 69 mgKOH / g (theoretical value: 65).
The composition of the binder polymer 5 is PEGMA / acrylonitrile / vinyl carbazole / styrene / methacrylic acid = 0.5 / 60/12/17/11 (molar ratio), and the Mw measured in the same manner as above is about 100,000. there were.

<Synthesis of urethane-acrylic hybrid polymer 1>
Formrez 55-56 (poly (neopentyl adipate), a polyol available from Witco Chemical, Mw about 2,000) (100 parts) was charged to a nitrogen purged reactor. To this was added methylenedicyclohexyl diisocyanate (90.6 parts) and a tin catalyst 10% DABCO T-12 (dibutyltin dilaurate available from Air Products and Chemicals) (0.25 parts). The mixture was stirred at 92 ° C. for 3 hours. With constant stirring, dimethylolpropionic acid (14.8 parts) was added followed by 1-methyl-2-pyrrolidinone (54.6 parts). The mixture was held at 92 ° C. for an additional 5 hours.
The prepolymer was cooled to 75 ° C. and butyl methacrylate (141.6 parts) and 1,6-hexanediol diacrylate (0.88 parts) were added. After the mixture was stirred for 15 minutes, the amount of free NCO was measured, and the amount of NCO was almost 0%. The mixture was then cooled to 25 ° C. and triethylamine (10.66 parts) was added and allowed to react for 1 hour. After neutralization, the prepolymer / monomer mixture was dispersed in deionized water (489.97 parts). In order to extend the chain, ethylenediamine (8.97 parts) was dissolved in deionized water (16.67 parts), added to the reactor and allowed to react for 2 hours. The free radical initiator Vazo-64 (AIBN available from Du Pont) (0.88 parts) dissolved in 1-methyl-2-pyrrolidinone (6.93 parts) was then added and butyl methacrylate (31 .44 parts) and a mixture of 2-hydroxyethyl methacrylate (29.12 parts) was also added. After 5 minutes, the dispersion was heated to 75 ° C. and held there for 2 hours.
After the polymerization was completed, the dispersion was filtered through a filter to obtain a urethane-acrylic hybrid polymer 1.
Mw of the obtained urethane-acrylic hybrid polymer 1 was estimated to be about 150,000. Moreover, when the particle size was measured using a laser diffraction / scattering particle size distribution measuring apparatus LA-910 manufactured by Horiba, Ltd., ma (average diameter of area distribution) was 360 nm, mv (volume distribution of The average diameter (the center of gravity of the distribution) was 440 nm.

<Synthesis of urethane-acrylic hybrid polymer 2>
Formrez 55-56 (poly (neopentyl adipate), a polyol available from Witco Chemical Co., Mw about 2,000) (200.1 parts) was charged to a nitrogen purged reactor. To this was added methylenedicyclohexyl diisocyanate (105.3 parts) and 10% DABCO T-12 tin catalyst (dibutyltin dilaurate available from Air Products and Chemicals) (0.52 parts). The mixture was stirred at 92 ° C. for 3 hours. With constant stirring, dimethylolpropionic acid (26.8 parts) was added followed by 1-methyl-2-pyrrolidinone (110 parts). The mixture was held at 92 ° C. for an additional 5 hours.
The prepolymer was cooled to 75 ° C. and methyl methacrylate (199.7 parts) was added. After the mixture was stirred for 15 minutes, the free NCO% was measured and the NCO content was about 1-1.5%, the mixture was cooled to 25 ° C., triethylamine (19.5 parts) was added and 1 hour. Reacted. After neutralization, methyl methacrylate (64.2 parts) and 2-hydroxyethyl methacrylate (64.2 parts) were added and stirred for 5 minutes. The prepolymer was then dispersed in deionized water (800.2 parts). In order to terminate the chain, diethanolamine (18.6 parts) was dissolved in deionized water (32.5 parts), added to the reactor and allowed to react for 2 hours. The free radical initiator Vazo-67 (2,2′-azobis (2-methylbutyronitrile) available from Du Pont) dissolved in 1-methyl-2-pyrrolidinone (13.52 parts) ( 3.94 parts) and the thiol chain transfer agent 1-dodecylthiol (20.2 parts). After 5 minutes, the dispersion was heated to 75 ° C. and held there for 2 hours to obtain urethane-acrylic hybrid polymer 2.
Mw of the obtained urethane-acrylic hybrid polymer 2 was estimated to be about 30,000. The particle size measured by the above method was ma = 230 nm and mv = 350 nm.

<Synthesis of urethane-acrylic hybrid polymer 3>
A urethane-acrylic hybrid polymer 3 was synthesized in the same manner as the synthesis of the urethane-acrylic hybrid polymer 1 except that the diisocyanate compound used was replaced with methylenedicyclohexyl diisocyanate by diphenylmethane diisocyanate (MDI).
Mw of the obtained urethane-acrylic hybrid polymer 3 was estimated to be about 100,000. The particle size measured by the above method was ma = 300 nm and mv = 380 nm.

<Synthesis of urethane-acrylic hybrid polymer 4>
A urethane-acrylic hybrid polymer 4 was synthesized in the same manner as in the synthesis of the urethane-acrylic hybrid polymer 1 except that the diisocyanate compound used was replaced with m-tolylene diisocyanate (TDI) from methylene dicyclohexyl diisocyanate.
Mw of the obtained urethane-acrylic hybrid polymer 4 was estimated to be about 130,000. The particle size measured by the above method was ma = 320 nm and mv = 400 nm.

<Synthesis of urethane-acrylic hybrid polymer 5>
A urethane-acrylic hybrid polymer 5 was synthesized in the same manner as the synthesis of the urethane-acrylic hybrid polymer 1 except that the diisocyanate compound used was replaced by methylenedicyclohexyl diisocyanate to isophorone diisocyanate (IpDI).
Mw of the obtained urethane-acrylic hybrid polymer 5 was estimated to be about 150,000. The particle size measured by the above method was ma = 340 nm and mv = 450 nm.

<Synthesis of urethane-acrylic hybrid polymer 6>
Urethane-acrylic hybrid polymer 6 was synthesized in the same manner as in the synthesis of urethane-acrylic hybrid polymer 1 except that the diisocyanate compound used was replaced by methylenedicyclohexyl diisocyanate with hexamethylene diisocyanate (HMDI).
Mw of the obtained urethane-acrylic hybrid polymer 6 was estimated to be about 180,000. The particle size measured by the above method was ma = 420 nm and mv = 520 nm.

(Examples 1-124 and Comparative Examples 1-30)
<Preparation of lithographic printing plate precursor (1)>
(1) Production of support (1) In order to remove rolling oil on the surface of a 0.3 mm thick aluminum plate (material JIS A 1050), degreasing is performed at 50 ° C. for 30 seconds using a 10 wt% sodium aluminate aqueous solution. After the treatment, the aluminum surface is grained with three bundle-planted nylon brushes having a bristle diameter of 0.3 mm and a pumice-water suspension (specific gravity 1.1 g / cm ³ ) having a median diameter of 25 μm. Washed well. This plate was etched by being immersed in a 25 wt% sodium hydroxide aqueous solution at 45 ° C. for 9 seconds, washed with water, further immersed in a 20 wt% nitric acid aqueous solution at 60 ° C. for 20 seconds, and washed with water. The etching amount of the grained surface at this time was about 3 g / m ² .

Next, an electrochemical roughening treatment was performed continuously using an alternating voltage of 60 Hz. The electrolytic solution at this time was a 1% by weight nitric acid aqueous solution (containing 0.5% by weight of aluminum ions) and a liquid temperature of 50 ° C. The AC power source waveform is electrochemical roughening treatment using a trapezoidal rectangular wave alternating current with a time ratio TP of 0.8 msec until the current value reaches a peak from zero, a duty ratio of 1: 1, and a trapezoidal rectangular wave alternating current. Went. Ferrite was used for the auxiliary anode. The current density was 30 A / dm ² at the peak current value, and 5% of the current flowing from the power source was shunted to the auxiliary anode. The amount of electricity in the nitric acid electrolysis was 175 C / dm ² when the aluminum plate was the anode. Then, water washing by spraying was performed.

Subsequently, nitric acid electrolysis was performed with an aqueous solution of 0.5% by weight hydrochloric acid (containing 0.5% by weight of aluminum ions) and an electrolytic solution having a liquid temperature of 50 ° C. under the condition of an electric quantity of 50 C / dm ² when the aluminum plate was the anode. In the same manner as above, an electrochemical surface roughening treatment was performed, followed by washing with water by spraying. Next, a 2.5 g / m ² DC anodized film with a current density of 15 A / dm ² was provided on this plate as a 15 wt% sulfuric acid aqueous solution (containing 0.5 wt% aluminum ions) as an electrolyte, and then washed with water. , Dried.
Furthermore, 100 degreeC water vapor | steam was sprayed on said anodic oxide film for 8 second by the pressure of 1.033 * 10 < ⁵ > Pa, and the sealing process was performed.
Then, in order to ensure the hydrophilic property of a non-image part, the silicate process was performed for 6 second at 75 degreeC using 2.5 weight% # 3 sodium silicate aqueous solution. The adhesion amount of Si was 10 mg / m ² . Then, it washed with water and the support body (1) was obtained. The centerline average roughness (Ra) of this substrate was measured using a needle having a diameter of 2 μm and found to be 0.51 μm.

(2) Formation of undercoat layer Next, on the support (1), the following undercoat layer coating solution (1) is applied so that the dry coating amount is 20 mg / m ² , and a support having an undercoat layer. Was made.

[Coating liquid for undercoat layer (1)]
-Undercoat layer compound (1) having the following structure: 0.18 parts-Methanol: 55.24 parts-Water: 6.15 parts

(3) Formation of photosensitive layer A photosensitive layer coating solution (1) having the following composition was bar-coated on the undercoat layer, followed by oven drying at 100 ° C. for 60 seconds, and a photosensitive layer having a dry coating amount of 1.0 g / m ² . Formed.
The photosensitive layer coating solution (1) was prepared by adding 1.00 part of an aqueous dispersion of urethane-acrylic hybrid polymer used in the present invention described in Table 4 to 10.467 parts of the following photosensitive solution (1). And mixed and stirred.

[Photosensitive solution (1)]
-Binder polymer listed in Table 4 0.240 parts as solid content-0.030 parts of the following infrared absorber (1)-0.162 parts of the following polymerization initiator (A)-Polymerizable compound (Tris (acryloyloxyethyl) Isocyanurate)
(NK Ester A-9300, manufactured by Shin-Nakamura Chemical Co., Ltd.) 0.192 parts • Dipentaerythritol pentaacrylate 0.062 parts • Pionine A-20 (manufactured by Takemoto Yushi Co., Ltd.) 0.055 parts • Benzyl- dimethyl - 0.018 parts octyl ammonium-PF ₆ salt shown below fluorocarbon surfactant (1) 0.008 parts Methyl ethyl ketone 1.091 parts 1-methoxy-2-propanol 8.609 parts

(3) Formation of Protective Layer After the protective layer coating solution (1) having the following composition is bar-coated on the photosensitive layer, it is oven-dried at 120 ° C. for 60 seconds to provide a dry coating amount of 0.15 g / m ² . A layer was formed to obtain a lithographic printing plate precursor (1).

[Coating liquid for protective layer (1)]
-1.5 parts of the following inorganic layered compound dispersion (1)-Polyvinyl alcohol (CKS50, sulfonic acid modified by Nippon Synthetic Chemical Industry Co., Ltd.,
Saponification degree 99 mol% or more, polymerization degree 300) 6% by weight aqueous solution 0.55 parts polyvinyl alcohol (Puraray manufactured by Kuraray Co., Ltd., saponification degree 81.5 mol%,
Degree of polymerization 500) 6% by weight aqueous solution 0.03 part. Surfactant manufactured by Nippon Emulsion Co., Ltd. (Emalex 710) 1% by weight aqueous solution 0.86 part. Ion-exchanged water 6.0 parts

-Preparation of inorganic layered compound dispersion (1)-
6.4 parts of synthetic mica Somasif ME-100 (manufactured by Coop Chemical Co., Ltd.) was added to 193.6 parts of ion-exchanged water, and dispersed using an homogenizer until the average particle size (laser scattering method) became 3 μm. The aspect ratio of the obtained dispersed particles was 100 or more.

<Preparation of lithographic printing plate precursor (2)>
(1) Production of Support (2) An aluminum plate that has been subjected to electrochemical surface roughening in the production of support (1) is prepared by using 2.5M phosphoric acid as an electrolyte, voltage 50V, and maximum current density 2A. in / dm ² to provide a DC anodic oxide film of 1.5 g / m ^2, washed with water and dried.
Then, 100 degreeC water vapor | steam was sprayed on said anodic oxide film for 15 second with the pressure of 1.033 * 10 < ⁵ > Pa, and the sealing process was performed.
Then, it was immersed in a polyvinyl phosphonic acid aqueous solution with a liquid temperature of 50 ° C. and 0.4 wt% for 10 seconds, washed with water and dried to obtain a support (2).

(2) Formation of undercoat layer, photosensitive layer and protective layer Using the support (2), the photosensitive layer coating solution (1) was changed to the following photosensitive layer coating solution (2) without providing an undercoat layer. Bar coating, oven drying at 82 ° C. for 90 seconds to provide a photosensitive layer with a dry coating amount of 1.2 g / m ² , and the protective layer coating solution (1) was changed to the following protective layer coating solution (2) A lithographic printing plate precursor (2) was obtained in the same manner as for the lithographic printing plate precursor (1) except that a bar coating was applied and a protective layer having a dry coating amount of 0.4 g / m ² was provided.

[Photosensitive layer coating solution (2)]
-Binder polymer described in Table 1 or Table 2. 1.75 parts as solid content-Urethane-acrylic hybrid polymer described in Table 1 or Table 2
2.34 parts as solid content, SR399 2.66 parts, NK-Ester A-DPH 2.66 parts, CD9053 0.53 parts, bis-t-butylphenyliodonium tetraphenylborate 0.96 parts Fluor N2900 11 parts Pigment 1 0.73 parts Infrared absorbing agent (2) 0.27 parts Ion-exchanged water 13.77 parts 1-methoxy-2-propanol 48.18 parts 2-butyrolactone 13.77 parts 2 -Butanone 61.94 parts

Disperbyk167: Dispersant available from Byk Chemie

[Coating liquid for protective layer (2)]
-Polyvinyl alcohol (PVA-405 manufactured by Kuraray Co., Ltd., saponification degree: 81.5 mol%,
Degree of polymerization 500) 6% by weight aqueous solution 66.33 parts, Masurf 1520 0.02 parts, ion-exchanged water 8.65 parts

<Preparation of lithographic printing plate precursor (3)>
(1) Production of Support (3) The polyacrylic acid treatment in the production of the support (2) was changed to a polyvinylphosphonic acid treatment. That is, the aluminum plate that had been subjected to the treatment before the polyvinylphosphonic acid treatment in the production of the support (2) was immersed in a polyacrylic acid aqueous solution at a liquid temperature of 25 ° C. and 1.0 wt% for 8 seconds, washed with water, It dried and obtained the support body (3).

(2) Formation of photosensitive layer Without providing an undercoat layer on the support (3), the photosensitive layer coating solution (1) was changed to the following photosensitive layer coating solution (3) and applied by bar coating at 90 ° C. and 90 ° C. Oven-dried for ² seconds to provide a photosensitive layer with a dry coating amount of 1.5 g / m ² , and the protective layer coating solution (1) was changed to the following protective layer coating solution (3) and applied to the bar. A lithographic printing plate precursor (3) was obtained in the same manner as in the lithographic printing plate precursor (1) except that a protective layer of 1 g / m ² was provided.

[Photosensitive layer coating solution (3)]
-Binder polymer listed in Table 3 8.50 parts as solid content-1: 2 reaction product of hexamethylene diisocyanate and hydroxyethyl acrylate 6.00 parts-1: 2 reaction product of hexamethylene diisocyanate and pentaerythritol tetraacrylate 6.00 parts-The following polymerization initiator (B) 0.70 parts-The following infrared absorber (3) 0.20 parts-N-phenyliminodiacetic acid 0.25 parts-Crystal violet 0.35 parts-FluorN2900 08 parts 1-methoxy-2-propanol 88.32 parts 2-butyrolactone 22.08 parts 2-butanone 110.40 parts

[Coating liquid for protective layer (3)]
-Polyvinyl alcohol (PVA-105 manufactured by Kuraray Co., Ltd., saponification degree of 98 mol% or more,
Degree of polymerization 500) 6% by weight aqueous solution 66.33 parts Surfactant manufactured by Nippon Emulsion Co., Ltd. (Emalex 710) 1% by weight aqueous solution 0.86 parts ion-exchanged water 12.60 parts

<Exposure>
Each of the lithographic printing plate precursors (1) and (2) was subjected to an external drum rotation speed of 1,000 rpm, a laser output of 70%, and a resolution of 2,400 dpi using a FUJIFILM Corporation Luxel PLANETTER T-6000III equipped with an infrared semiconductor laser. The exposure was performed under the following conditions.
On the other hand, the planographic printing plate precursor (3) was exposed with a Trend setter 3244VX manufactured by Creo Corporation equipped with an infrared semiconductor laser under the conditions of an output of 10 W and an outer drum rotating speed of 150 rpm and a resolution of 2,400 dpi. The exposure image includes a solid image and a fine line image, respectively.

<Development processing>
In Examples 1-124 and Comparative Examples 1-30 except Examples 33, 50, 87, and 124, the exposed original plate was developed using the automatic developing apparatus shown in FIG. In FIG. 1, development was performed in the developing unit 14, washing in the water washing unit 16, and desensitization in the desensitization processing unit 18. The developers used are shown in Tables 1 to 4 below. The followings were used for the washing water and the desensitizing liquid.
The developer was recycled through a cartridge filter “TCW-75N-PPS” (mesh diameter: 75 μm) manufactured by Advantech Toyo Co., Ltd. using a pump.

[Flushing water used in the washing process]
After adding tap water, it was circulated using a pump and reused. Once used for water washing, it was reused after passing through a cartridge filter “TCW-75N-PPS” (mesh diameter: 75 μm) manufactured by Advantech Toyo Co., Ltd.

[Gum solution for desensitizing process]
A gum solution “FN-6” manufactured by FUJIFILM Corporation was diluted with an equal amount of tap water and used.

  In Examples 33, 50, 87, and 124, the exposed original plate was developed using the automatic developing apparatus shown in FIG. 2 and then dried with a drier. The developers used are shown in Tables 1 to 4 below.

<Evaluation>
The odor of the developer, the developability of development processing (non-image area removability), the development sludge due to the development removal component of the development processing section, and the fine line reproducibility (sensitivity) of the lithographic printing plate prepared by the development process Printing durability in printing was evaluated in the following manner. The evaluation results are shown in Tables 5 to 8.

(1) Odor of developer The solvent odor around the automatic developing apparatus during the above development processing was sensory-evaluated by 10 evaluators, and the average score was ranked according to the following index.
A: There was almost no solvent odor or it did not mind and was very favorable.
B: Although there was a slight solvent odor, it was an acceptable level.
C: The solvent odor was strong and the level was unacceptable for practical use.
D: The solvent odor was extremely strong and poor.

(2) Developability Each of the non-image area of the lithographic printing plate after the development treatment and each support (uncoated substrate that has been subjected to surface treatment) used for the preparation of each lithographic printing plate precursor is placed in a Gretag densitometer. Then, the cyan density (C density) was measured, and the optical density difference (ΔD) was obtained. If the developability is good, ΔD is 0 to 0.02, and is acceptable up to 0.04. If this value is exceeded, the photosensitive layer components remaining on the non-image area will be adversely affected such as ink smearing during printing, which is an unacceptable level for practical use.

(3) Development sludge The above development treatment is performed by running a large number of lithographic printing plate precursors so that the lithographic printing plate precursor is 20 m ² per liter of the developing solution. The developing sludge discharged from the water and deposited on the bottom of the developing bath was observed. Further, the circulating filter cartridge was taken out and the developing sludge trapped on the filter surface was observed. Sensory evaluation of the amount and state of the developing sludge was performed visually, and ranking was performed according to the following indices.
A: The developing bath bottom and the filter surface were very good with almost no developing sludge.
B: There was no developing sludge at the bottom of the developing bath, and a slight amount of developing sludge was observed on the filter surface, but it was considered to have almost no effect on the cleaning property of the developing bath and the filter life, and was at an acceptable level.
C: Development sludge was observed at the bottom of the developing bath and the filter surface, which was considered to have an influence on the cleaning property of the developing bath and the filter life, and was at an unacceptable level for practical use.
D: A large amount of development sludge was generated at the bottom of the developing bath and the filter surface, which was inferior.

(4) Sensitivity As a method for evaluating the sensitivity of the lithographic printing plate precursor, a test chart in which the thickness of the exposed fine line image (the fine line (thin line-like image part in the non-image part) is changed every 5 μm from 5 μm to 50 μm ) Was visually evaluated on the planographic printing plate to which thin line of thickness could be reproduced on the planographic printing plate after the development treatment. That is, the smaller the value, the better the image formation up to the finer thin line, and the higher the sensitivity.

(5) Printing durability The developed lithographic printing plate was attached to the plate cylinder of a printing machine LITHRONE 26 manufactured by Komori Corporation. Equality-2 (manufactured by FUJIFILM Corporation) / tap water = 2/98 (volume ratio) dampening water and Values-G (N) black ink (manufactured by Dainippon Ink & Chemicals, Inc.) Printing was started by supplying dampening water and ink by the standard automatic printing start method of LITHRONE 26, and printing was performed on Tokuhishi Art (76.5 kg) paper at a printing speed of 10,000 sheets per hour. While the plate surface is washed with Multi Cleaner E (Fuji Film Co., Ltd. plate cleaner) every 5,000 sheets, the ink density in the image area decreases and the 5% dot density of the 20 μm FM screen is 0 from the start of printing. When the decrease was 5%, it was judged that the printing was completed, and the number of printed sheets at that time was evaluated as the number of printed sheets.

  From the results of Tables 5 to 8, in any of Examples 1 to 124 using the lithographic printing plate making method of the present invention, the odor of the developer, the developability, and the development sludge due to the development removal component are good. It can be seen that a lithographic printing plate excellent in sensitivity and printing durability can be obtained.

[Composition of developer used in development step]
<Developer 1 (pH: 7.0)>
-Amount of 10,000 parts combined with other components-Ethylene glycol mono-n-hexyl ether Amounts listed in Tables 1 to 4 (octanol / water partition coefficient = 1.86, solubility in water = 1.0 g / 100ml of water)
Nonionic surfactant shown in Exemplified Compound B-14 Amounts listed in Tables 1 to 4

<Developer 2 (pH: 7.0)>
・ Water Amount of 10,000 parts combined with other components ・ Ethylene glycol mono-n-butyl ether Amounts listed in Tables 1 to 4 (octanol / water partition coefficient = 0.83, solubility in water = mixing)
-Nonionic surfactant shown to exemplary compound B-14 Amount described in Tables 1 to 4

<Developer 3 (pH: 7.0)>
・ Water Amount of 10,000 parts combined with other components ・ Propylene glycol mono-n-butyl ether Amounts listed in Tables 1 to 4 (octanol / water partition coefficient = no data, solubility in water = 4.4 g / 100 ml water) )
-Nonionic surfactant shown to exemplary compound B-14 Amount described in Tables 1 to 4

<Developer 4 (pH: 7.0)>
・ Water Amount of 10,000 g combined with other components ・ Diethylene glycol mono-2-ethylhexyl ether Amounts listed in Tables 1 to 4 (octanol / water partition coefficient = no data, solubility in water = 0.3 g / 100 ml of water)
-Nonionic surfactant shown to exemplary compound B-14 Amount described in Tables 1 to 4

<Developer 5 (pH: 7.0)>
・ Water Amount of 10,000 parts combined with other components ・ Ethylene glycol mono-t-butyl ether Amounts listed in Tables 1 to 4 (octanol / water partition coefficient = 0.36, solubility in water = mixing)
-Nonionic surfactant shown to exemplary compound B-14 Amount described in Tables 1 to 4

<Developer 6 (pH: 7.0)>
・ Water: 10,000 parts in combination with other ingredients ・ 1,000 parts of benzyl alcohol (octanol / water partition coefficient = 1.1, solubility in water = 4.0 g / 100 ml of water)
-Nonionic surfactant shown to exemplary compound B-14 Amount described in Tables 1 to 4 Developer 6 did not become a single phase but separated into two phases.

<Developer 7 (pH: 7.0)>
・ Water Amount of 10,000 parts combined with other ingredients ・ 1,000 parts of ethylene glycol monophenyl ether (octanol / water partition coefficient = 1.2, solubility in water = 2.7 g / 100 ml of water)
-Nonionic surfactant shown in Exemplified Compound B-14 Amounts listed in Tables 1 to 4 Developer 7 was separated into two phases instead of a single phase.

<Developer 8 (pH: 7.0)>
・ Water Amount of 10,000 parts combined with other components ・ Ethylene glycol mono-n-hexyl ether Amount described in Table 1 to Table 4 ・ Nonionic surfactant shown in Exemplified Compound B-12 Table 1 to Table 4 The amount described in

<Developer 9 (pH: 7.0)>
・ Water Amount of 10,000 parts combined with other components ・ Ethylene glycol mono-n-hexyl ether Amount described in Tables 1 to 4 ・ Nonionic surfactant shown in Exemplified Compound B-15 Tables 1 to 4 The amount described in

<Developer 10 (pH: 7.0)>
・ Water Amount of 10,000 g combined with other components ・ Ethylene glycol mono-n-hexyl ether Amount described in Tables 1 to 4 ・ Nonionic surfactants shown in Exemplified Compound B-26 Tables 1 to 4 As stated

<Developer 11 (pH: 7.0)>
-Amount of 10,000 parts combined with other components-Ethylene glycol mono-n-hexyl ether Amount described in Tables 1 to 4-Nonionic surfactants shown in Exemplified Compound B-7 Tables 1 to 4 The amount described in

<Developer 12 (pH: 7.0)>
-Amount of 10,000 parts combined with other components-Ethylene glycol mono-n-hexyl ether Amount described in Tables 1 to 4-Nonionic surfactant shown in Exemplified Compound B-11 Tables 1 to 4 The amount described in

<Developer 13 (pH: 7.0)>
・ Water Amount of 10,000 parts combined with other components ・ Ethylene glycol mono-n-hexyl ether Amounts listed in Tables 1 to 4 ・ Emalex 710
(Nonionic surfactant manufactured by Nippon Emulsion Co., Ltd.) 500 parts The developer 13 was a single phase but increased in viscosity.

<Developer 14 (pH: 7.0)>
-Amount of 10,000 parts combined with other components-Ethylene glycol mono-n-hexyl ether Amounts listed in Tables 1 to 4-Pluronic L31
(Nonionic surfactant manufactured by Asahi Denka Kogyo Co., Ltd.) 500 parts Developer 14 did not become a single phase but separated into two phases.

<Developer 15 (pH: 7.0)>
-Amount of 10,000 parts combined with other components-Ethylene glycol mono-n-hexyl ether Amounts listed in Tables 1 to 4-Perex NBL (anionic surfactant manufactured by Kao Corporation) 500 parts Developer 6 did not become a single phase but separated into two phases.

<Developer 16 (pH: 7.0)>
・ Water Amount of 10,000 parts when combined with other components ・ Ethylene glycol mono-n-hexyl ether Amounts listed in Tables 1 to 4
(Nippon Emulsifier Co., Ltd. anionic surfactant) 500 parts

<Developer 17 (pH: 7.0)>
・ Water Amount of 10,000 parts combined with other components ・ Ethylene glycol mono-n-hexyl ether Amounts listed in Tables 1 to 4 ・ Pionine B111 (cationic surfactant manufactured by Takemoto Yushi Co., Ltd.) 500 parts Development Liquid 17 did not become a single phase but separated into two phases.

<Developer 18 (pH: 7.0)>
・ Water Amount of 10,000 parts combined with other ingredients ・ Ethylene glycol mono-n-hexyl ether Amounts listed in Tables 1 to 4 ・ Softazoline LPB-R
(Amphoteric surfactant manufactured by Kawaken Fine Chemicals Co., Ltd.) 500 parts Developer 18 was a single phase but increased in viscosity.

<Developer 19 (pH: 7.0)>
・ Water: 10,000 parts combined with other ingredients ・ 1,000 parts of benzyl alcohol ・ Perex NBL (anionic surfactant manufactured by Kao Corporation) 500 parts

<Developer 20 (pH: 7.0)>
・ Water Amount of 10,000 parts combined with other components ・ Ethylene glycol mono-n-hexyl ether Amount described in Tables 1 to 4 ・ Nonionic surfactant shown in Exemplified Compound B-14 Tables 1 to 4 Perex NBL (anionic surfactant manufactured by Kao Corporation) 500 parts

<Developer 21 (pH: 9.8)>
・ Water 7289.8 parts ・ Sodium carbonate 130 parts ・ Sodium bicarbonate 70 parts ・ New Coal B-13
(Nippon Emulsifier Co., Ltd. Nonionic Surfactant) 500 parts ・ Acacia 250 parts ・ Hydroxyalkylated starch (manufactured by Nissho Chemical Co., Ltd .: Penon JE66) 700 parts ・ Primary ammonium phosphate 20 parts ・ 2-Bromo- 2-nitropropane-1,3-diol 0.1 part, 2-methyl-4-isothiazolin-3-one 0.1 part, ethylene glycol mono-n-hexyl ether 500 parts

<Developers in Tables 1 to 4>
SP-200: benzyl alcohol-containing developer manufactured by KODAK

(Examples 125-161 and Comparative Examples 31-40)
<Preparation of lithographic printing plate precursor (4)>
The photosensitive layer coating solution (1) in the preparation of the lithographic printing plate precursor (1) is changed to the photosensitive layer coating solution (4) having the following composition, and the protective layer coating solution (1) is changed to the protective layer coating solution (3). A lithographic printing plate precursor (4) was obtained in the same manner as in the production of the lithographic printing plate precursor (1) except for the above.

[Photosensitive layer coating solution (4)]
-0.18 parts of the following polymerization initiator (1)-0.04 parts of the following sensitizing dye (1) (absorption maximum wavelength; 359 nm)-0.54 parts as the solid content of the binder polymer described in Table 3-polymerizable compound (Aronix M-315, manufactured by Toagosei Co., Ltd.)) 0.45 part, leuco crystal violet 0.20 part, thermal polymerization inhibitor 0.01 part (N-nitrosophenylhydroxylamine aluminum salt)
・ Pionine A-20 (manufactured by Takemoto Yushi Co., Ltd.) 0.05 parts ・ Fluorosurfactant (1) 0.001 part ・ Methyl ethyl ketone 3.50 parts ・ 1-methoxy-2-propanol 8.00 parts

<Exposure>
The lithographic printing plate precursor (4) was image-exposed with a Violet semiconductor laser plate setter Vx9600 manufactured by Fujifilm Electronic Imaging (FFEI) (equipped with an InGaN-based semiconductor laser (emission wavelength 405 nm ± 10 nm / output 30 mW)). Image drawing was performed at a resolution of 2,438 dpi using an FM screen (TAFFETA 20) manufactured by FUJIFILM Corporation with a plate surface exposure of 0.05 mJ / cm ² .
The exposure image includes the solid image and the fine line image.

<Development processing and evaluation>
In Examples 125 to 161 and Comparative Examples 31 to 40 except for Example 157, the development processing and evaluation shown in Table 9 were performed in the same manner as in Examples 1 to 124 except for Examples 33, 50, 87, and 124. It was. For Example 157, the development treatment and evaluation shown in Table 9 were performed in the same manner as in Examples 33, 50, 87, and 124.
As a result, the results shown in Table 10 were obtained.
From the results of Table 10, in any of Examples 125 to 161 using the method for preparing a lithographic printing plate of the present invention, the odor of the developer, the developability, and the development sludge due to the development removal component are good, and the sensitivity It can be seen that a lithographic printing plate excellent in printing durability can be obtained.

DESCRIPTION OF SYMBOLS 1 Automatic developing device 10 Development processing part 12 Printing plate precursor 14 Developing part 16 Washing part 18 Desensitizing part 20 Drying part 24 Developing tank 61 Rotating brush roll 62 Receiving roll 63 Conveying roll 64 Conveying guide plate 65 Spray pipe 66 Pipe line 67 Filter 68 Plate supply table 69 Discharge table 70 Developer tank 71 Circulation pump 72 Plates 141 and 142 Brush roll (rubbing member)
200 Pre-processing section

Claims (21)

Producing a negative planographic printing plate precursor having a photopolymerizable photosensitive layer on a support,
A step of imagewise exposing the negative lithographic printing plate precursor,
The negative lithographic printing plate exposed to a developer containing at least (Component A) a compound represented by the following formula (I), (Component B) a compound represented by the following formula (II), and (Component C) water. Including the step of developing the original plate,
A method for making a lithographic printing plate, wherein the photopolymerizable photosensitive layer is sensitive to infrared light, does not contain a borate salt, and contains a cyanine dye and an iodonium salt.

(In the formula, R ¹ represents a linear or branched alkyl group having 4 to 8 carbon atoms, R ² and R ³ each independently represents a hydrogen atom or a methyl group, and any one of R ² and R ³ When one is a methyl group, the other is a hydrogen atom, n represents 1 or 2, R ⁴ represents a substituted or unsubstituted phenyl group, 1-naphthyl group or 2-naphthyl group, and m is 4 to 20 Represents an integer.) Producing a negative planographic printing plate precursor having a photopolymerizable photosensitive layer on a support,
A step of imagewise exposing the negative lithographic printing plate precursor,
The negative lithographic printing plate exposed to a developer containing at least (Component A) a compound represented by the following formula (I), (Component B) a compound represented by the following formula (II), and (Component C) water. Including the step of developing the original plate,
The plate making method of a lithographic printing plate, wherein the photopolymerizable photosensitive layer contains a urethane-acrylic hybrid polymer.

(In the formula, R ¹ represents a linear or branched alkyl group having 4 to 8 carbon atoms, R ² and R ³ each independently represents a hydrogen atom or a methyl group, and any one of R ² and R ³ When one is a methyl group, the other is a hydrogen atom, n represents 1 or 2, R ⁴ represents a substituted or unsubstituted phenyl group, 1-naphthyl group or 2-naphthyl group, and m is 4 to 20 Represents an integer.) Producing a negative planographic printing plate precursor having a photopolymerizable photosensitive layer on a support,
A step of imagewise exposing the negative lithographic printing plate precursor,
The negative lithographic printing plate exposed to a developer containing at least (Component A) a compound represented by the following formula (I), (Component B) a compound represented by the following formula (II), and (Component C) water. Including the step of developing the original plate,
The plate making method of a lithographic printing plate, wherein the photopolymerizable photosensitive layer contains an acrylic polymer having a monomer unit derived from a vinyl carbazole compound.

(In the formula, R ¹ represents a linear or branched alkyl group having 4 to 8 carbon atoms, R ² and R ³ each independently represents a hydrogen atom or a methyl group, and any one of R ² and R ³ When one is a methyl group, the other is a hydrogen atom, n represents 1 or 2, R ⁴ represents a substituted or unsubstituted phenyl group, 1-naphthyl group or 2-naphthyl group, and m is 4 to 20 Represents an integer.)   The plate making method of a lithographic printing plate according to any one of claims 1 to 3, wherein n is 1. The plate making method of a lithographic printing plate according to any one of claims 1 to 4, wherein R ² and R ³ are both hydrogen atoms. The lithographic printing plate making method according to any one of Claims 1 to 5, wherein R ¹ is an n-butyl group, an n-hexyl group, or a 2-ethylhexyl group.   The lithographic printing plate making method according to any one of claims 1 to 6, wherein Component A is a compound having an octanol / water partition coefficient of 0.8 to 2.0.   The component A is a compound selected from the group consisting of ethylene glycol mono n-butyl ether, ethylene glycol mono n-hexyl ether, and propylene glycol mono n-butyl ether. Plate making method of lithographic printing plate.   The plate making method of a lithographic printing plate according to any one of Claims 1 to 8, wherein the content of Component A in the developer exceeds 40% by weight and exceeds the solubility of Component A in water.   The plate-making method of the lithographic printing plate as described in any one of Claims 1-8 whose content of the component A in the said developing solution is 2 to 30 weight%.   The lithographic printing plate making method according to claim 10, wherein the content of component A in the developer is 5 to 20% by weight. The plate making method of a lithographic printing plate according to any one of claims 1 to 11, wherein R ⁴ is a substituted or unsubstituted 1-naphthyl group or 2-naphthyl group.   The lithographic printing plate making method according to any one of claims 1 to 12, wherein the m is 9 to 16.   The plate making method of a lithographic printing plate according to any one of Claims 1 to 13, wherein the content of Component B in the developer is not less than 20% by weight and not more than an amount capable of solubilizing Component A.   The plate-making method of the lithographic printing plate as described in any one of Claims 1-13 whose content of the component B in the said developing solution is 1 to 15 weight%.   The lithographic printing plate making method according to claim 15, wherein the content of component B in the developer is 4 to 10% by weight.   The lithographic printing plate making method according to any one of Claims 1 to 16, wherein the content of Component C in the developer is 50% by weight or more.   The lithographic printing plate making method according to any one of claims 1 to 17, wherein the developer further contains an anionic surfactant or an amphoteric surfactant.   The lithographic printing plate making method according to any one of claims 1 to 18, wherein the developer has a pH of 6 to 8.   The lithographic printing plate making method according to claim 3, wherein the acrylic polymer further contains a monomer unit derived from acrylonitrile.   The lithographic printing plate of claim 2, wherein the urethane-acrylic hybrid polymer has monomer units derived from a compound selected from the group consisting of diphenylmethane diisocyanate, m-tolylene diisocyanate, isophorone diisocyanate, and dicyclohexylmethane diisocyanate. Plate making method.

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