JP2002365790A - Original plate of planographic printing plate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an original plate of a planographic printing plate having improved printing stain resistance, giving a large number of prints free of stain even under ever printing conditions, capable of plate making by scanning exposure according to a digital signal and excellent in on-machine developability. SOLUTION: The original plate has a hydrophilic layer containing a hydrophilic high molecular compound of formula (I) on a support and contains a compound capable of forming surface-hydrophobed regions when heated or irradiated with radiant rays, e.g. heat meltable hydrophobic fine particles in the hydrophilic layer. In the formula (I), R<1> -R<4> are each H or a 1-8C hydrocarbon group; (m) is 0, 1 or 2; (n) is an integer of 1-8; L is a single bond or an organic linking group; and Y is -CONH2 or the like.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a novel lithographic printing plate precursor. More specifically, the present invention relates to a lithographic printing plate precursor capable of scanning and exposing an image with a laser beam based on a digital signal and having excellent sensitivity and stain resistance. Regarding the printing plate.

[0002]

2. Description of the Related Art Lithographic printing is a printing method utilizing a plate material having an oleophilic area for receiving ink and an ink-repellent area (hydrophilic area) for receiving dampening water without receiving ink. In this case, a photosensitive lithographic printing plate precursor (PS plate) is widely used. As the PS plate, a plate provided with a photosensitive layer on a support such as an aluminum plate has been put to practical use and widely used. In such a PS plate, the photosensitive layer in the non-image area is removed by image exposure and development, and printing is performed using the hydrophilicity of the substrate surface and the lipophilicity of the photosensitive layer in the image area.
In such a plate material, high hydrophilicity is required on the substrate surface in order to prevent contamination of the non-image portion.

Conventionally, as a hydrophilic substrate or a hydrophilic layer used for a lithographic printing plate, an anodized aluminum substrate,
Alternatively, silicate treatment is generally performed on the anodized aluminum substrate to further increase the hydrophilicity. Further, studies on a hydrophilic substrate or a hydrophilic layer using these aluminum supports have been actively conducted. For example, Japanese Patent Application Laid-Open No. 7-1853 discloses a substrate treated with a primer with polyvinyl phosphonic acid. JP-A-59-101651 describes a technique using a polymer having a sulfonic acid group as an undercoat layer of a photosensitive layer.
A technique using polyvinyl benzoic acid or the like as a primer is also proposed.

On the other hand, a hydrophilic layer when a flexible support such as PET (polyethylene phthalate) or cellulose acetate is used without using a metal support such as aluminum is described in JP-A-8-292558. A swelling hydrophilic layer comprising a hydrophilic polymer and a hydrophobic polymer, a PET support having a microporous hydrophilic crosslinked silicate surface described in EP 0709228, and described in JP-A-8-27287 and JP-A-8-507727. Various techniques have been proposed, such as a hydrophilic layer containing a hydrophilic polymer and cured with a hydrolyzed tetraalkyl orthosilicate.

[0005] These hydrophilic layers provide a lithographic printing plate which has improved hydrophilicity compared to conventional ones and gives a printed matter free from stains at the start of printing. However, even under more severe printing conditions, the hydrophilic layer does not peel off from the support or the hydrophilicity of the surface does not decrease, and a large number of stain-free prints can be obtained. A lithographic printing plate precursor was desired. At the present time, further improvement in hydrophilicity is required from a practical viewpoint.

[0006] On the other hand, many studies have been made on printing plates for computer-to-plate systems, which have made remarkable progress in recent years. Among them, with the aim of further streamlining the process and solving the problem of waste liquid treatment, development-free lithographic printing plate precursors that can be mounted on a printing machine and printed without being developed after exposure have been studied. A method has been proposed. One of the methods to eliminate the processing step is to remove the non-image area of the printing plate by mounting the exposed printing plate on the cylinder of the printing press and supplying fountain solution and ink while rotating the cylinder. There is a method called on-press development. That is, the printing master is mounted on a printing machine as it is after exposure, and the process is completed in a normal printing process.

A lithographic printing plate precursor suitable for such on-press development has a photosensitive layer that is soluble in fountain solution and ink solvent, and is developed on a printing machine placed in a bright room. It is required to have a light room handling property suitable for the environment. As a printing plate which does not require a developing step, WO94 / 23954 describes a non-processing printing plate which is provided with a crosslinked hydrophilic layer on a substrate and contains a microencapsulated hot-melt substance therein. In this plate, the microcapsules collapse by the action of heat generated in the laser exposure area, the lipophilic substance in the capsules melts out, and the surface of the hydrophilic layer becomes hydrophobic. This printing plate precursor does not require development processing, but the hydrophilicity and durability of the hydrophilic layer provided on the substrate are insufficient, and there is a problem that the non-image area gradually becomes dirty as the printing is performed. there were.

[0008]

SUMMARY OF THE INVENTION An object of the present invention to solve the above-mentioned conventional problems is to provide a hydrophilic layer having high hydrophilicity and excellent durability. It is an object of the present invention to provide a positive or negative type lithographic printing plate precursor capable of improving the performance and obtaining a large number of prints free of stain even under severe printing conditions. A further object of the present invention is to make plate making by scanning exposure based on a digital signal, and to make a plate by a simple water developing operation after image formation, or to perform printing without any special developing process. It is an object of the present invention to provide a lithographic printing plate precursor that can be mounted on and printed.

[0009]

Means for Solving the Problems The present inventors have studied to achieve the above object, and as a result, have found that a hydrophilic layer having a crosslinked structure formed of an organic-inorganic composite containing a specific hydrophilic polymer is formed. It has been found that the problem can be solved by adding a compound capable of forming a surface hydrophobized region to the present invention, and the present invention has been completed.

That is, the lithographic printing plate precursor according to the present invention has a hydrophilic graft chain on a support, and contains Si, T
a hydrophilic layer having a crosslinked structure formed by hydrolysis and polycondensation of a metal alkoxide selected from i, Zr, and Al; and a compound capable of forming a surface-hydrophobic region in the hydrophilic layer. It is characterized by. A hydrophilic layer having such a hydrophilic graft chain and having a cross-linked structure formed by hydrolysis and condensation polymerization of a metal alkoxide selected from Si, Ti, Zr, and Al is preferably a compound represented by the following general formula: It contains a hydrophilic polymer compound represented by (I).

[0011]

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In the formula (I), R ¹ , R ² , R ³ and R ⁴ each independently represent a hydrogen atom or a hydrocarbon group having 1 to 8 carbon atoms, m represents 0, 1 or 2; Represents an integer of 1 to 8. L represents a single bond or an organic linking group, and Y is -NHC
_{^{OR 5, -CONH 2, -CON (}} R 5) 2, -COR 5,
—OH, —CO ₂ M or —SO ₃ M, wherein R ⁵
Represents an alkyl group having 1 to 8 carbon atoms, and M represents a hydrogen atom, an alkali metal, an alkaline earth metal or onium. The hydrophilic layer according to the present invention is preferably a hydrophilic polymer compound represented by the general formula (I), and further preferably a compound represented by the following general formula (I)
It can be formed by preparing a hydrophilic coating solution composition containing the crosslinking component represented by I), applying the composition to the surface of a support, and drying.

[0013]

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In the formula (II), R ⁶ and R ⁷ each independently represent an alkyl group or an aryl group, and X represents Si, Al, T
i represents Zr, and m represents an integer of 0 to 2.

Although the function of the present invention is not clear, it has a hydrophilic graft chain on a support, and has a Si, Ti, Z
r, hydrolysis of a metal alkoxide selected from Al,
The hydrophilic layer having a crosslinked structure formed by condensation polymerization,
Hydrophilic functional groups introduced in the state of graft chains are unevenly distributed on the surface in a free state, and an organic-inorganic composite film having a high-density crosslinked structure is formed by hydrolysis and condensation polymerization of metal alkoxide. Therefore, a high-strength film having high hydrophilicity is obtained. Specifically, when a hydrophilic coating solution composition containing the hydrophilic polymer compound represented by the general formula (I) is prepared and applied to form a hydrophilic layer, the hydrophilic polymer compound Has a cross-linked structure formed by Si (OR) ₄ due to the interaction between the silane coupling groups, so that high printing durability can be realized by the strong cross-linked structure and the hydrophilic group of the hydrophilic polymer compound Is located at the other end of the linear stem,
It is presumed that the mobility is high, the supply / drainage speed of the dampening solution supplied at the time of printing is high, and the high hydrophilicity effectively suppresses stains on the non-image portion, thereby enabling high-quality image formation. . Further, by adding the crosslinking component represented by the general formula (II) to the hydrophilic coating liquid composition, the interaction between the silane coupling group and the crosslinking component forms a crosslinked structure with higher density, High printing durability is expected by further improving the film strength.

Further, in the present invention, a compound capable of forming a surface-hydrophobic region is contained in the hydrophilic layer, so that the surface of the heat-fusible hydrophobic particles or the like can be contained in a matrix composed of a hydrophilic polymer compound. The compound capable of forming the hydrophobic region is heated, or fused to each other in the radiation irradiation region to form a hydrophobic region, and it is possible to form an image by scanning exposure with laser light or the like in a short time, and as an image forming layer Function. In addition, since the non-image area retains excellent hydrophilicity due to the hydrophilic layer having high film strength, plate making by a simple water development processing operation, or mounting directly to a printing machine without the need for development processing is required. This makes it possible to develop high on-press developability of plate making.

[0017]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The lithographic printing plate precursor according to the present invention will be described in detail below. The lithographic printing plate precursor according to the invention has a hydrophilic layer having a specific hydrophilic polymer and a crosslinked structure composed of an organic-inorganic composite on a support, and the hydrophilic layer has a heat-melting property. It has a structure containing a compound capable of forming a surface hydrophobic region such as hydrophobic particles, and the hydrophilic layer itself has an image forming function. Hereinafter, each configuration of the lithographic printing plate precursor according to the invention will be described in detail.

[Hydrophilic layer] The hydrophilic layer in the present invention comprises:
Having a hydrophilic graft chain, and Si, Ti, Zr, A
l has a cross-linked structure formed by hydrolysis and condensation polymerization of a metal alkoxide selected from the group consisting of a hydrophilic layer having such a cross-linked structure. It can be appropriately formed using a compound having a hydrophilic functional group capable of forming a graft chain. Among the metal alkoxides, alkoxides of Si are preferable in terms of reactivity and availability,
Specifically, a compound used for a silane coupling agent can be suitably used.

In the present invention, the crosslinked structure formed by hydrolysis and polycondensation of a metal alkoxide as described above is hereinafter referred to as a sol-gel crosslinked structure as appropriate. The hydrophilic layer having such a free hydrophilic graft chain and a sol-gel crosslinked structure preferably contains a hydrophilic polymer described in detail below. Hereinafter, the components and the method for forming the hydrophilic layer in a preferred embodiment of the hydrophilic layer according to the present invention will be described in detail.

(1. Polymer compound represented by general formula (I)) The polymer compound represented by general formula (I) is a hydrophilic polymer having a silane coupling group at a terminal. It is appropriately referred to as a specific hydrophilic polymer. In the general formula (I), R ¹ , R ² , R ³ and R ⁴ each independently represent a hydrogen atom or a hydrocarbon group having 8 or less carbon atoms. Examples of the hydrocarbon group include an alkyl group and an aryl group, and a linear, branched or cyclic alkyl group having 8 or less carbon atoms is preferable. Specifically, a methyl group, an ethyl group,
Propyl, butyl, pentyl, hexyl, heptyl, octyl, isopropyl, isobutyl,
s-butyl group, t-butyl group, isopentyl group, neopentyl group, 1-methylbutyl group, isohexyl group, 2-
Examples include an ethylhexyl group, a 2-methylhexyl group, and a cyclopentyl group. R ¹ , R ² , R ³ and R ⁴ are preferably a hydrogen atom, a methyl group or an ethyl group from the viewpoint of effects and availability.

These hydrocarbon groups may further have a substituent. When the alkyl group has a substituent, the substituted alkyl group is constituted by a bond between the substituent and an alkylene group, and a monovalent nonmetallic atomic group other than hydrogen is used as the substituent. Preferred examples include a halogen atom (-F, -Br, -Cl, -I), a hydroxyl group, an alkoxy group, an aryloxy group, a mercapto group, an alkylthio group, an arylthio group, an alkyldithio group, an aryldithio group, an amino group, N-alkylamino group, N, N-
Diarylamino group, N-alkyl-N-arylamino group, acyloxy group, carbamoyloxy group, Ν-alkylcarbamoyloxy group, N-arylcarbamoyloxy group, N, N-dialkylcarbamoyloxy group, N, N-diarylcarbamoyl An oxy group, an N-alkyl-N-arylcarbamoyloxy group, an alkylsulfoxy group, an arylsulfoxy group, an acylthio group,
Acylamino group, N-alkylacylamino group, N-arylacylamino group, ureido group, N′-alkylureido group, N ′, N′-dialkylureido group, N′-
Arylureido group, N ′, N′-diarylureido group, N′-alkyl-N′-arylureido group, N-
Alkyl ureido group,

N-aryl ureido, N'-alkyl-N-alkyl ureido, N'-alkyl-N-aryl ureido, N ', N'-dialkyl-N-alkyl ureate, N', N '-Dialkyl-N-arylureido group, N'-aryl -−- alkylureido group, N'-aryl-N-arylureido group, N',
An N′-diaryl-N-alkylureido group, N ′,
An N′-diaryl-N-arylureido group, an N′-alkyl-N′-aryl-N-alkylureido group,
N′-alkyl-N′-aryl-N-arylureido group, alkoxycarbonylamino group, aryloxycarbonylamino group, N-alkyl-N-alkoxycarbonylamino group, N-alkyl-N-aryloxycarbonylamino group, N-aryl-N-alkoxycarbonylamino group, N-aryl-N-aryloxycarbonylamino group, formyl group, acyl group, carboxyl group,

Alkoxycarbonyl group, aryloxycarbonyl group, carbamoyl group, N-alkylcarbamoyl group, N, N-dialkylcarbamoyl group, N-arylcarbamoyl group, N, N-diarylcarbamoyl group, N-alkyl-N-aryl Rucarbamoyl, alkylsulfinyl, arylsulfinyl, alkylsulfonyl, arylsulfonyl, sulfo (-
SO ₃ H) and its conjugate base group (hereinafter, referred to as sulfonato group), alkoxysulfonyl group, aryloxysulfonyl group, sulfinamoyl group, N-alkylsulfinamoyl group, N, N-dialkylsulfinamoyl group, N
-Arylsulfinamoyl group, N, N-diarylsulfinamoyl group, N-alkyl-N-arylsulfinamoyl group, sulfamoyl group, N-alkylsulfamoyl group, N, N-dialkylsulfamoyl group, N
- arylsulfamoyl group, N, N- diaryl sulfamoyl group, N- alkyl -N- arylsulfamoyl group phosphono group (-PO ₃ H ₂₎ and its conjugated base group (hereinafter referred to as phosphonato group) , dialkyl phosphono group _{(-PO 3 (alkyl) 2)} , diaryl phosphono group _{(-PO 3 (aryl) 2)} , alkyl aryl phosphono group _{(-PO 3 (alkyl) (aryl} )), monoalkyl phosphono Group (—PO ₃ H (alkyl))
And its conjugated base group (hereinafter referred to as alkylphosphonate group), monoarylphosphono group (-PO ₃ H (ar
yl)) and a conjugated base group (hereinafter referred to as aryl phosphonophenyl group), phosphonooxy group (-OPO ₃ H ₂₎
And its conjugated base group (hereinafter, referred to as a phosphonatoxy group), a dialkylphosphonooxy group (—OPO ₃ (a
lkyl) ₂ ), a diarylphosphonooxy group (—O
PO ₃ (aryl) ₂ ), an alkylarylphosphonooxy group (—OPO (alkyl) (aryl)), a monoalkylphosphonooxy group (—OPO ₃ H (alky)
1)) and its conjugate base group (hereinafter referred to as alkylphosphonatooxy group), monoarylphosphonooxy group (-OPO ₃ H (aryl)) and its conjugate base group (hereinafter referred to as arylphosphonatooxy group). ), A morpholino group, a cyano group, a nitro group, an aryl group, an alkenyl group, and an alkynyl group.

In these substituents, specific examples of the alkyl group include the aforementioned alkyl groups, and specific examples of the aryl group include phenyl, biphenyl, naphthyl, tolyl2, xylyl, mesityl. Group, cumenyl group, chlorophenyl group, bromophenyl group, chloromethylphenyl group, hydroxyphenyl group, methoxyphenyl group, ethoxyphenyl group, phenoxyphenyl group,
Acetoxyphenyl, benzyloxyphenyl, methylthiophenyl, phenylthiophenyl, methylaminophenyl, dimethylaminophenyl, acetylaminophenyl, carboxyphenyl, methoxycarbonylphenyl, ethoxyphenylcarbonyl, phenoxycarbonyl Examples include a phenyl group, an N-phenylcarbamoylphenyl group, a phenyl group, a cyanophenyl group, a sulfophenyl group, a sulfonatophenyl group, a phosphonophenyl group, and a phosphonatophenyl group. Examples of the alkenyl group include a vinyl group, a 1-propenyl group, a 1-butenyl group, a cinnamyl group, and a 2-chloro-1-ethenyl group. Examples of the alkynyl group include an ethynyl group, Propynyl group,
Examples thereof include a 1-butynyl group and a trimethylsilylethynyl group. Examples of G ¹ in the acyl group (G ¹ CO-),
Examples include hydrogen, and the above-described alkyl and aryl groups.

Of these substituents, more preferred are a halogen atom (-F, -Br, -Cl, -I),
An alkoxy group, an aryloxy group, an alkylthio group, an arylthio group, an N-alkylamino group, an N, N-dialkylamino group, an acyloxy group, an N-alkylcarbamoyloxy group, an N-arylcabamoyloxy group, an acylamino group, a formyl group, Acyl, carboxyl, alkoxycarbonyl, aryloxycarbonyl, carbamoyl, N-alkylcarbamoyl, N, N-
Dialkylcarbamoyl group, N-arylcarbamoyl group, N-alkyl-N-arylcarbamoyl group, sulfo group, sulfonato group, sulfamoyl group, N-alkylsulfamoyl group, N, N-dialkylsulfamoyl group, N-aryl Sulfamoyl group, N-alkyl-N
An arylsulfamoyl group, a phosphono group, a phosphonate group, a dialkylphosphono group, a diarylphosphono group, a monoalkylphosphono group, an alkylphosphonato group, a monoarylphosphono group, an arylphosphonato group, a phosphonooxy group, Examples include a phosphonatoxy group, an aryl group, and an alkenyl group.

On the other hand, the alkylene group in the substituted alkyl group may be a divalent organic residue obtained by removing any one of the above hydrogen atoms on the alkyl group having 1 to 20 carbon atoms. Preferably, examples thereof include a linear alkylene group having 1 to 12 carbon atoms, a branched alkylene group having 3 to 12 carbon atoms and a cyclic alkylene group having 5 to 10 carbon atoms. Preferred specific examples of the substituted alkyl group obtained by combining the substituent with an alkylene group include chloromethyl group, bromomethyl group, 2-chloroethyl group, trifluoromethyl group, methoxymethyl group, methoxyethoxyethyl group, and allyl. Oxymethyl group, phenoxymethyl group, methylthiomethyl, tolylthiomethyl group, ethylaminoethyl group, diethylaminopropyl group, morpholinopropyl group, acetyloxymethyl group, benzoyloxymethyl group, N-cyclohexylcarbamoyloxyethyl group, N- Phenylcarbamoyloxyethyl group, acetylaminoethyl group, N-methylbenzoylaminopropyl group, 2-oxyethyl group, 2-oxypropyl group, carboxypropyl group, methoxycarbonylethyl group, allyloxy Carbonyl butyl group,

Chlorophenoxycarbonylmethyl, carbamoylmethyl, N-methylcarbamoylethyl, N, N-dipropylcarbamoylmethyl, N-
(Methoxyphenyl) carbamoylethyl group, N-methyl-N- (sulfophenyl) carbamoylmethyl group,
Sulfobutyl group, sulfonatobutyl group, sulfamoylbutyl group, N-ethylsulfamoylmethyl group, N, N
-Dipropylsulfamoylpropyl group, N-tolylsulfamoylpropyl group, N-methyl-N- (phosphonophenyl) sulfamoyloctyl group, phosphonobutyl group, phosphonatohexyl group, diethylphosphonobutyl group, Diphenylphosphonopropyl group, methylphosphonobutyl group, methylphosphonatobutyl group, tolylphosphonohexyl group, tolylphosphonatohexyl group, phosphonooxypropyl group, phosphonatoxybutyl group, benzyl group, phenethyl group, α-methyl Benzyl group, 1-methyl-1-phenylethyl group, p-methylbenzyl group, cinnamyl group, allyl group, 1-propenylmethyl group, 2-butenyl group, 2-methylallyl group, 2
-Methylpropenylmethyl group, 2-propynyl group, 2-
Butynyl group, 3-butynyl group and the like.

L represents a single bond or an organic linking group. Here, when L represents an organic linking group, L represents a polyvalent linking group comprising a non-metallic atom, specifically, 1 to 60 carbon atoms and 0 to 10 nitrogen atoms. Atoms, from 0 to 50 oxygen atoms, from 1 to 100 hydrogen atoms, and from 0 to 20 sulfur atoms. More specific examples of the linking group include the following structural units or those formed by combining them.

[0029]

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Further, Y is -NHCOR ⁵ , -CONH ₂ ,
—CON (R ⁵ ) ₂ , —COR ⁵ , —OH, —CO ₂ M or —SO ₃ M, wherein R ⁵ represents a linear, branched or cyclic alkyl group having 1 to 8 carbon atoms. Represent. Also, -CON
When the compound has a plurality of R ⁵ such as (R ⁵ ) ₂ , R ⁵ may be bonded to each other to form a ring, and the formed ring may be a hetero atom such as an oxygen atom, a sulfur atom, or a nitrogen atom. It may be a heterocycle containing atoms. R ⁵ may further have a substituent. Examples of the substituent that can be introduced here include the aforementioned R 5
^{In the case where 1} , R ² , R ³ and R ⁴ are alkyl groups, the same substituents as those which can be introduced can also be used.

Specific examples of R ⁵ include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, an isopropyl group, an isobutyl group, an s-butyl group and a t-butyl group. Butyl group, isopentyl group, neopentyl group, 1-methylbutyl group, isohexyl group, 2-ethylhexyl group, 2-methylhexyl group,
Preferable examples include a cyclopentyl group. Examples of M include a hydrogen atom; an alkali metal such as lithium, sodium and potassium; an alkaline earth metal such as calcium and barium; and an onium such as ammonium, iodonium and sulfonium. The Y, _{specifically, -NHCOCH 3, -CONH 2, -COOH} , -S
O ₃ ^- NMe ₄ ^+, a morpholino group, etc. are preferable.

Specific examples of the specific hydrophilic polymer (exemplary compound 1 to exemplary compound 12) which can be suitably used in the present invention are shown below, but the present invention is not limited thereto.

[0033]

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The specific hydrophilic polymer according to the present invention comprises a radically polymerizable monomer represented by the following general formula (i) and a silane cup having a chain transfer ability in radical polymerization represented by the following general formula (ii). It can be synthesized by radical polymerization using a ring agent. Since the silane coupling agent (ii) has a chain transfer ability,
In the radical polymerization, a polymer having a silane coupling group introduced into the terminal of the polymer main chain can be synthesized.

[0035]

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In the above formulas (i) and (ii), R ¹
To R ⁴ , L, Y, n and m are as defined in the above formula (I). These compounds are commercially available and can be easily synthesized.

As a radical polymerization method for synthesizing the hydrophilic polymer represented by the general formula (I), any of conventionally known methods can be used. Specifically, general radical polymerization methods include, for example, New Polymer Experimental Science 3, Polymer Synthesis and Reaction 1 (edited by the Society of Polymer Science, Kyoritsu Shuppan), New Experimental Chemistry Course 19, Polymer Chemistry (I) (Edited by The Chemical Society of Japan, Maruzen), Materials Engineering Course, Synthetic Polymer Chemistry (Tokyo Denki University Press), etc., and these can be applied.

(2. Crosslinking component represented by general formula (II))
The cross-linking component represented by the general formula (II) used herein is a compound having a polymerizable functional group in its structure and performing a function as a cross-linking agent, and condensation polymerization with the specific hydrophilic polymer. By doing so, a strong film having a crosslinked structure is formed. In the general formula (II), R ⁶ represents a hydrogen atom, an alkyl group or an aryl group, R ⁷ represents an alkyl group or an aryl group, X represents Si, Al, Ti or Zr;
m represents an integer of 0 to 2. When R ⁶ and R ⁷ represent an alkyl group, the number of carbon atoms is preferably 1 to 4. The alkyl group or the aryl group may have a substituent, and examples of the substituent that can be introduced include a halogen atom, an amino group, and a mercapto group. This compound is a low molecular compound, and preferably has a molecular weight of 1,000 or less.

The following are specific examples of the crosslinking component represented by the general formula (II), but the present invention is not limited thereto. When X is Si, that is, when the hydrolyzable compound contains silicon, for example, trimethoxysilane, triethoxysilane, tripropoxysilane, tetramethoxysilane, tetraethoxysilane, tetrapropoxysilane, methyltrimethoxysilane Silane, ethyltriethoxysilane, propyltrimethoxysilane, methyltriethoxysilane, ethyltriethoxysilane, propyltriethoxysilane, dimethyldimethoxysilane,
Diethyldiethoxysilane, γ-chloropropyltriethoxysilane, γ-mercaptopropyltrimethoxysilane, γ-mercaptopropyltriethoxysilane, γ
-Aminopropyltriethoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, phenyltripropoxysilane, diphenyldimethoxysilane,
Diphenyldiethoxysilane and the like can be mentioned.
Of these, particularly preferred are tetramethoxysilane, tetraethoxysilane, methyltolumethoxysilane, ethyltrimethoxysilane, methyltriethoxysilane, ethyltriethoxysilane, dimethyldiethoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane. Examples include silane, diphenyldimethoxysilane, diphenyldiethoxysilane, and the like.

When X is Al, that is, when the hydrolyzable compound contains aluminum, for example, trimethoxyaluminate, triethoxyaluminate, tripropoxyaluminate, tetraethoxyaluminate, etc. Can be mentioned. When X is Ti, that is, as a compound containing titanium, for example, trimethoxy titanate, tetramethoxy titanate, triethoxy titanate, tetraethoxy titanate, tetrapropoxy titanate, chlorotrimethoxy titanate, chlorotriethoxy titanate, ethyl trititanate Examples include methoxy titanate, methyl triethoxy titanate, ethyl triethoxy titanate, diethyl diethoxy titanate, phenyl trimethoxy titanate, phenyl triethoxy titanate, and the like. When X is Zr, that is, when the compound contains zirconium, for example, zirconate corresponding to the compound exemplified as the compound containing titanium can be used.

(3. Formation of Hydrophilic Layer) In the present invention, the hydrophilic layer is prepared by preparing a hydrophilic coating solution composition containing the specific hydrophilic polymer, coating the composition on a suitable support, It can be formed by drying. In preparing the hydrophilic coating liquid composition, the content of the specific hydrophilic polymer is preferably 10% by weight or more and less than 50% by weight in terms of solid content. When the content is 50% by weight or more, the film strength tends to decrease, and when the content is less than 10% by weight, the film properties are reduced, and the possibility of cracks in the film is increased. Absent.

When the crosslinking component is added to the hydrophilic coating solution composition in a preferred embodiment, the amount of the crosslinking component is preferably 5 mol% or more based on the silane coupling group in the specific hydrophilic polymer. Further, the amount is preferably 10 mol% or more. The upper limit of the amount of the cross-linking component is not particularly limited as long as it is within a range capable of sufficiently cross-linking with the hydrophilic polymer. However, when added in a large excess, a problem such as stickiness of the produced hydrophilic surface due to the cross-linking component not involved in cross-linking occurs. there is a possibility.

A specific hydrophilic polymer having a silane coupling group at a terminal, preferably a cross-linking component, is dissolved in a solvent and stirred well, whereby these components are hydrolyzed and polycondensed. The organic-inorganic composite sol solution becomes the hydrophilic coating solution according to the present invention, whereby a surface hydrophilic layer having high hydrophilicity and high film strength is formed. In the preparation of the organic-inorganic composite sol liquid, it is preferable to use an acidic catalyst or a basic catalyst in combination in order to promote hydrolysis and polycondensation reaction, and in order to obtain a practically preferable reaction efficiency, the catalyst is indispensable. It is.

As the catalyst, an acid or a basic compound may be used as it is, or a catalyst dissolved in a solvent such as water or alcohol (hereinafter referred to as an acidic catalyst or a basic catalyst, respectively). The concentration at the time of dissolution in the solvent is not particularly limited, and may be appropriately selected depending on the characteristics of the acid or basic compound to be used, the desired content of the catalyst, and the like. The condensation rate tends to be faster. However, when a basic catalyst having a high concentration is used, a precipitate may be formed in a sol solution. Therefore, when a basic catalyst is used, its concentration is desirably 1 N or less in terms of a concentration in an aqueous solution.

The type of the acidic catalyst or the basic catalyst is not particularly limited, but when it is necessary to use a catalyst having a high concentration, a catalyst composed of an element which hardly remains in the coating film after drying is preferable. Specifically, acidic catalysts are represented by hydrogen halides such as hydrochloric acid, nitric acid, sulfuric acid, sulfurous acid, hydrogen sulfide, perchloric acid, hydrogen peroxide, carbonic acid, carboxylic acids such as formic acid and acetic acid, and their RCOOH. Substituted carboxylic acids in which R in the structural formula is substituted with other elements or substituents, sulfonic acids such as benzenesulfonic acid, and the like. Examples of the basic catalyst include ammoniacal bases such as aqueous ammonia and amines such as ethylamine and aniline. And the like.

The preparation of the hydrophilic coating solution can be carried out by dissolving a hydrophilic polymer having a silane coupling group at the terminal, preferably a cross-linking component, in a solvent such as ethanol, adding the above-mentioned catalyst if desired, and stirring. . The reaction temperature is from room temperature to 80 ° C., and the reaction time, that is, the time during which stirring is continued is preferably in the range of from 1 to 72 hours. A composite sol solution can be obtained.

The solvent used for preparing the hydrophilic polymer and preferably a hydrophilic coating solution composition containing a crosslinking component is not particularly limited as long as it can uniformly dissolve and disperse these. However, for example, aqueous solvents such as methanol, ethanol, and water are preferable.

As described above, the preparation of the organic-inorganic composite sol liquid (hydrophilic coating liquid composition) for forming the hydrophilic surface according to the present invention utilizes the sol-gel method. For the sol-gel method, see Shizuo Sakuhana “Sol-gel Method Science”
This is described in detail in such publications as Agne Shofusha Co., Ltd. (1988), Inkira Hirashima, "Functional thin film production technology by the latest sol-gel method", and the Sogo Gijutsu Center (published in 1992). The methods described therein can be applied to the preparation of the hydrophilic coating solution composition according to the present invention.

Various additives can be used in the hydrophilic coating solution composition according to the present invention according to the purpose, as long as the effects of the present invention are not impaired. For example, a surfactant can be added to improve the uniformity of the coating solution.

The hydrophilic layer can be formed by applying the hydrophilic coating solution composition prepared as described above to the surface of a support and drying the composition. The thickness of the hydrophilic layer can be selected depending on the purpose, but is generally 0.5 to 5.
0 g / m ² , preferably 1.0 to 3.0 g
/ M ² . When the coating amount is less than 0.5 g / m ² , the effect of hydrophilicity is hardly exhibited, and 5.0 g / m ^2.
If the ratio exceeds, both the sensitivity and the film strength tend to decrease, so that both are not preferred.

[Compound capable of forming a surface-hydrophobized region by heating or irradiation with radiation] A compound having an image forming function added to a hydrophilic layer, that is, forming a hydrophobized region by heating or radiation exposure Examples of the compound that can be used include a compound in which the physical properties of the compound itself change from hydrophilic to hydrophobic upon heating or irradiation with radiation, or hot-melt hydrophobic particles. (Compound that changes from hydrophilic to hydrophobic) As a compound that changes from hydrophilic to hydrophobic, JP-A-2000-12227
No. 2 (Japanese Patent Application No. 10-229783) can be mentioned a polymer having a functional group which changes from hydrophilic to hydrophobic by decarboxylation by heat as described in Japanese Patent Application No. 10-229783. Compounds are preferably exemplified. As a preferable physical property, it is particularly preferable that the contact angle of the surface of the coating film when applied with the polymer itself is 20 ° or less before heating and changes to 65 ° or more after heating. However, it is not limited to these.

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Further, as a specific example of a polymer having a functional group which changes from hydrophilic to hydrophobic in a side chain, Japanese Patent Application Laid-Open No.
Decarboxylation represented by the following general formula (1) such as a polymer having an ammonium base described in JP-A-317899 and a sulfonylacetic acid described in JP-A-2000-309174 (Japanese Patent Application No. 11-118295). A polymer having a type polarity conversion group can also be mentioned as a preferable one.

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(Wherein X is -O-, -S-, -Se-,
-NR^Three-, -CO-, -SO-, -SO_Two-, -PO
-, -SiR^ThreeR^Four-, -CS-, R¹, R^Two,
R^Three, R^FourEach independently represents a monovalent group, and M represents a positive charge
Represents an ion having. ) R¹, R^Two, R^Three, R^FourSpecific examples of -F, -Cl,
-Br, -I, -CN, -R^Five, -OR^Five, -OCO
R^Five, -OCOOR^Five, -OCONR^FiveR⁶, -OSO
_TwoR^Five, -COR^Five, -COOR^Five, -CONR^FiveR⁶, -N
R^FiveR⁶, -NR^Five-COR⁶, -NR^Five-COOR⁶, -N
R^Five-CONR⁶R⁷, -SR^Five, -SOR^Five, -SO
_TwoR^Five, -SO_ThreeR^FiveAnd the like. R^Five, R⁶, R⁷Utensils
Examples of hydrogen, alkyl, aryl, and alk
And an alkynyl group. Specific examples of these functional groups
Examples include functional groups as described above.

Of these, preferred as R ¹ , R ² , R ³ and R ⁴ are hydrogen, an alkyl group, an aryl group, an alkynyl group and an alkenyl group. The polarity conversion polymer compound in the present invention may be a homopolymer of one kind of monomer having a hydrophilic functional group as described above, or a copolymer of two or more kinds. Further, a copolymer with another monomer may be used as long as the effects of the present invention are not impaired. Specific examples of the polymer having a functional group that changes from hydrophobic to hydrophilic in the side chain according to the present invention [Exemplified Compounds (P-1) to (P)
-17)] is shown below, but the present invention is not limited to these.

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The proportion of the compound which changes from hydrophilic to hydrophobic in the total solids in the hydrophilic layer is preferably 0.01 to 94% by weight, more preferably 0.05 to 90% by weight.
Range.

(Heat-fusible hydrophobic particles) Examples of the heat-fusible hydrophobic particles include polystyrene described in EP 816070 and the like, and hydrophobic particles encapsulated in microcapsules described in WO94 / 23954 are also used for the same purpose. can do.

In the present invention, the heat-fusible hydrophobic particles, which are image forming components to be contained in the hydrophilic layer, are heated by heating.
Alternatively, the particles are fused and bonded to each other by heat generated by infrared laser irradiation to form a hydrophobic region (ink receiving region: image portion), and are particles made of a hydrophobic organic compound. From the viewpoint that particles are quickly fused by predetermined heating, the melting point (fusion temperature) of the hydrophobic organic compound is preferably in the range of 50 to 200 ° C. When the heat fusion temperature of the hot-melt hydrophobic particles is lower than 50 ° C., there is a concern that the particles may be softened or melted due to the influence of heat during drying of the coating film in the manufacturing process, or the influence of the environmental temperature during storage. Is not preferred. The heat fusing temperature is preferably 80 ° C. or more, and 100 ° C.
The above is more preferred. Although the higher the melting point, the higher the stability, the temperature is desirably 200 ° C. or lower from the viewpoint of recording sensitivity and handleability. As the hydrophobic organic compound constituting the hot-melt hydrophobic particles, specifically, for example, polystyrene, polyvinyl chloride, polymethyl methacrylate, polyvinylidene chloride, polyacrylonitrile, polyvinyl carbazole, etc., or a copolymer thereof Resins such as a coalescence or a mixture are exemplified. In addition, paraffin wax, micro wax, or polyolefin wax such as polyethylene wax and polypropylene wax, fatty acid wax such as stearamide, linoleamide, lauramide, myristylamide, palmitoamide, oleic amide, stearic acid, tridecanoic acid, palmitic acid, etc. Higher fatty acids and the like can also be suitably used.

In the present invention, as the image forming component to be contained in the hydrophilic layer, among the above-mentioned hydrophobic organic compounds, those in which the heat-fusible hydrophobic particles easily fuse and coalesce with each other by heat are used for the image forming property. From the viewpoint of preventing hydrophilicity from decreasing, those having a hydrophilic surface and easily dispersible in water are particularly preferable. As a measure of the hydrophilicity of the surface of the hot-melt hydrophobic particles, the contact angle (water droplet in the air) of the film when only the hot-melt hydrophobic particles are applied and dried at a temperature lower than the solidification temperature, It is preferable that the contact angle (water droplet in the air) of the film formed by drying at a temperature higher than the solidification temperature be lower. In order to make the hydrophilicity of the hot-melt hydrophobic particles surface in such a favorable state, a hydrophilic polymer or oligomer such as polyvinyl alcohol or polyethylene glycol, or a hydrophilic low-molecular compound is adsorbed on the hot-melt hydrophobic particles surface. The method for hydrophilizing the hydrophobic particles of the heat-fusible hydrophobic particles is not limited to these, and various known methods for hydrophilizing the surface can be applied. The average particle diameter of the hot-melt hydrophobic particles is preferably 0.01 to 20 μm, and among them, 0.1 to 20 μm is preferable.
05-2.0 μm is more preferable, and especially 0.1-1.
0 μm is optimal. If the average particle size is too large, the resolution tends to be poor, and if it is too small, the temporal stability may be deteriorated. The addition amount of the hot-melt hydrophobic particles is preferably 30 to 98% by weight of the solid content of the hydrophilic layer, and 40 to 9% by weight.
A range of 5% by weight is more preferred.

In order to obtain various characteristics, various compounds other than those described above may be added to the hydrophilic layer having an image forming function of the lithographic printing plate precursor according to the invention, if necessary. [Light-to-heat conversion material] When an image is recorded on the lithographic printing plate precursor of the present invention with an infrared laser or the like, a light-to-heat conversion material for converting light energy into heat energy is contained somewhere in the lithographic printing plate precursor. Is preferred. The portion containing the photothermal conversion material includes, for example, any of a hydrophilic layer also serving as an image forming layer, a support surface layer, and a support. In addition, between the support surface layer and the support, May be provided and a thin layer may be added thereto.

The light-to-heat conversion material that can be used in the lithographic printing plate precursor according to the invention is not particularly limited, and any material can be used as long as it can absorb light such as ultraviolet light, visible light, infrared light, and white light and convert it to heat. For example, carbon black, carbon graphite, pigment, phthalocyanine pigment, iron powder,
Examples thereof include graphite powder, iron oxide powder, lead oxide, silver oxide, chromium oxide, iron sulfide, and chromium sulfide. Particularly preferred are dyes, pigments or metals that effectively absorb infrared light having a wavelength of 760 nm to 1200 nm.

As the dye, commercially available dyes and known dyes described in literatures (eg, “Dye Handbook”, edited by The Society of Synthetic Organic Chemistry, published in 1970) can be used. Specific examples include dyes such as azo dyes, metal complex azo dyes, pyrazolone azo dyes, anthraquinone dyes, phthalocyanine dyes, carbonium dyes, quinone imine dyes, methine dyes, cyanine dyes, and metal thiolate complexes. Preferred dyes include, for example, JP-A-58-125246.
JP-A-59-84356, JP-A-59-2028
29, JP-A-60-78787, JP-A-58-173696 and JP-A-5-173696.
Methine dyes described in JP-A-8-181690 and JP-A-58-194595;
JP-A-58-224793, JP-A-59-481
No. 87, JP-A-59-73996, JP-A-60-52
No. 940, JP-A-60-63744 and the like, naphthoquinone dyes described in JP-A-58-112792 and the like, British Patent 434
No. 875, and the like.

Further, a near-infrared absorption sensitizer described in US Pat. No. 5,156,938 is preferably used, and a substituted arylbenzo (thio) pyrylium salt described in US Pat. No. 3,881,924 is also preferable. JP-A-57-142645 (U.S. Pat. No. 4,327,169);
Nos. 8-220143, 59-41363 and 59-
No. 84248, No. 59-84249, No. 59-146
Nos. 063 and 59-146061; cyanine dyes described in JP-A-59-216146; pentamethine thiopyrylium salts described in U.S. Pat. No. 4,283,475; Fairness 5-135
Nos. 14 and 5-19702 are also preferably used. Further, as another preferable example of the dye, a near-infrared absorbing dye described as formulas (I) and (II) in U.S. Pat. No. 4,756,993 can be exemplified. Among these dyes, particularly preferred are cyanine dyes, squarylium dyes, pyrylium salts, and nickel thiolate complexes.

The pigment used in the present invention includes:
Commercial Pigment and Color Index (CI) Handbook,
"Latest Pigment Handbook" (edited by Japan Pigment Technical Association, 1977), "Latest Pigment Application Technology" (CMC Publishing, 1986), "Printing Ink Technology" CMC Publishing, 1984)
Can be used. As the type of pigment, black pigment, yellow pigment, orange pigment, brown pigment,
Red pigment, purple pigment, blue pigment, green pigment, fluorescent pigment,
Metal powder pigments and other polymer-bound dyes can be used.
Specifically, insoluble azo pigments, azo lake pigments, condensed azo pigments, chelated azo pigments, phthalocyanine pigments, anthraquinone pigments, perylene and perinone pigments, thioindigo pigments, quinacridone pigments, dioxazine pigments, isoindolinone pigments And quinophthalone pigments, dyed lake pigments, azine pigments, nitroso pigments, nitro pigments, natural pigments, fluorescent pigments, inorganic pigments, carbon black, and the like. Preferred among these pigments is carbon black.

These pigments may be used without being subjected to a surface treatment, or may be used after being subjected to a surface treatment. Examples of the surface treatment include a method of surface coating a resin or wax, a method of attaching a surfactant, and a method of bonding a reactive substance (for example, a silane coupling agent, an epoxy compound, or a polyisocyanate) to the pigment surface. Conceivable. The above surface treatment methods are described in “Properties and Applications of Metallic Soap” (Koshobo), “Printing Ink Technology” (CMC Publishing, 1984) and “Latest Pigment Application Technology” (CMC Publishing, 1986). I have.

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. Pigment particle size 0.01μ
If it is less than m, it is not preferable in terms of stability of the dispersion in the coating solution of the photothermal conversion material-containing layer, and if it exceeds 10 μm, it is not preferable in terms of uniformity of the photothermal conversion material-containing layer. As a method for dispersing the pigment, a known dispersion technique used in the production of ink or toner 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,
The present roll mill, a pressure kneader and the like can be mentioned. Detail is,
It is described in "Latest Pigment Application Technology" (CMC Publishing, 1986).

These dyes or pigments are used in an amount of 0.01 to 50% by weight, preferably 0.1 to 50% by weight, based on the total solid content of the photothermal conversion material-containing layer.
1 to 10% by weight, particularly preferably 0.5 to 1 in the case of dyes
0% by weight, and in the case of a pigment, particularly preferably 3.1 to 10% by weight. If the amount of the pigment or dye is less than 0.01% by weight, the effect of improving sensitivity cannot be sufficiently obtained, and if it exceeds 50% by weight, the film strength of the photothermal conversion material-containing layer becomes weak.

(Support) The support used in the lithographic printing plate precursor according to the present invention is a plate which is dimensionally stable and has necessary properties such as strength, durability and flexibility. There is no particular limitation, for example, paper, plastic (eg, polyethylene, polypropylene, polystyrene, etc.) laminated paper, 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 and plastic films on which the above-mentioned metals are laminated or evaporated. No. As the support of the present invention, a polyester film or an aluminum plate is preferable, and among them, an aluminum plate having good dimensional stability and relatively low cost is particularly preferable.

Suitable aluminum plates are a pure aluminum plate and an alloy plate containing aluminum as a main component and containing a trace amount of a different element, and may be a plastic film on which aluminum is laminated or vapor-deposited. The foreign elements contained in aluminum alloys include silicon, iron, manganese, copper,
There are magnesium, chromium, zinc, bismuth, nickel, titanium and the like. The content of the foreign element in the alloy is at most 10% by weight or less. Particularly preferred aluminum in the present invention is pure aluminum. However, completely pure aluminum is difficult to produce due to refining technology, and therefore may contain a slightly different element. As described above, the composition of the aluminum plate applied to the present invention is not specified, and an aluminum plate of a conventionally known and used material can be appropriately used. The thickness of the aluminum plate used in the present invention is about 0.1 mm to 0.6 mm, preferably 0.15 mm to 0.4 mm, particularly preferably 0.1 mm to 0.4 mm.
It is 2 mm to 0.3 mm. The aluminum plate used as the base material may be subjected to a known surface treatment such as a surface roughening treatment and an anodic oxidation treatment, if necessary.

Further, when a plastic film such as a polyester film, which is another preferred embodiment, is used, the hydrophilic layer is formed from the viewpoint of the formability of the hydrophilic layer and the adhesion between the support and the hydrophilic layer. It is preferable to use a material whose surface is roughened by a known method.

The lithographic printing plate precursor thus obtained is exposed and developed by a known method to form a lithographic printing plate, which is used for printing a large number of sheets. In the image forming mechanism of the lithographic printing plate precursor according to the invention, a compound capable of forming a surface hydrophobized region such as hot-melt hydrophobic particles is heated, or fused to each other in a radiation irradiation region to form a hydrophobic region. In the non-heated area or the non-irradiated area, the hydrophilic layer will remain as it is in the non-heated area or the non-irradiated area. Since it is an image area, plate making by a simple water developing process or plate making directly mounted on a printing press without going through a special wet developing process is possible, and excellent on-press developability is exhibited.

The image formation of the lithographic printing plate precursor according to the invention is performed by heat. In addition, if the light-to-heat conversion material is used in combination, an image can be formed by heating by scanning exposure with laser light or the like in an infrared region. Examples of the method used for image formation include methods such as heat fixing, light fixing, pressure fixing, and solvent fixing. Specifically, direct image-like recording by a thermal recording head or the like, scanning exposure by an infrared laser, high illuminance flash exposure such as a xenon discharge lamp, or infrared lamp exposure is used. From the viewpoint of improving productivity, in order to perform direct plate making by computer to plate, it is preferable to perform melting using a laser. As the laser, a carbon dioxide laser, a nitrogen laser, an Ar laser,
Gas laser such as He / Ne laser, He / Cd laser, Kr laser, liquid (dye) laser, ruby laser, Nd
Laser such as / YAG laser, GaAs / GaAlA
Semiconductor lasers such as s and InGaAs lasers, KrF lasers, XeCl lasers, XeF lasers, and excimer lasers such as Ar ₂ can be used. Above all, wavelength 7
A semiconductor laser that emits infrared light having a wavelength of 100 to 1200 nm,
Exposure with a solid-state high-power infrared laser such as a YAG laser is preferable.

According to the above-described method, in the image-exposed hydrophilic layer, a hydrophobic region formed by heating and a hydrophilic region maintaining the surface properties of the hydrophilic layer are formed. By supplying the ink and the fountain solution, printing can be performed in a usual procedure. Alternatively, an image can be formed by mounting a lithographic printing plate precursor on a printing press equipped with an exposure device and performing imagewise exposure on the printing press.

EXAMPLES The present invention will be described below in detail with reference to examples, but the scope of the present invention is not limited by these examples.

(Synthesis Example 1: Synthesis of Specific Hydrophilic Polymer)
50 g of acrylamide, 3.4 g of mercaptopropyltrimethoxysilane, and 220 g of dimethylacetamide were placed in a 500 ml three-necked flask, and placed at 65 ° C. under a nitrogen stream.
2,2-azobis (2,4-dimethylvaleronitrile)
0.5 g was added. After maintaining the same temperature with stirring for 6 hours, the mixture was cooled to room temperature. The mixture was poured into 2 liters of ethyl acetate, and the precipitated solid was collected by filtration and washed with water to obtain a hydrophilic polymer (1). The weight after drying was 52.4 g. G
Weight average molecular weight 300 based on PC (polystyrene standard)
0 C, ¹³ C-NMR (DMSO-d ₆ )
At the end with a trimethoxysilyl group (50.0 ppm)
Was introduced and was confirmed to be a polymer having the structure of Exemplified Compound 1. [Example 1] (Preparation of support) An aluminum plate (material 1050) having a thickness of 0.30 mm was washed with trichlorethylene and degreased, and then a nylon brush and a pumice stone of 400 mesh were used.
The surface was grained using an aqueous suspension, and then thoroughly washed with water. This plate was etched by immersing it in a 25% by weight aqueous solution of sodium hydroxide at 45 ° C. for 9 seconds, washed with water, and further immersed in 2% by weight of nitric acid for 20 seconds and washed with water. At this time,
The amount of etching on the grained surface was about 3 g / m ² .
Next, this plate was subjected to a current density of 1 wt.
A DC anodic oxide film was provided at 5 A / dm ^{2 so} that the thickness of the anodic oxide film was 2.4 g / m ² , and then washed with water and dried to obtain a support.

(Formation of Hydrophilic Layer) The following components were uniformly mixed, and the mixture was stirred at room temperature for 2 hours to carry out hydrolysis to obtain a sol-like hydrophilic coating liquid composition 1. (Hydrophilic coating liquid composition 1) ・ Hydrophilic polymer (1) 21g ・ Tetramethoxysilane [crosslinking component] 62g ・ Ethanol 470g ・ Water 470g ・ Nitric acid aqueous solution (1N) 10g

Thereafter, using the above hydrophilic coating solution composition 1,
Preparation of coating liquid 1 for forming a hydrophilic layer having the following image forming ability
And the coated amount after drying on the aluminum support is 3 g.
/ M ^TwoAnd dried by heating at 100 ° C for 10 minutes
As a result, a lithographic printing plate precursor was obtained. (Coating solution for forming hydrophilic layer)-166 g of hydrophilic coating solution composition-Hot-melt polystyrene particles stabilized with a surfactant (1.5 wt% based on polymer) (particle size: 0.2 µm, melting point) 120 ° C.) (10% by weight aqueous dispersion) 400 g ・ Infrared absorbing dye I (the following compound) 10 g ・ Water 374 g

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The contact angle (water droplet in the air) on the surface of the hydrophilic layer having image forming ability on the obtained support was determined by using Kyowa Interface Science Co., Ltd.
Was measured using CA-Z, and it was 6.3 °, confirming that it had excellent hydrophilicity.

[Evaluation of lithographic printing plate precursor] The obtained lithographic printing plate precursor was subjected to an external drum rotation speed of 100 rpm and a plate surface energy of 200 m by a Creo Trendsetter 3244 VFS equipped with a water-cooled 40 W infrared semiconductor laser.
Exposure was performed under the conditions of J / cm ² and a resolution of 2400 dpi to form an image area on the surface of the exposed portion. The contact angle of water droplets on the infrared laser irradiation area surface of this printing plate was 102 °, which changed to hydrophobic, indicating that a hydrophobic area (ink-receiving area) was formed. After the exposure, the film was mounted on the following printer and used for printing without developing treatment. As a printing machine, SOR-M manufactured by Heidelberg Co., Ltd. was used, and IF201 was added to dampening water.
(2.5%), IF202 (0.75%) (manufactured by Fuji Photo Film Co., Ltd.), and GEOS-G ink (manufactured by Dainippon Ink and Chemicals, Inc.) as an ink. Immediately in the early stage of the printing process, a high quality printed matter was obtained. When printing was continued continuously thereafter, a good printed matter with no stain on the non-image area was obtained even after printing 5,000 sheets, and the non-image area maintained excellent hydrophilicity. It turned out that it was also excellent.

Comparative Example 1 In the hydrophilic coating solution composition 1 used in Example 1, polyacrylamide (weight average molecular weight 1,500) was used instead of the hydrophilic polymer (1) having a silane coupling group at the terminal. ) Was prepared in the same manner as in Example 1 except that the mixture prepared in Example 1 was used, and exposure, development, and printing were performed under the same conditions. At the beginning of printing, a good print without stains was obtained in the non-image area, but the stains gradually started and the image area also began to fade. On the 500th sheet, the distinction between the image area and the non-image area became indistinguishable, and it was found that the hydrophilicity of the non-image area was reduced by continuing printing.

[Example 2] (Formation of hydrophilic layer) The following components were uniformly mixed and mixed at room temperature.
Hydrolysis was performed by stirring for a period of time to obtain a sol-like hydrophilic coating liquid composition 2. (Hydrophilic coating liquid composition 2) 21 g hydrophilic polymer (9) Tetramethoxysilane [crosslinking component] 62 g Ethanol 470 g Water 470 g Nitric acid aqueous solution (1 N) 10 g

Thereafter, a coating liquid 2 for forming a hydrophilic layer having the following image forming ability was prepared using the above-mentioned hydrophilic coating liquid composition 2, and dried on the same aluminum support as used in Example 1 after drying. Apply so that the coating amount is 3 g / m ² ,
The resultant was dried by heating at 0 ° C. for 10 minutes to obtain a lithographic printing plate precursor. (Hydrophilic layer forming coating liquid 2) ・ Hydrophilic coating liquid composition 2 66g ・ Sulfonyl acetic acid polymer 40g [Exemplary compound (p-9) changing from hydrophilic to hydrophobic] ・ Infrared absorbing dye I 10g ・ Water 374g

The contact angle (water droplet in the air) of the surface of the hydrophilic layer having image forming ability on the obtained support was determined by using Kyowa Interface Science Co., Ltd.
Was measured using CA-Z, and it was 7.8 °, confirming that it had excellent hydrophilicity.

[Evaluation of Lithographic Printing Plate Precursor] The resulting lithographic printing plate precursor was exposed in the same manner as in Example 1 to form an image area on the exposed surface. The water droplet contact angle of the surface of the printing plate with the infrared laser irradiation was 98 °, which changed to hydrophobic, indicating that a hydrophobic region (ink receiving region) was formed. After the exposure, printing was performed in the same manner as in Example 1 without performing development processing, and a high-quality printed matter was obtained immediately in the early stage of the printing process. When printing was continued continuously thereafter, a good printed matter with no stain on the non-image area was obtained even after printing 5,000 sheets, and the non-image area maintained excellent hydrophilicity. It turned out that it was also excellent. From this, even in a lithographic printing plate precursor using a compound that changes from hydrophilic to hydrophobic as a compound capable of forming a surface-hydrophobic region, the effect of the present invention can be improved similarly to the case of using hot-melt hydrophobic particles. It was confirmed to play.

Example 3 A coating liquid 1 for forming a hydrophilic layer having the same image forming ability as that used in Example 1 was applied on a corona-treated polyethylene terephthalate film support.
Was applied so that the coating amount after drying was 3 g / m ² ,
The resultant was dried by heating at 00 ° C. for 10 minutes to obtain a lithographic printing plate precursor.

The contact angle (water droplet in the air) on the surface of the hydrophilic layer having an image forming ability on the obtained support was measured by using Kyowa Interface Science Co., Ltd.
Was 6.5 °, which was confirmed to have excellent hydrophilicity.

[Evaluation of lithographic printing plate precursor] The obtained lithographic printing plate precursor was exposed in the same manner as in Example 1 to form an image area on the exposed surface. The water droplet contact angle on the surface of the printing plate with the infrared laser irradiation was 105 °, indicating that a hydrophobic region (ink-receiving region) was formed. After the exposure, printing was performed in the same manner as in Example 1 without performing development processing, and a high-quality printed matter was obtained immediately in the early stage of the printing process. When printing was continued continuously after that, a good printed matter with no stain on the non-image area was obtained even after printing 5,000 sheets, and the non-image area maintained excellent hydrophilicity. It turned out that it was also excellent. From this, it was confirmed that the effects of the present invention can be exerted even on a lithographic printing plate precursor using a resin film as a support.

[0091]

According to the lithographic printing plate precursor of the present invention, high hydrophilicity is maintained even under severe printing conditions, printing durability is good, and a large number of high-quality printed matters having no stain on non-image areas are obtained. Can be Furthermore, plate making by scanning exposure based on a digital signal is possible, and plate making by a simple water development processing operation, or it is possible to mount and print on a printing machine without performing development processing. This is advantageous in that a lithographic printing plate precursor exhibiting on-press developability can be provided.

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2H025 AA12 AB03 AC08 AD01 BH03 CB08 CB34 CB41 CB42 CB43 CB45 CB47 CC17 CC20 FA10 FA17 2H096 AA06 BA20 CA03 EA04 EA23 GA08 LA30 2H114 AA04 AA22 AA24 DA01 DA45

Claims (2)

[Claims] 1. A support having (A) a hydrophilic graft chain and a crosslinked structure formed by hydrolysis and condensation polymerization of a metal alkoxide selected from Si, Ti, Zr, and Al on a support. A lithographic printing plate precursor comprising: a hydrophilic layer; and a compound capable of forming a hydrophobic region on the surface of the hydrophilic layer by heating or irradiation with radiation. 2. The lithographic printing plate precursor according to claim 1, wherein the hydrophilic layer having a crosslinked structure contains a polymer compound represented by the following general formula (I). Embedded image In the formula (I), R ¹ , R ² , R ³ and R ⁴ each independently represent a hydrogen atom or a hydrocarbon group having 1 to 8 carbon atoms, m represents 0, 1 or 2; Represents an integer of 8. L represents a single bond or an organic linking group, Y is -NHCOR ^5, -
^{_{CONH 2, -CON (R 5)}} 2, -COR 5, -OH, -
Represents CO ₂ M or —SO ₃ M, wherein R ⁵ has 1 carbon atom
And M represents a hydrogen atom, an alkali metal, an alkaline earth metal or onium.