JP2012048176A - Lithographic printing plate precursor and method for forming lithographic printing plate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a lithographic printing plate excellent in developability and antifouling property without deterioration in printing durability, by which a plate can be made up directly from digital data by performing recording using laser light and can be developed on a printing machine by solution with pH 11 or less.SOLUTION: A lithographic printing plate precursor includes a support body and at least one or more layers including an image recording layer where one of the at least one or more layers contacting the support layer contains polymer formed from a repeating unit including partial structures expressed by following general formulas (I) or (II).

Description

  The present invention relates to a lithographic printing plate precursor and a lithographic printing plate preparation method that can be directly made from a digital signal from a computer or the like using various lasers, and a lithographic printing plate precursor and a lithographic printing plate that are particularly suitable for simple processing. It relates to a manufacturing method.

  Solid lasers, semiconductor lasers, and gas lasers that emit ultraviolet light, visible light, and infrared light having a wavelength of 300 nm to 1200 nm are easily available in high output and small size. It is very useful as a recording light source when making a plate directly from digital data. Various studies have been made on recording materials that are sensitive to these various laser beams. As a typical example, firstly, positive recording described in Patent Document 1 as a material that can be recorded with an infrared laser having an image recording wavelength of 760 nm or more. Materials, acid-catalyzed cross-linking negative recording materials described in Patent Document 2, and the like. Secondly, there is a radical polymerization type negative recording material described in Patent Document 3 as a recording material compatible with ultraviolet light or visible light laser of 300 nm to 700 nm.

In addition, in a conventional lithographic printing plate precursor (hereinafter also referred to as PS plate), after image exposure, a step (development treatment) of dissolving and removing a non-image portion using a strong alkaline aqueous solution is indispensable and developed. A post-treatment step is also necessary in which the printing plate is washed with water, treated with a rinse solution containing a surfactant, or treated with a desensitizing solution containing gum arabic or starch derivatives. The point that these additional wet treatments are indispensable is a big problem for the conventional PS plate. Even if the first half (image exposure) of the plate making process is simplified by the digital processing, the effect of the simplification is insufficient in the wet processing in which the second half (development processing) is complicated.
Particularly in recent years, consideration for the global environment has become a major concern for the entire industry, and from consideration for the environment, processing with a developing solution closer to the neutral range and reduction of waste liquid have been raised as issues. Yes. In particular, it is desirable that the wet post-treatment is simplified or changed to a dry treatment.

  From such a viewpoint, as a method for simplifying the processing step, there is a one-liquid process or a one-bath process in which development and gum solution processing are performed simultaneously. That is, after image exposure of the printing plate precursor without performing the pre-water washing step, the protective layer is removed, the non-image area is removed, and the gum solution treatment is simultaneously performed in one liquid or one bath, and the post-water washing step is not performed. This is a simple development method that enters the printing process. A lithographic printing plate precursor suitable for such simple development has an image recording layer that is soluble in a non-strongly alkaline developer, and further improves the stain resistance of non-image areas, because the post-washing step is omitted. Therefore, a hydrophilic support surface is required. However, with conventional PS plates, it has been virtually impossible to achieve high printing durability while satisfying such requirements.

  Therefore, a lithographic printing plate precursor in which the support is hydrophilized with polyvinylphosphonic acid has been proposed in order to satisfy such requirements (for example, see Patent Document 4). Regarding the plate making, after image exposure with an ultraviolet laser, development is performed with a developer having a pH of 9.8.

However, a hydrophilic treatment such as polyvinylphosphonic acid has insufficient hydrophilicity for improving the stain resistance, and there is a problem in the stain resistance as a printing plate.
Further, a lithographic printing plate precursor in which a layer having a monomer having a sulfonic acid group and a binder polymer obtained by copolymerizing a support adsorptive group is formed on the support surface in place of polyvinylphosphonic acid has been proposed (for example, However, hydrophilicity is still insufficient to introduce a hydrophobic polymerizable group for developing printing durability. Thus, it is extremely difficult to satisfy both printing durability and stain resistance, a simple processing type lithographic printing plate having good stain resistance and sufficient printing durability has not been known so far.

One method of simplifying the processing process is to mount the exposed lithographic printing plate precursor on the cylinder of the printing machine, and supply dampening water and ink while rotating the cylinder. There is a method called on-press development that removes non-image areas. That is, the lithographic printing plate precursor is image-exposed and then mounted on a printing machine as it is, and the development process is completed in a normal printing process.
Such a lithographic printing plate precursor suitable for on-press development has an image forming layer soluble in dampening water or an ink solvent, and is suitable for development on a printing press placed in a bright room. It is necessary to have good light room handling. However, with the conventional PS plate, it is practically impossible to sufficiently satisfy such a requirement.
Therefore, in order to satisfy such requirements, a lithographic printing plate precursor in which an image recording layer in which thermoplastic hydrophobic polymer fine particles are dispersed in a hydrophilic binder polymer is provided on a hydrophilic support has been proposed. (For example, refer to Patent Document 6). In making the plate, image exposure is performed with an infrared laser, and the thermoplastic hydrophobic polymer fine particles are combined (fused) with heat generated by photothermal conversion to form an image, and then the plate is mounted on a cylinder of a printing press, On-press development is performed by supplying at least one of fountain solution and ink. This lithographic printing plate precursor has handleability in a bright room because the image recording area is an infrared region.

However, an image formed by coalescence (fusion) of thermoplastic hydrophobic polymer fine particles has insufficient strength and has a problem in printing durability as a lithographic printing plate.
In addition, a lithographic printing plate precursor including microcapsules containing a polymerizable compound in place of the thermoplastic fine particles has been proposed (see, for example, Patent Document 7). The lithographic printing plate precursor according to such a proposal has an advantage that the polymer image formed by the reaction of the polymerizable compound is superior in strength to the image formed by fusing fine particles.
In addition, since the polymerizable compound has high reactivity, many methods for isolating it using microcapsules have been proposed. It has been proposed to use a thermally decomposable polymer for the shell of the microcapsule.

  However, the conventional lithographic printing plate precursors described in Patent Documents 6 and 7 and the like are not sufficient in printing durability of images formed by laser exposure, and further improvements are required. That is, in these simple processing type lithographic printing plate precursors, a support having a highly hydrophilic surface is used, and as a result, the image portion is easily peeled off from the support by dampening water during printing. Printing durability was not obtained. On the contrary, if the support surface is made hydrophobic, the ink also adheres to the non-image area during printing, and printing stains occur. Thus, it is extremely difficult to achieve both printing durability and stain resistance, an on-press development type lithographic printing plate precursor having good stain resistance and sufficient printing durability has not been known so far. .

  Further, Patent Document 8 discloses a lithographic printing plate support having a hydrophilic layer made of a polymer compound that is chemically bonded directly to the support surface and has a hydrophilic functional group on the support. Yes. Patent Documents 9 and 10 disclose a hydrophilic polymer having a reactive group that can be chemically bonded to an aluminum support or a silicate-treated aluminum support directly or via a component having a crosslinked structure on the surface of the support. A support for a lithographic printing plate having a hydrophilic surface formed by chemically bonding is disclosed. Patent Document 11 has, on a support, an image recording layer containing a polymerization initiator, a polymerizable compound, and a binder polymer that dissolves or swells in water or an aqueous alkali solution. In the image recording layer or other layers, A lithographic printing plate precursor containing a copolymer comprising a repeating unit having at least one ethylenically unsaturated bond and a repeating unit having at least one functional group that interacts with the support surface is disclosed. However, the lithographic printing plate precursor described in Patent Document 8 and the like has a problem that the stain resistance is still insufficient. In particular, when printing is performed after a lapse of time since the printing plate is produced, there is a problem that the stain resistance decreases.

US Pat. No. 4,708,925 JP-A-8-276558 U.S. Pat. No. 2,850,445 JP 2009-98590 A JP 2009-216926 A Japanese Patent No. 2938397 JP 2002-326470 A JP 2001-166491 A JP 2008-213177 A JP 2009-47754 A JP 2006-78999 A

  Therefore, the object of the present invention is to make plate making directly from digital data such as a computer by recording using various laser beams, and in particular, it can be developed on an aqueous solution having a pH of 11 or less or on a printing machine, and the printing durability is improved. An object of the present invention is to provide a lithographic printing plate precursor and a method for preparing the lithographic printing plate, which can provide a lithographic printing plate having excellent developability and excellent stain resistance (including stain resistance after aging) without loss.

  As a result of intensive studies, the present inventors have found that the above problems can be solved by using the following lithographic printing plate precursor and lithographic printing plate preparation method. That is, the present invention is as follows.

<1> A lithographic printing plate precursor having a support and at least one layer including an image recording layer, wherein the layer in contact with the support among the at least one layer is represented by the following general formula (I) or A lithographic printing plate precursor comprising a polymer (A) having a repeating unit (a1) having a partial structure represented by (II).

(In general formula (I) or (II),
L ¹¹ and L ²¹ each independently represent a single bond or a divalent linking group, and X ⁺ represents -N ⁺ R ¹ R ^2- , -S ⁺ R ^1- , -I ⁺ -or -P ⁺ R ¹ R. ² - represents, a ^- is _{^{-SO 3 -, -CO 2 -,}} -PO 3 H - or -OPO ₃ H ^- represents a.
Y ⁺ represents ^{-N + R 3 R 4 R 5} , -S + R 3 R 4, -I + R 3 or ^{-P + R 3 R 4 R 5} .
R ¹ , R ² , R ³ , R ⁴ and R ⁵ each independently represents an alkyl group or an aryl group which may contain a hetero atom.
At least two of R ¹ , R ² and L ¹¹ , or at least two of R ¹ , R ² and L ¹² may be linked to each other to form a ring. At least two of R ³ , R ⁴ and L ²² may be connected to each other to form a ring.
L ¹² and L ²² each independently represents a divalent linking group containing an atom having at least one sp ² hybrid orbital or an sp hybrid orbital, or a divalent linking group containing at least one cyclic alkylene group. To express.
'Represents a site directly connected to the main chain. )
<2> The layer in contact with the support among the at least one layer is the image recording layer or an undercoat layer provided between the support and the image recording layer. Lithographic printing plate precursor.
<3> The lithographic printing plate precursor as described in <1> or <2>, wherein the polymer (A) is a polymer having a repeating unit having a partial structure represented by the general formula (I).
<4> The lithographic printing plate precursor as described in any one of <1> to <3>, wherein A ⁻ in the general formula (I) is —SO ₃ ^— or —CO ₂ ^— .
<5> X ⁺ in the general formula (I) represents -N ⁺ R ¹ R ^2- , Y ⁺ in the general formula (II) represents -N ⁺ R ³ R ⁴ R ⁵ , <1> Or the lithographic printing plate precursor as described in <2>.
<6> L ^{12 in the} general formula (I) and L ²² in the general formula (II) each independently include a hetero atom in the linking group, and are selected from the following group. The lithographic printing plate precursor as described in any one of <1> to <5>, which is a divalent linking group containing at least one group.

(In the above formula, * represents a linking site. R represents an alkyl group or a hydroxyl group.)
<7> L ^{12 in the} general formula (I) and L ²² in the general formula (II) each independently include a hetero atom in the linking group, and are selected from the following group. The lithographic printing plate precursor as described in <6>, which is a divalent linking group containing at least one group.

(In the above formula, * represents a linking site. R represents an alkyl group or a hydroxyl group.)
<8> In ^{L 22} in the general formula (I) ^{L 12} and Formula in in (II), ^{X +} and A ^- or an oxygen atom directly linked to ^{L 22} of phosphoric acid ester and for coupling ^{Y +} The lithographic printing plate precursor as described in any one of <1> to <7>, wherein the total of the shortest number of atoms used in is from 4 to 8.
<9> In any one of <1> to <8>, the polymer (A) further includes a repeating unit (a2) having at least one functional group that interacts with the surface of the support. The lithographic printing plate precursor described.
<10> Any of <1> to <9>, wherein the image recording layer further contains (B) a polymerization initiator, (C) a polymerizable compound, (D) a sensitizing dye, and (E) a binder polymer. The lithographic printing plate precursor as described in 1 above.
<11> The lithographic printing plate precursor as described in <10>, wherein the (E) binder polymer is a (meth) acrylic polymer, a polyurethane resin or a polyvinyl butyral resin.
<12> The image recording layer in the non-image area in the presence of a developer having a pH of 2 to 14 after imagewise exposure of the lithographic printing plate precursor according to any one of <1> to <11> A method for producing a lithographic printing plate, comprising the step of removing
<13> The lithographic printing plate precursor as described in any one of <1> to <11> above is imagewise exposed, and then printing ink and fountain solution are supplied on the printing press to form an image in a non-image area. A method for producing a lithographic printing plate, comprising a step of removing a recording layer.
<14> A radically polymerizable unsaturated group-containing monomer represented by the following general formula (III) or (IV).

(In general formula (III) or (IV),
R ^X , R ^Y and R ^Z each independently represents a hydrogen atom or an alkyl group.
L ¹¹ and L ²¹ each independently represent a single bond or a divalent linking group, and X ⁺ represents -N ⁺ R ¹ R ^2- , -S ⁺ R ^1- , -I ⁺ -or -P ⁺ R ¹ R. ² - represents, a ^- is _{^{-SO 3 -, -CO 2 -,}} -PO 3 H - or -OPO ₃ H ^- represents a.
Y ⁺ represents ^{-N + R 3 R 4 R 5} , -S + R 3 R 4, -I + R 3 or ^{-P + R 3 R 4 R 5} .
R ¹ , R ² , R ³ , R ⁴ and R ⁵ each independently represents an alkyl group or an aryl group which may contain a hetero atom.
At least two of R ¹ , R ² and L ¹¹ , or at least two of R ¹ , R ² and L ¹² may be linked to each other to form a ring. At least two of R ³ , R ⁴ and L ²² may be connected to each other to form a ring.
L ¹² and L ²² each independently represents a divalent linking group containing an atom having at least one sp ² hybrid orbital or an sp hybrid orbital, or a divalent linking group containing at least one cyclic alkylene group. To express. )
<15> The radical polymerizable unsaturated group-containing monomer according to <14>, which is represented by the general formula (III).
<16> The radical polymerizable unsaturated group-containing monomer according to <14> or <15>, wherein A ⁻ in the general formula (III) is —SO ₃ ^— or —CO ₂ ^— .
<17> The radical polymerizable unsaturated group-containing monomer according to any one of <14> to <16>, wherein X ⁺ in the general formula (III) is —N ⁺ R ¹ R ² —.
<18> A divalent group selected from the following group, wherein L ^{12 in the} general formula (III) and L ²² in the general formula (IV) each independently include a hetero atom in the linking group. The radical polymerizable unsaturated group-containing monomer according to any one of <14> to <17>, which is a divalent linking group containing at least one group.

(In the above formula, * represents a linking site. R represents an alkyl group or a hydroxyl group.)
<19> Divalent selected from the following group, wherein L ^{12 in the} general formula (III) and L ²² in the general formula (IV) each independently include a hetero atom in the linking group. The radical polymerizable unsaturated group-containing monomer according to <18>, which is a divalent linking group containing at least one group.

(In the above formula, * represents a linking site. R represents an alkyl group or a hydroxyl group.)
<20> In ^{L 22} in the ^{L 12} and the of the general formula ^{(III) (IV), X} + and A ^- or an oxygen atom directly linked to ^{L 22} of phosphoric acid ester directly connected to for the ^{Y +} <14>-<19> The radically polymerizable unsaturated group-containing monomer according to any one of <14> to <19>, wherein the total of the shortest number of atoms used in the method is 4-8.
<21> A polymer having a repeating unit (a1) having a partial structure represented by the following general formula (I) or (II).

(In general formula (I) or (II),
L ¹¹ and L ²¹ each independently represent a single bond or a divalent linking group, and X ⁺ represents -N ⁺ R ¹ R ^2- , -S ⁺ R ^1- , -I ⁺ -or -P ⁺ R ¹ R. ² - represents, a ^- is _{^{-SO 3 -, -CO 2 -,}} -PO 3 H - or -OPO ₃ H ^- represents a.
Y ⁺ represents ^{-N + R 3 R 4 R 5} , -S + R 3 R 4, -I + R 3 or ^{-P + R 3 R 4 R 5} .
R ¹ , R ² , R ³ , R ⁴ and R ⁵ each independently represents an alkyl group or an aryl group which may contain a hetero atom.
At least two of R ¹ , R ² and L ¹¹ , or at least two of R ¹ , R ² and L ¹² may be linked to each other to form a ring. At least two of R ³ , R ⁴ and L ²² may be connected to each other to form a ring.
L ¹² and L ²² each independently represent a divalent linking group containing an atom having at least one sp ² hybrid orbital or an sp hybrid orbital, or a divalent linking group containing at least one cyclic alkylene. .
'Represents a site directly connected to the main chain. )
<22> A hydrophilic film formed from the polymer according to <21>.

The lithographic printing plate precursor and the lithographic printing plate production method of the present invention can be directly made using various lasers from digital signals from a computer or the like, so-called direct plate making and high productivity lithographic printing plate, pH 11 or lower aqueous solution In addition, it is possible to provide a lithographic printing plate that can be developed on a printing press and has good developability and good stain resistance (including stain resistance after aging) without impairing printing durability.
The radically polymerizable unsaturated group-containing monomer of the present invention can be used for the production of a polymer used in the lithographic printing plate precursor.
In addition, the polymer of the present invention can be used for antifouling materials, biocompatible materials, oil repellent materials, and the like, by forming a film, thereby enabling surface coating with excellent hydrophilicity.

It is explanatory drawing which shows the structure of an automatic developing processor. It is explanatory drawing which shows the structure of an automatic developing processor.

  In the present specification, regarding the notation of the group in the compound represented by the general formula, when there is no substitution or no substitution, there is no other special provision when the group can further have a substituent. As long as it includes not only an unsubstituted group but also a group having a substituent. For example, in the general formula, if there is a description that “R represents an alkyl group, an aryl group or a heterocyclic group”, “R represents an unsubstituted alkyl group, a substituted alkyl group, an unsubstituted aryl group, a substituted aryl group, an Represents a substituted heterocyclic group or a substituted heterocyclic group.

Hereinafter, the lithographic printing plate precursor according to the invention will be described in detail.
The lithographic printing plate precursor according to the invention is a lithographic printing plate precursor having a support and at least one layer including an image recording layer, and the layer in contact with the support in the at least one layer is generally Containing a polymer (A) having a repeating unit (a1) having a partial structure represented by the formula (I) or (II) (hereinafter also referred to as a specific polymer compound (A)), It contains a polymer (A) having a side chain having a structure represented by I) or (II).
In the present invention, the layer in contact with the support among the at least one layer is preferably the image recording layer or an undercoat layer provided between the support and the image recording layer.
The image recording layer preferably further contains (B) a polymerization initiator, (C) a polymerizable compound, (D) a sensitizing dye, and (E) a binder polymer. The image recording layer in the invention may further contain other components as required.

The effect | action in this invention is estimated as follows. That is, the partial structure represented by the general formula (I) or (II) has a highly hydrophilic zwitterion, a divalent linking group containing an atom having an sp hybrid orbital or an sp ² hybrid orbital, or By making a divalent linking group containing at least one cyclic alkylene group a linking group of a partial structure having a positive charge and a partial structure having a negative charge, the positive charge and the negative charge are difficult to approach spatially. Become. Thus, it is presumed that poor development caused by being chelate-like stabilized with the polar component in the image recording layer can be suppressed, and high developability can be expressed.

  Further, the image recording layer in contact with the support or the undercoat layer provided between the support and the image recording layer includes a repeating unit (a1) having a partial structure represented by the general formula (I) or (II). By containing the coalescence (A), the hydrophilicity of the non-image area is increased, and the penetration of the developer / fountain solution into the non-image area is promoted to obtain a printed matter excellent in developability or on-press developability. Presumed to be possible. In addition, among the ink and dampening water supplied during printing, the dampening water is strongly adsorbed to the non-image area, thereby preventing the ink from adhering to the non-image area and obtaining a printed matter having excellent stain resistance. It is estimated that

In addition, the monomer corresponding to the repeating unit (a1) having a partial structure represented by the general formula (I) or (II) has a positive charge and a negative charge that are difficult to spatially approach. Cancellation is suppressed, stabilization in the presence of water in both water charges is promoted, and hydrophilicity is excellent. Thus, it is presumed that a film having excellent surface hydrophilicity can be obtained by polymerizing the monomer and introducing it into the polymer.
Hereinafter, the components of the lithographic printing plate precursor according to the invention will be described in detail.

(A) Specific polymer compound The specific polymer compound (A) in the present invention is a polymer having a repeating unit (a1) having a partial structure represented by the following general formula (I) or (II), that is, A polymer having a partial structure represented by formula (I) or (II) in the side chain.

(In general formula (I) or (II),
L ¹¹ and L ²¹ each independently represent a single bond or a divalent linking group, and X ⁺ represents -N ⁺ R ¹ R ^2- , -S ⁺ R ^1- , -I ⁺ -or -P ⁺ R ¹ R. ² - represents, a ^- is _{^{-SO 3 -, -CO 2 -,}} -PO 3 H - or -OPO ₃ H ^- represents a.
Y ⁺ represents ^{-N + R 3 R 4 R 5} , -S + R 3 R 4, -I + R 3 or ^{-P + R 3 R 4 R 5} .
R ¹ , R ² , R ³ , R ⁴ and R ⁵ each independently represent an alkyl group or an aryl group which may contain a hetero atom.
At least two of R ¹ , R ² and L ¹¹ , or at least two of R ¹ , R ² and L ² may be linked to each other to form a ring. At least two of R ³ , R ⁴ and L ²² may be connected to each other to form a ring.
L ¹² and L ²² each independently represents a divalent linking group containing an atom having at least one sp ² hybrid orbital or an sp hybrid orbital, or a divalent linking group containing at least one cyclic alkylene group. To express.
'Represents a site directly connected to the main chain. )

In the above general formula (I) or (II), the divalent linking groups represented by L ¹¹ and L ²¹ are 1 to 60 carbon atoms, 0 to 10 nitrogen atoms, and 0 to 50 atoms. It is preferably composed of 1 to 100 hydrogen atoms and 0 to 20 sulfur atoms. More specifically, the following structural units or groups formed by combining them can be exemplified.

In the above structure, R ^a and R ^b each independently represent a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, or a halogen atom. n represents an integer of 1 to 4.

In the general formula (I) or (II), the divalent linking group represented by L ¹¹ or L ²¹ is preferably —COOL ³ —, —CONHL ³ — or a phenylene group, and —COOL ³ — or particularly preferably - -CONHL ^3.

In the general formula (I) or (II), L ³ represents a divalent linking group, and the linking group as L ³ is preferably an alkylene group which may be substituted, and may be substituted having 1 to 10 carbon atoms. An alkylene group is more preferable, and an optionally substituted alkylene group having 1 to 5 carbon atoms is more preferable.

In the general formula (I) or (II), the alkyl group or aryl group represented by R ¹ , R ² , R ³ , R ⁴ or R ⁵ is an optionally substituted alkyl group having 1 to 50 carbon atoms. Alternatively, an aryl group is preferable, an optionally substituted alkyl group having 1 to 40 carbon atoms or an aryl group is more preferable, and an optionally substituted alkyl group having 1 to 30 carbon atoms which may be substituted is more preferable. . R ¹ , R ² , R ³ , R ⁴ and R ⁵ may each independently contain a hetero atom.

In the general formulas (I) and (II), the substituent of the alkyl group and aryl group represented by R ¹ , R ² , R ³ , R ⁴ , R ⁵ is a monovalent nonmetallic atomic group excluding hydrogen. Is used. Preferred examples include halogen atoms (-F, -Br, -Cl, -I), hydroxyl groups, alkoxy groups, aryloxy groups, mercapto groups, alkylthio groups, arylthio groups, alkyldithio groups, aryldithio groups, amino groups, N-alkylamino group, N, N-diarylamino group, N-alkyl-N-arylamino group, acyloxy group, carbamoyloxy group, ア ル キ ル -alkylcarbamoyloxy group, N-arylcarbamoyloxy group, N, N-dialkyl Carbamoyloxy group, N, N-diarylcarbamoyloxy group, N-alkyl-N-arylcarbamoyloxy group, alkylsulfoxy group, arylsulfoxy group, acylthio group, acylamino group, N-alkylacylamino group, N-aryl Acylamino group, ureido group, N ′ Alkylureido group, N ′, N′-dialkylureido group, N′-arylureido group, N ′, N′-diarylureido group, N′-alkyl-N′-arylureido group, N-alkylureido group, N -Arylureido group, N'-alkyl-N-alkylureido group, N'-alkyl-N-arylureido group, N ', N'-dialkyl-N-alkylureate group, N', N'-dialkyl- N-arylureido group, N′-aryl-Ν-alkylureido group, N′-aryl-N-arylureido group, N ′, N′-diaryl-N-alkylureido group, N ′, N′-diaryl- N-arylureido group, 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 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-arylcarbamoyl group, alkylsulfinyl group, arylsulfinyl group, alkylsulfonyl group, arylsulfonyl group, sulfo group (—SO ₃ H) and its conjugate base group (hereinafter referred to as sulfonate 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-diarylsulfamoyl group, N-alkyl -N-arylsulfamoyl group phosphono group -PO ₃ H ₂₎ and its conjugated base group (hereinafter referred to as phosphonato group), a dialkyl phosphono group _(-PO 3 _(alkyl) 2), diaryl phosphono group _(-PO 3 _(aryl) 2), alkylaryl Phosphono group (—PO ₃ (alkyl) (aryl)), monoalkyl phosphono group (—PO ₃ H (alkyl)) and its conjugate base group (hereinafter referred to as alkyl phosphonate group), monoaryl phosphono group (—PO ₃ H (aryl)) and its conjugate base group (hereinafter referred to as arylphosphonate group), phosphonooxy group (—OPO ₃ H ₂ ) and its conjugate base group (hereinafter referred to as “phosphonateoxy group”). ), dialkyl phosphonooxy group _{(-OPO 3 (alkyl) 2)} , diaryl phosphonooxy group (-OPO ₃ ( _RYL) 2), alkylaryl phosphonooxy group (-OPO (alkyl) (aryl) ), monoalkyl phosphonooxy group _(-OPO 3 H _(alkyl)) and its conjugated base group (hereinafter, alkyl phosphonophenyl group Monoarylphosphonooxy group (—OPO ₃ H (aryl)) and its conjugate base group (hereinafter referred to as arylphosphonatooxy group), morpholino group, cyano group, nitro group, aryl group, alkenyl group , An alkynyl group.

  Among these, particularly preferred substituents include a halogen atom (—F, —Br, —Cl, —I), a hydroxyl group, an alkoxy group, an aryloxy group, a mercapto group, an amino group, and a dialkylamino group.

Specific examples of the alkyl group of R ¹ , R ² , R ³ , R ⁴ , and R ⁵ include methyl group, ethyl group, propyl group, butyl group, pentyl group, hexyl group, heptyl group, octyl group, nonyl group, decyl group. Group, undecyl group, dodecyl group, tridecyl group, hexadecyl group, octadecyl group, eicosyl group, isopropyl group, isobutyl group, s-butyl group, t-butyl group, isopentyl group, neopentyl group, 1-methylbutyl group, isohexyl group, 2-ethylhexyl group, 2-methylhexyl group, cyclohexyl group, cyclopentyl group, 2-norbornyl group, chloromethyl group, bromomethyl group, 2-chloroethyl group, trifluoromethyl group, methoxymethyl group, methoxyethoxyethyl group, allyloxy Methyl group, phenoxymethyl group, methylthiomethyl group, Ruthiomethyl group, ethylaminoethyl group, diethylaminopropyl group, morpholinopropyl group, acetyloxymethyl group, benzoyloxymethyl group, N-cyclohexylcarbamoyloxyethyl group, N-phenylcarbamoyloxyethyl group, acetylaminoethyl group, N-methyl Benzoylaminopropyl group, 2-oxoethyl group, 2-oxopropyl group, carboxypropyl group, methoxycarbonylethyl group, allyloxycarbonylbutyl group, chlorophenoxycarbonylmethyl group, carbamoylmethyl group, N-methylcarbamoylethyl group, N, N-dipropylcarbamoylmethyl group, N- (methoxyphenyl) carbamoylethyl group, N-methyl-N- (sulfophenyl) carbamoylmethyl group, sulfobutyl group, sulfona Butyl group, sulfamoylbutyl group, N-ethylsulfamoylmethyl group, N, N-dipropylsulfamoylpropyl group, N-tolylsulfamoylpropyl group, N-methyl-N- (phosphonophenyl) sulfur Famoyloctyl group, phosphonobutyl group, phosphonatohexyl group, diethylphosphonobutyl group, diphenylphosphonopropyl group, methylphosphonobutyl group, methylphosphonatobutyl group, tolylphosphonohexyl group, tolylphosphonatohexyl group , Phosphonooxypropyl group, phosphonatooxybutyl group, benzyl group, phenethyl group, α-methylbenzyl group, 1-methyl-1-phenylethyl group, p-methylbenzyl group, cinnamyl group, allyl group, 1-propenyl Methyl group, 2-butenyl group, 2-methylary Group, 2-methyl propenyl methyl group, 2-propynyl group, 2-butynyl, 3-butynyl group.

  Specific examples of the aryl group include phenyl, biphenyl, naphthyl, tolyl, xylyl, mesityl, cumenyl, chlorophenyl, bromophenyl, chloromethylphenyl, hydroxyphenyl, methoxyphenyl, ethoxy Phenyl group, phenoxyphenyl group, acetoxyphenyl group, benzoyloxyphenyl group, methylthiophenyl group, phenylthiophenyl group, methylaminophenyl group, dimethylaminophenyl group, acetylaminophenyl group, carboxyphenyl group, methoxycarbonylphenyl group, Ethoxyphenylcarbonyl group, phenoxycarbonylphenyl group, N-phenylcarbamoylphenyl group, nitrophenyl group, cyanophenyl group, sulfophenyl group, sulfonatophenyl group, phosphonophene Group, etc. phosphonophenyl phenyl group.

At least two of R ¹ , R ² and L ¹¹ , or at least two of R ¹ , R ² and L ¹² may be linked to each other to form a ring. At least two of R ³ , R ⁴ and L ²² may be connected to each other to form a ring.
The ring to be formed may have a substituent and may contain a hetero atom (for example, an oxygen atom, a nitrogen atom, or a sulfur atom) as an atom constituting the ring. From the viewpoint of improving developability and stain resistance, and not requiring a complicated synthesis reaction, the cycloalkylene having 3 to 12 carbon atoms which may have a substituent and may contain a hetero atom as a ring constituent atom It is preferably an arylene group having 6 to 12 carbon atoms which may have a hetero atom as a ring constituent atom, and may have a substituent. A cycloalkylene group having 3 to 12 carbon atoms which may contain a hetero atom as a constituent atom is particularly preferable.
Specific examples and preferred examples of the substituent that the ring formed above may have include alkyl groups, aryl groups and their substituents represented by R ¹ , R ² , R ³ , R ⁴ , and R ^5. The thing similar to the specific example and preferable example of these is mentioned.

X ⁺ is preferably -N ⁺ R ¹ R ² -or -S ⁺ R ^1- , and particularly preferably -N ⁺ R ¹ R ^2- .

Formula A in (I) ^- is _{^{-SO 3 -, -CO 2 -,}} -PO 3 H - or -OPO ₃ H ^- represents, in terms of hydrophilicity, preferably, -SO ₃ ^- or -CO ₂ ^-, particularly preferably -SO ₃ ^- it is.

In the general formula (II), the alkyl group and aryl group represented by R ³ , R ^4, or R ⁵ contained in Y ⁺ are described with respect to R ³ , R ⁴ , and R ⁵ , including specific examples thereof. This is the same as the alkyl group and aryl group. As the ring formed by connecting R ³ and R ⁴ to each other, R ³ and R ⁴ each preferably have 1 to 12 carbon atoms from the viewpoint of improving developability and stain resistance and not requiring a complicated synthesis reaction. An alkyl group which may be substituted and an aryl group which may be substituted having 6 to 12 carbon atoms, particularly preferably an alkyl group which may be substituted having 1 to 12 carbon atoms.
Y ⁺ is preferably ^{-N + R 3 R 4 R 5} , -S + R 3 R 4, is ^-I + ^{R 3} or ^{-P + R 3 R 4 R 5} , more preferably ^-N + ^R 3 R ⁴ is R ⁵ or ^-S + ^R 3 ^{R 4,} and most preferably ^{-N + R 3 R 4 R 5} .

In the general formulas (I) and (II), L ¹² and L ²² each independently represent at least one sp ² hybrid orbital or a divalent linking group containing an atom having an sp hybrid orbital, or at least one cyclic Represents a divalent linking group containing an alkylene group.
The atoms having sp ² hybrid orbitals include alkenylene groups (for example, vinylene groups), arylene groups (for example, phenylene groups), carbonyl groups, carbon atoms constituting double bonds such as carbon-nitrogen double bonds, carbonyl groups , Oxygen atoms constituting double bonds such as oxygen-sulfur double bonds, nitrogen atoms constituting double bonds such as carbon-nitrogen double bonds, sulfur constituting double bonds such as oxygen-sulfur double bonds An atom etc. are mentioned.
Examples of the atoms having sp hybrid orbitals include carbon atoms constituting triple bonds such as alkynylene groups (for example, ethynylene groups).
The cyclic alkylene group for L ¹² and L ²² preferably has 3 to 20 carbon atoms, more preferably 3 to 10 carbon atoms, and examples thereof include a cyclopentylene group and a cyclohexylene group.
The divalent linking group represented by L ¹² and L ²² may have a substituent, and the linking group contains a hetero atom (for example, an oxygen atom, a nitrogen atom, or a sulfur atom). Also good.
Specific examples and preferred examples of the substituent that L ¹² and L ²² may have include an alkyl group, an aryl group, and their substituents represented by R ¹ , R ² , R ³ , R ⁴ , and R ^5. The thing similar to the specific example and preferable example of these is mentioned.
The divalent linking group represented by L ¹² or L ²² is preferably a divalent linking group having at least one linking group described in the following group A, B or C, and developability and stain resistance. From the viewpoint of improving properties, it is particularly preferable to have at least one linking group described in the following group A or B, and it is particularly preferable to have at least one linking group described in the following group A.

  In said formula, R represents a C1-C6 alkyl group or a hydroxyl group.

Specific examples of the divalent linking group represented by L ¹² and L ²² are shown below, but the present invention is not limited thereto.

L ¹² in the general formula (I) and L ²² in the general formula (II) are the shortest used for directly linking Y ⁺ to the oxygen atom directly connected to X ⁺ and A ⁻ or L ²² of the phosphate ester. The total number of atoms is preferably from 3 to 20, and preferably from 4 to 12, from the viewpoint of suppressing the approach between the positively charged portion and the negatively charged portion and suppressing the increase in hydrophobicity due to the increase in the linking group. More preferably, it is 4-8.

  The specific polymer compound (A) in the present invention is not particularly limited as long as it is a polymer having a repeating unit (a1) having a partial structure represented by the general formula (I) or (II). Examples of the polymer include (meth) acrylic polymers, styryl polymers, polyurethane resins, polyvinyl alcohol resins, polyvinyl formal resins, polyamide resins, polyester resins, and epoxy resins. In particular, an embodiment of a (meth) acrylic polymer or a styryl polymer is preferable. The repeating unit (a1) having a partial structure represented by the general formula (I) or (II) is preferably a repeating unit represented by the following general formula (A1).

In General Formula (A1), R _{a to} R _c each independently represent a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, or a halogen atom. (Aa1) represents the partial structure represented by the general formula (I) or (II), and is linked to the carbon atom of the main chain at the site represented by 'in the general formula (I) or (II). .

  In the specific polymer compound (A) of the present invention, the proportion of the repeating unit (a1) having a partial structure represented by the general formula (I) or (II) is all repeating units from the viewpoint of stain resistance and developability. Is preferably in the range of 1 to 90 mol%, more preferably in the range of 1 to 70 mol%, and still more preferably in the range of 1 to 60 mol%.

  The specific polymer compound (A) having the repeating unit (a1) according to the present invention can be obtained by polymerizing a radical polymerizable unsaturated group-containing monomer represented by the following general formula (III) or (IV). it can.

In the general formula (III) or (IV), R ^X , R ^Y and R ^Z each independently represent a hydrogen atom or an alkyl group having 1 to 6 carbon atoms.
^{L 11, L 12, L 21} , L 22, X +, A -, and ^{Y + L} in the general formula (I) and ^{(II) 11, L 12,} L 21, L 22, X +, A - , And Y ⁺ .
In addition, this invention relates also to the radically polymerizable unsaturated group containing monomer represented by general formula (III) or (IV).

The radical polymerizable unsaturated group-containing monomer represented by the general formula (III) can be synthesized by using a general Sn2 reaction and a halogen conversion reaction. For example, it can be obtained by reacting a tertiary amine with dibromoalkyl and reacting with sodium sulfite. Moreover, the radically polymerizable unsaturated group-containing monomer represented by the general formula (IV) can be synthesized by using a ring-opening reaction for a dioxaphosphorane compound and then a Sn2 reaction. For example, it can be obtained by a ring-opening reaction of a hydroxy group-containing compound and a chlorooxodioxaphosphorane compound, and then a tertiary amine compound.
Specific examples of the radical polymerizable unsaturated group-containing monomer represented by the general formula (III) or (IV) for obtaining the specific polymer compound (A) having the repeating unit (a1) according to the present invention are shown below. Although shown, this invention is not limited to these.

Furthermore, the specific polymer compound (A) of the present invention contains, as a copolymerization component, a repeating unit (a2) having at least one functional group that interacts with the surface of the support in order to enhance the adhesion to the support. It is preferable. Examples of functional groups that interact with the support surface include, for example, ionic bond formation, hydrogen bond formation, and polar interaction with metals, metal oxides, hydroxyl groups, and the like present on a support that has been anodized or hydrophilized. Groups capable of interacting with each other.
Specific examples of functional groups that interact with the support surface are listed below.

In the above formulas, R ^{11 to} R ¹³ are each independently a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, an alkynyl group having 2 to 10 carbon atoms, an alkenyl group having 2 to 10 carbon atoms, or an alkyl group having 6 to 15 carbon atoms. Represents an aryl group, and M, M ¹ and M ² each independently represent a hydrogen atom, a metal atom contained in an alkali metal or an alkaline earth metal, or an ammonium group.
From the viewpoint of stain resistance and printing durability, the functional group that interacts with the support surface is a group containing the carboxylic acid, a sulfonic acid group, a phosphate ester group or a salt thereof, a phosphonic acid group or a salt thereof. In view of further improving the stain resistance, a phosphoric ester group or a salt thereof, or a phosphonic acid group or a salt thereof is preferable, and a phosphonic acid group or a salt thereof is particularly preferable.

  The repeating unit (a2) having at least one functional group that interacts with the support surface is preferably a repeating unit represented by the following general formula (A2).

In formula _{(A2), R a '~R} c' have the same meanings as _R a to R _c each in the general formula (A1). L ⁴ represents a single bond or a divalent linking group. Q represents a functional group that interacts with the support surface.

The divalent linking group represented by L ⁴ has 1 to 60 carbon atoms, 0 to 10 nitrogen atoms, 0 to 50 oxygen atoms, 1 to 100 hydrogen atoms, and 0 To 20 sulfur atoms are preferred. More specifically, the same as the specific examples and preferred examples of the divalent linking group represented by L ₁ and L ₂ in the general formula (I) or (II) can be given.
Specific examples of the functional group that interacts with the support surface represented by Q include the specific examples described above, and preferred examples are also the same.

  In the specific polymer compound (A) of the present invention, the ratio of the repeating unit (a2) having at least one functional group that interacts with the support surface is 0% of all repeating units from the viewpoint of stain resistance and printing durability. The range is preferably -99 mol%, more preferably 10-95 mol%, and still more preferably 10-90 mol%.

The specific polymer compound (A) of the present invention has at least one repeating unit (a1) having a structure represented by the general formula (I) or (II) and a functional group that interacts with the support surface. A repeating unit other than the repeating unit (a2) (hereinafter also referred to as other repeating unit) may be contained as a copolymerization component. Examples of other repeating units include repeating units derived from various known monomers.
Preferred examples are derived from known monomers such as acrylic esters, methacrylic esters, acrylamides, methacrylamides, vinyl esters, styrenes, acrylic acid, methacrylic acid, acrylonitrile, maleic anhydride, maleic imide, etc. And repeating units. By introducing other repeating units, various physical properties of the layer such as film forming property, film strength, hydrophilicity, hydrophobicity, solubility, reactivity, and stability can be appropriately improved or controlled.

  Specific examples of acrylic esters include methyl acrylate, ethyl acrylate, (n- or i-) propyl acrylate, (n-, i-, sec- or t-) butyl acrylate, amyl acrylate, 2-ethylhexyl acrylate, Dodecyl acrylate, chloroethyl acrylate, 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, 2-hydroxypentyl acrylate, cyclohexyl acrylate, allyl acrylate, trimethylolpropane monoacrylate, pentaerythritol monoacrylate, benzyl acrylate, methoxybenzyl acrylate, chloro Benzyl acrylate, hydroxybenzyl acrylate, hydroxyphenethyl acrylate, dihydroxyphenethyl Acrylate, furfuryl acrylate, tetrahydrofurfuryl acrylate, phenyl acrylate, hydroxyphenyl acrylate, chlorophenyl acrylate, sulfamoylphenyl acrylate, 2- (hydroxyphenyl carbonyloxy) ethyl acrylate, polyalkylene glycol acrylate.

  Specific examples of methacrylic acid esters include methyl methacrylate, ethyl methacrylate, (n- or i-) propyl methacrylate, (n-, i-, sec- or t-) butyl methacrylate, amyl methacrylate, 2-ethylhexyl methacrylate, Dodecyl methacrylate, chloroethyl methacrylate, 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, 2-hydroxypentyl methacrylate, cyclohexyl methacrylate, allyl methacrylate, trimethylolpropane monomethacrylate, pentaerythritol monomethacrylate, benzyl methacrylate, methoxybenzyl methacrylate, chloro Benzyl methacrylate, hydroxybenzyl methacrylate, hydroxyphene Examples include til methacrylate, dihydroxyphenethyl methacrylate, furfuryl methacrylate, tetrahydrofurfuryl methacrylate, phenyl methacrylate, hydroxyphenyl methacrylate, chlorophenyl methacrylate, sulfamoylphenyl methacrylate, 2- (hydroxyphenylcarbonyloxy) ethyl methacrylate, and polyalkylene glycol methacrylate. It is done.

  Specific examples of acrylamides include acrylamide, N-methylacrylamide, N-ethylacrylamide, N-propylacrylamide, N-butylacrylamide, N-benzylacrylamide, N-hydroxyethylacrylamide, N-phenylacrylamide, and N-tolylacrylamide. N- (hydroxyphenyl) acrylamide, N- (sulfamoylphenyl) acrylamide, N- (phenylsulfonyl) acrylamide, N- (tolylsulfonyl) acrylamide, N, N-dimethylacrylamide, N-methyl-N-phenylacrylamide , N-hydroxyethyl-N-methylacrylamide, polyalkylene glycol acrylamide and the like.

  Specific examples of methacrylamides include methacrylamide, N-methylmethacrylamide, N-ethylmethacrylamide, N-propylmethacrylamide, N-butylmethacrylamide, N-benzylmethacrylamide, N-hydroxyethylmethacrylamide, N -Phenylmethacrylamide, N-tolylmethacrylamide, N- (hydroxyphenyl) methacrylamide, N- (sulfamoylphenyl) methacrylamide, N- (phenylsulfonyl) methacrylamide, N- (tolylsulfonyl) methacrylamide, N , N-dimethylmethacrylamide, N-methyl-N-phenylmethacrylamide, N-hydroxyethyl-N-methylmethacrylamide, polyalkylene glycol methacrylamide and the like.

  Specific examples of vinyl esters include vinyl acetate, vinyl butyrate, vinyl benzoate and the like. Specific examples of styrenes include styrene, methyl styrene, dimethyl styrene, trimethyl styrene, ethyl styrene, propyl styrene, cyclohexyl styrene, chloromethyl styrene, trifluoromethyl styrene, ethoxymethyl styrene, acetoxymethyl styrene, methoxy styrene, dimethoxy styrene. Chlorostyrene, dichlorostyrene, bromostyrene, iodostyrene, fluorostyrene, carboxystyrene and the like.

  In the specific polymer compound (A) according to the present invention, the proportion of other repeating units is preferably from 0 to 60 mol%, more preferably from 0 to 40 mol%, still more preferably from 0 to 30%.

  Furthermore, the specific polymer compound (A) in the present invention can be provided with crosslinkability in order to improve the film strength of the image area. In order to give the specific polymer compound (A) crosslinkability, a crosslinkable functional group may be introduced into the main chain or side chain of the polymer compound. The crosslinkable functional group may be introduced by copolymerization or may be introduced by a polymer reaction.

  Here, the crosslinkable functional group is a group having a function of crosslinking the binder polymer in the process of radical polymerization reaction that occurs in the image recording layer when the lithographic printing plate precursor is exposed. Although it will not specifically limit if it is group which has such a function, For example, an ethylenically unsaturated bond group, an epoxy group, etc. are mentioned as a functional group which can be addition-polymerized. Moreover, the functional group which can become a radical by light irradiation may be sufficient, As such a crosslinkable functional group, a thiol group, a halogen group, an onium salt structure etc. are mentioned, for example. Especially, an ethylenically unsaturated bond group is preferable and the functional group represented by the following general formula (i)-(iii) is especially preferable.

In General Formula (i), R ^{1 to} R ³ each independently represent a hydrogen atom or a monovalent organic group. R ¹ is preferably a hydrogen atom or an alkyl group which may have a substituent. Among them, a hydrogen atom or a methyl group is preferable because of high radical reactivity. R ² and R ³ are each independently preferably a hydrogen atom, halogen atom, amino group, carboxyl group, alkoxycarbonyl group, sulfo group, nitro group, cyano group, or optionally substituted alkyl. Group, aryl group which may have a substituent, alkoxy group which may have a substituent, aryloxy group which may have a substituent, alkylamino group which may have a substituent, substituent An arylamino group which may have a substituent, an alkylsulfonyl group which may have a substituent, an arylsulfonyl group which may have a substituent, etc., among them, a hydrogen atom, a carboxyl group, an alkoxycarbonyl group An alkyl group which may have a substituent and an aryl group which may have a substituent are preferable because of high radical reactivity.

X represents an oxygen atom, a sulfur atom, or —N (R ¹² ) —, and R ¹² represents a hydrogen atom or a monovalent organic group. Examples of the monovalent organic group include an alkyl group which may have a substituent. R ¹² is preferably a hydrogen atom, a methyl group, an ethyl group or an isopropyl group because of high radical reactivity.

  Examples of substituents that can be introduced include alkyl groups, alkenyl groups, alkynyl groups, aryl groups, alkoxy groups, aryloxy groups, halogen atoms, amino groups, alkylamino groups, arylamino groups, carboxyl groups, alkoxycarbonyl groups, sulfo groups, A nitro group, a cyano group, an amide group, an alkylsulfonyl group, an arylsulfonyl group and the like can be mentioned.

In General Formula (ii), R ^{4 to} R ⁸ each independently represent a hydrogen atom or a monovalent organic group. R ^{4 to} R ⁸ preferably have a hydrogen atom, a halogen atom, an amino group, a carboxyl group, an alkoxycarbonyl group, a sulfo group, a nitro group, a cyano group, an alkyl group that may have a substituent, or a substituent. An aryl group that may have a substituent, an alkoxy group that may have a substituent, an aryloxy group that may have a substituent, an alkylamino group that may have a substituent, and a substituent. Examples include an arylamino group, an alkylsulfonyl group that may have a substituent, and an arylsulfonyl group that may have a substituent. Among them, a hydrogen atom, a carboxyl group, an alkoxycarbonyl group, and a substituent are included. An alkyl group which may be substituted and an aryl group which may have a substituent are preferred.

Examples of the substituent that can be introduced include the same substituents as those described in formula (i).
Y represents an oxygen atom, a sulfur atom, or —N (R ¹² ) —. R ¹² has the same meaning as ^{R 12} in formula (i), and preferred examples are also the same.

In general formula (iii), R < ⁹ > -R < ¹¹ > represents a hydrogen atom or monovalent organic group each independently. R ⁹ is preferably a hydrogen atom or an alkyl group which may have a substituent. Among them, a hydrogen atom or a methyl group is preferable because of high radical reactivity. R ¹⁰ and R ¹¹ are preferably each independently a hydrogen atom, a halogen atom, an amino group, a carboxyl group, an alkoxycarbonyl group, a sulfo group, a nitro group, a cyano group, an alkyl group which may have a substituent, An aryl group that may have a substituent, an alkoxy group that may have a substituent, an aryloxy group that may have a substituent, an alkylamino group that may have a substituent, and a substituent. An arylamino group which may have a substituent, an alkylsulfonyl group which may have a substituent, an arylsulfonyl group which may have a substituent, and the like. Among them, a hydrogen atom, a carboxyl group, an alkoxycarbonyl group, a substituent An alkyl group which may have a group and an aryl group which may have a substituent are preferable because of high radical reactivity.

Examples of the substituent that can be introduced include the same substituents as those described in formula (i).
Z represents an oxygen atom, a sulfur atom, —N (R ¹³ ) — or a phenylene group which may have a substituent. Examples of R ¹³ include an alkyl group which may have a substituent. Among them, a methyl group, an ethyl group, and an isopropyl group are preferable because of high radical reactivity.

  The specific polymer compound (A) having crosslinkability has, for example, a free radical (a polymerization initiation radical or a growth radical in the polymerization process of the polymerizable compound) added to the crosslinkable functional group, and is directly or polymerizable between the polymers. Addition polymerization is performed through the polymerization chain of the compound, and a crosslink is formed between the polymer molecules to be cured. Alternatively, atoms in the polymer (for example, hydrogen atoms on carbon atoms adjacent to the crosslinkable functional group) are extracted by free radicals to form polymer radicals that are bonded to each other, thereby causing crosslinking between polymer molecules. Forms and cures.

  The specific polymer compound (A) of the present invention can be synthesized by any known method, and a radical polymerization method is preferably used for the synthesis. General radical polymerization methods include, for example, New Polymer Experiments 3, Polymer Synthesis and Reaction 1 (Polymer Society, Kyoritsu Publishing), New Experimental Chemistry Course 19, Polymer Chemistry (I) (The Chemical Society of Japan) , Maruzen), Materials Engineering Course, Synthetic Polymer Chemistry (Tokyo Denki University Press), etc., and these can be applied.

  The mass average molecular weight of the specific polymer compound (A) of the present invention can be arbitrarily set depending on the performance design of the lithographic printing plate precursor. If the mass average molecular weight is too low, the printing durability is lowered. Therefore, the mass average molecular weight is preferably 2,000 to 1,000,000, and more preferably 5,000 to 100 from the viewpoint of printing durability and stain resistance. 7,000, particularly preferably 7,000 to 70,000.

  Specific examples of the specific polymer compound (A) in the present invention are shown below together with their mass average molecular weights, but the present invention is not limited to these. The composition ratio of the polymer structure is expressed in mole percentage. The structure of each repeating unit is represented by a polymerizable component (polymerizable monomer) corresponding to each repeating unit. In the following tables, “molecular weight” represents “mass average molecular weight”.

In the embodiment of the lithographic printing plate precursor according to the invention, the form in which the image recording layer is in contact with the support (first form) and the form in which the image recording layer is different from the layer in contact with the support ( Any of the second forms) is included.
In the case of the second form, a form in which an undercoat layer is directly provided on the support and an image recording layer is provided directly on the undercoat layer is preferable.
The specific polymer compound (A) can be contained in the image recording layer or the undercoat layer by including the specific polymer compound (A) in the image recording layer coating solution or the undercoat layer coating solution. The content of the specific polymer compound (A) (solid content) is preferably from ^{0.1~100mg / m 2, 1~30mg / m} 2 is more preferable.

[Image recording layer]
(B) Polymerization initiator The polymerization initiator (hereinafter also referred to as initiator compound) used in the present invention is contained in the image recording layer. In the present invention, a radical polymerization initiator is preferably used.

  As the initiator compound, those known to those skilled in the art can be used without limitation, and specifically include, for example, trihalomethyl compounds, carbonyl compounds, organic peroxides, azo compounds, azide compounds, metallocene compounds, hexaarylbiphenyls. Examples include imidazole 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 a hexaarylbiimidazole compound, an onium salt compound, a trihalomethyl compound, and a metallocene compound is preferable, and a hexaarylbiimidazole compound and an onium salt compound are particularly preferable. Two or more polymerization initiators may be used in combination as appropriate.

  Examples of the hexaarylbiimidazole compound include lophine dimers described in European Patent No. 24629, European Patent No. 107792, US Pat. No. 4,410,621, such as 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-trifluoro) Methylphenyl) -4,4 ', 5,5'-tetraphenylbiimidazole and the like. The hexaarylbiimidazole compound is particularly preferably used in combination with a sensitizing dye having a maximum absorption in a wavelength region of 300 to 450 nm.

  Examples of onium salts include S.I. I. Schlesinger, Photogr. Sci. Eng. , 18, 387 (1974), T.A. S. Bal et al, Polymer, 21, 423 (1980), diazonium salts described in JP-A-5-158230, ammonium described in US Pat. No. 4,069,055, JP-A-4-365049, and the like. Salt, phosphonium salts described in U.S. Pat. Nos. 4,069,055 and 4,069,056, EP 104,143, U.S. Patent Application Publication No. 2008/0311520 JP-A-2-150848, JP-A-2008-195018, or J.P. V. Crivello et al, Macromolecules, 10 (6), 1307 (1977), iodonium salts, European Patent Nos. 370,693, 233,567, 297,443, 297,442, US Patent 4,933,377, 4,760,013, 4,734,444, 2,833,827, German Patents 2,904,626, 3,604,580, Sulfonium salts described in each specification of JP-A-3,604,581; V. Crivello et al, J.A. Polymer Sci. , Polymer Chem. Ed. , 17, 1047 (1979), a selenonium salt described in C.I. S. Wen et al, Teh, Proc. Conf. Rad. Curing ASIA, p478 Tokyo, Oct (1988), azinium salts described in JP-A-2008-195018, and the like.

  Of these, more preferred are iodonium salts, sulfonium salts, and azinium salts. Although the specific example of these compounds is shown below, it is not limited to this.

  As an example of the iodonium salt, a diphenyl iodonium salt is preferable, and a diphenyl iodonium salt substituted with an electron donating group such as an alkyl group or an alkoxyl group is particularly preferable, and an asymmetric diphenyl iodonium salt is more preferable. Specific examples include diphenyliodonium = hexafluorophosphate, 4-methoxyphenyl-4- (2-methylpropyl) phenyliodonium = hexafluorophosphate, 4- (2-methylpropyl) phenyl-p-tolyliodonium = hexa. Fluorophosphate, 4-hexyloxyphenyl-2,4,6-trimethoxyphenyliodonium = hexafluorophosphate, 4-hexyloxyphenyl-2,4-diethoxyphenyliodonium = tetrafluoroborate, 4-octyloxy Phenyl-2,4,6-trimethoxyphenyliodonium = 1-perfluorobutanesulfonate, 4-octyloxyphenyl-2,4,6-trimethoxyphenyliodonium = hexafluorophosphate, bis ( -t- butylphenyl) iodonium tetraphenylborate and the like.

  Examples of sulfonium salts include triphenylsulfonium = hexafluorophosphate, triphenylsulfonium = benzoylformate, bis (4-chlorophenyl) phenylsulfonium = benzoylformate, bis (4-chlorophenyl) -4-methylphenylsulfonium = Examples thereof include tetrafluoroborate, tris (4-chlorophenyl) sulfonium = 3,5-bis (methoxycarbonyl) benzenesulfonate, and tris (4-chlorophenyl) sulfonium = hexafluorophosphate.

Examples of azinium salts include 1-cyclohexylmethyloxypyridinium = hexafluorophosphate, 1-cyclohexyloxy-4-phenylpyridinium = hexafluorophosphate, 1-ethoxy-4-phenylpyridinium = hexafluorophosphate, 1-cyclohexyl (2-ethylhexyloxy) -4-phenylpyridinium = hexafluorophosphate, 4-chloro-1-cyclohexylmethyloxypyridinium = hexafluorophosphate, 1-ethoxy-4-cyanopyridinium = hexafluorophosphate, 3,4 -Dichloro-1- (2-ethylhexyloxy) pyridinium = hexafluorophosphate, 1-benzyloxy-4-phenylpyridinium = hexafluorophosphate, 1-phenethylo Ci-4-phenylpyridinium = hexafluorophosphate, 1- (2-ethylhexyloxy) -4-phenylpyridinium = p-toluenesulfonate, 1- (2-ethylhexyloxy) -4-phenylpyridinium = perfluorobutanesulfonate 1- (2-ethylhexyloxy) -4-phenylpyridinium bromide, 1- (2-ethylhexyloxy) -4-phenylpyridinium tetrafluoroborate.
The onium salt is particularly preferably used in combination with an infrared absorber having a maximum absorption in a wavelength range of 750 to 1400 nm.

  In addition, polymerization initiators described in paragraph numbers [0071] to [0129] of JP-A-2007-206217 can also be preferably used.

The polymerization initiator is preferably used alone or in combination of two or more.
The content of the polymerization initiator in the image recording layer is preferably 0.01 to 20% by mass, more preferably 0.1 to 15% by mass, and still more preferably 1.0 to 10%, based on the total solid content of the image recording layer. % By mass.

(C) Polymerizable compound The polymerizable compound used in the image recording layer is an addition polymerizable compound having at least one ethylenically unsaturated double bond, and has at least one terminal ethylenically unsaturated bond, preferably 2 It is selected from compounds having at least one. These have chemical forms such as monomers, prepolymers, ie dimers, trimers and oligomers, or 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. Esters of an acid and a polyhydric alcohol compound and amides of an unsaturated carboxylic acid and a polyamine compound are used. In addition, addition reaction products of unsaturated carboxylic acid esters or amides having a nucleophilic substituent such as hydroxyl group, amino group, mercapto group and the like with monofunctional or polyfunctional isocyanates or epoxy, and monofunctional or polyfunctional A dehydration condensation reaction product with a functional carboxylic acid is also preferably used. Further, an unsaturated carboxylic acid ester or amide having an electrophilic substituent such as an isocyanate group or an epoxy group and an addition reaction product of a monofunctional or polyfunctional alcohol, amine or thiol, a halogen group, 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. It is also possible to use a compound group in which the unsaturated carboxylic acid is replaced with unsaturated phosphonic acid, styrene, vinyl ether or the like. These are disclosed in JP-T-2006-508380, JP-A-2002-287344, JP-A-2008-256850, JP-A-2001-342222, JP-A-9-179296, JP-A-9-179297. JP-A-9-179298, JP-A-2004-294935, JP-A-2006-243493, JP-A-2002-275129, JP-A-2003-64130, JP-A-2003-280187, It is described in Japanese Laid-Open Patent Publication No. 10-333321.

  Specific examples of a monomer of an ester of a polyhydric alcohol compound and an unsaturated carboxylic acid include acrylic acid esters such as ethylene glycol diacrylate, 1,3-butanediol diacrylate, tetramethylene glycol diacrylate, propylene glycol diacrylate, Examples include trimethylolpropane triacrylate, hexanediol diacrylate, tetraethylene glycol diacrylate, pentaerythritol tetraacrylate, sorbitol triacrylate, isocyanuric acid ethylene oxide (EO) -modified triacrylate, and polyester acrylate oligomer. Methacrylic acid esters include tetramethylene glycol dimethacrylate, neopentyl glycol dimethacrylate, trimethylolpropane trimethacrylate, ethylene glycol dimethacrylate, pentaerythritol trimethacrylate, bis [p- (3-methacryloxy-2-hydroxypropoxy) phenyl ] Dimethylmethane, bis- [p- (methacryloxyethoxy) phenyl] dimethylmethane, and the like. Specific examples of amide monomers of polyvalent amine compounds and unsaturated carboxylic acids include methylene bis-acrylamide, methylene bis-methacrylamide, 1,6-hexamethylene bis-acrylamide, 1,6-hexamethylene bis-methacrylic. Examples include amide, diethylenetriamine trisacrylamide, xylylene bisacrylamide, and xylylene bismethacrylamide.

  Further, urethane-based addition polymerizable compounds produced by using an addition reaction of isocyanate and hydroxyl group are also suitable. Specific examples thereof include, for example, one molecule described in JP-B-48-41708. A vinylurethane compound containing two or more polymerizable vinyl groups in one molecule obtained by adding a vinyl monomer containing a hydroxyl group represented by the following general formula (A) to a polyisocyanate compound having two or more isocyanate groups Etc.

_{CH 2 = C (R 4)} COOCH 2 CH (R 5) OH (A)
(However, R ₄ and R ₅ represent H or CH _3. )

  Also, urethanes described in JP-A-51-37193, JP-B-2-32293, JP-B-2-16765, JP-A-2003-344997, and JP-A-2006-65210. Acrylates, JP-B 58-49860, JP-B 56-17654, JP-B 62-39417, JP-B 62-39418, JP-A 2000-250211, JP-A 2007-94138 Urethane compounds having an ethylene oxide skeleton described in the publication, US Pat. No. 7,153,632, JP-T 8-505958, JP-A 2007-293221, and JP-A 2007-293223. Urethane compounds having the described hydrophilic group are also suitable.

  Among the above, in the case of a lithographic printing plate precursor to which on-press development is applied, tris (acryloyloxyethyl) isocyanate is excellent in that it has a good balance of hydrophilicity involved in on-press developability and polymerization ability involved in printing durability. Isocyanuric acid ethylene oxide-modified acrylates such as nurate and bis (acryloyloxyethyl) hydroxyethyl isocyanurate are particularly preferred.

  Details of the method of use, such as the structure of the polymerizable compound, whether it is used alone or in combination, and the amount added, can be arbitrarily set according to the performance design of the final lithographic printing plate precursor. The polymerizable compound is preferably used in the range of 5 to 75% by mass, more preferably 25 to 70% by mass, and particularly preferably 30 to 60% by mass with respect to the total solid content of the image recording layer.

(D) Sensitizing dye The sensitizing dye used in the image recording layer absorbs light at the time of image exposure to an excited state, supplies energy to the polymerization initiator by electron transfer, energy transfer or heat generation, and initiates polymerization. Any device that improves the function can be used without particular limitation. In particular, a sensitizing dye having a maximum absorption in a wavelength range of 300 to 450 nm or 750 to 1400 nm is preferably used.

  Examples of the sensitizing dye having maximum absorption in the wavelength range of 300 to 450 nm include merocyanines, benzopyrans, coumarins, aromatic ketones, anthracenes, styryls, oxazoles and the like.

  Of the sensitizing dyes having an absorption maximum in the wavelength range of 300 to 450 nm, a dye more preferable from the viewpoint of high sensitivity is a dye represented by the following general formula (IX).

In General Formula (IX), A represents an aryl group or a heteroaryl 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 represents a monovalent non-metallic atomic group, and A and R ₁ or R ₂ and R ₃ are bonded to each other to form an aliphatic or aromatic group. A ring may be formed.

General formula (IX) will be described in more detail. The monovalent nonmetallic atomic group represented by R ₁ , R ₂ or R ₃ is preferably a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted aryl group. Represents a substituted or unsubstituted heteroaryl group, a substituted or unsubstituted alkoxy group, a substituted or unsubstituted alkylthio group, a hydroxyl group, or a halogen atom.

The aryl group and heteroaryl group which may have a substituent represented by A are a substituted or unsubstituted aryl group and a substituted or unsubstituted heteroaryl group represented by R ₁ , R ₂ and R ₃ , respectively. It is the same.

Specific examples of such a sensitizing dye include paragraph numbers [0047] to [0053] of JP-A No. 2007-58170, paragraph numbers [0036] to [0037] of JP-A No. 2007-93866, and JP-A No. 2007-. The compounds described in paragraph Nos. [0042] to [0047] of No. 72816 are preferably used.

  JP-A-2006-189604, JP-A-2007-171406, JP-A-2007-206216, JP-A-2007-206217, JP-A-2007-225701, JP-A-2007-225702, JP-A-2007-316582 Sensitizing dyes described in JP-A-2007-328243 can also be preferably used.

  Then, it describes about the sensitizing dye (henceforth an infrared absorber) which has maximum absorption in the wavelength range of 750-1400 nm. As the infrared absorber, a dye or a pigment is preferably used.

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 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 general formula (a).

In general formula (a), X ¹ represents a hydrogen atom, a halogen atom, —NPh ₂ , —X ² -L ¹ or a group shown below. Here, 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 aryl group having a hetero atom (N, S, O, halogen atom, Se), The C1-C12 hydrocarbon group containing a hetero atom is shown. X _a ⁻ has the same meaning as Z _a ⁻ described later. R ^a represents a hydrogen atom or a substituent selected from an alkyl group, an aryl group, a substituted or unsubstituted amino group, and a halogen atom.

R ¹ and R ² each independently represent a hydrocarbon group having 1 to 12 carbon atoms. In view of storage stability of the image recording layer coating solution, R ¹ and R ² are preferably hydrocarbon groups having 2 or more carbon atoms. R ¹ and R ² may be connected to each other to form a ring, and when a ring is formed, it is particularly preferable to form a 5-membered ring or a 6-membered ring.

Ar ¹ and Ar ² may be the same or different and each represents an aryl group which may have a substituent. Preferred aryl groups include a benzene ring group and a naphthalene ring group. 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. In view of easy availability of the raw material, a hydrogen atom is preferred. 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. Preferred Z _a ⁻ is a halide ion, a perchlorate ion, a tetrafluoroborate ion, a hexafluorophosphate ion, and a sulfonate ion, particularly preferably a perchlorate ion, from the storage stability of the image recording layer coating solution. , Hexafluorophosphate ions and aryl sulfonate ions.

  Specific examples of the cyanine dye represented by the general formula (a) include compounds described in paragraph Nos. [0017] to [0019] of JP-A No. 2001-133969, paragraph Nos. [0016] of JP-A No. 2002-023360, [0021], compounds described in paragraphs [0012] to [0037] of JP-A No. 2002-040638, preferably paragraphs [0034] to [0041] of JP-A No. 2002-278057, JP-A No. 2008-195018 And the compounds described in paragraphs [0035] to [0043] of JP-A-2007-90850 are particularly preferable.

  In addition, compounds described in paragraph numbers [0008] to [0009] of JP-A No. 5-5005 and paragraph numbers [0022] to [0025] of JP-A No. 2001-222101 can also be preferably used.

  Only 1 type may be used for an infrared absorption dye, 2 or more types may be used together, and infrared absorbers other than infrared absorption dyes, such as a pigment, may be used together. As the pigment, the compounds described in JP-A-2008-195018, paragraphs [0072] to [0076] are preferable.

  The content of the sensitizing dye is preferably 0.05 to 30 parts by mass, more preferably 0.1 to 20 parts by mass, and particularly preferably 0.2 to 10 parts by mass with respect to 100 parts by mass of the total solid content of the image recording layer. Part by mass.

(E) Binder polymer As the binder polymer contained in the image recording layer of the present invention, those capable of supporting the image recording layer components on a support and removable with a developer are used. As the binder polymer, (meth) acrylic polymer, polyurethane resin, polyvinyl alcohol resin, polyvinyl butyral resin, polyvinyl formal resin, polyamide resin, polyester resin, epoxy resin and the like are used. In particular, (meth) acrylic polymers, polyurethane resins, and polyvinyl butyral resins are preferably used, and (meth) acrylic polymers, polyurethane resins, and polyvinyl butyral resins are more preferable.

In the present invention, “(meth) acrylic polymer” means (meth) acrylic acid, (meth) acrylic acid ester (alkyl ester, aryl ester, allyl ester, etc.), (meth) acrylamide and (meth) acrylamide derivatives. This refers to a copolymer having a (meth) acrylic acid derivative as a polymerization component. “Polyurethane resin” refers to a polymer produced by a condensation reaction of a compound having two or more isocyanate groups and a compound having two or more hydroxyl groups. “Polyvinyl butyral resin” refers to a polymer synthesized by reacting polyvinyl alcohol and butyraldehyde obtained by saponifying part or all of polyvinyl acetate under an acidic condition (acetalization reaction). A polymer having an acid group or the like introduced by a method of reacting a compound having a remaining hydroxy group and an acid group or the like is also included.
A suitable example of the (meth) acrylic polymer in the present invention includes a copolymer having a repeating unit containing an acid group. Examples of the acid group include a carboxylic acid group, a sulfonic acid group, a phosphonic acid group, a phosphoric acid group, and a sulfonamide group, and a carboxylic acid group is particularly preferable. As the repeating unit containing an acid group, a repeating unit derived from (meth) acrylic acid or one represented by the following general formula (I) is preferably used.

In general formula (I), R ¹ represents a hydrogen atom or a methyl group, and R ² represents a single bond or an n + 1 valent linking group. A represents an oxygen atom or —NR ³ —, and R ³ represents a hydrogen atom or a monovalent hydrocarbon group having 1 to 10 carbon atoms. n represents an integer of 1 to 5.

The linking group represented by R ² in the general formula (I) is composed of a hydrogen atom, a carbon atom, an oxygen atom, a nitrogen atom, a sulfur atom and a halogen atom, and the number of atoms is preferably 1 to 80. is there. Specifically, an alkylene group, a substituted alkylene group, an arylene group, a substituted arylene group, and the like can be mentioned. These divalent groups are linked in multiples by any of an amide bond, an ether bond, a urethane bond, a urea bond, and an ester bond. You may have the structure made. R ² has a structure in which a single bond, an alkylene group, a substituted alkylene group, and an alkylene group and / or a substituted alkylene group are connected by a plurality of amide bonds, ether bonds, urethane bonds, urea bonds, or ester bonds. A single bond, an alkylene group having 1 to 5 carbon atoms, a substituted alkylene group having 1 to 5 carbon atoms and an alkylene group having 1 to 5 carbon atoms and / or a substituted alkylene group having 1 to 5 carbon atoms is an amide bond, an ether More preferably, it is a structure in which a plurality of bonds, urethane bonds, urea bonds, or ester bonds are connected, and a single bond, an alkylene group having 1 to 3 carbon atoms, a substituted alkylene group having 1 to 3 carbon atoms, and carbon. An alkylene group of 1 to 3 and / or a substituted alkylene group of 1 to 3 carbon atoms is an amide bond, ether bond, urethane bond, urea bond, It is particularly preferable that the structure is a structure in which a plurality of ter bonds are connected.
Examples of the substituent include a monovalent non-metallic atomic group excluding a hydrogen atom, a halogen atom (—F, —Br, —Cl, —I), a hydroxyl group, a cyano group, an alkoxy group, an aryloxy group, Examples include a mercapto group, an alkylthio group, an arylthio group, an alkylcarbonyl group, an arylcarbonyl group, a carboxyl group and its conjugate base group, an alkoxycarbonyl group, an aryloxycarbonyl group, a carbamoyl group, an aryl group, an alkenyl group, and an alkynyl group.

R ³ is preferably a hydrogen atom or a hydrocarbon group having 1 to 5 carbon atoms, more preferably a hydrogen atom or a hydrocarbon group having 1 to 3 carbon atoms, and particularly preferably a hydrogen atom or a methyl group. n is preferably 1 to 3, more preferably 1 or 2, and particularly preferably 1.

The proportion (mol%) of the polymerization component having a carboxylic acid group in the total polymerization components of the (meth) acrylic polymer is preferably 1 to 70% from the viewpoint of developability. Considering compatibility between developability and printing durability, 1 to 50% is more preferable, and 1 to 30% is particularly preferable.
The (meth) acrylic polymer used in the present invention preferably further has a crosslinkable group. Here, the crosslinkable group is a group that crosslinks the binder polymer in the process of radical polymerization reaction that occurs in the image recording layer when the lithographic printing plate precursor is exposed. Although it will not specifically limit if it is a group of such a function, For example, an ethylenically unsaturated bond group, an amino group, an epoxy group etc. are mentioned as a functional group which can be addition-polymerized. Moreover, the functional group which can become a radical by light irradiation may be sufficient, As such a crosslinkable group, a thiol group, a halogen group, etc. are mentioned, for example. Of these, an ethylenically unsaturated bond group is preferable. As the ethylenically unsaturated bond group, a styryl group, a (meth) acryloyl group, and an allyl group are preferable.

  In the binder polymer, for example, free radicals (polymerization initiating radicals or growth radicals in the polymerization process of the polymerizable compound) are added to the crosslinkable functional group, and the addition polymerization is performed directly between the polymers or through the polymerization chain of the polymerizable compound. As a result, a cross-link is formed between the polymer molecules and cured. Alternatively, atoms in the polymer (eg, hydrogen atoms on carbon atoms adjacent to the functional bridging group) are abstracted by free radicals to form polymer radicals that are bonded together, thereby causing cross-linking between polymer molecules. Forms and cures.

  The content of the crosslinkable group in the (meth) acrylic polymer (content of unsaturated double bond capable of radical polymerization by iodine titration) is preferably 0.01 to 10.0 mmol per 1 g of the binder polymer. Preferably it is 0.05-9.0 mmol, Most preferably, it is 0.1-8.0 mmol.

  The (meth) acrylic polymer used in the present invention includes, in addition to the above-described polymer unit having an acid group and polymer unit having a crosslinkable group, a polymer unit of (meth) acrylic acid alkyl or aralkyl ester, (meth) acrylamide. Alternatively, it may have a polymer unit of a derivative thereof, a polymer unit of α-hydroxymethyl acrylate, or a polymer unit of a styrene derivative. The alkyl group of the (meth) acrylic acid alkyl ester is preferably an alkyl group having 1 to 5 carbon atoms and an alkyl group having the aforementioned substituent having 2 to 8 carbon atoms, and a methyl group is more preferable. Examples of the (meth) acrylic acid aralkyl ester include benzyl (meth) acrylate. Examples of (meth) acrylamide derivatives include N-isopropylacrylamide, N-phenylmethacrylamide, N- (4-methoxycarbonylphenyl) methacrylamide, N, N-dimethylacrylamide, morpholinoacrylamide and the like. Examples of the α-hydroxymethyl acrylate include ethyl α-hydroxymethyl acrylate and cyclohexyl α-hydroxymethyl acrylate. Examples of styrene derivatives include styrene and 4-tertbutylstyrene.

  In the case of a lithographic printing plate precursor to which on-press development is applied, the binder polymer preferably has a hydrophilic group. The hydrophilic group contributes to imparting on-press developability to the image recording layer. In particular, the coexistence of the crosslinkable group and the hydrophilic group makes it possible to achieve both printing durability and on-press developability.

  Examples of the hydrophilic group include a hydroxy group, a carboxyl group, an alkylene oxide structure, an amino group, an ammonium group, an amide group, a sulfo group, and a phosphoric acid group. Among them, an alkylene oxide unit having 2 or 3 carbon atoms An alkylene oxide structure having 1 to 9 is preferable. For imparting a hydrophilic group to the binder polymer, for example, copolymerization of a monomer having a hydrophilic group is performed.

  As preferable examples of the polyurethane resin in the present invention, paragraph numbers [00099] to [0210] of JP-A No. 2007-187836, paragraph numbers [0019] to [0100] of JP-A No. 2008-276155, JP-A No. 2005-2005, Examples thereof include polyurethane resins described in paragraph numbers [0018] to [0107] of No. 250438 and paragraph numbers [0021] to [0083] of JP-A No. 2005-250158.

Preferable examples of the polyvinyl butyral resin in the present invention include polyvinyl butyral resins described in paragraph numbers [0006] to [0013] of JP-A-2001-75279.
A part of the acid groups in the binder polymer may be neutralized with a basic compound. Examples of basic compounds include compounds containing basic nitrogen, alkali metal hydroxides, and quaternary ammonium salts of alkali metals.

The binder polymer has a mass average molecular weight of preferably 5,000 or more, more preferably 10,000 to 300,000, a number average molecular weight of 1,000 or more, and more preferably 2,000 to 250,000. The polydispersity (mass average molecular weight / number average molecular weight) is preferably 1.1 to 10.
A binder polymer may be used independently or may be used in mixture of 2 or more types.
The content of the binder polymer is preferably 5 to 75% by mass, more preferably 10 to 70% by mass with respect to the total solid content of the image recording layer, from the viewpoint of good image area strength and image formability. -60 mass% is still more preferable.
The total content of the polymerizable compound and the binder polymer is preferably 90% by mass or less with respect to the total solid content of the image recording layer. If it exceeds 90% by mass, the sensitivity and developability may be lowered. More preferably, it is 35-80 mass%.

(F) Low molecular weight hydrophilic compound The image-recording layer in the invention may contain a low molecular weight hydrophilic compound in order to improve the on-press developability without reducing the 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, Polyols such as pentaerythritol and tris (2-hydroxyethyl) isocyanurate, organic amines such as triethanolamine, diethanolamine and monoethanolamine and salts thereof, organic sulfones such as alkylsulfonic acid, toluenesulfonic acid and benzenesulfonic acid Acids and salts thereof, organic sulfamic acids such as alkylsulfamic acid and salts thereof, organic sulfuric acids such as alkylsulfuric acid and alkylethersulfuric acid and salts thereof, phenylphosphonic acid Organic phosphonic acids and salts thereof, tartaric acid, oxalic acid, citric acid, malic acid, lactic acid, gluconic acid, organic carboxylic acids and salts thereof such as amino acids, betaines, and the like.

  Among these, in the present invention, it is preferable to contain at least one selected from polyols, organic sulfates, organic sulfonates, and betaines.

  Specific examples of organic sulfonates include alkyl sulfonates such as sodium n-butyl sulfonate, sodium n-hexyl sulfonate, sodium 2-ethylhexyl sulfonate, sodium cyclohexyl sulfonate, and sodium n-octyl sulfonate. Sodium 5,8,11-trioxapentadecane-1-sulfonate, sodium 5,8,11-trioxaheptadecane-1-sulfonate, 13-ethyl-5,8,11-trioxaheptadecane-1; Alkyl sulfonates containing ethylene oxide chains such as sodium sulfonate, 5,8,11,14-tetraoxatetradecosane-1-sodium sulfonate; sodium benzenesulfonate, sodium p-toluenesulfonate, p-hydroxy Benzenesulfo Acid sodium, sodium p-styrenesulfonate, sodium dimethyl-5-sulfonate isophthalate, sodium 1-naphthylsulfonate, sodium 4-hydroxynaphthylsulfonate, disodium 1,5-naphthalenedisulfonate, 1,3,6 -Aryl sulfonates such as trisodium naphthalene trisulfonate, Paragraph Nos. [0026] to [0031] of JP-A No. 2007-276454, Paragraph Nos. [0020] to [0047] of JP-A No. 2009-154525 Compound etc. are mentioned. The salt may be a potassium salt or a lithium salt.

  Organic sulfates include sulfates of alkyl, alkenyl, alkynyl, aryl or heterocyclic monoethers of polyethylene oxide. The number of ethylene oxide units is preferably 1 to 4, and the salt is preferably a sodium salt, potassium salt or lithium salt. Specific examples thereof include compounds described in paragraph numbers [0034] to [0038] of JP-A-2007-276454.

  As the betaines, compounds having 1 to 5 carbon atoms of the hydrocarbon substituent on the nitrogen atom are preferable. Specific examples include trimethylammonium acetate, dimethylpropylammonium acetate, 3-hydroxy-4-trimethyl. Ammonioobylate, 4- (1-pyridinio) butyrate, 1-hydroxyethyl-1-imidazolioacetate, trimethylammonium methanesulfonate, dimethylpropylammonium methanesulfonate, 3-trimethylammonio-1-propanesulfonate, Examples include 3- (1-pyridinio) -1-propanesulfonate.

  Since low molecular weight hydrophilic compounds have a small hydrophobic part structure and almost no surface activity, dampening water penetrates into the exposed part of the image recording layer (image part), reducing the hydrophobicity and film strength of the image part. The ink receptivity and printing durability of the image recording layer can be maintained well.

  The content of the low molecular weight hydrophilic compound in the image recording layer is preferably 0.5 to 20% by mass, more preferably 1 to 15% by mass, and further preferably 2 to 10% by mass with respect to the total solid content of the image recording layer. preferable. In this range, good on-press developability and printing durability can be obtained. A low molecular weight hydrophilic compound may be used independently and may be used in mixture of 2 or more types.

(G) Grease-sensitizing agent The image-recording layer of the invention may contain a oil-sensitizing agent such as a phosphonium compound, a nitrogen-containing low molecular weight compound, or an ammonium group-containing polymer in order to improve the inking property. . In particular, when the protective layer contains an inorganic stratiform compound, the sensitizer functions as a surface coating agent for the inorganic stratiform compound, and prevents a decrease in the inking property during printing by the inorganic stratiform compound.

  Suitable phosphonium compounds include phosphonium compounds described in JP-A-2006-297907 and JP-A-2007-50660. Specific examples include tetrabutylphosphonium iodide, butyltriphenylphosphonium bromide, tetraphenylphosphonium bromide, 1,4-bis (triphenylphosphonio) butanedi (hexafluorophosphate), 1,7-bis (tri Phenylphosphonio) heptane sulfate, 1,9-bis (triphenylphosphonio) nonane = naphthalene-2,7-disulfonate, and the like.

  Examples of the nitrogen-containing low molecular weight compound include amine salts and quaternary ammonium salts. Also included are imidazolinium salts, benzoimidazolinium salts, pyridinium salts, and quinolinium salts. Of these, quaternary ammonium salts and pyridinium salts are preferred. Specific examples include tetramethylammonium = hexafluorophosphate, tetrabutylammonium = hexafluorophosphate, dodecyltrimethylammonium = p-toluenesulfonate, benzyltriethylammonium = hexafluorophosphate, benzyldimethyloctylammonium = hexafluorophosphate. Fert, benzyldimethyldodecyl ammonium = hexafluorophosphate, compounds described in JP-A No. 2008-284858, paragraph numbers [0021] to [0037], JP-A No. 2009-90645, paragraphs [0030] to [0057], etc. Is mentioned.

  The ammonium group-containing polymer may be any polymer as long as it has an ammonium group in its structure, but a polymer containing 5 to 80 mol% of (meth) acrylate having an ammonium group in the side chain as a copolymerization component is preferable. Specific examples include the polymers described in paragraph numbers [0089] to [0105] of JP-A-2009-208458.

  The ammonium salt-containing polymer preferably has a reduced specific viscosity (unit: ml / g) determined by the following measurement method in the range of 5 to 120, more preferably in the range of 10 to 110, and 15 to 15 Those in the range of 100 are particularly preferred. When the said reduced specific viscosity is converted into a mass average molecular weight, 10,000-150,000 are preferable, 17000-140000 are more preferable, 20000-130000 are especially preferable.

<Measurement method of reduced specific viscosity>
Weigh 3.33 g of 30% polymer solution (1 g as solid content) into a 20 ml volumetric flask and make up with N-methylpyrrolidone. This solution is allowed to stand for 30 minutes in a constant temperature bath at 30 ° C., put in an Ubbelohde reduced viscosity tube (viscosity constant = 0.010 cSt / s), and the time for flowing down at 30 ° C. is measured. The measurement is performed twice with the same sample, and the average value is calculated. Similarly, in the case of a blank (only N-methylpyrrolidone), the reduced specific viscosity (ml / g) is calculated from the following formula.

Specific examples of the ammonium group-containing polymer are shown below.
(1) 2- (trimethylammonio) ethyl methacrylate = p-toluenesulfonate / 3,6-dioxaheptyl methacrylate copolymer (molar ratio 10/90 mass average molecular weight 45,000)
(2) 2- (Trimethylammonio) ethyl methacrylate = hexafluorophosphate / 3,6-dioxaheptyl methacrylate copolymer (molar ratio 20/80 mass average molecular weight 60,000)
(3) 2- (Ethyldimethylammonio) ethyl methacrylate = p-toluenesulfonate / hexyl methacrylate copolymer (molar ratio 30/70 mass average molecular weight 45,000)
(4) 2- (trimethylammonio) ethyl methacrylate = hexafluorophosphate / 2-ethylhexyl methacrylate copolymer (molar ratio 20/80 mass average molecular weight 60,000)
(5) 2- (Trimethylammonio) ethyl methacrylate = methyl sulfate / hexyl methacrylate copolymer (molar ratio 40/60 mass average molecular weight 7 million)
(6) 2- (butyldimethylammonio) ethyl methacrylate = hexafluorophosphate / 3,6-dioxaheptyl methacrylate copolymer (molar ratio 25/75 mass average molecular weight 650,000)
(7) 2- (Butyldimethylammonio) ethyl acrylate = hexafluorophosphate / 3,6-dioxaheptyl methacrylate copolymer (molar ratio 20/80 mass average molecular weight 650,000)
(8) 2- (butyldimethylammonio) ethyl methacrylate = 13-ethyl-5,8,11-trioxa-1-heptadecanesulfonate / 3,6-dioxaheptyl methacrylate copolymer (molar ratio 20/80 (Mass average molecular weight 75,000)
(9) 2- (butyldimethylammonio) ethyl methacrylate = hexafluorophosphate / 3,6-dioxaheptyl methacrylate / 2-hydroxy-3-methacryloyloxypropyl methacrylate copolymer (molar ratio 15/80/5 (Mass average molecular weight 650,000)

  The content of the sensitizer is preferably 0.01 to 30.0% by mass, more preferably 0.1 to 15.0% by mass, and 1 to 5% by mass with respect to the total solid content of the image recording layer. Further preferred.

(H) Hydrophobized precursor The image-recording layer can contain a hydrophobized precursor in order to improve the on-press developability. The hydrophobized precursor means fine particles capable of converting the image recording layer to hydrophobic when heat is applied. The fine particles are at least one selected from hydrophobic thermoplastic polymer fine particles, heat-reactive polymer fine particles, polymer fine particles having a polymerizable group, microcapsules enclosing a hydrophobic compound, and microgel (crosslinked polymer fine particles). It is preferable. Among these, polymer fine particles and microgels having a polymerizable group are preferable.

Hydrophobic thermoplastic polymer fine particles include those disclosed in Research Disclosure, No. 1, January 1992. 333003, JP-A-9-123387, JP-A-9-131850, JP-A-9-171249, JP-A-9-171250, and European Patent No. 931647, etc. A fine particle can be mentioned as a suitable thing.
Specific examples of polymers constituting such polymer fine particles include ethylene, styrene, vinyl chloride, methyl acrylate, ethyl acrylate, methyl methacrylate, ethyl methacrylate, vinylidene chloride, acrylonitrile, vinyl carbazole, and polyalkylene structures. Mention may be made of homopolymers or copolymers of monomers such as acrylates or methacrylates or mixtures thereof. Among them, more preferable examples include a copolymer containing polystyrene, styrene and acrylonitrile, and polymethyl methacrylate.

  The average particle diameter of the hydrophobic thermoplastic polymer fine particles used in the present invention is preferably 0.01 to 2.0 μm.

  Examples of the heat-reactive polymer fine particles used in the present invention include polymer fine particles having a heat-reactive group, and these form a hydrophobized region by cross-linking by a heat reaction and a functional group change at that time.

  The thermoreactive group in the polymer fine particles having a thermoreactive group used in the present invention may be any functional group that performs any reaction as long as a chemical bond is formed, but is preferably a polymerizable group, Examples include ethylenically unsaturated groups that undergo radical polymerization reactions (eg, acryloyl groups, methacryloyl groups, vinyl groups, allyl groups, etc.), cationic polymerizable groups (eg, vinyl groups, vinyloxy groups, epoxy groups, oxetanyl groups, etc.) ), An isocyanato group that performs an addition reaction or a block thereof, an epoxy group, a vinyloxy group, and a functional group having an active hydrogen atom that is a reaction partner thereof (for example, an amino group, a hydroxy group, a carboxy group, etc.), and a condensation reaction Carboxy group and reaction partner hydroxy group or amino group, acid anhydride and reaction phase for ring-opening addition reaction , And the like as a preferable amino group or a hydroxy group is.

  As the microcapsules used in the present invention, for example, as described in JP-A Nos. 2001-277740 and 2001-277742, all or part of the constituent components of the image recording layer are encapsulated in the microcapsules. Is. The constituent components of the image recording layer can also be contained outside the microcapsules. Furthermore, the image recording layer containing microcapsules is preferably a mode in which hydrophobic constituent components are encapsulated in microcapsules and hydrophilic constituent components are contained outside the microcapsules.

  The microgel used in the present invention can contain a part of the constituent components of the image recording layer in at least one of the inside and the surface thereof. In particular, an embodiment in which a reactive microgel is formed by having a radical polymerizable group on the surface thereof is particularly preferable from the viewpoint of image forming sensitivity and printing durability.

  A known method can be applied to microencapsulate or microgel the constituents of the image recording layer.

  The average particle size of the microcapsule or microgel is preferably 0.01 to 3.0 μm, more preferably 0.05 to 2.0 μm, and particularly preferably 0.10 to 1.0 μm. Within this range, good resolution and stability over time can be obtained.

  The content of the hydrophobizing precursor is preferably 5 to 90% by mass based on the total solid content of the image recording layer.

(I) Other image recording layer components The image recording layer preferably contains a chain transfer agent. The chain transfer agent is defined, for example, in Polymer Dictionary 3rd Edition (edited by Polymer Society, 2005) pages 683-684. As the chain transfer agent, for example, a compound group having SH, PH, SiH, GeH in the molecule is used. These can donate hydrogen to low-activity radical species to generate radicals, or can be oxidized and then deprotonated to generate radicals. In the image recording layer of the present invention, in particular, thiol compounds (for example, 2-mercaptobenzimidazoles, 2-mercaptobenzthiazoles, 2-mercaptobenzoxazoles, 3-mercaptotriazoles, 5-mercaptotetrazoles, etc.) Can be preferably used.

  The content of the chain transfer agent is preferably 0.01 to 20 parts by mass, more preferably 1 to 10 parts by mass, and particularly preferably 1 to 5 parts by mass with respect to 100 parts by mass of the total solid content of the image recording layer. is there.

  The image recording layer can further contain various additives as required. Additives include surfactants for promoting developability and improving the surface of the coating, hydrophilic polymers for improving developability and dispersion stability of microcapsules, and visual and non-image areas visible Colorants and print-out agents for polymerization, polymerization inhibitors for preventing unnecessary thermal polymerization of polymerizable compounds during production or storage of the image recording layer, higher fatty derivatives for preventing polymerization inhibition by oxygen, etc. Hydrophobic low molecular weight compounds, inorganic fine particles for improving the strength of the cured film in the image area, organic fine particles, co-sensitizers for improving sensitivity, plasticizers for improving plasticity, and the like. All of these compounds are known, for example, paragraph numbers [0161] to [0215] of JP-A-2007-206217, paragraph number [0067] of JP-T-2005-509192, paragraphs of JP-A-2004-310000. The compounds described in the numbers [0023] to [0026] and [0059] to [0066] can be used. As for the surfactant, a surfactant which may be added to the developer described later can also be used.

<Formation of image recording layer>
The image recording layer of the present invention is formed by preparing and applying a coating solution by dispersing or dissolving each of the necessary image recording layer components in a solvent. Examples of the solvent used include methyl ethyl ketone, ethylene glycol monomethyl ether, 1-methoxy-2-propanol, 2-methoxyethyl acetate, 1-methoxy-2-propyl acetate, and γ-butyllactone. It is not limited. A solvent is used individually or in mixture. The solid content concentration of the coating solution is preferably 1 to 50% by mass.

The coating amount (solid content) of the image recording layer is preferably 0.3 to 3.0 g / m ² . 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]
In the lithographic printing plate precursor according to the invention, a protective layer (oxygen blocking layer) is preferably provided on the image recording layer in order to block diffusion and penetration of oxygen that hinders the polymerization reaction during exposure. As a material for the protective layer, either a water-soluble polymer or a water-insoluble polymer can be appropriately selected and used, and two or more kinds can be mixed and used as necessary. Specific examples include polyvinyl alcohol, modified polyvinyl alcohol, polyvinyl pyrrolidone, water-soluble cellulose derivatives, poly (meth) acrylonitrile, and the like. Among these, it is preferable to use a water-soluble polymer compound having relatively excellent crystallinity. Specifically, using polyvinyl alcohol as a main component gives particularly good results in terms of basic characteristics such as oxygen barrier properties and development removability.

  The polyvinyl alcohol used for the protective layer may be partially substituted with an ester, an ether or an acetal as long as it contains the unsubstituted vinyl alcohol unit necessary for having the necessary oxygen barrier properties and water solubility. Similarly, some of them may have other copolymer components. Polyvinyl alcohol is obtained by hydrolyzing polyvinyl acetate. Specific examples of polyvinyl alcohol include those having a hydrolysis degree of 69.0 to 100 mol% and a number of polymerization repeating units in the range of 300 to 2400. Specifically, PVA-102, PVA-103, PVA-105, PVA-110, PVA-117, PVA-117H, PVA-120, PVA-124, PVA-124H, PVA-CS, manufactured by Kuraray Co., Ltd. PVA-CST, PVA-HC, PVA-203, PVA-204, PVA-205, PVA-210, PVA-217, PVA-220, PVA-224, PVA-235, PVA-217EE, PVA-217E, PVA- 220E, PVA-224E, PVA-403, PVA-405, PVA-420, PVA-424H, PVA-505, PVA-617, PVA-613, PVA-706, L-8 and the like. Polyvinyl alcohol can be used alone or in combination. Content in the protective layer of polyvinyl alcohol becomes like this. Preferably it is 20-95 mass%, More preferably, it is 30-90 mass%.

  Also, modified polyvinyl alcohol can be preferably used. In particular, acid-modified polyvinyl alcohol having a carboxylic acid group or a sulfonic acid group is preferably used. Specific examples include polyvinyl alcohols described in JP-A-2005-250216 and JP-A-2006-259137.

  In the case of using a mixture of polyvinyl alcohol and other materials, as a component to be mixed, modified polyvinyl alcohol, polyvinyl pyrrolidone or a modified product thereof is preferable from the viewpoint of oxygen-blocking property and development removability, and its content in the protective layer Is 3.5 to 80% by mass, preferably 10 to 60% by mass, and more preferably 15 to 30% by mass.

  The protective layer can be provided with flexibility by adding glycerin, dipropylene glycol or the like in an amount corresponding to several mass% with respect to the polymer. In addition, anionic surfactants such as sodium alkyl sulfate and sodium alkyl sulfonate, amphoteric surfactants such as alkylaminocarboxylate and alkylaminodicarboxylate, and nonionic surfactants such as polyoxyethylene alkylphenyl ether An amount corresponding to several mass% can be added to the polymer.

  Further, the protective layer preferably contains an inorganic layered compound for the purpose of improving oxygen barrier properties and image recording layer surface protective properties. Among inorganic layered compounds, fluorine-based swellable synthetic mica, which is a synthetic inorganic layered compound, is particularly useful. Specifically, inorganic layered compounds described in JP-A No. 2005-119273 are preferable.

The coating amount of the protective layer is preferably 0.05 to 10 g / m ^{2. When} the inorganic layered compound is contained, 0.1 to 5 g / m ² is more preferable, and when the inorganic layered compound is not contained. Is more preferably 0.5 to 5 g / m ² .

[Support]
The support used for the lithographic printing plate precursor according to the invention is not particularly limited as long as it is a dimensionally stable plate-like hydrophilic support. As the support, an aluminum plate is particularly preferable. Prior to using the aluminum plate, it is preferable to perform surface treatment such as roughening treatment or anodizing treatment. 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 selectively dissolves the surface chemically). For these treatments, the methods described in paragraph numbers [0241] to [0245] of JP-A-2007-206217 can be preferably used.
The support preferably has a center line average roughness of 0.10 to 1.2 μm. Within this range, good adhesion to the image recording layer, good printing durability and good stain resistance can be obtained.
The color density of the support is preferably from 0.15 to 0.65 in terms of the reflection density value. Within this range, good image formability by preventing halation during image exposure and good plate inspection after development 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, and even more preferably from 0.2 to 0.3 mm.

<Hydrophilic treatment>
In the lithographic printing plate precursor according to the invention, in order to improve the hydrophilicity of the non-image area and prevent printing stains, the support surface is subjected to a hydrophilic treatment, or an undercoat is provided between the support and the image recording layer. It is also suitable to provide a layer.
Examples of the hydrophilization treatment of the support surface include alkali metal silicate treatment in which the support is immersed in an aqueous solution such as sodium silicate or electrolytic treatment, a method of treatment with potassium zirconate fluoride, a method of treatment with polyvinylphosphonic acid, and the like. Although mentioned, the method of immersing in the polyvinylphosphonic acid aqueous solution is used preferably.

<Undercoat layer>
Moreover, when the lithographic printing plate precursor according to the invention has an undercoat layer as in the second embodiment, the undercoat layer contains the specific polymer compound (A). In this case, the content of the specific polymer compound (A) is as described above. The undercoat layer may further contain a compound other than the specific polymer compound (A). Examples of such a further compound include an addition-polymerizable ethylenic double resin described in JP-A-10-282679. Preferable examples include a silane coupling agent having a bonding reactive group and a phosphorus compound having an ethylenic double bond reactive group described in JP-A-2-304441. Particularly preferred compounds include compounds having a polymerizable group such as a methacryl group and an allyl group and a support-adsorptive group such as a sulfonic acid group, a phosphoric acid group and a phosphoric acid ester. A compound having a hydrophilicity-imparting group such as an ethylene oxide group in addition to the polymerizable group and the support-adsorbing group can also be exemplified as a suitable compound.
The undercoat layer is formed by applying water on a support and drying a solution prepared by dissolving the above compound in water, an organic solvent such as methanol, ethanol, methyl ethyl ketone, or a mixed solvent thereof, or water, methanol, ethanol, methyl ethyl ketone. The above compound can be adsorbed by immersing the support in a solution obtained by dissolving the above compound in an organic solvent such as the above or a mixed solvent thereof, and then washed and dried with water or the like. In the former method, a solution of the above compound having a concentration of 0.005 to 10% by mass can be applied by various methods.
For example, any method such as bar coater coating, spin coating, spray coating, or curtain coating may be used. In the latter method, the concentration of the solution is 0.01 to 20% by mass, preferably 0.05 to 5% by mass, the immersion temperature is 20 to 90 ° C., preferably 25 to 50 ° C., and the immersion time. Is 0.1 second to 20 minutes, preferably 2 seconds to 1 minute.
The coating amount (solid content) of the undercoat layer is preferably from 0.1 to 100 mg / m ² , and more preferably from ¹ to 30 mg / m ² .

[Back coat layer]
The lithographic printing plate precursor according to the invention can be provided with a back coat on the back surface of the support, if necessary. Examples of the back coat include hydrolysis and polycondensation of organic polymer compounds described in JP-A-5-45885, organometallic compounds or inorganic metal compounds described in JP-A-6-35174. A coating layer made of a metal oxide obtained in this manner is preferred. Among them, it is inexpensive to use a silicon alkoxy compound such as Si (OCH ₃ ) ₄ , Si (OC ₂ H ₅ ) ₄ , Si (OC ₃ H ₇ ) ₄ , Si (OC ₄ H ₉ ) _4. It is preferable in terms of easy availability.

[Preparation method of lithographic printing plate]
A lithographic printing plate can be produced by subjecting the lithographic printing plate precursor according to the invention to image exposure and development.

<Image exposure>
The lithographic printing plate precursor is imagewise exposed by laser exposure through a transparent original image having a line image, a halftone dot image or the like, or by laser beam scanning by digital data.
The wavelength of the light source is preferably 300 to 450 nm or 750 to 1400 nm. In the case of a light source of 300 to 450 nm, a lithographic printing plate precursor having a sensitizing dye having an absorption maximum in this wavelength region in the image recording layer is preferably used, and in the case of a light source of 750 to 1400 nm, absorption is performed in this wavelength region. A lithographic printing plate precursor containing an infrared absorbing agent, which is a sensitizing dye, in the image recording layer is preferably used. As the light source of 300 to 450 nm, a semiconductor laser is suitable. As a light source of 750 to 1400 nm, a solid laser and a semiconductor laser emitting infrared rays are suitable. Regarding the infrared laser, the output is preferably 100 mW or more, the exposure time per pixel is preferably within 20 microseconds, 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. The exposure mechanism may be any of an internal drum system, an external drum system, a flat bed system, and the like.
Image exposure can be performed by a conventional method using a plate setter or the like. In the case of on-press development, the lithographic printing plate precursor may be mounted on a printing press and then image exposure may be performed on the printing press.

<Development processing>
The development processing is (1) a method of developing with a developer having a pH of 2 to 14 (developer processing method), or (2) a method of developing on a printing press while adding dampening water and / or ink ( (On-press development system).

<Developer processing method>
In the developer processing method, the lithographic printing plate precursor subjected to image exposure is processed with a developer having a pH of 2 to 14, and the image recording layer in the non-exposed portion is removed to prepare a lithographic printing plate.
In the development processing using a highly alkaline developer (pH 12 or more), usually, the protective layer is removed by a pre-water washing step, then alkali development is performed, the alkali is washed away by water in the post-water washing step, gum solution treatment is performed, and drying is performed. A lithographic printing plate is produced by drying in the process.
According to a preferred embodiment of the present invention, a developer having a pH of 2 to 11 is used. In this embodiment, it is preferable that a surfactant or a water-soluble polymer compound is contained in the developer, whereby the development and the gum solution treatment can be performed simultaneously. Therefore, the post-water washing step is not particularly required, and the development-gum solution treatment can be performed with one solution. Further, no pre-water washing step is required, and the protective layer can be removed simultaneously with the development-gum solution treatment. After the development-gum treatment, for example, it is preferable to perform drying after removing excess developer using a squeeze roller.

  The developer treatment of the lithographic printing plate precursor according to the invention is carried out in accordance with a conventional method at a temperature of 0 to 60 ° C., preferably about 15 to 40 ° C., for example, by immersing the exposed lithographic printing plate precursor in a developer and brushing It can be carried out by a method of rubbing with a brush, a method of spraying a developer by spraying and rubbing with a brush.

  In the present invention, the development treatment with a developer having a pH of 2 to 14 can be preferably carried out by an automatic development processor equipped with a developer supply means and a rubbing member. An automatic developing processor using a rotating brush roll as the rubbing member is particularly preferable. Further, the automatic processor preferably includes a means for removing excess developer such as a squeeze roller and a drying means such as a warm air device after the development processing means. Further, the automatic development processor may be provided with a preheating means for heat-treating the lithographic printing plate precursor after image exposure before the development processing means.

FIG. 1 schematically shows an example of an automatic developing processor used in the lithographic printing plate preparation method of the present invention. The automatic developing machine of FIG. 1 basically includes a developing unit 6 and a drying unit 10, and the lithographic printing plate precursor 4 is developed in the developing tank 20 and dried in the drying unit 10.
Another embodiment of the automatic developing processor used in the method for producing a lithographic printing plate according to the present invention will be briefly described with reference to FIG.
An automatic development processor 100 shown in FIG. 2 includes a chamber having an outer shape formed by a machine frame 202, and is preheated continuously along the transport direction (arrow A) of the transport path 11 of the planographic printing plate precursor. It has a (preheat) unit 200, a developing unit 300, and a drying unit 400.
The preheating unit 200 includes a heating chamber 208 having a carry-in port 212 and a carry-out port 218, and a skewer roller 210, a heater 214, and a circulation fan 216 are disposed therein.

The developing unit 300 is separated from the preheating unit 200 by an outer panel 310, and the outer panel 310 is provided with a slit-shaped insertion port 312.
Inside the developing unit 300, a processing tank 306 having a developing tank 308 filled with a developer and an insertion roller pair 304 for guiding the planographic printing plate precursor into the processing tank 306 are provided. The upper part of the developing tank 308 is covered with a shielding lid 324.

Inside the developing tank 308, a guide roller 344 and a guide member 342, a submerged roller pair 316, a brush roller pair 322, a brush roller pair 326, and a carry-out roller pair 318 are arranged in parallel from the upstream side in the transport direction. The lithographic printing plate precursor conveyed into the developing tank 308 is immersed in the developer and passes between rotating brush roller pairs 322 and 326 to remove non-image portions.
A spray pipe 330 is provided below the pair of brush rollers 322 and 326. The spray pipe 330 is connected to a pump (not shown), and the developer in the developing tank 308 sucked by the pump is ejected from the spray pipe 330 into the developing tank 308.

An overflow port 51 formed at the upper end of the first circulation pipe C1 is provided on the side wall of the developing tank 308, and excess developer flows into the overflow port 51, and the first circulation pipe C1. And is discharged to an external tank 50 provided outside the developing unit 300.
A second circulation pipe C2 is connected to the external tank 50, and a filter portion 54 and a developer supply pump 55 are provided in the second circulation pipe C2. The developer is supplied from the external tank 50 to the developer tank 308 by the developer supply pump 55. In the external tank 50, an upper limit liquid level meter 52 and a lower limit liquid level meter 53 are provided.
The developing tank 308 is connected to the replenishment water tank 71 via the third circulation pipe C3. A water replenishment pump 72 is provided in the third circulation pipe C 3, and water stored in the replenishment water tank 71 is supplied to the developing tank 308 by the water replenishment pump 72.
A liquid temperature sensor 336 is installed on the upstream side of the submerged roller pair 316, and a liquid level meter 338 is installed on the upstream side of the carry-out roller pair 318.

The partition plate 332 disposed between the developing unit 300 and the drying unit 400 is provided with a slit-shaped insertion port 334. A shutter (not shown) is provided in the passage between the developing unit 300 and the drying unit 400, and when the planographic printing plate precursor 11 does not pass through the passage, the passage is closed by the shutter.
The drying unit 400 includes a support roller 402, ducts 410 and 412, a transport roller pair 406, ducts 410 and 412, and a transport roller pair 408 in this order. A slit hole 414 is provided at the tip of the ducts 410 and 412. The drying unit 400 is provided with drying means such as hot air supply means and heat generation means (not shown). The drying unit 400 is provided with a discharge port 404, and the planographic printing plate dried by the drying means is discharged from the discharge port 404.

  In the present invention, the developer used for the developer processing is preferably an aqueous solution containing water as a main component (containing 60% by mass or more of water). In particular, an aqueous solution containing a surfactant having a pH of 2 to 11 (anionic, nonionic, cationic, amphoteric ion, etc.) or an aqueous solution containing a water-soluble polymer compound is preferable. An aqueous solution containing both a surfactant and a water-soluble polymer compound is also preferred. The pH of the developer is more preferably 3.5 to 11, further preferably 6 to 11, and particularly preferably 6.5 to 10.5.

  The anionic surfactant used in the developer of the present invention is not particularly limited, but fatty acid salts, abietic acid salts, hydroxyalkanesulfonic acid salts, alkanesulfonic acid salts, dialkylsulfosuccinic acid salts, linear alkylbenzenesulfonic acid salts. Branched alkylbenzene sulfonates, alkyl naphthalene sulfonates, alkyl diphenyl ether (di) sulfonates, alkylphenoxy polyoxyethylene alkyl sulfonates, polyoxyethylene alkyl sulfophenyl ether salts, N-alkyl-N-oleyl taurine Sodium, N-alkylsulfosuccinic acid monoamide disodium salt, petroleum sulfonate, sulfated castor oil, sulfated beef tallow oil, fatty acid alkyl ester sulfate ester salt, alkyl Acid ester salts, polyoxyethylene alkyl ether sulfates, fatty acid monoglyceride sulfates, polyoxyethylene alkylphenyl ether sulfates, polyoxyethylene styryl phenyl ether sulfates, alkyl phosphate esters, polyoxyethylene alkyl ether phosphates Ester salts, polyoxyethylene alkylphenyl ether phosphate ester salts, saponified saponified styrene-maleic anhydride copolymers, partially saponified olefin-maleic anhydride copolymers, naphthalene sulfonate formalin condensates, etc. Is mentioned. Of these, alkylbenzene sulfonates, alkylnaphthalene sulfonates, and alkyl diphenyl ether (di) sulfonates are particularly preferably used.

  Although it does not specifically limit as a cationic surfactant used for the developing solution of this invention, A conventionally well-known thing can be used. Examples thereof include alkylamine salts, quaternary ammonium salts, alkyl imidazolinium salts, polyoxyethylene alkylamine salts, and polyethylene polyamine derivatives.

  The nonionic surfactant used in the developer of the present invention is not particularly limited, but is a polyethylene glycol type higher alcohol ethylene oxide adduct, alkylphenol ethylene oxide adduct, alkyl naphthol ethylene oxide adduct, phenol ethylene oxide adduct. , Naphthol ethylene oxide adduct, fatty acid ethylene oxide adduct, polyhydric alcohol fatty acid ester ethylene oxide adduct, higher alkylamine ethylene oxide adduct, fatty acid amide ethylene oxide adduct, fat and oil ethylene oxide adduct, polypropylene glycol ethylene oxide addition Dimethylsiloxane-ethylene oxide block copolymer, dimethylsiloxane- (propylene oxide-ethylene oxide) Id) block copolymer, fatty acid ester of polyhydric alcohol type glycerol, fatty acid ester of pentaerythritol, fatty acid ester of sorbitol and sorbitan, fatty acid ester of sucrose, alkyl ether of polyhydric alcohol, fatty acid amide of alkanolamines, etc. It is done. Among these, those having an aromatic ring and an ethylene oxide chain are preferable, and an alkyl-substituted or unsubstituted phenol ethylene oxide adduct or an alkyl-substituted or unsubstituted naphthol ethylene oxide adduct is more preferable.

  The zwitterionic surfactant used in the developer of the present invention is not particularly limited, and examples thereof include amine oxides such as alkyldimethylamine oxide, betaines such as alkylbetaine, and amino acids such as sodium alkylamino fatty acid. . In particular, alkyldimethylamine oxide which may have a substituent, alkylcarboxybetaine which may have a substituent, and alkylsulfobetaine which may have a substituent are preferably used. Specifically, a compound represented by the formula (2) in paragraph No. [0256] of JP-A-2008-203359, a formula (I), a formula (II) in paragraph No. [0028] of JP-A-2008-276166, A compound represented by the formula (VI) or a compound represented by paragraph numbers [0022] to [0029] of JP-A-2009-47927 can be used.

  Two or more surfactants may be used in the developer. 0.01-20 mass% is preferable and, as for the quantity of surfactant contained in a developing solution, 0.1-10 mass% is more preferable.

  Examples of the water-soluble polymer compound used in the developer of the present invention include soybean polysaccharide, modified starch, gum arabic, dextrin, fiber derivatives (eg, carboxymethyl cellulose, carboxyethyl cellulose, methyl cellulose, etc.) and modified products thereof, pullulan, polyvinyl Alcohol and derivatives thereof, polyvinylpyrrolidone, polyacrylamide and acrylamide copolymer, vinyl methyl ether / maleic anhydride copolymer, vinyl acetate / maleic anhydride copolymer, styrene / maleic anhydride copolymer, polyvinyl sulfonic acid and The salt, polystyrene sulfonic acid, its salt, etc. are mentioned.

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

  As the modified starch, known ones can be used. For example, starch such as corn, potato, tapioca, rice, wheat etc. is decomposed with acid or enzyme in the range of 5-30 glucose residues per molecule, and further alkali It can be made by a method of adding oxypropylene in the inside.

  Two or more water-soluble polymer compounds may be used in combination in the developer. The content of the water-soluble polymer compound in the developer is preferably from 0.1 to 20% by mass, and more preferably from 0.5 to 10% by mass.

  The developer used in the present invention may contain a pH buffer. The developer of the present invention can be used without particular limitation as long as it is a buffering agent that exhibits a buffering action at a pH of 2 to 14. In the present invention, weakly alkaline buffering agents are preferably used. For example, (a) carbonate ions and hydrogen carbonate ions, (b) borate ions, (c) water-soluble amine compounds and ions of the amine compounds, and their Combination use etc. are mentioned. That is, for example, (a) a combination of carbonate ion and hydrogen carbonate ion, (b) borate ion, or (c) a combination of a water-soluble amine compound and an ion of the amine compound exhibits a pH buffering action in the developer. Even when the developer is used for a long period of time, fluctuations in pH can be suppressed, and therefore, development loss due to fluctuations in pH, development debris generation and the like can be suppressed. Particularly preferred is a combination of carbonate ions and bicarbonate ions.

  (A) In order to allow carbonate ions and hydrogen carbonate ions to be present in the developer, carbonate and bicarbonate may be added to the developer, or the pH is adjusted after adding carbonate or bicarbonate. Thus, carbonate ions and hydrogen carbonate ions may be generated. 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. These may be used alone or in combination of two or more.

  When (a) a combination of carbonate ions and bicarbonate ions is employed as the pH buffer, the total amount of carbonate ions and bicarbonate ions is preferably 0.05 to 5 mol / L, preferably 0.07 to 2 mol relative to the developer. / L is more preferable, and 0.1 to 1 mol / L is particularly preferable. When the total amount is 0.05 mol / L or more, developability and processing ability are hardly lowered, and when it is 5 mol / L or less, it is difficult to form precipitates and crystals. It is difficult to gel, and it is difficult to cause waste liquid treatment.

(B) In order to make borate ions exist in the developer, after adding boric acid or borate to the developer, the pH is adjusted using an alkali or an alkali and an acid. To generate an appropriate amount of borate ions.
The boric acid or borate used here is not particularly limited, and examples of boric acid include orthoboric acid, metaboric acid, and tetraboric acid. Among them, orthoboric acid and tetraboric acid are preferable. Examples of borates include alkali metal salts or alkaline earth metal salts, such as orthoborate, diborate, metaborate, tetraborate, pentaborate, and octaborate. Of these, orthoborate and tetraborate, particularly alkali metal tetraborate are preferred. Preferred tetraborate salts include sodium tetraborate, potassium tetraborate, and lithium tetraborate. Among them, sodium tetraborate is preferable. Two or more borates may be used in combination.
As the boric acid or borate used in the present invention, orthoboric acid, tetraboric acid or sodium tetraborate is particularly preferable. Boric acid and borates may be used in combination with the developer.

  When (b) borate ions are employed as the pH buffering agent, the total amount of borate ions is preferably 0.05 to 5 mol / L, more preferably 0.1 to 2 mol / L with respect to the developer. 2-1 mol / L is particularly preferable. When the total amount of borate is 0.05 mol / L or more, developability and processing ability are hardly lowered, and when it is 5 mol / L or less, it is difficult to form precipitates and crystals. It becomes difficult to gel during neutralization, and the waste liquid treatment is unlikely to be hindered.

(C) Water-soluble amine compounds and ions of the amine compounds are not particularly limited, but water-soluble amine compounds selected from monoethanolamine, diethanolamine, triethanolamine, N-hydroxyethylmorpholine, and 4-dimethylaminopyridine. Amine compounds and ions of the amine compounds are preferred. These may be used alone or in combination of two or more.

  When (c) an ion of a water-soluble amine compound and its salt is employed as the pH buffering agent, the total amount of the water-soluble amine compound and its salt is preferably 0.005 to 5 mol / L with respect to the developer. 0.01 to 2 mol / L is more preferable, and 0.01 to 1 mol / L is particularly preferable. When the total amount of ions of the water-soluble amine compound is within this range, the developability and processing ability are not lowered, while the waste liquid treatment is easy.

  The developer of the present invention may contain an organic solvent. Examples of the organic solvent that can be contained include aliphatic hydrocarbons (hexane, heptane, Isopar E, H, G (manufactured by Esso Chemical Co., Ltd.)), aromatic hydrocarbons (toluene, xylene, etc.), halogens, and the like. Hydrocarbons (methylene dichloride, ethylene dichloride, trichlene, monochlorobenzene, etc.) and polar solvents. Examples of polar solvents include alcohols (methanol, ethanol, propanol, isopropanol, 1-butanol, 1-pentanol, 1-hexanol, 1-heptanol, 1-octanol, 2-octanol, 2-ethyl-1-hexanol, 1 -Nonanol, 1-decanol, benzyl alcohol, ethylene glycol monomethyl ether, 2-ethoxyethanol, diethylene glycol monoethyl ether, diethylene glycol monohexyl ether, triethylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monomethyl ether, polyethylene glycol monomethyl Ether, polypropylene glycol, tetraethylene glycol, ethylene glycol monobutyl ether Ter, ethylene glycol monobenzyl ether, ethylene glycol monophenyl ether, propylene glycol monophenyl ether, methylphenyl carbinol, n-amyl alcohol, methyl amyl alcohol, etc.), ketones (acetone, methyl ethyl ketone, ethyl butyl ketone, methyl isobutyl ketone) , Cyclohexanone, etc.), esters (ethyl acetate, propyl acetate, butyl acetate, amyl acetate, benzyl acetate, methyl lactate, butyl lactate, ethylene glycol monobutyl acetate, propylene glycol monomethyl ether acetate, diethylene glycol acetate, diethyl phthalate, butyl levulinate Etc.), others (triethyl phosphate, tricresyl phosphate, N-phenylethanolamine) , N- phenyldiethanolamine, N- methyldiethanolamine, N- ethyldiethanolamine, 4- (2-hydroxyethyl) morpholine, N, N- dimethylacetamide, N- methylpyrrolidone and the like) and the like.

  Two or more organic solvents can be used in combination in the developer. When the organic solvent is insoluble in water, it can be used after being solubilized in water using a surfactant or the like. When the developer contains an organic solvent, the concentration of the organic solvent is preferably less than 40% by mass from the viewpoint of safety and flammability.

  In addition to the above components, the developer of the present invention may contain preservatives, chelate compounds, antifoaming agents, organic acids, inorganic acids, inorganic salts, and the like. Specifically, compounds described in paragraph numbers [0266] to [0270] of JP-A-2007-206217 can be preferably used.

  The developer of the present invention can be used as a developer and a development replenisher for an exposed lithographic printing plate precursor. Further, the present invention can be preferably applied to the automatic developing processor as described above. When developing using an automatic developing processor, the developing solution becomes fatigued according to the amount of processing, so that the processing capability may be restored by using a replenishing solution or a fresh developing solution.

<On-press development method>
In the on-press development system, an image-exposed lithographic printing plate precursor is supplied with oil-based ink and an aqueous component on a printing machine, and the image recording layer in the non-image area is removed to produce a lithographic printing plate.
In other words, after image exposure of the lithographic printing plate precursor, it is mounted on the printing machine without any development processing, or after the lithographic printing plate precursor is mounted on the printing machine, image exposure is performed on the printing machine. When printing is performed by supplying the oil-based ink and the aqueous component, the uncured image recording layer is dissolved or dispersed in the non-image area by the supplied oil-based ink and / or the aqueous component in the initial stage of printing. And a hydrophilic surface is exposed at the portion. On the other hand, in the exposed portion, the image recording layer cured by exposure forms an oil-based ink receiving portion having a lipophilic surface. Oil-based ink or water-based component may be first supplied to the plate surface, but oil-based ink is supplied first in order to prevent the water-based component from being contaminated by the removed image recording layer component. Is preferred. In this way, the lithographic printing plate precursor is subjected to on-press development on a printing machine and used as it is for printing a large number of sheets. As the oil-based ink and the aqueous component, ordinary lithographic printing ink and fountain solution are preferably used.

  In the method of preparing a lithographic printing plate from the lithographic printing plate precursor according to the present invention, the entire lithographic printing plate precursor is exposed before exposure, during exposure, and from exposure to development, regardless of the development method. You may heat. By such heating, an image forming reaction in the image recording layer is promoted, and advantages such as improvement in sensitivity and printing durability and stabilization of sensitivity may occur. In the case of the developer processing method, it is also effective to perform whole surface post-heating or whole surface exposure on the image after the development processing for the purpose of improving the image strength and printing durability. Usually, heating before development is preferably performed under a mild condition of 150 ° C. or less. If the temperature is too high, problems such as curing of the non-image area may occur. Very strong conditions are used for heating after development. Usually, it is the range of 100-500 degreeC. If the temperature is low, sufficient image reinforcing action cannot be obtained. If the temperature is too high, problems such as deterioration of the support and thermal decomposition of the image area may occur.

  EXAMPLES Hereinafter, although an Example demonstrates this invention in detail, this invention is not limited to these. Hereinafter, the ratio of the repeating units for the polymer compound is a molar ratio.

Example (A) Production of Specific Polymer Compound (A) First, a synthesis example of a radical polymerizable unsaturated group-containing monomer for obtaining the specific polymer compound (A) having (a1) of the present invention will be described.
<Synthesis of Radical Polymerizable Monomer M-1>
A 200 ml flask equipped with a condenser and a stirrer was charged with trans-1,4-dibromo-2-butene: 58.78 g and 3,3-dimethylaminopropyl methacrylamide: 6.81 g, heated to 60 ° C., and stirred for 1 hour. did. Thereafter, 100 ml of ethyl acetate was added, and the resulting white solid was collected by filtration and washed again with ethyl acetate. The obtained solid was dissolved in 10 g of ion-exchanged water, 5.04 g of sodium sulfite was added, and the mixture was heated to 90 ° C. and stirred for 30 minutes. After collecting the obtained lower organic layer, 10 g of silver oxide was added and filtered, and the resulting liquid was added with ion exchange resin Amberlyst 15: 2 g and filtered again. 500 ml of acetonitrile was added to the obtained filtrate, the precipitated NaCl was removed by filtration, and dried under reduced pressure to obtain radical polymerizable monomer M-1.

<Synthesis of radical polymerizable monomer M-38>
A 200 ml flask equipped with a condenser and a stirrer was charged with 1,4-bis (bromomethyl) cyclohexane: 54.0 g and 3,3-dimethylaminopropyl methacrylamide: 6.81 g, heated to 60 ° C., and stirred for 1 hour. Thereafter, 100 ml of ethyl acetate was added, and the resulting white solid was collected by filtration and washed again with ethyl acetate. The obtained solid was dissolved in 10 g of ion-exchanged water, 5.04 g of sodium sulfite was added, and the mixture was heated to 90 ° C. and stirred for 30 minutes. After collecting the obtained lower organic layer, 10 g of silver oxide was added and filtered, and the resulting liquid was added with ion exchange resin Amberlyst 15: 2 g and filtered again. 500 ml of acetonitrile was added to the obtained filtrate, the precipitated NaCl was removed by filtration, and dried under reduced pressure to obtain radical polymerizable monomer M-38.

<Synthesis of Specific Polymer Compound P-1>
A 200 ml flask equipped with a condenser and a stirrer was charged with N-methylpyrrolidone: 14.66 g and vinylphosphonic acid: 3.78 g and heated to 70 ° C. under a nitrogen stream. To this was added dropwise a solution of radical polymerizable monomers M-1, V-601 (manufactured by Wako Pure Chemical Industries, Ltd.): 0.161 g, N-methylpyrrolidone: 14.66 g over 4 hours. V-601: 0.161g was added after completion | finish of dripping, and it heated up to 80 degreeC, and also stirred for 2 hours, and obtained the specific polymer compound (P-1). It was 18,000 as a result of measuring a mass mean molecular weight by the gel permeation chromatography method (GPC) which used polyethyleneglycol as the standard substance for the obtained specific polymer compound (P-1).

Example (B) Hydrophilic film (1) Preparation of hydrophilic film A polymer film coating solution having the following composition was applied to a PET film having a thickness of 250 μm (manufactured by Toray Industries, Inc., Lumirror 100T) with a bar coater and heated to 120 ° C. And dried for 1 minute to form a polymer film on the surface. The dry coating amount of the polymer film is as shown in Table 7 below.

<Polymer film coating solution>
-Specific polymer compound (A) described in Table 7 or comparative polymer compound 0.50 g
・ Methanol 90.0g
・ Water 10.0g

  Comparative polymer compounds (R-1) to (R-7) are shown below.

[Evaluation]
The surface hydrophilicity of each PET film having a polymer film formed on the surface was evaluated as follows. The results are shown in Table 7.
<Surface hydrophilicity>
A PET film having a polymer film formed on the surface was cut into a size of 20 mm × 40 mm and immersed in a glass cell filled with linseed oil (manufactured by TCI) for 5 minutes. After 1 minute from the immersion, 1 μl of distilled water was dropped on the sample surface. The contact angle after 60 seconds passed was measured with the time when the deposited water droplets began to spread wet as 0 seconds.

  As shown in Table 7, it can be seen that high hydrophilicity can be obtained by surface coating using the specific polymer compound (A). As described above, when the specific polymer compound (A) is used in the lithographic printing plate precursor, the hydrophilicity of the non-image area is increased and the penetration of the developer / fountain solution into the non-image area is promoted. It is presumed that a printed matter excellent in developability or on-press developability can be obtained. In addition, among the ink and dampening water supplied during printing, the dampening water is strongly adsorbed to the non-image area, thereby preventing the ink from adhering to the non-image area and obtaining a printed matter having excellent stain resistance. It is estimated that

Example (C) Planographic printing plate (Examples 1 to 96 and Comparative Examples 1 to 17)
(1) Preparation of planographic printing plate precursor [Preparation of aluminum support 1]
In order to remove rolling oil on the surface of an aluminum plate (material: JIS A1050) having a thickness of 0.3 mm, after degreasing at 50 ° C. for 30 seconds using a 10 mass% sodium aluminate aqueous solution, the hair diameter is 0.3 mm. The aluminum surface was grained using 3 bundle-planted nylon brushes and a pumice-water suspension (specific gravity 1.1 g / cm ³ ) having a median diameter of 25 μm and washed thoroughly with water. This plate was etched by being immersed in a 25 mass% aqueous sodium hydroxide solution at 45 ° C for 9 seconds, washed with water, further immersed in a 20 mass% 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 mass nitric acid aqueous solution (containing 0.5% by mass 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 nitric acid electrolysis was 175 C / dm ² when the aluminum plate was the anode. Then, water washing by spraying was performed.

Next, a 0.5% by mass hydrochloric acid aqueous solution (containing 0.5% by mass of aluminum ions) and an electrolytic solution having a liquid temperature of 50 ° C. and nitric acid electrolysis under the condition of an electric quantity of 50 C / dm ² when the aluminum plate is an anode. In the same manner as above, an electrochemical surface roughening treatment was performed, followed by washing with water by spraying. The plate was provided with a DC anodized film of 2.5 g / m ² at a current density of 15 A / dm ² using a 15% by mass sulfuric acid aqueous solution (containing 0.5% by mass of aluminum ions) as an electrolyte, then washed with water and dried. An aluminum support 1 was prepared.
The surface roughness of the support thus obtained was measured and found to be 0.51 μm (Ra indication according to JIS B0601).

[Preparation of aluminum support 2]
The aluminum support 1 was treated with a 1% by mass aqueous solution of sodium silicate at 20 ° C. for 10 seconds to produce an aluminum support 2. When the surface roughness was measured, it was 0.54 μm (Ra display according to JIS B0601).

[Preparation of Aluminum Support 3]
An aluminum plate (material 1050, tempered H16) having a thickness of 0.24 mm was immersed in a 5% aqueous sodium hydroxide solution kept at 65 ° C., degreased for 1 minute, and then washed with water. The aluminum plate was neutralized by immersion in a 10% aqueous hydrochloric acid solution maintained at 25 ° C. for 1 minute, and then washed with water. Subsequently, this aluminum plate was subjected to electrolytic surface roughening with an alternating current for 60 seconds under conditions of 25 ° C. and a current density of 100 A / dm ^{2 in} a 0.3 mass% hydrochloric acid aqueous solution, and then kept at 60 ° C. In addition, desmutting treatment was performed in a 5% aqueous sodium hydroxide solution for 10 seconds. This aluminum plate was anodized in a 15% sulfuric acid aqueous solution at 25 ° C., a current density of 10 A / dm ² , and a voltage of 15 V for 1 minute to produce an aluminum support 3. When the surface roughness was measured, it was 0.44 μm (Ra display according to JIS B0601).

(Formation of undercoat layer)
An undercoat layer coating solution having the following composition was applied onto the aluminum support 1, 2, or 3 with a bar coater and dried at 100 ° C. for 1 minute to form an undercoat layer. The dry coating amount of the undercoat layer was 12 mg / m ² .

<Undercoat layer coating solution>
-Specific high molecular compound (A) of Tables 8 and 9 or high molecular compound for comparison 0.50 g
・ Methanol 90.0g
・ Water 10.0g
[Formation of Image Recording Layer 1]
An image recording layer coating solution 1 having the following composition was bar coated on the undercoat layer and then oven-dried at 90 ° C. for 60 seconds to form an image recording layer 1 having a dry coating amount of 1.3 g / m ² .

<Image recording layer coating solution 1>
・ The following binder polymer (1) (mass average molecular weight: 50,000) 0.34 g
・ The following polymerizable compound (1) 0.68 g
(PLEX6661-O, manufactured by Degussa Japan)
・ The following sensitizing dye (1) 0.06 g
・ The following polymerization initiator (1) 0.18 g
・ The following chain transfer agent (1) 0.02 g
・ 0.40 g of ε-phthalocyanine pigment dispersion
(Pigment: 15 parts by mass, dispersant (allyl methacrylate / methacrylic acid
Copolymer (mass average molecular weight: 60,000, copolymer molar ratio: 83/17)):
(10 parts by mass, cyclohexanone: 15 parts by mass)
-Thermal polymerization inhibitor N-nitrosophenylhydroxylamine aluminum salt 0.01 g
-0.001 g of the following fluorosurfactant (1) (mass average molecular weight: 10,000)
・ Polyoxyethylene-polyoxypropylene condensate 0.02g
(Pluronic L44, manufactured by ADEKA Corporation)
・ Dispersion of yellow pigment 0.04g
(Yellow pigment Novoperm Yellow H2G (manufactured by Clariant): 15 parts by mass, dispersant (allyl methacrylate / methacrylic acid copolymer (mass average molecular weight: 60,000, copolymer molar ratio 83/17)): 10 parts by mass, cyclohexanone: 15 parts by mass)
・ 3.5 g of 1-methoxy-2-propanol
・ Methyl ethyl ketone 8.0g

[Formation of Image Recording Layer 2]
An image recording layer coating solution 2 having the following composition was bar coated on the undercoat layer and then oven-dried at 90 ° C. for 60 seconds to form an image recording layer 2 having a dry coating amount of 1.3 g / m ² .
<Image recording layer coating solution 2>
-Binder polymer (1) (mass average molecular weight: 50,000) 0.04 g
-The following binder polymer (2) (mass average molecular weight: 80,000) 0.30 g
・ Polymerizable compound (1) 0.17 g
(PLEX6661-O, manufactured by Degussa Japan)
-0.51 g of the following polymerizable compound (2)
・ The following sensitizing dye (2) 0.03 g
・ The following sensitizing dye (3) 0.015 g
・ The following sensitizing dye (4) 0.015 g
・ The above polymerization initiator (1) 0.13 g
・ Chain transfer agent: Mercaptobenzothiazole 0.01g
・ 0.40 g of ε-phthalocyanine pigment dispersion
(Pigment: 15 parts by mass, dispersant (allyl methacrylate / methacrylic acid copolymer (mass average molecular weight: 60,000, copolymer molar ratio: 83/17)): 10 parts by mass, cyclohexanone: 15 parts by mass)
・ Thermal polymerization inhibitor 0.01g
N-nitrosophenylhydroxylamine aluminum salt-Fluorosurfactant (1) (mass average molecular weight: 10,000) 0.001 g
・ 3.5 g of 1-methoxy-2-propanol
・ Methyl ethyl ketone 8.0g

[Formation of Image Recording Layer 3]
An image recording layer coating solution 3 having the following composition was bar coated on the undercoat layer and then oven dried at 100 ° C. for 60 seconds to form an image recording layer 3 having a dry coating amount of 1.0 g / m ² . The image recording layer coating solution 3 was prepared by mixing and stirring the following photosensitive solution (1) and hydrophobized precursor solution (1) immediately before coating.

<Photosensitive solution (1)>
・ The following binder polymer (3) 0.162 g
・ The following infrared absorber (1) 0.030 g
-The following polymerization initiator (3) 0.162g
・ Polymerizable compound (Aronix M215, manufactured by Toagosei Co., Ltd.) 0.385 g
・ Pionine A-20 (Takemoto Yushi Co., Ltd.) 0.055g
・ The following oil sensitizer (1) 0.044 g
・ 0.008 g of the above-mentioned fluorosurfactant (1)
・ Methyl ethyl ketone 1.091g
・ 1-methoxy-2-propanol 8.609g

<Hydrophobic precursor liquid (1)>
-Hydrophobic precursor aqueous dispersion (1) below 2.640 g
・ Distilled water 2.425g

(Production of hydrophobized precursor aqueous dispersion (1))
A stirrer, thermometer, dropping funnel, nitrogen inlet tube, reflux condenser is applied to a 1000 ml four-necked flask, and 350 mL of distilled water is added while deoxygenating by introducing nitrogen gas, and the internal temperature becomes 80 ° C. Until heated. Add 1.5 g of sodium dodecyl sulfate as a dispersant, 0.45 g of ammonium persulfide as an initiator, and then add a mixture of 45.0 g of glycidyl methacrylate and 45.0 g of styrene from the dropping funnel to about 1 It was added dropwise over time. After the completion of the dropwise addition, the reaction was continued as it was for 5 hours, and then the unreacted monomer was removed by steam distillation. Thereafter, the mixture was cooled and adjusted to pH 6 with ammonia water, and finally purified water was added so that the nonvolatile content was 15% by mass to obtain a hydrophobized precursor aqueous dispersion (1) composed of polymer fine particles. The particle size distribution of the polymer fine particles had a maximum value at a particle size of 60 nm.

  The particle size distribution is obtained by taking an electron micrograph of polymer fine particles, measuring the total particle size of 5000 particles on the photograph, and dividing the obtained particle size measurement value from the maximum value to 0 on a logarithmic scale by 50. Then, the appearance frequency of each particle size was plotted and determined. For non-spherical particles, the particle size of spherical particles having the same particle area as that on the photograph was used as the particle size.

[Formation of Protective Layer 1]
A protective layer coating solution 1 having the following composition was coated on the image recording layer using a bar so that the dry coating amount was 0.75 g / m ^2, and then dried at 125 ° C. for 70 seconds to form a protective layer. 1 was formed.

[Protective layer coating solution 1]
Polyvinyl alcohol (degree of saponification: 98 mol%, degree of polymerization: 500) 40 g
・ Polyvinylpyrrolidone (mass average molecular weight: 50,000) 5 g
・ Poly [vinyl pyrrolidone / vinyl acetate (molar ratio: 1/1)] 0.5 g
(Mass average molecular weight: 70,000)
・ Surfactant (Emalex 710, manufactured by Nippon Emulsion Co., Ltd.) 0.5g
・ 950g of water

[Formation of Protective Layer 2]
A protective layer coating solution 2 having the following composition was coated on the image recording layer using a bar so that the dry coating amount was 0.75 g / m ^2, and then dried at 125 ° C. for 70 seconds to protect the protective layer. 2 was formed.

[Protective layer coating solution 2]
-1.5 g of the following inorganic layered compound dispersion (1)
・ 0.55 g of 6% by weight aqueous solution of sulfonic acid-modified polyvinyl alcohol
(Nippon Synthetic Chemical Industry Co., Ltd. CKS50, saponification degree 99 mol% or more, polymerization degree 300)
・ Polyvinyl alcohol 6 mass% aqueous solution 0.03g
(Kuraray Co., Ltd. PVA-405, saponification degree 81.5 mol%, polymerization degree 500) 6 mass% aqueous solution-1 mass% aqueous solution of surfactant (Nippon Emulsion Co., Ltd. Emarex 710) 8.60 g
・ Ion-exchanged water 6.0g

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

  The above-mentioned aluminum support, undercoat layer coating solution, image recording layer coating solution and protective layer coating solution are combined as shown in Tables 8 and 9, and the planographic printing plate precursors A-1 to A-58 of the present invention, comparative planographic printing Plate original plates B-1 to B-10 were prepared.

(2) Evaluation of planographic printing plate precursor
[Examples 1 to 63 and Comparative Examples 1 to 11]
[Exposure, development and printing]
Each lithographic printing plate precursor shown in Tables 10, 11 and 12 was prepared using FUJIFILM Electronic Imaging Ltd. Image exposure was performed with a Violet semiconductor laser plate setter Vx9600 (InGaN-based semiconductor laser (with an emission wavelength of 405 nm ± 10 nm / output 30 mW) mounted) manufactured by (FFEI). Image exposure was performed at a resolution of 2,438 dpi, using an FM screen (TAFFETA 20) manufactured by Fuji Film Co., Ltd., with a plate surface exposure of 0.05 mJ / cm ² so that the dot area ratio was 50%.
Next, after preheating at 100 ° C. for 30 seconds, development processing was carried out using an automatic developing processor having a structure as shown in FIG. The automatic processor has one brush roll with an outer diameter of 50 mm in which fibers made of polybutylene terephthalate (hair diameter 200 μm, hair length 17 mm) are implanted, and rotates 200 times per minute in the same direction as the conveying direction ( The peripheral speed of the brush tip was 0.52 m / sec). The temperature of the developer was 30 ° C. The planographic printing plate precursor was transported at a transport speed of 100 cm / min. After the development processing, drying was performed in a drying section. The drying temperature was 80 ° C. However, when the developer 2 was used, it was washed with water before the post-development drying step.

  The compositions of the developers 1 to 5 are shown below. In the following composition, New Coal B13 (manufactured by Nippon Emulsifier Co., Ltd.) is polyoxyethylene β-naphthyl ether (oxyethylene average number n = 13), and gum arabic has a mass average molecular weight of 200,000.

<Developer 1>
・ Sodium carbonate 13.0g
・ 7.0g sodium bicarbonate
・ New call B13 50.0g
・ Primary ammonium phosphate 2.0g
・ 0.01 g of 2-bromo-2-nitropropane-1,3-diol
-2-methyl-4-isothiazolin-3-one 0.01 g
・ Trisodium citrate 15.0g
・ Distilled water 913.98 g
(PH: 9.8)

<Developer 2>
・ Potassium hydroxide 0.15g
・ New call B13 5.0g
・ Chillest 400 (chelating agent) 0.1g
・ Distilled water 94.75g
(PH: 12.05)

<Developer 3>
・ Gum Arabic 25.0g
・ Enzyme-modified potato starch 70.0g
・ Dioctylsulfosuccinate sodium salt 5.0 g
・ Primary ammonium phosphate 1.0g
・ Citric acid 1.0g
・ 0.01 g of 2-bromo-2-nitropropane-1,3-diol
-2-methyl-4-isothiazolin-3-one 0.01 g
・ The following amphoteric surfactant (W-1) 70.0 g
・ 3.0 g of the following anionic surfactant (AN-1)
・ Distilled water 824.98 g
(Phosphoric acid and sodium hydroxide are added to adjust the pH to 4.5)

<Developer 4>
・ Water 937.2g
-23.8 g of the following anionic surfactant (W-2)
・ Phosphoric acid 3g
・ Phenoxypropanol 5g
・ Triethanolamine 6g
・ Potatodextrin 25g

<Developer 5>
・ Water 88.6g
-2.4 g of the following nonionic surfactant (W-3)
-2.4 g of the following nonionic surfactant (W-4)
・ Nonionic surfactant 1.0g
(Emalex 710, manufactured by Nippon Emulsion Co., Ltd.)
・ Phenoxypropanol 1.0g
・ Octanol 0.6g
・ N- (2-hydroxyethyl) morpholine 1.0 g
・ Triethanolamine 0.5g
・ Sodium gluconate 1.0g
・ Trisodium citrate 0.5g
・ Ethylenediaminetetraacetate tetrasodium 0.05g
・ Polystyrenesulfonic acid 1.0g
(Versa TL77 (30% solution), manufactured by Alco Chemical)
(Add phosphoric acid and adjust pH to 7.0)

  The obtained lithographic printing plate is attached to a printing machine SOR-M manufactured by Heidelberg, and fountain solution (EU-3 (etch solution manufactured by FUJIFILM Corporation) / water / isopropyl alcohol = 1/89/10 (volume ratio). )) And TRANS-G (N) black ink (manufactured by Dainippon Ink & Chemicals, Inc.), printing was performed at a printing speed of 6000 sheets per hour.

[Evaluation]
Each lithographic printing plate precursor was evaluated for printing durability, stain resistance, stain resistance after aging and developability as follows. The results are shown in Tables 10-12.
<Print durability>
As the number of printed sheets increased, the image recording layer was gradually worn out and the ink acceptance decreased, so that the ink density in the printing paper decreased. In the printing plate exposed with the same exposure amount, the printing durability was evaluated by the number of printed sheets when the ink density (reflection density) was reduced by 0.1 from the start of printing. In Tables 10, 11 and 12, the evaluation of printing durability was represented by the relative printing durability defined as follows, with Examples 1, 40 and 51 as the reference (1.0). The larger the relative printing durability number, the higher the printing durability.
Relative printing durability = (printing durability of the target lithographic printing plate precursor) / (printing durability of the standard lithographic printing plate precursor)

<Stain resistance>
The printed material on the 20th sheet was taken out after the start of printing, and the stain resistance was evaluated based on the ink density adhered to the non-image area. Ink adhesion in the non-image area does not necessarily occur uniformly, and thus is indicated by a visual evaluation score per 75 cm ² . The score for visual evaluation is 10 points when the ink adhesion area ratio of the non-image area is 0%, 9 points for 1-10%, 8 points for 11-20%, 7 points for 21-30%, 31-40 6 points, 41-50% 5 points, 51-60% 4 points, 61-70% 3 points, 71-80% 2 points, 81-90% 1 point, 91-100% The score was 0. The higher the score, the better the stain resistance.

<Stain resistance after aging>
After preparing a lithographic printing plate, it was left for 3 days in a constant temperature and humidity chamber set at 60 ° C. and a relative humidity of 60%. Using this printing plate, the stain resistance after the elapse of time was evaluated in the same manner as the above-described stain resistance evaluation. The higher the score, the better the stain resistance after aging.

<Developability>
The development processing was carried out while changing to various transport speeds, and the cyan density of the non-image area of the obtained lithographic printing plate was measured with a Macbeth densitometer. The transport speed at which the cyan density of the non-image area was equal to the cyan density of the aluminum support was determined and used as developability. In Tables 10, 11 and 12, the evaluation of developability was expressed as relative developability defined as follows, with Examples 1, 40 and 51 as the reference (1.0). The larger the value of the relative developability, the higher the developability and the better the performance.
Relative developability = (transport speed of target lithographic printing plate precursor) / (transport speed of reference lithographic printing plate precursor)

As is apparent from Tables 10 to 12, Comparative Examples 6 and 9 of the polymer consisting only of repeating units having a functional group that interacts with the surface of the support may have poor stain resistance and stain resistance after aging. I understand.
It can be seen that Comparative Examples 1, 3 to 5, 8, and 11 having no zwitterion in the side chain of the repeating unit are inferior in stain resistance, stain resistance after aging, and developability.
Comparative Examples 2, 7, and 10, which have zwitterions in the side chains of the repeating unit but do not have a specific linking group and do not satisfy the requirements of the general formulas (I) and (II), are poor in stain resistance and developability. I understand that.
On the other hand, Examples 1 to 63 having repeating units satisfying the requirements of the general formula (I) or (II) are excellent in stain resistance, stain resistance after aging and developability without impairing printing durability. I understand.

[Examples 64-85 and Comparative Examples 12-15]
[Exposure, development and printing]
Each lithographic printing plate precursor shown in Tables 13 and 14 is 50% under the conditions of output 9 W, outer drum rotation speed 210 rpm, resolution 2, 400 dpi using a Trendsetter 3244VX (equipped with water-cooled 40 W infrared semiconductor laser (830 nm)) manufactured by Creo. A flat screen image was exposed. Next, using the developing solution 1 or 4, in the automatic developing processor having the structure shown in FIG. 2, the heater setting at which the plate surface reaching temperature in the preheating part becomes 100 ° C., the immersion time (development time) in the developing solution is Development processing was performed at a conveyance speed of 20 seconds.

  The obtained lithographic printing plate is attached to a printing machine SOR-M manufactured by Heidelberg, and fountain solution (EU-3 (etch solution manufactured by FUJIFILM Corporation) / water / isopropyl alcohol = 1/89/10 (volume ratio). )) And TRANS-G (N) black ink (manufactured by Dainippon Ink & Chemicals, Inc.), printing was performed at a printing speed of 6000 sheets per hour.

  Each lithographic printing plate precursor was evaluated in the same manner as in Example 1 for printing durability, stain resistance, stain resistance after aging, and developability. Evaluation of printing durability and developability was performed in Tables 13 and 14 using Examples 64 and 75 as the reference (1.0), respectively. The results are shown in Tables 13 and 14.

As is apparent from Tables 13 and 14, Comparative Examples 12 and 14, which have a zwitterion in the side chain of the repeating unit but do not have a specific linking group and do not satisfy the requirements of the general formulas (I) and (II), It can also be seen that Comparative Examples 13 and 15 having no zwitterion in the side chain of the repeating unit are inferior in stain resistance, stain resistance after aging and developability.
On the other hand, Examples 64-85 having repeating units satisfying the requirements of the general formula (I) or (II) are excellent in stain resistance, stain resistance after aging and developability without impairing printing durability. I understand.

[Examples 86 to 96 and Comparative Examples 16 and 17]
[Exposure, development and printing]
Each lithographic printing plate precursor shown in Table 15 was exposed under the conditions of an external drum rotation speed of 1000 rpm, a laser output of 70%, and a resolution of 2400 dpi with a Luxel PLANETSETTER T-6000III equipped with an infrared semiconductor laser. The exposure image included a solid image and a 50% halftone dot chart of a 20 μm dot FM screen.
The exposed lithographic printing plate precursor was mounted on the plate cylinder of a printing machine LITHRONE 26 manufactured by Komori Corporation without developing. 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.) After supplying on the machine with dampening water and ink using the standard automatic printing start method of LITHRONE 26, printing was performed on Tohishi Art (76.5 kg) paper at a printing speed of 10,000 sheets per hour.

[Evaluation]
Each lithographic printing plate precursor was evaluated for on-press developability and printing durability as follows. The stain resistance and the stain resistance after aging were evaluated in the same manner as in Example 1. The results are shown in Table 15.
<On-press developability>
The number of print sheets required until the on-press development of the non-image portion of the image recording layer on the printing machine was completed and no ink was transferred to the non-image portion was measured as on-press developability.

<Print durability>
After the on-press development property was evaluated, printing was further continued. As the number of printed sheets increased, the image recording layer gradually worn out, so that the ink density on the printed material decreased. The printing durability is evaluated by assuming that the number of printed copies is the number of printed copies when the dot area ratio of the 50% halftone dot on the printed matter is 5% lower than the measured value of the 100th printed sheet. did. The evaluation of printing durability was expressed in terms of relative printing durability defined as follows using Example 86 as a reference (1.0). The larger the relative printing durability number, the higher the printing durability.
Relative printing durability = (printing durability of the target lithographic printing plate precursor) / (printing durability of the standard lithographic printing plate precursor)

As is apparent from Table 15, Comparative Example 16 having a zwitterion in the side chain of the repeating unit but having no specific linking group and not satisfying the requirements of the general formulas (I) and (II) and the side of the repeating unit It can be seen that Comparative Example 17 having no zwitterion in the chain is inferior in stain resistance, stain resistance after aging and on-press developability.
On the other hand, Examples 86 to 9 having repeating units satisfying the requirements of the general formula (I) or (II)
Is excellent in stain resistance, stain resistance after aging and on-press developability without impairing printing durability.

4: planographic printing plate precursor 6: developing unit 10: drying unit 16: transport roller 20: developing tank 22: transport roller 24: brush roller 26: squeeze roller 28: backup roller 36: guide roller 38: skewer roller

11: Transport path of planographic printing plate precursor 100: Automatic development processor 200: Preheating (preheating) unit 300: Developing unit 400: Drying unit 202: Machine frame 208: Heating chamber 210: Skewer roller 212: Carriage entrance 214: Heater 216: Circulation fan 218: Unloading port 304: Insertion roller pair 306: Processing tank 308: Developer tank

310: Outer panel 312: Slit insertion port 316: Submerged roller pair 318: Unloading roller pair 322: Brush roller pair 324: Shielding lid 326: Brush roller pair 330: Spray pipe 332: Partition plate 334: Slit insertion port 336: Liquid temperature sensor 338: Liquid level meter 332: Partition plate 342: Guide member 344: Guide roller 402: Support roller 404: Discharge port 406: Conveying roller pair 408: Conveying roller pair 410: Duct 412: Duct 414: Slit Hole 50: External tank 51: Overflow port 52: Upper liquid level meter 53: Lower liquid level meter 54: Filter unit 55: Developer supply pump C1: First circulation pipe C2: Second circulation pipe 71: Replenishment Water tank 72: Water replenishment pump C3: Third circulation pipe

Claims (22)

A lithographic printing plate precursor having a support and at least one layer including an image recording layer, wherein the layer in contact with the support among the at least one layer is represented by the following general formula (I) or (II) A lithographic printing plate precursor comprising a polymer (A) having a repeating unit (a1) having a partial structure represented by

(In general formula (I) or (II),
L ¹¹ and L ²¹ each independently represent a single bond or a divalent linking group, and X ⁺ represents -N ⁺ R ¹ R ^2- , -S ⁺ R ^1- , -I ⁺ -or -P ⁺ R ¹ R. ² - represents, a ^- is _{^{-SO 3 -, -CO 2 -,}} -PO 3 H - or -OPO ₃ H ^- represents a.
Y ⁺ represents ^{-N + R 3 R 4 R 5} , -S + R 3 R 4, -I + R 3 or ^{-P + R 3 R 4 R 5} .
R ¹ , R ² , R ³ , R ⁴ and R ⁵ each independently represents an alkyl group or an aryl group which may contain a hetero atom.
At least two of R ¹ , R ² and L ¹¹ , or at least two of R ¹ , R ² and L ¹² may be linked to each other to form a ring. At least two of R ³ , R ⁴ and L ²² may be connected to each other to form a ring.
L ¹² and L ²² each independently represents a divalent linking group containing an atom having at least one sp ² hybrid orbital or an sp hybrid orbital, or a divalent linking group containing at least one cyclic alkylene group. To express.
'Represents a site directly connected to the main chain. )   The lithographic printing according to claim 1, wherein the layer in contact with the support among the at least one layer is the image recording layer or an undercoat layer provided between the support and the image recording layer. Version original edition.   The lithographic printing plate precursor according to claim 1 or 2, wherein the polymer (A) is a polymer having a repeating unit having a partial structure represented by the general formula (I). The lithographic printing plate precursor as claimed in claim 1, wherein A ⁻ in the general formula (I) is —SO ₃ ^— or —CO ₂ ^— . X ^<+> in the said general formula (I) represents -N ^<+> R ^{< 1 >} R ^{< 2 >} -, Y ^<+> in general formula (II) represents -N ^<+> R ^{< 3 >} R ^{< 4 >} R ^{< 5 >.} The lithographic printing plate precursor described. L ^{12 in the} general formula (I) and L ²² in the general formula (II) each independently include at least a divalent group selected from the following group, which may include a hetero atom in the linking group. The lithographic printing plate precursor according to any one of claims 1 to 5, which is a divalent linking group containing one.

(In the above formula, * represents a linking site. R represents an alkyl group or a hydroxyl group.) L ^{12 in the} general formula (I) and L ²² in the general formula (II) each independently include at least a divalent group selected from the following group, which may include a hetero atom in the linking group. The lithographic printing plate precursor as claimed in claim 6, which is a divalent linking group containing one.

(In the above formula, * represents a linking site. R represents an alkyl group or a hydroxyl group.) In L ¹² in the general formula (I) and L ²² in the general formula (II), X ⁺ and A ⁻ or an oxygen atom directly connected to L ²² of the phosphate ester and Y ⁺ are used for linking. The lithographic printing plate precursor as claimed in any one of claims 1 to 7, wherein the shortest total number of atoms is 4 to 8.   The lithographic printing plate according to any one of claims 1 to 8, wherein the polymer (A) further comprises a repeating unit (a2) having at least one functional group that interacts with the surface of the support. Original edition.   10. The image recording layer according to claim 1, wherein the image recording layer further contains (B) a polymerization initiator, (C) a polymerizable compound, (D) a sensitizing dye, and (E) a binder polymer. Lithographic printing plate precursor.   The lithographic printing plate precursor according to claim 10, wherein the (E) binder polymer is a (meth) acrylic polymer, a polyurethane resin, or a polyvinyl butyral resin.   After the lithographic printing plate precursor according to any one of claims 1 to 11 is imagewise exposed, the image recording layer in a non-image area is removed in the presence of a developer having a pH of 2 to 14. A method for preparing a lithographic printing plate.   After the lithographic printing plate precursor according to any one of claims 1 to 11 is imagewise exposed, printing ink and fountain solution are supplied on a printing machine to remove the image recording layer portion of the non-image area. A method for producing a lithographic printing plate, comprising a step. A radical polymerizable unsaturated group-containing monomer represented by the following general formula (III) or (IV).

(In general formula (III) or (IV),
R ^X , R ^Y and R ^Z each independently represents a hydrogen atom or an alkyl group.
L ¹¹ and L ²¹ each independently represent a single bond or a divalent linking group, and X ⁺ represents -N ⁺ R ¹ R ^2- , -S ⁺ R ^1- , -I ⁺ -or -P ⁺ R ¹ R. ² - represents, a ^- is _{^{-SO 3 -, -CO 2 -,}} -PO 3 H - or -OPO ₃ H ^- represents a.
Y ⁺ represents ^{-N + R 3 R 4 R 5} , -S + R 3 R 4, -I + R 3 or ^{-P + R 3 R 4 R 5} .
R ¹ , R ² , R ³ , R ⁴ and R ⁵ each independently represents an alkyl group or an aryl group which may contain a hetero atom.
At least two of R ¹ , R ² and L ¹¹ , or at least two of R ¹ , R ² and L ¹² may be linked to each other to form a ring. At least two of R ³ , R ⁴ and L ²² may be connected to each other to form a ring.
L ¹² and L ²² each independently represents a divalent linking group containing an atom having at least one sp ² hybrid orbital or an sp hybrid orbital, or a divalent linking group containing at least one cyclic alkylene group. To express. )   The radically polymerizable unsaturated group containing monomer of Claim 14 represented by the said general formula (III). Formula (III) in the A ^- is, -SO ₃ ^- or -CO ₂ ^- and is a radical polymerizable unsaturated group-containing monomer according to claim 14 or 15. The radically polymerizable unsaturated group-containing monomer according to any one of claims 14 to 16, wherein X ⁺ in the general formula (III) is -N ⁺ R ¹ R ^2- . L ^{12 in the} general formula (III) and L ²² in the general formula (IV) each independently include at least a divalent group selected from the following group, which may include a hetero atom in the linking group. The radically polymerizable unsaturated group-containing monomer according to any one of claims 14 to 17, which is a divalent linking group containing one.

(In the above formula, * represents a linking site. R represents an alkyl group or a hydroxyl group.) L ^{12 in the} general formula (III) and L ²² in the general formula (IV) each independently include at least a divalent group selected from the following group, which may include a hetero atom in the linking group. The radical polymerizable unsaturated group-containing monomer according to claim 18, which is a divalent linking group containing one.

(In the above formula, * represents a linking site. R represents an alkyl group or a hydroxyl group.) In L ¹² of the general formula (III) and L ²² in the general formula (IV), X ⁺ and A ⁻ or an oxygen atom directly connected to L ²² of the phosphate ester and Y ⁺ are directly connected. The radically polymerizable unsaturated group-containing monomer according to any one of claims 14 to 19, wherein the shortest total number of atoms is 4 to 8. A polymer having a repeating unit (a1) having a partial structure represented by the following general formula (I) or (II).

(In general formula (I) or (II),
L ¹¹ and L ²¹ each independently represent a single bond or a divalent linking group, and X ⁺ represents -N ⁺ R ¹ R ^2- , -S ⁺ R ^1- , -I ⁺ -or -P ⁺ R ¹ R. ² - represents, a ^- is _{^{-SO 3 -, -CO 2 -,}} -PO 3 H - or -OPO ₃ H ^- represents a.
Y ⁺ represents ^{-N + R 3 R 4 R 5} , -S + R 3 R 4, -I + R 3 or ^{-P + R 3 R 4 R 5} .
R ¹ , R ² , R ³ , R ⁴ and R ⁵ each independently represents an alkyl group or an aryl group even if it contains a hetero atom.
At least two of R ¹ , R ² and L ¹¹ , or at least two of R ¹ , R ² and L ¹² may be linked to each other to form a ring. At least two of R ³ , R ⁴ and L ²² may be connected to each other to form a ring.
L ¹² and L ²² each independently represent a divalent linking group containing an atom having at least one sp ² hybrid orbital or an sp hybrid orbital, or a divalent linking group containing at least one cyclic alkylene. .
'Represents a site directly connected to the main chain. )   A hydrophilic film formed from the polymer according to claim 21.

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