JP2017136844A - Lithographic printing plate dummy plate, printing method using lithographic printing plate dummy plate, and, plate making method of lithographic printing plate dummy plate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a lithographic printing plate dummy plate, a printing method using the lithographic printing plate dummy plate and a plate making method of the lithographic printing plate dummy plate, which can prevent an edge from being contaminated and have excellent color sensor discernible aptitude.SOLUTION: A lithographic printing plate dummy plate which includes an aluminum support, a first hydrophilic layer formed directly on the aluminum support, and a second hydrophilic layer formed directly on the first hydrophilic layer in this order, in which at least one of the first hydrophilic layer and second hydrophilic layer contains a coloring agent having an absorption maximum in 350 to 800 nm, and the first hydrophilic layer contains a high-molecular compound having a support absorptive group and a hydrophilic group, a printing method that uses the lithographic printing plate dummy plate, and a plate making method of the lithographic printing plate dummy plate.SELECTED DRAWING: None

Description

  The present invention relates to a lithographic printing plate dummy plate, a printing method thereof, and a plate making method thereof.

In the field of multi-color printing, printing is performed by attaching dummy plates instead of printing plates to portions that do not require printing on the plate cylinder of a printing press. Such a dummy plate (sometimes referred to as a discard plate, a water plate, or a blank plate) includes a non-photosensitive layer and a hydrophilic layer containing a matting agent in this order on an aluminum support. (Patent Document 1) On the aluminum support, a non-photosensitive layer and a hydrophilic layer are included in this order, and a colorant having a maximum absorption at 350 to 550 nm is contained in the non-photosensitive layer. There has been known a discard plate (Patent Document 2) containing a matting agent in the hydrophilic layer.
Also, in consideration of the global environment, as a development method for lithographic printing plate precursors, a non-image area which is unnecessary on a printing machine at an early stage of the printing process without using a conventional wet processing using a developing solution. A so-called “on-press development” method has been put into practical use, and it is desired that a lithographic printing plate dummy plate can cope with such on-press development.

JP 2011-218778 A JP 2012-116165 A

However, when these dummy plates are used to continuously print on roll paper using a rotary press like newspaper printing, the end of the dummy plate is in the roll paper surface, so that it adheres to the end. It was necessary to further improve the linear stain (edge stain) in which the ink was transferred to the paper.
In addition, a plate used for printing (hereinafter referred to as the “main plate”) and a dummy plate need to be identified by a color sensor (hereinafter referred to as “color sensor identification aptitude”), but the above color sensor identification aptitude must be further improved.

  An object of the present invention is to provide a planographic printing plate dummy plate that is free from edge contamination and has excellent color sensor identification suitability, a printing method using a planographic printing plate dummy plate, and a method for making a planographic printing plate dummy plate Is to provide.

As a result of intensive studies to achieve the above-mentioned problems, the inventors have a first hydrophilic layer containing a specific polymer compound and a second hydrophilic layer in this order on the aluminum support, In addition, the dummy plate containing a colorant in at least one of the first hydrophilic layer and the second hydrophilic layer has been found to be excellent in color sensor identification suitability by preventing the occurrence of edge contamination. .
That is, it has been found that the above object can be achieved by the following configuration.

式中、Ｒ_１及びＲ_４は、各々独立に、水素原子又はメチル基を表す。Ｒ_２及びＲ_３は、各々独立に、水素原子、メチル基、又はエチル基を表す。Ｒ_５は、直鎖、分岐若しくは環状の炭素原子数２〜８の無置換アルキル基、置換基として芳香環基若しくは複素環基を有してもよい置換アルキル基、又は一般式（３）で表される置換基を表す。
一般式（３）において、Ｌは、炭素原子数２〜６のアルキレン基を表し、Ｒ_６は、直鎖、分岐若しくは環状の炭素原子数４〜８の無置換アルキル基、又は、置換基として芳香族基を有する置換アルキル基を表す。ｎはポリエーテルの平均付加モル数で２〜４の数である。
〔９〕
上記第２親水性層が、マット剤を含む、上記〔１〕〜〔８〕のいずれか１つに記載の平版印刷版ダミー版。
〔１０〕
上記マット剤が、親水性表面を有する有機樹脂マット剤である、上記〔９〕に記載の平版印刷版ダミー版。
〔１１〕
上記親水性表面が、シリカを含む、上記〔１０〕に記載の平版印刷版ダミー版。
〔１２〕
上記着色剤が、水溶性染料である、上記〔１〕〜〔１１〕のいずれか１つに記載の平版印刷版ダミー版。
〔１３〕
上記水溶性染料が、アゾ染料、フタロシアニン染料、アントラキノン染料、キサンテン染料、インディゴ染料、ピラニン染料、及び、スチルベン染料より選ばれる少なくも１つである、上記〔１２〕に記載の平版印刷版ダミー版。
〔１４〕
上記第２親水性層を、印刷インキ及び湿し水の少なくとも一方を供給して除去する機上現像処理工程を含む、上記〔１〕〜〔１３〕のいずれか１つに記載の平版印刷版ダミー版を用いた印刷方法。
〔１５〕
上記第２親水性層を、界面活性剤を含むｐＨ２〜１４の現像液により除去する溶液現像処理工程を含む、上記〔１〕〜〔１３〕のいずれか１つに記載の平版印刷版ダミー版の製版方法。 [1]
Lithographic printing having an aluminum support, a first hydrophilic layer directly formed on the aluminum support, and a second hydrophilic layer directly formed on the first hydrophilic layer in this order A dummy version,
At least one of the first hydrophilic layer and the second hydrophilic layer includes a colorant having an absorption maximum at 350 to 800 nm,
A lithographic printing plate dummy, wherein the first hydrophilic layer comprises a polymer compound having a support-adsorbing group and a hydrophilic group.
[2]
The lithographic printing plate dummy according to [1], wherein the first hydrophilic layer contains the colorant.
[3]
The polymer compound comprises a repeating unit having at least one group selected from the group consisting of a phosphonic acid group, a phosphoric acid group, a carboxylic acid group and a salt thereof as the support adsorbing group, and a sulfone as the hydrophilic group. The lithographic printing plate according to the above [1] or [2], which is a polymer compound having an acid group and a salt thereof, an amide group, and a repeating unit having at least one group or structure selected from the group consisting of betaine structures Dummy version.
[4]
The lithographic printing plate dummy according to any one of [1] to [3], wherein at least one of the first hydrophilic layer and the second hydrophilic layer contains a hydrophilic compound.
[5]
The lithographic printing plate dummy according to any one of [1] to [4], wherein at least one of the first hydrophilic layer and the second hydrophilic layer contains fine particles.
[6]
The lithographic printing plate dummy according to [5], wherein the fine particles are organic resin fine particles.
[7]
The lithographic printing plate dummy according to [5], wherein the fine particles are microgel.
[8]
The second hydrophilic layer, polyvinyl alcohol, carboxymethyl cellulose, and selected from a hydrophilic polymer having a repeating unit represented by the repeating unit represented by the following general formula represented by the following general formula (1) (2) The lithographic printing plate dummy plate according to any one of the above [1] to [7], comprising at least one of the above.

In the formula, R ₁ and R ₄ each independently represents a hydrogen atom or a methyl group. R ₂ and R ₃ each independently represents a hydrogen atom, a methyl group, or an ethyl group. R ₅ is a linear, branched or cyclic unsubstituted alkyl group having 2 to 8 carbon atoms, a substituted alkyl group which may have an aromatic ring group or a heterocyclic group as a substituent, or the general formula (3) Represents the substituent represented.
In the general formula (3), L represents an alkylene group having 2 to 6 carbon atoms, and R ₆ represents a linear, branched or cyclic unsubstituted alkyl group having 4 to 8 carbon atoms, or a substituent. A substituted alkyl group having an aromatic group is represented. n is an average added mole number of the polyether and is a number of 2 to 4.
[9]
The lithographic printing plate dummy according to any one of [1] to [8], wherein the second hydrophilic layer contains a matting agent.
[10]
The lithographic printing plate dummy according to [9] above, wherein the matting agent is an organic resin matting agent having a hydrophilic surface.
[11]
The lithographic printing plate dummy according to [10], wherein the hydrophilic surface contains silica.
[12]
The lithographic printing plate dummy according to any one of [1] to [11], wherein the colorant is a water-soluble dye.
[13]
The lithographic printing plate dummy according to [12], wherein the water-soluble dye is at least one selected from azo dyes, phthalocyanine dyes, anthraquinone dyes, xanthene dyes, indigo dyes, pyranine dyes, and stilbene dyes. .
[14]
The lithographic printing plate as described in any one of [1] to [13] above, comprising an on-press development process for removing the second hydrophilic layer by supplying at least one of printing ink and dampening water. Printing method using a dummy plate.
[15]
The lithographic printing plate dummy plate according to any one of the above [1] to [13], comprising a solution development treatment step of removing the second hydrophilic layer with a developer having a pH of 2 to 14 containing a surfactant. Plate making method.

  According to the present invention, the generation of edge stains is prevented and the lithographic printing plate dummy plate having excellent color sensor identification suitability, the printing method using the lithographic printing plate dummy plate, and the lithographic printing plate dummy plate making method Can be provided.

It is a schematic diagram which shows an example of the cross-sectional shape of the edge part of the cut lithographic printing plate dummy plate. It is a conceptual diagram which shows an example of the cutting part of a slitter apparatus. It is a side view which shows the concept of the process of the brush graining used for the mechanical roughening process in manufacture of the support body for lithographic printing plates. It is a side view which shows an example of the radial type cell in the electrochemical roughening process using alternating current in manufacture of the support body for lithographic printing plates. It is the schematic of the anodizing apparatus used for the anodizing process in manufacture of the support body for lithographic printing plates.

Hereinafter, the present invention will be described in detail.
The description of the constituent elements described below may be made based on typical embodiments of the present invention, but the present invention is not limited to such embodiments.
In the present specification, a numerical range expressed using “to” means a range including numerical values described before and after “to” as a lower limit value and an upper limit value.

[Aluminum support]
The lithographic printing plate dummy according to the present invention has an aluminum support. As the aluminum support of the lithographic printing plate dummy plate, a known aluminum support (including an aluminum alloy support) used for the lithographic printing plate precursor is used. Among these, an aluminum plate that has been roughened and anodized by a known method is preferably used.
As for the surface roughening treatment and the anodizing treatment, for example, an aluminum support for a lithographic printing plate precursor described in JP-A-2014-198453, paragraphs [0045]-[0064] and [0069]-[0077] A roughening treatment and anodizing treatment applied to the body can also be used.
For the aluminum plate, if necessary, the micropore enlargement treatment and sealing treatment of the anodized film described in JP-A-2001-253181 and JP-A-2001-322365, and US Pat. Alkali metal silicates or US patents as described in US Pat. Nos. 2,714,066, 3,181,461, 3,280,734 and 3,902,734 The surface hydrophilization treatment with polyvinylphosphonic acid or the like as described in each specification of 3,276,868, 4,153,461 and 4,689,272 is appropriately selected. It can be carried out.
The aluminum support preferably has a center line average roughness of 0.10 to 1.2 μm.

  If necessary, the aluminum support may have a back surface containing an organic polymer compound described in JP-A-5-45885 or a silicon alkoxy compound described in JP-A-6-35174. A coat layer can be provided.

[First hydrophilic layer and second hydrophilic layer]
The lithographic printing plate dummy according to the present invention has a first hydrophilic layer.
The first hydrophilic layer contains a polymer compound having a support adsorbing group and a hydrophilic group described later. Furthermore, you may have a coloring agent, microparticles | fine-particles, a hydrophilic compound, etc. which are mentioned later.
The first hydrophilic layer is formed directly on the aluminum support.
The first hydrophilic layer preferably does not contain, for example, a water-insoluble and alkali-soluble binder or a hydrophobic low molecular component contained in the non-photosensitive layer described in Patent Document 2. On-press developability is improved by not containing the water-insoluble and alkali-soluble binder or the hydrophobic low-molecular component.
The first hydrophilic layer is formed, for example, by applying an aqueous solution containing the above components onto an aluminum support.
Moreover, the lithographic printing plate dummy according to the present invention has a second hydrophilic layer on the first hydrophilic layer. Here, the second hydrophilic layer is formed directly on the first hydrophilic layer.
It is preferable that a 2nd hydrophilic layer contains the hydrophilic polymer mentioned later. Furthermore, you may have a coloring agent, a hydrophilic compound, the matting agent mentioned later, etc.
The second hydrophilic layer is a layer that can be removed in the on-press development processing step or the solution development processing step. Therefore, like the first hydrophilic layer described above, the second hydrophilic layer includes, for example, a water-insoluble and alkali-soluble binder contained in the non-photosensitive layer described in Patent Document 2, or a hydrophobic low-resistance layer. It is preferable not to contain a molecular component, and this can improve on-press developability.
The second hydrophilic layer is formed, for example, by applying an aqueous solution containing the above components on the first hydrophilic layer.
Hereinafter, components that each hydrophilic layer may contain will be described in detail.

<High molecular compound having a support adsorbing group and a hydrophilic group>
The first hydrophilic layer can improve edge contamination by including a polymer compound having a support-adsorbing group and a hydrophilic group.
Although the details are not clear, the present inventors presume as follows. That is, since the polymer compound contained in the first hydrophilic layer has a support-adsorbing group, the polymer compound is formed on the aluminum support in the on-machine development processing step or the solution development processing step. This is considered to be sufficiently retained and having a hydrophilic group to improve the hydrophilicity of the surface of the aluminum support and to suppress edge contamination.
Specific examples and preferred examples of the support-adsorbing group and specific examples and preferred examples of the hydrophilic group will be described later in the description of the repeating unit having each group.
The polymer compound preferably has a repeating unit having a support adsorptive group and a repeating unit having a hydrophilic group. Hereinafter, each repeating unit will be described in detail.

(Support adsorbing group)
The polymer compound preferably has a repeating unit having a support adsorptive group (a functional group that interacts with the support surface) in order to enhance the adhesion to the aluminum support.
Examples of the support-adsorptive group include an interaction such as an ionic bond, a hydrogen bond, and a polar interaction with a metal, a metal oxide, a hydroxyl group, etc. present on a support subjected to an anodizing treatment or a hydrophilic treatment. Possible groups are mentioned.
Specific examples of the support adsorptive group are given below.

In the formula, M ¹ and M ² each independently represent a hydrogen atom, a metal atom contained in an alkali metal or alkaline earth metal, or an ammonium group. From the viewpoint of soiling properties, the support-adsorbing group is preferably at least one group selected from the group consisting of phosphonic acid groups, phosphoric acid groups, carboxylic acid groups, and salts thereof. The support-adsorptive group is more preferably a phosphonic acid group or a salt thereof (structure 1), a phosphate ester group or a salt thereof (structure 2), a carboxylic acid group or a salt thereof, and a phosphate ester group or a salt thereof. Or a phosphonic acid group or a salt thereof. In the present invention, the repeating unit having a support adsorptive group is preferably represented by the following general formula (B1).

^Wherein, R a to R ^c each independently represent a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, or a halogen atom. Q represents a support-adsorptive group, and a preferred embodiment is the same as described above.
L is a single bond or a divalent linking group. A divalent linking group can be from 1 to 60 carbon atoms, 0 to 10 nitrogen atoms, 0 to 50 oxygen atoms, 1 to 100 hydrogen atoms, and 0 to It can be composed of up to 20 sulfur atoms, and more specifically, a combination of the following structural units.

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

  Although the specific example of the repeating unit which has a support body adsorptive group below is shown, this invention is not limited to these.

The polymer compound may have only one type of support adsorptive group or two or more types.
The content of the repeating unit having a support adsorptive group is preferably 2 to 80 mol%, more preferably 2 to 70 mol%, based on all repeating units of the polymer compound, It is more preferable that it is 50 mol%, and it is especially preferable that it is 10-40 mol%.

(Hydrophilic group)
The polymer compound preferably has a repeating unit having a hydrophilic group in order to increase the hydrophilicity of the aluminum support surface and suppress edge stains.
Specific examples of the hydrophilic group are given below.

In the above formula, M ¹ represents a hydrogen atom, a metal atom contained in an alkali metal or alkaline earth metal, or an ammonium group.
X ^{+ _{is, -N + R 1 R 2 -}} , - S + R 1 -, - I + -, - P + R 1 R 2 - is a group represented by.
R ₁ and R ₂ each independently represents a hydrogen atom, an alkyl group, an aryl group, an alkenyl group, or an alkynyl group, R ₃ represents an alkylene group, R ₄ represents an alkyl group, an aryl group, an alkenyl group, Or an alkynyl group is represented.
n represents an integer of 1 to 100. L is as defined above.

As the hydrophilic group, any functional group having high affinity with water can be suitably used. However, a sulfonic acid (salt) group, an amide group, a polyalkylene oxide group, a hydroxyl group, and a monosulfuric acid group can be used. An ester (salt) group, a sulfonamide group, an amino group, a sulfuric monoamide (salt) group, and a betaine structure are preferable, and a sulfonic acid (salt) group, an amide group, a polyalkylene oxide group, a hydroxyl group, and a betaine structure are more preferable.
The hydrophilic group is most preferably at least one group or structure selected from the group consisting of sulfonic acid groups and salts thereof, amide groups, and betaine structures.

  In the present invention, the repeating unit having a hydrophilic group is preferably represented by the following general formula (B2).

^Wherein, R a to R ^c each independently represent a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, or a halogen atom. L is as defined above. W represents a hydrophilic group, and a preferred embodiment is the same as described above.

  Specific examples of the repeating unit having a hydrophilic group used in the present invention are shown below, but the present invention is not limited thereto.

The polymer compound may have only one kind of hydrophilic group or two or more kinds.
The content of the repeating unit having a hydrophilic group is preferably from 30 to 98 mol%, more preferably from 40 to 90 mol%, more preferably from 50 to 90 mol, based on all repeating units of the polymer compound. % Is more preferable.

(Other repeat units)
The polymer compound may be a copolymer having a repeating unit other than the above (hereinafter, may be simply referred to as “other repeating unit”). Here, examples of other repeating units include repeating units derived from various known monomers.

The polymer compound includes, for example, a repeating unit corresponding to an alkyl (meth) acrylate or an (meth) acrylic acid aralkyl ester, in addition to a repeating unit having a support adsorptive group and a polymer unit having a hydrophilic group. It may have a repeating unit corresponding to meth) acrylamide or a derivative thereof, a repeating unit corresponding to α-hydroxymethyl acrylate, or a repeating unit corresponding to a styrene derivative.
The alkyl group of the (meth) acrylic acid alkyl ester is preferably an alkyl group having 1 to 5 carbon atoms and an alkyl group having 2 to 8 carbon atoms, and more preferably a methyl group. Examples of the substituent in the alkyl group having a substituent having 2 to 8 carbon atoms include a monovalent non-metallic atomic group excluding a hydrogen atom, and a halogen atom (-F, -Br, -Cl,- I), hydroxyl group, cyano group, alkoxy group, aryloxy group, mercapto group, alkylthio group, arylthio group, alkylcarbonyl group, arylcarbonyl group, carboxyl group and its conjugate base group, alkoxycarbonyl group, aryloxycarbonyl group, carbamoyl Group, aryl group, alkenyl group, alkynyl group and the like. Examples of the (meth) acrylic acid aralkyl ester include benzyl (meth) acrylate.
Examples of (meth) acrylamide derivatives include N-isopropylacrylamide, N-phenylmethacrylamide, N- (4-methoxycarbonylphenyl) methacrylamide, N, N-dimethylacrylamide, morpholinoacrylamide and the like.
Examples of the α-hydroxymethyl acrylate include ethyl α-hydroxymethyl acrylate and cyclohexyl α-hydroxymethyl acrylate.
Examples of styrene derivatives include styrene and 4-tertbutylstyrene.

  The content of other repeating units is preferably 40 mol% or less, more preferably 30 mol%, further preferably 20 mol% or less, based on all repeating units of the polymer compound. preferable.

  The polymer compound includes a repeating unit having at least one group selected from the group consisting of a phosphonic acid group, a phosphoric acid group, a carboxylic acid group and a salt thereof as the support adsorptive group, and a sulfone as the hydrophilic group. Particularly preferred is a polymer compound having an acid group and a salt thereof, an amide group, and a repeating unit having at least one group or structure selected from the group consisting of betaine structures.

  The content of the polymer compound having a support-adsorbing group and a hydrophilic group is preferably 50 to 100% by mass, and 60 to 95% by mass with respect to the total solid content of the first hydrophilic layer. More preferably, it is more preferably 65 to 90% by mass.

  The weight average molecular weight (Mw) of the polymer compound having a support-adsorbing group and a hydrophilic group can be arbitrarily set depending on the performance design of the planographic printing plate dummy plate. From the viewpoint of printing durability and stain resistance, the weight average molecular weight is preferably 2,000 to 1,000,000, more preferably 2,000 to 500,000, and 8,000 to 300,000. Most preferably.

<Colorant>
The lithographic printing plate dummy according to the present invention contains a colorant having an absorption maximum at 350 to 800 nm in at least one of the constituent layers (first hydrophilic layer and second hydrophilic layer). By including a colorant in the constituent layer, excellent discriminating ability by the setter color sensor can be imparted. That is, it is possible to make the color sensor identification appropriate.
The colorant may be contained in the first hydrophilic layer, in the second hydrophilic layer, or in both, but the colorant can be transferred to other members. From the viewpoint that it can be suppressed, it is more preferable that it is contained in the first hydrophilic layer, in other words, not contained in the second hydrophilic layer.

The colorant having an absorption maximum at 350 to 800 nm contained in the lithographic printing plate dummy according to the present invention is preferably a water-soluble dye. Examples of water-soluble dyes include anionic dyes and cationic dyes that are excellent in solubility in water.
Examples of water-soluble dyes include azo dyes, phthalocyanine dyes, anthraquinone dyes, xanthene dyes, indigo dyes, pyranine dyes, stilbene dyes, methine dyes, azomethine dyes, quinone dyes, triphenylmethane dyes, diphenylmethane dyes, naphthol dyes, tria dyes. Examples of the methane dye may include at least one selected from an azo dye, a phthalocyanine dye, an anthraquinone dye, a xanthene dye, an indigo dye, a pyranine dye, and a stilbene dye.
The color of the water-soluble dye is not particularly limited, but it is preferable that the color difference is large in order to distinguish between the lithographic printing plate precursor and the lithographic printing plate dummy plate by a setter color sensor. In consideration of the fact that the lithographic printing plate precursor is often colored blue, orange and yellow are preferred, and red is particularly preferred.

As the water-soluble dye, an anionic dye is more preferable. Among the anionic dyes, those having —SO ₃ X (X represents Li, Na or K) or —COOX (X represents Li, Na or K) as the hydrophilic group are preferable.
Examples of the anionic dye include [C. I. Acid Red] 1, 6, 8, 9, 13, 14, 18, 27, 35, 37, 52, 54, 57, 73, 82, 87, 88, 92, 97, 106, 111, 114, 118, 119 127, 131, 138, 143, 145, 151, 183, 195, 198, 211, 215, 217, 225, 226, 249, 251, 254, 256, 257, 260, 261, 265, 266, 274, 276 277, 289, 296, 299, 315, 318, 336, 337, 357, 359, 361, 362, 364, 366, 399, 407, 415, [C. I. Acid Orange] 56, [C. I. Acid Yellow] 1, 42, Edible Red No. 2, Edible Red No. 3, Edible Red No. 40, Edible Red No. 104, Edible Red No. 105, Edible Yellow No. 4 (Tartrazine), Edible Yellow No. 5 and the like.
As the azo dye, the disazo dye is more stable to light, heat, and acid than the monoazo dye, and the color change with time of the lithographic printing plate dummy plate is less, so that it is more preferable from the standpoint of discrimination by a color sensor.

  It is preferable that content of a coloring agent is 5-30 mass% with respect to the total solid of the structural layer (1st hydrophilic layer or 2nd hydrophilic layer) in which a coloring agent contains, 7-25 It is more preferable that it is mass%, and it is still more preferable that it is 10-20 mass%.

<Hydrophilic polymer>
The second hydrophilic layer preferably contains a hydrophilic polymer.
Examples of the hydrophilic polymer contained in the second hydrophilic layer include polyvinyl alcohol, modified polyvinyl alcohol, polyvinyl pyrrolidone, water-soluble cellulose derivatives, and poly (meth) acrylonitrile.
As the modified polyvinyl alcohol, acid-modified polyvinyl alcohol having a carboxy group or a sulfo group is preferably used. Specific examples include modified polyvinyl alcohols described in JP-A-2005-250216 and JP-A-2006-259137.
The hydrophilic polymer contained in the second hydrophilic layer may be used alone or in combination of two or more.

  The second hydrophilic layer may also contain a compound having a repeating unit represented by the following general formula (1) and a repeating unit represented by the following general formula (2) as a hydrophilic polymer. preferable.

In the formula, R ₁ and R ₄ each independently represents a hydrogen atom or a methyl group. R ₂ and R ₃ each independently represents a hydrogen atom, a methyl group, or an ethyl group. R ₅ is a linear, branched or cyclic unsubstituted alkyl group having 2 to 8 carbon atoms, a substituted alkyl group which may have an aromatic ring group or a heterocyclic group as a substituent, or the general formula (3) Represents the substituent represented.
In the general formula (3), L represents an alkylene group having 2 to 6 carbon atoms, and R ₆ represents a linear, branched or cyclic unsubstituted alkyl group having 4 to 8 carbon atoms, or a substituent. A substituted alkyl group having an aromatic group is represented. n is an average added mole number of the polyether and is a number of 2 to 4.

As a combination of the repeating units represented by the general formula (1) and the general formula (2), R ₁ and R _{4 in} the general formula (1) and the general formula (2) are both hydrogen atoms, the general formula (1 Most preferred is a combination in which R ₂ and R ₃ are both hydrogen atoms and R _{5 in the} general formula (2) is a branched and unsubstituted alkyl group having 3 to 4 carbon atoms.

  Specific examples of those derived from the repeating unit represented by the general formula (1) include acrylamide, methacrylamide, N-methylacrylamide, N-methylmethacrylamide, N-ethylacrylamide, N-ethylmethacrylamide, N, N. -Dimethylacrylamide, N, N-dimethylmethacrylamide, N, N-diethylacrylamide, N, N-diethylmethacrylamide, N, N-ethylmethylacrylamide, N, N-ethylmethylmethacrylamide.

  Specific examples of those derived from the repeating unit represented by the general formula (2) include ethyl acrylate, propyl acrylate, isopropyl acrylate, n-butyl acrylate, i-butyl acrylate, t-butyl acrylate, Pentyl acrylate, hexyl acrylate, cyclohexyl acrylate, heptyl acrylate, octyl acrylate, 2-ethylhexyl acrylate, ethyl methacrylate, propyl methacrylate, isopropyl methacrylate, n-butyl methacrylate, i-butyl methacrylate, Examples thereof include t-butyl methacrylate, pentyl methacrylate, hexyl methacrylate, cyclohexyl methacrylate, heptyl methacrylate, octyl methacrylate, and 2-ethylhexyl methacrylate.

  As a compound which has the said repeating unit, 70-95 mol% of repeating units represented by General formula (1) and 5-30 mol% of repeating units represented by General formula (2) are included with respect to all the repeating units. More preferred are those containing 70 to 80 mol% of the repeating unit represented by the general formula (1) and more preferably 20 to 30 mol% of the repeating unit represented by the general formula (2). Most preferred are those containing 75 to 80 mol% of repeating units and 20 to 25 mol% of repeating units represented by the general formula (2).

  It is preferable that the compound having the repeating unit further has a repeating unit represented by the following general formula (4) in an amount of 0.3 to 5.0 mol% based on all repeating units.

In the formula, R ₇ represents a hydrogen atom or a methyl group. X is represented by a single bond, a structure represented by the general formula (5), or a structure having a combination thereof. Y is a carboxylic acid group, a carboxylic acid group, a sulfonic acid group, a sulfonic acid group, a phosphoric acid group, a phosphoric acid group, a phosphonic acid group, a phosphonic acid group, a hydroxyl group, a carbobetaine group, a sulfobetaine group, and an ammonium group. Represents at least one substituent selected from:

  The weight average molecular weight (Mw) of the compound having a repeating unit is preferably 10,000 to 200,000, more preferably 10,000 to 100,000, and most preferably 10,000 to 30,000.

  Specific examples of the compounds having the above repeating units are shown in Tables 1 to 9 below. The numbers in the table represent compound numbers.

  The content of the hydrophilic polymer is preferably 40% by mass or more, more preferably 60% by mass or more, and further preferably 80% by mass or more based on the solid content of the second hydrophilic layer. preferable.

<Polysaccharides>
The second hydrophilic layer can contain a polysaccharide. Examples of polysaccharides include starch derivatives (eg, dextrin, enzymatically degraded dextrin, hydroxypropylated starch, carboxymethylated starch, phosphate esterified starch, polyoxyalkylene grafted starch, cyclodextrin), celluloses (eg, carboxymethylcellulose, carboxy Ethyl cellulose, methyl cellulose, hydroxypropyl cellulose, methylpropyl cellulose, etc.), carrageenan, alginic acid, guar gum, locust bean gum, xanthan gum, gum arabic, soybean polysaccharide and the like.
Among them, dextrin, starch derivatives such as polyoxyalkylene grafted starch, gum arabic, carboxymethyl cellulose, soybean polysaccharide and the like are preferably used.
The polysaccharide is preferably used in the range of 1 to 20% by mass with respect to the solid content of the second hydrophilic layer.
Furthermore, the second hydrophilic layer is used to protect ordinary lithographic printing plate precursors such as a plasticizer for imparting flexibility, a surfactant for improving coatability, and inorganic fine particles for controlling surface slipperiness. Can contain known additives used in the layer

  The second hydrophilic layer is at least one selected from polyvinyl alcohol, carboxymethylcellulose, and a compound having a repeating unit represented by the general formula (1) and a repeating unit represented by the general formula (2). It is preferable to contain.

<Matting agent>
The second hydrophilic layer may contain a matting agent. Thereby, the conveyance property (setter conveyance property) by the setter of the planographic printing plate dummy plate can be made excellent. The basic characteristics desired for such particles that act as a matting agent are that the transmission of light used for exposure is not substantially inhibited, and it does not soften or become sticky depending on the humidity and temperature in the air. A resin that is added to the second hydrophilic layer to impart appropriate irregularities to the surface and reduces the contact area is preferable.
From the viewpoint of suppressing scratching, it is preferable that the matting agent can relieve the stress generated when it is rubbed with the hard aluminum support surface. Furthermore, the matting agent is a hydrophilic polymer that serves as a binder for the second hydrophilic layer, and preferably has a high affinity with general-purpose polyvinyl alcohol in the hydrophilic layer and is well kneaded in the film. Those which are difficult to be detached from the film surface are preferred.
As the matting agent, any known matting agent can be used as long as it satisfies the basic characteristics, and is not limited. However, in the present invention, an organic resin matting agent having a hydrophilic surface is preferable. In the organic resin matting agent, the hydrophilic surface preferably contains silica. The organic resin matting agent having a hydrophilic surface containing silica is preferably silica-coated organic resin particles whose surface is coated with silica.

(Silica-coated organic resin particles)
Silica-coated organic resin particles are obtained by surface-coating particles made of an organic resin with silica. Silica-coated organic resin particles are used for adhesion between the surface of the second hydrophilic layer of the planographic printing plate dummy plate and the back surface of the adjacent aluminum support of the planographic printing plate dummy plate, and the surface of the second hydrophilic layer and the aluminum support. This is preferable in order to suppress rubbing scratches generated between the back surface and the back surface.

  As the organic resin constituting the organic resin particles serving as the core of the silica-coated organic resin particles, any resin having the above-described physical properties can be used without limitation. For example, polyacrylic acid resin, polyurethane Resin, polystyrene resin, polyester resin, epoxy resin, phenol resin, melamine resin, silicone resin and the like. Among these, from the viewpoint of affinity with polyvinyl alcohol, which is a preferred hydrophilic polymer, polyacrylic acid resins, polyurethane resins, melamine resins, and the like are preferable.

  The material for forming the silica layer covering the surface of the organic resin particles is preferably a compound having an alkoxysilyl group such as a condensate of an alkoxysiloxane compound, particularly a siloxane material used in a sol-gel method. Preferred examples include silica particles such as silica sol, colloidal silica, and silica nanoparticles.

The structure of the silica-coated organic resin particles is that even if the silica particles adhere to the surface of the organic resin particles as a solid component, the alkoxysiloxane compound is subjected to a condensation reaction to form a siloxane compound layer on the surface of the organic resin particles. It may be formed.
Silica does not necessarily have to cover the entire surface of the organic resin particles, and the effect of the present invention can be obtained if the surface is coated in an amount of 0.5% by weight or more with respect to at least the organic resin particles. That is, the presence of silica on at least a part of the surface of the organic resin particles achieves an improved affinity with hydrophilic polymers such as polyvinyl alcohol on the surface of the organic particles, and the matting agent is removed even when subjected to external stress. Is suppressed, and excellent scratch resistance and adhesion resistance can be maintained.
Moreover, the silica layer which coat | covers the organic resin particle surface may be further coat | covered with organic resin in the range which does not impair the effect of this invention.
The surface coating state of silica can be confirmed by morphological observation with a transmission electron microscope (TEM) or the like, and the silica coating amount is detected by detecting Si atoms by elemental analysis such as fluorescent X-ray analysis. This can be confirmed by calculating the amount of silica present.

  There is no particular limitation on the method for producing the silica-coated organic resin particles, and the silica surface coating layer is formed simultaneously with the formation of the organic resin particles by coexisting the silica particles or the silica precursor compound with the monomer component as the raw material of the organic resin particles. The method may be a method, or after forming the organic resin particles, the silica particles may be physically attached to the surface and then fixed.

To give an example of the production method, first, in water containing a water-soluble polymer such as polyvinyl alcohol, methylcellulose, polyacrylic acid, and a suspension stabilizer appropriately selected from inorganic suspensions such as calcium phosphate and calcium carbonate. Silica and raw material resin (more specifically, a monomer capable of suspension polymerization, a prepolymer capable of suspension crosslinking, or a raw material resin such as a resin liquid constituting the organic resin described above), Addition, stirring, and mixing to prepare a suspension in which silica and raw resin are dispersed. At that time, an emulsion (suspension) having a target particle diameter can be formed by adjusting the type of suspension stabilizer, its concentration, the rotational speed of stirring, and the like. Next, the suspension is heated to start the reaction, and resin particles are produced by suspension polymerization or suspension crosslinking of the resin raw material. At this time, the coexisting silica is fixed to the resin particles that are cured by polymerization or a crosslinking reaction, particularly in the vicinity of the resin particle surface due to the physical properties thereof. Thereafter, this is subjected to solid-liquid separation, and the suspension stabilizer attached to the particles is removed by washing, followed by drying. Thereby, substantially spherical organic resin particles having a desired particle diameter on which silica is immobilized are obtained.
In this way, it is possible to obtain a resin of a desired size by controlling the conditions during suspension polymerization or suspension crosslinking, but it is possible to produce silica-attached organic resin particles without strictly performing such control. Then, silica-coated particles having a desired size can be obtained by a mesh filtration method.

  When the total amount of the raw material resin and silica is 100 parts, the suspension stabilizer 0 is first added to 200 to 800 parts of water as a dispersion medium when the total amount of the raw material resin and silica is 100 parts. Add 1 to 20 parts, and dissolve or disperse sufficiently. Into the liquid, add a mixture of 100 parts of the raw material resin and silica, and stir the stirring speed so that the dispersed particles have a predetermined particle size. The mixture is stirred while adjusting, and after adjusting the particle size, the liquid temperature is raised to 30 to 90 ° C. and reacted for 1 to 8 hours.

  Regarding the method for producing silica-coated particles, the above-described method is an example. For example, JP-A No. 2002-327036, JP-A No. 2002-173410, JP-A No. 2004-307837, and JP-A No. 2006 are disclosed. The silica-coated organic resin particles described in detail in Japanese Patent No. 38246 and obtained by the method described herein can be suitably used in the present invention.

  Silica-coated organic resin particles are also available as commercial products. Specific examples of the silica / melamine composite particles include OPTBEADS 2000M, OPTBEADS 3500M, OPTBEADS 6500M, OPTBEADS 6500M, manufactured by Nissan Chemical Industries, Ltd. Examples include beads 10500M, opto beads 3500S, and opto beads 6500S. As silica / acrylic composite particles, Art Pearl G-200 transparent, Art Pearl G-400 transparent, Art Pearl G-800 transparent, Art Pearl GR-400 transparent, Art Pearl GR-600 transparent manufactured by Negami Kogyo Co., Ltd., Art Pearl GR-800 transparent, art pearl J-7P can be mentioned. As silica / urethane composite particles, Art Pearl C-400 transparent, C-800 transparent, P-800T, U-600T, U-800T, CF-600T, CF800T, manufactured by Negami Kogyo Co., Ltd., Daiichi Seika Co., Ltd. Examples thereof include dynamic beads CN5070D and dampula coat THU.

The shape of the silica-coated organic resin particles is preferably a true spherical shape, but may be a so-called spindle shape having a flat plate shape or an elliptical projection.
A preferable weight average particle diameter is 1 to 30 μmφ, more preferably 1.5 to 20 μmφ, and further preferably 2 to 15 μmφ. In this range, a sufficient spacer function and mat performance can be expressed, the immobilization to the hydrophilic layer surface is easy, and it has an excellent holding function against contact stress from the outside.

Distribution of the matting agent in the second hydrophilic layer is preferably 5~1,000mg / ^{m 2,} more preferably 10 to 500 mg / ^{m 2,} more preferably 20 to 200 mg / ^{m 2.}
The addition amount of the matting agent with respect to the entire second hydrophilic layer is preferably 0.5 to 95% by weight, more preferably 1 to 50% by weight, and more preferably 2 to 20% by weight based on the total solid content of the second hydrophilic layer. % Is more preferable.

  In addition to the silica-coated organic resin particles, other organic resin particles (without the silica coating layer) can be used in combination with the second hydrophilic layer as long as the effects of the present invention are not impaired. Examples of the organic resin particles that can be used in combination include those described in paragraphs 0029 to 0032 of Japanese Patent No. 4213756. Further, silicon dioxide, aluminum oxide and the like described in paragraphs 0022 to 0024 of Japanese Patent No. 3329657 may be added to the second hydrophilic layer as long as the effects of the present invention are not impaired.

<Inorganic layered compound>
The second hydrophilic layer may contain an inorganic layered compound such as natural mica and synthetic mica as described in JP-A-2005-119273 for suppressing scratches.

<Fine particles>
Further, at least one of the first hydrophilic layer and the second hydrophilic layer may contain fine particles. Here, the fine particles may constitute the matting agent that may be contained in the second hydrophilic layer, or the other organic resin particles that may be used in combination with the matting agent. The fine particles may be either organic fine particles or inorganic fine particles. When the lithographic printing plate dummy plate is subjected to on-press development due to the presence of fine particles, it is considered that the edge stain is eliminated by improving the permeability of the fountain solution and promoting the on-press development.

[Organic fine particles]
Among the fine particles, organic resin fine particles such as microgel (crosslinked polymer fine particles) and thermoplastic fine particles are preferably used as the organic fine particles.

(Microgel)
A microgel is a reactive or non-reactive resin particle dispersed in an aqueous medium. The microgel may be in the form of a reactive microgel by having a polymerizable group in the particle surface or on the particle surface, preferably on the particle surface.

  The resin constituting the particles is preferably polyurea, polyurethane, polyester, polycarbonate, polyamide, or a mixture thereof, more preferably polyurea or polyurethane, and particularly preferably polyurethane.

  The microgel can be prepared by a known method. For example, a monohydric alcohol having an ethylenically unsaturated group is reacted with an adduct of a polyhydric alcohol and a diisocyanate, and dissolved in ethyl acetate together with a small amount of a surfactant to prepare an oily component. As an aqueous component, an aqueous solution of polyvinyl alcohol is prepared. An oily component and an aqueous component are mixed, and the mixture is emulsified and dispersed by high-speed stirring with a mechanical stirrer, and the solid content concentration is adjusted to obtain a microgel.

(Thermoplastic fine particles)
Examples of the thermoplastic fine particles include Research Disclosure No. 1 of January 1992. 33303, JP-A-9-123387, JP-A-9-131850, JP-A-9-171249, JP-A-9-171250, European Patent No. 931647, and the like can be preferably exemplified. .

  Specific examples of the polymer constituting the thermoplastic fine particles include ethylene, styrene, vinyl chloride, methyl acrylate, ethyl acrylate, methyl methacrylate, ethyl methacrylate, vinylidene chloride, acrylonitrile, vinyl carbazole, and acrylate having a polyalkylene structure. Or homopolymers or copolymers of monomers such as methacrylates or mixtures thereof. Among these, a copolymer containing polystyrene, styrene and acrylonitrile, and polymethyl methacrylate are preferable.

[Inorganic fine particles]
Among the fine particles, inorganic fine particles include metals and metal compounds such as oxides, composite oxides, hydroxides, carbonates, sulfates, silicates, phosphates, organic acid salts, nitrides and carbides. , Sulfides, and composites of at least two of these. Specifically, silica, alumina, magnesium oxide, titanium oxide, magnesium carbonate, calcium alginate, zircon oxide, tin oxide, potassium titanate, strontium titanate, aluminum borate, magnesium borate, aluminum hydroxide, magnesium hydroxide, water Calcium oxide, titanium hydroxide, basic magnesium sulfate, calcium carbonate, calcium sulfate, magnesium sulfate, calcium silicate, magnesium silicate, calcium phosphate, silicon nitride, titanium nitride, aluminum nitride, silicon carbide, titanium carbide, zinc sulfide and these The compound of at least 2 or more types of these is mentioned. Preferably, silica, alumina, magnesium oxide, titanium oxide, magnesium carbonate, calcium alginate, or a mixture thereof can be used.

The shape of the fine particles may be any shape such as a spherical shape, a needle shape, a flat plate shape, a feather shape, a chain shape (beaded shape), or an indefinite shape, but a spherical shape is preferable.
The average particle size of the fine particles is preferably 5 μm or less, more preferably 0.005 to 3 μm, and particularly preferably 0.01 to 2 μm.
A known method can be used to measure the particle diameter. Specific examples include laser diffraction / scattering methods, dynamic light scattering methods, static light scattering methods, dynamic imaging methods, static imaging methods, image analysis methods, and electron microscopy. For example, a fine particle-containing liquid is diluted with distilled water or the like so that the particle concentration is 0.1 to 1% by weight, and a commercially available average particle size measuring device (for example, LA-910 (manufactured by Horiba, Ltd.)) Can be measured easily. Furthermore, the dynamic light scattering method using the laser Doppler effect is preferable because it can measure the particle size up to a small size. In the planographic printing plate dummy plate, for example, a method of observing a section of the planographic printing plate dummy plate with an electron microscope or the like or a method of image analysis is preferable because the particle size can be easily measured. The average particle diameter of the fine particles is a numerical value measured using a laser diffraction / scattering method (measuring device: LA-920, manufactured by Horiba, Ltd.).

<Hydrophilic compound>
The lithographic printing plate dummy according to the present invention can contain a hydrophilic compound in at least one of the constituent layers (the first hydrophilic layer and the second hydrophilic layer). When the lithographic printing plate dummy plate is subjected to on-press development because the constituent layer contains a hydrophilic compound, the permeability of dampening water is further improved, and on-press development is further promoted, so that the edge It is thought that dirt is more eliminated.
In a preferred embodiment, the hydrophilic compound is a low molecular weight hydrophilic compound. The molecular weight of the low molecular weight hydrophilic compound is preferably 3000 or less, more preferably 2000 or less, and still more preferably 1000 or less. The molecular weight of the low molecular weight hydrophilic compound is usually 100 or more.

  A surfactant can be mentioned as a hydrophilic compound. Examples of the surfactant include an anionic surfactant, a nonionic surfactant, a cationic surfactant, and an amphoteric surfactant, and an anionic surfactant or a nonionic surfactant is preferable.

Anionic surfactants include fatty acid salts, abietic acid salts, hydroxyalkane sulfonates, alkane sulfonates, dialkyl sulfosuccinates, linear alkyl benzene sulfonates, branched alkyl benzene sulfonates, alkyl naphthalene sulfonates. Alkylphenoxy polyoxyethylene propyl sulfonates, polyoxyethylene aryl ether sulfate esters, polyoxyethylene alkyl sulfophenyl ether salts, N-methyl-N-oleyl taurine sodium, N-alkylsulfosuccinic acid monoamide disodium salts, Petroleum sulfonates, sulfated castor oil, sulfated beef tallow oil, fatty acid alkyl ester sulfate esters, alkyl sulfate esters, polyoxyethylene alkyl -Ter sulfate, fatty acid monoglyceride sulfate, polyoxyethylene alkylphenyl ether sulfate, polyoxyethylene styrylphenyl ether sulfate, alkyl phosphate, polyoxyethylene alkyl ether phosphate, polyoxyethylene alkylphenyl Examples thereof include ether phosphoric acid ester salts, partially saponified products of styrene-maleic anhydride copolymer, partially saponified products of olefin-maleic anhydride copolymer, and naphthalene sulfonate formalin condensates. Among these anionic surfactants, dialkyl sulfosuccinates, alkyl sulfate esters, polyoxyethylene aryl ether sulfate salts, and alkyl naphthalene sulfonates are particularly preferably used.
Specific examples include an anionic surfactant represented by the following formula (IA) or formula (IB).

In the above formula (IA), R ₁ represents a linear or branched alkyl group having 1 to 20 carbon atoms, p represents 0, 1 or 2, and Ar ₁ has 6 to 10 carbon atoms. Represents an aryl group, q represents 1, 2 or 3, and M ₁ ⁺ represents Na ⁺ , K ⁺ , Li ⁺ or NH ₄ ⁺ . When p is 2, a plurality of R ₁ may be the same as or different from each other.
In the above formula (IB), R ₂ represents a linear or branched alkyl group having 1 to 20 carbon atoms, m represents 0, 1 or 2, and Ar ₂ has 6 to 10 carbon atoms. Represents an aryl group, Y represents a single bond or an alkylene group having 1 to 10 carbon atoms, R ₃ represents a linear or branched alkylene group having 1 to 5 carbon atoms, and n is an integer of 1 to 100 M ₂ ⁺ represents Na ⁺ , K ⁺ , Li ⁺ or NH ₄ ⁺ . When m is 2, a plurality of R ₂ may be the same or different from each other, and when n is 2 or more, a plurality of R ₃ may be the same or different from each other.

In formula (IA) and formula (IB), preferred examples of R ₁ and R ₂ include CH ₃ , C ₂ H ₅ , C ₃ H ₇ or C ₄ H ₉ . Preferred examples of R _{3 include, -CH 2 -, - CH 2} CH 2 -, - CH 2 CH 2 CH 2 -, - CH 2 CH (CH 3) - can be mentioned, -CH ₂ is more preferable examples CH ₂ — may be mentioned. p and m are preferably 0 or 1, and p is particularly preferably 0. Y is preferably a single bond. n is preferably an integer of 1 to 20.

  Specific examples of the anionic surfactant represented by the formula (IA) or the formula (IB) include the following compounds.

  Nonionic surfactants include polyoxyethylene alkyl ethers, polyoxyethylene aryl 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, polyoxyethylene glycerin fatty acid partial esters, fatty acid diethanolamides, N , N-bis-2-hydroxyalkylamines, polyoxyethylene alkylamines, triethanolamine fatty acid esters, trialkylamines Oxide and the like. Among these nonionic surfactants, polyoxyethylene aryl ethers, polyoxyethylene-polyoxypropylene block copolymers and the like are preferable.

  Specifically, for example, polyoxyethylene naphthyl ether, polyoxyethylene alkylphenyl ether, polyoxyethylene lauryl ether, polyoxyethylene cetyl ether, polyoxyethylene alkyl ethers such as polyoxyethylene stearyl ether, polyoxyethylene stearate Polyoxyethylene alkyl esters such as sorbate, sorbitan monolaurate, sorbitan monostearate, sorbitan distearate, sorbitan monooleate, sorbitan sesquioleate, sorbitan alkyl esters such as sorbitan trioleate, glycerol monostearate, Nonionic surfactants such as monoglyceride alkyl esters such as glycerol monooleate.

  As the nonionic surfactant, a surfactant represented by the following formula (II-A) or formula (II-B) is preferably used.

In the above formula (II-A), R ¹ represents a hydrogen atom or an alkyl group having 1 to 100 carbon atoms, n and m each represent an integer of 0 to 100, and both n and m are 0. There is no.
In the formula (II-B), ^{R 2} represents a hydrogen atom or an alkyl group of carbon atoms 1 to 100, n and m each represents an integer of 0 to 100, both n and m are 0 There is no.

  Examples of the compound represented by the formula (II-A) include polyoxyethylene phenyl ether, polyoxyethylene methyl phenyl ether, polyoxyethylene octyl phenyl ether, polyoxyethylene nonyl phenyl ether, and the like. Examples of the compound represented by the formula (II-B) include polyoxyethylene naphthyl ether, polyoxyethylene methyl naphthyl ether, polyoxyethylene octyl naphthyl ether, and polyoxyethylene nonyl naphthyl ether.

  In the compound represented by the above formula (II-A) or formula (II-B), n (the number of repeating units of the oxyethylene chain) is preferably 3 to 50, more preferably 5 to 30. m (the number of repeating units of the oxypropylene chain) is preferably 0 to 10, more preferably 0 to 5. The polyoxyethylene part and the polyoxypropylene part may be present randomly or in blocks.

  Specific examples of the nonionic surfactant represented by the formula (II-A) or the formula (II-B) are shown below. The oxyethylene repeating unit and the oxypropylene repeating unit in the exemplified compound “Y-5” below may be in any form of a random bond or a block bond.

Of the above surfactants, an anionic surfactant is particularly preferably used. Of the above surfactants, sodium naphthalene sulfonate, sodium alkyl naphthalene sulfonate, or polyoxyethylene aryl ether is preferably used, and sodium naphthalene sulfonate or sodium t-butyl naphthalene sulfonate is more preferably used.
Two or more surfactants can be used in combination. For example, a combination of two or more different anionic surfactants or a combination of an anionic surfactant and a nonionic surfactant is preferable.

Examples of the cationic surfactant include alkylamine salts, quaternary ammonium salts, polyoxyalkylamine salts, polyethylene polyamine derivatives, and the like.
Examples of amphoteric surfactants include carboxybetaines, aminocarboxylic acids, sulfobetaines, aminosulfuric esters, imidazolines, and the like.

  The content of the surfactant is preferably 0.01 to 100% by mass with respect to the solid content of the constituent layer (first hydrophilic layer or second hydrophilic layer) containing the surfactant, and preferably 10 to 100%. % By mass is more preferable, and 30 to 100% by mass is even more preferable.

A phosphoric acid compound can also be used as the low molecular weight hydrophilic compound. Phosphoric acid compounds include phosphoric acid, metaphosphoric acid, primary ammonium phosphate, secondary ammonium phosphate, sodium dihydrogen phosphate, sodium monohydrogen phosphate, primary potassium phosphate, secondary potassium phosphate, tripolyphosphoric acid Sodium, potassium pyrophosphate, sodium hexametaphosphate and the like can be mentioned. Among these, sodium dihydrogen phosphate, sodium monohydrogen phosphate, and sodium hexametaphosphate can be preferably used.
The content of the phosphoric acid compound is preferably 0.01 to 100% by mass, preferably 10 to 100%, based on the solid content of the constituent layer (the first hydrophilic layer or the second hydrophilic layer) containing the phosphoric acid compound. % By mass is more preferable, and 30 to 100% by mass is even more preferable.

A phosphonic acid compound can also be used as the low molecular weight hydrophilic compound. Examples of the phosphonic acid compound used as the low molecular weight hydrophilic compound include ethylphosphonic acid, propylphosphonic acid, i-propylphosphonic acid, butylphosphonic acid, hexylphosphonic acid, octylphosphonic acid, dodecylphosphonic acid, octadecylphosphonic acid, 2- Hydroxyethylphosphonic acid and sodium or potassium salts thereof, methylphosphonic acid methyl, ethyl ethylphosphonic acid methyl, 2-hydroxyethylphosphonic acid methyl and other alkylphosphonic acid monoalkyl esters and their sodium or potassium salts, methylenediphosphonic acid And alkylene diphosphonic acids such as ethylene diphosphonic acid and sodium or potassium salts thereof.
The content of the phosphonic acid compound is preferably 0.01 to 100% by mass with respect to the solid content of the constituent layer (the first hydrophilic layer or the second hydrophilic layer) containing the phosphonic acid compound. % By mass is more preferable, and 30 to 100% by mass is even more preferable.

  An organic carboxylic acid compound can also be used as the low molecular weight hydrophilic compound. Examples of the organic carboxylic acid compound include tartaric acid, oxalic acid, citric acid, malic acid, lactic acid, gluconic acid, amino acids, and other organic carboxylic acids and salts thereof.

  Other examples of the low molecular weight hydrophilic compound include a compound having an amino group or a functional group having a polymerization inhibiting ability and a group that interacts with the surface of the aluminum support (for example, 1,4-diazabicyclo [2,2,2]). And octane (DABCO), 2,3,5,6-tetrahydroxy-p-quinone, chloranil, sulfophthalic acid, hydroxyethylethylenediaminetriacetic acid, dihydroxyethylethylenediaminediacetic acid, hydroxyethyliminodiacetic acid, and the like.

  A low molecular weight hydrophilic compound may be used by 1 type, and may mix and use 2 or more types as needed.

  Further, the lithographic printing plate dummy according to the present invention comprises a chelating agent, a secondary or tertiary amine, and a polymerization inhibitor in at least one of the constituent layers (first hydrophilic layer and second hydrophilic layer). Can be contained.

[Cutting of lithographic printing plate dummy]
The lithographic printing plate dummy is typically obtained by cutting in the production process of a lithographic printing plate dummy. Cutting can be performed using a known cutting method. Preferably, the methods described in JP-A-8-58257, JP-A-9-211843, JP-A-10-100556, and JP-A-11-52579 can be used.

  The planographic printing plate dummy plate preferably has a sagging shape at its end. The planographic printing plate dummy plate having a sag shape at the end portion is excellent in the edge stain prevention effect in combination with the end region of the first hydrophilic layer according to the present invention.

FIG. 1 is a diagram schematically showing a cross-sectional shape of a lithographic printing plate dummy plate. In FIG. 1, the lithographic printing plate dummy plate 1 has a sag 2 at its end. The distance X between the upper end of the end surface 1c of the planographic printing plate dummy plate 1 (the boundary point between the sagging 2 and the end surface 1c) and the extension line of the second hydrophilic layer surface 1a is referred to as "sag amount", and the planographic printing plate dummy plate The distance Y between the point at which one second hydrophilic layer surface 1a begins to sag and the extension line of the end surface 1c is referred to as "sag width". The amount of sag at the end of the planographic printing plate dummy is preferably 35 μm or more, and more preferably 40 μm or more. The upper limit of the sagging amount is preferably 150 μm from the viewpoint of preventing deterioration of on-press developability due to deterioration of the end surface condition. When the sagging amount is less than 35 μm, the ink adhering to the end portion is easily transferred to the blanket and may cause edge smearing. When the sagging amount range is 35 to 150 μm, if the sagging width is small, cracks are generated at the end portions, and the printing ink accumulates there, causing stains. In order to reduce the occurrence of such cracks, the sagging width is suitably in the range of 70 to 300 μm, and preferably in the range of 80 to 250 μm. The preferable range of the sag amount and the sag width is not related to the edge shape of the aluminum support surface 1b of the planographic printing plate dummy plate 1.
Usually, at the end portion of the lithographic printing plate dummy plate 1, the boundary B between the first hydrophilic layer and the aluminum support and the aluminum support surface 1b are also sagging as in the second hydrophilic layer surface 1a. Yes.

The end portion having the sagging can be formed, for example, by adjusting the cutting conditions of the lithographic printing plate dummy plate.
Specifically, it can be performed by adjusting the gap between the upper cutting blade and the lower cutting blade, the amount of biting, the blade edge angle, etc. in the slitter device used when cutting the lithographic printing plate dummy plate.
For example, FIG. 2 is a cross-sectional view showing a cutting portion of a slitter device. In the slitter device, a pair of upper and lower cutting blades 10 and 20 are arranged on the left and right. The cutting blades 10 and 20 are round blades on a circular plate, and the upper cutting blades 10a and 10b are supported on the rotating shaft 11 and the lower cutting blades 20a and 20b are supported on the rotating shaft 21 on the same axis. The upper cutting blades 10a and 10b and the lower cutting blades 20a and 20b are rotated in opposite directions. The planographic printing plate dummy plate 30 is cut into a predetermined width by passing between the upper cutting blades 10a and 10b and the lower cutting blades 20a and 20b. By adjusting the clearance between the upper cutting blade 10a and the lower cutting blade 20a and the clearance between the upper cutting blade 10b and the lower cutting blade 20b of the cutting portion of the slitter device, an end portion having a sag can be formed.

[Plate making method of lithographic printing plate dummy]
Below, the plate-making method of the lithographic printing plate dummy plate which concerns on this invention is illustrated. However, the plate making method of the planographic printing plate dummy plate is not particularly limited to the following method.
The lithographic printing plate dummy plate making method according to a preferred embodiment of the present invention is a lithographic dummy plate having a solution development processing step of removing the second hydrophilic layer with a developer having a pH of 2 to 14 containing a surfactant. This is the plate making method.
Hereinafter, a preferred embodiment of each step will be described in order for the plate making method of the planographic printing plate dummy plate of the present invention.
<Solution development process>
The solution development treatment can be performed by a method (developer treatment method) of removing the second hydrophilic layer with a developer having a pH of 2 to 14 (preferably 2 to 12).

(Developer processing method)
In the developing solution processing method, the lithographic printing plate dummy plate precursor is treated with a developing solution having a pH of 2 to 14, and the second hydrophilic layer is removed to produce a lithographic printing plate dummy plate.
According to the first preferred embodiment of the present invention, a developer having a pH of 2 to 12 is used. That is, in this embodiment, the second hydrophilic layer is removed by a developer having a pH of 2 to 12. In this embodiment, it is preferable that a surfactant or a water-soluble polymer compound is contained in the developer, whereby the development and the gum solution treatment can be performed simultaneously. Therefore, the post-water washing step is not particularly required, and the development-gum solution treatment can be performed with one solution.
Further, the pre-water washing step is not particularly required, and the protective layer can be removed simultaneously with the development-gum solution treatment. In the method for producing a lithographic printing plate dummy according to the present invention, after the development-gum treatment, for example, it is preferable to perform drying after removing excess developer using a squeeze roller.

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

  The development processing using the developer can be preferably performed by an automatic developing processor equipped with a developer supply means and a rubbing member. An automatic developing processor using a rotating brush roll as the rubbing member is particularly preferable. Further, the automatic processor preferably includes a means for removing excess developer such as a squeeze roller and a drying means such as a warm air device after the development processing means.

  The developer used for the developer processing in the present invention preferably contains an aqueous solution having a pH of 2 to 14, or a surfactant. The developer is preferably an aqueous solution containing water as a main component (containing 60% by mass or more of water), and in particular, an aqueous solution containing a surfactant (anionic, nonionic, cationic, amphoteric ion, etc.) An aqueous solution containing a water-soluble polymer compound is preferred. An aqueous solution containing both a surfactant and a water-soluble polymer compound is also preferred. The pH of the developer is more preferably 2 to 12, still more preferably 3.5 to 12, particularly preferably 6 to 12, and most preferably 6.5 to 10.5.

  The anionic surfactant used in the developer in the present invention is not particularly limited, but fatty acid salts, abietic acid salts, hydroxyalkanesulfonic acid salts, alkanesulfonic acid salts, dialkylsulfosuccinic acid salts, linear alkylbenzenesulfonic acid Salts, branched alkylbenzene sulfonates, alkylnaphthalene sulfonates, alkyl diphenyl ether (di) sulfonates, alkylphenoxy polyoxyethylene alkyl sulfonates, polyoxyethylene alkyl sulfophenyl ether salts, N-alkyl-N-oleyl Sodium taurine, disodium N-alkylsulfosuccinic acid monoamide, petroleum sulfonates, sulfated castor oil, sulfated beef oil, sulfate esters of fatty acid alkyl esters Alkyl sulfates, polyoxyethylene alkyl ether sulfates, fatty acid monoglyceride sulfates, polyoxyethylene alkyl phenyl ether sulfates, polyoxyethylene styryl phenyl ether sulfates, alkyl phosphate esters, polyoxyethylene alkyl ethers Phosphoric acid ester salts, polyoxyethylene alkylphenyl ether phosphoric acid ester salts, partial saponification products of styrene-maleic anhydride copolymer, partial saponification products of olefin-maleic anhydride copolymer, naphthalene sulfonate formalin condensates Etc. Of these, alkylbenzene sulfonates, alkylnaphthalene sulfonates, and alkyl diphenyl ether (di) sulfonates are particularly preferably used.

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

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

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

  Two or more surfactants may be used in the developer. The amount of the surfactant contained in the developer is preferably from 0.01 to 20% by mass, and more preferably from 0.1 to 10% by mass.

  Examples of the water-soluble polymer compound used in the developer in the present invention include soybean polysaccharide, modified starch, gum arabic, dextrin, fibrin derivatives (for example, carboxymethylcellulose, carboxyethylcellulose, methylcellulose, etc.) and modified products thereof, pullulan, Polyvinyl alcohol and its derivatives, polyvinyl pyrrolidone, polyacrylamide and acrylamide copolymer, vinyl methyl ether / maleic anhydride copolymer, vinyl acetate / maleic anhydride copolymer, styrene / maleic anhydride copolymer, polyvinyl sulfonic acid And salts thereof, polystyrenesulfonic acid and salts thereof, and the like.

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

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

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

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

  In order for carbonate ions and bicarbonate ions to be present in the developer, carbonate and bicarbonate may be added to the developer, or by adjusting the pH after adding carbonate or bicarbonate, Ions and bicarbonate ions may be generated. The carbonate and bicarbonate are not particularly limited, but are preferably alkali metal salts. Examples of the alkali metal include lithium, sodium, and potassium, and sodium is particularly preferable. Alkali metals may be used alone or in combination of two or more.

  The total amount of carbonate ions and bicarbonate ions is preferably 0.05 to 5 mol / L, more preferably 0.07 to 2 mol / L, and particularly preferably 0.1 to 1 mol / L with respect to the developer.

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

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

  In the present invention, in addition to the above components, the developer may contain a preservative, a chelate compound, an antifoaming agent, an organic acid, an inorganic acid, an inorganic salt, and the like. Specifically, compounds described in paragraph numbers [0266] to [0270] of JP-A-2007-206217 can be preferably used.

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

[Plate making method of lithographic printing plate precursor]
The plate-making method of the lithographic printing plate precursor according to a preferred embodiment of the present invention can be the same plate-making method as the plate-making method of the lithographic printing plate dummy plate described above.

[Printing method using planographic printing plate dummy]
Hereinafter, a printing method using the planographic printing plate dummy according to the present invention will be exemplified. However, the printing method using the planographic printing plate dummy plate is not particularly limited to the following method.
The printing method using the planographic printing plate dummy according to a preferred embodiment of the present invention typically involves exposing a planographic printing plate precursor and then exposing the planographic printing plate precursor to the planographic printing plate according to the present invention. This is a printing method including an on-press development process in which a plate dummy plate is set in a printing machine and the second hydrophilic layer of the planographic printing plate dummy plate is removed by supplying at least one of printing ink and dampening water.
Hereinafter, the preferable aspect of each process is demonstrated in order about the printing method using the lithographic printing plate dummy plate of this invention.

<On-machine development process>
The on-press development process can be performed by a method (on-press development method) of removing the second hydrophilic layer with at least one of printing ink and fountain solution on a printing press.

In the on-press development method, the lithographic printing plate dummy plate precursor is supplied with at least one of printing ink and fountain solution on the printing press, and the second hydrophilic layer is removed to produce a lithographic printing plate dummy plate. . That is, in this aspect, the second hydrophilic layer is removed by at least one of printing ink and fountain solution on the printing machine.
In this aspect, it is mounted on the printing machine as it is without any development processing, or after mounting the lithographic printing plate precursor on the printing machine, and then printing by supplying printing ink and fountain solution, At the initial stage of printing, the second hydrophilic layer of the planographic printing plate dummy plate is removed by dissolving or dispersing the second hydrophilic layer by at least one of the supplied printing ink and dampening water. The surface of the first hydrophilic layer of the planographic printing plate dummy plate is exposed at that portion. In this way, the lithographic printing plate dummy is developed on-press on a printing press and used as it is for printing a large number of sheets.

[Printing method using lithographic printing plate precursor]
The printing method using the planographic printing plate according to a preferred embodiment of the present invention can use the same printing method as the printing method using the planographic printing plate dummy plate described above.

  EXAMPLES Hereinafter, although an Example demonstrates this invention in detail, this invention is not limited to these. In addition, in the polymer compound, the molecular weight is a weight average molecular weight (Mw), and the ratio of the repeating units is a mole percentage except for those specifically defined.

[Example 1]
[Preparation of lithographic printing plate dummy]

<Preparation of aluminum support>
In order to remove rolling oil on the surface of a 0.3 mm thick aluminum plate (material JIS A 1050), after degreasing at 50 ° C. for 30 seconds using a 10 mass% sodium aluminate aqueous solution, the hair diameter is 0.3 mm. The surface of the aluminum plate was grained using 3 bundle-planted nylon brushes and a pumice-water suspension (specific gravity 1.1 g / cm ³ ) having a median diameter of 25 μm and washed well with water. Etching was performed by immersing the aluminum plate in a 25 mass% sodium hydroxide aqueous solution at 45 ° C for 9 seconds, washing with water, and further immersed in a 20 mass% nitric acid aqueous solution at 60 ° C for 20 seconds, followed by washing with water. The etching amount of the grained surface was about 3 g / m ² .

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

Subsequently, nitric acid electrolysis was performed with an aqueous solution of 0.5% by mass of hydrochloric acid (containing 0.5% by mass of aluminum ions) and an electrolytic solution having a liquid temperature of 50 ° C. under the condition of an electric quantity of 50 C / dm ² when the aluminum plate was the anode Electrochemical surface roughening treatment was carried out in the same manner as above, followed by washing with water by spraying.
Next, a 2.5 g / m ² direct current anodic oxide film with a current density of 15 A / dm ² is provided on an aluminum plate as an electrolyte using a 15 mass% sulfuric acid aqueous solution (containing 0.5 mass% of aluminum ions), and then washed with water. , Dried.
Thereafter, in order to ensure the hydrophilicity of the non-image area, the aluminum plate was subjected to silicate treatment at 60 ° C. for 10 seconds using an aqueous 2.5 mass% No. 3 sodium silicate solution, and then washed with water to produce an aluminum support. did. The adhesion amount of Si was 10 mg / m ² . When the center line average roughness (Ra) of the aluminum support was measured using a needle having a diameter of 2 μm, it was 0.51 μm.

<Preparation of first hydrophilic layer coating solution>
A first hydrophilic layer coating solution a-1 having the following composition was prepared.
(First hydrophilic layer coating solution a-1)
-High molecular compound B-1 (following structure) 0.18g
Colorant: Compound A-1 (the following structure) 0.03 g
Surfactant (Emalex 710, manufactured by Nippon Emulsion Co., Ltd.) (corresponding to hydrophilic compound C-3 described later) 0.03 g
・ Ion-exchanged water 28.0g

In the polymer compound B-1, M ¹ , M ² , and M ³ each independently represent a hydrogen atom or a sodium atom. The number on the right side of the parenthesis represents the content (mol%) of each monomer unit with respect to the total monomer units of the polymer.

  Compound A-1: Acid Red 73 (trade name: WATER RED3, manufactured by Orient Chemical Industry Co., Ltd.)

<Preparation of second hydrophilic layer coating solution>
A second hydrophilic layer coating solution b-1 having the following composition was prepared.
(Second hydrophilic layer coating solution b-1)
・ Synthetic mica (Somasif ME-100, 8% aqueous dispersion, manufactured by Coop Chemical Co., Ltd.)
0.41g
Compound D-1 Polyvinyl alcohol (CKS-50: degree of saponification 99 mol%, degree of polymerization 300, manufactured by Nippon Synthetic Chemical Industry Co., Ltd.) 0.26 g
・ Carboxymethylcellulose (Serogen PR, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) 0.11 g
Surfactant-1 (BASF, Pluronic P-84) (corresponding to hydrophilic compound C-2 described later) 0.01 g
Surfactant-2 (manufactured by Nippon Emulsion Co., Ltd., Emalex 710) (corresponding to hydrophilic compound C-3 described later) 0.02 g
・ Ion exchange water 6g

<Application of coating solution and cutting of lithographic printing plate dummy>
The application of each coating solution and the cutting of the planographic printing plate dummy plate were performed in the order of the first hydrophilic layer coating solution coating step, the second hydrophilic layer coating solution coating step, and the cutting step.
The coating process of the first hydrophilic layer was performed by applying the first hydrophilic layer coating solution with a bar so that the dry coating amount was 250 mg / m ² . Drying was performed for 1 minute at 100 ° C. using a thermostat PH-201 manufactured by ESPEC Corporation.
The coating process of the second hydrophilic layer was performed by applying the second hydrophilic layer coating solution with a bar so that the dry coating amount was 1800 mg / m ² . Drying was performed for 75 seconds at 125 ° C. using a thermostat PH-201 manufactured by ESPEC Corporation.
In the cutting step, the planographic printing plate dummy plate is adjusted using a rotary blade as shown in FIG. 2 to adjust the gap, biting amount and blade edge angle between the upper cutting blade and the lower cutting blade, and the desired sag amount and It was carried out so as to have an end shape having a sagging width. When the sagging shape was measured by the following method, the sagging amount was a value shown in Table 10.
The sagging shape was measured using a surface roughness meter (Surfcom) manufactured by Tokyo Seimitsu Co., Ltd. A model 480A was used as the surface roughness meter, and a stylus having a diameter of 2 μm was used. The stylus was moved from about 1 mm inside the lithographic printing plate precursor end to the end at a speed of 3 mm / sec, and the shape was measured.

[Examples 2-3]
[Preparation of lithographic printing plate dummy]
The same procedure as in Example 1 was conducted except that only the content of the polymer compound having a support-adsorbing group and a hydrophilic group contained in the first hydrophilic layer coating solution was changed to the amount shown in Table 10 below. A lithographic printing plate dummy plate was prepared.

[Example 4]
[Preparation of lithographic printing plate dummy]
A lithographic printing plate dummy plate in the same manner as in Example 2 except that the polymer compound having a support-adsorbing group and a hydrophilic group contained in the first hydrophilic layer coating solution was changed to the following compound B-2. Was made.

[Example 5]
[Preparation of lithographic printing plate dummy]
A lithographic printing plate dummy plate was produced in the same manner as in Example 2 except that the first hydrophilic layer coating solution further contained fine particles I. The first hydrophilic layer coating solution a-5 was prepared by adding 0.075 g of fine particles I to the first hydrophilic layer coating solution a-2.

[Examples 6 to 8]
[Preparation of lithographic printing plate dummy]
A lithographic printing plate dummy plate was produced in the same manner as in Example 5 except that the fine particles I of the first hydrophilic layer coating solution a-5 were replaced with the fine particles II, III, and IV as shown in Table 10. .

  The fine particles I, II, III and IV are as follows.

Fine particles I: Organic resin fine particles Organic resin fine particles prepared by the following method were used.
<Preparation of organic resin fine particles>
In a 1000 ml three-necked flask, 8 g of styrene, 1 g of divinylbenzene and 0.45 g of sodium dodecyl sulfate were weighed, dissolved in 28 g of distilled water, and stirred for 30 minutes at 65 ° C. under a nitrogen stream. To this solution was added a solution prepared by dissolving 18.6 mg of 2,2′-azobis (2-amidinopropane) dihydrochloride in 2 g of distilled water, and the mixture was stirred at the same temperature for 6 hours. After completion of the reaction, the reaction mixture was filtered through a glass filter to obtain an organic resin fine particle aqueous dispersion. The solid content concentration of the organic resin fine particle aqueous dispersion is 20% by mass, and the average particle diameter of the organic resin fine particles measured by a laser diffraction / scattering particle size distribution measuring device (LA-920, manufactured by Horiba, Ltd.) is It was 87 nm.

Microparticle II: Microgel A microgel prepared by the following method was used.
<Preparation of microgel>
As an oil phase component, trimethylolpropane and xylene diisocyanate adduct (Mitsui Chemical Polyurethane Co., Ltd., Takenate D-110N) 10 g, pentaerythritol triacrylate (Nippon Kayaku Co., Ltd., SR444) 3.15 g and 0.1 g of alkylbenzene sulfonate (manufactured by Takemoto Yushi Co., Ltd., Pionin A-41C) was dissolved in 17 g of ethyl acetate. As an aqueous phase component, 40 g of a 4 mass% aqueous solution of polyvinyl alcohol (manufactured by Kuraray Co., Ltd., PVA-205) was prepared. The oil phase component and the aqueous phase component were mixed and emulsified for 10 minutes at 12,000 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 50 ° C. for 3 hours. The microgel solution thus obtained was diluted with distilled water to a solid content concentration of 15% by mass to prepare a microgel. The average particle size of the microgel measured by a laser diffraction / scattering particle size distribution analyzer (LA-920, manufactured by HORIBA, Ltd.) was 0.2 μm.

Fine particles III: Thermoplastic fine particles Thermoplastic fine particles prepared by the following method were used.
<Preparation of thermoplastic fine particle aqueous dispersion>
A 1000 ml four-necked flask is equipped with a stirrer, thermometer, dropping funnel, nitrogen inlet tube, reflux condenser, and introduced with nitrogen gas, deoxygenated, and polyethylene glycol methyl ether methacrylate (average repeat of PEGMA ethylene glycol) Number of units: 20) 10 g, distilled water 200 g and n-propanol 200 g were added and heated until the internal temperature reached 70 ° C. Next, a premixed mixture of 10 g of styrene (St), 80 g of acrylonitrile (AN) and 0.8 g of 2,2′-azobisisobutyronitrile was added dropwise over 1 hour. After completion of the dropwise addition, the reaction was continued for 5 hours, and then 0.4 g of 2,2′-azobisisobutyronitrile was added to raise the internal temperature to 80 ° C. Subsequently, 0.5 g of 2,2′-azobisisobutyronitrile was added over 6 hours. Polymerization proceeded at 98% or more at the stage of reaction for a total of 20 hours, and an aqueous dispersion of thermoplastic fine particles having a mass ratio of PEGMA / St / AN = 10/10/80 was obtained. The average particle diameter of the thermoplastic fine particles measured by a laser diffraction / scattering particle size distribution analyzer (LA-920, manufactured by Horiba, Ltd.) was 150 nm.

Fine particles IV: inorganic fine particles Commercially available colloidal silica MP1040 (manufactured by Nissan Chemical Industries, Ltd./average particle size 0.1 μm / 40 mass% aqueous dispersion) was used.

[Example 9]
[Preparation of lithographic printing plate dummy]
A lithographic printing plate dummy plate was produced in the same manner as in Example 2 except that the first hydrophilic layer coating solution further contained the hydrophilic compounds listed in Table 10 below. It prepared by adding 0.25g of hydrophilic compound C-1 (solid content concentration of 30 wt%) of Table 1 to the 1st hydrophilic layer coating liquid a-2.

Hydrophilic compound C-1: anionic surfactant 4- (2- (2- (2-ethylhexyloxy) ethoxy) ethoxy) butane-1-sulfonic acid sodium, manufactured by Wako Pure Chemical Industries, Ltd.

[Examples 10 to 17]
[Preparation of lithographic printing plate dummy]
Example 9 except that the hydrophilic compound C-1 of the first hydrophilic layer coating solution a-9 was replaced so that the solid content concentrations of the hydrophilic compounds C-2 to C-9 in Table 10 were the same. Similarly, a lithographic printing plate dummy plate was produced. The hydrophilic compounds C-2 to C-9 in Table 1 are as follows.

Hydrophilic compound C-2: nonionic surfactant Pluronic P-84, manufactured by BASF

Hydrophilic compound C-3: nonionic surfactant Emalex 710, manufactured by Nippon Emulsion Co., Ltd.

Hydrophilic compound C-4: Malic acid, manufactured by Fuso Chemical Industry Co., Ltd.

Hydrophilic compound C-5: Betaine, manufactured by Iwase Cosfa

Hydrophilic compound C-6: sulfophthalic acid (50 wt%), manufactured by Tokyo Chemical Industry Co., Ltd.

Hydrophilic compound C-7: hydroxyethyliminodiacetic acid, manufactured by Inabata Sangyo Co., Ltd.

Hydrophilic compound C-8: sodium dihydrogen phosphate, manufactured by Wako Pure Chemical Industries, Ltd.

Hydrophilic compound C-9: sodium naphthalene sulfonate, manufactured by Wako Pure Chemical Industries, Ltd.

[Example 18]
[Preparation of lithographic printing plate dummy]
A lithographic printing plate dummy was prepared in the same manner as in Example 2 except that the second hydrophilic layer coating solution further contained the hydrophilic compound C-1 shown in Table 10 below. 0.05g of hydrophilic compound C-1 was added to the 2nd hydrophilic layer coating liquid b-1, and the 2nd hydrophilic layer coating liquid b-2 was prepared.

[Example 19]
[Production of lithographic printing plate dummy]
A lithographic printing plate dummy plate was produced in the same manner as in Example 18 except that the first hydrophilic layer coating solution a-2 was replaced with the first hydrophilic layer coating solution a-9.

[Example 20]
[Preparation of lithographic printing plate dummy]
A lithographic printing plate dummy plate was prepared in the same manner as in Example 19 except that the first hydrophilic layer coating solution a-9 further contained fine particles II shown in Table 10 below. The first hydrophilic layer coating solution a-18 was prepared by adding 0.075 g of fine particles II to the first hydrophilic layer coating solution a-9.

[Example 21]
[Preparation of lithographic printing plate dummy]
A lithographic printing plate dummy plate was produced in the same manner as in Example 2 except that the second hydrophilic layer coating solution b-1 was replaced with the second hydrophilic layer coating solution b-3 prepared as follows.

A second hydrophilic layer coating solution b-3 having the following composition was prepared.
(Second hydrophilic layer coating solution b-3)
Compound D-2 (the following structure) (the following structure, Mw: 30,000) (solid content)
0.03g
-6% by mass aqueous solution of polyvinyl alcohol (manufactured by Nippon Synthetic Chemical Industry Co., Ltd., CKS50, sulfonic acid modification, saponification degree 99 mol% or more, polymerization degree 300) (corresponding to the above-mentioned compound D-1) 0.10 g
・ Polyvinyl alcohol (manufactured by Kuraray Co., Ltd., PVA-405, 0.03 g
1% by weight aqueous solution of a 6% by weight aqueous solution / surfactant (Emalex 710, manufactured by Nippon Emulsion Co., Ltd.) (corresponding to the aforementioned hydrophilic compound C-3) 0 .86g
・ Ion-exchanged water 6.0g

[Examples 22 to 24]
[Preparation of lithographic printing plate dummy]
A lithographic printing plate dummy plate was prepared in the same manner as in Example 2 except that the colorant contained in the first hydrophilic layer coating solution was a compound shown in Table 10 below.

Compound A-2 (Acid Red 18) (trade name: WATER RED 1, manufactured by Orient Chemical Industry Co., Ltd.)

Compound A-3 (Acid Yellow 42) (trade name: WATER Yellow 6C, manufactured by Orient Chemical Co., Ltd.)

Compound A-4 (Tartrazine, manufactured by Eisen Co., Ltd.)

[Example 25]
[Preparation of lithographic printing plate dummy]
A lithographic printing plate dummy plate was prepared in the same manner as in Example 2 except that the second hydrophilic layer coating solution further contained 0.01 g of the colorant A-1 shown in Table 10 below.

[Example 26]
[Preparation of lithographic printing plate dummy]
The same as in Example 2 except that the first hydrophilic layer coating solution does not contain a colorant, and the second hydrophilic layer coating solution further contains 0.01 colorant A-1 shown in Table 10 below. Thus, a lithographic printing plate dummy plate was prepared.

[Example 27]
[Preparation of lithographic printing plate dummy]
The same as in Example 2 except that the first hydrophilic layer coating solution did not contain a surfactant and the second hydrophilic layer coating solution did not contain surfactant-1 and surfactant-2. Thus, a lithographic printing plate dummy plate was prepared.

[Example 28]
[Preparation of lithographic printing plate dummy]
A lithographic printing plate dummy plate was produced in the same manner as in Example 2 except that the second hydrophilic layer coating solution b-1 was replaced with the second hydrophilic layer coating solution b-6 prepared as follows. .

<Preparation of Art Pearl J-7P aqueous dispersion>
3 g of nonionic surfactant (Emulex 710, manufactured by Nippon Emulsifier Co., Ltd.) and 3 g of carboxymethylcellulose (Delogen Kogyo Seiyaku Co., Ltd. Cellogen PR) in 74 g of ion-exchanged water for the purpose of improving dispersion stability. Add and dissolve. To this aqueous solution, 20.0 g of silica composite crosslinked acrylic resin particles (manufactured by Negami Kogyo Co., Ltd., Art Pearl J-7P) is added, and dispersed for 15 minutes at 10,000 rpm with an ace homogenizer manufactured by Nippon Seiki Seisakusho. Art Pearl J-7P aqueous dispersion was obtained.

Next, a second hydrophilic layer coating solution b-6 having the following composition was prepared.
(Second hydrophilic layer coating solution b-5)
・ Synthetic mica (Somasif ME-100, 8% aqueous dispersion, manufactured by Coop Chemical Co., Ltd.)
0.41g
Compound D-1 Polyvinyl alcohol (CKS-50: degree of saponification 99 mol%, degree of polymerization 300, manufactured by Nippon Synthetic Chemical Industry Co., Ltd.) 0.26 g
・ Carboxymethylcellulose (Serogen PR, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) 0.11 g
Surfactant-1 (manufactured by BASF, Pluronic P-84) (corresponding to the aforementioned hydrophilic compound C-2) 0.01 g
Surfactant-2 (manufactured by Nippon Emulsion Co., Ltd., Emalex 710) (corresponding to the aforementioned hydrophilic compound C-3) 0.02 g
・ Silica composite crosslinked acrylic resin particles (Art Pearl J-7P aqueous dispersion) 0.07 g
・ Ion exchange water 6g

[Comparative Example 1]
A lithographic printing plate dummy plate was produced in the same manner as in Example 21 of JP2012-116165A.

A first hydrophilic layer coating solution a-24 (undercoat layer coating solution U-1 of JP 2012-116165 A) having the following composition was prepared.
(First hydrophilic layer coating solution a-24)
・ Polymer compound B-3 (the following structure) 0.3 g
・ Pure water 60.0g
・ Methanol 939.7g

A non-photosensitive layer coating solution c-1 (non-photosensitive layer coating solution M-1 of JP2012-116165A) having the following composition was prepared.
(Non-photosensitive layer coating solution c-1)
・ Binder polymer A 0.70g
・ Phosphoric acid (85% by weight aqueous solution) 0.08 g
・ Sulfophthalic acid (50 wt% aqueous solution) 0.05g
・ Tricarballylic acid 0.025g
Colorant (VPB-Naps (Victoria Pure Blue naphthalene sulfonate): manufactured by Hodogaya Chemical Co., Ltd.) 0.0014 g
Colorant Curcumin Absorption maximum wavelength (λmax) in methanol of 430 nm
0.027g
・ The following plasticizer A 0.115g
-Fluorosurfactant (Megafac F-780-F: Dainippon Ink Chemical Co., Ltd., 30% by weight solution of MEK) 0.009 g
・ Methyl ethyl ketone (MEK) 7.10g
・ Methanol 5.65g
1-methoxy-2-propanol (MFG) 1.80 g
The binder polymer A is a 16% by weight solution of MFG / MEK = 1/1, a weight average molecular weight of 75,000, an acid content of 1.58 meq / g, and five types of monomers (1) to (5) below. This is a condensation reaction product.
(1) 4,4-diphenylmethane diisocyanate 42.5 mol%
(2) Hexamethylene diisocyanate 7.5 mol%
(3) 2,2-bis (hydroxymethyl) propionic acid 30.0 mol%
(4) Methacryloyloxymethyl ethylene glycol 17.5 mol%
(5) Polyethylene glycol 2.5 mol%

[Comparative Example 2]
A lithographic printing plate dummy was prepared in the same manner as in Example 2 except that the solid content concentration of the first hydrophilic layer coating solution a-24 of Comparative Example 1 was increased and applied so as to have a dry coating amount shown in Table 10. A plate was made.

A first hydrophilic layer coating solution a-25 having the following composition was prepared.
(First hydrophilic layer coating solution a-25)
・ High molecular compound B-3 15.0 g
・ Pure water 58.8g
・ Methanol 926.2g

[Preparation of lithographic printing plate precursor]
<Production of support>
The following treatments (a) to (m) were applied to an aluminum alloy plate having a thickness shown in Table A having a composition shown in Table A to prepare a support. In addition, the water washing process was performed between all the process steps, and the liquid draining was performed with the nip roller after the water washing process.

(A) Mechanical roughening treatment (brush grain method)
Using an apparatus as shown in FIG. 3, mechanical roughening is performed by a rotating bundle-planting brush while supplying a suspension of pumice (specific gravity: 1.1 g / cm ³ ) as a polishing slurry to the surface of an aluminum plate. Processed. In FIG. 3, 41 is an aluminum plate, 42 and 44 are roller brushes (bundle brushes), 43 is an abrasive slurry, and 45, 46, 47 and 48 are support rollers.

  The mechanical surface roughening treatment was performed with the median diameter of the abrasive pumice being 30 μm, the number of bundled brushes being 4, and the number of rotations of the bundled brush being 250 rpm. The material of the bunch planting brush was 6 · 10 nylon, with a bristle diameter of 0.3 mm and a bristle length of 50 mm. The bundle-planting brush is a tube made by making a hole in a stainless steel tube of φ300 mm so as to be dense. The distance between the two support rollers (φ200 mm) at the bottom of the bundle-planting brush was 300 mm. The bundle brush was pressed until the load of the drive motor for rotating the brush became 10 kW plus with respect to the load before the bundle brush was pressed against the aluminum plate. The rotation direction of the bundle planting brush was the same as the movement direction of the aluminum plate.

(B) Alkaline etching treatment An aluminum plate was etched by spraying an aqueous caustic soda solution having a caustic soda concentration of 26 mass% and an aluminum ion concentration of 6.5 mass% with a spray tube at a temperature of 70 ° C. Then, water washing by spraying was performed. The amount of dissolved aluminum was 10 g / m ² .

(C) Desmutting treatment in acidic aqueous solution Next, desmutting treatment was performed in an aqueous nitric acid solution. The nitric acid aqueous solution used for the electrochemical roughening in the next step was used as the nitric acid aqueous solution used for the desmut treatment. The liquid temperature was 35 ° C. The desmutting treatment was performed by spraying a desmutting solution for 3 seconds.

(D) Electrochemical roughening treatment An electrochemical roughening treatment was carried out continuously using an alternating voltage of 60 Hz. As the electrolytic solution, an electrolytic solution in which aluminum nitrate was added to an aqueous solution having a temperature of 35 ° C. and nitric acid was 10.4 g / L to adjust the aluminum ion concentration to 4.5 g / L was used. The AC power supply waveform is subjected to electrochemical surface roughening using a carbon electrode as a counter electrode using a trapezoidal rectangular wave alternating current with a time tp of 0.8 msec until the current value reaches a peak from zero, a duty ratio of 1: 1. went. Ferrite was used for the auxiliary anode. The electrolytic cell shown in FIG. 4 was used. In FIG. 4, an aluminum plate W is wound around a radial drum roller 52 disposed so as to be immersed in the main electrolytic cell 50, and subjected to electrolytic treatment by main electrodes 53a and 53b connected to an AC power source 51 in the course of conveyance. The electrolytic solution 55 was supplied from the electrolytic solution supply port 54 through the slit 56 to the electrolytic solution passage 57 between the radial drum roller 52 and the main electrodes 53a and 53b. The aluminum plate W treated in the main electrolytic cell 50 was then electrolytically treated in the auxiliary anode cell 60. An auxiliary anode 58 is disposed opposite to the aluminum plate W in the auxiliary anode tank 60, and the electrolytic solution 55 is supplied so as to flow in the space between the auxiliary anode 58 and the aluminum plate W. The current density was 30 A / dm ² at the peak current value, and 5% of the current flowing from the power source was shunted to the auxiliary anode. The amount of electricity was 185 C / dm ^{2 as} the total amount of electricity when the aluminum plate was an anode. Then, water washing by spraying was performed.

(E) Alkaline etching treatment An aluminum plate was etched by spraying an aqueous caustic soda solution having a caustic soda concentration of 5 mass% and an aluminum ion concentration of 0.5 mass% with a spray tube at a temperature of 50C. Then, water washing by spraying was performed. The amount of dissolved aluminum was 0.5 g / m ² .

(F) Desmutting treatment in acidic aqueous solution Next, desmutting treatment was performed in an aqueous sulfuric acid solution. In the desmutting treatment, an aqueous sulfuric acid solution having a sulfuric acid concentration of 170 g / L and an aluminum ion concentration of 5 g / L was used. The liquid temperature was 60 ° C. The desmutting treatment was performed by spraying a desmutting solution for 3 seconds.

(G) Electrochemical surface roughening treatment An electrochemical surface roughening treatment was performed continuously using an alternating voltage of 60 Hz. As the electrolytic solution, an electrolytic solution in which aluminum chloride was adjusted to 4.5 g / L by adding aluminum chloride to an aqueous solution having a liquid temperature of 35 ° C. and hydrochloric acid of 6.2 g / L was used. The AC power supply waveform is subjected to electrochemical surface roughening using a carbon electrode as a counter electrode using a trapezoidal rectangular wave alternating current with a time tp of 0.8 msec until the current value reaches a peak from zero, a duty ratio of 1: 1. went. Ferrite was used for the auxiliary anode. The electrolytic cell shown in FIG. 4 was used. The current density was 25A / dm ² at the peak of electric current amount in hydrochloric acid electrolysis of the aluminum plate was 63C / dm ² as the total quantity of electricity when the anode. Then, water washing by spraying was performed.

(H) Alkaline etching treatment An aluminum plate was etched by spraying a caustic soda aqueous solution having a caustic soda concentration of 5 mass% and an aluminum ion concentration of 0.5 mass% with a spray tube at a temperature of 50C. Then, water washing by spraying was performed. The amount of aluminum dissolved was 0.1 g / m ² .

(I) Desmutting treatment in acidic aqueous solution Next, desmutting treatment was performed in an aqueous sulfuric acid solution. Using an aqueous sulfuric acid solution used in the anodizing treatment step (containing 5 g / L of aluminum ions in an aqueous solution of 170 g / L sulfuric acid), desmut treatment was performed at a liquid temperature of 35 ° C. for 4 seconds. The desmutting liquid was sprayed and sprayed for 3 seconds.

(J) First Anodizing Treatment A first stage anodizing treatment was performed using a direct current electrolysis anodizing apparatus having the structure shown in FIG. Anodization was performed under the conditions shown in Table B to form an anodized film having a predetermined film thickness. As the electrolytic solution, an aqueous solution containing the components shown in Table B was used. In Tables B to D, “component concentration” represents the concentration (g / l) of each component described in the “Liquid component” column.

  In the anodizing apparatus 610 shown in FIG. 5, the aluminum plate 616 is conveyed as shown by the arrow in FIG. The aluminum plate 616 is charged (+) by the power supply electrode 620 in the power supply tank 612 in which the electrolytic solution 618 is stored. Then, the aluminum plate 616 is conveyed upward by the roller 622 in the power supply tank 612, and the direction is changed downward by the nip roller 624. Then, the aluminum plate 616 is conveyed toward the electrolytic treatment tank 614 in which the electrolytic solution 626 is stored, and by the roller 628. The direction is changed horizontally. Next, the aluminum plate 616 is charged to (−) by the electrolytic electrode 630 to form an anodized film on the surface thereof, and the aluminum plate 616 exiting the electrolytic treatment tank 614 is transported to a subsequent process. In the anodizing apparatus 610, the direction changing means is constituted by the roller 622, the nip roller 624 and the roller 628, and the aluminum plate 616 is disposed between the power supply tank 612 and the electrolytic treatment tank 614 in the above-described rollers 622, 624 and 628. Thus, it is conveyed into a mountain shape and an inverted U shape. The feeding electrode 620 and the electrolytic electrode 630 are connected to a DC power source 634.

(K) Second Anodizing Treatment A second stage anodizing treatment was performed using a direct current electrolysis anodizing apparatus having the structure shown in FIG. Anodization was performed under the conditions shown in Table C to form an anodized film having a predetermined film thickness. As the electrolytic solution, an aqueous solution containing the components shown in Table C was used.

(L) Third Anodizing Treatment A third stage anodizing treatment was performed using a direct current electrolysis anodizing apparatus having the structure shown in FIG. Anodization was performed under the conditions shown in Table D to form an anodized film having a predetermined film thickness. As the electrolytic solution, an aqueous solution containing the components shown in Table D was used.

(M) Hydrophilization treatment In order to ensure the hydrophilicity of the non-image area, a silicate treatment was performed by dipping at 50 ° C. for 7 seconds using a 2.5 mass% No. 3 sodium silicate aqueous solution. The adhesion amount of Si was 8.5 mg / m ² . Then, water washing by spraying was performed.

  The average diameter (surface layer average diameter) of the large-diameter hole portion in the anodic oxide film having the micropores obtained above, the average diameter (bottom average diameter) at the communicating position of the large-diameter hole portion, and the small-diameter hole Average diameter (small-diameter hole diameter), average depth of large-diameter holes and small-diameter holes, thickness of anodized film from the bottom of small-diameter holes to the aluminum plate surface (barrier layer thickness), small-diameter Table E shows the hole density and the like. The small diameter hole portion includes a first small diameter hole portion and a second small diameter hole portion having different depths, and the deeper one is referred to as a first small diameter hole portion.

  In Table E, the average value and the minimum value are shown as the barrier layer thickness. The average value of the barrier layer thickness is obtained by observing the cross section of the support (anodized film) with FE-TEM at a magnification of 500,000 times, and in the obtained image, from the bottom of the first small-diameter hole to the aluminum plate surface. The thickness of the anodic oxide film was measured at 50 locations, and they were arithmetically averaged.

The average diameter of the micropores (average diameter of the large-diameter hole portion and the small-diameter hole portion) was obtained by observing N = 4 sheets of the large-diameter hole surface and the small-diameter hole surface with an FE-SEM at a magnification of 150,000 times. In the four images, the diameters of the micropores (large-diameter holes and small-diameter holes) existing in the range of 400 × 600 nm ² were measured and averaged. In addition, when the depth of the large-diameter hole portion was deep and it was difficult to measure the diameter of the small-diameter hole portion, the upper part of the anodized film was cut, and thereafter various diameters were obtained.
The average depth of the large-diameter hole is determined by observing the cross section of the support (anodized film) with FE-TEM at a magnification of 500,000 times, and in the obtained image, the distance from the surface of any micropore to the communication position This is a value obtained by measuring 60 (N = 60) and averaging them. In addition, the average depth of the small-diameter hole portion is obtained by observing the cross section of the support (anodized film) with FE-SEM (50,000 times) and measuring the depth of 25 arbitrary micropores in the obtained image. The average value.

“Communication density” means the density of small-diameter holes in the cross-section of the anodized film. “Surface area increase ratio” means a value calculated based on the following formula (A).
Formula (A)
Surface area increase ratio = 1 + pore density × (π × (surface layer average diameter / 2 + bottom portion average diameter / 2) × ((bottom portion average diameter / 2−surface layer average diameter / 2) ² + depth A ² ) ^1/2 + π × (Bottom average diameter / 2) ² −π × (surface layer average diameter / 2) ² )
In the “average depth (nm)” column of the small diameter hole portion, the average depth of the second small diameter hole portion is shown on the left side, and the average depth of the first small diameter hole portion is shown on the right side. In the “communication density” column of the small diameter hole in Table E, the density of the first small diameter hole is shown in parentheses together with the communication density of the small diameter hole.
Further, the average diameter of the first small-diameter holes located from the bottom of the second small-diameter holes to the bottom of the first small-diameter holes was about 12 nm.

<Formation of undercoat layer>
On the support, an undercoat layer coating solution (1) having the following composition was applied so that the dry coating amount was 20 mg / m ² to form an undercoat layer.
(Undercoat layer coating solution (1))
・ Undercoat layer compound (1) (the following structure) 0.18 g
・ Hydroxyethyliminodiacetic acid 0.05g
・ Surfactant (Emalex 710, manufactured by Nippon Emulsion Co., Ltd.)
0.03g
・ Water 28.0g

<Formation of image recording layer>
On the undercoat layer, an image recording layer coating solution (1) having the following composition was bar-coated and then oven-dried at 100 ° C. for 60 seconds to form an image recording layer having a dry coating amount of 1.0 g / m ² .
The image recording layer coating solution (1) was obtained by mixing and stirring the following photosensitive solution (1) and microgel solution (1) immediately before coating.

(Image recording layer coating solution (1))
(Photosensitive solution (1))
-Binder polymer (1) (the following structure) 0.240 g
(Mw: 55,000, n: 2 (number of EO units))
・ Infrared absorber (1) (the following structure) 0.020 g
Borate compound (1) 0.010 g
Sodium tetraphenylborate-polymerization initiator (1) (the following structure) 0.162 g
・ Polymerizable compound 0.192g
Tris (acryloyloxyethyl) isocyanurate (NK ester A-9300, manufactured by Shin-Nakamura Chemical Co., Ltd.)
・ Anionic surfactant 1 (the following structure) 0.050 g
・ Fat Sensitizer 0.055g
Phosphonium compound (1) (the following structure)
・ Fat Sensitizer 0.018g
Benzyldimethyloctylammonium ・ PF ₆ salt ・ Sensitizer 0.040 g
Ammonium group-containing polymer (following structure)
(Mw: 50,000, reduced specific viscosity 45 ml / g)
・ Fluorosurfactant (1) (the following structure) 0.008g
・ 2-butanone 1.091g
・ 1-methoxy-2-propanol 8.609g

(Microgel solution (1))
・ Microgel (1) 2.640 g
・ Distilled water 2.425g

(Preparation of microgel (1))
As an oil phase component, 4.46 g of a polyfunctional isocyanate having the following structure (Mitsui Chemicals; 75 mass% ethyl acetate solution), trimethylolpropane (6 mol) and xylene diisocyanate (18 mol) were added to this, 10 g of an adduct (made by Mitsui Chemicals Polyurethane; 50% by mass ethyl acetate solution) to which polyoxyethylene (one mole, number of repeating oxyethylene units: 90) is added, pentaerythritol triacrylate (Nippon Kayaku Co., Ltd.) ), SR444) 3.15 g and Piionin A-41C (Takemoto Yushi Co., Ltd.) 0.1 g were dissolved in ethyl acetate 17 g. As an aqueous phase component, 40 g of a 4 mass% aqueous solution of polyvinyl alcohol (manufactured by Kuraray Co., Ltd., PVA-205) was prepared. The oil phase component and the aqueous phase component were mixed and emulsified for 10 minutes at 12,000 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 50 ° C. for 3 hours. A microgel (1) was prepared by diluting the solid content concentration of the microgel solution thus obtained with distilled water so as to be 15% by mass. The average particle size of the microgel measured by a laser diffraction / scattering particle size distribution analyzer (LA-920, manufactured by HORIBA, Ltd.) was 0.2 μm.

<Formation of protective layer>
A protective layer coating solution (1) having the following composition was bar coated on the image recording layer, followed by oven drying at 120 ° C. for 60 seconds to form a protective layer having a dry coating amount of 0.15 g / m ² and lithographic printing. An original plate 1 was prepared.

(Coating liquid for protective layer (1))
・ Inorganic layered compound dispersion (1) (below) 1.5 g
-Hydrophilic polymer (1) (the following structure, Mw: 30,000) (solid content) 0.03 g
・ Polyvinyl alcohol (manufactured by Nippon Synthetic Chemical Industry Co., Ltd., CKS50,
Sulfonic acid modification, saponification degree 99 mol% or more, polymerization degree 300)
0.10 g of 6% by weight aqueous solution
・ Polyvinyl alcohol (manufactured by Kuraray Co., Ltd., PVA-405,
Saponification degree 81.5 mol%, polymerization degree 500) 6% by mass aqueous solution 0.03 g
・ Surfactant (Emalex 710, manufactured by Nippon Emulsion Co., Ltd.)
(The following structure) 1 mass% aqueous solution 0.86g
・ Ion-exchanged water 6.0g

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

<Printing using a planographic printing plate dummy>
The lithographic printing plate dummy plate produced as described above is mounted on an offset rotary printing press, and is used as newspaper printing ink by Soiby KKST-S (Red) as ink for printing and Toyo Ink as dampening water. Printing was performed at a speed of 100,000 sheets / hour using Toyo ALKY made by Toyo.

<Evaluation of planographic printing plate dummy>
<Evaluation of color sensor discrimination aptitude>
The above-described planographic printing plate dummy plate, the above-described planographic printing plate precursor 1, hitting ball (Tencolor (orange) manufactured by Shinfuji Paper Co., Ltd.), slip sheet (F slip sheet manufactured by Daiichi Container Co., Ltd.) Was evaluated whether or not the lithographic printing plate dummy and other materials could be distinguished by a color sensor. As the color sensor, a color sensor manufactured by Keyence Corporation (sensor part: CZ-41, amplifier part: CZ-V1) was used. What can be discriminated is indicated as A, and impossible is indicated as B.

<Evaluation of edge dirt prevention performance>
In the above printing process, the 1,000th printed material was sampled, the degree of linear stains at the edge portion was visually observed, and evaluated according to the following criteria. 5 to 3 are acceptable levels. The evaluation results are shown in Table 2.
5: Dirt is not recognized at all.
4: Intermediate level between 5 and 3.
3: Dirt is slightly recognized.
2: Intermediate level between 3 and 1: 1: Dirt is clearly visible.

<Evaluation of on-press developability>
Printing was performed using a lithographic printing plate dummy plate, and in the process, the printed matter on the 50th sheet was sampled after ink supply, the degree of stain was visually observed, and on-machine developability was evaluated according to the following criteria. . 5 to 3 are acceptable levels.
5: Dirt is not recognized at all.
4: Intermediate level between 5 and 3.
3: Dirt is slightly recognized.
2: Intermediate level between 3 and 1: 1: Dirt is clearly visible.

<Evaluation of setter transportability>
A plate was set on a setter Amzi manufactured by NECE, and 50 plates were conveyed. If the conveyance failure was 0 plate, it was evaluated as A, and if it was 1 plate or more, it was evaluated as B.

  From the results shown in Table 17, it was found that the planographic printing plate dummy plate according to the present invention was excellent in edge stain resistance. Further, it was found that it has on-press development suitability and color sensor discrimination suitability. Furthermore, from the results in Table 18, it was found that the lithographic printing plate dummy plate having the matting agent in the second hydrophilic layer also has setter transportability.

1 Planographic printing plate dummy plate 1a Non-photosensitive hydrophilic layer surface 1b Aluminum support surface 1c End surface 2 Sag X Sag amount Y Sag width B Boundary between first hydrophilic layer and aluminum support 10 Cutting blade 10a Upper cutting blade 10b Upper cutting blade 11 Rotating shaft 20 Cutting blade 20a Lower cutting blade 20b Lower cutting blade 21 Rotating shaft 30 Planographic printing plate dummy 41 Aluminum plate 42, 44 Roller brush 43 Polishing slurry liquid 45, 46, 47, 48 Support roller 50 Main electrolysis Tank 51 AC power supply 52 Radial drum roller 53a, 53b Main electrode 54 Electrolyte supply port 55 Electrolyte 56 Slit 58 Auxiliary anode 60 Auxiliary anode tank W Aluminum plate 610 Anodizing device 612 Power supply tank 614 Electrolytic treatment tank 616 Aluminum plate 618, 626 Electrolyte 620 Feed electrode 622, 62 Roller 624 nip roller 630 electrolytic electrode 632 tank wall 634 a DC power source

Claims (15)

Lithographic printing having an aluminum support, a first hydrophilic layer directly formed on the aluminum support, and a second hydrophilic layer directly formed on the first hydrophilic layer in this order A dummy version,
At least one of the first hydrophilic layer and the second hydrophilic layer includes a colorant having an absorption maximum at 350 to 800 nm,
A lithographic printing plate dummy plate, wherein the first hydrophilic layer comprises a polymer compound having a support-adsorbing group and a hydrophilic group.   The lithographic printing plate dummy according to claim 1, wherein the first hydrophilic layer contains the colorant.   The polymer compound has a repeating unit having at least one group selected from the group consisting of a phosphonic acid group, a phosphoric acid group, a carboxylic acid group and a salt thereof as the support adsorptive group, and a sulfone as the hydrophilic group. The lithographic printing plate dummy plate according to claim 1 or 2, which is a polymer compound having an acid group and a salt thereof, an amide group, and a repeating unit having at least one group or structure selected from the group consisting of betaine structures.   The lithographic printing plate dummy according to any one of claims 1 to 3, wherein at least one of the first hydrophilic layer and the second hydrophilic layer contains a hydrophilic compound.   The lithographic printing plate dummy according to any one of claims 1 to 4, wherein at least one of the first hydrophilic layer and the second hydrophilic layer contains fine particles.   The lithographic printing plate dummy according to claim 5, wherein the fine particles are organic resin fine particles.   The lithographic printing plate dummy according to claim 5, wherein the fine particles are microgel. The second hydrophilic layer is selected from hydrophilic polymers having polyvinyl alcohol, carboxymethyl cellulose, and a repeating unit represented by the following general formula (1) and a repeating unit represented by the following general formula (2). The lithographic printing plate dummy plate according to any one of claims 1 to 7, comprising at least one of the above.

In the formula, R ₁ and R ₄ each independently represents a hydrogen atom or a methyl group. R ₂ and R ₃ each independently represents a hydrogen atom, a methyl group, or an ethyl group. R ₅ is a linear, branched or cyclic unsubstituted alkyl group having 2 to 8 carbon atoms, a substituted alkyl group which may have an aromatic ring group or a heterocyclic group as a substituent, or the general formula (3) Represents the substituent represented.
In the general formula (3), L represents an alkylene group having 2 to 6 carbon atoms, and R ₆ represents a linear, branched or cyclic unsubstituted alkyl group having 4 to 8 carbon atoms, or a substituent. A substituted alkyl group having an aromatic group is represented. n is an average added mole number of the polyether and is a number of 2 to 4.   The lithographic printing plate dummy according to any one of claims 1 to 8, wherein the second hydrophilic layer contains a matting agent.   The lithographic printing plate dummy according to claim 9, wherein the matting agent is an organic resin matting agent having a hydrophilic surface.   The lithographic printing plate dummy according to claim 10, wherein the hydrophilic surface comprises silica.   The lithographic printing plate dummy according to any one of claims 1 to 11, wherein the colorant is a water-soluble dye.   The lithographic printing plate dummy according to claim 12, wherein the water-soluble dye is at least one selected from azo dyes, phthalocyanine dyes, anthraquinone dyes, xanthene dyes, indigo dyes, pyranine dyes, and stilbene dyes.   The planographic printing plate dummy plate according to any one of claims 1 to 13, further comprising an on-press development processing step for removing the second hydrophilic layer by supplying at least one of printing ink and dampening water. The printing method used.   The plate-making method of the lithographic printing plate dummy plate of any one of Claims 1-13 including the solution development processing process of removing the said 2nd hydrophilic layer with the developing solution of pH 2-14 containing surfactant. .

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