JP2005186504A - Lithographic printing plate original plate and lithographic printing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a lithographic printing plate original plate having excellent on-machine developing properties, thin line reproducibility, good capability of suppressing staining and printing resistance, and a lithographic printing method using the same. <P>SOLUTION: The lithographic printing plate original plate has an image recording layer on a hydrophilic support wherein the peak area of fluorine, silicon and aluminum measured by an X-ray photoelectron spectroscopic method is at a specific ratio, and contains a copolymer having at least (a1) a repeating unit contains at least one ethylenically unsaturated bond, and (a2) a repeating unit containing at least one functional group interacting with the support surface, in the image recording layer or the other layers. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a lithographic printing plate precursor and a lithographic printing method using the same. Specifically, a lithographic printing plate precursor capable of direct plate making by scanning with an infrared laser based on a digital signal from a computer or the like, and developing the lithographic printing plate precursor on a printing press, the so-called lithographic printing plate precursor. The present invention relates to a planographic printing method for printing.

In general, a lithographic printing plate comprises an oleophilic image area that receives ink in the printing process and a hydrophilic non-image area that receives dampening water. Lithographic printing utilizes the property that water and oil-based inks repel each other, so that the oleophilic image area of the lithographic printing plate is the ink receiving area, and the hydrophilic non-image area is dampened with the water receiving area (ink non-receiving area). In this method, a difference in ink adhesion is caused on the surface of the lithographic printing plate, and after ink is applied only to the image area, the ink is transferred to a printing medium such as paper and printed.
In order to produce this lithographic printing plate, conventionally, a lithographic printing plate precursor (PS plate) in which an oleophilic photosensitive resin layer (image recording layer) is provided on a hydrophilic support has been widely used. Normally, after exposing a lithographic printing plate precursor through an original image such as a lithographic film, the image recording layer in the image area is left, and the image recording layer in the non-image area is dissolved with an alkaline developer or an organic solvent. The lithographic printing plate is obtained by carrying out plate making by a method of exposing the surface of the hydrophilic support by removing it.

  In the conventional plate-making process of a lithographic printing plate precursor, a step of dissolving and removing the non-image area with a developing solution or the like corresponding to the image recording layer is necessary after exposure. One of the problems is to make the system unnecessary or simplified. In particular, in recent years, disposal of waste liquids discharged with wet processing has become a major concern for the entire industry due to consideration for the global environment, and therefore, the demand for solving the above-mentioned problems has become stronger.

On the other hand, as one of simple plate making methods, an image recording layer that can remove a non-image portion of a lithographic printing plate precursor in a normal printing process is used. A method called on-press development has been proposed in which a part is removed to obtain a lithographic printing plate.
As a specific method of on-press development, for example, a method of using a lithographic printing plate precursor having an image recording layer that can be dissolved or dispersed in an fountain solution, an ink solvent, or an emulsion of a fountain solution and an ink. , A method of mechanically removing the image recording layer by contact with rollers or a blanket cylinder of a printing press, cohesion force of the image recording layer by penetration of dampening water, ink solvent, etc., or between the image recording layer and the support. There is a method in which after the adhesive force is weakened, the image recording layer is mechanically removed by contact with rollers or a blanket cylinder.
In the present invention, unless otherwise specified, the “development process step” refers to using a device other than a printing press (usually an automatic developing machine) and bringing a liquid (usually an alkaline developer) into contact therewith. Refers to the process of removing the unexposed portion of the image recording layer of the lithographic printing plate precursor and exposing the surface of the hydrophilic support, and “on-press development” refers to a liquid (usually printing ink) using a printing press. And / or a dampening solution) to remove the unexposed portion of the image recording layer of the lithographic printing plate precursor and expose the surface of the hydrophilic support.

On the other hand, in recent years, digitization techniques for electronically processing, storing, and outputting image information by a computer have become widespread, and various new image output methods corresponding to such digitization techniques are put into practical use. It is becoming. Along with this, digitized image information is carried by high-convergence radiation such as laser light, and the lithographic printing plate precursor is scanned and exposed with that light, directly without using a lithographic film. Computer-to-plate technology for manufacturing is attracting attention. Accordingly, obtaining a lithographic printing plate precursor adapted to such a technique is one of the important technical issues.

As described above, in recent years, simplification, drying, and no processing of plate making operations have become more desirable than ever in terms of both consideration for the global environment and adaptation to digitalization. It is coming.
However, when the conventional image recording method using light in the ultraviolet to visible region is used for simplification of plate making operations such as on-press development, the image recording layer is not fixed even after exposure, so that it has sensitivity to room light. After the lithographic printing plate precursor was taken out of the package, it was necessary to keep it completely shielded from light until the on-press development was completed.

Recently, high-power lasers such as semiconductor lasers that emit infrared rays having a wavelength of 760 to 1200 nm, YAG lasers, etc. have become available at a low cost. Therefore, a method using these high-power lasers as an image recording light source has been considered promising.
In the conventional plate making method using light in the ultraviolet to visible region, a photosensitive lithographic printing plate precursor is subjected to imagewise exposure from low to medium illuminance, and image-like physical property changes due to photochemical reaction in the image recording layer. Record an image. On the other hand, in the method using the above-described high-power laser, a large amount of light energy is irradiated to the exposure region in a very short time, and the light energy is efficiently converted into heat energy. In the process, a thermal change such as a chemical change, a phase change, a form or a structure is caused and the change is used for image recording. Therefore, image information is input by light energy such as laser light, but image recording is performed in a state in which reaction by heat energy is taken into account in addition to light energy. Usually, such a recording method using heat generated by high power density exposure is called heat mode recording, and changing light energy to heat energy is called photothermal conversion.

  The major advantages of the plate making method using heat mode recording are that the image recording layer is not exposed to light at a normal illuminance level such as indoor lighting, and that fixing of images recorded by high illuminance exposure is not essential. is there. That is, the lithographic printing plate precursor used for heat mode recording is not likely to be exposed to room light before exposure, and image fixing is not essential after exposure. Therefore, for example, if an image recording layer that is insolubilized or solubilized by exposure using a high-power laser is used, and the plate making process in which the exposed image recording layer is imaged to form a lithographic printing plate is performed by on-machine development, exposure is performed. Later, it is expected that a printing system in which an image is not affected even if exposed to ambient light in a room will be possible, and its realization is desired.

  As such a lithographic printing plate precursor, for example, a lithographic printing plate precursor in which an image forming layer in which hydrophobic thermoplastic polymer particles are dispersed in a hydrophilic binder is provided on a hydrophilic support is known ( For example, see Patent Document 1.) This lithographic printing plate precursor is exposed to an infrared laser, and the hydrophobic thermoplastic polymer particles are fused and coalesced by heat to form an image. Then, the lithographic printing plate precursor is attached onto a cylinder of a printing machine, dampening water and / or On-press development is possible by supplying ink.

  However, the method for forming an image by merging the polymer fine particles by simple thermal fusion as described above exhibits good on-press developability, but the image strength is extremely weak and the printing durability is insufficient.

  In order to improve the printing durability of such an on-press developable lithographic printing plate precursor, a thermosensitive layer comprising a microcapsule containing a compound having a functional group that reacts with heat on a hydrophilic support is provided. There is proposed a lithographic printing plate precursor comprising an infrared absorber contained in a heat-sensitive layer or an adjacent layer (see Patent Document 2 and Patent Document 3).

As another technique for improving printing durability, a lithographic printing plate precursor capable of on-press development, which is provided with a photosensitive layer containing an infrared absorber, a radical polymerization initiator and a polymerizable compound on a support, is known. (See Patent Document 4).
The method using a reaction such as a polymerization reaction as described above can improve the image strength because the chemical bond density of the image portion is higher than that of the image portion formed by thermal fusion of polymer fine particles. However, it is still insufficient in terms of both on-press developability, fine line reproducibility and printing durability.
On the other hand, regarding a lithographic printing plate support, Patent Document 5 discloses that the contents of the inorganic fluorine compound and the silicate compound on the surface of the support are in a specific relational expression.
Japanese Patent No. 2938397 JP 2001-277740 A JP 2001-277742 A JP 2002-287334 A Japanese Patent Laid-Open No. 2003-1961

  The present invention has been made in view of the above prior art, and provides a lithographic printing plate precursor excellent in on-press developability, fine line reproducibility, stain resistance and printing durability, and a lithographic printing method using the same. The purpose is to do.

  As a result of intensive studies to achieve the above object, the inventor contains a copolymer containing a specific group in the image recording layer or other layer of the lithographic printing plate precursor, and the surface state of the support. By specifying the above, the inventors have found that the above object can be achieved, and have completed the present invention.

That is, the present invention is as follows.
(1) The surface has an image recording layer on a hydrophilic support satisfying the following formula (1), and the image recording layer or other layer contains at least one (a1) ethylenically unsaturated bond. A lithographic printing plate precursor comprising a copolymer having a repeating unit and (a2) a repeating unit containing at least one functional group that interacts with the support surface.
0.30 ≦ (A + B) / (A + B + C) ≦ 0.90 (1)
A: Peak area of fluorine (1S) obtained by measurement using X-ray photoelectron spectroscopy (counts · eV / sec)
B: Peak area of silicon (2P) obtained by measurement using X-ray photoelectron spectroscopy (counts · eV / sec)
C: Peak area of aluminum (2P) obtained by measurement using X-ray photoelectron spectroscopy (counts · eV / sec)

(2) The lithographic printing plate precursor as described in (1) above, wherein the copolymer is a copolymer having a hydrophilic portion.
(3) The lithographic printing plate precursor as described in (1) or (2) above, wherein the copolymer is contained in an undercoat layer provided between the hydrophilic support and the image recording layer.

(4) The surface has an image recording layer on a hydrophilic support satisfying the following formula (1), and the image recording layer or other layer contains at least one (a1) ethylenically unsaturated bond. A lithographic printing plate precursor comprising a copolymer having a repeating unit and (a2) a repeating unit containing at least one functional group that interacts with the support surface is mounted on a printing press and imagewise exposed with an infrared laser. Or after imagewise exposure with an infrared laser, it is mounted on a printing press, and the lithographic printing plate precursor is supplied with printing ink and fountain solution to remove the infrared unexposed portion of the image recording layer. Lithographic printing method to remove and print.
0.30 ≦ (A + B) / (A + B + C) ≦ 0.90 (1)
A: Peak area of fluorine (1S) obtained by measurement using X-ray photoelectron spectroscopy (counts · eV / sec)
B: Peak area of silicon (2P) obtained by measurement using X-ray photoelectron spectroscopy (counts · eV / sec)
C: Peak area of aluminum (2P) obtained by measurement using X-ray photoelectron spectroscopy (counts · eV / sec)

(5) The lithographic printing method according to (4), wherein the copolymer is a copolymer having a hydrophilic portion.
(6) The lithographic printing method according to (4) or (5), wherein the copolymer is contained in an undercoat layer provided between the hydrophilic support and the image recording layer.

  According to the present invention, it is possible to provide a lithographic printing plate precursor excellent in on-press developability, fine line reproducibility, stain resistance and printing durability, and a lithographic printing method using the same.

Hereinafter, the present invention will be described in detail.
The lithographic printing plate precursor according to the present invention contains, for example, (A) an infrared absorber, (B) a polymerization initiator, (C) a polymerizable compound, and (D) a binder polymer. It has an image-recording layer that can be removed by both, and the image-recording layer or other layer further interacts with (a2) at least one repeating unit containing at least one ethylenically unsaturated bond and (a2) the support surface. One feature is that it includes a copolymer having a repeating unit containing at least one functional group (hereinafter also referred to as “specific copolymer”). Moreover, it is preferable that the said specific copolymer has a hydrophilic part.

  As the specific copolymer, those containing a repeating unit represented by the following formula (I) are preferable.

In formula (I), A ₁ represents a repeating unit containing at least one ethylenically unsaturated bond, and A ₂ represents a repeating unit containing at least one functional group that interacts with the support surface. x and y represent copolymerization ratios.
In the formula (I), the repeating unit represented by A ₁ is preferably represented by the following formula (A1).

In the formula, R _{1 to} R ₃ each independently represent a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, or a halogen atom. R _{4 to} R ₆ each independently represents a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, a halogen atom, an acyl group, or an acyloxy group. Further, R ₄ and R ₅ , or R ₅ and R ₆ may form a ring. L represents a divalent linking group selected from the group consisting of -CO-, -O-, -NH-, a divalent aliphatic group, a divalent aromatic group, and combinations thereof.

Specific examples of L composed of combinations are given below. In the following examples, the left side is bonded to the main chain, and the right side is bonded to the ethylenically unsaturated bond.
L1: -CO-NH-divalent aliphatic group -O-CO-
L2: —CO—divalent aliphatic group —O—CO—
L3: -CO-O-divalent aliphatic group -O-CO-
L4: -Divalent aliphatic group -O-CO-
L5: -CO-NH-divalent aromatic group -O-CO-
L6: -CO-divalent aromatic group -O-CO-
L7: -Divalent aromatic group -O-CO-
L8: -CO-divalent aliphatic group-CO-O-divalent aliphatic group-O-CO-
L9: -CO-divalent aliphatic group-O-CO-divalent aliphatic group-O-CO-
L10: -CO-Divalent aromatic group -CO-O-Divalent aliphatic group -O-CO-
L11: -CO-Divalent aromatic group -O-CO-Divalent aliphatic group -O-CO-
L12: -CO-divalent aliphatic group-CO-O-divalent aromatic group-O-CO-
L13: -CO-Divalent aliphatic group -O-CO-Divalent aromatic group -O-CO-
L14: -CO-divalent aromatic group-CO-O-divalent aromatic group-O-CO-
L15: -CO-Divalent aromatic group -O-CO-Divalent aromatic group -O-CO-

The divalent aliphatic group means an alkylene group, a substituted alkylene group, an alkenylene group, a substituted alkenylene group, an alkynylene group, a substituted alkynylene group or a polyalkyleneoxy group. Of these, an alkylene group, a substituted alkylene group, an alkenylene group, and a substituted alkenylene group are preferable, and an alkylene group and a substituted alkylene group are more preferable.
The divalent aliphatic group is preferably a chain structure rather than a cyclic structure, and more preferably a linear structure than a branched chain structure.
The number of carbon atoms in the divalent aliphatic group is preferably 1 to 20, more preferably 1 to 15, further preferably 1 to 12, and further preferably 1 to 10. It is preferably 1 to 8, and most preferably.
Examples of the substituent of the divalent aliphatic group include a halogen atom (F, Cl, Br, I), a hydroxyl group, a carboxyl group, an amino group, a cyano group, an aryl group, an alkoxy group, an aryloxy group, and an acyl group. , Alkoxycarbonyl group, aryloxycarbonyl group, acyloxy group, monoalkylamino group, dialkylamino group, arylamino group and diarylamino group.

The divalent aromatic group means an aryl group or a substituted aryl group. Preferable are phenylene, substituted phenylene group, naphthylene and substituted naphthylene group.
Examples of the substituent for the divalent aromatic group include an alkyl group in addition to the examples of the substituent for the divalent aliphatic group.

In the formula (I), the repeating unit represented by A ₂ is specifically represented by the following formula (A2).

In formula, R < ₁ > -R < ₃ > and L are synonymous with what is represented by said Formula (A1). Q represents a functional group that interacts with the support surface (hereinafter sometimes abbreviated as “specific functional group”).
Specific functional groups include, specifically, Si—OH, Si—O ⁻ , Al ³⁺ , aluminum oxide, zirconium oxide, etc. on the support surface, covalent bond, ionic bond, hydrogen bond, polar interaction, van der Waals Examples include groups capable of interaction such as interaction. Specific examples of the specific functional group are listed below.

(In the above formula, R _{11 to} R ₁₃ each independently represents a hydrogen atom, an alkyl group, an aryl group, an alkynyl group, or an alkenyl group, and M ₁ and M ₂ each independently represent a hydrogen atom, a metal atom, or Represents an ammonium group, and X ⁻ represents a counter anion.)
Among these, the specific functional group is preferably an onium base such as an ammonium group or a pyridinium group, a β-diketone group such as a phosphate group, a phosphonic acid group, a boric acid group, or an acetylacetone group.

In the formula (A2), L represents a divalent linking group selected from the group consisting of —CO—, —O—, —NH—, a divalent aliphatic group, a divalent aromatic group, and combinations thereof. .
Specific examples of L composed of combinations include the following in addition to the specific examples of L in (A1). In the following examples, the left side is bonded to the main chain, and the right side is bonded to the ethylenically unsaturated bond.
L16: —CO—NH—
L17: -CO-O-
L18: -Divalent aromatic group-

  The repeating unit represented by the formula (A2) may have a hydrophilic portion. When the hydrophilic part is not contained in the formula (A2), the copolymer used in the present invention preferably further contains a repeating unit represented by the following formula (A3) as a copolymerization component.

In formula, R < ₁ > -R < ₃ > and L are synonymous with what is represented by said Formula (A1). W represents the following group.

However, M ₁ is the same meanings as those represented in the description of the formula (A2).
R ₇ and R ₈ each independently represents a hydrogen atom or a linear or branched alkyl group having 1 to 6 carbon atoms. Here, R ₇ and R ₈ may form a nitrogen-containing ring structure.
R ₉ represents a linear or branched alkylene group having 1 to 6 carbon atoms.
R ₁₀ represents a hydrogen atom or an alkyl group having 1 to 12 carbon atoms.
n represents an integer of 1 to 100.
As a molecular weight of the said specific copolymer, the range of 500-100,000 is preferable at a mass mean molecular weight, and the range of 700-50,000 is more preferable. Further, (a1) is preferably from 5 to 80 mol%, more preferably from 10 to 50 mol%, based on all copolymerized monomers. (A2) is preferably from 5 to 80 mol%, more preferably from 10 to 50 mol%, based on all copolymerized monomers. Furthermore, (a3) is preferably from 5 to 80 mol%, more preferably from 10 to 50 mol%, based on all copolymerized monomers.

  Specific examples of the specific copolymer used in the present invention are shown below, but are not limited thereto.

In the present invention, the specific copolymer may be used in the image recording layer such as an undercoat layer (intermediate layer) described below provided between the support and the image recording layer. Although it can be contained in a layer adjacent to the image recording layer, it is particularly preferable to use it in the undercoat layer since the effect of the present invention is sufficiently exhibited. Since the undercoat layer functions as a heat insulating layer, heat generated by exposure with an infrared laser is not diffused to the support and can be used efficiently, so that there is an advantage that high sensitivity can be achieved. In addition, in the unexposed area, the image recording layer is easily peeled off from the support, so that the on-press developability is improved.
In the present invention, when the specific copolymer is used for the undercoat layer, the copolymer is usually diluted with a solvent. Examples of the solvent include water and organic solvents such as methanol, ethanol, propanol, isopropanol, ethylene glycol, hexylene glycol, THF, DMF, 1-methoxy-2-propanol, dimethylacetamide, dimethyl sulfoxide, and particularly alcohols. Is preferred. These organic solvents can also be mixed and used.
When the specific copolymer compound is used for the undercoat layer, the specific copolymer alone may be coated on the hydrophilic support, or may be used in combination with an undercoat agent such as an organic compound described later if necessary.

  As a density | concentration (concentration of a specific copolymer) of undercoat layer coating liquid, 0.001-10 mass% is preferable, More preferably, it is 0.01-5 mass%, More preferably, it is 0.05-1 mass. %. A surfactant described later may be added to the undercoat layer as necessary.

The coating amount in the case where the specific copolymer contained in the undercoat layer (solids) is preferably from 1 to 30 mg / m ^2, and more preferably 3 to 30 mg / m ^2.

Next, the image recording layer in the planographic printing plate precursor according to the invention will be described in detail.
The planographic printing plate precursor of the present invention contains, for example, (A) an infrared absorber, (B) a polymerization initiator, (C) a polymerizable compound, and (D) a binder polymer on a support, Those having an image recording layer removable with water or both of them are preferred.
Hereinafter, each component constituting the image recording layer in this preferred embodiment will be described in detail.

[(A) Infrared absorber]
The image recording layer in the present invention preferably contains an infrared absorbing agent in order to efficiently perform image formation using a laser emitting infrared light of 760 to 1200 nm as a light source. The infrared absorber has a function of converting absorbed infrared rays into heat. Due to the heat generated at this time, a polymerization initiator (radical generator) described later is thermally decomposed to generate radicals. Such an infrared absorber used in the present invention is a dye or pigment having an absorption maximum at a wavelength of 760 to 1200 nm.

As the dye, commercially available dyes and known dyes described in documents such as “Dye Handbook” (edited by the Society for Synthetic Organic Chemistry, published in 1970) can be used. Specifically, dyes such as azo dyes, metal complex azo dyes, pyrazolone azo dyes, naphthoquinone dyes, anthraquinone dyes, phthalocyanine dyes, carbonium dyes, quinoneimine dyes, methine dyes, cyanine dyes, squarylium dyes, pyrylium salts, metal thiolate complexes, etc. Is mentioned.
Preferred dyes include, for example, cyanine dyes described in JP-A-58-125246, JP-A-59-84356, JP-A-60-78787, JP-A-58-173696, The methine dyes described in JP-A-58-181690 and JP-A-58-194595, JP-A-58-112793, JP-A-58-224793, JP-A-59-48187, Naphthoquinone dyes described in JP-A-59-73996, JP-A-60-52940, JP-A-60-63744, and the like, squarylium dyes described in JP-A-58-112792, and the like; And cyanine dyes described in British Patent No. 434,875.

  In addition, a near infrared absorption sensitizer described in US Pat. No. 5,156,938 is also preferably used, and a substituted arylbenzo (thio) described in US Pat. No. 3,881,924 is also suitable. ) Pyrylium salt, trimethine thiapyrylium salt described in JP-A-57-142645 (US Pat. No. 4,327,169), JP-A-58-181051, 58-220143, 59- No. 41363, 59-84248, 59-84249, 59-146063, 59-146061, and pyrine compounds described in JP-A-59-216146. In US Pat. No. 4,283,475, the pentamethine thiopyrylium salt, etc., and Japanese Patent Publication Nos. 5-13514 and 5-19702 are disclosed. Pyrylium compounds are also preferably used. Another example of a preferable dye is a near-infrared absorbing dye described in US Pat. No. 4,756,993 as formulas (I) and (II).

Among these dyes, cyanine dyes, squarylium dyes, pyrylium salts, nickel thiolate complexes, and indolenine cyanine dyes are particularly preferable. Further, cyanine dyes and indolenine cyanine dyes are preferred, and one particularly preferred example is a cyanine dye represented by the following general formula (i).

In formula (i), X ¹ represents a hydrogen atom, a halogen atom, -NPh _2, X ² -L ¹ or a group shown below.

X ² in the general formula (i) represents an oxygen atom, a nitrogen atom, or a sulfur atom, and L ¹ is a hydrocarbon group having 1 to 12 carbon atoms, an aromatic ring having a hetero atom, or carbon containing a hetero atom. A hydrocarbon group having 1 to 12 atoms is shown. Here, the hetero atom represents N, S, O, a halogen atom, or Se. Xa ^- the Za described later ^- is defined as for, R ^a represents a hydrogen atom, an alkyl group, an aryl group, a substituted or unsubstituted amino group, substituted or unsubstituted amino group and a halogen atom. Ph represents a phenyl group.

R ¹ and R ² in the general formula (i) each independently represent a hydrocarbon group having 1 to 12 carbon atoms. From the storage stability of the recording layer coating solution, R ¹ and R ² are preferably hydrocarbon groups having 2 or more carbon atoms, and R ¹ and R ² are bonded to each other to form a 5-membered ring or It is particularly preferable that a 6-membered ring is formed.

Ar ¹ and Ar ² may be the same or different and each represents an aromatic hydrocarbon group which may have a substituent. Preferred aromatic hydrocarbon groups include a benzene ring and a naphthalene ring. Moreover, as a preferable substituent, a C12 or less hydrocarbon group, a halogen atom, and a C12 or less alkoxy group are mentioned. Y ¹ and Y ² may be the same or different and each represents a sulfur atom or a dialkylmethylene group having 12 or less carbon atoms. R ³ and R ⁴ may be the same or different and each represents a hydrocarbon group having 20 or less carbon atoms which may have a substituent. Preferred substituents include alkoxy groups having 12 or less carbon atoms, carboxyl groups, and sulfo groups. R ⁵ , R ⁶ , R ⁷ and R ⁸ may be the same or different and each represents a hydrogen atom or a hydrocarbon group having 12 or less carbon atoms. From the availability of raw materials, a hydrogen atom is preferred. Za ⁻ represents a counter anion. However, Za ⁻ is not necessary when the cyanine dye represented by formula (i) has an anionic substituent in its structure and neutralization of charge is not necessary. Preferred Za ⁻ is a halogen ion, a perchlorate ion, a tetrafluoroborate ion, a hexafluorophosphate ion, and a sulfonate ion from the viewpoint of storage stability of the recording layer coating solution, and particularly preferably a perchlorate ion, a hexagonal ion. Fluorophosphate ions and aryl sulfonate ions.

Specific examples of cyanine dyes represented by formula (i) that can be suitably used in the present invention include those described in paragraph numbers [0017] to [0019] of JP-A No. 2001-133969. Can do.
Other particularly preferable examples include specific indolenine cyanine dyes described in JP-A-2002-278057.
Furthermore, the infrared absorber is preferably water-soluble, but when it is water-insoluble, it can be added by a method such as dispersion or dissolution in a mixed solvent.

  Examples of the pigment used in the present invention include commercially available pigments and color index (CI) manual, “Latest Pigment Handbook” (edited by Japan Pigment Technology Association, published in 1977), “Latest Pigment Application Technology” (CMC Publishing, 1986), “Printing Ink Technology”, CMC Publishing, 1984) can be used.

  Examples of the pigment include black pigments, yellow pigments, orange pigments, brown pigments, red pigments, purple pigments, blue pigments, green pigments, fluorescent pigments, metal powder pigments, and other polymer-bonded dyes. Specifically, insoluble azo pigments, azo lake pigments, condensed azo pigments, chelate azo pigments, phthalocyanine pigments, anthraquinone pigments, perylene and perinone pigments, thioindigo pigments, quinacridone pigments, dioxazine pigments, isoindolinone pigments In addition, quinophthalone pigments, dyed lake pigments, azine pigments, nitroso pigments, nitro pigments, natural pigments, fluorescent pigments, inorganic pigments, carbon black, and the like can be used. Among these pigments, carbon black is preferable.

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

  The particle size of the pigment is preferably in the range of 0.01 μm to 10 μm, more preferably in the range of 0.05 μm to 1 μm, and particularly preferably in the range of 0.1 μm to 1 μm. Within this range, good stability of the pigment dispersion in the image recording layer coating solution and good uniformity of the image recording layer can be obtained.

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

The addition of these infrared absorbers to the image recording layer is preferably made the minimum necessary amount in order to suppress side effects that inhibit the polymerization reaction.

  These infrared absorbers are added in a proportion of 0.001 to 50% by mass, preferably 0.005 to 30% by mass, particularly preferably 0.01 to 10% by mass, based on the total solid content of the image recording layer. Can do. Within this range, high sensitivity can be obtained without adversely affecting the uniformity and film strength of the image recording layer.

  Among these infrared absorbers described above, a preferable dye is a cyanine dye represented by the general formula (i).

[(B) polymerization initiator]
The polymerization generator used in the present invention is a compound that generates radicals by light, heat, or both, and initiates and accelerates polymerization of a compound having a polymerizable unsaturated group. As the polymerization generator that can be used in the present invention, a known thermal polymerization initiator, a compound having a bond with a small bond dissociation energy, a photopolymerization initiator, or the like can be used, and a radical that is suitably used in the present invention is generated. The compound to be used refers to a compound that initiates and accelerates polymerization of a compound having a polymerizable unsaturated group by generating radicals by thermal energy. As the thermal radical generator according to the present invention, a known polymerization initiator, a compound having a bond with a small bond dissociation energy, or the like can be appropriately selected and used. Moreover, the compound which generate | occur | produces a radical can be used individually or in combination of 2 or more types.
Examples of the compound that generates radicals include organic halogenated compounds, carbonyl compounds, organic peroxide compounds, azo polymerization initiators, azide compounds, metallocene compounds, hexaarylbiimidazole compounds, organic boric acid compounds, disulfonic acid compounds, Examples include oxime ester compounds and onium salt compounds.

  Specific examples of the organic halogenated compound include Wakabayashi et al., “Bull Chem. Soc Japan” 42, 2924 (1969), US Pat. No. 3,905,815, Japanese Examined Patent Publication No. 46-4605, JP-A 48-36281, JP-A 55-32070, JP-A 60-239736, JP-A 61-169835, JP-A 61-169837, JP-A 62-58241, JP 62-212401, JP-A 63-70243, JP-A 63-298339, P. Examples include compounds described in Hutt “Journal of Heterocyclic Chemistry” 1 (No 3), (1970), and in particular, an oxazole compound substituted with a trihalomethyl group: S-triazine compound.

More preferably, an s-triazine derivative having at least one mono, di, or trihalogen-substituted methyl group bonded to the s-triazine ring, specifically, for example, 2,4,6-tris (monochloromethyl)- s-triazine, 2,4,6-tris (dichloromethyl) -s-triazine, 2,4,6-tris (trichloromethyl) -s-triazine, 2-methyl-4,6-bis (trichloromethyl)- s-triazine, 2-n-propyl-4,6-bis (trichloromethyl) -s-triazine, 2- (α, α, β-trichloroethyl) -4,6-bis (trichloromethyl) -s-triazine 2-phenyl-4,6-bis (trichloromethyl) -s-triazine, 2- (p-methoxyphenyl) -4,6-bis (trichloromethyl) -s-triazine, -(3,4-epoxyphenyl) -4,6-bis (trichloromethyl) -s-triazine, 2- (p-chlorophenyl) -4,6-bis (trichloromethyl) -s-triazine, 2- [1 -(P-methoxyphenyl) -2,4-butadienyl] -4,6-bis (trichloromethyl) -s-triazine, 2-styryl-4,6-bis (trichloromethyl) -s-triazine, 2- ( p-methoxystyryl) -4,6-bis (trichloromethyl) -s-triazine, 2- (pi-propyloxystyryl) -4,6-bis (trichloromethyl) -s-triazine, 2- (p -Tolyl) -4,
6-bis (trichloromethyl) -s-triazine, 2- (4-natoxynaphthyl) -4,6-bis (trichloromethyl) -s-triazine, 2-phenylthio-4,6-bis (trichloromethyl) -s- Triazine, 2-benzylthio-4,6-bis (trichloromethyl) -s-triazine, 2,4,6-tris (dibromomethyl) -s-triazine, 2,4,6-tris (tribromomethyl) -s -Triazine, 2-methyl-4,6-bis (tribromomethyl) -s-triazine, 2-methoxy-4,6-bis (tribromomethyl) -s-triazine and the like.

  Examples of the carbonyl compound include benzophenone, Michler ketone, 2-methylbenzophenone, 3-methylbenzophenone, 4-methylbenzophenone, 2-chlorobenzophenone, 4-bromobenzophenone, 2-carboxybenzophenone and other benzophenone derivatives, 2,2-dimethoxy- 2-phenylacetophenone, 2,2-diethoxyacetophenone, 1-hydroxycyclohexyl phenyl ketone, α-hydroxy-2-methylphenylpropanone, 1-hydroxy-1-methylethyl- (p-isopropylphenyl) ketone, 1- Hydroxy-1- (p-dodecylphenyl) ketone, 2-methyl- (4 ′-(methylthio) phenyl) -2-morpholino-1-propanone, 1,1,1-trichloromethyl- (p-butylphenyl) Acetophenone derivatives such as ketones, thioxanthone derivatives such as thioxanthone, 2-ethylthioxanthone, 2-isopropylthioxanthone, 2-chlorothioxanthone, 2,4-dimethylthioxanthone, 2,4-diethylthioxanthone, 2,4-diisopropylthioxanthone, p- Examples thereof include benzoic acid ester derivatives such as ethyl dimethylaminobenzoate and ethyl p-diethylaminobenzoate.

  As the azo compound, for example, an azo compound described in JP-A-8-108621 can be used.

  Examples of the organic peroxide compound include trimethylcyclohexanone peroxide, acetylacetone peroxide, 1,1-bis (tert-butylperoxy) -3,3,5-trimethylcyclohexane, 1,1-bis (tert-butyl). Peroxy) cyclohexane, 2,2-bis (tert-butylperoxy) butane, tert-butyl hydroperoxide, cumene hydroperoxide, diisopropylbenzene hydroperoxide, 2,5-dimethylhexane-2,5-dihydro Peroxide, 1,1,3,3-tetramethylbutyl hydroperoxide, tert-butylcumyl peroxide, dicumyl peroxide, 2,5-dimethyl-2,5-di (tert-butylperoxy) hexane, , 5-Oxanoyl peroxide, succinic peroxide, benzoyl peroxide, 2,4-dichlorobenzoyl peroxide, diisopropyl peroxydicarbonate, di-2-ethylhexyl peroxydicarbonate, di-2-ethoxyethyl peroxy Dicarbonate, dimethoxyisopropyl peroxycarbonate, di (3-methyl-3-methoxybutyl) peroxydicarbonate, tert-butyl peroxyacetate, tert-butyl peroxypivalate, tert-butyl peroxyneodecanoate, tert-butyl peroxyoctanoate, tert-butyl peroxylaurate, tersyl carbonate, 3,3 ′, 4,4′-tetra- (t-butylperoxycarbonyl) benzophenone, 3,3 ′, 4 '-Tetra- (t-hexylperoxycarbonyl) benzophenone, 3,3', 4,4'-tetra- (p-isopropylcumylperoxycarbonyl) benzophenone, carbonyldi (t-butylperoxydihydrogen diphthalate) , Carbonyldi (t-hexylperoxydihydrogen diphthalate) and the like.

  Examples of the metallocene compound include JP-A-59-152396, JP-A-61-151197, JP-A-63-41484, JP-A-2-249, JP-A-2-4705, Various titanocene compounds described in JP-A-5-83588, such as di-cyclopentadienyl-Ti-bis-phenyl, di-cyclopentadienyl-Ti-bis-2,6-difluorophen-1-yl, Di-cyclopentadienyl-Ti-bis-2,4-di-fluorophen-1-yl, di-cyclopentadienyl-Ti-bis-2,4,6-trifluorophen-1-yl, di- -Cyclopentadienyl-Ti-bis-2,3,5,6-tetrafluorophen-1-yl, di-cyclopentadienyl-Ti-bis-2,3,4,5,6-penta Fluorophen-1-yl, di-methylcyclopentadienyl-Ti-bis-2,6-difluorophen-1-yl, di-methylcyclopentadienyl-Ti-bis-2,4,6-trifluoropheny -1-yl, di-methylcyclopentadienyl-Ti-bis-2,3,5,6-tetrafluorophen-1-yl, di-methylcyclopentadienyl-Ti-bis-2,3,4 , 5,6-pentafluorophen-1-yl, iron-arene complexes described in JP-A-1-304453 and JP-A-1-152109, and the like.

  Examples of the hexaarylbiimidazole compound include JP-B-6-29285, U.S. Pat. Nos. 3,479,185, 4,311,783, and 4,622,286. And, specifically, 2,2′-bis (o-chlorophenyl) -4,4 ′, 5,5′-tetraphenylbiimidazole, 2,2′-bis (o-bromophenyl) )) 4,4 ′, 5,5′-tetraphenylbiimidazole, 2,2′-bis (o, p-dichlorophenyl) -4,4 ′, 5,5′-tetraphenylbiimidazole, 2,2 ′ -Bis (o-chlorophenyl) -4,4 ', 5,5'-tetra (m-methoxyphenyl) biidazole, 2,2'-bis (o, o'-dichlorophenyl) -4,4', 5,5 '-Tetraphenylbiimidazole, 2, 2' Bis (o-nitrophenyl) -4,4 ′, 5,5′-tetraphenylbiimidazole, 2,2′-bis (o-methylphenyl) -4,4 ′, 5,5′-tetraphenylbiimidazole 2,2′-bis (o-trifluorophenyl) -4,4 ′, 5,5′-tetraphenylbiimidazole and the like.

  Examples of the organic borate compounds include JP-A-62-143044, JP-A-62-1050242, JP-A-9-188585, JP-A-9-188686, JP-A-9-188710, and JP-A-9-188710. 2000-131837, Japanese Patent Application Laid-Open No. 2002-107916, Japanese Patent No. 2764769, Japanese Patent Application Laid-Open No. 2002-116539, and Kunz, Martin “Rad Tech'98. Proceeding April 19-22, 1998, Chicago”, etc. Organoboron salts described in JP-A-6-157623, JP-A-6-175564, JP-A-6-175561, and organic boron oxosulfonium complexes, No. 175554, JP-A-6-175553 Organoboron iodonium complexes described in JP-A-9-188710, organoboron phosphonium complexes described in JP-A-9-348710, JP-A-7-128785, JP-A-7-140589, JP-A-7- Specific examples include organoboron transition metal coordination complexes such as those described in Japanese Patent No. 306527 and Japanese Patent Laid-Open No. 7-292014.

  Examples of the disulfone compound include compounds described in JP-A Nos. 61-166544 and 2002-328465.

Examples of the oxime ester compounds include JCS Perkin II (1979) 1653-1660), JCS
Perkin II (1979) 156-162, Journal of Photopolymer Science and Technology (1995) 202-232, compounds described in JP 2000-66385 A, compounds described in JP 2000-80068 A, and the like. Is the following compound.

  Examples of the onium salt compound include S.I. I. Schlesinger, Photogr. Sci. Eng. , 18, 387 (1974), T.A. S. Bal et al, Polymer, 21, 423 (1980), diazonium salts described in U.S. Pat. No. 4,069,055, ammonium salts described in JP-A-4-365049, U.S. Pat. No. 4,069, No. 055, No. 4,069,056, phosphonium salts described in European Patent Nos. 104 and 143, U.S. Pat. Nos. 339,049 and 410,201, JP -150848, JP-A-2-296514, iodonium salts, European Patent Nos. 370,693, 390,214, 233,567, 297,443, 297,442, U.S. Pat.Nos. 4,933,377, 161,811, 410,201, 339,049, 4,760,013, 4,734,4 No. 44, No. 2,833,827, German Patent Nos. 2,904,626, 3,604,580, and 3,604,581, the sulfonium salts described in J. Pat. V. Crivello et al, Macromolecules, 10 (6), 1307 (1977), J. MoI. V. Crivello et al, J.A. Polymer Sci. , Polymer Chem. Ed. , 17, 1047 (1979), a selenonium salt described in C.I. S. Wen et al, Teh, Proc. Conf. Rad. Curing ASIA, p478 Tokyo, Oct (1988), and onium salts such as arsonium salts.

In particular, from the viewpoint of reactivity and stability, the above oxime ester compounds, diazonium salts, iodonium salts, and sulfonium salts are exemplified. In the present invention, these onium salts function not as acid generators but as ionic radical polymerization initiators.
The onium salts suitably used in the present invention are onium salts represented by the following general formulas (RI-I) to (RI-III).

In the formula (RI-I), Ar ₁₁ represents an aryl group having 20 or less carbon atoms which may have 1 to 6 substituents, and preferred substituents include alkyl groups having 1 to 12 carbon atoms and carbon numbers. 1-12 alkenyl group, C1-C12 alkynyl group, C1-C12 aryl group, C1-C12 alkoxy group, C1-C12 aryloxy group, halogen atom, C1-C1 12 alkylamino groups, C1-C12 dialkylamino groups, C1-C12 alkylamide groups or arylamide groups, carbonyl groups, carboxyl groups, cyano groups, sulfonyl groups, C1-C12 thioalkyl groups And a thioaryl group having 1 to 12 carbon atoms. Z ₁₁ ^- represents a monovalent anion, a halogen ion, perchlorate ion, hexafluorophosphate ion, tetrafluoroborate ion, sulfonate ion, sulfinate ion, thiosulfonate ion, a sulfate ion, stability From the surface, perchlorate ion, hexafluorophosphate ion, tetrafluoroborate ion, sulfonate ion, and sulfinate ion are preferable.

In the formula (RI-II), Ar ₂₁ and Ar ₂₂ each independently represents an aryl group having 20 or less carbon atoms which may have 1 to 6 substituents, and preferred substituents have 1 to 12 carbon atoms. Alkyl group, alkenyl group having 1 to 12 carbon atoms, alkynyl group having 1 to 12 carbon atoms, aryl group having 1 to 12 carbon atoms, alkoxy group having 1 to 12 carbon atoms, aryloxy group having 1 to 12 carbon atoms, halogen atom , C1-C12 alkylamino group, C1-C12 dialkylamino group, C1-C12 alkylamide group or arylamide group, carbonyl group, carboxyl group, cyano group, sulfonyl group, carbon number 1 -12 thioalkyl group and C1-C12 thioaryl group are mentioned. Z ₂₁ ^- represents a monovalent anion, a halogen ion, perchlorate ion, hexafluorophosphate ion, tetrafluoroborate ion, sulfonate ion, sulfinate ion, thiosulfonate ion, sulfate ion, a carboxylic acid ion From the viewpoints of stability and reactivity, perchlorate ions, hexafluorophosphate ions, tetrafluoroborate ions, sulfonate ions, sulfinate ions, and carboxylate ions are preferable.

In the formula (RI-III), R ₃₁ , R ₃₂ , and R ₃₃ each independently represent an aryl group having 20 or less carbon atoms, an alkyl group, an alkenyl group, or an alkynyl group that may have 1 to 6 substituents. In view of reactivity and stability, an aryl group is desirable. Preferred substituents include alkyl groups having 1 to 12 carbon atoms, alkenyl groups having 1 to 12 carbon atoms, alkynyl groups having 1 to 12 carbon atoms, aryl groups having 1 to 12 carbon atoms, alkoxy groups having 1 to 12 carbon atoms, C1-C12 aryloxy group, halogen atom, C1-C12 alkylamino group, C1-C12 dialkylamino group, C1-C12 alkylamide group or arylamide group, carbonyl group, carboxyl Group, a cyano group, a sulfonyl group, a thioalkyl group having 1 to 12 carbon atoms, and a thioaryl group having 1 to 12 carbon atoms. Z ₃₁ ^- represents a monovalent anion, a halogen ion, perchlorate ion, hexafluorophosphate ion, tetrafluoroborate ion, sulfonate ion, sulfinate ion, thiosulfonate ion, sulfate ion, a carboxylic acid ion From the viewpoints of stability and reactivity, perchlorate ion, hexafluorophosphate ion, tetrafluoroborate ion, sulfonate ion, sulfinate ion, and carboxylate ion are preferable. In particular, the carboxyl described in JP-A-2001-343742 is preferable. Acid ions, more preferably carboxylate ions described in JP-A No. 2002-148790 are preferred.

  Specific examples of the polymerization initiator that can be applied to the present invention are listed below, but are not limited thereto.

  These polymerization initiators are added in a proportion of 0.1 to 50% by mass, preferably 0.5 to 30% by mass, particularly preferably 1 to 20% by mass, based on the total solid content constituting the image recording layer. Can do. Within this range, good sensitivity and good stain resistance of the non-image area during printing can be obtained. These polymerization initiators may be used alone or in combination of two or more. Moreover, these polymerization initiators may be added to the same layer as other components, or another layer may be provided and added thereto.

[(C) Polymerizable compound]
The polymerizable compound that can be used in the image recording layer in the present invention is an addition polymerizable compound having at least one ethylenically unsaturated double bond, and has at least one terminal ethylenically unsaturated bond, preferably two. It is selected from the compounds having the above. Such a compound group is widely known in the industrial field, and can be used without any particular limitation in the present invention. These have chemical forms such as monomers, prepolymers, i.e. dimers, trimers and oligomers, or mixtures thereof and copolymers thereof. Examples of monomers and copolymers thereof include unsaturated carboxylic acids (for example, acrylic acid, methacrylic acid, itaconic acid, crotonic acid, isocrotonic acid, maleic acid, etc.), and esters and amides thereof. In this case, an ester of an unsaturated carboxylic acid and an aliphatic polyhydric alcohol compound, or an amide of an unsaturated carboxylic acid and an aliphatic polyvalent amine compound is used. In addition, an addition reaction product of an unsaturated carboxylic acid ester or amide having a nucleophilic substituent such as a hydroxyl group, amino group or mercapto group with a monofunctional or polyfunctional isocyanate or epoxy, and monofunctional or polyfunctional A dehydration condensation reaction product with a functional carboxylic acid is also preferably used. Further, an addition reaction product of an unsaturated carboxylic acid ester or amide having an electrophilic substituent such as an epoxy group or an epoxy group with a monofunctional or polyfunctional alcohol, amine or thiol, a halogen group or In addition, a substitution reaction product of an unsaturated carboxylic acid ester or amide having a leaving substituent such as a tosyloxy group and a monofunctional or polyfunctional alcohol, amine or thiol is also suitable. As another example, it is also possible to use a group of compounds substituted with unsaturated phosphonic acid, styrene, vinyl ether or the like instead of the unsaturated carboxylic acid.

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

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

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

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

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

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

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

  Also, urethane acrylates such as those described in JP-A-51-37193, JP-B-2-32293, JP-B-2-16765, JP-B-58-49860, JP-B-56- Urethane compounds having an ethylene oxide skeleton described in Japanese Patent No. 17654, Japanese Patent Publication No. 62-39417, and Japanese Patent Publication No. 62-39418 are also suitable. Furthermore, addition polymerizable compounds having an amino structure or a sulfide structure in the molecule described in JP-A-63-277653, JP-A-63-260909, and JP-A-1-105238 are used. Depending on the case, it is possible to obtain a photopolymerizable composition excellent in the photosensitive speed.

  Other examples include polyester acrylates, epoxy resins and (meth) acrylic acid as described in JP-A-48-64183, JP-B-49-43191, JP-B-52-30490, and JP-A-52-30490. Mention may be made of polyfunctional acrylates and methacrylates such as reacted epoxy acrylates. In addition, specific unsaturated compounds described in JP-B-46-43946, JP-B-1-40337, JP-B-1-40336, and vinylphosphonic acid compounds described in JP-A-2-25493 are also included. Can be mentioned. In some cases, a structure containing a perfluoroalkyl group described in JP-A-61-22048 is preferably used. Furthermore, Journal of Japan Adhesion Association vol. 20, no. 7, pages 300 to 308 (1984), which are introduced as photocurable monomers and oligomers, can also be used.

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

  The polymerizable compound is used in the image recording layer in an amount of preferably 5 to 80% by mass, more preferably 25 to 75% by mass. These may be used alone or in combination of two or more. In addition, the usage of the polymerizable compound can be arbitrarily selected from the viewpoint of polymerization inhibition with respect to oxygen, resolution, fogging, refractive index change, surface adhesiveness, etc. The layer construction and coating method such as undercoating and overcoating can also be carried out.

[(D) Binder polymer]
In the present invention, a binder polymer is preferably used in order to improve the film characteristics of the image recording layer and the 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 ethylenically unsaturated bonds in the side chain of the molecule are polymers of esters or amides of acrylic acid or methacrylic acid, at least of the residue of the ester or amide (-COOR or CONHR R) Mention may be made of polymers having some ethylenically unsaturated bonds.

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

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 -CH ₂ CH = CH ₂ and CH ₂ CH (wherein, X represents a dicyclopentadienyl residue.) ₂ O-X and the like.
Specific examples of the amide residue include —CH 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.

  The binder polymer having crosslinkability, for example, has a free radical (polymerization initiation radical or a growth radical in the polymerization process of the polymerizable compound) added to the crosslinkable functional group, and the polymerization chain of the polymerizable compound is formed directly between the 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 together, thereby causing cross-linking between polymer molecules. 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.

Further, from the viewpoint of improving the on-press developability of the image recording layer unexposed portion, 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. Therefore, 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, hydroxyethyl methacrylate homopolymers and copolymers, hydroxyethyl acrylate homopolymers and copolymers, hydroxypropyl methacrylate homopolymers and copolymers, hydroxypropyl acrylate homopolymers and copolymers, hydroxybutyl methacrylate homopolymers Polymers and copolymers, homopolymers and copolymers of hydroxybutyl acrylate, polyethylene glycol , 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 Methacrylamide homopolymers and polymers, N-methylolacrylamide homopolymers and copolymers, polyvinylpyrrolidone, alcohol-soluble nylon, polyether of 2,2-bis- (4-hydroxyphenyl) -propane and epichlorohydrin, etc. Is mentioned.

  The binder polymer preferably has a mass average molecular weight of 5,000 or more, more preferably 10,000 to 300,000, and a number average molecular weight of 1,000 or more, preferably 2000 to 250,000. More preferred. The polydispersity (mass average molecular weight / number average molecular weight) is preferably 1.1 to 10.

The binder polymer may be a random polymer, a block polymer, a graft polymer, or the like, but is preferably a random polymer.
Such a binder polymer can be synthesized by a conventionally known method. The binder polymer having a crosslinkable group in the side chain can be easily synthesized by radical polymerization or polymer reaction.

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 and more preferably 20 to 80% by mass with respect to the total solid content of the image recording layer. 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.

[Other components of image recording layer]
In the image recording layer of the present invention, components other than the above (A) to (D), for example, surfactant, colorant, print-out agent, polymerization inhibitor (thermal polymerization inhibitor), higher fatty acid derivative, plasticizer Inorganic fine particles, low molecular weight hydrophilic compounds, and the like can be contained.

<Surfactant>
In the present invention, it is preferable to use a surfactant in the image recording layer in order to promote on-press developability at the start of printing and to improve the coated surface state. Examples of the surfactant include nonionic surfactants, anionic surfactants, cationic surfactants, amphoteric surfactants, and fluorosurfactants. Surfactant may be used independently and may be used in combination of 2 or more type.

  The nonionic surfactant used for this invention is not specifically limited, A conventionally well-known thing can be used. For example, polyoxyethylene alkyl ethers, polyoxyethylene alkyl phenyl ethers, polyoxyethylene polystyryl phenyl ethers, polyoxyethylene polyoxypropylene alkyl ethers, glycerin fatty acid partial esters, sorbitan fatty acid partial esters, pentaerythritol Fatty acid partial esters, propylene glycol 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 ester, trialkylamine oxide, polyethylene glycol, copolymers of polyethylene glycol and polypropylene glycol.

  The anionic surfactant used in the present invention is not particularly limited, and conventionally known anionic surfactants can be used. For example, fatty acid salts, abietic acid salts, hydroxyalkane sulfonates, alkane sulfonates, dialkyl sulfosuccinate esters, linear alkyl benzene sulfonates, branched alkyl benzene sulfonates, alkyl naphthalene sulfonates, alkyl phenoxy poly Oxyethylene propyl sulfonates, polyoxyethylene alkyl sulfophenyl ether salts, N-methyl-N-oleyl taurine sodium salt, N-alkyl sulfosuccinic acid monoamide disodium salt, petroleum sulfonates, sulfated beef oil, fatty acid alkyl esters Sulfates, alkyl sulfates, polyoxyethylene alkyl ether sulfates, fatty acid monoglyceride sulfates, polyoxyethylene alcohol Ruphenyl ether sulfates, polyoxyethylene styryl phenyl ether sulfates, alkyl phosphates, polyoxyethylene alkyl ether phosphates, polyoxyethylene alkyl phenyl ether phosphates, styrene / maleic anhydride Examples thereof include partial saponification products of polymers, partial saponification products of olefin / maleic anhydride copolymers, and naphthalene sulfonate formalin condensates.

The cationic surfactant used in the present invention is not particularly limited, and conventionally known cationic surfactants can be used. Examples thereof include alkylamine salts, quaternary ammonium salts, polyoxyethylene alkylamine salts, and polyethylene polyamine derivatives.
The amphoteric surfactant used in the present invention is not particularly limited, and conventionally known amphoteric surfactants can be used. Examples thereof include carboxybetaines, aminocarboxylic acids, sulfobetaines, aminosulfuric esters, and imidazolines.

  Of the above surfactants, the term “polyoxyethylene” can be read as “polyoxyalkylene” such as polyoxymethylene, polyoxypropylene, polyoxybutylene, etc. These surfactants can also be used.

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

Surfactant can be used individually or in combination of 2 or more types.
The surfactant is preferably contained in the image recording layer in an amount of 0.001 to 10% by mass, and more preferably 0.01 to 5% by mass.

<Colorant>
In the image recording layer of the present invention, a dye having a large absorption in the visible light region can be used as an image colorant. Specifically, Oil Yellow # 101, Oil Yellow # 103, Oil Pink # 312, Oil Green BG, Oil Blue BOS, Oil Blue # 603, Oil Black BY, Oil Black BS, Oil Black T-505 (orientated chemistry) Manufactured by Kogyo Co., Ltd.), Victoria Pure Blue, Crystal Violet (CI42555), Methyl Violet (CI42535), Ethyl Violet, Rhodamine B (CI145170B), Malachite Green (CI42000), Methylene Blue (CI522015), etc., and JP-A-62-2 And dyes described in Japanese Patent No. 293247. In addition, pigments such as phthalocyanine pigments, azo pigments, carbon black, and titanium oxide can also be suitably used.

<Bakeout agent>
In the image recording layer of the present invention, a compound that is discolored by an acid or a radical can be added to produce a printout image. As such a compound, for example, various dyes such as diphenylmethane, triphenylmethane, thiazine, oxazine, xanthene, anthraquinone, iminoquinone, azo, and azomethine are effectively used.

  Specific examples include brilliant green, ethyl violet, methyl green, crystal violet, basic fuchsin, methyl violet 2B, quinaldine red, rose bengal, methanyl yellow, thymol sulfophthalein, xylenol blue, methyl orange, paramethyl red, Congo Fred, Benzopurpurin 4B, α-Naphthyl Red, Nile Blue 2B, Nile Blue A, Methyl Violet, Malachide Green, Parafuchsin, Victoria Pure Blue BOH [manufactured by Hodogaya Chemical Co., Ltd.], Oil Blue # 603 [Orient Chemical Kogyo Co., Ltd.], Oil Pink # 312 [Orient Chemical Co., Ltd.], Oil Red 5B [Orient Chemical Co., Ltd.], Oil Scarlet # 308 [Orient Gaku Kogyo Co., Ltd.], Oil Red OG [Orient Chemical Co., Ltd.], Oil Red RR [Orient Chemical Co., Ltd.], Oil Green # 502 [Orient Chemical Co., Ltd.], Spiron Red BEH Special [made by Hodogaya Chemical Co., Ltd.], m-cresol purple, cresol red, rhodamine B, rhodamine 6G, sulforhodamine B, auramine, 4-p-diethylaminophenyliminonaphthoquinone, 2-carboxyanilino-4-p- Diethylaminophenyliminonaphthoquinone, 2-carboxystearylamino-4-pN, N-bis (hydroxyethyl) amino-phenyliminonaphthoquinone, 1-phenyl-3-methyl-4-p-diethylaminophenylimino-5-pyrazolone, 1-β-naphthyl-4- - dyes and p of diethylamino phenyl imino-5-pyrazolone, p ', p "- hexamethyl triamnotriphenylmethane (leuco crystal violet), and a leuco dye such as Pergascript Blue SRB (manufactured by Ciba-Geigy).

  In addition to the above, a leuco dye known as a material for thermal paper or pressure-sensitive paper is also suitable. Specific examples include crystal violet lactone, malachite green lactone, benzoylleucomethylene blue, 2- (N-phenyl-N-methylamino) -6- (Np-tolyl-N-ethyl) amino-fluorane, 2-anilino. -3-methyl-6- (N-ethyl-p-toluidino) fluorane, 3,6-dimethoxyfluorane, 3- (N, N-diethylamino) -5-methyl-7- (N, N-dibenzylamino) ) -Fluorane, 3- (N-cyclohexyl-N-methylamino) -6-methyl-7-anilinofluorane, 3- (N, N-diethylamino) -6-methyl-7-anilinofluorane, 3 -(N, N-diethylamino) -6-methyl-7-xylidinofluorane, 3- (N, N-diethylamino) -6-methyl-7-chloro Fluorane, 3- (N, N-diethylamino) -6-methoxy-7-aminofluorane, 3- (N, N-diethylamino) -7- (4-chloroanilino) fluorane, 3- (N, N-diethylamino) -7-chlorofluorane, 3- (N, N-diethylamino) -7-benzylaminofluorane, 3- (N, N-diethylamino) -7,8-benzofluorane, 3- (N, N-dibutyl) Amino) -6-methyl-7-anilinofluorane, 3- (N, N-dibutylamino) -6-methyl-7-xylidinofluorane, 3-piperidino-6-methyl-7-anilinofluorane 3-pyrrolidino-6-methyl-7-anilinofluorane, 3,3-bis (1-ethyl-2-methylindol-3-yl) phthalide, 3,3-bis (1-n-butyl- -Methylindol-3-yl) phthalide, 3,3-bis (p-dimethylaminophenyl) -6-dimethylaminophthalide, 3- (4-diethylamino-2-ethoxyphenyl) -3- (1-ethyl- 2-methylindol-3-yl) -4-zaphthalide, 3- (4-diethylaminophenyl) -3- (1-ethyl-2-methylindol-3-yl) phthalide, and the like.

  It is preferable to add the dye which changes color by an acid or a radical to the image recording layer at a ratio of 0.01 to 10% by mass.

<Thermal polymerization inhibitor>
In order to prevent unnecessary thermal polymerization of the polymerizable compound (C) during production or storage of the image recording layer, a small amount of a thermal polymerization inhibitor is preferably added to the image recording layer in the present invention.
Examples of the thermal polymerization inhibitor include hydroquinone, p-methoxyphenol, di-t-butyl-p-cresol, pyrogallol, t-butylcatechol, benzoquinone, 4,4′-thiobis (3-methyl-6-t- (Butylphenol), 2,2'-methylenebis (4-methyl-6-tert-butylphenol), N-nitroso-N-phenylhydroxylamine aluminum salt are preferred.
The thermal polymerization inhibitor is preferably contained in the image recording layer in an amount of about 0.01 to about 5% by mass.

<Higher fatty acid derivatives, etc.>
In the image recording layer of the present invention, a higher fatty acid derivative such as behenic acid or behenic acid amide or the like is added to prevent polymerization inhibition due to oxygen, and the surface of the image recording layer is dried during coating. It may be unevenly distributed. The amount of the higher fatty acid derivative added is preferably about 0.1 to about 10% by mass with respect to the total solid content of the image recording layer.

<Plasticizer>
The image recording layer in the invention may contain a plasticizer in order to improve the on-press developability.
Examples of the plasticizer include phthalates such as dimethyl phthalate, diethyl phthalate, dibutyl phthalate, diisobutyl phthalate, dioctyl phthalate, octyl capryl phthalate, dicyclohexyl phthalate, ditridecyl phthalate, butyl benzyl phthalate, diisodecyl phthalate, diallyl phthalate; Glycol esters such as glycol phthalate, ethyl phthalyl ethyl glycolate, methyl phthalyl ethyl glycolate, butyl phthalyl butyl glycolate, triethylene glycol dicaprylate; Phosphate esters such as tricresyl phosphate and triphenyl phosphate Diisobutyl adipate, dioctyl adipate, dimethyl sebacate, dibutyl sebacate, dioct Ruazereto, aliphatic dibasic acid esters such as dibutyl maleate; polyglycidyl methacrylate, triethyl citrate, glycerin triacetyl ester, butyl laurate in.
The plasticizer is preferably contained in the image recording layer at a ratio of about 30% by mass or less.

<Inorganic fine particles>
The image recording layer in the present invention may contain inorganic fine particles in order to enhance the interfacial adhesiveness by surface roughening, improve the cured film strength of the image area, and improve the on-press developability of the non-image area.
As the inorganic fine particles, for example, silica, alumina, magnesium oxide, titanium oxide, magnesium carbonate, calcium alginate, or a mixture thereof is preferably exemplified.
The inorganic fine particles preferably have an average particle size of 5 nm to 10 μm, and more preferably 0.5 μm to 3 μm. Within the above range, it is possible to form a non-image portion having excellent hydrophilicity that is stably dispersed in the image recording layer, sufficiently retains the film strength of the image recording layer, and hardly causes stains during printing.
The inorganic fine particles as described above can be easily obtained as a commercial product such as a colloidal silica dispersion.
The content of the inorganic fine particles is preferably 20% by mass or less, and more preferably 10% by mass or less, based on the total solid content of the image recording layer.

<Low molecular hydrophilic compound>
The image recording layer in the invention may contain a hydrophilic low molecular weight compound for improving on-press developability. Examples of hydrophilic low-molecular compounds include water-soluble organic compounds such as ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, dipropylene glycol, tripropylene glycol and the like, and ether or ester derivatives thereof, glycerin, Polyhydroxys such as pentaerythritol, organic amines such as triethanolamine and diethanolamine monoethanolamine and salts thereof, organic sulfonic acids such as toluenesulfonic acid and benzenesulfonic acid and salts thereof, organic phosphonic acids such as phenylphosphonic acid and the like Examples thereof include organic carboxylic acids such as salts, tartaric acid, oxalic acid, citric acid, malic acid, lactic acid, gluconic acid and amino acids, and salts thereof.

(Formation of image recording layer)
In the present invention, as a method of incorporating the image recording layer constituents into the image recording layer,
Several embodiments can be used. One is a molecular dispersion type image recording layer in which the constituent components are dissolved and applied in an appropriate solvent as described in JP-A-2002-287334, for example. In another embodiment, for example, as described in JP-A-2001-277740 and JP-A-2001-277742, all or part of the components (A) to (D) are encapsulated in a microcapsule. It is a microcapsule type image recording layer to be contained in the recording layer. Further, in the microcapsule type image recording layer, the constituent component can be contained outside the microcapsule. Here, it is preferable that the microcapsule-type image recording layer includes a hydrophobic constituent component in the microcapsule and a hydrophilic constituent component outside the microcapsule. In order to obtain better on-press developability, it is advantageous that the image recording layer is a microcapsule type image recording layer.

  As a method of microencapsulating the above-mentioned image recording layer constituent components, known methods can be applied. For example, as a method for producing microcapsules, a method using coacervation found in U.S. Pat. Nos. 2,800,547 and 2,800,498, U.S. Pat. No. 3,287,154, JP-B-38-19574, 42-446 by the interfacial polymerization method, US Pat. No. 3,418,250, US Pat. No. 3,660,304 by precipitation of polymer, US Pat. No. 3,796,669, isocyanate polyol A method using a wall material, a method using an isocyanate wall material found in US Pat. No. 3,914,511, and a urea-formaldehyde system found in US Pat. Nos. 4,001,140, 4,087,376 and 4,089,802. Or urea formaldehyde-resorcinol A method using a wall forming material, a method using a wall material such as melamine-formaldehyde resin, hydroxycellulose, etc. found in US Pat. No. 4,025,445, and Japanese Patent Publication Nos. 36-9163 and 51-9079. In situ method by monomer polymerization, spray drying method found in British Patent No. 930422, US Pat. No. 3,111,407, electrolytic dispersion cooling method seen in British Patent Nos. 952807, 967074, etc. However, it is not limited to these.

  A preferable microcapsule wall used in the present invention has a three-dimensional cross-linking and has a property of swelling with a solvent. From such a viewpoint, the wall material of the microcapsule is preferably polyurea, polyurethane, polyester, polycarbonate, polyamide, and a mixture thereof, and particularly preferably polyurea and polyurethane. Moreover, you may introduce | transduce into the microcapsule wall the compound which has crosslinkable functional groups, such as the said ethylenically unsaturated bond which can introduce | transduce the binder polymer.

Such microcapsules may be combined with each other by heat or may not be combined. In short, among the microcapsule inclusions, the one that exudes to the surface of the microcapsule or the outside of the microcapsule at the time of application, or the one that enters the microcapsule wall may cause a chemical reaction by heat. Moreover, you may react with the added hydrophilic resin or the added low molecular weight compound. Furthermore, two or more types of microcapsules may be reacted with each other by providing functional groups that react with each other with different functional groups. Therefore, it is preferable for image formation that the microcapsules are fused and united with heat, but it is not essential.
The addition amount of the microcapsules to the image recording layer (image forming layer) is preferably 50% by mass or more, and more preferably 60 to 95% by mass in terms of solid content in terms of solid content. Within this range, good sensitivity and good printing durability can be obtained simultaneously with good developability.

  The average particle size of the microcapsules is preferably 0.01 to 3.0 μm. 0.05-2.0 micrometers is further more preferable, and 0.10-1.0 micrometer is especially preferable. Within this range, good resolution and stability over time can be obtained.

  When the microcapsules are contained in the image recording layer of the present invention, a solvent capable of dissolving the inclusion and swelling the wall material can be added to the microcapsule dispersion medium. By such a solvent, diffusion of the encapsulated compound having a heat-reactive functional group to the outside of the microcapsule is promoted. Such a solvent depends on the microcapsule dispersion medium, the material of the microcapsule wall, the wall thickness, the inclusion, and the like, but can be easily selected from many commercially available solvents. For example, in the case of a water-dispersible microcapsule comprising a crosslinked polyurea or polyurethane wall, alcohols, ethers, acetals, esters, ketones, polyhydric alcohols, amides, amines, fatty acids and the like are preferable.

  Specific examples of the solvent include methanol, ethanol, tertiary butanol, n-propanol, tetrahydrofuran, methyl lactate, ethyl lactate, methyl ethyl ketone, propylene glycol monomethyl ether, ethylene glycol diethyl ether, ethylene glycol monomethyl ether, γ-butyrolactone, N , N-dimethylformamide, N, N-dimethylacetamide, and the like. Two or more of these solvents may be used. A solvent that does not dissolve in the microcapsule dispersion but dissolves when the solvent is mixed can also be used.

  The amount of the solvent added is determined by the combination of materials, but usually 5 to 95% by mass of the coating solution is effective, and a preferable range is 10 to 90% by mass, and a more preferable range is 15 to 85% by mass. %.

The image recording layer in the present invention is formed by preparing and applying a coating solution by dispersing or dissolving necessary constituents in a solvent using any of the above-described embodiments. Solvents used here include ethylene dichloride, cyclohexanone, methyl ethyl ketone, methanol, ethanol, propanol, ethylene glycol monomethyl ether, 1-methoxy-2-propanol, 2-methoxyethyl acetate, 1-methoxy-2-propyl acetate, dimethoxy Examples include ethane, methyl lactate, ethyl lactate, N, N-dimethylacetamide, N, N-dimethylformamide, tetramethylurea, N-methylpyrrolidone, dimethyl sulfoxide, sulfolane, γ-butyrolactone, toluene, water and the like. However, the present invention is not limited to this. These solvents are used alone or in combination. The solid content concentration of the coating solution is preferably 1 to 50% by mass.
The image recording layer of the present invention can be formed by preparing a plurality of coating solutions in which the same or different components are dispersed or dissolved in the same or different solvents, and repeating a plurality of coatings and dryings.

Image recording layer coating weight (solids) is preferably from ^{0.3~1.5g / m 2, 0.5~1.5g / m} 2 is more preferable.
Various methods can be used as a coating method. Examples thereof include bar coater coating, spin coating, spray coating, curtain coating, dip coating, air knife coating, blade coating, and roll coating.

[Overcoat layer]
The planographic printing plate precursor of the present invention can be removed with printing ink, fountain solution or both for purposes such as preventing scratches in the image recording layer, blocking oxygen, and preventing ablation during high-intensity laser exposure. An overcoat layer (protective layer) can be provided on the image recording layer.
In the present invention, the exposure is usually carried out in the atmosphere, but the overcoat layer is made up of low molecular compounds such as oxygen and basic substances present in the atmosphere that inhibit the image forming reaction caused by exposure in the image recording layer. It prevents mixing into the image recording layer and prevents an image formation reaction from being hindered by exposure in the atmosphere. Therefore, the properties desired for the overcoat layer are low permeability of low-molecular compounds such as oxygen, furthermore, good transparency of light used for exposure, and excellent adhesion to the image recording layer, And it is preferable that it can be easily removed in the on-press development process after exposure. Various studies have been made on overcoat layers having such characteristics, and are described in detail, for example, in US Pat. No. 3,458,311 and JP-A-55-49729. .

Examples of the material used for the overcoat layer include water-soluble polymer compounds that are relatively excellent in crystallinity. Specific examples include water-soluble polymers such as polyvinyl alcohol, polyvinyl pyrrolidone, acidic celluloses, gelatin, gum arabic, and polyacrylic acid. Among these, when polyvinyl alcohol (PVA) is used as a main component, the best results are obtained for basic characteristics such as oxygen barrier properties and development removability. The polyvinyl alcohol may be partially substituted with an ester, ether or acetal as long as it contains an unsubstituted vinyl alcohol unit for providing the oxygen barrier property and water solubility necessary for the overcoat layer, and part of the polyvinyl alcohol The copolymer component may be included.
Specific examples of the polyvinyl alcohol include those having a hydrolysis degree of 71 to 100% and a degree of polymerization of 300 to 2400. Specifically, for example, PVA-105, PVA-110, PVA-117, PVA-117H, PVA-120, PVA-124, PVA-124H, PVA-CS, PVA-CST, PVA manufactured by Kuraray Co., Ltd. -HC, PVA-203, PVA-204, PVA-205, PVA-210, PVA-217, PVA-220, PVA-224, PVA-217EE, PVA-217E, PVA-220E, PVA-224E, PVA-405 , PVA-420, PVA-613, and L-8.

The components of the overcoat layer (selection of PVA, use of additives, etc.), coating amount, and the like are appropriately selected in consideration of fogging, adhesion, scratch resistance, etc. in addition to oxygen barrier properties and development removability. In general, the higher the hydrolysis rate of PVA (that is, the higher the content of unsubstituted vinyl alcohol units in the overcoat layer), and the thicker the film thickness, the higher the oxygen barrier property. preferable. Further, in order to prevent unnecessary polymerization reaction during production and storage, unnecessary fogging during image exposure, image line thickening, and the like, it is preferable that the oxygen permeability is not excessively high. Accordingly, the oxygen permeability A at 25 ° C. and 1 atm is preferably 0.2 ≦ A ≦ 20 (cc / m ² · day).

  As another composition of the overcoat layer, glycerin, dipropylene glycol and the like can be added in an amount corresponding to several mass% with respect to the (co) polymer to give flexibility. Anionic surfactants such as sodium sulfonate; amphoteric surfactants such as alkylaminocarboxylates and alkylaminodicarboxylates; nonionic surfactants such as polyoxyethylene alkylphenyl ethers to (co) polymers Several mass% can be added.

  In addition, adhesion of the overcoat layer to the image recording layer, scratch resistance, and the like are extremely important in handling the lithographic printing plate precursor. That is, when an overcoat layer that is hydrophilic because it contains a water-soluble polymer compound is laminated on an image recording layer that is oleophilic, the overcoat layer is easily peeled off due to insufficient adhesion, and oxygen is removed in the peeled portion. It may cause defects such as poor film hardening due to polymerization inhibition.

On the other hand, various proposals have been made to improve the adhesion between the image recording layer and the overcoat layer. For example, JP-A-49-70702 and British Patent Application No. 1303578 disclose an acrylic emulsion, a water-insoluble vinylpyrrolidone-vinyl acetate copolymer, etc. in a hydrophilic polymer mainly composed of polyvinyl alcohol. It is described that sufficient adhesiveness can be obtained by mixing 20 to 60% by mass and laminating on an image recording layer. Any of these known techniques can be used in the present invention. The method for applying the overcoat layer is described in detail, for example, in US Pat. No. 3,458,311 and JP-A-55-49729.
Furthermore, other functions can be imparted to the overcoat layer. For example, by adding a colorant (for example, a water-soluble dye) that is excellent in the transparency of infrared rays used for exposure and that can efficiently absorb light of other wavelengths, it is safe light without causing a decrease in sensitivity. Suitability can be improved.

  The thickness of the overcoat layer is suitably from 0.1 to 5 μm, particularly preferably from 0.2 to 2 μm.

Next, the hydrophilic support used in the present invention will be described.
<Metal base>
The metal substrate used for the support of the present invention is not particularly limited, and examples thereof include iron, stainless steel, and aluminum. Among these, aluminum is preferable. An aluminum plate used as an aluminum substrate is a metal whose main component is dimensionally stable aluminum, and is made of aluminum or an aluminum alloy. In addition to a pure aluminum plate, an alloy plate containing aluminum as a main component and containing a trace amount of foreign elements, or a plastic film or paper on which aluminum or an aluminum alloy is laminated or vapor-deposited can also be used. Furthermore, a composite sheet in which an aluminum sheet is bonded to a polyethylene terephthalate film as described in Japanese Patent Publication No. 48-18327 can also be used.

  The aluminum plate used in the present invention is not particularly limited, but a pure aluminum plate is preferably used. Since completely pure aluminum is difficult to manufacture in terms of scouring techniques, it may be used that contains slightly different elements. For example, known materials described in Aluminum Handbook 4th Edition (Light Metals Association (1990)), specifically, JIS1050 material, JIS1100 material, JIS3003 material, JIS3103 material, JIS3005 material, etc. can be used. Further, the content of aluminum (Al) is 99.4 to 95% by mass, and iron (Fe), silicon (Si), copper (Cu), magnesium (Mg), manganese (Mn), zinc (Zn) Further, an aluminum plate using an aluminum alloy, a scrap aluminum material, or a secondary metal containing at least five of chromium (Cr) and titanium (Ti) within a range described later can also be used.

  In the present invention, an aluminum plate having an Al content of 95 to 99.4% by mass, which is cost-effective, can also be used. If the Al content exceeds 99.4% by mass, the allowable amount of impurities decreases, which may reduce the cost reduction effect. Further, if the Al content is less than 95% by mass, it contains a large amount of impurities, which may cause defects such as cracks during rolling. The Al content is more preferably 95 to 99% by mass, and particularly preferably 95 to 97% by mass.

  The content of Fe is preferably 0.3 to 1.0% by mass. Fe is an element contained in the new metal in the range of about 0.1 to 0.2% by mass, and the amount dissolved in Al is small, and most remains as an intermetallic compound. If the Fe content exceeds 1.0% by mass, cracks are likely to occur during rolling, and if it is less than 0.3% by mass, the cost reduction effect decreases, which is not preferable. A more preferable Fe content is 0.5 to 1.0 mass%.

  The Si content is preferably 0.15 to 1.0 mass%. Si is an element contained in a large amount in scrap of JIS 2000, 4000, and 6000 materials. Further, Si is an element contained in the new metal in the range of about 0.03 to 0.1% by mass and exists in a solid solution state in Al or as an intermetallic compound. When the aluminum plate is heated during the manufacturing process of the support, Si that has been dissolved may precipitate as elemental Si. It is known that simple Si and FeSi-based intermetallic compounds adversely affect the resistance to severe ink stains. Here, “severe ink stains” appear on printed paper as a result of the ink becoming more likely to adhere to the non-image area surface of the planographic printing plate when printing is interrupted many times. This refers to dot-like or annular dirt. If the Si content exceeds 1.0% by mass, for example, this may not be completely removed by a treatment with sulfuric acid (desmut treatment) described later, and if it is less than 0.15% by mass, there is a cost reduction effect. It will decrease. A more preferable Si content is 0.3 to 1.0 mass%.

  The content of Cu is preferably 0.1 to 1.0% by mass. Cu is an element contained in a lot of scraps of JIS 2000 and 4000 materials. Cu is relatively easily dissolved in Al. If the Cu content exceeds 1.0% by mass, for example, it may be impossible to completely remove this by treatment with sulfuric acid described later. If the Cu content is less than 0.1% by mass, the cost reduction effect decreases. . A more preferable Cu content is 0.3 to 1.0 mass%.

  The content of Mg is preferably 0.1 to 1.5% by mass. Mg is an element contained in a large amount in scraps of JIS 2000, 3000, 5000, and 7000 materials. In particular, it is one of the main impurity metals contained in scrap materials because it is contained in a large amount in can end materials. Mg is relatively easy to dissolve in Al and forms an intermetallic compound with Si. If the Mg content exceeds 1.5% by mass, for example, it may not be possible to remove this by treatment with sulfuric acid described later, and if it is less than 0.1% by mass, the cost reduction effect will decrease. . A more preferable Mg content is 0.5 to 1.5 mass%, and further preferably 1.0 to 1.5 mass%.

  The Mn content is preferably 0.1 to 1.5% by mass. Mn is an element contained in a large amount in scrap of JIS 3000 series materials. Mn is one of the main impurity metals contained in the scrap material because it is contained in the can body material. Mn is relatively easily dissolved in Al and forms an intermetallic compound with Al, Fe, and Si. If the content of Mn exceeds 1.5% by mass, for example, this may not be completely removed by the treatment with sulfuric acid described later, and if it is less than 0.1% by mass, the cost reduction effect is reduced. . A more preferable Mn content is 0.5 to 1.5% by mass, and further preferably 1.0 to 1.5% by mass.

  The Zn content is preferably 0.1 to 0.5% by mass. Zn is an element that is particularly abundant in JIS7000 series scrap. Zn is relatively easily dissolved in Al. If the Zn content exceeds 0.5% by mass, for example, it may not be possible to completely remove this by treatment with sulfuric acid described later, and if it is less than 0.1% by mass, the cost reduction effect will decrease. . A more preferable Zn content is 0.3 to 0.5 mass%.

  The content of Cr is preferably 0.01 to 0.1% by mass. Cr is an impurity metal contained in a small amount in JIS 5000, 6000 and 7000 scraps. If the Cr content exceeds 0.1% by mass, for example, it may not be possible to remove this by treatment with sulfuric acid described later, and if it is less than 0.01% by mass, the cost reduction effect will be reduced. . A more preferable Cr content is 0.05 to 0.1% by mass.

  The Ti content is preferably 0.03 to 0.5% by mass. Ti is an element usually added in an amount of 0.01 to 0.04% by mass as a crystal refining material. JIS 5000 series, 6000 series, and 7000 series scraps contain relatively large amounts of impurity metals. If the Ti content exceeds 0.5% by mass, for example, it may not be possible to remove this by treatment with sulfuric acid, which will be described later, and if it is less than 0.03% by mass, the cost reduction effect will decrease. . A more preferable Ti content is 0.05 to 0.5 mass%.

  The aluminum plate used in the present invention is subjected to a rolling treatment or a heat treatment as appropriate, which is cast by a conventional method using the above raw materials, and has a thickness of, for example, 0.1 to 0.7 mm. Manufactured with straightening treatment. This thickness can be appropriately changed according to the size of the printing press, the size of the printing plate, and the user's desire. In addition, as a manufacturing method of the said aluminum plate, the method which abbreviate | omitted soaking and / or annealing treatment from DC casting method, DC casting method, and the continuous casting method can be used, for example.

  The support of the present invention can be obtained by subjecting the metal substrate to a surface roughening treatment and an anodizing treatment, and further treating with an aqueous solution containing an inorganic fluorine compound and a silicate compound. The body manufacturing process may include various processes other than the roughening process, the anodizing process, and the treatment with the aqueous solution. Hereinafter, the support of the present invention will be described with reference to an example in which an aluminum plate is used as the metal substrate.

  The above aluminum plate is a degreasing process for removing the adhering rolling oil, a desmutting process for dissolving the smut on the surface of the aluminum plate, a roughening process for roughening the surface of the aluminum plate, and oxidizing the surface of the aluminum plate. It is preferable to go through an anodizing process step covered with a film, a pore wide treatment (acid treatment or alkali treatment) step, and the like. The production process of the support of the present invention preferably includes a roughening treatment (electrochemical roughening treatment) for electrochemically roughening the aluminum plate using an alternating current in an acidic aqueous solution. Moreover, the manufacturing process of the support of the present invention includes a surface of an aluminum plate in which mechanical roughening treatment, chemical etching treatment in an acid or alkaline aqueous solution, etc. are combined in addition to the electrochemical roughening treatment. A processing step may be included. The production process such as the surface roughening treatment of the support of the present invention may be a continuous process or an intermittent process, but it is preferable to use a continuous process industrially. In the present invention, the substrate is further treated with an aqueous solution containing an inorganic fluorine compound and a silicate compound, and if necessary, a support is formed through a hydrophilic surface treatment. Furthermore, an undercoat layer may be provided after forming the support, if necessary.

<Roughening treatment (graining treatment)>
First, the roughening process will be described. The aluminum plate is grained to a more preferable shape. Examples of the graining method include mechanical graining (mechanical surface roughening), chemical etching, and electrolytic grain as described in JP-A-56-28893. In addition, electrochemical graining (electrochemical roughening, electrolytic graining), which is electrochemically grained in hydrochloric acid electrolyte or nitric acid electrolyte, or the aluminum surface is scratched with metal wire Mechanical graining methods (mechanical roughening treatment) such as brush grain method, ball grain method to grain the aluminum surface with abrasive balls and abrasives, brush grain method to grain the surface with nylon brush and abrasives, etc. Can be used. These graining methods can be used alone or in combination. For example, a combination of a mechanical surface roughening treatment with a nylon brush and an abrasive and an electrolytic surface roughening treatment with a hydrochloric acid electrolytic solution or a nitric acid electrolytic solution, or a combination of a plurality of electrolytic surface roughening treatments may be mentioned. Of these, electrochemical surface roughening is preferred. Moreover, it is also preferable to perform a mechanical surface roughening process and an electrochemical surface roughening process in combination, and it is particularly preferable to perform an electrochemical surface roughening process after the mechanical surface roughening process.

  The mechanical roughening treatment is a treatment for mechanically roughening the surface of the aluminum plate using a brush or the like, and is preferably performed before the electrochemical roughening treatment described above. In a suitable mechanical surface roughening treatment, the treatment is performed with a rotating nylon brush roll having a bristle diameter of 0.07 to 0.57 mm and a slurry of an abrasive supplied to the aluminum plate surface.

The nylon brush preferably has a low water absorption rate. For example, nylon bristle 200T manufactured by Toray Industries, Inc. (6,10-nylon, softening point: 180 ° C., melting point: 212 to 214 ° C., specific gravity:
1.08 to 1.09, moisture content: 1.4 to 1.8 at 20 ° C. and relative humidity 65%, 2.2 to 2.8 at 20 ° C. and relative humidity 100%, dry tensile strength: 4.5 -6 g / d, dry tensile elongation: 20-35%, boiling water shrinkage: 1-4%, dry tensile resistance: 39-45 g / d, Young's modulus (dry): 380-440 kg / mm ² ) preferable.

  As the abrasive, known ones can be used, but silica sand, quartz, aluminum hydroxide, or a mixture thereof described in JP-A-6-135175 and JP-B-50-40047 is used. Is preferred.

  As a slurry liquid, what has a specific gravity in the range of 1.05-1.3 is preferable. Examples of the method of supplying the slurry liquid to the aluminum plate surface include a method of spraying the slurry liquid, a method of using a wire brush, and a method of transferring the surface shape of the uneven roll to the aluminum plate. Moreover, you may use the method described in Unexamined-Japanese-Patent No. 55-074898, 61-162351, 63-104889. Furthermore, as described in JP-A-9-509108, an aluminum plate in an aqueous slurry comprising a mixture of particles made of alumina and quartz at a mass ratio in the range of 95: 5 to 5:95. A method of brush polishing the surface can also be used. The average particle size of the mixture at this time is preferably in the range of 1 to 40 μm, particularly 1 to 20 μm.

The electrochemical surface roughening treatment is a step of electrochemically roughening the surface of the aluminum plate in an acidic aqueous solution through an alternating current using the aluminum plate as an electrode. Is different. In the present invention, in the electrochemical surface roughening treatment, the amount of electricity when the aluminum plate becomes a cathode, that is, the amount of electricity at cathode Q _C, and the amount of electricity when it becomes an anode, ie, amount of electricity at the time of anode the ratio Q _C / Q _a and Q _a, for example, by in the range of 0.5 to 2.0, it is possible to produce a uniform honeycomb pits on the surface of the aluminum plate. If Q _C / Q _A is less than 0.50, non-uniform honeycomb pits are likely to be formed, and even if it exceeds 2.0, non-uniform honeycomb pits are likely to be formed. Q _C / Q _A is preferably in the range of 0.8 to 1.5.

  Examples of the alternating current waveform used for the electrochemical surface roughening treatment include a sine wave, a rectangular wave, a triangular wave, and a trapezoidal wave. Among these, a rectangular wave or a trapezoidal wave is preferable. In addition, the frequency of the alternating current is preferably 30 to 200 Hz, more preferably 40 to 120 Hz, from the viewpoint of the cost of manufacturing the power supply device. An example of a trapezoidal wave suitably used in the present invention is shown in FIG. In FIG. 1, the vertical axis indicates the current value, and the horizontal axis indicates time. Further, ta is the anode reaction time, tc is the cathode reaction time, tp is the time until the current value reaches the peak on the cathode cycle side from zero, and tp ′ is the time until the current value reaches the peak on the anode cycle side from zero. , Ia represents the peak current on the anode cycle side, and Ic represents the peak current on the cathode cycle side. When a trapezoidal wave is used as the waveform of the alternating current, the times tp and tp ′ until the current reaches a peak from zero are preferably 0.1 to 2 msec, and more preferably 0.3 to 1.5 msec. preferable. If tp and tp ′ are less than 0.1 msec, the impedance of the power supply circuit is affected, and a large power supply voltage is required at the rising of the current waveform, which may increase the equipment cost of the power supply. Moreover, when tp and tp 'exceed 2 msec, the influence of the trace component in acidic aqueous solution will become large, and it may become difficult to perform a uniform roughening process.

  Further, the duty of the alternating current used for the electrochemical surface roughening treatment is preferably in the range of 0.25 to 0.5 from the point of uniformly roughening the aluminum plate surface, 0.3 to More preferably, it is within the range of 0.4. The duty in the present invention refers to ta / T, where ta is the time during which the anode reaction of the aluminum plate continues in the period T of the alternating current (anode reaction time). In particular, on the surface of the aluminum plate during the cathode reaction, in addition to the formation of smut components mainly composed of aluminum hydroxide, dissolution and destruction of the oxide film occurred, and the start of the pitting reaction during the anode reaction of the next aluminum plate Therefore, the selection of the duty of the alternating current has a great effect on uniform roughening.

In the case of a trapezoidal wave or a rectangular wave, the alternating current current density is preferably such that the peak current density Iap on the anode cycle side and the peak current density Icp on the cathode cycle side are 10 to 200 A / dm ² , respectively. Icp / Iap is preferably in the range of 0.9 to 1.5. In electrochemical graining treatment, total amount of electricity used in the anode reaction of the aluminum plate at the time electrochemical graining treatment has been completed is preferably from 50~1000C / dm ^2. The electrochemical surface roughening treatment time is preferably 1 second to 30 minutes.

  As the acidic aqueous solution used for the electrochemical surface roughening treatment, those used for the electrochemical surface roughening treatment using a normal direct current or alternating current can be used, and among them, the acidic aqueous solution mainly composed of nitric acid. Alternatively, it is preferable to use an acidic aqueous solution mainly composed of hydrochloric acid. Here, “mainly” means that the main component is contained in the aqueous solution in an amount of 30% by mass or more, preferably 50% by mass or more based on the total components. Hereinafter, the same applies to other components.

  As the acidic aqueous solution mainly composed of nitric acid, as described above, those used for the electrochemical surface roughening treatment using a normal direct current or alternating current can be used. For example, one or more of nitric acid compounds such as aluminum nitrate, sodium nitrate and ammonium nitrate are added to a nitric acid aqueous solution having a nitric acid concentration of 5 to 15 g / L at a concentration from 0.01 g / L to saturation. be able to. In the acidic aqueous solution mainly composed of nitric acid, a metal contained in an aluminum alloy such as iron, copper, manganese, nickel, titanium, magnesium, or silicon may be dissolved.

  As the acidic aqueous solution mainly composed of nitric acid, nitric acid, aluminum salt, and nitrate are contained, and aluminum ion is 1 to 15 g / L, preferably 1 to 10 g / L, and ammonium ion is 10 to 300 ppm. Thus, it is preferable to use a solution obtained by adding aluminum nitrate and ammonium nitrate to an aqueous nitric acid solution having a nitric acid concentration of 5 to 15 g / L. The aluminum ions and ammonium ions increase spontaneously during the electrochemical surface roughening treatment. Moreover, it is preferable that the liquid temperature in this case is 10-95 degreeC, It is more preferable that it is 20-90 degreeC, It is especially preferable that it is 40-80 degreeC.

  In the electrochemical surface roughening treatment, a known electrolytic device such as a vertical type, a flat type, or a radial type can be used, but a radial type electrolytic device as described in JP-A-5-195300 is used. Particularly preferred. FIG. 2 is a schematic view of a radial type electrolyzer suitably used in the present invention. In FIG. 2, the radial electrolysis apparatus has an aluminum plate 11 wound around a radial drum roller 12 disposed in a main electrolytic cell 21 and electrolyzed by main poles 13 a and 13 b connected to an AC power source 20 in the course of conveyance. Is done. The acidic aqueous solution 14 is supplied from the solution supply port 15 through the slit 16 to the solution passage 17 between the radial drum roller 12 and the main poles 13a and 13b. Next, the aluminum plate 11 treated in the main electrolytic cell 21 is subjected to electrolytic treatment in the auxiliary anode cell 22. An auxiliary anode 18 is disposed opposite to the aluminum plate 11 in the auxiliary anode tank 22, and the acidic aqueous solution 14 is supplied so as to flow between the auxiliary anode 18 and the aluminum plate 11. Note that the current flowing through the auxiliary electrode is controlled by the thyristors 19a and 19b.

The main electrodes 13a and 13b can be selected from carbon, platinum, titanium, niobium, zirconium, stainless steel, electrodes used for cathodes for fuel cells, etc., and carbon is particularly preferable. As the carbon, commercially available impervious graphite for chemical devices, resin cored graphite, and the like can be used. The auxiliary anode 18 can be selected from known oxygen generating electrodes such as ferrite, iridium oxide, platinum, or platinum clad or plated with a valve metal such as titanium, niobium or zirconium.

  The supply direction of the acidic aqueous solution passing through the main electrolytic cell 21 and the auxiliary anode cell 22 may be parallel to the progress of the aluminum plate 11 or a counter. The relative flow rate of the acidic aqueous solution with respect to the aluminum plate is preferably 10 to 1000 cm / sec. One electrolysis apparatus can be connected to one or more AC power supplies. Two or more electrolysis devices may be used, and electrolysis conditions in each device may be the same or different. In addition, after the electrolytic treatment is completed, it is preferable to perform liquid drainage by a nip roller and water washing by spraying so that the treatment liquid is not taken out to the next process.

  In the case of using the above electrolyzer, for example, (i) the conductivity of the acid aqueous solution and (ii) the ultrasonic wave propagation velocity ( iii) Based on the nitric acid and aluminum ion concentrations determined from the temperature, add while adjusting the addition amount of nitric acid and water, and sequentially overflow the acidic aqueous solution with the same volume as the addition volume of nitric acid and water from the electrolyzer. It is preferable to keep the concentration of the acidic aqueous solution constant by discharging.

  Next, the surface treatments such as chemical etching treatment and desmut treatment in acidic aqueous solution or alkaline aqueous solution will be described in order. The surface treatment is performed before the electrochemical roughening treatment or after the electrochemical roughening treatment and before an anodic oxidation treatment described later. However, the description of each surface treatment below is an exemplification, and the present invention is not limited to the contents of each surface treatment below. In addition, the following treatments including the surface treatment are optionally performed.

<Alkaline etching treatment>
The alkali etching treatment is a treatment for chemically etching the surface of the aluminum plate in an alkaline aqueous solution, and is preferably performed before and after the electrochemical roughening treatment. Moreover, when performing a mechanical surface roughening process before an electrochemical surface roughening process, it is preferable to carry out after a mechanical surface roughening process. The alkali etching treatment is more advantageous than the acid etching treatment described later because the fine structure can be destroyed in a short time. Examples of the alkaline aqueous solution used for the alkali etching treatment include an aqueous solution containing one or more of caustic soda, sodium carbonate, sodium aluminate, sodium metasilicate, sodium phosphate, potassium hydroxide, lithium hydroxide and the like. . In particular, an aqueous solution mainly composed of sodium hydroxide (caustic soda) is preferable. The alkaline aqueous solution may contain 0.5 to 10% by mass of alloy components contained in the aluminum plate as well as aluminum. The concentration of the alkaline aqueous solution is preferably 1 to 50% by mass, and more preferably 1 to 30% by mass.

The alkaline etching treatment is preferably carried out by treating the alkaline aqueous solution at a temperature of 20 to 100 ° C., preferably 40 to 80 ° C., and treating for 1 to 120 seconds, preferably 2 to 60 seconds. Dissolution amount of aluminum, if carried out after mechanical graining treatment is preferably from 5 to 20 g / m ^2, if carried out after the electrochemical graining treatment is 0.01 to 20 g / m ² Preferably there is. When mixing a chemical etching solution in an alkaline aqueous solution first, it is preferable to prepare a treatment solution using liquid sodium hydroxide (caustic soda) and sodium aluminate (sodium aluminate). In addition, after the alkali etching process is completed, it is preferable to perform liquid drainage with a nip roller and water washing with a spray so that the processing liquid is not taken out to the next process.

  When the alkali etching treatment is performed after the electrochemical surface roughening treatment, smut generated by the electrochemical surface roughening treatment can be removed. As such an alkali etching treatment, for example, a method of contacting with 15 to 65 mass% sulfuric acid at a temperature of 50 to 90 ° C. as described in JP-A-53-12739 and JP-B-48-28123. A method for performing alkali etching described in Japanese Patent Publication No. JP-A-2000-133 is preferred.

<Acid etching process>
The acidic etching treatment is a treatment for chemically etching the aluminum plate in an acidic aqueous solution, and is preferably performed after the electrochemical surface roughening treatment. Moreover, when performing the said alkali etching process before and / or after the said electrochemical roughening process, it is also preferable to perform an acidic etching process after an alkali etching process. When the above-mentioned alkaline etching treatment is performed on the aluminum plate and then the above-mentioned acidic etching treatment is performed, the intermetallic compound containing silica or simple substance Si on the surface of the aluminum plate can be removed, and the anodic oxidation generated in the subsequent anodizing treatment Film defects can be eliminated. As a result, it is possible to prevent the trouble that the dot-like ink adheres to the non-image portion called “dirty stain” during printing.

  Examples of the acidic aqueous solution used for the acidic etching treatment include an aqueous solution containing phosphoric acid, nitric acid, sulfuric acid, chromic acid, hydrochloric acid, or a mixed acid of two or more of these. Of these, a sulfuric acid aqueous solution is preferable. The concentration of the acidic aqueous solution is preferably 50 to 500 g / L. The acidic aqueous solution may contain an alloy component contained in the aluminum plate as well as aluminum.

The acidic etching treatment is preferably performed by treating the liquid temperature at 60 to 90 ° C., preferably 70 to 80 ° C., for 1 to 10 seconds. The amount of dissolution of the aluminum plate at this time is preferably 0.001 to 0.2 g / m ² . The acid concentration, for example, the sulfuric acid concentration and the aluminum ion concentration are preferably selected from a range that does not crystallize at room temperature. A preferable aluminum ion concentration is 0.1 to 50 g / L, and particularly preferably 5 to 15 g / L. In addition, after the acidic etching process is completed, in order not to take out the processing liquid to the next process, it is preferable to perform liquid drainage by a nip roller and water washing by spraying.

<Desmut treatment>
When performing the alkali etching treatment before and / or after the electrochemical surface roughening treatment, smut is generally generated on the surface of the aluminum plate by the alkali etching treatment, so that phosphoric acid, nitric acid, sulfuric acid, chromic acid, The so-called desmut treatment, in which the smut is dissolved in an acidic solution containing hydrochloric acid, hydrofluoric acid, borofluoric acid, or a mixed acid of two or more of these, is preferably performed after the alkali etching treatment. In addition, after an alkali etching process, it is enough to perform any one of an acidic etching process and a desmut process.

  The concentration of the acidic solution is preferably 1 to 500 g / L. 0.001 to 50 g / L of the alloy component contained in the aluminum plate as well as aluminum may be dissolved in the acidic solution. The liquid temperature of the acidic solution is preferably 20 ° C to 95 ° C, more preferably 30 to 70 ° C. Moreover, it is preferable that processing time is 1-120 second, and it is more preferable that it is 2-60 second. Further, as the desmut treatment liquid (acid solution), it is preferable to use the waste liquid of the acidic aqueous solution used in the electrochemical surface roughening treatment in terms of reducing the amount of waste liquid. After the desmutting process is completed, it is preferable to perform liquid drainage by a nip roller and water washing by spraying so that the processing liquid is not taken out to the next process.

  As a combination of these surface treatments, preferred embodiments are shown below. First, a mechanical surface roughening treatment and / or an alkali etching treatment is performed, and then a desmut treatment is performed. Next, an electrochemical surface roughening process is performed, and then an acid etching process, an alkali etching process and a subsequent desmut process, an alkali etching process and a subsequent acidic etching process are performed.

<Anodizing treatment>
As described above, the anodizing treatment can be performed on the aluminum plate that has been subjected to the roughening treatment and, if necessary, other treatments. The anodizing treatment can be performed by a method conventionally used in this field. Specifically, when direct current or alternating current is applied to an aluminum plate in an aqueous solution or non-aqueous solution of sulfuric acid, phosphoric acid, chromic acid, oxalic acid, sulfamic acid, benzenesulfonic acid, etc., alone or in combination of two or more. An anodized film can be formed on the surface of the aluminum plate. The conditions for anodizing treatment vary depending on the electrolyte used, and thus cannot be determined in general. In general, the electrolyte concentration is 1 to 80% by mass, the solution temperature is 5 to 70 ° C., and the current density is 0.5. ˜60 A / dm ² , voltage 1 to 200 V, electrolysis time 1 to 1000 seconds are appropriate. Among these anodizing treatments, a method for anodizing at a high current density in a sulfuric acid electrolyte solution described in British Patent 1,412,768, and US Pat. No. 3,511,661. A method of anodizing treatment using phosphoric acid as an electrolytic bath is preferable. Further, multi-stage anodizing treatment such as anodizing treatment in sulfuric acid and further anodizing treatment in phosphoric acid can be performed.

In the present invention, the anodized film is preferably 1.0 g / m ² or more, more preferably 3.0 g / m ² or more, in terms of scratch resistance and printing durability. particularly preferably at .0g / m ² or more, in view that it requires a large amount of energy in order to provide a thicker coating is preferably at 100 g / m ² or less, 40 g / m ² or less More preferably, it is particularly preferably 20 g / m ² or less.

  On the surface of the anodized film, fine recesses called micropores are uniformly distributed. The density of the micropores present in the anodized film can be adjusted by appropriately selecting the treatment conditions.

<Pore wide processing>
In the present invention, for the purpose of lowering the thermal conductivity, it is preferable to perform a pore wide treatment for expanding the pore diameter of the micropore after the anodizing treatment. In this pore wide treatment, an aluminum substrate on which an anodized film is formed is immersed in an acid aqueous solution or an alkali aqueous solution to dissolve the anodized film and enlarge the pore diameter of the micropore. In the pore wide treatment, the dissolution amount of the anodized film is preferably 0.01 to 20 g / m ² , more preferably 0.1 to 5 g / m ² , and particularly preferably 0.2 to 4 g / m ^2. Done.

  When an aqueous acid solution is used for the pore wide treatment, it is preferable to use an aqueous solution of an inorganic acid such as sulfuric acid, phosphoric acid, nitric acid, hydrochloric acid, or a mixture thereof. The concentration of the acid aqueous solution is preferably 10 to 1000 g / L, and more preferably 20 to 500 g / L. The temperature of the acid aqueous solution is preferably 10 to 90 ° C, and more preferably 30 to 70 ° C. The immersion time in the acid aqueous solution is preferably 1 to 300 seconds, and more preferably 2 to 100 seconds. On the other hand, when an alkaline aqueous solution is used for pore wide treatment, it is preferable to use an aqueous solution of at least one alkali selected from the group consisting of sodium hydroxide, potassium hydroxide and lithium hydroxide. The pH of the alkaline aqueous solution is preferably 10 to 13, and more preferably 11.5 to 13.0. The temperature of the aqueous alkali solution is preferably 10 to 90 ° C, and more preferably 30 to 50 ° C. The immersion time in the alkaline aqueous solution is preferably 1 to 500 seconds, and more preferably 2 to 100 seconds. Further, the treatment with an acid aqueous solution may be performed after the alkali treatment.

<Treatment with an aqueous solution containing an inorganic fluorine compound and a silicate compound>
In this invention, after providing an anodic oxide film as mentioned above, it is good to process with the aqueous solution containing an inorganic fluorine compound and a silicate compound further. Thereby, when it is set as a lithographic printing plate, a support excellent in all of sensitivity, printing durability and stain resistance can be obtained. As the inorganic fluorine compound used in the present invention, a metal fluoride is preferably exemplified. Specifically, for example, sodium fluoride, potassium fluoride, calcium fluoride, magnesium fluoride, sodium hexafluorozirconium, hexafluorozirconium potassium, sodium hexafluorotitanate, potassium hexafluorotitanate, hexafluorozirconium hydrogen acid , Hexafluorotitanium hydrogen acid, hexafluorozirconium ammonium, ammonium hexafluorotitanate, hexafluorosilicic acid, nickel fluoride, iron fluoride, phosphorous phosphate, ammonium fluoride phosphate.

  Moreover, as a silicate compound used for this invention, a silicic acid and a silicate are mentioned, Among these, an alkali metal silicate is mentioned suitably. Specific examples include sodium silicate, potassium silicate, and lithium silicate. Of these, sodium silicate and potassium silicate are preferable. Examples of sodium silicate include No. 3 sodium silicate, No. 2 sodium silicate, No. 1 sodium silicate, sodium orthosilicate, sodium sesquisilicate, and sodium metasilicate. Examples of potassium silicate include No. 1 potassium silicate. Alternatively, an aluminosilicate containing aluminum or a borosilicate containing boron can be used. Examples of the silicic acid include orthosilicic acid, metasilicic acid, metadisilicic acid, metatrisilicic acid, and metatetrasilicic acid.

  The concentration of each compound in the aqueous solution is preferably 0.01% by mass or more, more preferably 0.05% by mass or more, in terms of the sealing of the anodized film for the inorganic fluorine compound, It is particularly preferably 0.1% by mass or more, and in terms of dirtiness, it is preferably 10% by mass or less, more preferably 1% by mass or less, and 0.5% by mass or less. Is particularly preferred. In addition, the silicic acid compound is preferably 0.01% by mass or more, more preferably 0.1% by mass or more, and particularly preferably 1% by mass or more in terms of dirtiness. Further, in terms of printing durability, the content is preferably 10% by mass or less, more preferably 7% by mass or less, and particularly preferably 5% by mass or less. Although the ratio with each compound in aqueous solution is not specifically limited, It is preferable that mass ratio of an inorganic fluorine compound and a silicic acid compound is 5: 95-95: 5, and it is 20: 80-80: 20. Is more preferable.

  Further, the aqueous solution containing the inorganic fluorine compound and the silicate compound may contain an appropriate amount of hydroxide such as sodium hydroxide, potassium hydroxide, or lithium hydroxide in order to increase the pH. Of these, sodium hydroxide and potassium hydroxide are preferable. Moreover, the aqueous solution containing an inorganic fluorine compound and a silicate compound may contain an alkaline earth metal salt or a Group 4 (Group IVB) metal salt. Examples of the alkaline earth metal salt include nitrates such as calcium nitrate, strontium nitrate, magnesium nitrate and barium nitrate; sulfates; hydrochlorides; phosphates; acetates; oxalates; Is mentioned. Examples of Group 4 (Group IVB) metal salts include titanium tetrachloride, titanium trichloride, potassium titanium fluoride, titanium oxalate potassium, titanium sulfate, titanium tetraiodide, zirconium chloride oxide, zirconium dioxide, zirconium oxychloride. And zirconium tetrachloride. These alkaline earth metal salts and Group 4 (Group IVB) metal salts are used alone or in combination of two or more.

The temperature of the aqueous solution is preferably 10 ° C or higher, more preferably 20 ° C or higher, preferably 100 ° C or lower, and more preferably 80 ° C or lower.
The aqueous solution preferably has a pH of 8 or more, more preferably has a pH of 10 or more, preferably has a pH of 13 or less, and more preferably has a pH of 12 or less.

  The method of treatment with an aqueous solution containing an inorganic fluorine compound and a silicate compound is not particularly limited, and examples thereof include a dipping method and a spray method. These may be used alone or in combination, or may be used in combination of two or more. Of these, the dipping method is preferred. When processing using the immersion method, the processing time is preferably 1 second or longer, more preferably 3 seconds or longer, more preferably 600 seconds or shorter, and 120 seconds or shorter. More preferred.

<Hydrophilic surface treatment>
In the present invention, the support of the present invention obtained by treatment with an aqueous solution containing an inorganic fluorine compound and a silicate compound as described above is further immersed in an aqueous solution containing one or more hydrophilic compounds. By doing so, it is preferable to perform a hydrophilic surface treatment. Preferred examples of the hydrophilic compound include polyvinyl phosphonic acid, a compound having a sulfonic acid group, a saccharide compound, and a silicate compound.

  The compound having a sulfonic acid group includes an aromatic sulfonic acid, a formaldehyde condensate thereof, a derivative thereof, and a salt thereof. Examples of the aromatic sulfonic acid include phenol sulfonic acid, catechol sulfonic acid, resorcinol sulfonic acid, benzene sulfonic acid, toluene sulfonic acid, lignin sulfonic acid, naphthalene sulfonic acid, acenaphthene-5-sulfonic acid, phenanthrene-2-sulfonic acid. Benzaldehyde-2 (or 3) -sulfonic acid, benzaldehyde-2,4 (or 3,5) -disulfonic acid, oxybenzylsulfonic acids, sulfobenzoic acid, sulfanilic acid, naphthionic acid, and taurine. Of these, benzenesulfonic acid, naphthalenesulfonic acid, and ligninsulfonic acid are preferable. Also preferred are formaldehyde condensates of benzene sulfonic acid, naphthalene sulfonic acid, and lignin sulfonic acid. Furthermore, these may be used as sulfonates. For example, sodium salt, potassium salt, lithium salt, calcium salt, magnesium salt can be mentioned. Of these, sodium salts and potassium salts are preferred. The pH of the aqueous solution containing the compound having a sulfonic acid group is preferably 4 to 6.5, and can be adjusted to the above pH range using sulfuric acid, sodium hydroxide, ammonia or the like.

  The saccharide compounds include monosaccharides and their sugar alcohols, oligosaccharides, polysaccharides, and glycosides. Monosaccharides and sugar alcohols thereof include, for example, trioses such as glycerol and sugar alcohols thereof; tetroses such as treose and erythritol and sugar alcohols thereof; pentoses such as arabinose and arabitol and sugar alcohols thereof; glucose, sorbitol and the like Hexoses and sugar alcohols thereof; heptoses and sugar alcohols such as D-glycero-D-galactoheptose and D-glycero-D-galactoheptitol; octoses such as D-erythro-D-galactoctitol and Examples thereof include sugar alcohols; nonoses such as D-erythro-L-gluco-nonulose and sugar alcohols thereof. Examples of oligosaccharides include disaccharides such as saccharose, trehalose, and lactose; and trisaccharides such as raffinose. Examples of the polysaccharide include amylose, arabinan, cyclodextrin, and cellulose alginate.

In the present invention, the “glycoside” refers to a compound in which a sugar moiety and a non-sugar moiety are bonded through an ether bond or the like. Glycosides can be classified by non-sugar moieties. For example, alkyl glycoside, phenol glycoside, coumarin glycoside, oxycoumarin glycoside, flavonoid glycoside, anthraquinone glycoside, triterpene glycoside, steroid glycoside, mustard oil glycoside Can be mentioned. Examples of the sugar moiety include the above-described monosaccharides and sugar alcohols thereof; oligosaccharides; polysaccharides. Among these, monosaccharides and oligosaccharides are preferable, and monosaccharides and disaccharides are more preferable. Examples of preferable glycosides include compounds represented by the following formula (I).

  In the above formula (I), R represents an alkyl group, an alkenyl group or an alkynyl group having a straight chain or a branched chain having 1 to 20 carbon atoms. Examples of the alkyl group having 1 to 20 carbon atoms include methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, undecyl, dodecyl, tridecyl, tetradecyl, pentadecyl, hexadecyl, heptadecyl, octadecyl, Nonadecyl and eicosyl groups may be mentioned, and these may be linear or branched, and may be cyclic alkyl groups. Examples of the alkenyl group having 1 to 20 carbon atoms include allyl and 2-butenyl groups, which may be linear or branched, and are cyclic alkenyl groups. May be. Examples of the alkynyl group having 1 to 20 carbon atoms include a 1-pentynyl group, which may be linear or branched, and may be a cyclic alkynyl group. Good.

  Specific examples of the compound represented by the above formula (I) include, for example, methyl glucoside, ethyl glucoside, propyl glucoside, isopropyl glucoside, butyl glucoside, isobutyl glucoside, n-hexyl glucoside, octyl glucoside, capryl glucoside, decyl glucoside, Examples include 2-ethylhexyl glucoside, 2-pentylnonyl glucoside, 2-hexyl decyl glucoside, lauryl glucoside, myristyl glucoside, stearyl glucoside, cyclohexyl glucoside, and 2-butynyl glucoside. These compounds are glucosides, which are a type of glycoside, in which the hemiacetal hydroxyl group of glucose is linked to other compounds in the form of an ether, and are obtained, for example, by a known method of reacting glucose with alcohols. be able to. Some of these alkyl glucosides are marketed under the trade name GLUCOPON by Henkel, Germany, and can be used in the present invention.

  Other examples of preferred glycosides include saponins, rutin trihydrate, hesperidin methyl chalcone, hesperidin, nalidine hydrate, phenol-β-D-glucopyranoside, salicin, 3 ′, 5,7-methoxy-7. -Rutinosides are mentioned.

  The pH of the aqueous solution containing the saccharide compound is preferably 8 to 11, and can be adjusted to the above pH range using potassium hydroxide, sulfuric acid, carbonic acid, sodium carbonate, phosphoric acid, sodium phosphate or the like.

  The concentration of the aqueous solution of polyvinylphosphonic acid is preferably 0.1 to 5% by mass, and more preferably 0.2 to 2.5%. The immersion temperature is preferably 10 to 70 ° C, and more preferably 30 to 60 ° C. The immersion time is preferably 1 to 20 seconds. Moreover, it is preferable that the density | concentration of the aqueous solution of the compound which has a sulfonic acid group is 0.02-0.2 mass%. The immersion temperature is preferably 60 to 100 ° C. The immersion time is preferably 1 to 300 seconds, and more preferably 10 to 100 seconds. Further, the aqueous solution of the saccharide compound preferably has a concentration of 0.5 to 10% by mass. The immersion temperature is preferably 40 to 70 ° C. The immersion time is preferably 2 to 300 seconds, and more preferably 5 to 30 seconds.

In the present invention, as the aqueous solution containing the hydrophilic compound, in addition to the organic compound aqueous solution as described above, an alkali metal silicate aqueous solution, potassium zirconium fluoride (K ₂ ZrF ₆ ) aqueous solution, phosphate / inorganic fluorine. An inorganic compound aqueous solution such as an aqueous solution containing the compound is also preferably used.

  The alkali metal silicate treatment is preferably an alkali metal silicate having a concentration of 0.01 to 30% by mass, more preferably 0.1 to 10% by mass, and a pH at 25 ° C. of preferably 10 to 13. It is carried out by immersing the support in an aqueous acid salt solution at 30 to 100 ° C., more preferably 50 to 90 ° C., preferably 0.5 to 40 seconds, more preferably 1 to 20 seconds.

  Examples of the alkali metal silicate used for the hydrophilic surface treatment include those listed as alkali metal silicates used in the aqueous solution containing the inorganic fluorine compound and the silicate compound described above. The aqueous solution of alkali metal silicate may contain an appropriate amount of a hydroxide such as sodium hydroxide, potassium hydroxide, or lithium hydroxide in order to increase the pH. Of these, sodium hydroxide and potassium hydroxide are preferable. The aqueous solution of alkali metal silicate may contain an alkaline earth metal salt or a Group 4 (Group IVB) metal salt. Examples of the alkaline earth metal salts include those listed as the alkaline earth metal salts that may be contained in the aqueous solution containing the inorganic fluorine compound and the silicate compound described above. Alkaline earth metal salts and Group 4 (Group IVB) metal salts are used alone or in combination of two or more.

  Zirconium potassium fluoride aqueous solution treatment is preferably carried out at an aqueous solution of potassium zirconium fluoride having a concentration of 0.1 to 10% by mass, more preferably 0.5 to 2% by mass, preferably at 30 to 80 ° C. It is preferably performed by dipping for 60 to 180 seconds.

  The phosphate / inorganic fluorine compound treatment is preferably an aqueous solution having a phosphate compound concentration of 5 to 20% by mass and an inorganic fluorine compound concentration of 0.01 to 1% by mass, preferably a pH of 3 to 5. The support is preferably immersed in at 20 to 100 ° C., more preferably at 40 to 80 ° C., preferably for 2 to 300 seconds, more preferably for 5 to 30 seconds.

  Examples of the phosphate used in the present invention include phosphates of metals such as alkali metals and alkaline earth metals. Specifically, for example, zinc phosphate, aluminum phosphate, ammonium phosphate, diammonium hydrogen phosphate, ammonium dihydrogen phosphate, monoammonium phosphate, monopotassium phosphate, monosodium phosphate, dihydrogen phosphate Potassium, dipotassium hydrogen phosphate, calcium phosphate, sodium ammonium hydrogen phosphate, magnesium hydrogen phosphate, magnesium phosphate, ferrous phosphate, ferric phosphate, sodium dihydrogen phosphate, sodium phosphate, hydrogen phosphate Disodium, lead phosphate, diammonium phosphate, calcium dihydrogen phosphate, lithium phosphate, phosphotungstic acid, ammonium phosphotungstate, sodium phosphotungstate, ammonium phosphomolybdate, sodium phosphomolybdate; sodium phosphite , Tripolyphosphate Potassium, and sodium pyrophosphate. Among these, sodium dihydrogen phosphate, disodium hydrogen phosphate, potassium dihydrogen phosphate, and dipotassium hydrogen phosphate are preferable.

Moreover, a metal fluoride is mentioned suitably as an inorganic fluorine compound used for hydrophilic surface treatment. Specific examples include those listed as inorganic fluorine compounds used in an aqueous solution containing the above-described inorganic fluorine compound and silicic acid compound.

  The aqueous solution used for the phosphate / inorganic fluorine compound treatment may contain one or more phosphates and inorganic fluorine compounds, respectively.

  After immersing the support in an aqueous solution containing these hydrophilic compounds, the support is washed with water or the like and dried.

  Due to the hydrophilic surface treatment described above, the sensitivity (improvement of printing durability in the case of a negative type photosensitive layer) improved by the pore-wide treatment after the anodizing treatment, and deterioration of the resistance to leaving stains (ink repellency) that occurs in exchange. The problem of printing smear is solved. That is, the phenomenon that the ink is difficult to remove when printing, particularly when the printing machine is stopped, and when the printing is restarted after the lithographic printing plate is left on the printing machine due to the enlargement of the pore diameter (residual stain resistance ( Although there is a problem that ink repellency (deterioration) is likely to occur, if the hydrophilic surface treatment is applied, the above problem is reduced.

The thus obtained support of the present invention preferably has a surface satisfying the following formula (1).
0.30 ≦ (A + B) / (A + B + C) ≦ 0.90 (1)
A: Peak area of fluorine (1S) obtained by measurement using X-ray photoelectron spectroscopy (counts · eV / sec)
B: Peak area of silicon (2P) obtained by measurement using X-ray photoelectron spectroscopy (counts · eV / sec)
C: Peak area of aluminum (2P) obtained by measurement using X-ray photoelectron spectroscopy (counts · eV / sec)

  In the above formula (1), “(A + B) / (A + B + C)” represents, for example, the degree of coating of the inorganic fluorine compound and silicic acid compound in the anodized film, and “(A + B) / (A + B + C)” The larger the value of “)”, the higher the coverage, and the smaller the value, the lower the coverage. Here, when the value of “(A + B) / (A + B + C)” is 0.30 or more, the effect of the treatment with the aqueous solution containing the inorganic fluorine compound and the silicate compound is increased, and the stain resistance (soil resistance) Properties and stain resistance). Therefore, the value of “(A + B) / (A + B + C)” is preferably 0.30 or more, and more preferably 0.40 or more. On the other hand, when the value of “(A + B) / (A + B + C)” is 0.90 or less, the effect of treatment with an aqueous solution containing an inorganic fluorine compound and a silicate compound becomes moderate, and the printing durability is more excellent It becomes. Therefore, the value of “(A + B) / (A + B + C)” is preferably 0.90 or less, and more preferably 0.70 or less.

<Undercoat layer>
In the present invention, before providing a writable recording layer by infrared laser exposure on the aluminum support thus obtained, if necessary, for example, a water-soluble metal salt such as zinc borate is used. An inorganic undercoat layer or an organic undercoat layer may be provided. As described above, the specific copolymer can be included in the undercoat layer.

Examples of the organic compound used in the organic undercoat layer include carboxymethyl cellulose; dextrin; gum arabic; polymers and copolymers having a sulfonic acid group in the side chain; polyacrylic acid; amino such as 2-aminoethylphosphonic acid Phosphonic acids having a group; organic phosphonic acids such as phenylphosphonic acid, naphthylphosphonic acid, alkylphosphonic acid, glycerophosphonic acid, methylenediphosphonic acid, and ethylenediphosphonic acid, which may have a substituent; Organic phosphoric acid such as phenylphosphonic acid, naphthylphosphoric acid, alkylphosphoric acid, glycerophosphoric acid, which may be substituted; phenylphosphinic acid, naphthylphosphinic acid, alkylphosphinic acid, glycerophosphinic acid, etc., which may have a substituent Organic phosphinic acids; amino acids such as glycine and β-alanine Amine hydrochloride having a hydroxyl group such as triethanolamine hydrochloride; and the yellow dye. These may be used alone or in combination of two or more.

The organic undercoat layer is provided by applying a solution obtained by dissolving the above organic compound in water or an organic solvent such as methanol, ethanol, methyl ethyl ketone, or a mixed solvent thereof on an aluminum plate and drying it. The concentration of the solution in which the organic compound is dissolved is preferably 0.005 to 10% by mass. The coating method is not particularly limited, and any method such as bar coater coating, spin coating, spray coating, curtain coating and the like can be used. The coating amount after drying of the organic undercoat layer is preferably ² to 200 mg / m ² , and more preferably 5 to 100 mg / m ² . When it is in the above range, the printing durability becomes better.

<Back coat layer>
The support obtained as described above has an organic polymer on the back surface (the surface on which the recording layer is not provided) so that the recording layer is not damaged even when it is stacked when the planographic printing plate precursor is used. A coating layer made of a compound (hereinafter also referred to as “backcoat layer”) may be provided as necessary. As a main component of the back coat layer, at least one resin selected from the group consisting of a saturated copolymerized polyester resin, a phenoxy resin, a polyvinyl acetal resin, and a vinylidene chloride copolymer resin having a glass transition point of 20 ° C. or higher is used. Is preferred.

  The saturated copolyester resin is composed of a dicarboxylic acid unit and a diol unit. Examples of the dicarboxylic acid unit include aromatic dicarboxylic acids such as phthalic acid, terephthalic acid, isophthalic acid, tetrabromophthalic acid, and tetrachlorophthalic acid; adipic acid, azelaic acid, succinic acid, oxalic acid, suberic acid, and sebacic acid , Saturated aliphatic dicarboxylic acids such as malonic acid and 1,4-cyclohexanedicarboxylic acid.

  The backcoat layer further comprises a dye or pigment for coloring, a silane coupling agent for improving the adhesion to the support, a diazo resin comprising a diazonium salt, an organic phosphonic acid, an organic phosphoric acid, a cationic polymer, Wax, higher fatty acids, higher fatty acid amides, silicone compounds composed of dimethylsiloxane, modified dimethylsiloxane, polyethylene powder and the like that are usually used as slipping agents can be appropriately contained.

  The thickness of the backcoat layer may basically be such that even if no interleaf is present, the recording layer to be described later is hardly damaged, and is preferably 0.01 to 8 μm. When the thickness is less than 0.01 μm, it is difficult to prevent the recording layer from being scratched when the planographic printing plate precursors are handled in layers. On the other hand, when the thickness exceeds 8 μm, the backcoat layer swells due to chemicals used around the lithographic printing plate during printing, the thickness varies, and the printing pressure may change to deteriorate the printing characteristics.

  Various methods can be used as a method of providing the back coat layer on the back surface of the support. For example, a method in which the above components for the back coat layer are dissolved in an appropriate solvent and applied as a solution, or an emulsified dispersion is applied and dried; a previously formed film is supported with an adhesive or heat. The method of bonding to a body; The method of forming a molten film with a melt extruder and bonding to a support body is mentioned. The most preferable method for securing a suitable thickness is a method in which the components for the backcoat layer are dissolved in a suitable solvent, applied as a solution, and dried. In this method, an organic solvent as described in JP-A-62-251739 can be used alone or in combination as a solvent.

  In the production of a lithographic printing plate precursor, either the back coat layer on the back surface or the recording layer on the front surface may be provided on the support first, or both may be provided simultaneously.

  Hereinafter, the support manufacturing apparatus used in the present invention will be described taking an aluminum plate as an example. The manufacturing process of the aluminum support used in the present invention is as follows: (1) An aluminum plate that has been rolled and wound in a coil shape is sent out from a feeding device composed of a multi-axis turret; Surface treatment, electrochemical roughening treatment, alkali etching treatment, acid etching treatment, desmut treatment, anodizing treatment, pore wide treatment (acid treatment or alkali treatment), sealing treatment, hydrophilic surface treatment, etc.) The aluminum plate is dried, and (3) the aluminum plate is wound into a coil by the winding device comprising the multi-axis turret, or the flatness of the aluminum plate is corrected, and then cut to a predetermined length. Are preferably accumulated. Further, if necessary, a step of forming an undercoat layer or a recording layer and drying it may be provided in the above process, and the planographic printing plate precursor may be wound into a coil by the winding device.

  Further, in the production of the aluminum support, a process of continuously inspecting the defects using an apparatus for inspecting defects on the surface of the aluminum plate, and attaching a mark label to the edge portion of the found defect portion is as follows: It is preferable to have more steps. Furthermore, in the production of the lithographic printing plate precursor according to the present invention, the aluminum plate in each of the above steps can be stopped even if the aluminum plate is stopped during the aluminum coil exchange process in the aluminum plate feeding step and the winding step. It is preferable to provide a reservoir device that keeps the traveling speed constant, and after the aluminum coil feeding step, it is preferable to provide a step of joining the aluminum plates by ultrasonic waves or arc welding.

  The apparatus used for manufacturing the aluminum support preferably has at least one apparatus for detecting the traveling position of the aluminum plate and correcting the traveling position, and for the purpose of cutting the tension of the aluminum plate and controlling the traveling speed. It is preferable to have at least one drive device and at least one dancer roll device for tension control. In addition, it is recorded whether or not the state of each process is a desired condition with a tracking device, and before the aluminum coil is wound, a label is attached to the edge of the aluminum web, and the condition after the label is the desired condition. It is also preferable to be able to determine later whether or not.

  In the present invention, the aluminum plate is preferably charged together with the interleaving paper and adsorbed to each other, and then cut and / or slit to a predetermined length. Also, based on the information on the label affixed to the edge part of the aluminum plate, after cutting to a predetermined length or before cutting, the non-defective part is separated from the defective part using the label as a mark. It is preferable to accumulate only

  In each process including the above-mentioned delivery process etc., it is important to set an optimum tension under each condition depending on the size (thickness and width) of the aluminum plate, the material of the aluminum, or the traveling speed of the aluminum web. Therefore, it is preferable to provide a plurality of tension control devices that feedback control signals from the tension sensing device using a drive device for tension cut and travel speed control and a dancer roll for tension control. Generally, the driving device uses a control method in which a DC motor and a main driving roller are combined. The main drive roller is made of general rubber, but in the process where the aluminum web is in a wet state, a roller made by laminating non-woven fabric can be used. Also, as each pass roller, rubber or metal is generally used, but in order to prevent this slip from occurring in a place where the slip is likely to occur with the aluminum web, a motor or a speed reducer is connected to each pass roller, It is also possible to provide an auxiliary drive device, such as controlling rotation at a constant speed by the above signal.

As described in JP-A-10-114046, the aluminum support used in the present invention has an arithmetic average roughness (R _a ) in the rolling direction as R ₁ and an arithmetic average roughness (R in the width direction). _a ) is R ₂ , R ₁ -R ₂ is preferably within 30% of R ₁ , and the average curvature in the rolling direction is 1.5 × 10 ⁻³ mm ⁻¹ or less, width The average curvature in the direction is preferably 1.5 × 10 ⁻³ mm ⁻¹ or less, and the average curvature in the direction perpendicular to the rolling direction is preferably 1.0 × 10 ⁻³ mm ⁻¹ or less. Moreover, it is preferable that the aluminum support manufactured by performing the roughening treatment or the like is corrected using a correction roll having a roll diameter of 20 to 80 mm and a rubber hardness of 50 to 95 degrees. Thereby, it is possible to supply a flatness aluminum coil-shaped base plate that does not cause exposure deviation of the lithographic printing plate precursor even in the automatic conveying process of the lithographic photosensitive printing machine. Japanese Patent Application Laid-Open No. 9-194093 discloses a web curl measuring method and apparatus, a curl correcting method and apparatus, and a web cutting apparatus, and these can also be used in the present invention.

  In addition, when continuously manufacturing an aluminum support, it is electrically monitored whether each process is operating under appropriate conditions, and a tracking device records whether the state of each process is a desired condition, Before the aluminum coil is wound, a label is attached to the edge of the aluminum web so that it can be determined later whether the desired condition is after the label. Can be judged.

  The aluminum plate processing apparatus used for the surface roughening treatment described above measures one or more of the temperature, specific gravity, electrical conductivity, and propagation speed of ultrasonic waves to determine the composition of the liquid, feedback control, and It is preferable that the liquid concentration is controlled to be constant by feedforward control. In the acidic aqueous solution in the processing apparatus, components contained in the aluminum plate such as aluminum ions are dissolved as the surface treatment of the aluminum plate proceeds. Therefore, in order to keep the aluminum ion concentration and the acid or alkali concentration constant, it is preferable to keep the liquid composition constant by intermittently adding water and acid or water and alkali. The concentration of the acid or alkali added here is preferably 10 to 98% by mass.

  In order to control the concentration of the acid or alkali, for example, the following method is preferable. First, a data table is created by measuring the conductivity, specific gravity, or ultrasonic wave propagation speed for each component liquid in a concentration range that is planned to be used in advance for each temperature. Then, the concentration is measured by referring to the data table of the non-measurement liquid in which the conductivity, specific gravity or ultrasonic wave propagation speed and temperature data of the liquid to be measured are created in advance. A method for measuring the propagation time of the ultrasonic wave with high accuracy and high stability is described in JP-A-6-235721. A concentration measurement system using the ultrasonic wave propagation speed is described in Japanese Patent Laid-Open No. 58-77656. Further, a method for preparing a data table showing a correlation between a plurality of physical quantity data for each liquid component and measuring the concentration of the multi-component liquid with reference to the data table is described in Japanese Patent Laid-Open No. Hei 4-19559. ing.

  When the concentration measurement method using the ultrasonic wave propagation velocity is combined with the conductivity and temperature values of the liquid to be measured and applied to the roughening process of the aluminum support, the process can be managed accurately in real time. Products of a certain quality can be manufactured, leading to an improvement in yield. In addition to the combination of temperature, ultrasonic wave propagation speed and conductivity, a data table is created for each concentration and temperature with physical quantities such as temperature and specific gravity, temperature and conductivity, temperature and conductivity and specific gravity, etc. If the method of measuring the concentration of the multi-component liquid with reference to the data table is applied to the roughening treatment step of the aluminum support, the same effect as described above can be obtained. In addition, by measuring the specific gravity and temperature and referring to a data table prepared in advance to obtain the slurry concentration of the object to be measured, the slurry concentration can be measured quickly and accurately.

Since the ultrasonic wave propagation velocity is easily affected by bubbles in the liquid, it is more preferable to perform the measurement in a pipe that is arranged vertically and has a flow velocity from below to above. The ultrasonic propagation velocity is preferably measured within a pressure range of 1 to 10 kg / cm ² in the pipe, and the frequency of the ultrasonic wave is preferably 0.5 to 3 MHz. In addition, the measurement of the specific gravity, electrical conductivity, and ultrasonic wave propagation velocity is easily affected by temperature, so it is necessary to measure in a pipe that is in a heat-retaining state and the temperature fluctuation is controlled within ± 0.3 ° C. preferable. Furthermore, since it is preferable to measure the electrical conductivity and specific gravity, or the electrical conductivity and the propagation speed of ultrasonic waves at the same temperature, it is particularly preferable to measure in the same pipe or the same pipe flow. The pressure fluctuation at the time of measurement leads to the fluctuation of temperature, so it is preferable that the pressure fluctuation is as low as possible. Further, it is preferable that the flow velocity distribution in the pipe to be measured is as small as possible. Furthermore, since the measurement is easily influenced by slurry, dust, and bubbles, it is preferable to measure a liquid that has passed through a filter, a deaerator, or the like.

[Plate making, printing]
In the planographic printing method of the present invention, the above-described planographic printing plate precursor of the present invention is exposed imagewise with an infrared laser.
Although the infrared laser used for this invention is not specifically limited, The solid laser and semiconductor laser which radiate | emit infrared rays with a wavelength of 760-1200 nm are mentioned suitably. The output of the infrared laser is preferably 100 mW or more. In order to shorten the exposure time, it is preferable to use a multi-beam laser device.
The exposure time per pixel is preferably within 20 μsec. Moreover, it is preferable that irradiation energy amount is 10-300 mJ / cm < ² >.

In the lithographic printing method of the present invention, as described above, after exposing the lithographic printing plate precursor of the present invention imagewise with an infrared laser, an oil-based ink and an aqueous component are supplied without any development processing steps. Print.
Specifically, after exposing the lithographic printing plate precursor with an infrared laser, mounting it on a printing machine without passing through the development process, printing the lithographic printing plate precursor on the printing machine, Examples include a method of printing with an infrared laser and printing without going through a development process.

After exposing the lithographic printing plate precursor imagewise with an infrared laser and supplying it with an aqueous component and oil-based ink without passing through a development process such as a wet development process, in the exposed part of the image recording layer, The image recording layer cured by exposure forms an oil-based ink receiving portion having an oleophilic surface. On the other hand, in the unexposed portion, the uncured image recording layer is dissolved or dispersed and removed by the supplied aqueous component and / or oil-based ink, and a hydrophilic surface is exposed in that portion.
As a result, the aqueous component adheres to the exposed hydrophilic surface, and the oil-based ink is deposited on the image recording layer in the exposed area, and printing is started. Here, the water-based component or the oil-based ink may be supplied to the printing plate first, but the oil-based ink is first used to prevent the water-based component from being contaminated by the image recording layer in the unexposed area. It is preferable to supply. As the aqueous component and the oil-based ink, a dampening water for normal lithographic printing and a printing ink are used.
In this way, the lithographic printing plate precursor is subjected to on-press development on an offset printing machine and used as it is for printing a large number of sheets.
〔Example〕

  Hereinafter, although an example and a comparative example explain the present invention in detail, the present invention is not limited to these.

1. Production of lithographic printing plate support (aluminum support) (support production example 1)
Aluminum plates used in Examples and Comparative Examples of the present invention were produced as follows from a molten aluminum alloy containing an alloy component of composition A shown in Table 1. First, a molten aluminum treatment including degassing and filtration was performed on the molten aluminum alloy, and an ingot having a thickness of 500 mm was produced by a DC casting method. After chamfering the surface of the obtained ingot by 10 mm, the ingot was heated, hot rolling was started at 400 ° C. without performing a soaking treatment, and rolling was performed until the plate thickness reached 4 mm. Next, after cold rolling to a thickness of 1.5 mm and intermediate annealing, it was finished again by cold rolling to 0.24 mm, flatness was corrected, and an aluminum plate was obtained.

  About the aluminum plate of the obtained composition A, surface treatment was performed in the procedure of (1)-(10) shown below. In addition, after each surface treatment and water washing, the liquid was removed with a nip roller. Water washing was performed by spraying water from a spray tube.

(1) Mechanical surface roughening treatment While supplying a suspension of silica sand having a specific gravity of 1.12 (abrasive, average particle size 25 μm) and water as a polishing slurry liquid to the surface of the aluminum plate by a spray tube, A mechanical roughening treatment was performed using a brush roller with a rotating nylon brush. The material of the nylon brush used was 6,10-nylon, the hair length was 50 mm, and the hair diameter was 0.48 mm. This nylon brush is formed by making a hole in a stainless steel tube of φ300 mm so as to be dense. Also, three nylon brushes were used for the brush roller, and the distance between the two support rollers (φ200 mm) provided at the lower part of the brush was 300 mm. The brush roller manages the load of the drive motor that rotates the brush with respect to the load before the nylon brush is pressed against the aluminum plate, and the average arithmetic roughness (R _a ) of the aluminum plate after roughening is 0. It was pressed down to 45 μm. The rotating direction of the brush was the same as the moving direction of the aluminum plate. Then, it washed with water. In addition, the concentration of the abrasive is referred to a table prepared in advance from the relationship between the abrasive concentration, temperature and specific gravity, the abrasive concentration is obtained from the temperature and specific gravity, water and abrasive are added by feedback control, The concentration of the abrasive was kept constant. Moreover, since the surface shape of the roughened aluminum plate changes when the abrasive is pulverized to reduce the particle size, the abrasive having a small particle size is sequentially discharged out of the system by the cyclone. The particle size of the abrasive was in the range of 1 to 35 μm.

(2) Alkali etching treatment An aqueous solution containing 70% by weight NaOH and 6.5% by weight aluminum ion at a liquid temperature of 70 ° C. was sprayed onto the aluminum plate with a spray tube to perform an alkali etching process. The amount of dissolution of the surface of the aluminum plate to be subjected to subsequent electrochemical roughening treatment was 8 g / m ² , and the amount of dissolution on the back surface was 2 g / m ² . The concentration of the etching solution used for the alkali etching treatment is determined in advance by referring to a table created from the relationship between the NaOH concentration, the aluminum ion concentration, the temperature, the specific gravity, and the conductivity of the solution. Then, the concentration of the etching solution was obtained and kept constant by adding water and a 48 mass% NaOH aqueous solution by feedback control. Then, it washed with water.

(3) Desmutting solution temperature A 35 ° C. nitric acid aqueous solution was sprayed onto an aluminum plate using a spray to perform desmutting treatment for 10 seconds. As the nitric acid aqueous solution, the overflow waste liquid from the electrolyzer used in the next step was used. Next, several spray tubes for spraying the desmut treatment liquid were installed so that the surface of the aluminum plate was not dried until the next step.

(4) Electrochemical surface roughening treatment An electrochemical surface roughening treatment was performed continuously using the trapezoidal wave alternating current shown in FIG. 1 and the electrolyzer 2 tank shown in FIG. As the acidic aqueous solution, a nitric acid aqueous solution containing 1% by mass of nitric acid (including 0.5% by mass of aluminum ions and 0.007% by mass of ammonium ions) was used. The liquid temperature was 50 ° C. The alternating current had a time tp and tp ′ of 1 msec from the current value reaching zero on the cathode cycle side and the anode cycle side, and the carbon electrode was the counter electrode. The current density at the peak of the alternating current is 50 A / dm ² for both the anode and the cathode of the aluminum plate, and the ratio of the amount of electricity (Q _C ) of the alternating current to the amount of electricity (Q _C ) at the time of cathode (Q _A ) Q _C / Q _A ) was 0.95, the duty ratio was 0.50, the frequency was 60 Hz, and the total amount of electricity at the time of anode was 180 _C / dm ² . Thereafter, washing with water was performed by spraying. Concentration control of nitric acid aqueous solution is done by adding 67% by mass of nitric acid stock solution and water in proportion to the amount of energization. And discharged outside the electrolyzer system. Along with this, referring to a table created in advance from the relationship between nitric acid concentration, aluminum ion concentration, temperature, liquid conductivity, and liquid ultrasonic propagation speed, the temperature, conductivity, and ultrasonic propagation speed of the aqueous nitric acid solution The concentration of the aqueous nitric acid solution was determined, and the concentration was kept constant by controlling the addition amount of the nitric acid stock solution and water sequentially.

(5) Alkali Etching Treatment An aqueous solution containing 45% by weight NaOH and 6.5% by weight aluminum ion at a liquid temperature of 45 ° C. was sprayed onto the aluminum plate using a spray to perform alkali etching treatment. The dissolution amount of the aluminum plate was 1 g / m ² . The concentration of the etching solution is determined in advance by referring to a table created from the relationship between the NaOH concentration, the aluminum ion concentration, the temperature, the specific gravity, and the conductivity of the solution. The concentration of the etching solution is obtained from the temperature, the specific gravity, and the conductivity. A 48% by weight aqueous NaOH solution was added to keep it constant. Then, it washed with water.

(6) Acidic etching treatment Acidic etching treatment was performed by using sulfuric acid (sulfuric acid concentration 300 g / L, aluminum ion concentration 15 g / L) as an acidic etching solution, and spraying this onto an aluminum plate at 80 ° C. for 7 seconds. The acid etchant concentration is determined by referring to a table created in advance from the relationship between sulfuric acid concentration, aluminum ion concentration, temperature, specific gravity, and liquid conductivity. Water and 50% by weight sulfuric acid were added under control to keep constant. Then, it washed with water.

(7) Anodizing treatment An aqueous solution (containing 0.5% by mass of aluminum ions) having an oxalic acid concentration of 50 g / L was used as an anodizing solution, a direct current voltage was used, a current density of 12 A / dm ² , a temperature of 50 ° C., Anodization of the aluminum plate was performed under the condition of 30 seconds to form an anodized film. As for the concentration of the anodizing solution, refer to the table created in advance from the relationship between the oxalic acid concentration, aluminum ion concentration, temperature, specific gravity, and liquid conductivity, obtain the liquid concentration from the temperature, specific gravity, and conductivity, and feed back Water and 50% by mass oxalic acid were added under control to keep constant. Thereafter, washing with water was performed by spraying.

(8) Pore wide treatment The aluminum plate after the anodic oxidation treatment was immersed in a pH 13 NaOH aqueous solution at 50 ° C. for 1 minute to perform pore wide treatment. Then, it washed with water.

(9) Treatment with an aqueous solution containing an inorganic fluorine compound and a silicate compound The aluminum plate after the pore-wide treatment was treated with sodium fluoride and No. 3 sodium silicate at concentrations of 0.1% by mass and 2.5% by mass, respectively. Then, using an aqueous solution prepared using pure water, the sample was immersed at 100 ° C. for 10 seconds. Then, it washed with water.

(10) Hydrophilic surface treatment No. 3 sodium silicate was treated with an aqueous solution having a concentration of 2.5% by mass at 70 ° C. for 12 seconds to carry out a hydrophilic surface treatment.
Thereafter, it was washed with water and dried to obtain an aluminum support 1.

(Support Production Examples 2-3)
(9) Except that the conditions in the treatment with the aqueous solution containing the inorganic fluorine compound and the silicate compound were changed as shown in Table 2, the same procedure as in Support Production Example 1 was followed. 3 was obtained.

(Comparative Example Support Production Example 1)
Support for Comparative Example 1 in the same manner as in Support Production Example 1 except that the following (R1) was performed instead of the treatment with the aqueous solution containing (9) inorganic fluorine compound and silicate compound. Got.
(R1) The aluminum plate after the Poi wide treatment was immersed for 10 seconds at 100 ° C. using an aqueous solution prepared by using No. 3 sodium silicate with pure water so that the concentration was 5.0% by mass. Then, it washed with water.

(Comparative Example Support Production Example 2)
Support for Comparative Example 2 in the same manner as in Support Production Example 1 except that the following (R2) was performed instead of the treatment with the aqueous solution containing (9) inorganic fluorine compound and silicate compound. Got.
(R2) The aluminum plate after the Poiwide treatment was immersed for 10 seconds at 50 ° C. using an aqueous solution prepared by using pure water so that the concentration of sodium fluoride was 0.1% by mass. Then, it washed with water.

2. Measurement by X-ray photoelectron spectroscopy The supports 1 to 3 and the supports 1 to 2 for comparative examples obtained above were subjected to X-ray photoelectron spectroscopy (ESCA, Electron Spectroscopic Chemical Analysis). The conditions of ESCA are shown below.
Apparatus: ESCA PHI-5400MC, ULVAC-PHI, Inc. X-ray source: Mg-Kα (400 W)
Pulse energy: 71.55 eV / 178.95 eV
take off angle: 45 degrees

  From the peak areas of the obtained fluorine (1S), silicon (2P) and aluminum (2P), the value of (A + B) / (A + B + C) in the above formula (1) was calculated. The results are shown in Table 2.

3. Preparation of planographic printing plate precursor (Example 1)
The specific example No. of the specific copolymer was added to the aluminum support 1 obtained above. 2 and a methanol solution of the copolymer (x / y = 80/20, mass average molecular weight 15000), and then oven-dried at 70 ° C. for 60 seconds to form an undercoat layer having a dry coating amount of 5 mg / m ^2. Formed.
Subsequently, an image recording layer coating solution (1) having the following composition was applied and dried in an oven at 70 ° C. for 60 seconds to obtain a lithographic printing plate precursor having a dry coating amount of 0.8 g / m ² .

Image recording layer coating solution (1)
・ Water 100g
・ The following microcapsule (1) (in terms of solid content) 5 g
-0.5 g of the following polymerization initiator (1)
・ 0.2 g of the following fluorosurfactant (1)

(Synthesis of microcapsule (1))
As an oil phase component, trimethylolpropane and xylene diisocyanate adduct (Mitsui Takeda Chemical Co., Ltd., Takenate D-110N) 10 g, pentaerythritol triacrylate (Nippon Kayaku Co., Ltd., SR444) 3.15 g, The following infrared absorber (1) 0.35 g and Pionein A-41C (manufactured by Takemoto Yushi Co., Ltd.) 0.1 g were dissolved in 17 g of ethyl acetate. As an aqueous phase component, 40 g of a 4% by mass aqueous solution of 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 became 20% by mass. All of the average particle diameters were 0.3 μm.

(Examples 2 to 10, Comparative Examples 1 to 4)
In Example 1, specific examples of the aluminum support 1 and the specific copolymer No. A lithographic printing plate precursor was obtained in the same manner as in Example 1 except that the compound represented by 2 was changed as shown in Table 3.

(Example 11)
On the aluminum support 1 prepared above, specific examples No. After applying a methanol solution of the compound represented by No. 43 (x / y = 80/20, weight average molecular weight 25000), it was oven-dried at 70 ° C. for 30 seconds to form an undercoat layer having a dry coating amount of 5 mg / m ^2. Formed.
Subsequently, an image recording layer coating solution (2) having the following composition was applied to the bar and then oven-dried at 100 ° C. for 60 seconds to form an image recording layer having a dry coating amount of 1.0 g / m ^2. An original plate was obtained.

Image recording layer coating solution (2)
・ The following infrared absorber (2) 0.05 g
・ 0.2 g of the above polymerization initiator (1)
・ The following binder polymer (1) 0.5 g
(Average molecular weight 80,000)
・ Polymerizable compound 1.0g
Isocyanuric acid EO-modified triacrylate (manufactured by Shin-Nakamura Chemical Co., Ltd., NK ester M-315)
・ 0.1 g of the above-mentioned fluorosurfactant (1)
・ Methyl ethyl ketone 18.0g

(Examples 12-20, Comparative Examples 5-8)
In Example 11, specific examples of the aluminum support 1 and the specific copolymer No. A lithographic printing plate precursor was obtained in the same manner as in Example 11 except that the compound represented by 43 was changed as shown in Table 4.

(Example 21)
An image recording layer coating solution (3) having the following composition is applied to the aluminum support 1 obtained as described above, and dried in an oven at 70 ° C. for 60 seconds to provide a lithographic printing with a dry coating amount of 0.8 g / m ² . I got the original version.

Image recording layer coating solution (3)
・ Water 100g
・ The above microcapsule (1) (in terms of solid content) 5 g
-Specific examples of specific copolymers No. A copolymer represented by 65 (x / y / z = 40/30/30, weight average molecular weight 9000) 0.06 g
・ 0.5 g of the above polymerization initiator (1)
・ 0.2 g of the above-mentioned fluorosurfactant (1)

(Example 22)
An image recording layer coating solution (4) having the following composition is bar-coated on the aluminum support 2 prepared above, and then oven-dried at 100 ° C. for 60 seconds to obtain an image recording with a dry coating amount of 1.0 g / m ² . A layer was formed to obtain an original plate for a lithographic printing plate.

Image recording layer coating solution (4)
・ 0.05 g of the above infrared absorber (2)
・ 0.2 g of the above polymerization initiator (1)
・ Binder polymer (1) 0.5g
(Average molecular weight 80,000)
・ Polymerizable compound 1.0g
Isocyanuric acid EO-modified triacrylate (manufactured by Shin-Nakamura Chemical Co., Ltd., NK ester M-315)
-Specific examples of specific copolymers No. 68 (x / y / z = 40/30/30, weight average molecular weight 9000) 0.025 g
・ 0.1 g of the above-mentioned fluorosurfactant (1)
・ Methyl ethyl ketone 18.0g

(Example 23)
On the support 2 prepared above, specific examples No. of specific copolymers are listed. After applying a methanol solution of the compound represented by No. 66 (x / y / z = 30/40/30, weight average molecular weight 15000), oven-dried at 70 ° C. for 30 seconds and under a dry coating amount of 5 mg / m ² A coating layer was formed.
Subsequently, an image recording layer coating solution (5) having the following composition was bar coated, followed by oven drying at 70 ° C. for 60 seconds to form an image recording layer having a dry coating amount of 0.8 g / m ^2. An original plate was obtained.

Image recording layer coating solution (5)
・ Water 40g
・ Propylene glycol monomethyl ether 50g
・ Methyl ethyl ketone 10g
・ The following infrared absorber (3) 0.15 g
・ The following lipophilic binder polymer (2) 0.5 g
(Average molecular weight 80,000)
・ The above microcapsule (1) (in terms of solid content) 5 g
・ 0.5 g of the above polymerization initiator (1)
・ 0.1 g of the above-mentioned fluorosurfactant (1)

4). Exposure and Printing The obtained lithographic printing plate precursor was exposed with a Trend setter 3244VX manufactured by Creo equipped with a water-cooled 40 W infrared semiconductor laser under the conditions of an output of 9 W, an outer drum rotating speed of 210 rpm, and a resolution of 2400 dpi. The exposure image includes a thin line chart. The exposed exposed original plate was attached to a cylinder of a printing machine SOR-M manufactured by Heidelberg without developing. Dampening solution (EU-3 (Etch solution manufactured by Fuji Photo Film Co., Ltd.) / Water / isopropyl alcohol = 1/89/10 (volume ratio)) and TRANS-G (N) black ink (Dainippon Ink and Chemicals, Inc.) After supplying dampening water and ink, 100 sheets were printed at a printing speed of 6000 sheets per hour.
When the on-press development of the unexposed part of the image recording layer was completed on the printing press and the number of printing papers required until the ink was not transferred to the printing paper was measured as on-press developability, Even when the planographic printing plate precursor was used, a printed matter having no stain on the non-image area was obtained within 100 sheets.

5). Evaluation In the above printing test, background stain, fine line reproducibility and printing durability were evaluated by the following methods. The respective results are shown in Table 5.
(1) Soil stain In the printing test, the water scale of the printing press was adjusted, and the soil stain was evaluated based on the water scale where the soil stain occurred. The case where the water scale where soiling occurs is less than 2, ◯, the case where it is 2 or more and 3 or less, Δ, the case where it is 3 or more and less than 4, Δ, or the case where it is 4 or more.

(2) Fine line reproducibility Generally, in the case of a negative lithographic printing plate precursor, when the exposure amount is small, the degree of cure of the image recording layer (photosensitive layer) is low, and when the amount of exposure is large, the degree of cure is high. When the image recording layer has a too low degree of curing, the printing durability of the lithographic printing plate becomes low, and the reproducibility of small dots and fine lines becomes poor. On the other hand, when the degree of cure of the image recording layer is high, the printing durability is high, and the reproducibility of small dots and fine lines is good.
In this example, as shown below, the negative lithographic printing plate precursor obtained as described above was evaluated for printing durability and fine line reproducibility under the same exposure amount conditions described above. It was used as an index of sensitivity. That is, it can be said that the sensitivity of the lithographic printing plate precursor is higher as the number of printed sheets in printing durability is higher and the fine line width in fine line reproducibility is thinner.

  As described above, after 100 sheets were printed and it was confirmed that a printed matter having no ink stains in the non-image area was obtained, 500 sheets were continuously printed. A thin line chart (10, 12, 14, 16, 18, 20, 25, 30, 35, 40, 60, 80, 100 and 200 μm fine line exposed charts) of a total of 600 printed sheets with a 25X magnifier The fine line reproducibility was evaluated by observing and the fine line width reproduced with ink without interruption. The results are shown in Table 5.

(3) Printing durability As described above, after printing was performed in the evaluation of fine line reproducibility, printing was further continued. As the number of printed sheets was increased, the image recording layer was gradually worn out and the ink acceptability was lowered, so that the ink density in the printing paper was lowered. Printing durability was evaluated by the number of printed sheets when the ink density (reflection density) was reduced by 0.1 from the start of printing. The results are shown in Table 5.

  From Table 5, it can be seen that the lithographic printing plate precursors (Examples 1 to 23) of the present invention are less likely to cause background stains and are excellent in on-press developability, fine line reproducibility and printing durability.

It is a wave form diagram which shows an example of the trapezoid wave used for the electrochemical roughening process using the alternating current used suitably for this invention. It is a side view which shows an example of the radial type cell in the electrochemical roughening process suitably used for this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 11 Aluminum plate 12 Radial drum roller 13a, 13b Main electrode 14 Acidic aqueous solution 15 Solution supply port 16 Slit 17 Solution path 18 Auxiliary anode 19a, 19b Thyristor 20 AC power source 21 Main electrolytic cell 22 Auxiliary anode cell

Claims (6)

A repeating unit having an image recording layer on a hydrophilic support whose surface satisfies the following formula (1), and containing at least one (a1) ethylenically unsaturated bond in the image recording layer or other layer; (A2) A lithographic printing plate precursor comprising a copolymer having a repeating unit containing at least one functional group that interacts with the support surface.
0.30 ≦ (A + B) / (A + B + C) ≦ 0.90 (1)
A: Peak area of fluorine (1S) obtained by measurement using X-ray photoelectron spectroscopy (counts · eV / sec)
B: Peak area of silicon (2P) obtained by measurement using X-ray photoelectron spectroscopy (counts · eV / sec)
C: Peak area of aluminum (2P) obtained by measurement using X-ray photoelectron spectroscopy (counts · eV / sec)   The lithographic printing plate precursor according to claim 1, wherein the copolymer is a copolymer having a hydrophilic portion.   The lithographic printing plate precursor according to claim 1 or 2, wherein the copolymer is contained in an undercoat layer provided between the hydrophilic support and the image recording layer. A repeating unit having an image recording layer on a hydrophilic support whose surface satisfies the following formula (1), and containing at least one (a1) ethylenically unsaturated bond in the image recording layer or other layer; (A2) A lithographic printing plate precursor comprising a copolymer having a repeating unit containing at least one functional group that interacts with the support surface is mounted on a printing press and imagewise exposed with an infrared laser. Alternatively, after imagewise exposure with an infrared laser, it is attached to a printing machine, and the lithographic printing plate precursor is supplied with printing ink and fountain solution to remove the infrared unexposed portion of the image recording layer, A planographic printing method for printing.
0.30 ≦ (A + B) / (A + B + C) ≦ 0.90 (1)
A: Peak area of fluorine (1S) obtained by measurement using X-ray photoelectron spectroscopy (counts · eV / sec)
B: Peak area of silicon (2P) obtained by measurement using X-ray photoelectron spectroscopy (counts · eV / sec)
C: Peak area of aluminum (2P) obtained by measurement using X-ray photoelectron spectroscopy (counts · eV / sec)   The lithographic printing method according to claim 4, wherein the copolymer is a copolymer having a hydrophilic portion.   The lithographic printing method according to claim 4 or 5, wherein the copolymer is contained in an undercoat layer provided between the hydrophilic support and the image recording layer.

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