JP2007190880A - Lithographic printing plate material and lithographic printing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a material for a lithographic printing plate having high sensibility, excellent initial ink-receptivity and plate wear resistance and an excellent ability of recovery from smearing and stains and a lithographic printing method using the material, as well. <P>SOLUTION: The material for the lithographic plate which is provided with a hydrophilic layer on a basic material and an image forming functional layer that can be developed on a printer contains at least a compound selected from the groups represented by any of general formula 1, formula 2, formula 3 and formula 4, in at least one layer on the image forming functional layer side. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a lithographic printing plate material and a lithographic printing method using the same.

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

  In recent years, there is an increasing expectation for a CTP printing plate that does not require a developer treatment with a special agent to reduce the burden on the global environment. Among them, in recent years, after forming an image on a printing plate material with an infrared thermal laser, it can be mounted on a printing machine without being treated with a chemical solution, and can be printed immediately after removing unnecessary portions with dampening water and ink. A printing method using a so-called on-press developable printing plate material (see, for example, Patent Document 1) has attracted attention.

  When these printing plate materials are exposed with an infrared thermal laser, heat is generated by the photothermal conversion material contained in the printing plate material, thereby forming an image. Among them, a printing plate material having a hydrophilic layer containing metal oxide particles as a photothermal conversion material and an image forming functional layer on a base material is preferable as a material that can be developed on a printing press (for example, see Patent Document 2). .

However, in the printing method using the conventional on-press developable printing plate material as described above, the printing sensitivity is low, the initial ink setting property is insufficient, or the printing durability is insufficient. It was something to do. In addition, once the non-image area is soiled, there is a problem that even if dampening water is supplied, the recovery of the soil is poor, that is, the so-called stain recovery property is poor. There has been a strong demand in the market for a printing plate material that solves these problems.
JP 2000-225780 A JP 2004-167773 A

  An object of the present invention is to provide a lithographic printing plate material having high sensitivity and excellent initial ink fillability, printing durability and stain recovery, and a lithographic printing method using the lithographic printing plate material.

  The above object of the present invention is achieved by the following configurations.

  1. In a lithographic printing plate material having a hydrophilic layer on a substrate and an image forming functional layer developable on a printing press, at least one layer on the image forming functional layer side has the following general formulas (1), (2), (3) And a lithographic printing plate material comprising at least one compound selected from (4).

(In the formula, A ₁ and B ₁ represent substituents.)

(In the formula, A ₂ and B ₂ represent substituents.)

(In the formula, R ₁ and R ₂ represent a hydrogen atom or an alkyl group. A ₃ and B ₃ represent the axis of the axis connecting a bond point between the carbon atom shown by C in the general formula and the carbon atom. This represents a group that can completely overlap with the original group when rotated 180 ° around (however, the sum of the hydroxyl groups of A ₃ and B ₃ is 0 or more and 1 or less.)

(In the formula, R ₃ and R ₄ represent a hydrogen atom or an alkyl group. A ₄ and B ₄ represent the axis of the line connecting the carbon atom and the bond point indicated by C in the general formula. Represents a group that can completely overlap with the original group when rotated 180 ° around (provided that the total of hydroxyl groups of A ₄ and B ₄ is from 0 to 1).
2. 2. The lithographic printing plate material as described in 1 above, wherein the image-forming functional layer contains heat-fusible particles or heat-fusible particles.

  3. The lithographic printing plate material according to the above 1 or 2 is image-exposed and then mounted on a printing machine, and dampening water and ink are supplied to the lithographic printing plate material surface to remove non-image areas and printing. Planographic printing method to do.

  According to the present invention, it is possible to provide a lithographic printing plate material having high sensitivity and excellent initial ink fillability, printing durability and stain recovery, and a lithographic printing method using the lithographic printing plate material.

  The present invention relates to a lithographic printing plate material having a hydrophilic layer on a substrate and an image forming functional layer developable on a printing press, wherein at least one layer on the image forming functional layer side has the general formulas (1) and (2 ), (3) and at least one compound selected from (4).

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

  Another preferred embodiment is a compound having the following structure.

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

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

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

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

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

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

  Examples of other preferable compounds are listed below.

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

  These compounds are preferably contained in at least one layer on the image forming functional layer side of the planographic printing plate material of the present invention as a photothermal conversion material.

  As the photothermal conversion material used in the present invention, it is preferable to use a pigment in addition to the compound.

  Examples of the pigment used include carbon, graphite, metal, and metal oxide.

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

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

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

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

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

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

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

  The said metal oxide particle used for this invention is manufactured by the method described in the said open patent gazette. The metal oxide particles according to the present invention are characterized by being safe and harmless to the environment and the human body.

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

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

  Moreover, you may use together infrared absorption pigment | dye other than General formula (1), (2), (3) or (4).

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

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

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

  As addition amount of these photothermal conversion materials, it is 0.1-50 mass% with respect to the layer containing this as a total amount of photothermal conversion materials, 0.5-30 mass% is preferable, 1-25 mass% Is more preferable.

As the photothermal conversion material, the L ^* value in the L ^* a ^* b ^* color system is preferably 0 or more and 13 or less, and more preferably the L ^* value is 0 or more and 10 or less. Here, the “L ^* a ^* b ^* color system” is a color system used to represent the color of an object, which was standardized by the International Commission on Illumination (CIE) in 1976, and is also JIS in Japan. (Z8729). In the L ^* a ^* b ^* color system, lightness is represented by L ^* , and chromaticity indicating hue and saturation is represented by a ^* and b ^* . In the present invention, the L ^* value, which is an index representing brightness, is evaluated as an index of blackness. The smaller the L ^* value, the better the blackness. That is, when the value of L ^* of the black particles is 0 or more and 10 or less, the black particle has sufficient blackness as a photothermal conversion material.

  The photothermal conversion ability with respect to the addition amount of the metal oxide particles according to the present invention is greatly affected by the degree of dispersion of the particles, and the better the dispersion, the better the metal oxide particles according to the present invention are hydrophilic. It is preferable to disperse by a well-known method before adding to the coating liquid of an adhesive layer, and to make it into a dispersion liquid or a paste. A dispersing agent can be used for dispersion as needed. A well-known thing can be used as a dispersing agent. The addition amount of the dispersant is preferably 0.01 to 5% by mass, and more preferably 0.1 to 2% by mass with respect to the pigment particles.

  The average particle size of the metal oxide particles contained in the hydrophilic layer is preferably 1 μm or less, and more preferably in the range of 0.01 to 0.8 μm. When the average particle diameter is 1 μm or less, the photothermal conversion ability with respect to the addition amount becomes better, and when the average primary particle diameter is within the range of 0.01 to 0.8 μm, the photothermal conversion ability with respect to the addition amount is better. It becomes. However, the photothermal conversion ability with respect to the addition amount is greatly affected by the degree of dispersion of the particles, and the better the dispersion, the better. Therefore, it is preferable to disperse these metal oxide particles by a known method separately before adding them to the layer coating solution to prepare a dispersion (paste). An average primary particle size of less than 0.01 μm is not preferable because dispersion becomes difficult.

  The average particle diameter refers to the number average primary particle diameter. The particle diameter is increased 10,000 times by observation with a transmission electron microscope, and the total value obtained by actually measuring the short side and the long side of each of 100 particles is divided by 200. Value.

  The addition amount of the metal oxide particles according to the present invention is 5% by mass or more and less than 80% by mass and 10% by mass or more based on the total solid content of the hydrophilic layer from the viewpoint of sensitivity and prevention of ablation residue. , Less than 70% by mass, more preferably 15% by mass or more and less than 60% by mass.

[Hydrophilic layer]
The hydrophilic layer according to the present invention is a non-image portion that has low affinity for ink and repels ink when the lithographic printing plate material of the present invention is used as a printing plate, and has high affinity for water and retains water. The image forming layer is provided on the hydrophilic layer (on the side opposite to the substrate).

  The hydrophilic layer may consist of a plurality of layers. The metal oxide particles according to the present invention are contained in the hydrophilic layer, and it is particularly preferable that the metal oxide particles are contained in the hydrophilic layer adjacent to the image forming layer.

  The hydrophilic layer according to the present invention preferably has a porous structure. In order to form the hydrophilic layer having the porous structure, hydrophilic materials that form the hydrophilic matrix described below are preferably used.

  As the hydrophilic material forming the hydrophilic matrix, a metal oxide is preferably used. As the metal oxide, the following hydrophilic materials are preferably used. However, the metal oxide particles used as the photothermal conversion material may partially serve as a hydrophilic material.

(Metal oxide)
The metal oxide preferably contains metal oxide particles, and examples thereof include colloidal silica, alumina sol, titania sol, and other metal oxide sols. The form of the metal oxide fine particles may be spherical, needle-like, feather-like, or any other form. The average particle diameter is preferably in the range of 3 to 100 nm, and several kinds of metal oxide particles having different average particle diameters. Can also be used together. Further, the surface of the particles may be subjected to a surface treatment.

  The metal oxide particles can be used as a binder by utilizing the film forming property. The decrease in hydrophilicity is less than when an organic binder is used, and it is suitable for use in a hydrophilic layer.

(Colloidal silica)
Among these, colloidal silica can be particularly preferably used. Colloidal silica has the advantage of high film-forming properties even under relatively low temperature drying conditions, and can provide good strength. The colloidal silica preferably includes a necklace-like colloidal silica, which will be described later, and a fine particle colloidal silica having an average particle size of 20 nm or less. Further, the colloidal silica preferably exhibits alkalinity when used as a colloidal solution.

  Necklace-shaped colloidal silica is a general term for an aqueous dispersion of spherical silica whose primary particle diameter is of the order of nm, and spherical colloidal silica having a primary particle diameter of 10 to 50 nm bonded to a length of 50 to 400 nm. It means colloidal silica in the form of “pearl necklace”. A pearl necklace shape (that is, a pearl necklace shape) means that an image in a state in which silica particles of colloidal silica are connected and connected has a shape like a pearl necklace.

  The bond between the silica particles constituting the necklace-shaped colloidal silica is presumed to be —Si—O—Si— in which —SiOH groups present on the surface of the silica particles are dehydrated. Specific examples of the colloidal silica in the form of necklace include “Snowtex-PS” series manufactured by Nissan Chemical Industries, Ltd., and the product name is “Snowtex-PS-S” 110 ")," Snowtex-PS-M (average particle size in the connected state is about 120 nm) "and" Snowtex-PS-L (average particle size in the connected state is about 170 nm) " Acidic products corresponding to the above are "Snowtex-PS-SO", "Snowtex-PS-MO" and "Snowtex-PS-LO".

  By adding necklace-like colloidal silica, it becomes possible to maintain the strength while ensuring the porosity of the layer, and it can be preferably used as a porous material for the hydrophilic layer matrix. Among these, alkaline “Snowtex PS-S”, “Snowtex PS-M” and “Snowtex PS-L” improve the strength of the hydrophilic layer, and even when the number of printed sheets is large, The occurrence of dirt is suppressed, which is particularly preferable.

  Further, it is known that the colloidal silica has a stronger binding force as the particle diameter is smaller. In the present invention, it is preferable to use colloidal silica having an average particle diameter of 20 nm or less, more preferably 3 to 15 nm. is there.

  As described above, among the colloidal silica, an alkaline one is particularly preferable because it has an effect of suppressing the occurrence of soiling. Examples of the alkaline colloidal silica having an average particle diameter in this range include, for example, “Snowtex-20 (particle diameter 10-20 nm)”, “Snowtex-30 (particle diameter 10-20 nm)” manufactured by Nissan Chemical Co., Ltd. “Snowtex-40 (particle diameter 10-20 nm)”, “Snowtex-N (particle diameter 10-20 nm)”, “Snowtex-S (particle diameter 8-11 nm)”, “Snowtex-XS (particle diameter) 4-6 nm) ".

  Colloidal silica having an average particle size of 20 nm or less is particularly preferred because it can be further improved in strength while maintaining the porosity of the layer to be formed, when used in combination with the aforementioned necklace-like colloidal silica.

  The ratio of colloidal silica / necklace-shaped colloidal silica having an average particle diameter of 20 nm or less is preferably in the range of 95/5 to 5/95, more preferably in the range of 70/30 to 20/80, and more preferably in the range of 60/40 to A range of 30/70 is more preferred.

  In the present invention, porous metal oxide particles having a particle size of less than 1 μm can be contained as a porous material having a hydrophilic layer matrix structure.

(Porous metal oxide particles)
As the porous metal oxide particles, the following porous silica particles, porous aluminosilicate particles, or zeolite particles can be preferably used.

(Porous silica particles, porous aluminosilicate particles)
The porous silica particles are generally produced by a wet method or a dry method. In the wet method, the gel obtained by neutralizing the aqueous silicate solution can be obtained by drying and pulverizing, or by pulverizing the precipitate deposited by neutralization. In the dry method, silicon tetrachloride is burned together with hydrogen and oxygen to obtain silica. These particles can be controlled in their porosity and particle size by adjusting the production conditions. As the porous silica particles, those obtained from a wet gel are particularly preferable.

  The porous aluminosilicate particles are produced, for example, by the method described in JP-A-10-71764. That is, amorphous composite particles synthesized by hydrolysis using aluminum alkoxide and silicon alkoxide as main components. The ratio of alumina to silica in the particles can be synthesized in the range of 1: 4 to 4: 1. Moreover, what was manufactured as composite particle | grains of 3 or more components by adding the alkoxide of another metal at the time of manufacture can be used for this invention. These composite particles can also control the porosity and particle size by adjusting the production conditions.

  The porosity of the particles is preferably 0.5 ml / g or more in terms of pore volume, more preferably 0.8 ml / g or more, and further preferably 1.0 to 2.5 ml / g. preferable.

(Zeolite particles)
Zeolite is a crystalline aluminosilicate and is a porous body having regular three-dimensional network voids having a pore diameter of 0.3 to 1 nm.

  Moreover, the hydrophilic layer matrix structure which comprises a hydrophilic layer can contain a layered mineral particle.

  Examples of the layered mineral particles include kaolinite, halloysite, talc, smectite (montmorillonite, beidellite, hectorite, sabonite, etc.), clay minerals such as vermiculite, mica (mica), chlorite, hydrotalcite, layered polysilicic acid. Examples thereof include salts (kanemite, macatite, ialite, magadiite, kenyaite, etc.). In particular, the higher the charge density of the unit layer (unit layer), the higher the polarity and the higher the hydrophilicity. The charge density is preferably 0.25 or more, more preferably 0.6 or more. Examples of the layered mineral having such a charge density include smectite (charge density 0.25 to 0.6; negative charge), vermiculite (charge density 0.6 to 0.9; negative charge) and the like. In particular, synthetic fluoromica is preferable because it can be obtained with stable quality such as particle size. Further, among the synthetic fluorine mica, those that are swellable are preferable, and those that are free swell are more preferable.

  Also used are intercalation compounds of the above-mentioned layered minerals (pillar crystals, etc.), those subjected to ion exchange treatment, and those subjected to surface treatment (silane coupling treatment, compounding treatment with organic binder, etc.) can do.

  As for the size of the layered mineral particles, the average particle size (maximum length of the particles) is less than 1 μm, and the average aspect ratio is contained in the layer (including the case of undergoing the swelling process and dispersion peeling process). Is preferably 50 or more. When the particle size is in the above range, the continuity and flexibility in the planar direction, which are the characteristics of the thin layered particles, are imparted to the coating film, and it is difficult for cracks to occur, and a tough coating film can be obtained in a dry state. Moreover, in the coating liquid containing many particulate matters, sedimentation of particulate matter can be suppressed by the thickening effect of the layered clay mineral. When the particle diameter is larger than the above range, the coating film may be non-uniform, and the strength may be locally reduced. Further, when the aspect ratio is not more than the above range, the number of tabular grains with respect to the addition amount is reduced, the viscosity is insufficient, and the effect of suppressing the sedimentation of the particulate matter is reduced.

  The content of the layered mineral particles is preferably 0.1 to 30% by mass, and more preferably 1 to 10% by mass based on the entire layer. In particular, swellable synthetic fluorinated mica and smectite are preferable because they can be effective even when added in a small amount. The layered mineral particles may be added in powder form to the coating solution, but in order to obtain a good degree of dispersion even with a simple preparation method (no need for a dispersion step such as media dispersion), the layered mineral particles are used alone. It is preferable to prepare a gel swollen in water and then add it to the coating solution.

For the hydrophilic layer matrix constituting the hydrophilic layer, an aqueous silicate solution can also be used as another additive material. Alkali metal silicates such as silicate Na, silicate K, and silicate Li are preferred, and the SiO ₂ / M ₂ O ratio is in a range where the pH of the entire coating solution does not exceed 13 when silicate is added. It is preferable to select such that the inorganic particles are not dissolved.

  In addition, an inorganic polymer or an organic-inorganic hybrid polymer by a so-called sol-gel method using a metal alkoxide can also be used. The formation of an inorganic polymer or an organic-inorganic hybrid polymer by the sol-gel method is described in, for example, “Application of the sol-gel method” (Sakuo Sakuo / Agne Jofusha) or in this book Known methods described in the cited documents can be used.

  The hydrophilic layer may contain a water-soluble resin.

  Examples of water-soluble resins include polysaccharides, polyethylene oxide, polypropylene oxide, polyvinyl alcohol, polyethylene glycol (PEG), polyvinyl ether, styrene-butadiene copolymer, and conjugated diene polymer latex of methyl methacrylate-butadiene copolymer. Examples thereof include resins such as acrylic polymer latex, vinyl polymer latex, polyacrylamide, and polyvinylpyrrolidone. As the water-soluble resin used in the present invention, it is preferable to use a polysaccharide.

  As polysaccharides, starches, celluloses, polyuronic acids, pullulans and the like can be used, but cellulose derivatives such as methyl cellulose salts, carboxymethyl cellulose salts, hydroxyethyl cellulose salts are particularly preferable, and sodium salts and ammonium salts of carboxymethyl cellulose are preferable. More preferred. This is because an effect of forming the surface shape of the hydrophilic layer in a preferable state can be obtained by including the polysaccharide in the hydrophilic layer.

  The surface of the hydrophilic layer preferably has a concavo-convex structure with a pitch of 0.1 to 20 μm like the aluminum grain of the PS plate, and this concavo-convex improves water retention and image area retention. Such a concavo-convex structure can be formed by adding an appropriate amount of a filler having an appropriate particle size to the hydrophilic layer matrix. However, the above-mentioned alkaline colloidal silica and the above-mentioned water-soluble solution are added to the hydrophilic layer coating solution. In order to obtain a structure having better printability, it is preferable to form a phase separation when the hydrophilic polysaccharide is applied and dried.

  The shape of the concavo-convex structure (pitch, surface roughness, etc.) is determined depending on the type and amount of alkaline colloidal silica, the type and amount of water-soluble polysaccharides, the type and amount of other additives, the solid content concentration of the coating solution, and the wetness. It is possible to appropriately control the film thickness, drying conditions, and the like.

  The water-soluble resin added to the hydrophilic matrix structure part is preferably present in a state where at least a part thereof is water-soluble and can be eluted in water. This is because even a water-soluble material is crosslinked by a crosslinking agent or the like and becomes insoluble in water, so that its hydrophilicity is lowered and printability may be deteriorated. Further, it may further contain a cationic resin. Examples of the cationic resin include polyalkylene polyamines such as polyethylene amine and polypropylene polyamine or derivatives thereof, tertiary amino groups and quaternary ammonium groups. Examples thereof include acrylic resin and diacrylamine. The cationic resin may be added in the form of fine particles, and examples thereof include a cationic microgel described in JP-A-6-161101.

  In order to provide the hydrophilic layer according to the present invention, it is preferable to form the layer by coating and drying using a coating solution for the hydrophilic layer. As described above, in order to include the metal oxide particles according to the present invention in the coating solution for the hydrophilic layer, the metal oxide particles are dispersed by a known method before adding the metal oxide particles to form a dispersion or paste. It is preferable to add to the coating solution for the hydrophilic layer.

  The coating solution used to coat the hydrophilic layer can contain a water-soluble surfactant for the purpose of improving coating properties, and use a surfactant such as Si or F. However, it is preferable to use a surfactant containing Si element because there is no fear of causing printing stains. The content of the surfactant is preferably 0.01 to 3% by mass, more preferably 0.03 to 1% by mass, based on the entire hydrophilic layer (solid content as the coating solution).

  The hydrophilic layer can contain a phosphate. In the present invention, since the hydrophilic layer coating solution is preferably alkaline, the phosphate is preferably added as trisodium phosphate or disodium hydrogen phosphate. By adding phosphate, the effect of improving the mesh opening during printing can be obtained. The addition amount of phosphate is preferably 0.1 to 5% by mass, and more preferably 0.5 to 2% by mass as an effective amount excluding hydrate.

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

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

  As the image forming functional layer according to the present invention, an image forming functional layer containing heat fusible particles or heat fusible particles is preferable.

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

(Water-soluble binder)
The image forming functional layer may contain a water-soluble binder. Examples of the water-soluble binder include polysaccharides, polyethylene oxide, polypropylene oxide, polyvinyl alcohol, polyethylene glycol (PEG), polyvinyl ether, and styrene-butadiene copolymers. Examples thereof include conjugated diene polymer latex of methyl methacrylate-butadiene copolymer, acrylic polymer latex, vinyl polymer latex, polyacrylamide, polyacrylic acid or salts thereof, and resins such as polyvinylpyrrolidone.

  Among them, it is preferable to use polyacrylic acid or a salt or polysaccharide thereof that does not deteriorate the printing performance.

Moreover, the photothermal conversion raw material mentioned above can be contained. The dry coating mass of the image forming functional layer is preferably 0.1 to 1.5 g / m ² , more preferably 0.15 to 1.0 g / m ² .

〔Base material〕
As a base material which concerns on this invention, the well-known base material used for the conventional printing plate material can be used.

  The thickness of the base material is not particularly limited as long as it can be attached to a printing press, but a thickness of 50 to 500 μm is generally easy to handle.

  Examples of the substrate include a metal plate, a plastic film, paper treated with polyolefin, a composite support obtained by appropriately bonding the above materials, etc. In the present invention, in particular, a plastic film and aluminum or an aluminum alloy A metal plate (hereinafter referred to as aluminum) is preferably used.

  Examples of the plastic film include films of polyethylene terephthalate, polyethylene naphthalate, polyimide, polyamide, polycarbonate, polysulfone, polyphenylene oxide, cellulose esters, and the like.

  In the present invention, among these plastic films, polyester films such as polyethylene terephthalate (hereinafter sometimes abbreviated as PET) and polyethylene naphthalate (hereinafter sometimes abbreviated as PEN) are preferably used as the base material. .

  Furthermore, it is preferable to use a support obtained by the method described in JP-A-10-10676 and having a thermal dimensional change rate at 120 ° C. for 30 seconds of 0.001% to 0.04%.

  A preferable polyester film is an unstretched polyester film, a uniaxially stretched polyester film, or a biaxially stretched polyester film.

  Of these, a longitudinally stretched polyester film uniaxially stretched in the film extrusion direction (longitudinal direction) is particularly preferred.

  PET is polymerized with terephthalic acid and ethylene glycol, and PEN polymerized with naphthalenedicarboxylic acid and ethylene glycol as constituent components.

  The dicarboxylic acid or diol constituting PET or PEN may be polymerized by mixing other appropriate one type or two or more third components. A suitable third component is a compound having a divalent ester-forming functional group. Examples of the dicarboxylic acid include the following.

  Terephthalic acid, isophthalic acid, phthalic acid, 2,6-naphthalenedicarboxylic acid, 2,7-naphthalenedicarboxylic acid, diphenylsulfone dicarboxylic acid, diphenylether dicarboxylic acid, diphenylethanedicarboxylic acid, cyclohexanedicarboxylic acid, diphenyldicarboxylic acid, diphenylthioether dicarboxylic acid Examples thereof include acid, diphenyl ketone dicarboxylic acid, and phenylindane dicarboxylic acid.

  Examples of glycols include propylene glycol, tetramethylene glycol, cyclohexanedimethanol, 2,2-bis (4-hydroxyphenyl) propane, 2,2-bis (4-hydroxyethoxyphenyl) propane, and bis (4- Hydroxyphenyl) sulfone, bisphenol full orange hydroxyethyl ether, diethylene glycol, neopentyl glycol, hydroquinone, cyclohexanediol and the like.

  As the third component, a polyfunctional carboxylic acid or a polyhydric alcohol can also be mixed, but these can be mixed in an amount of about 0.001 to 5% by mass with respect to all the polyester components.

  The intrinsic viscosity of the polyester film is preferably 0.5 to 0.8. Moreover, you may mix and use what has a different intrinsic viscosity.

  The polymerization method of the polyester film is not particularly limited, and can be produced according to a conventionally known polyester polymerization method. For example, a direct ester is obtained by directly esterifying a dicarboxylic acid component with a diol component, diesterifying one hydroxyl group of the diol to a dicarboxylic acid, and heating the other diol under reduced pressure to distill off the excess diol. A dialkyl ester (for example, dimethyl ester) as a dicarboxylic acid component, and a transesterification reaction between this and a diol component to distill alkyl alcohol (for example, methanol) to distill one hydroxyl group of the diol to a dicarboxylic acid. It is possible to use a transesterification method in which polymerization is performed by esterification into an acid and further heating and distilling off excess diol components under reduced pressure.

As the catalyst, a transesterification catalyst, a polymerization reaction catalyst, and a heat stabilizer used for synthesis of a normal polyester can be used. Examples of transesterification catalysts include Ca (OAc) ₂ .H ₂ O, Zn (OAc) ₂ .2H ₂ O, Mn (OAc) ₂ .4H ₂ O, Mg (OAc) ₂ .4H ₂ O, and the like. Examples of the polymerization reaction catalyst include Sb ₂ O ₃ and GeO ₂ . Examples of the heat stabilizer include phosphoric acid, phosphorous acid, PO (OH) (CH ₃ ) ₃ , PO (OC ₆ H ₅ ) ₃ , P (OC ₆ H ₅ ) _{3 and the} like. In addition, anti-coloring agent, crystal nucleating agent, slip agent, stabilizer, anti-blocking agent, UV absorber, viscosity modifier, clearing agent, antistatic agent, pH adjuster, dye, pigment, etc. May be added.

  In order to stabilize the dimensions during printing and prevent color misregistration during color printing, it is preferable to heat-treat the polyester film after stretching and heat setting.

  The heat treatment is preferably accomplished by the following means after cooling and winding after completion of heat setting and then unwinding in a separate step.

  As a heat treatment method, a transport method in which both ends of a film such as a tenter are gripped with pins or clips, a roll transport method using a plurality of roll groups, a method of transporting air by blowing air on the film, etc. A method in which heated air is blown from one side or both sides of a film surface through a slit), a method using radiant heat by an infrared heater, a method in which a plurality of heated rolls are brought into contact with each other, a method in which heat treatment is performed alone or in combination, and a film is self-weighted. It is preferable to use one or a combination of a plurality of conveying methods such as winding in the lower part.

  The tension of the heat treatment can be adjusted by adjusting the torque of the take-up roll and / or the delivery roll, and / or by installing a dancer roll in the process and adjusting the load applied to the dancer roll.

  When changing the tension during the heat treatment and / or cooling after the heat treatment, a desired tension state may be set by installing dancer rolls before and after these processes and / or in the processes and adjusting their loads. . In addition, it is possible to effectively change the conveyance tension by vibration by reducing the span between the heat treatment rolls.

  In order to reduce the dimensional change during the subsequent heat treatment (heat development) without hindering the progress of the heat shrinkage, it is desirable to make the conveyance tension as low as possible and lengthen the heat treatment time.

  The treatment temperature is preferably a temperature range of Tg + 50 ° C. to Tg + 150 ° C. of the polyester film, and the transport tension in that temperature range is preferably 5 Pa to 1 MPa, more preferably 5 Pa to 500 kPa, still more preferably 5 Pa to 200 kPa, and the treatment time. Is preferably 30 seconds to 30 minutes, more preferably 30 seconds to 15 minutes. By using the above temperature range, conveyance tension range, and processing time, the flatness of the support does not deteriorate due to a partial difference in thermal shrinkage of the support during heat treatment, and fine scratches due to friction with the transfer roll, etc. Etc. can also be suppressed.

  The heat treatment is preferably performed at least once in order to obtain a desired dimensional change rate, and may be performed twice or more as necessary.

  In order to prevent the deterioration of flatness due to cooling at this time, the heat-treated polyester film is cooled from a temperature near Tg to room temperature, and at least −5 ° C./second or more until it is lowered to room temperature across Tg. It is preferable to cool with.

  In the case of a polyester film base material, the water content of the base material is preferably 0.5% by mass or less in order to satisfactorily carry in an exposure apparatus or the like. The moisture content of the substrate is D ′ represented by the following formula.

D ′ (mass%) = (w ′ / W ′) × 100
In the formula, W ′ is the mass of the support in a humidity control equilibrium under an atmosphere of 25 ° C. and 60% relative humidity, and w ′ is the moisture content of the support in a humidity control equilibrium under an atmosphere of 25 ° C. and 60% relative humidity. Represents content.

  The water content of the substrate is preferably 0.5% by mass or less, more preferably 0.01 to 0.5% by mass, and particularly preferably 0.01 to 0.3% by mass.

  As means for controlling the moisture content of the substrate to 0.5% by mass or less, (1) the support is heat-treated at 100 ° C. or more immediately before applying the coating liquid for the hydrophilic layer and other layers, (2) Control the relative humidity in the step of applying the coating solution for the hydrophilic layer and other layers. (3) Before applying the coating solution for the hydrophilic layer and other layers, heat-treat the support at 100 ° C. or higher to prevent moisture. Cover and store with a sheet, and apply immediately after opening. Two or more of these may be combined.

(Fine particles)
It is preferable to add 0.01 to 10 μm of particles of 0.01 to 10 μm in the polyester base material in order to improve handling properties.

  These particles may be either organic or inorganic. Examples of inorganic substances include silica described in Swiss Patent No. 330,158 and the like, glass powder described in French Patent No. 1,296,995, and British Patent No. 1,173,181. Alkaline earth metals or carbonates such as cadmium and zinc described in the book can be used. Examples of organic substances include starch described in US Pat. No. 2,322,037 and the like, starch derivatives described in Belgian Patent 625,451 and British Patent 981,198, and the like. No. 44-3643 etc., polyvinyl alcohol described in Swiss Patent No. 330,158, etc., polystyrene or polymethacrylate described in US Pat. No. 3,079,257, etc., polyacrylonitrile described in US Pat. Organic fine particles such as polycarbonate described in Japanese Patent No. 3,022,169 can be used. The shape of the particles may be either regular or irregular.

(Applying undercoat layer to substrate)
In the polyester film base material, easy adhesion treatment or undercoat layer coating can be performed in order to have various functions.

  Examples of the easy adhesion treatment include corona discharge treatment, flame treatment, plasma treatment, and ultraviolet irradiation treatment.

  As the undercoat layer, a layer containing gelatin or latex is preferably provided on the polyester film support. Among them, the antistatic undercoat layer described in JP-A-7-191433, paragraph numbers 0044 to 0116 is preferably used. Further, a conductive layer such as a conductive polymer-containing layer described in paragraph Nos. 0031 to 0073 of JP-A-7-20596 or a metal oxide-containing layer described in paragraph Nos. 0074 to 0081 of JP-A-7-20596 is provided. It is preferable. The conductive layer may be coated on either side as long as it is on the polyester film support, but it is preferably coated on the opposite side of the image forming functional layer with respect to the support. When this conductive layer is provided, the chargeability is improved, the adhesion of dust and the like is reduced, and white spots failure during printing is greatly reduced.

(Aluminum metal plate base material)
The aluminum metal plate is preferably used after being subjected to roughening treatment, anodizing treatment or the like in order to form a hydrophilic surface. The aluminum metal plate is preferably subjected to a degreasing treatment in order to remove the rolling oil on the aluminum surface prior to the roughening treatment. As the degreasing treatment, a degreasing treatment using a solvent such as trichlene or thinner, an emulsion degreasing treatment using an emulsion such as kesilon or triethanol, or the like is used. In addition, an alkaline aqueous solution such as sodium hydroxide, potassium hydroxide, sodium carbonate, sodium phosphate or the like can also be used for the degreasing treatment. When an alkaline aqueous solution is used for the degreasing treatment, dirt and oxide film that cannot be removed only by the degreasing treatment can be removed.

  The roughening of the substrate can be performed by chemical roughening treatment, mechanical roughening, or roughening treatment appropriately combining them. Following the roughening treatment, it is preferable to perform an anodizing treatment.

  There is no restriction | limiting in particular in the method of an anodizing process, A well-known method can be used. The anodized base material may be subjected to a sealing treatment as necessary. These sealing treatments can be performed using known methods such as hot water treatment, boiling water treatment, water vapor treatment, dichromate aqueous solution treatment, nitrite treatment, ammonium acetate treatment.

  Further, the anodized base material can be appropriately subjected to a surface treatment other than the sealing treatment. Examples of the surface treatment include known treatments such as silicate treatment, phosphate treatment, various organic acid treatments, PVPA treatment, and boehmite treatment. In addition, an organic acid treatment such as citric acid may be performed following the treatment with an aqueous solution containing a bicarbonate described in JP-A-8-314157 or the treatment with an aqueous solution containing a bicarbonate.

  Moreover, in order to improve adhesiveness with a coating layer, it is preferable to perform an easily bonding process and undercoat layer application | coating to an application surface. For example, a method of dipping in a liquid containing a coupling agent such as a silicate or a silane coupling agent, or applying a liquid and then sufficiently drying may be mentioned.

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

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

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

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

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

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

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

  The step of removing the non-image portion of the image forming functional layer according to the present invention can be performed by a normal printing sequence using a PS plate, and is preferably a step performed by so-called on-press development processing. It is an aspect.

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

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

  EXAMPLES Hereinafter, the present invention will be specifically described with reference to examples, but the present invention is not limited thereto. In the examples, “parts” means “parts by mass” unless otherwise specified.

[Preparation of substrate 1]
(PET resin)
0.05 parts by mass of magnesium acetate hydrate was added as a transesterification catalyst to 100 parts by mass of dimethyl terephthalate and 65 parts by mass of ethylene glycol, and transesterification was performed according to a conventional method. To the obtained product, 0.05 part by weight of antimony trioxide and 0.03 part by weight of trimethyl phosphate were added. Subsequently, the temperature was gradually raised and reduced, and polymerization was carried out at 280 ° C. and 66 Pa to obtain a polyethylene terephthalate (PET) resin having an intrinsic viscosity of 0.70.

  Using the PET resin obtained as described above, a biaxially stretched PET film was prepared as follows.

(Biaxially stretched PET film)
Pelletized PET resin is vacuum-dried at 150 ° C for 8 hours, melted and extruded from a T-die at 285 ° C in a layered form, closely contacted with electrostatic application on a cooling drum at 30 ° C, cooled and solidified, and unstretched A film was obtained.

  This unstretched sheet was stretched 3.3 times in the longitudinal direction at 80 ° C. using a roll type longitudinal stretching machine. Subsequent to the obtained uniaxially stretched film, using a tenter-type lateral stretching machine, the film was stretched by 50% of the total transverse stretching ratio in the first stretching zone at 90 ° C., and further at the total stretching ratio of 3.3 in the second stretching zone at 100 ° C. Stretched to double.

  Subsequently, pre-heat treatment was performed at 70 ° C. for 2 seconds, and heat setting was further performed at the first fixing zone 150 ° C. for 5 seconds, and heat fixing was performed at the second fixing zone 220 ° C. for 15 seconds. Next, 5% relaxation treatment was performed in the transverse (width) direction at 160 ° C., and after exiting the tenter, it was cooled to room temperature over 60 seconds. The film was released from the clip, slitted, wound up, and 175 μm thick biaxial A stretched PET film was obtained. The biaxially stretched PET film had a Tg of 79 ° C. In addition, the thickness distribution of the obtained base material was 2%.

One side surface of the biaxially stretched PET film is subjected to a corona discharge treatment of 8 W / m ² · min, and the undercoat coating solution a-1 is applied to a dry film thickness of 0.8 μm, dried at 123 ° C., A pulling layer A-1 was provided. Thereafter, the upper surface of the undercoat layer A-1 is subjected to a corona discharge treatment of 8 W / m ² · min, and the undercoat coating liquid a-2 is dried on the undercoat layer A-1 with a dry film thickness of 0. The resultant was applied to 1 μm, dried at 123 ° C. to provide an undercoat layer A-2, and further heat-treated at 140 ° C. for 2 minutes (undercoat surface A).

Further, the opposite surface was subjected to corona discharge treatment under the condition of 10 W / m ² · min, and the following undercoat coating solution c-1 was applied to a dry film thickness of 0.06 μm and dried at 140 ° C. Subsequently, the following undercoat coating solution d-1 was applied so as to have a dry film thickness of 0.2 μm, and then dried at 140 ° C. (undercoat surface B). In this way, the base material 1 with the double-sided undercoat layer formed was obtained.

(Undercoat coating liquid a-1)
Styrene / glycidyl methacrylate / butyl acrylate = 60/39/1 (molar ratio) terpolymer copolymer latex (Tg = 75 ° C.) solid content concentration 30% by mass 250 g
Styrene / glycidyl methacrylate / butyl acrylate = 20/40/40 (molar ratio) terpolymer copolymer latex (Tg = 20 ° C.) solid content concentration 30% by mass 25 g
Anionic surfactant S-1 (2% by mass) 30 g
Finished to 1 kg with water.

(Undercoat coating liquid a-2)
Modified aqueous polyester L-4 solution (23% by mass) 31 g
58 g of 5% aqueous solution of Kuraray Exebar (copolymer of polyvinyl alcohol and ethylene) RS-2117
Anionic surfactant S-1 (2% by mass) 6 g
Hardener H-1 (0.5% by mass) 100 g
True spherical silica matting agent (Seahoster KE-P50 made by Nippon Shokubai) 2% by mass dispersion
10g
Distilled water was added to make 1000 ml.

(Preparation of aqueous polyester solution A1)
35.4 parts by weight of dimethyl terephthalate, 33.63 parts by weight of dimethyl isophthalate, 17.92 parts by weight of dimethyl sodium 5-sulfoisophthalate, 62 parts by weight of ethylene glycol, 0.065 parts by weight of calcium acetate monohydrate, acetic acid After transesterification of 0.022 parts by mass of manganese tetrahydrate under a nitrogen stream while distilling off methanol at 170 to 220 ° C., 0.04 parts by mass of trimethyl phosphate and trioxide as a polycondensation catalyst 0.04 parts by mass of antimony and 6.8 parts by mass of 1,4-cyclohexanedicarboxylic acid were added, and an approximately theoretical amount of water was distilled off at a reaction temperature of 220 to 235 ° C. to perform esterification.

  Thereafter, the reaction system was further depressurized and heated for about 1 hour, and finally subjected to polycondensation at 280 ° C. and 133 Pa or less for about 1 hour to prepare an aqueous polyester.

  The obtained aqueous polyester had an intrinsic viscosity of 0.33 (100 ml / g). Moreover, the weight average molecular weight was 80,000-100,000.

  Next, 850 ml of pure water was placed in a 2 L three-necked flask equipped with a stirring blade, a reflux condenser, and a thermometer, and 150 g of aqueous polyester was gradually added while rotating the stirring blade.

  After stirring for 30 minutes at room temperature, the mixture was heated to an internal temperature of 98 ° C. over 1.5 hours and dissolved at this temperature for 3 hours. After completion of the heating, the mixture was cooled to room temperature over 1 hour and allowed to stand overnight to prepare a 15% by mass aqueous polyester solution A1.

<< Preparation of Modified Aqueous Polyester L-4 Solution >>
Into a 3 L four-necked flask equipped with a stirring blade, a reflux condenser, a thermometer, and a dropping funnel, 1900 ml of the 15% by weight aqueous polyester solution A1 is placed, and the internal temperature is increased to 80 ° C. while rotating the stirring blade. Heat.

  Into this, 6.52 ml of a 24% aqueous solution of ammonium peroxide was added, and a monomer mixture (28.5 g of glycidyl methacrylate, 21.4 g of ethyl acrylate, 21.4 g of methyl methacrylate) was dropped over 30 minutes, The reaction is continued for another 3 hours.

  Then, it cooled and filtered to 30 degrees C or less, and prepared the modified aqueous polyester B1 solution (vinyl component modification ratio 20 mass%) whose solid content concentration is 18 mass%. Moreover, what made the vinyl-type component modification | denaturation ratio 5 mass% was set as modified | denatured aqueous polyester L-4.

(Undercoat coating liquid c-1; containing conductive compound)
Copolymer polymer latex of styrene / glycidyl methacrylate / butyl acrylate (20/40/40) (solid content 30%) 16.0 g
Copolymer polymer latex of styrene / butyl acrylate / hydroxymethyl methacrylate (25/45/30) (solid content 30%) 4.0 g
SnO ₂ sol (solid content 10%) (synthesized by the method described in Example 1 of JP-A-10-059720) 9.1 g
Anionic surfactant S-1 0.5g
Distilled water was added to make 1000 ml of the coating solution.

(Undercoat coating liquid d-1)
Modified polyester A (solid content 18%) 215.0 g
Anionic surfactant S-1 0.4 g
Spherical silica Seahoster KE-P50 (Nippon Shokubai Co., Ltd.) 0.3g
Distilled water was added to make 1000 ml, and a coating solution having a solid content concentration of 0.5% was obtained.

<Modified polyester A>
Water dispersion of water-soluble copolyester component / acrylic component (80/20). The water-soluble copolyester component is a mixed component of terephthalic acid / isophthalic acid / cyclohexanedicarboxylic acid / 5-sulfo-isophthalic acid dimethyl sodium salt (40/38/14/8) and ethylene glycol, and the acrylic component is methyl methacrylate. Copolymer latex of / ethyl acrylate / glycidyl methacrylate (53/37/10).

[Production of substrate 2 (aluminum substrate)]
An aluminum plate (AA1050) having a thickness of 0.24 mm was degreased using an aqueous sodium hydroxide solution. The amount of aluminum dissolved was 2 g / m ² . After sufficiently washing with pure water, it was immersed in a 1% by mass disodium hydrogen phosphate aqueous solution at 70 ° C. for 30 seconds. Next, the substrate 2 was obtained by thoroughly washing with pure water and drying.

[Preparation of coating solution for back coating layer]
Colloidal silica: Snowtex-XS (manufactured by Nissan Chemical, solid content 20% by mass)
33.60 parts by mass Acrylic emulsion: DK-05 (Gifu Shellac, solid content 48% by mass)
14.00 parts by weight Matting agent (PMMA average particle size 5.5 μm) 0.56 parts by weight Pure water 51.84 parts by weight Solid content concentration 14% by weight
These compositions were sufficiently stirred and mixed using a homogenizer, and then filtered to prepare a back coating layer coating solution.

(Application of back coating layer)
The coating solution for the back coating layer is subjected to a corona discharge treatment of 8 W / m ² / min on the undercoating surface B of the base material 1 and applied to the undercooked sample using the wire bar # 6. The drying zone set at 100 ° C. was passed at a conveyance speed of 15 m / min. The amount of the back coating layer was 2.0 g / m ² .

[Lower hydrophilic layer coating solution]
The composition shown in Table 1 was sufficiently stirred and mixed using a homogenizer, and then filtered to prepare a lower hydrophilic layer coating solution.

[Upper hydrophilic layer coating solution]
The composition shown in Table 2 was sufficiently stirred and mixed using a homogenizer, and then filtered to prepare an upper hydrophilic layer coating solution.

  The metal oxide dispersion used for the lower hydrophilic layer and the upper hydrophilic layer is placed in a sand grinder with the following dispersion composition together with steel beads having a diameter of 1.5 mm, and dispersed for 2.5 hours at a rotational speed of 1500 rpm. did. After dispersion, the finished amount was made 200 g with pure water. The coercive force (HC) was 800 A / m when HC was measured in a magnetic field of 400 kA / m using a vibrating sample magnetometer VSM-P7-15 manufactured by Toei Industry Co., Ltd.

(Dispersion composition)
Metal oxide particles 59.6g
Na ₃ PO ₄ (10% aqueous solution) 4 g
116.4g of pure water
Metal oxide particles: Metal oxide particles OS-1 having TiO ₂ (rutile titanium oxide) with an average particle size of 0.22 μm and an Fe ₂ TiO ₄ phase as main components are used.

(Manufacturing method of OS-1)
A hydrous titanium oxide slurry having a specific surface area of 260 m ² / g obtained by the sulfuric acid method is prepared as titanium oxide to 150 g / L, and the pH is neutralized to 9 using 400 g / L of caustic soda. After stirring for 2 hours, the pH was adjusted to 6 with 200 g / L hydrochloric acid, and filtration washes were performed. The hydrous titanium oxide that has been washed is repulped, adjusted to 100 g / L as titanium oxide, and then 100 g / L of ferric chloride solution as Fe ₂ O _{3 is used} as the slurry. After the addition, 200 g / L of caustic soda solution was added dropwise to adjust the pH of the slurry to 7, and the surface of the water-containing / titanium oxide was coated with iron hydroxide.

After stirring for 1 hour, the mixture was filtered and washed, and dried at 110 ° C. The dried product was placed in a magnetic crucible and baked at 900 ° C. for 1 hour in an electric furnace to synthesize titanium oxide having an Fe ₂ TiO ₅ phase. After cooling, the obtained titanium oxide having the Fe ₂ TiO ₅ phase was reduced with a mixed gas of hydrogen gas and carbon dioxide gas at 500 ° C. for 5 hours to obtain a black powder.

[Image forming functional layer coating solution]
Table 3 shows details of the material of the image forming functional layer coating solution.

(Application of lower and upper hydrophilic layers)
The lower hydrophilic layer coating solution was applied on the undercoating surface A of the substrate 1 using a wire bar so that the dry mass was 2.8 g / m ² , and the drying was set to 100 ° C. with a length of 15 m. The zone was passed at a conveying speed of 15 m / min.

Subsequently, the upper hydrophilic layer coating solution was applied using a wire bar to a dry mass of 1.80 g / m ² , and the drying zone set at 100 ° C. with a length of 30 m was transported at a conveyance speed of 15 m / min. Passed at speed.

On the other hand, the base material 2 (aluminum base material) is applied to the upper hydrophilic layer only using a wire bar so that the dry mass becomes 1.80 g / m ² , and is set to 100 ° C. with a length of 30 m. The dried zone was passed at a conveying speed of 15 m / min. The sample after application was aged at 60 ° C. for 2 days.

(Application of image forming functional layer coating solution)
The image forming functional layer coating solution having the composition shown in Table 3 below was applied on the upper hydrophilic layer prepared above using a wire bar so that the dry mass was 0.55 g / m ^2, and the length was 30 m. The image forming functional layer was formed by passing through a drying zone set at 70 ° C. at a conveyance speed of 15 m / min. The coated sample was aged at 50 ° C. for 2 days to obtain a lithographic printing plate material.

  The lithographic printing plate material was cut to a width of 660 mm, and the one using the substrate 1 (PET substrate) was wound 30 m on a paper core having an outer diameter of 76 mm to obtain a rolled lithographic printing plate material. On the other hand, what used the base material 2 (aluminum base material) was also cut to 660 mm width, and the sheet-like planographic printing plate material was obtained.

  The material of the upper hydrophilic layer or the image forming functional layer (infrared dye) was changed as shown in Table 4.

[Evaluation]
Exposure Method The printing plate sample was cut to fit the exposure size, and then wound around the exposure drum and fixed. A laser beam having a wavelength of 830 nm and a spot diameter of about 18 μm is used for exposure, and the exposure energy is 240 mJ / cm ² , and 2,400 dpi (dpi represents the number of dots per 2.54 cm), and an image with 175 lines. A formed lithographic printing plate sample was formed. The lithographic printing plate on which the image was formed was immediately mounted on the following printing apparatus and printed.

Printing method Printing device: DAIYA1-F manufactured by Mitsubishi Heavy Industries, Ltd., dampening solution is ASTROMARK 3 (manufactured by Nikken Chemical Research Co., Ltd.), 2% by weight aqueous solution, ink is space color fusion G ST red N ( Printing evaluation was performed using Dainippon Ink & Chemicals, Inc. Printing was performed using coated paper except for evaluation of printing durability. At the time of front printing, powder (trade name: Nikka Rico M (manufactured by Nikka Corporation)) was used and sprayed on the powder scale 10 of the printing apparatus.

<< Sensitivity evaluation >>
Samples for which the exposure visibility was obtained were evaluated with a loupe, and the appropriate exposure energy was evaluated. The appropriate exposure energy is the exposure energy at which a 50% halftone dot has a halftone dot area of 50%, and the results are shown in Table 4. The smaller the value, the higher the sensitivity.

《Evaluation of initial ink fillability》
The printing start sequence was the PS printing sequence. When the plate surface was observed after printing, the non-image area was removed from the planographic printing plate sample according to the present invention.

  The printing start sequence was carried out using the PS printing sequence, and it was evaluated at what number the ink smears in the non-image area disappeared. The smaller the number of sheets, the better the ink fillability. The results are shown in Table 4.

<Evaluation of printing durability>
Similarly, the exposed lithographic printing plate sample was put on the printing machine and 50,000 sheets were printed on the surface side under the above conditions. After the ink was dried, it was reversed and the back side was printed up to 50,000 sheets under the above conditions. The number of printed sheets in which more than half of the dots in the 3% halftone dot image on the back side were missing was determined as the number of printed sheets. The higher the number of prints, the better.

<Evaluation of stain recovery properties>
1000 exposed lithographic printing plate samples were printed on coated paper. Thereafter, normal printing (nip of both the ink roller and the water roller) was performed in a state where only the ink roller was nipped and ink was adhered to the entire surface. At that time, the number of non-imaged areas in the printed material that was not stained was measured and used as an index for the stain recovery. A smaller number is better.

  Table 4 shows the results obtained as described above.

  From Table 4, it can be seen that the planographic printing plate material of the present invention has high sensitivity and is excellent in initial ink setting, printing durability, and stain recovery.

Claims (3)

In a lithographic printing plate material having a hydrophilic layer on a substrate and an image forming functional layer developable on a printing press, at least one layer on the image forming functional layer side has the following general formulas (1), (2), (3) And a lithographic printing plate material comprising at least one compound selected from (4).

(In the formula, A ₁ and B ₁ represent substituents.)

(In the formula, A ₂ and B ₂ represent substituents.)

(In the formula, R ₁ and R ₂ represent a hydrogen atom or an alkyl group. A ₃ and B ₃ represent the axis of the axis connecting a bond point between the carbon atom shown by C in the general formula and the carbon atom. This represents a group that can completely overlap with the original group when rotated 180 ° around (however, the sum of the hydroxyl groups of A ₃ and B ₃ is 0 or more and 1 or less.)

(In the formula, R ₃ and R ₄ represent a hydrogen atom or an alkyl group. A ₄ and B ₄ represent the axis of the line connecting the carbon atom and the bond point indicated by C in the general formula. Represents a group that can completely overlap with the original group when rotated 180 ° around (provided that the total of hydroxyl groups of A ₄ and B ₄ is from 0 to 1). The lithographic printing plate material according to claim 1, wherein the image-forming functional layer contains heat-fusible particles or heat-fusible particles. The lithographic printing plate material according to claim 1 or 2 is image-exposed and then mounted on a printing machine, and dampening water and ink are supplied to the surface of the lithographic printing plate material to remove non-image parts and printing. A lithographic printing method.