JP2007230081A - Lithographic printing plate material and lithographic printing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a lithographic printing plate material with proper printability, excellent in stain removal properties, anti-scumming properties and halftone-dot reproducibility, and a lithographic printing method using the lithographic printing plate material. <P>SOLUTION: In this printing plate material which has an image forming function layer provided on an aluminum substrate and which enables development on a printing machine, the image forming function layer contains a photopolymerizable compound and a polymerization initiator; and a layer containing a compound expressed by general formula (1), (2), (3) or (4) is provided on the aluminum substrate side having the image forming function layer. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a lithographic printing plate material and a lithographic printing method, and more particularly to a lithographic printing plate material capable of image formation by a computer-to-plate (CTP) method and developable on a printing press, and a lithographic printing method using the same.

  With the digitization of print data, there is a need for CTP (computer-to-plate) technology that is inexpensive, easy to handle, and has the same printability as the PS plate.

  In recent years, in order to reduce the burden on the global environment, there is an increasing expectation for a so-called processless CTP printing plate that does not require a developer treatment with a special chemical. Among them, in recent years, after forming an image on a printing plate material, it can be mounted on a printing machine without being treated with chemicals, and unnecessary parts, so-called non-image parts can be removed with ink or fountain solution and printed immediately. A printing method using a less lithographic printing plate material (see Patent Document 1) has attracted attention.

  However, these processless lithographic printing plate materials have a problem that printing durability may not be sufficient. In order to solve the problem of poor printing durability in a printing method using a processless lithographic printing plate material, for example, studies have been made to solve the problem by using a polymerizable compound and a polymerization initiator (Patent Document 2). reference).

However, the problem that stain recovery is poor even when dampening water is supplied once the non-image area is dirty has not yet been solved. In addition, there is a problem that the halftone dot quality is not sufficient, the printed image quality is inferior, or the non-image area is smeared when imprinted, that is, the so-called anti-stain property is inferior. There was a strong demand.
JP-A-4-261539 JP 2002-287334 A

  An object of the present invention is to provide a lithographic printing plate material having excellent stain recovery properties and anti-staining properties, good printing suitability and excellent halftone dot reproducibility, and a lithographic printing method using the same.

The above object of the present invention is achieved by the following configurations.
1. A printing plate material that can be developed on a printing press having an image forming functional layer on an aluminum support, the image forming functional layer containing a photopolymerizable compound and a polymerization initiator, and the image forming of the aluminum support. A lithographic printing plate material comprising a layer containing a compound represented by the following general formula (1), (2), (3) or (4) on the side having a functional layer.

[Wherein, A ₁ and B ₁ represent a substituent. ]

Wherein, A ₂ and B ₂ represents a substituent. ]

[Wherein R ₁ and R ₂ represent a hydrogen atom or an alkyl group. A ₃ and B ₃ can completely overlap with the original group when rotated 180 ° around the axis connecting the bond point with the carbon atom indicated by C in the general formula and the line connecting the carbon atom. Represents a group. However, the sum of the hydroxyl groups of A ₃ and B ₃ is 0 or more and 1 or less. ]

[Wherein R ₃ and R ₄ represent a hydrogen atom or an alkyl group. A ₄ and B ₄ can completely overlap with the original group when rotated about 180 ° around the axis connecting the bond point with the carbon atom indicated by C in the general formula and the line connecting the carbon atom. Represents a group. However, the sum of the hydroxyl groups A ₄ and B ₄ have is 0 or more and 1 or less. ]
2. 2. The lithographic printing plate material according to 1, wherein the image-forming functional layer contains heat-fusible particles or heat-fusible particles.
3. The lithographic printing plate material according to 1 or 2, wherein the aluminum support has a hydrophilic surface.
4.1-3 After exposing the lithographic printing plate material according to any one of 1 to 3 to an image, the lithographic printing plate material is mounted on a printing machine, and dampening water and ink are supplied to the surface of the lithographic printing plate material to remove a non-image portion. A lithographic printing method comprising removing and printing.

  According to the above configuration of the present invention, it is possible to provide a lithographic printing plate material having good stain recovery properties and scumming prevention properties, excellent printing suitability and excellent halftone dot reproducibility, and a lithographic printing method using the same.

  The present invention relates to a printing plate material that can be developed on a printing press having an image forming functional layer on a support, the image forming functional layer containing a photopolymerizable compound and a polymerization initiator, and It is characterized by having a layer containing the compound represented by the general formula (1), (2), (3) or (4) on the side having the image forming functional layer.

  In particular, the image-forming functional layer contains a photopolymerizable compound, and by using the specific dye as a photothermal conversion agent, the stain recovery property and the anti-stain property are good, the printing property is excellent, and the network is excellent. A lithographic printing plate material excellent in point reproducibility can be provided.

(Compounds represented by general formulas (1), (2), (3) and (4))
First, the compound represented by the general formula (1) will be described. In the compound represented by the general formula (1), A ₁ and B ₁ represent substituents. Specific examples of A ₁ and B ₁ include an alkyl group, an alkenyl group, a cycloalkyl group, and an aryl group (for example, A phenyl group, a naphthyl group) and a heterocyclic group, preferably an alkenyl group, an aryl group (for example, a phenyl group, a naphthyl group) and a heterocyclic group.

  Furthermore, among the compounds represented by the general formula (1), a compound represented by the following general formula (11) is preferable.

In the formula, R ₃ , R ₆ , R ₇ and R ₁₀ are each independently hydrogen, an alkyl group having 1 to 20 carbon atoms, a cycloalkyl group having 1 to 20 carbon atoms, an aryl group having up to 14 carbon atoms, or an aralkyl. R ₄ , R ₅ , R ₈ and R ₉ are each independently hydrogen, an alkyl group having 1 to 20 carbon atoms, a cycloalkyl group having 1 to 20 carbon atoms, an aryl group having up to 14 carbon atoms, Aralkyl group or —CH ₂ OR ₁₁ [R ₁₁ is an alkylacyl group, —C (═O) R ₁₂ (R ₁₂ is an alkyl group having 1 to 20 carbon atoms), —SiR ₁₃ R ₁₄ R ₁₅ (R ₁₃ , R ₁₄ and R ₁₅ each independently represents an alkyl group having 1 to 20 carbon atoms.) Or —SO ₂ R ₁₆ (R ₁₆ is an alkyl group having 1 to 20 carbon atoms). More selected. Or at least one of R ₃ and R ₄ , R ₅ and R ₆ , R ₇ and R ₈ , R ₉ and R ₁₀ , R ₄ and R ₅ , R ₈ and R ₉ is bonded to each other. Form a 5-, 6- or 7-membered ring.

Here, the “alkyl group” is known not only to pure ring-opened and cyclic saturated hydrocarbon alkyl substituents (eg, methyl, ethyl, propyl, t-butyl, cyclohexyl, adamantyl, octadecyl, etc.) but also to those skilled in the art. Substituents (eg, hydroxyl, alkoxy, vinyl, phenyl, halogen atoms (F, Cl, Br, and I), cyano, nitro, amino, carboxyl, ether-containing groups (eg, CH ₃ CH ₂ OCH ₂ —)) Etc. are also included. The same applies to the aryl group.

Among these compounds, particularly preferred are those in which R ₃ , R ₆ , R ₇ and R ₁₀ are each independently hydrogen, and R ₄ , R ₅ , R ₈ and R ₉ are each independently Hydrogen, an alkyl group having 1 to 20 carbon atoms, a cycloalkyl group having 1 to 20 carbon atoms, an aryl group, or R ₄ and R ₅ and R ₈ and R ₉ are bonded to each other to form a 5-, 6-, or 7-membered ring. It is what forms.

Next, the compound represented by the general formula (2) will be described. In the compound represented by the general formula (2) according to the present invention, A ₂ and B ₂ represent substituents. Specific examples of A ₂ and B ₂ include an alkyl group, an alkenyl group, a cycloalkyl group, and an aryl group. Represents a group or a heterocyclic group, preferably an alkenyl group, an aryl group or a heterocyclic group.

Next, the compounds represented by general formula (3) and general formula (4) will be described. In the compounds represented by the general formula (3) and the general formula (4), A ₃ , B ₃ , A ₄ and B ₄ connect the carbon atom to the bonding point with the carbon atom indicated by C in the general formula. When the line is rotated 180 ° around the axis, it represents a group that can completely overlap the original group, but a monocyclic six-membered ring group that satisfies the requirements is preferred. The sum of the hydroxyl groups of A ₃ and B ₃ is 0 or more and 1 or less, and the sum of the hydroxyl groups of A ₄ and B ₄ is 0 or more and 1 or less, but preferably the sum of the hydroxyl groups is 0.

  The compounds represented by the general formulas (3) and (4) are preferably compounds represented by the following general formulas (5) and (6).

Wherein, R ₁ to R ₄ represents a hydrogen atom or an alkyl group. ZA ₃ , ZB ₃ , ZA ₄ and ZB ₄ represent an atomic group necessary for constructing a 6-membered heterocycle together with the carbon atom.

Next, the compounds represented by general formula (5) and general formula (6) will be described. In the formula, ZA ₃ , ZB ₃ , ZA ₄ , and ZB ₄ represent a group of atoms necessary for constructing a 6-membered heterocycle together with a carbon atom. As the constructed heterocycle, 1 heteroatom is included in the ring. It is preferably a monocyclic hetero 6-membered ring. A hetero atom is preferably a nitrogen atom or a sulfur atom.

  The compound having a squarylium nucleus is a compound having 1-cyclobuten-2-hydroxy-4-one in the molecular structure, and the compound having a croconium nucleus is 1-cyclopentene-2-hydroxy- in the molecular structure. It is a compound having 4,5-dione. Here, the hydroxy group may be dissociated.

  In the present invention, the squarylium nucleus and the croconium nucleus may use any structure as described below.

  In the present invention, exemplary compounds corresponding to the general formulas (1), (2), (3), and (4) are given serial numbers according to the respective general formulas, for example, (3) -12. It was described.

  Although the compound represented by General formula (11) used for this invention below is illustrated, this invention is not limited to these compounds.

According to another preferred embodiment, R ₅ and R ₆ , and R ₉ and R ₁₀ are bonded to each other to form a cycloalkyl group having 1 to 20 carbon atoms, R ₄ and R ₈ are aryl groups, ₃ and R ₇ are hydrogen. Preferred examples include the following.

According to a further preferred embodiment, R ₅ and R ₆ , and R ₉ and R ₁₀ are bonded to each other to form a lactam ring, R ₄ and R ₈ are alkyl groups or aryl groups, and R ₃ and R ₇ are Hydrogen. Representative compounds of this embodiment are shown below.

  Another preferred embodiment is a compound having the following structure.

In the formula, R is an alkyl group having 1 to 20 carbon atoms, preferably 4 to 20 carbon atoms. Examples of R include, but are not limited to, propyl, butyl, pentyl, octyl, —CH ₂ OCH ₂ CH ₃ , —CH ₂ OCH ₂ CH ₂ OCH _{3 and the} like.

In still another preferred embodiment, R ₃ , R ₆ , R ₇ and R ₁₀ as hydrogen are hydrogen, and R ₄ , R ₅ , R ₈ and R ₉ are —CH ₂ OR ₁₁ (R ₁₁ is —SiR). ₁₃ R ₁₄ R ₁₅ (R ₁₃ , R ₁₄ and R ₁₅ each independently represents an alkyl group having 1 to 20 carbon atoms) or —SO ₂ R ₁₆ (R ₁₆ is preferably 1 to 20 carbon atoms, preferably Is an alkyl group of 4 to 20))). Specifically, it is the following compound.

  The methods for synthesizing these compounds are described in Japanese Patent Publication No. 9-509503.

  The example of another preferable compound represented by General formula (1) is shown below.

  The example of another preferable compound represented by General formula (2) is shown below.

  Examples of the compounds represented by the general formulas (3) and (4) are shown below.

  Examples of other preferable compounds are listed below.

  These compounds can be synthesized by the method described in JP-A No. 2001-117201.

  In the present invention, these compounds (compounds represented by the general formulas (1) to (4)) function as a photothermal conversion agent and have a layer containing these compounds on the image forming functional layer side of the support.

  The layer containing these compounds may be an image forming functional layer or other layers.

  Examples of layers other than the image forming functional layer include a protective layer that can be provided on the image forming functional layer and a hydrophilic subbing layer formed on the aluminum support, but are adjacent to the image forming functional layer. It is preferable that

  In the present invention, infrared absorbing dyes and pigments other than the compound according to the present invention can be used in combination as a material that functions as a photothermal conversion agent.

  Examples of the pigment that can be used in combination include carbon, graphite, metal, and metal oxide.

  As carbon, furnace black or acetylene black is particularly preferable. The particle size (d50) is preferably 100 nm or less, and more preferably 50 nm or less.

  As the graphite, fine particles having a particle size of 0.5 μm or less, preferably 100 nm or less, more preferably 50 nm or less can be used.

  As the metal, any metal can be used as long as the particle diameter is 0.5 μm or less, preferably 100 nm or less, more preferably 50 nm or less. The shape may be any shape such as a spherical shape, a piece shape, or a needle shape. Colloidal metal fine particles (Ag, Au, etc.) are particularly preferable.

  As the metal oxide, a material exhibiting black in the visible light region is preferable, and as a material exhibiting black in the visible light region, metal oxide particles mainly composed of titanium oxide and iron oxide, or two or more kinds are used. And black composite metal oxides containing these metals. Specifically, the black composite metal oxide is a composite metal oxide composed of two or more metals selected from Al, Ti, Cr, Mn, Fe, Co, Ni, Cu, Zn, Sb, and Ba. In particular, a Cu—Cr—Mn or Cu—Fe—Mn composite metal oxide is preferable. These can be produced by the methods disclosed in JP-A-8-27393, 9-25126, 9-237570, 9-241529, and 10-231441.

  Preferred metal oxides are metal oxide particles mainly composed of titanium oxide and iron oxide, and more preferably metal oxide particles having a coercive force (HC) of 8 kA / m or less in a magnetic field of 400 kA / m. . Here, the coercive force (HC) is the magnitude of the reverse magnetic field that must be applied in order to flip the magnetizing polarity of the magnet.

  When the coercive force is large, in the coating liquid and coating material containing the particles, the particles are re-aggregated and are not easily formed into a uniform dispersion, and various problems are likely to occur. The coercive force (HC) is measured with a magnetometer, and can be measured using, for example, a vibrating sample magnetometer VSM-P7-15 manufactured by Toei Kogyo Co., Ltd. The coercive force (HC) of the preferred metal oxide particles is 8 kA / m or less in a magnetic field of 400 kA / m, more preferably 0 A / m or more and 6.5 kA / m or less, and even more preferably 0 A / m or more. 5 kA / m or less.

Specific examples of the metal oxide particles used include ilmenite (FeTiO ₃ ) particles, pseudo brookite (Fe ₂ TiO ₅ ) particles described in JP-A-1-298028, and pseudolites described in JP-A-3-2276. Particles having a mixed composition of brookite and hematite (Fe ₂ O ₃ ) -ilmenite (FeTiO ₃ ), an aqueous ferrous salt solution described in JP-A No. 2001-253717, an emulsion containing a hydrolyzable organic titanium compound and an emulsifier Iron-titanium composite oxide particles produced by spray pyrolysis using a spray pyrolysis solution, particles in which a rutile TiO ₂ phase substrate described in JP-A No. 2002-129063 is coated with an Fe ₂ TiO ₄ phase or JP be composite oxide composed mainly of Fe ₂ TiO ₄ according to 2005-68323 JP The total coating amount of Fe (II) and Fe (III) with respect to i is 150 to 300 atomic%, and Fe (II) with respect to the total amount of Fe (II) and Fe (III) is 0.50 or more. Particles having an L value of 9.0 or less are preferably used.

  The metal oxide particles are produced by the method described in the aforementioned published patent publication.

  These metal oxides preferably have an average primary particle size of 1 μm or less, and more preferably have an average primary particle size in the range of 0.01 to 0.8 μm. When the average primary particle size is 1 μm or less, the photothermal conversion ability with respect to the addition amount becomes better, and when the average primary particle size is within the range of 0.01 to 0.8 μm, the photothermal conversion ability with respect to the addition amount is obtained. Better. However, the photothermal conversion ability with respect to the addition amount is greatly affected by the degree of dispersion of the particles, and the better the dispersion, the better. Therefore, before adding these metal oxide particles to the coating solution for the layer, it is preferable to disperse them by a known method to prepare a dispersion (paste).

  An average primary particle size of less than 0.01 μm is not preferable because dispersion becomes difficult. A dispersing agent can be appropriately used for the dispersion. The addition amount of the dispersant is preferably 0.01 to 5% by mass, and more preferably 0.1 to 2% by mass with respect to the metal oxide particles. Although the kind of dispersing agent is not specifically limited, it is preferable to use various surfactants.

  Infrared absorbing dyes that can be used in combination include cyanine dyes, croconium dyes, polymethine dyes, azurenium dyes, thiopyrylium dyes, naphthoquinone dyes, anthraquinone dyes, and other organic compounds, phthalocyanine dyes, naphthalocyanine dyes, azo dyes , Thioamide-based, dithiol-based, and indoaniline-based organometallic complexes.

  Specifically, JP-A-63-139191, JP-A-64-33547, JP-A-1-160683, JP-A-280750, JP-A-1-293342, JP-A-2-2074, JP-A-3-26593, 3-30991, 3-34891, 3-36093, 3-36094, 3-36095, 3-42281, 3-97589, 3-103476, 7 -43851, 7-102179, and the compounds described in each publication. These can be used alone or in combination of two or more.

  As a particularly preferred embodiment of the photothermal conversion material, it is preferable to use a combination of the compound according to the present invention and a metal oxide pigment.

  As addition amount of a photothermal conversion agent, it is 0.1-50 mass% with respect to the layer containing this as a total amount of a photothermal conversion agent, 0.3-30 mass% is preferable, 0.5-20 mass% Is more preferable.

  Moreover, as content of the compound represented by General formula (1)-(4), 0.05 mass%-40 mass% are preferable with respect to the layer containing this, Especially 0.5 mass%-10 mass. % Is preferred.

(Image forming functional layer)
The lithographic printing plate material that can be developed on a printing press in the present invention is a printing plate material having an image forming functional layer that can be developed on a printing press.

  An image-forming layer that can be developed on a printing press means that after image exposure, a non-image part is removed by dampening water or dampening water and printing ink on a lithographic printing press without performing treatment with a special agent. Thus, the hydrophilic layer which is a non-image portion is exposed and can be formed into a printable printing plate.

  The image forming functional layer according to the present invention includes a photopolymerizable compound and a polymerization initiator.

(Photopolymerizable compound)
The photopolymerizable compound used in the present invention is a monomer / prepolymer having an ethylenically unsaturated bond that can be polymerized at least with active light.

  Examples of the photopolymerizable monomer / prepolymer include monofunctional acrylic acid esters such as 2-ethylhexyl acrylate, 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, and derivatives thereof, or acrylates thereof such as methacrylate, itaconate, crotonate, Compound substituted for maleate, etc., polyethylene glycol diacrylate, pentaerythritol diacrylate, bisphenol A diacrylate, bifunctional acrylic acid ester such as diacrylate of ε-caprolactone adduct of neopentyl glycol hydroxypivalate and its derivatives or their derivatives Compounds in which acrylate is replaced with methacrylate, itaconate, crotonate, maleate, etc., or trimethylolpropane tri (meth) a Examples include polyfunctional acrylic esters such as relates, dipentaerythritol pentaacrylate, dipentaerythritol hexaacrylate, pyrogallol triacrylate and derivatives thereof, or compounds in which these acrylates are replaced with methacrylate, itaconate, crotonate, maleate, etc. . As the resin having an ethylenically unsaturated bond, a so-called prepolymer in which acrylic acid or methacrylic acid is introduced into an oligomer having an appropriate molecular weight to impart polymerizability can be suitably used. Other preferable photopolymerizable compounds include compounds described in JP-A Nos. 61-6649 and 62-173295, compounds described in JP-A-2005-41206 (0085) to (0097), “11290 “Chemical Products”, Chemical Industry Daily, p. Compounds described in 286 to 294, “UV / EB Curing Handbook (raw material)”, Kobunshi Publishing Co., Ltd., p. The compounds described in 11 to 65 can be preferably used in the present invention.

(Polymerization initiator)
The polymerization initiator according to the present invention generates radicals by light and / or heat and initiates the curing reaction of the above-mentioned photopolymerization compound. In the present invention, since a photothermal conversion material is used together, a thermal polymerization initiator that decomposes by heat to generate radicals is preferably used.

  Examples of polymerization initiators according to the present invention include onium salts, triazine compounds having a halogen atom (such as triazine derivatives described in JP-B Nos. 59-1281, 61-9621, and JP-A-60-60104), iron arenes Complexes and bisimidazoles (2,4,5-triarylimidazole dimers described in JP-A Nos. 55-127550 and 60-202437, etc.) are preferably used.

  Examples of the onium salt include an iodonium salt, a sulfonium salt, a phossonium salt, a stannonium salt, an oxazolium salt, and the like, preferably represented by the following general formula (I), (II), (III), or (IV) A compound.

In the formula, R _{1 to} R ₄ and R _{10 to} R ₁₃ each represent an alkyl group, an aryl group, or an aralkyl group, and R _{1 to} R ₄ and R _{10 to} R ₁₃ are bonded to each other to form a ring. May be. R ₅ , R ₆ and R 7 each represents an alkyl group or an aryl group, and R _{5 to} R ₇ may be bonded to each other to form a ring. R ₈ and R ₉ each represents an aryl group, and X ⁻ represents a counter anion.

  First, the phosphonium salt compound represented by the general formula (I) (hereinafter referred to as the phosphonium salt of the present invention) will be described in detail.

  Specific examples of the substituent represented by R1 to R4 are as follows.

  Alkyl groups include straight-chain and branched alkyl groups such as methyl, ethyl, butyl, i-butyl, hexyl, octyl, stearyl groups and the like. From the viewpoint of color density, an alkyl group having 1 to 10 carbon atoms is preferable, and a butyl group is particularly preferable. These alkyl groups may be bonded to each other to form a ring, and the cycloalkyl group is preferably a 5- to 7-membered ring (for example, cyclopentyl, cyclohexyl group, etc.).

  Examples of the aryl group include phenyl and naphthyl groups, and examples of the aralkyl group include benzyl and phenethyl groups.

  These groups may be further substituted, and as a substituent, a halogen atom, a cyano group, a nitro group, an alkyl group, an aryl group, a hydroxyl group, an amino group (including an alkyl-substituted amino group), an alkoxy group, a carbamoyl group, -COOR group and -OCOR group (R is an organic group such as an alkyl group and an aryl group).

The counter anion represented by X ⁻ is not particularly limited as long as it is a monovalent anion, but is preferably a halogen ion, and chlorine and bromine anions are more desirable in terms of color density. Specific examples of the counter anion include bromide, chloride, iodide, fluoride, perchlorate, benzoate, thiocyanate, acetate, trifluoroacetate, hexafluorophosphate, nitrate, salicinate and the like.

  Next, the sulfonium salt compound represented by the general formula (II) (hereinafter referred to as the sulfonium salt of the present invention) will be described in detail.

Specific examples of the substituent represented by R _{5 to} R ₇ are as follows.

  Alkyl groups include linear and branched alkyl groups, and include methyl, ethyl, butyl, i-butyl, hexyl, octyl, stearyl groups and the like. From the viewpoint of color density, an alkyl group having 1 to 10 carbon atoms is preferable, and a butyl group is particularly preferable. These alkyl groups may be bonded to each other to form a ring, and the cycloalkyl group is preferably a 5- to 7-membered ring (for example, cyclopentyl, cyclohexyl group, etc.).

  Examples of the aryl group include phenyl and naphthyl.

Examples of the ring formed by combining R5 to R7 together with S ⁺ include a benzothiathiopyrylium ring.

  These groups may be further substituted, and examples of the substituent include the same groups as those described in the general formula (I).

X ^- counter anion represented by, X of the general Formulas (I) ^- is synonymous.

  Furthermore, the iodonium salt compound represented by the general formula (III) (hereinafter referred to as the iodonium salt of the present invention) will be described in detail.

Examples of the aryl group represented by R ₈ and R ₉ include phenyl and naphthyl groups. These groups may be further substituted, and examples of the substituent include the groups described in the general formula (I). The same group is mentioned.

X ^- counter anion represented by, X of the general Formulas (I) ^- is synonymous.

  Next, the ammonium salt compound represented by the general formula (IV) (hereinafter referred to as the ammonium salt of the present invention) will be described in detail.

Specific examples of the substituent represented by R _{10 to} R ₁₃ are as follows.

  Alkyl groups include straight-chain and branched alkyl groups such as methyl, ethyl, butyl, i-butyl, hexyl, octyl, stearyl and the like. From the viewpoint of color density, an alkyl group having 1 to 10 carbon atoms is preferable, and a butyl group is particularly preferable. These alkyl groups may be bonded to each other to form a ring, and the cycloalkyl group is preferably a 5- to 7-membered ring (for example, cyclopentyl, cyclohexyl group, etc.).

  Examples of the aryl group include phenyl and naphthyl groups, and examples of the aralkyl group include benzyl and phenethyl groups.

  These groups may be further substituted, and as a substituent, a halogen atom, cyano group, nitro group, alkyl group, aryl group, hydroxyl group, amino group (including alkyl-substituted amino group), alkoxy group, carbamoyl group , -COOR group, and -OCOR (wherein R represents an organic group such as an alkyl group or an aryl group).

  Although the typical example of the onium salt of this invention is given to the following, it is not limited to these.

  Other preferable onium salts include various oniums described in JP-B-55-39162, JP-A-59-14023, and “Macromolecules”, Vol. 10, page 1307 (1977). Compounds.

The addition amount of the onium salt of the present invention is preferably 0.2 to 5 g per 1 m ^{2 of} the image forming material, although it varies depending on the kind of onium salt and the usage form.

  Examples of the iron arene complex include the following structures.

In the formula, R ₁ represents an alkyl group, an aryl group or an alkoxy group.

  Compound QF-4 is preferred.

    Compound QF-4

  Moreover, it is preferable to use the thing of the following structure as a bisimidazole compound.

  Of these polymerization starting materials, onium salts are particularly preferred.

  These polymerization initiating materials can be used in combination with other radical generators for the purpose of further improving the sensitivity. Examples of radical generators that can be used in combination are described in JP-A Nos. 59-1504 and 61-243807. Organic peroxides described in JP-B Nos. 43-23684, 44-6413, 44-6413, 47-1604 and U.S. Pat. No. 3,567,453, U.S. Pat. , 848,328, 2,852,379 and 2,940,853, JP-B 36-22062, 37-13109, 38-18015, and 45- Ortho-quinonediazides described in 9610, azo compounds described in JP-A-59-142205, JP-A-1-54440, European Patent 109, 51, 126,712, Journal of Imaging Science (J. Imag. Sci.), Volume 30, page 174 (1986), other metal arene complexes, (Oxo) sulfonium organoboron complexes described in JP-A Nos. 4-56831 and 4-89535, titanocenes described in JP-A No. 61-151197, “Coordination Chemistry Review”, Vol. 84, 85-277 (1988) and transition metal complexes containing transition metals such as ruthenium described in JP-A-2-182701, carbon tetrabromide described in JP-A-3-209477, JP-A 59- And the organic halogen compounds described in No. 107344.

  The polymerization starting material used in the present invention preferably has a maximum absorption wavelength of 400 nm or less. More preferably, the maximum absorption wavelength is 360 nm or less, and most preferably 300 nm or less. By making the absorption wavelength in the ultraviolet region in this way, the lithographic printing plate precursor can be handled under white light.

  These polymerization starting materials may be used alone or in combination of two or more. Further, these polymerization initiators can be added to another layer in addition to the image forming functional layer.

  The image forming functional layer according to the present invention preferably contains heat-fusible particles or heat-fusible particles.

(Hot-melting particles)
The heat-meltable particles that can be used in the image-forming functional layer according to the present invention are particles that are formed of a material that has a low viscosity when melted, and is generally classified as a wax, among thermoplastic materials. .

  The physical properties are preferably a softening point of 40 ° C. or higher and 120 ° C. or lower, a melting point of 60 ° C. or higher and 150 ° C. or lower, in view of storage stability and ink inking property, a softening point of 40 ° C. or higher and 100 ° C. or lower, and a melting point of 60 ° C. or higher and 120 ° C. or lower. More preferably, it is not higher than ° C.

  Examples of materials that can be used include paraffin, polyolefin, polyethylene wax, microcrystalline wax, and fatty acid wax. These have a molecular weight of about 800 to 10,000, and in order to facilitate emulsification, these waxes can be oxidized to introduce polar groups such as a hydroxyl group, an ester group, a carboxyl group, an aldehyde group, and a peroxide group. Furthermore, in order to lower the softening point and improve workability, these waxes are used, for example, stearamide, linolenamide, laurylamide, myristamide, hardened bovine fatty acid amide, palmitoamide, oleic acid amide, rice sugar fatty acid amide. It is also possible to add coconut fatty acid amides or methylolated products of these fatty acid amides, methylene bisstellaramide, ethylene bisstellaramide and the like. Coumarone-indene resin, rosin-modified phenol resin, terpene-modified phenol resin, xylene resin, ketone resin, acrylic resin, ionomer, and copolymers of these resins can also be used.

  Among these, it is preferable to contain any of polyethylene, microcrystalline, fatty acid ester, and fatty acid. Since these materials have a relatively low melting point and a low melt viscosity, high-sensitivity image formation can be performed. Further, since these materials have lubricity, damage when a shearing force is applied to the surface of the printing plate material is reduced, and resistance to printing stains due to scratches or the like is improved.

  These heat-meltable particles are preferably dispersible in water, and the average particle diameter is preferably 0.01 to 10 μm, more preferably 0.05 to 3 μm from the viewpoint of on-press developability. .

  In order to disperse these heat-meltable particles in water, it is preferable to use a nonionic surfactant, an anionic surfactant, a cationic surfactant, or a polymer surfactant. By using these compounds, it is possible to stabilize an aqueous dispersion of heat-meltable fine particles and to obtain a uniform coated product free from failure.

  Further, the composition of the heat-meltable particles may be continuously changed between the inside and the surface layer, or may be coated with a different material. As a coating method, a known microcapsule formation method, a sol-gel method, or the like can be used.

  As content of the heat-meltable particle | grains in a structure layer, 1-90 mass% of the whole layer is preferable, and 5-80 mass% is still more preferable.

(Heat-bonding particles)
Examples of the heat-fusible particles include thermoplastic hydrophobic polymer particles, and there is no specific upper limit for the softening temperature of the thermoplastic hydrophobic polymer particles. It is preferable that the temperature is lower than the decomposition temperature. Moreover, it is preferable that the weight average molecular weight (Mw) of a high molecular weight polymer is the range of 10,000-1,000,000.

  Specific examples of the polymer constituting the thermoplastic hydrophobic polymer particles include, for example, diene (co) polymers such as polypropylene, polybutadiene, polyisoprene, and ethylene-butadiene copolymer, and styrene-butadiene. Synthetic rubbers such as copolymer, methyl methacrylate-butadiene copolymer, acrylonitrile-butadiene copolymer, polymethyl methacrylate, methyl methacrylate- (2-ethylhexyl acrylate) copolymer, methyl methacrylate-methacrylic acid copolymer, Methyl acrylate- (N-methylolacrylamide) copolymer, (meth) acrylic acid ester such as polyacrylonitrile, (meth) acrylic acid (co) polymer, polyvinyl acetate, vinyl acetate-vinyl propionate copolymer, acetic acid Vinyl-ethylene copolymer weight Vinyl ester (co) polymer such as a body, vinyl acetate - (2-ethylhexyl acrylate) copolymers, polyvinyl chloride, polyvinylidene chloride, polystyrene and copolymers thereof. Of these, (meth) acrylic acid esters, (meth) acrylic acid (co) polymers, vinyl ester (co) polymers, polystyrene, and synthetic rubbers are preferably used.

  The thermoplastic hydrophobic polymer particles may be made of a polymer polymer polymerized by any known method such as an emulsion polymerization method, a suspension polymerization method, a solution polymerization method, or a gas phase polymerization method. As a method for making a polymer polymer polymerized by a solution polymerization method or a gas phase polymerization method into a fine particle, a solution is sprayed in an inert gas in an organic solvent of the polymer polymer and dried to make a fine particle, Examples include a method in which a high molecular polymer is dissolved in an organic solvent immiscible with water, this solution is dispersed in water or an aqueous medium, and the organic solvent is distilled off to form fine particles.

  In any of the methods, the heat-meltable particles and the heat-fusible particles may be used as a dispersant or a stabilizer for polymerization or micronization, if necessary, such as sodium lauryl sulfate, sodium dodecylbenzenesulfonate, polyethylene glycol, etc. Alternatively, a water-soluble resin such as a surfactant or polyvinyl alcohol may be used. Further, triethylamine, triethanolamine or the like may be contained.

  The heat-fusible particles are preferably dispersible in water, and the average particle diameter is preferably 0.01 to 10 μm, more preferably 0.1 to 10 μm from the viewpoint of on-press developability and resolution. 3 μm.

  Further, the composition of the heat fusible particles may be continuously changed between the inside and the surface layer, or may be coated with a different material. As a coating method, a known microcapsule formation method, a sol-gel method, or the like can be used.

  As content of the heat-fusible particle | grains in a structural layer, 1-90 mass% of the whole layer is preferable, and 5-80 mass% is still more preferable.

(Binder polymer)
The image recording layer according to the present invention may contain a binder polymer in order to improve film properties and on-press developability. A conventionally well-known thing can be used as a binder polymer without a restriction | limiting, The linear organic polymer which has film property is preferable. Examples of such binder polymers include acrylic resins, polyvinyl acetal resins, polyurethane resins, polyurea resins, polyimide resins, polyamide resins, epoxy resins, methacrylic resins, polystyrene resins, novolac phenolic resins, polyester resins, and synthetic rubbers. And natural rubber.

  The binder polymer preferably has crosslinkability in order to improve the film strength of the image area. In order to impart crosslinkability to the binder polymer, a crosslinkable functional group such as an ethylenically unsaturated bond may be introduced into the main chain or side chain of the polymer. The crosslinkable functional group may be introduced by copolymerization or may be introduced by a polymer reaction.

  Examples of the polymer having an ethylenically unsaturated bond in the main chain of the molecule include poly-1,4-butadiene and poly-1,4-isoprene.

  Examples of polymers having an ethylenically unsaturated bond in the side chain of the molecule are polymers of esters or amides of acrylic acid or methacrylic acid, of the ester or amide residues (R of -COOR or -CONHR) Mention may be made of polymers having at least partly ethylenically unsaturated bonds.

Examples of the residue (the R) having an ethylenically unsaturated _{bond, - (CH 2) nCR 1} = CR 2 R 3, - (CH 2 O) nCH 2 CR 1 = CR 2 R 3, - (CH _{2 CH 2 O) nCH 2 CR} 1 = CR 2 R 3, - (CH 2) nNH-CO-O-CH 2 CR 1 = CR 2 R 3, - (CH 2) n-O-CO-CR 1 = CR ₂ R ₃ and — (CH ₂ CH ₂ O) ₂ —X (wherein R _{1 to} R ₃ are each a hydrogen atom, a halogen atom, or an alkyl group having 1 to 20 carbon atoms, an aryl group, an alkoxy group, or an aryl group. Represents an oxy group, and R ₁ and R ₂ or R ₃ may combine with each other to form a ring, n represents an integer of 1 to 10. X represents a dicyclopentadienyl residue. .).

Specific examples of the ester residue include —CH ₂ CH═CH ₂ , —CH ₂ CH ₂ O—CH ₂ CH═CH ₂ , —CH ₂ C (CH ₃ ) ═CH ₂ , —CH ₂ CH═CH— _{C 6 H 5, -CH 2 CH} 2 OCOCH = CH-C 6 H 5, -CH 2 CH 2 OCOC (CH 3) = CH 2, -CH 2 CH 2 OCOCH = CH 2, -CH 2 CH 2 -NHCOO (wherein, X represents a dicyclopentadienyl residue.) -CH ₂ CH = CH ₂ and -CH ₂ CH ₂ O-X and the like.

Specific examples of the amide residue include —CH ₂ CH═CH ₂ , —CH ₂ CH ₂ —Y (wherein Y represents a cyclohexene residue), —CH ₂ CH ₂ —OCO—CH═CH _2. Is mentioned.

  In the case of a binder polymer having crosslinkability, for example, free radicals (polymerization initiation radicals or growth radicals in the polymerization process of a polymerizable compound) are added to the crosslinkable functional group, and a polymerization chain of a polymerizable compound is formed directly between polymers. Through addition polymerization, 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 to each other so that crosslinking between the polymer molecules occurs. Forms and cures.

  The content of the crosslinkable group in the binder polymer (content of unsaturated double bond capable of radical polymerization by iodine titration) is preferably 0.1 to 10.0 mmol, more preferably 1.0, per 1 g of the binder polymer. -7.0 mmol, most preferably 2.0-5.5 mmol. Within this range, good sensitivity and good storage stability can be obtained.

  From the viewpoint of improving the on-press developability of the unexposed area of the image forming layer, the binder polymer preferably has high solubility or dispersibility in ink and / or fountain solution.

  In order to improve solubility or dispersibility in ink, the binder polymer is preferably oleophilic, and in order to improve solubility or dispersibility in dampening water, the binder polymer is hydrophilic. Is preferred. For this reason, in the present invention, it is also effective to use a lipophilic binder polymer and a hydrophilic binder polymer in combination.

  Examples of hydrophilic binder polymers include hydroxy groups, carboxyl groups, carboxylate groups, hydroxyethyl groups, polyoxyethyl groups, hydroxypropyl groups, polyoxypropyl groups, amino groups, aminoethyl groups, aminopropyl groups, and ammonium. Preferred are those having a hydrophilic group such as a group, an amide group, a carboxymethyl group, a sulfonic acid group, and a phosphoric acid group.

  Specific examples include gum arabic, casein, gelatin, starch derivatives, carboxymethylcellulose and its sodium salt, cellulose acetate, sodium alginate, vinyl acetate-maleic acid copolymers, styrene-maleic acid copolymers, polyacrylic acids and their salts, Polymethacrylic acids and their salts, homopolymers and copolymers of hydroxyethyl methacrylate, homopolymers and copolymers of hydroxyethyl acrylate, homopolymers and copolymers of hydroxypropyl methacrylate, homopolymers and copolymers of hydroxypropyl acrylate, homopolymers of hydroxybutyl methacrylate Polymers and copolymers, homopolymers and copolymers of hydroxybutyl acrylate Polyethylene glycols, hydroxypropylene polymers, polyvinyl alcohols, hydrolyzed polyvinyl acetate, polyvinyl formal, polyvinyl butyral, polyvinyl pyrrolidone, acrylamide homopolymers and copolymers having a hydrolysis degree of 60% by mass or more, preferably 80% by mass or more , Homopolymers and polymers of methacrylamide, homopolymers and copolymers of N-methylolacrylamide, polyvinylpyrrolidone, alcohol-soluble nylon, polyether of 2,2-bis- (4-hydroxyphenyl) -propane and epichlorohydrin, etc. Is mentioned.

  The binder polymer preferably has a weight average molecular weight of 5000 or more, more preferably 10,000 to 300,000, and a number average molecular weight of 1,000 or more, preferably 2000 to 250,000. More preferred. The polydispersity (weight average molecular weight / number average molecular weight) is preferably 1.1 to 10.

  The binder polymer may be any of a random polymer, a block polymer, a graft polymer, and the like, but is preferably a random polymer.

  The binder polymer can be synthesized by a conventionally known method. Especially, the binder polymer which has a crosslinkable group in a side chain can be easily synthesized by radical polymerization or polymer reaction. As the radical polymerization initiator used for radical polymerization, known compounds such as azo initiators and peroxide initiators can be used. Examples of the solvent used in the synthesis include tetrahydrofuran, ethylene dichloride, cyclohexanone, methyl ethyl ketone, acetone, methanol, ethanol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, 2-methoxyethyl acetate, diethylene glycol dimethyl ether, 1-methoxy. Examples include 2-propanol, 1-methoxy-2-propyl acetate, N, N-dimethylformamide, N, N-dimethylacetamide, toluene, ethyl acetate, methyl lactate, ethyl lactate, dimethyl sulfoxide, and water. These may be used alone or in combination of two or more.

  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 10 to 90% by mass, more preferably 20 to 80% by mass, and 30 to 70% by mass with respect to the total solid content of the image forming functional layer. Is more preferable. Within this range, good image area strength and image formability can be obtained.

  Moreover, it is preferable to use a polymeric compound and a binder polymer in the quantity used as 1 / 9-7 / 3 by mass ratio.

(Support)
Next, the aluminum support according to the present invention will be described. As the aluminum support that can be used in the present invention, an aluminum substrate made of aluminum or an aluminum alloy (hereinafter also referred to as aluminum) is used from the relationship between specific gravity and rigidity.

  Various aluminum alloys can be used. For example, an alloy of a metal such as silicon, copper, manganese, magnesium, chromium, zinc, lead, bismuth, nickel, titanium, sodium, iron, and aluminum is used. The thickness of the aluminum substrate is not particularly limited as long as it can be attached to a printing press, but a thickness of 50 to 500 μm is generally easy to handle.

  The aluminum substrate used in the present invention is more preferably one that has been subjected to any of the known roughening treatment, anodizing treatment, or surface hydrophilization treatment, that is, aluminum grain. The aluminum grain may be produced by any method, but one of the production methods for obtaining the surface shape defined in the present invention is the method disclosed in JP-A-10-869. Can do.

  Prior to roughening (graining treatment), the aluminum base material is preferably subjected to a degreasing treatment in order to remove the rolling oil on the surface. As the degreasing treatment, a degreasing treatment using a solvent such as trichlene or thinner, an emulsion degreasing treatment using an emulsion such as kesilon or triethanol, or the like is used.

  In addition, an alkaline aqueous solution such as caustic soda can be used for the degreasing treatment. When an alkaline aqueous solution such as caustic soda is used for the degreasing treatment, dirt and oxide film that cannot be removed only by the degreasing treatment can be removed. When an alkaline aqueous solution such as caustic soda is used for the degreasing treatment, smut is generated on the surface of the aluminum base material. In this case, it is immersed in an acid such as phosphoric acid, nitric acid, sulfuric acid, chromic acid, or a mixed acid thereof. It is preferable to perform a desmut treatment.

Examples of the roughening method include a mechanical method and a method of etching by electrolysis. The mechanical roughening method used is not particularly limited, but a brush polishing method and a honing polishing method are preferable. The roughening by the brush polishing method is, for example, by rotating a rotating brush using brush bristles having a diameter of 0.2 to 0.8 mm, and watering, for example, volcanic ash particles having a particle size of 10 to 100 μm on the surface of the aluminum substrate. While supplying the slurry dispersed uniformly, the brush can be pressed. The roughening by honing polishing is performed by, for example, uniformly dispersing volcanic ash particles having a particle size of 10 to 100 μm in water, injecting the pressure from a nozzle and injecting it obliquely to the surface of the aluminum base material. be able to. Also, for example, abrasive particles having a particle diameter of 10 to 100 μm are present on the surface of the aluminum substrate at a density of 2.5 × 10 ³ to 10 × 10 ³ particles / cm ² at intervals of 100 to 200 μm. Roughening can also be performed by laminating the coated sheets and transferring the rough surface pattern of the sheet by applying pressure.

After roughening by the above-mentioned mechanical roughening method, it is preferable to immerse in an aqueous solution of acid or alkali in order to remove the abrasive that has digged into the surface of the aluminum substrate, formed aluminum scraps and the like. Examples of the acid include sulfuric acid, persulfuric acid, hydrofluoric acid, phosphoric acid, nitric acid, hydrochloric acid, and the like. Examples of the base include sodium hydroxide and potassium hydroxide. Among these, it is preferable to use an aqueous alkali solution such as sodium hydroxide. The dissolution amount of aluminum in the support surface, 0.5 to 5 g / m ² is preferred. After the immersion treatment with an alkaline aqueous solution, it is preferable to carry out a neutralization treatment by immersion in an acid such as phosphoric acid, nitric acid, sulfuric acid, chromic acid or a mixed acid thereof.

The electrochemical surface roughening method is not particularly limited, but a method of electrochemical surface roughening in an acidic electrolyte is preferable. As the acidic electrolytic solution, an acidic electrolytic solution usually used in an electrochemical surface roughening method can be used, but a hydrochloric acid-based or nitric acid-based electrolytic solution is preferably used. As the electrochemical surface roughening method, for example, methods described in Japanese Patent Publication No. 48-28123, British Patent No. 896,563 and Japanese Patent Laid-Open No. 53-67507 can be used. This roughening method can be generally performed by applying a voltage in the range of 1 to 50 volts, but is preferably selected from the range of 10 to 30 volts. Current density may be in the range of 10 to 200 A / dm ^2, preferably selected from the range of 50 to 150 A / dm ^2. The quantity of electricity, may be in the range of 5000 C / dm ^2, preferably selected from the range of 100~2000c / dm ^2. The temperature at which the roughening method is performed can be in the range of 10 to 50 ° C, but is preferably selected from the range of 15 to 45 ° C.

When electrochemical surface roughening is performed using a nitric acid-based electrolyte as the electrolyte, it can be generally performed by applying a voltage in the range of 1 to 50 volts, but is selected from the range of 10 to 30 volts. Is preferred. Current density may be in the range of 10 to 200 A / dm ^2, preferably selected from the range of 20 to 100 A / dm ^2. The quantity of electricity, may be in the range of 5000 C / dm ^2, preferably selected from the range of 100~2000c / dm ^2. The temperature at which the electrochemical roughening method is performed can be in the range of 10 to 50 ° C, but is preferably selected from the range of 15 to 45 ° C. The concentration of nitric acid in the electrolytic solution is preferably 0.1 to 5% by mass. If necessary, nitrates, chlorides, amines, aldehydes, phosphoric acid, chromic acid, boric acid, acetic acid, oxalic acid, and the like can be added to the electrolytic solution.

When a hydrochloric acid-based electrolyte is used as the electrolyte, it can be generally applied by applying a voltage in the range of 1 to 50 volts, but is preferably selected from the range of 2 to 30 volts. Current density may be in the range of 10 to 200 A / dm ^2, preferably selected from the range of 50 to 150 A / dm ^2. The quantity of electricity, may be in the range of ^{100~5000c / dm 2, 100~2000c / dm} 2, and more preferably selected from the range of 200~1000c / dm ^2. The temperature at which the electrochemical roughening method is performed can be in the range of 10 to 50 ° C, but is preferably selected from the range of 15 to 45 ° C. The concentration of hydrochloric acid in the electrolytic solution is preferably 0.1 to 5% by mass.

After the surface is roughened by the electrochemical surface roughening method, it is preferably immersed in an acid or alkali aqueous solution in order to remove aluminum scraps on the surface. Examples of the acid include sulfuric acid, persulfuric acid, hydrofluoric acid, phosphoric acid, nitric acid, hydrochloric acid, and the like. Examples of the base include sodium hydroxide and potassium hydroxide. Among these, it is preferable to use an alkaline aqueous solution. The dissolution amount of aluminum in the support surface, 0.5 to 5 g / m ² is preferred. In addition, it is preferable that after the immersion treatment with an alkaline aqueous solution, neutralization treatment is performed by immersion in an acid such as phosphoric acid, nitric acid, sulfuric acid, chromic acid or a mixed acid thereof.

  The mechanical surface roughening method and the electrochemical surface roughening method may each be used alone for roughing, or the mechanical surface roughening method followed by the electrochemical surface roughening method. You may roughen.

Following the roughening treatment, anodizing treatment is preferably performed. There is no restriction | limiting in particular in the method of the anodizing process which can be used in this invention, A well-known method can be used. By performing the anodizing treatment, an oxide film is formed on the aluminum substrate. For the anodizing treatment, a method of electrolyzing an aqueous solution containing sulfuric acid and / or phosphoric acid at a concentration of 10 to 50% as an electrolytic solution at a current density of 1 to 10 A / dm ² is preferably used. A method of electrolysis at a high current density in sulfuric acid described in Japanese Patent No. 1,412,768, a method of electrolysis using phosphoric acid described in US Pat. No. 3,511,661, chromium Examples thereof include a method using a solution containing one or more acids, oxalic acid, malonic acid and the like. The formed anodic oxidation coating amount is suitably 1 to 50 mg / dm ² , preferably 10 to 40 mg / dm ² . The anodized coating amount is obtained by, for example, immersing an aluminum plate in a chromic phosphate solution (85% phosphoric acid solution: 35 ml, prepared by dissolving 20 g of chromium (IV) oxide in 1 L of water) to dissolve the oxide film, It is obtained from mass change measurement before and after dissolution of the coating on the plate.

  The anodized aluminum base material may be subjected to sealing treatment as necessary. These sealing treatments can be performed using known methods such as hot water treatment, boiling water treatment, water vapor treatment, sodium silicate treatment, dichromate aqueous solution treatment, nitrite treatment, and ammonium acetate treatment.

  Further, after these treatments, as a hydrophilization treatment, a water-soluble resin such as polyvinylphosphonic acid, a polymer or copolymer having a sulfonic acid group in the side chain, polyacrylic acid, a water-soluble metal salt ( For example, zinc borate) or a dye obtained by subtracting yellow dye, amine salt or the like is also suitable. Further, a sol-gel treated substrate in which a functional group capable of causing an addition reaction by a radical as disclosed in JP-A No. 5-304358 is covalently used.

(Undercoat layer on aluminum support)
In this invention, it is preferable to have an undercoat layer containing a compound represented by the following general formula (A) on the aluminum support.

R ¹ , R ² and R ³ are each independently a hydrogen atom, a halogen atom or an alkyl group having 1 to 6 carbon atoms; X is an oxygen atom or imino, and L is a divalent linkage. And A is a functional group that is adsorptive to the support surface.

In the general formula (A), R ¹ , R ² and R ³ are each independently a hydrogen atom, a halogen atom or an alkyl group having 1 to 6 carbon atoms. R ¹ , R ² and R ³ are preferably each independently a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, and preferably a hydrogen atom or an alkyl group having 1 to 3 carbon atoms. More preferred is a hydrogen atom or methyl. R ¹ and R ² are particularly preferably a hydrogen atom.

  In general formula (A), X is an oxygen atom (—O—) or imino (—NH—). X is more preferably an oxygen atom.

  In the general formula (A), L is a divalent linking group. L is a divalent aliphatic group (alkylene group, substituted alkylene group, alkenylene group, substituted alkenylene group, alkynylene group, substituted alkynylene group), divalent aromatic group (arylene group, substituted arylene group) or divalent Or an oxygen atom (—O—), a sulfur atom (—S—), an imino (—NH—), a substituted imino (—NR—), and R is an (aliphatic group, aromatic Group or heterocyclic group) or a combination with carbonyl (—CO—).

  The aliphatic group may have a cyclic structure or a branched structure. The number of carbon atoms in the aliphatic group is preferably 1 to 20, more preferably 1 to 15, and most preferably 1 to 10. The aliphatic group is preferably a saturated aliphatic group rather than an unsaturated aliphatic group. The aliphatic group may have a substituent. Examples of the substituent include a halogen atom, a hydroxyl group, an aromatic group, and a heterocyclic group.

  The number of carbon atoms in the aromatic group is preferably 6 to 20, more preferably 6 to 15, and most preferably 6 to 10. The aromatic group may have a substituent. Examples of the substituent include a halogen atom, a hydroxyl group, an aliphatic group, an aromatic group, and a heterocyclic group.

  The heterocyclic group preferably has a 5-membered or 6-membered ring as the heterocycle. The heterocycle may be condensed with other heterocycles, aliphatic rings or aromatic rings. The heterocyclic group may have a substituent. Examples of the substituent include a halogen atom, hydroxyl, oxo (═O), thiooxo (═S), imino (═NH), substituted imino group (═N—R, R is an aliphatic group, aromatic group or hetero group. Ring group), aliphatic group, aromatic group and heterocyclic group.

L is preferably a divalent linking group containing a plurality of polyoxyalkylene structures. The polyoxyalkylene structure is more preferably a polyoxyethylene structure. That, L _{is, - (OCH 2 CH 2)} n- (n is an integer of 2 or more) preferably contains.

  In the general formula (A), A is a functional group having an adsorptivity on the surface of the support, for example, a metal, a metal oxide or a hydroxyl group present on the support subjected to an anodizing treatment or a hydrophilization treatment; It is preferably a group causing an ionic bond, a hydrogen bond, a coordination bond or a bond due to intermolecular force, and the functional group is preferably an acid group or an onium group.

The acid group preferably has an acid dissociation constant (pKa) of 7 or less. Examples of acid groups are phenolic hydroxyl groups (—OH), carboxylic acid groups (—COOH), sulfonic acid groups (—SO ₃ H), sulfate ester groups (—OSO ₃ H), phosphonic acid groups (—PO ₃ H). ₂ ), phosphoric acid group (—OPO ₃ H ₂ ), phosphoric acid amide group (—NH—PO ₃ H ₂ ), —CONHSO ₂ —, —SO ₂ NHSO ₂ — and —COCH ₂ COCH ₃ . Carboxylic acid groups, phosphonic acid groups, phosphoric acid groups and phosphoric acid amide groups are preferred.

  The onium group is preferably an onium group comprising an atom of Group 5B (Group 15) or Group 6B (Group 16) of the periodic table, more preferably an onium group comprising a nitrogen atom, a phosphorus atom or a sulfur atom, and from the nitrogen atom. The onium group is most preferred.

  By blocking the functional group with a protecting group, the compound of the general formula (A) can be converted into a precursor. For example, when the functional group is an acid group, the compound of the general formula (A) can be converted into a precursor by esterifying the acid. An undercoat layer may be provided using these precursors.

  Although the example of a compound represented by general formula (A) is shown below, it is not limited to these.

[A-1]
_{CH 2 = C (CH 3)} COO (C 2 H 4 O) nP = O (OH) 2
n = 1;
Unichemical Co., Ltd .; Phosmer M,
Nippon Kayaku Co., Ltd .; Kayamar PM-1
Kyoeisha Yushi Co., Ltd .; Light Ester PM
Shin Nakamura Chemical Co., Ltd .; NK Ester SA,
[A-2]
n = 2; Unichemical Co., Ltd .; Phosmer PE2,
[A-3]
n = 4-5; Unichemical Co., Ltd .; Phosmer PE,
[A-4]
n = 8; Unichemical Co., Ltd .; Phosmer PE8,
_{[A-5] [CH 2} = C (CH 3) COO (C 2 H 4 O) n] m P = O (OH) 3-m
n = 1, a mixture of m = 1 and 2; Daihachi Chemical Co., Ltd .; MR-200,
_{[A-6] CH 2 =} CHCOO (C 2 H 4 O) nP = O (OH) 2
n = 1; Unichemical Co., Ltd .; Phosmer A, Kyoeisha Yushi Co., Ltd .; Light Ester PA,
_{[A-7] [CH 2} = CHCOO (C 2 H 4 O) n] mP = O (OH) 3-m
n = 1, a mixture of m = 1 and 2; Daihachi Chemical Co., Ltd .; AR-200,
_{[A-8] CH 2 =} C (CH 3) COO (C 2 H 4 O) nP = O (OC 4 H 9) 2
n = 1; Daihachi Chemical Co., Ltd .; MR-204,
_{[A-9] CH 2 =} CHCOO (C 2 H 4 O) nP = O (OC 4 H 9) 2
n = 1; Daihachi Chemical Co., Ltd .; AR-204,
_{[A-10] CH 2 =} C (CH) COO (C 2 H 4 O) nP = O (OC 8 H 17) 2
n = 1; Daihachi Chemical Co., Ltd .; MR-208,
_{[A-11] CH 2 =} CHCOO (C 2 H 4 O) nP = O (OC 8 H 17) 2
n = 1; Daihachi Chemical Co., Ltd .; AR-208,
[A-12]
Unichemical Co., Ltd .; Phosmer MH,

_{[A-13] CH 2 =} C (CH 3) COO (C 2 H 4 O) n P = O (OH) (ONH (CH 3) 2 C 2 H 4 OCOC (CH 3) = CH 2)
n = 1; Unichemical Co., Ltd .; Phosmer DM,
_{[A-14] CH 2 =} C (CH 3) COO (C 2 H 4 O) n P = O (OH) (ONH (C 2 H 5) 2 C 2 H 4 OCOC (CH 3) = CH 2)
n = 1; Unichemical Co., Ltd .; Phosmer DE,
_{[A-15] CH 2 =} CHCOO (C 2 H 4 O) nP = O (O-ph) 2 (ph: benzene ring)
n = 1; Daihachi Chemical Co., Ltd .; AR-260,
_{[A-16] CH 2 =} C (CH) COO (C 2 H 4 O) nP = O (O-ph) 2
n = 1; Daihachi Chemical Co., Ltd .; MR-260,
[A-17] CH = CHCOO (C 2 H 4 O) n 2 P = O (OC 4 H 9)
n = 1; Daihachi Chemical Co., Ltd .; PS-A4,
_{[A-18] [CH 2} = C (CH 3) COO (C 2 H 4 O) n] 2 P = O (OH)
n = 1; Daihachi Chemical Co., Ltd .; MR-200, Nippon Kayaku Co., Ltd .; Kayamar PM-2, Nippon Kayaku Co., Ltd .; Kayamar PM-21,
_{[A-19] [CH 2} = CHCOO (C 2 H 4 O) n] 3 P = O
n = 1; Osaka Organic Co., Ltd .; Biscote 3PA.

  The compound that forms the adsorptive group on the surface of the hydrophilic support may be a polymer. Specific examples thereof include compounds described in JP-A-2005-313491, paragraph number 0049 to paragraph number 0078.

These compounds may be used in a mixture of plural kinds at an arbitrary ratio. This subbing layer is applied to a surface-treated aluminum support with a solution obtained by dissolving the above compound in water or an organic solvent such as methanol, ethanol, methyl ethyl ketone, or a mixed solvent thereof, and dried, or water or methanol, By immersing the surface-treated aluminum support in a solution in which the above compound is dissolved in an organic solvent such as ethanol or methyl ethyl ketone, or a mixed solvent thereof, to adsorb the above compound, and then washing and drying with water or the like. Can be provided. 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 after drying of the undercoat layer is preferably from 0.1-100 mg / m ^2, and more preferably 1 to 30 mg / m ^2.

(Image exposure)
In the lithographic printing plate material of the present invention, an image is formed by irradiating actinic rays according to image data from the surface having the image forming functional layer.

  As the image exposure according to the present invention, scanning exposure using a laser emitting light in the infrared and / or near infrared region, that is, emitting light in a wavelength range of 700 to 1500 nm is more preferably used.

  A gas laser may be used as the laser, but it is particularly preferable to perform scanning exposure using a semiconductor laser that emits light in the near infrared region.

  As an apparatus suitable for scanning exposure that can be used in the present invention, any apparatus can be used as long as it can form an image on the surface of a printing plate material in accordance with an image signal from a computer using a semiconductor laser. There may be.

  In general, (1) a method of exposing the entire surface of the printing plate material by performing two-dimensional scanning using one or a plurality of laser beams on the printing plate material held by the flat plate holding mechanism; ) A printing plate material held along a cylindrical surface inside a fixed cylindrical holding mechanism, and using one or more laser beams from the inside of the cylinder in the circumferential direction of the cylinder (main scanning direction) A method in which the entire surface of the printing plate material is exposed by moving in a direction perpendicular to the circumferential direction (sub-scanning direction) while scanning, and (3) printing held on the surface of a cylindrical drum that rotates about an axis as a rotating body The plate material is printed by moving in the direction perpendicular to the circumferential direction (sub-scanning direction) while scanning in the circumferential direction (main scanning direction) by rotating the drum using one or more laser beams from the outside of the cylinder. A method that exposes the entire plate material That.

  In the present invention, the scanning exposure method (3) is particularly preferable, and the exposure method (3) is used particularly in an apparatus that performs exposure on a printing apparatus.

  The lithographic printing plate material on which an image has been formed in this way can be printed without being subjected to development processing. The lithographic printing plate material after image formation is directly attached to the plate cylinder of the printing press, or the lithographic printing plate material is attached to the plate cylinder of the printing press and then image formation is performed. Alternatively, the non-image portion of the image forming layer can be removed by bringing the ink supply roller into contact with the planographic printing plate material.

  The step of removing the non-image part of the image forming functional layer can be performed by a normal printing sequence using a PS plate, and is preferably a step performed by so-called on-press development processing.

(ink)
The ink that can be used in the lithographic printing method of the present invention may be any ink that can be used for lithographic printing. Specifically, rosin-modified phenolic resin and vegetable oil (linseed oil, tung oil, soybean oil) Etc.), oil-based inks composed of components such as petroleum solvents, pigments, oxidation polymerization catalysts (cobalt, manganese, lead, iron, zinc, etc.), and components such as acrylic oligomers, acrylic monomers, photopolymerization initiators, pigments, etc. And UV curable UV inks, and hybrid inks having both the properties of oil-based inks and the properties of UV inks.

(Dampening water)
As the fountain solution according to the present invention, a general fountain solution used for lithographic printing can be used. The fountain solution used in the present invention preferably contains an alkylene glycol monoalkyl ether compound.

  The alkylene glycol monoalkyl ether compound is a monoether of alkylene glycol and alkyl, and is preferably used by being dissolved in dampening water.

  As the alkylene glycol monoalkyl ether compound, a compound represented by the following general formula (A) is preferably used.

Formula (A)
_{R 11 -O- (CH 2 C (} R 12) HO) n -H
(Wherein R ₁₁ represents an alkyl group having 1 to 6 carbon atoms, R ₁₂ represents a methyl group or a hydrogen atom, and n represents an integer of 1 to 4)
Specific examples of the general formula (A) include ethylene glycol monomethyl ether, diethylene glycol monomethyl ether, triethylene glycol monomethyl ether, tetraethylene glycol monomethyl ether, ethylene glycol monoethyl ether, diethylene glycol monoethyl ether, triethylene glycol monoethyl ether, Tetraethylene glycol monoethyl ether, ethylene glycol monopropyl ether, diethylene glycol monopropyl ether, triethylene glycol monopropyl ether, tetraethylene glycol monopropyl ether, ethylene glycol monoisopropyl ether, diethylene glycol monoisopropyl ether, triethylene glycol Monoisopropyl ether Tetraethylene glycol monoisopropyl ether, ethylene glycol monobutyl ether, diethylene glycol monobutyl ether, triethylene glycol monobutyl ether, tetraethylene glycol monobutyl ether, ethylene glycol monoisobutyl ether, diethylene glycol monoisobutyl ether, triethylene glycol monoisobutyl ether, tetraethylene glycol Monoisobutyl ether, ethylene glycol monotertiary butyl ether, diethylene glycol monotertiary butyl ether, triethylene glycol monotertiary butyl ether, tetraethylene glycol monotertiary butyl ether, propylene glycol monomethyl ether, dipropylene glycol mono Chill ether, tripropylene glycol monomethyl ether, propylene glycol monoethyl ether, dipropylene glycol monoethyl ether, tripropylene glycol monoethyl ether, tetrapropylene glycol monoethyl ether, propylene glycol monopropyl ether, dipropylene glycol monopropyl ether, tripropylene Glycol monopropyl ether, propylene glycol monoisopropyl ether, dipropylene glycol monoisopropyl ether, tripropylene glycol monoisopropyl ether, dipropylene glycol monobutyl ether, tripropylene glycol monobutyl ether, propylene glycol monoisobutyl ether, dipropylene glycol monoiso Examples include butyl ether, tripropylene glycol monoisobutyl ether, propylene glycol monotertiary butyl ether, dipropylene glycol monotertiary butyl ether, and tripropylene glycol monotertiary butyl ether.

  The compounds of the general formula (A) can be used alone or in combination of two or more.

  The content of the compound represented by the general formula (A) in the fountain solution is suitably 0.05 to 5% by mass, preferably 0.2 to 3% by mass, more preferably from the viewpoint of printing durability. Is 0.3-2 mass%.

  In addition to the alkylene glycol monoalkyl ether compound, it is preferable to use a pH adjuster, an auxiliary agent for improving wettability, a water-soluble polymer compound, a chelating agent, an antiseptic, and the like for the fountain solution.

  As the pH adjuster, at least one selected from water-soluble organic acids, inorganic acids, and salts thereof can be used. These compounds are effective in adjusting the pH of the fountain solution or buffering the pH and appropriately etching or preventing corrosion of the lithographic printing plate support. Preferred organic acids include, for example, citric acid, ascorbic acid, malic acid, tartaric acid, lactic acid, acetic acid, gluconic acid, hydroxyacetic acid, succinic acid, malonic acid, levulinic acid, sulfanilic acid, p-toluenesulfonic acid, phosphoric acid, phosphonic acid And phytic acid.

  Examples of inorganic acids include nitric acid and sulfuric acid. Furthermore, alkali metal salts, alkaline earth metal salts or ammonium salts of these organic acids and / or inorganic acids, and organic amine salts are also preferably used.

  One of these organic acids, inorganic acids and salts thereof may be used alone, or a mixture of two or more may be used.

  The addition amount of these pH adjusting agents to the fountain solution is suitably in the range of 0.001% by mass or more and 0.1% by mass or less in combination of the organic acid, inorganic acid and salts thereof. When it is 0.001% by mass or more, the stain at the time of printing is good due to the etching force of aluminum which is the support of the lithographic printing plate. On the other hand, if it is 0.1 mass% or less, it is preferable at the point of the rust of a printing press.

  The pH of the fountain solution is preferably 4.5 or more and 7.5 or less. If the pH is within this range, the occurrence of smudges during printing is small.

  It is preferable to use a surfactant or other solvent as an aid for improving the wettability.

  The surfactant used is preferably an anionic surfactant and / or a nonionic surfactant.

  Examples of anionic surfactants include fatty acid salts, abietates, hydroxyalkanesulfonates, alkanesulfonates, dialkylsulfosuccinates, linear alkylbenzenesulfonates, branched alkylbenzenesulfonates, alkylnaphthalenes Sulfonates, alkylphenoxy polyoxyethylene propyl sulfonates, polyoxyethylene alkyl sulfenyl ether salts, N-methyl-N-oleyl taurine sodium salts, N-alkyl sulfosuccinic acid monoamide disodium salts, petroleum sulfonates, Sulfated castor oil, sulfated beef tallow oil, fatty acid alkyl ester sulfate esters, alkyl sulfate esters, polyoxyethylene alkyl ether sulfate esters, fatty acid monoglyceride sulfate Tell salt, polyoxyethylene alkylphenyl ether sulfate ester salt, polyoxyethylene styryl phenyl ether sulfate ester salt, alkyl phosphate ester salt, polyoxyethylene alkyl ether phosphate ester salt, polyoxyethylene alkylphenyl ether phosphate ester salt, styrene-anhydrous Examples thereof include partial saponification products of maleic acid copolymer, partial saponification products of olefin-maleic anhydride copolymer, and naphthalene sulfonate formalin condensates. Among these, dialkyl sulfosuccinates, alkyl sulfates and alkyl naphthalene sulfonates are particularly preferably used.

  Examples of nonionic surfactants include polyoxyethylene alkyl phenyl ethers, polyoxyethylene polystyryl phenyl ethers, polyoxyethylene polyoxypropylene alkyl ethers, glycerin fatty acid partial esters, sorbitan fatty acid partial esters, penta Erythritol fatty acid partial esters, propylene glycol mono fatty acid esters, sucrose fatty acid partial esters, polyoxyethylene sorbitan fatty acid partial esters, polyoxyethylene sorbitol fatty acid partial esters, polyethylene glycol fatty acid esters, polyglycerin fatty acid partial esters, Polyoxyethylenated castor oil, polyoxyethylene glycerin fatty acid partial esters, fatty acid diethanolamides, N, N-bis-2 Hydroxyalkylamines, polyoxyethylene alkylamines, triethanolamine fatty acid esters, polyoxyethylene - polyoxypropylene block polymers, and the like trialkylamine oxides. In addition, fluorine-based surfactants and silicon-based surfactants can also be used. In the case of using a surfactant, the content thereof is 1% by mass or less, preferably 0.001 to 0.5% by mass in consideration of foaming. Two or more kinds can be used in combination.

  Other auxiliary agents include propylene glycol, dipropylene glycol, tripropylene glycol, tetrapropylene glycol and pentapropylene glycol, ethylene glycol, diethylene glycol, triethylene glycol, butylene glycol, hexylene glycol, 2-ethyl-1,3- Hexanediol, 3-methoxy-3-methyl-1-butanol, 1-butoxy-2-propanol, glycerin, diglycerin, polyglycerin, trimethylolpropane, 1-position substituted with an alkyl group having 1 to 8 carbon atoms 2-pyrrolidone derivatives, 3,5-dimethyl-1-hexyn-3-ol, 2,4,7,9-tetramethyl-5-decyne-4,7-diol, propargyl alcohol (2-propyne-1 -All), 3 Butyn-1-ol, 1-butyne-3-ol, 2-butyne-1,4-diol, such as 3,6-dimethyl-4-octyne-3,6-diol.

  Among these, 3-methoxy-3-methyl-1-butanol and 1-butoxy-2-propanol are particularly preferable.

  These solvents may be used alone or in combination of two or more. In general, these solvents are suitably used in the range of 0.002 to 1% by mass, preferably 0.005 to 0.5% by mass, based on the total mass of the fountain solution.

  Examples of water-soluble polymer compounds include gum arabic, starch derivatives (eg, dextrin, enzymatically degraded dextrin, hydroxypropylated enzymatically degraded dextrin, carboxymethylated starch, phosphate starch, octenyl succinated starch), alginates, and fibrin derivatives. (For example, natural products such as carboxymethyl cellulose, carboxyethyl cellulose, methyl cellulose, hydroxyethyl cellulose) and modified products thereof, polyethylene glycol and copolymers thereof, polyvinyl alcohol and derivatives thereof, polyacrylamide and copolymers thereof, polyacrylic acid and derivatives thereof Copolymer, vinyl methyl ether / maleic anhydride copolymer, vinyl acetate / maleic anhydride copolymer, polystyrene sulfonic acid and its composite, polyvinylpyrrolidone And the like. Among these, carboxymethyl cellulose and hydroxyethyl cellulose are particularly preferable. 0.001-0.5 mass% is suitable with respect to dampening water, and, as for content of a water-soluble polymer compound, More preferably, it is 0.005-0.2 mass%.

  It is preferable to add a chelating agent to the fountain solution. Preferred chelating agents include, for example, ethylenediaminetetraacetic acid, its potassium salt, its sodium salt; diethylenetriaminepentaacetic acid, its potassium salt, sodium salt; triethylenetetraminehexaacetic acid, its potassium salt, its sodium salt, hydroxyethylethylenediaminetriacetic acid Nitrilotriacetic acid, sodium salt; 1-hydroxyethane-1,1-diphosphonic acid, potassium salt, sodium salt; aminotri (methylenephosphonic acid), potassium salt, sodium salt And organic phosphonic acids and phosphonoalkanetricarboxylic acids. Instead of the sodium salt or potassium salt of the chelating agent, an organic amine salt is also effective. These chelating agents are selected so that they are stably present in the dampening water during use and do not impair the printability. As content of the chelate compound in dampening water at the time of use, 0.0001-0.5 mass% is suitable, Preferably it is 0.0005-0.2 mass%.

  Preservatives include phenol or derivatives thereof, formalin, imidazole derivatives, sodium dehydroacetate, 4-isothiazolin-3-one derivatives, benztriazole derivatives, amidine or guanidine derivatives, quaternary ammonium salts, pyridine, quinoline or guanidine derivatives. , Derivatives of diazine or triazole, derivatives of oxazole or oxazine, bromonitroalcohol-based bromonitropropanol, 1,1-dibromo-1-nitro-2-ethanol, 3-bromo-3-nitropentane-2,4-diol Etc. A preferable addition amount is an amount that exerts a stable effect on bacteria, molds, yeasts, etc., and varies depending on the types of bacteria, molds, yeasts, etc. The range of mass% is preferable, and it is preferable to use two or more preservatives that are effective against various molds, bacteria and yeasts.

  The fountain solution according to the present invention may further contain an odor masking agent, a colorant, a rust inhibitor, and an antifoaming agent.

  As the odor masking agent, those represented by the following general formula (M) can be preferably used.

General formula (M)
R ¹ -COOR ²
In the compound of the general formula (M), R ¹ is an alkyl group having 1 to 15 carbon atoms, an alkenyl group, an aralkyl group, or a phenyl group. In the case of an alkyl group or an alkenyl group, the number of carbon atoms is preferably 4-8. When R ¹ represents an alkyl group, an alkenyl group or an aralkyl group, they may be linear or branched. An alkenyl group having one double bond is particularly suitable.

Examples of the aralkyl group include a benzyl group and a phenylethyl group. The alkyl group represented by R ^1, an alkenyl group, one or more hydrogen atoms of the aralkyl group or a phenyl group, may be substituted by a hydroxyl group or an acetyl group. R ² is an alkyl group having 3 to 10 carbon atoms, an aralkyl group, or a phenyl group, which may be linear or branched. In the case of an alkyl group, the number of carbon atoms is preferably 3 to 9. Examples of the aralkyl group include a benzyl group and a phenylethyl group.

  Specific examples of odor masking agents include formic acid, acetic acid, propionic acid, butyric acid, isobutyric acid, 2-ethylbutyric acid, valeric acid, isovaleric acid, 2-methylvaleric acid, hexanoic acid (caproic acid), 4-methylpentanoic acid (Isohexanoic acid), 2-hexenoic acid, 4-pentenoic acid, heptanoic acid, 2-methylheptanoic acid, octanoic acid (caprylic acid), nonanoic acid, decanoic acid (capric acid), 2-decenoic acid, lauric acid or myristic Examples include esters of acids.

  In addition, there are acetoacetate esters such as benzyl phenylacetate, ethyl acetoacetate and 2-hexyl acetoacetate. Among them, preferred are n-pentyl acetate, isopentyl acetate, n-butyl butyrate, n-pentyl butyrate and isopentyl butyrate, and n-butyl butyrate, n-pentyl butyrate and isopentyl butyrate are particularly preferable.

  The content of these odor masking agents in the fountain solution is suitably 0.001 to 0.5% by mass, more preferably 0.002 to 0.2% by mass, based on the total mass of the fountain solution. . By using these, the work environment can be further improved. Also. Vanillin, ethyl vanillin or the like may be used in combination.

  As the colorant, food colorants and the like can be preferably used. For example, CINo. 19140, 15985 and CI No. 16185, 45430, 16255, 45380, 45100, and purple pigments such as CI No. 42640, as a blue pigment, CI No. 42090 and 73015, CINo. 42095, and the like. As content of the coloring agent in the dampening water in the case of using, 0.0001-0.5 mass% is preferable.

  Examples of the rust preventive include benzotriazole, 5-methylbenzotriazole, thiosalicylic acid, benzimidazole and derivatives thereof. When used, the content of the rust inhibitor in the fountain solution is preferably 0.0001 to 0.5% by mass.

  As the antifoaming agent, a silicon antifoaming agent is preferable, and any of emulsifying dispersion type and solubilizing type can be used.

(Printer)
In the lithographic printing method of the present invention, a known lithographic printing machine having a plate cylinder on which a printing plate material is mounted, a member for supplying dampening water onto the printing plate surface, and a member for supplying ink can be used.

Example 1
<Preparation of grain-shaped aluminum support>
An aluminum plate (material 1050, tempered: H16) having a thickness of 0.24 mm was immersed in a 5% aqueous sodium hydroxide solution maintained at 65 ° C., degreased for 1 minute, and then washed with water.

Next, in an aqueous 1% hydrochloric acid solution maintained at 25 ° C., electrolytic polishing was performed with a carbon electrode at 40 ° C., a current of 20 amperes, and 20 seconds (400 A · sec / dm ² ), and grained. After washing with water, subsequently, an immersion treatment (desmut treatment) was performed at 60 ° C. for 60 seconds with a 2% by weight aqueous caustic soda solution.

  Subsequently, anodization was performed under the following conditions.

Treatment bath is 30% by mass of sulfuric acid aqueous solution
Current density 2A / dm ²・ Processing temperature is 40 ℃
The treatment time is 60 seconds, followed by immersion for 30 seconds in hot water at 80 ° C. It was dried with 40 ° C. warm air to obtain a grained aluminum support. The produced hydrophilic substrate was measured with a surface roughness meter (RSTPLUS manufactured by WYKO), and Ra was 0.34 μm.

<Preparation of planographic printing plate material 1>
An undercoat layer coating solution (1) having the following composition was applied to the obtained aluminum support having a grain shape using a bar having a liquid volume of 7.5 ml / m ^2, and then at 80 ° C. for 10 seconds. Oven dried.

(Undercoat layer coating solution (1))
15g of water
Methanol 135g
Illustrative compound [A-21] 0.8 g
Next, an image-forming functional layer coating solution (1) having the following composition was bar-coated and then oven-dried at 100 ° C. for 60 seconds to form an image-forming functional layer, whereby a lithographic printing plate material 1 was obtained.

(Image forming functional layer coating solution (1))
Infrared absorbing dye (structure shown in Table 1 below) 0.05 g
Polymerization initiator (Exemplary Compound QF-4) 0.2 g
The following binder polymer (1) (average molecular weight 80,000) 0.5 g
Polymerizable compound (isocyanuric acid EO-modified triacrylate) (manufactured by Shin-Nakamura Chemical Co., Ltd., NK ester M-315) 1.0 g
Hydrophobic precursor: Thermoplastic fine particle microcrystalline wax emulsion A206 (manufactured by Gifu Shellac Co., Ltd., average particle size 0.5 μm, softening point 65 ° C., melting point 108 ° C., melt viscosity 8 ° cps at 140 ° C., solid content 40%) 8g
Victoria Pure Blue Naphthalenesulfonate 0.02g
0.1 g of the following fluorosurfactant (1)
Methyl ethyl ketone 18.0g

<Preparation of planographic printing plate material 2>
An undercoat layer coating solution (2) having the following composition was coated on the support prepared in Example 1 using a bar having a liquid volume of 7.5 ml / m ² and then oven-dried at 80 ° C. for 10 seconds. did.

(Undercoat layer coating solution (2))
15g of water
Methanol 135g
Illustrative compound [A-27] 0.8 g
Next, an image-forming functional layer coating solution (2) having the following composition was bar-coated on the support on which the undercoat layer was applied, and then oven-dried at 70 ° C. for 60 seconds to form an image-forming functional layer. The image forming functional layer coating solution (2) was obtained by mixing and stirring the A component and the B component immediately before coating.

(Image forming functional layer coating solution (2))
<A component>
50g propylene glycol monomethyl ether
Methyl ethyl ketone 10g
Polymeric compound (triacrylate of ethylene oxide 3-mole adduct of isocyanuric acid (Aronix M-315 manufactured by Toagosei Co., Ltd.)) 1.2 g
0.5 g of the following binder polymer (2) having an average molecular weight of 80,000
Hydrophobic precursor: Thermoplastic fine particle microcrystalline wax emulsion A206 (manufactured by Gifu Shellac Co., Ltd., average particle size 0.5 μm, softening point 65 ° C., melting point 108 ° C., melt viscosity 8 ° cps at 140 ° C., solid content 40%) 8g
0.1 g of the fluorosurfactant (1)
<B component>
Microcapsule dispersion (prepared as follows) (in terms of solid content) 5 g
Preparation of microcapsule dispersion As oil phase components, trimethylolpropane and xylene diisocyanate adduct (Mitsui Takeda Chemicals, Takenate D-110N) 10 g, pentaerythritol triacrylate (Nippon Kayaku Co., Ltd., SR444) 3.15 g, infrared absorbing dye (structure shown in Table 1 below) 0.35 g, 3- (N, N-diethylamino) -6-methyl-7-anilinofluorane (ODB manufactured by Yamamoto Kasei), polymerization An initiator (Exemplary Compound QS-16) 0.6 g and Piionin A-41C (manufactured by Takemoto Yushi Co., Ltd.) 0.1 g were dissolved in ethyl acetate 18 g.

  As an aqueous phase component, 40 g of a 4% by mass aqueous solution of polyvinyl alcohol PVA-205 was prepared. The oil phase component and the aqueous phase component were mixed and emulsified for 10 minutes at 12000 rpm using a homogenizer. The obtained emulsion was added to 25 g of distilled water, stirred at room temperature for 30 minutes, and then stirred at 40 ° C. for 3 hours. The microcapsule solution thus obtained was diluted with distilled water so that the solid content concentration was 15% by mass. The average particle size was 0.25 μm.

  2.640 g of microcapsule liquid and 2.425 g of water were mixed to prepare a microcapsule dispersion.

Further, a protective layer coating solution 1 having the following composition was bar coated thereon, followed by oven drying at 65 ° C. for 30 seconds to form a protective layer having a dry coating amount of 0.3 g / m ² and then aging at 40 ° C. for 24 hours. The lithographic printing plate material 2 was obtained by processing.

(Protective layer coating solution (1))
Sodium polyacrylate aqueous solution 15 parts by mass (trade name: Aqualic DL522, Nippon Shokubai Co., Ltd., average molecular weight 170,000 solids 30.5%: water-soluble resin) Block isocyanate WB-700 40 parts by mass Disaccharide trehalose powder ( Hayashibara Shoji brand name Treha, melting point 97 ° C),
Solid content 10% by weight 35 parts by weight Blue pigment (trade name: Blue No. 2, manufactured by Kiriya Chemical Co., Ltd.) 2 parts by weight Matting agent: Monodispersed silica particles having an average particle size of 8 μm 3 parts by weight Matting agent: Average particle size 3. 5 μm monodispersed silica particles of 5 μm <Preparation of printed matter>
A semiconductor laser light source (emission wavelength: 830 nm, spot size: 10 μm, resolution: 2000 dpi in both the scanning direction and the sub-scanning direction (dpi represents the number of dots per 2.54 cm)) is used for the produced lithographic printing plate material. Based on the data, the amount of energy that can be placed on the plate surface was 150 mJ / cm ² and image exposure was performed. The exposed image includes a solid image and a 1 to 99% halftone dot image.

  The exposed lithographic printing plate material is fixed to a cylinder of a DAIYA1F-1 printing machine manufactured by Mitsubishi Heavy Industries, Ltd., and a dampening solution 1 is applied on the plate surface by turning on a swim roller while the cylinder is rotated. Is supplied for 2 rotations of the cylinder, and then the ink application roller is turned on while the water application roller is turned ON, and the cylinder 2 supplies Fusion G ST Crimson N (soybean oil ink) manufactured by Dainippon Ink Chemical Co., Ltd. The paper was fed while rotating, and then the paper feeding was started with the watering roller and the ink form roller turned on, and printing was started.

Dampening water 1
Propylene glycol mono-n-butyl ether 1.0kg
1,2-propanediol 0.5kg
3,6-dimethyl-4-octyne-3,6-diol 0.5 kg
Perfluorooctane sulfonic acid 0.1kg
Ethylenediaminetetramethylenephosphonic acid 0.8kg
Ethylenoside propylene oxide copolymer 0.1kg
Glycerin 0.1kg
Ammonium nitrate 0.02kg
Carboxymethylcellulose 0.01kg
Primary ammonium phosphate 0.4kg
0.01kg of diammonium citrate
Sodium acetate 0.01kg
2,3-Bromo-2-nitroethanol 0.002kg
2-Methyl-5-chloro-4-isothiazolin-3-one 0.002 kg
Diluted with pure water to 10 liters.

<Evaluation method of printed matter>
<Evaluation of dirt recovery property>
1000 sheets of the exposed printing plate sample were printed on coated paper. Thereafter, normal printing (nip of both the ink roller and the water roller) was performed with only the ink roller nipped and the ink adhered to the entire surface. At that time, the number of non-imaged areas in the printed material where the stains disappeared was measured and used as an index for stain recovery. A smaller number is better.

<< Evaluation of halftone dot quality (image quality of printed matter) >>
After printing 5000 sheets on coated paper, the image quality of the printed matter is ranked by visually observing the quality of the 2% halftone image with a 100 × magnifier, and the halftone quality is evaluated, and this rank is used as an index of halftone dot reproducibility. . Rank 5 is a high-quality halftone dot with no fringes, and the rank was lowered as quality deteriorated. Below rank 3, the image quality is unusable.

<Prevention of dirt>
After printing 5,000 sheets of coated paper, the printed matter was visually observed to confirm the presence or absence of background stains in the non-image area. Rank 5 is a state in which no dirt is observed, and the rank is lowered as the dirt is seen. Below rank 3, there is dirt that cannot be used.

  The results are shown in Table 1. It can be seen from Table 1 that the lithographic printing plate material of the present invention has excellent stain recovery and anti-stain properties, excellent printability, and excellent dot reproducibility.

Claims (4)

A printing plate material that can be developed on a printing press having an image forming functional layer on an aluminum support, the image forming functional layer containing a photopolymerizable compound and a polymerization initiator, and the image forming of the aluminum support. A lithographic printing plate material comprising a layer containing a compound represented by the following general formula (1), (2), (3) or (4) on the side having a functional layer.

[Wherein, A ₁ and B ₁ represent a substituent. ]

Wherein, A ₂ and B ₂ represents a substituent. ]

[Wherein R ₁ and R ₂ represent a hydrogen atom or an alkyl group. A ₃ and B ₃ can completely overlap with the original group when rotated 180 ° around the axis connecting the bond point with the carbon atom indicated by C in the general formula and the line connecting the carbon atom. Represents a group. However, the sum of the hydroxyl groups of A ₃ and B ₃ is 0 or more and 1 or less. ]

[Wherein R ₃ and R ₄ represent a hydrogen atom or an alkyl group. A ₄ and B ₄ can completely overlap with the original group when rotated about 180 ° around the axis connecting the bond point with the carbon atom indicated by C in the general formula and the line connecting the carbon atom. Represents a group. However, the sum of the hydroxyl groups A ₄ and B ₄ have is 0 or more and 1 or less. ] The lithographic printing plate material according to claim 1, wherein the image-forming functional layer contains heat-fusible particles or heat-fusible particles. The lithographic printing plate material according to claim 1 or 2, wherein the aluminum support has a hydrophilic surface. After the lithographic printing plate material according to any one of claims 1 to 3 is image-exposed, the lithographic printing plate material is mounted on a printing machine, and a dampening solution and ink are supplied to the surface of the lithographic printing plate material to form a non-image portion. A lithographic printing method comprising removing and printing.