JP2002079772A - Original film for lithographic printing plate, method of making lithographic printing plate using the same and method of printing - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an original film for a lithographic printing plate having excellent on-press developability and high sensitivity, showing high plate wear and being excellent in scumming properties (ink clearing properties) in printing, a method of making the lithographic printing plate using the same and a method of printing. SOLUTION: The original film has a hydrophilic layer and a heat-sensitive layer containing microcapsules each containing a compound having a thermally reactive functional group, in this sequence, on a plastic film substrate. The film is subjected to image exposure by laser light and mounted, as it is, on a press to be subjected to printing. In another way, the film is subjected to the image exposure on the press by the laser light after it is mounted thereon, and subjected to printing as it is.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lithographic printing plate precursor for a computer-to-plate system which does not require development, and a lithographic printing plate making and printing method using the same. More specifically, it is possible to record an image by infrared scanning exposure based on a digital signal, and the recorded image can be directly attached to a printing machine and printed without going through a conventional liquid developing process. The present invention relates to a possible lithographic printing plate precursor and a method of making and printing a lithographic printing plate using the same.

[0002]

2. Description of the Related Art With regard to lithographic printing plates for computer-to-plate systems, which have been remarkably progressing in recent years,
Numerous studies have been done. Among them, with the aim of further streamlining the process and solving the problem of waste liquid treatment, a planographic printing plate precursor that can be directly mounted on a printing machine and printed after exposure has been studied, and various methods have been proposed. One promising method is a lithographic printing plate precursor in which a hydrophilic layer in which hydrophobic thermoplastic polymer particles are dispersed in a hydrophilic binder polymer is used as an image forming layer (thermosensitive layer). This method utilizes the fact that when heat is applied to the heat-sensitive layer, the hydrophobic thermoplastic polymer particles are fused and the surface of the hydrophilic heat-sensitive layer is converted into an oleophilic image area.

One of the methods utilizing the thermal fusion of the hydrophobic thermoplastic polymer particles to eliminate the processing step is to mount an exposed lithographic printing plate precursor on a cylinder of a printing machine, There is a method called on-press development in which a non-image portion of a lithographic printing plate precursor is removed by supplying a dampening solution and ink while rotating the plate. That is, the lithographic printing plate precursor is mounted on a printing machine as it is after exposure, and the processing is completed in a normal printing process. A lithographic printing plate precursor suitable for such on-press development has a photosensitive layer that is soluble in fountain solution and ink solvent, and is suitable for development on a printing machine placed in a bright room. It is necessary to have a light room handling property.

For example, Japanese Patent No. 2938397 discloses a lithographic printing plate precursor in which a photosensitive layer in which fine particles of a thermoplastic hydrophobic polymer are dispersed in a hydrophilic binder polymer is provided on a hydrophilic support. ing. In this publication,
In the lithographic printing plate precursor, an image is formed by exposing the thermoplastic hydrophobic polymer particles by heat by exposing the plate to infrared rays, and then mounting the plate on a cylinder of a printing press and supplying fountain solution and / or ink. It is described that on-press development can be performed by carrying out.

Further, Japanese Patent Application Laid-Open Nos. 9-127683 and WO99-10186 also disclose that a printing plate is prepared by on-press development after combining thermoplastic fine particles by heat. However, such a method of forming an image by coalescence of fine particles by heat shows good on-press developability, but the adhesion between the aluminum support and the image is weak, and the image strength is also low, so that the printing durability is poor. Was insufficient. As a countermeasure against this, it is known to use a phosphoric acid bath anodic oxide film having a strong adhesive force, but this method has a drawback in that the stain property (ink removal property) in printing deteriorates.

Further, Japanese Patent Application Laid-Open No. 8-48020 discloses that
A method is described in which a lipophilic thermosensitive layer is provided on a porous hydrophilic support, exposed to infrared laser, and the lipophilic thermosensitive layer is fixed to a substrate by heat. However, a lipophilic film has poor on-press developability, and there is a problem that scum of the lipophilic thermosensitive layer adheres to an ink roller or printed matter.

[0007]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a lithographic printing plate precursor which overcomes the above-mentioned drawbacks of the prior art, and a lithographic printing plate making and printing method using the same. That is, having good on-press developability,
It is an object of the present invention to provide a lithographic printing plate precursor having high sensitivity, high printing durability, and good stainability (ink removal property) in printing, and a lithographic printing plate making and printing method using the same. .

[0008]

Means for Solving the Problems As a result of diligent studies, the present inventor has ensured printing durability by improving the image strength with a heat-reactive compound and improving the thermal reactivity with a heat-insulating plastic support, Further, it has been found that the above-mentioned object can be achieved by improving the printing stain by a specific hydrophilic layer,
The present invention has been reached. That is, the present invention is as follows. (1) a hydrophilic layer on a plastic film support,
A lithographic printing plate precursor comprising, in this order, a heat-sensitive layer containing microcapsules containing a compound having a heat-reactive functional group.

(2) The lithographic printing plate precursor as described in (1) above, wherein the hydrophilic layer contains an inorganic matrix formed by sol-gel conversion. (3) The lithographic printing plate precursor as described in (1) above, wherein the hydrophilic layer is an inorganic thin film having a surface containing a metal oxide. (4) The lithographic printing plate precursor as described in any of (1) to (3) above, further including a water-soluble overcoat layer on the heat-sensitive layer.

(5) On a plastic film support,
A lithographic printing plate precursor having, in this order, a hydrophilic layer and a heat-sensitive layer containing microcapsules containing a compound having a heat-reactive functional group, is image-exposed by laser light,
A plate making and printing method for a lithographic printing plate, wherein the lithographic printing plate is mounted on a printing machine as it is for printing, or after being mounted on the printing machine, image-exposed with a laser beam on the printing machine and printed.

According to the present invention, there is provided an on-press development type lithographic printing plate precursor that can be directly mounted on a printing press and printed as it is after image exposure with a laser beam, and has excellent on-press developability. Having high sensitivity and high printing durability,
Moreover, it is possible to obtain a lithographic printing plate precursor free of stains in printing.

[0012]

Embodiments of the present invention will be described below in detail. The lithographic printing plate precursor according to the invention has a hydrophilic layer and a heat-sensitive layer containing microcapsules containing a compound having a thermoreactive functional group on a plastic film support in this order.

[Plastic Support] It is important that the support used in the present invention is heat-insulating in order to promote the thermal reaction of the heat-sensitive layer, and has a thermal conductivity of 0.03 ca.
1 / cm · sec · ° C. or less.
It is more preferable that the temperature is not more than 01 cal / cm · sec · ° C. For this reason, a plastic support is used in the present invention. As the plastic support used in the present invention, a dimensionally stable plate which has flexibility enough to be set in an ordinary printing press and at the same time withstands a load applied during printing is used. For example, paper laminated with plastic (eg, polyethylene, polypropylene, polystyrene, etc.), paper coated with an organic polymer resin, plastic film (eg, cellulose diacetate, cellulose triacetate, cellulose propionate, cellulose butyrate, Cellulose acetate butyrate, cellulose nitrate, polyethylene terephthalate, polyethylene naphthalate, polyethylene, polystyrene, polypropylene, polycarbonate, polyvinyl acetal, etc.), the plastic film coated with an organic polymer resin, the plastic film in which pigments are dispersed,
The above-mentioned plastic film containing a cavity is included.

The support of the present invention is preferably provided with an antistatic layer on the hydrophilic layer side, on the opposite side, or on both sides of the support as long as the heat insulating property of the support is not impaired. When the antistatic layer is provided between the support and the hydrophilic layer, it also contributes to improving the adhesion to the hydrophilic layer. As the antistatic layer, a polymer layer in which metal oxide fine particles and a matting agent are dispersed can be used.

The metal oxide particles used in the antistatic layer
The material is SiO_Two, ZnO, TiO_Two, SnO_Two,
Al_TwoO_Three, In_TwoO_Three, MgO, BaO, MoO_Three, V_TwoO
_FiveAnd their composite oxides and / or their metal acids
Can further include metal oxides containing heteroatoms.
Wear. These may be used alone or in combination.
Good. Preferred metal oxides include SiO 2_Two, Zn
O, SnO_Two, Al_TwoO_Three, TiO _Two, In_TwoO_ThreeWith MgO
is there. As an example containing a small amount of a heteroatom, ZnO
Al or In, SnO_TwoSb, Nb or
Is a halogen element, In_TwoO_ThreeHeterogeneous atoms such as Sn
In an amount of 30 mol% or less, preferably 10 mol% or less.
Can be mentioned. Metal oxide particles
Is contained in the antistatic layer in the range of 10 to 90% by weight.
Is preferred. The average particle size of the metal oxide particles is
The particle diameter is preferably in the range of 0.001 to 0.5 μm. This
The average particle size here is the primary particle size of the metal oxide particles.
The value includes not only the particle size of the higher-order structure but also the particle size of the higher-order structure.

The matting agent that can be used in the antistatic layer is preferably an inorganic or organic particle having an average particle diameter of 0.5 to 20 μm, more preferably an average particle diameter of 1.0 to 15 μm. Is mentioned. As inorganic particles,
Examples thereof include metal oxides such as silicon oxide, aluminum oxide, titanium oxide, and zinc oxide, and metal salts such as calcium carbonate, barium sulfate, barium titanate, and strontium titanate. Examples of the organic particles include cross-linked particles of polymethyl methacrylate, polystyrene, polyolefin, and a copolymer thereof. The matting agent is preferably contained in the antistatic layer in a range of 1 to 30% by weight.

Examples of the polymer which can be used in the antistatic layer include proteins such as gelatin and casein; cellulose compounds such as carboxymethylcellulose, hydroxyethylcellulose, acetylcellulose, diacetylcellulose and triacetylcellulose; dextran, agar and sodium alginate. , Sugars such as starch derivatives, polyvinyl alcohol, polyvinyl acetate, polyacrylate, polymethacrylate, polystyrene, polyacrylamide, polyvinylpyrrolidone,
Examples include synthetic polymers such as polyester, polyvinyl chloride, polyacrylic acid, and polymethacrylic acid. The polymer is preferably contained in the antistatic layer in the range of 10 to 90% by weight.

The thickness of the antistatic layer is preferably from 0.01 to 1 μm. In addition, the surface of the support used in the present invention on the hydrophilic layer side is roughened by sandblasting or surface modified by corona treatment from the viewpoint of improving the surface area of the hydrophilic layer and improving the adhesion to the upper layer. Can be applied.

The support used in the present invention has a maximum roughness depth (R) on the back surface of the support from the viewpoint of preventing blocking.
t) is preferably at least 1.2 μm or more, and when the back surface of the support (that is, the back surface of the lithographic printing plate precursor of the present invention) slides on the surface of the lithographic printing plate precursor of the present invention. Has a dynamic friction coefficient (μk) of 2.6 or less. For this reason, it is preferable that the back surface of the support is roughened by providing an antistatic layer containing the above-mentioned matting agent, or by performing sandblasting. The thickness of the support used in the present invention is about 0.05.
It is about 0.6 mm, preferably about 0.1 to 0.4 mm, particularly preferably 0.15 to 0.3 mm.

[Hydrophilic layer] Next, the hydrophilic layer provided on the support in the lithographic printing plate precursor according to the invention will be described. As the hydrophilic layer used in the present invention, for example, an organic hydrophilic matrix obtained by crosslinking or pseudo-crosslinking an organic hydrophilic polymer, polyalkoxysilane, titanate, zirconate or aluminate hydrolysis, condensation reaction A layer having an inorganic hydrophilic matrix obtained by sol-gel conversion, or an inorganic thin film having a surface containing a metal oxide. An inorganic thin film having a containing surface is preferred.

As the crosslinking reaction used for forming the organic hydrophilic matrix of the hydrophilic layer of the present invention, a covalent bond can be formed by heat or light, or an ionic bond can be formed by a polyvalent metal salt. As the organic hydrophilic polymer used in the present invention, a polymer having a functional group that can be used for a crosslinking reaction is preferable. Preferred functional groups include, for example,
_{-OH, -SH, -NH 2, -NH} -, - CO-NH
₂ , -CO-NH-, -O-CO-NH-, -NH-C
O-NH-, -CO-OH, -CO-O-, -CO-O
^- , -CS-OH, -CO-SH, -CS-SH, -S
O ₃ H, —SO ₂ (O ⁻ ), —PO ₃ H ₂ , —PO (O
^{_{-) 2, -SO 2 -NH 2}} , -SO 2 -NH -, - CH =
_{CH 2, -CH = CH -,} - CO-C (CH 3) = C
_{H 2, -CO-CH = CH} 2, -CO-CH 2 -CO-,
—CO—O—CO— and the following functional groups.

[0022]

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Particularly, a hydroxyl group, an amino group, a carboxyl group and an epoxy group are preferred.

As such an organic hydrophilic polymer of the present invention, a known water-soluble binder can be used. For example, polyvinyl alcohol (a saponification degree of 60%
Polyvinyl acetate), modified polyvinyl alcohol such as carboxy-modified polyvinyl alcohol, starch and derivatives thereof, carboxymethyl cellulose and salts thereof, cellulose derivatives such as hydroxyethyl cellulose, casein, gelatin, gum arabic, polyvinyl pyrrolidone, vinyl acetate-crotonic acid Copolymer and its salt, styrene-maleic acid copolymer and its salt, polyacrylic acid and its salt, polymethacrylic acid and its salt,
Polyethylene glycol, polyethyleneimine, polyvinylphosphonic acid and its salt, polystyrenesulfonic acid and its salt, poly (methacryloyloxypropanesulfonic acid) and its salt, polyvinylsulfonic acid and its salt, poly (methacryloyloxyethyltrimethylammonium chloride) , Polyhydroxyethyl methacrylate,
Polyhydroxyethyl acrylate, polyacrylamide and the like can be mentioned. These polymers may be copolymers as long as hydrophilicity is not impaired, and may be used alone or in combination of two or more. The amount used is from 20% by weight to 99% by weight, preferably from 25% by weight to 95% by weight, based on the total solid weight of the hydrophilic layer,
More preferably, it is 30% by weight to 90% by weight.

In the present invention, the organic hydrophilic polymer can be crosslinked with a known crosslinking agent. Known crosslinking agents include polyfunctional isocyanate compounds, polyfunctional epoxy compounds, polyfunctional amine compounds, polyol compounds, polyfunctional carboxyl compounds, aldehyde compounds,
Polyfunctional (meth) acrylic compound, polyfunctional vinyl compound,
Polyfunctional mercapto compounds, polyvalent metal salt compounds, polyalkoxysilane compounds and their hydrolysates, polyalkoxytitanium compounds and their hydrolysates, polyalkoxyaluminum compounds and their hydrolysates, polymethylol compounds, polyalkoxymethyl compounds, etc. It is also possible to add a known reaction catalyst to accelerate the reaction. The use amount thereof is 1% by weight to 50% by weight, preferably 3% by weight to 40% by weight, more preferably 5% by weight to 35% by weight based on the total solid content in the coating solution of the hydrophilic layer. .

The system capable of sol-gel conversion which can be used for forming the inorganic hydrophilic matrix of the hydrophilic layer of the present invention has a network structure in which a bonding group derived from a polyvalent element has a network structure via an oxygen atom. At the same time, the polyvalent metal also has an unbonded hydroxyl group or alkoxy group, and is a polymer having a resin-like structure in which these are mixed. Yes, the network-like resin structure becomes stronger as the ether bond progresses. In addition, it also has a function of modifying the surface of the solid fine particles by binding a part of the hydroxyl group to the solid fine particles and changing the degree of hydrophilicity. The polyvalent bonding element of the compound having a hydroxyl group or an alkoxy group that undergoes sol-gel conversion is aluminum, silicon, titanium, zirconium, or the like, and any of these can be used in the present invention. A sol-gel conversion system based on a siloxane bond will be described. aluminum,
The sol-gel conversion using titanium and zirconium can be carried out by substituting silicon for each element described below.

That is, particularly preferably used are:
This is a system containing a silane compound having at least one silanol group and capable of sol-gel conversion. Hereinafter, a system utilizing the sol-gel conversion will be further described. The inorganic hydrophilic matrix formed by the sol-gel conversion is preferably a resin having a siloxane bond and a silanol group. During the drying and aging, the hydrolytic condensation of the silanol groups proceeds to form the structure of the siloxane skeleton, which is formed by the progress of gelation.

In the matrix having the gel structure, the organic hydrophilic polymer and the crosslinking agent described above are used for the purpose of improving physical properties such as film strength and flexibility, improving coating properties and adjusting hydrophilicity. Can also be added. The siloxane resin forming a gel structure is represented by the following general formula (I)
And a silane compound having at least one silanol group is obtained by hydrolysis of a silane compound represented by the following general formula (II), and is not necessarily a partial hydrolyzate of the silane compound represented by the general formula (II) alone. Need not be
In general, the silane compound may be composed of a partially hydrolyzed oligomer, or may be a mixed composition of the silane compound and its oligomer.

[0029]

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The siloxane resin represented by the general formula (I) is
It is formed by sol-gel conversion of at least one compound of the silane compounds represented by the following general formula (II), wherein at least one of R ^{01 to} R ^{03 in} the general formula (I) represents a hydroxyl group, and Represents an organic residue selected from the symbols R ⁰ and Y in the general formula (II).

Formula (II) (R ⁰ ) _n Si (Y) _4-n

In the general formula (II), R ⁰ represents a hydroxyl group, a hydrocarbon group or a heterocyclic group. Y represents a hydrogen atom, a halogen atom (representing a fluorine atom, a chlorine atom, a bromine atom or an iodine atom), —OR ¹ , —OCOR ^2, or —N (R
³ ) represents (R ⁴ ) (R ¹ and R ² each represent a hydrocarbon group, and R ³ and R ⁴ may be the same or different and represent a hydrogen atom or a hydrocarbon group), and n is 0, Represents 1, 2, or 3.

The hydrocarbon group or heterocyclic group represented by R ^{0 in} the general formula (II) is, for example, a linear or branched alkyl group having 1 to 12 carbon atoms which may be substituted (for example, methyl group , Ethyl group, propyl group, butyl group, pentyl group,
A hexyl group, a heptyl group, an octyl group, a nonyl group, a decyl group, a dodecyl group, etc .; Group, sulfo group, cyano group, epoxy group, -OR 'group (R' is a methyl group, an ethyl group, a propyl group, a butyl group, a heptyl group, a hexyl group, an octyl group, a decyl group, a propenyl group, a butenyl group, Hexenyl group, octenyl group, 2-hydroxyethyl group, 3-chloropropyl group, 2-cyanoethyl group, N, N-dimethylaminoethyl group, 1-bromoethyl group, 2- (2-methoxyethyl) oxyethyl group, 2- A methoxycarbonylethyl group, a 3-carboxypropyl group, a benzyl group, etc.), an -OCOR "group (R" is the same as the above R ') ), -COO
R ″ group, —COR ″ group, —N (R ′ ″) (R ′ ″) group (R ′ ″ represents a hydrogen atom or the same content as R ′, and is the same or different. ), -NHCONH
R "group, -NHCOOR" group, -Si (R ") ₃ group,-
CONHR ′ ″ group, —NHCOR ″ group and the like.
These substituents may be substituted plurally in the alkyl group),

A linear or branched alkenyl group having 2 to 12 carbon atoms which may be substituted (for example, vinyl, propenyl, butenyl, pentenyl, hexenyl, octenyl, decenyl, dodecenyl and the like) And the groups substituted with these groups include those having the same contents as the groups substituted with the above-mentioned alkyl groups), having 7-14 carbon atoms.
Optionally substituted aralkyl groups (for example, benzyl group, phenethyl group, 3-phenylpropyl group, naphthylmethyl group, 2-naphthylethyl group, etc .; Groups having the same content as the group to be mentioned, or may be substituted plurally),

An optionally substituted alicyclic group having 5 to 10 carbon atoms (for example, cyclopentyl, cyclohexyl, 2
-Cyclohexylethyl group, 2-cyclopentylethyl group, norbornyl group, adamantyl group and the like, the group substituted with these groups include those having the same contents as the substituents of the alkyl group, and those substituted with a plurality of May be substituted), an aryl group having 6 to 12 carbon atoms which may be substituted (for example,
A phenyl group or a naphthyl group, wherein the substituent has the same content as the group substituted with the alkyl group, and may be substituted plurally), or a nitrogen atom, an oxygen atom,
A condensable heterocyclic group containing at least one atom selected from sulfur atoms (for example, the heterocyclic ring includes a pyran ring, a furan ring, a thiophene ring, a morpholine ring, a pyrrole ring, a thiazole ring, and an oxazole A ring, a pyridine ring, a piperidine ring, a pyrrolidone ring, a benzothiazole ring, a benzoxazole ring, a quinoline ring, a tetrahydrofuran ring, etc., which may contain a substituent. The same content may be mentioned, or a plurality of the same may be substituted).

In the general formula (II), -OR ¹ group of Y, -OC
As a substituent of the OR ² group or the —N (R ³ ) (R ⁴ ) group,
For example, it represents the following substituents. -OR In ^one group, R
¹ is an aliphatic group having 1 to 10 carbon atoms which may be substituted (for example, methyl group, ethyl group, propyl group, butyl group, heptyl group, hexyl group, pentyl group, octyl group, nonyl group, decyl group, propenyl group) Group, butenyl group, heptenyl group, hexenyl group, octenyl group, decenyl group, 2-hydroxyethyl group, 2-hydroxypropyl group, 2-methoxyethyl group, 2- (methoxyethyloxo) ethyl group, 1- (N, N-diethylamino) ethyl group, 2-methoxypropyl group, 2-cyanoethyl group, 3-methyloxapropyl group, 2-chloroethyl group, cyclohexyl group, cyclopentyl group, cyclooctyl group, chlorocyclohexyl group, methoxycyclohexyl group, benzyl group , Phenethyl group, dimethoxybenzyl group, methylbenzyl group, bromobenzyl And the like).

In the —OCOR ² group, R ² is an aliphatic group having the same content as R ¹ or an aromatic group having 6 to 12 carbon atoms which may be substituted (the aromatic group is an aryl group in the aforementioned R). And the same as those exemplified for the group). In the —N (R ³ ) (R ⁴ ) group, R ³ , R ⁴
May be the same as or different from each other, and each may be a hydrogen atom or an aliphatic group having 1 to 10 carbon atoms which may be substituted (for example, those having the same contents as R ^{1 of the} above-mentioned OR ¹ group) ). More preferably, the total number of carbon atoms of R ³ and R ⁴ is 16 or less. Specific examples of the silane compound represented by the general formula (II) include the following, but are not limited thereto.

Tetrachlorosilane, tetrabromosilane, tetramethoxysilane, tetraethoxysilane, tetraisopropoxysilane, tetra-n-propylsilane, tetra-t-butoxysilane, tetra-n-butoxysilane, dimethoxydiethoxysilane, methyltrichlorosilane , Methyltribromosilane, methyltrimethoxysilane, methyltriethoxysilane, methyltriisopropoxysilane, methyltri-t-butoxysilane, ethyltrichlorosilane, ethyltribromosilane, ethyltrimethoxysilane, ethyltriethoxysilane, ethyltriiso Propoxysilane, ethyltri-t-butoxysilane, n-propyltrichlorosilane, n-propyltribromosilane, n-propyltrimethoxysilane,
n-propyltriethoxysilane, n-propyltriisopropoxysilane, n-propyltri-t-butoxysilane, n-hexyltrichlorosilane, n-hexyltribromosilane, n-hexyltrimethoxysilane, n
-Hexyltriethoxysilane, n-hexyltriisopropoxysilane, n-hexyltri-t-butoxysilane, n-decyltrichlorosilane, n-decyltribromosilane, n-decyltrimethoxysilane, n-decyltriethoxysilane, n -Decyltriisopropoxysilane, n-decyltri-t-butoxysilane, n-octadecyltrichlorosilane, n-octadecyltribromosilane, n-octadecyltrimethoxysilane, n-octadecyltriethoxysilane, n-octadecyltriisopropoxysilane, n-octadecyltri-t-butoxysilane, phenyltrichlorosilane, phenyltribromosilane, phenyltrimethoxysilane, phenyltriethoxysilane, phenyltriisopropoxysilane, phenyltrisilane -Butoxysilane, dimethyldichlorosilane, dimethyldibromosilane, dimethyldimethoxysilane, dimethyldiethoxysilane, diphenyldichlorosilane, diphenyldibromosilane, diphenyldimethoxysilane, diphenyldiethoxysilane, phenylmethyldichlorosilane, phenylmethyl Dibromosilane, phenylmethyldimethoxysilane, phenylmethyldiethoxysilane,

Triethoxyhydrosilane, tribromohydrosilane, trimethoxyhydrosilane, isopropoxyhydrosilane, tri-tert-butoxyhydrosilane, vinyltrichlorosilane, vinyltribromosilane, vinyltrimethoxysilane, vinyltriethoxysilane, vinyltriisopropoxysilane, Vinyl tri-t-butoxysilane, trifluoropropyltrichlorosilane, trifluoropropyltribromosilane, trifluoropropyltrimethoxysilane, trifluoropropyltriethoxysilane, trifluoropropyltriisopropoxysilane, trifluoropropyltri-t-butoxysilane, γ-glycidoxypropylmethyldimethoxysilane, γ-glycidoxypropylmethyldiethoxysilane, γ-glycidoxip Pills trimethoxysilane, gamma
-Glycidoxypropyltriethoxysilane, γ-glycidoxypropyltriisopropoxysilane, γ-glycidoxypropyltri-t-butoxysilane, γ-methacryloxypropylmethyldimethoxysilane, γ-methacryloxypropylmethyldiethoxysilane Γ-methacryloxypropyltrimethoxysilane, γ-methacryloxypropyltriisopropoxysilane, γ-methacryloxypropyltri-t-butoxysilane, γ-aminopropylmethyldimethoxysilane, γ-aminopropylmethyldiethoxysilane, γ- Aminopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, γ
-Aminopropyltriisopropoxysilane, γ-aminopropyltri-t-butoxysilane, γ-mercaptopropylmethyldimethoxysilane, γ-mercaptopropylmethyldiethoxysilane, γ-mercaptopropyltrimethoxysilane, γ-mercaptopropyltriethoxysilane , Γ-mercaptopropyltriisopropoxysilane, γ-mercaptopropyltri-t-butoxysilane, β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, β- (3,4-epoxycyclohexyl) ethyltriethoxysilane, etc. Is mentioned.

Along with the silane compound represented by the general formula (II) used for forming the inorganic hydrophilic matrix of the hydrophilic layer of the present invention, the silane compound binds to the resin during the sol-gel conversion of Ti, Zn, Sn, Zr, Al and the like. And a metal compound capable of forming a film. Examples of the metal compound used include Ti (OR ⁵ ) ₄ R ^{5, which} is a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, etc.), TiC
l ₄ , Ti (CH ₃ COCHCOCH ₃ ) ₂ (OR ⁵ ) ₂ , Z
n (OR ⁵ ) ₂ , Zn (CH ₃ COCHCOCH ₃ ) ₂ , S
n (OR ⁵ ) ₄ , Sn (CH ₃ COCHCOCH ₃ ) ₄ , S
n (OCOR ⁵ ) ₄ , SnCl ₄ , Zr (OR ⁵ ) ₄ , Zr
(CH ₃ COCHCOCH ₃ ) ₄ , Al (OR ⁵ ) ₃ , Al
(CH ₃ COCHCOCH ₃ ) _{3 and the} like.

Further, in order to promote the hydrolysis and polycondensation reaction of the silane compound represented by the general formula (II), and the metal compound used in combination, it is preferable to use an acidic catalyst or a basic catalyst in combination. As the catalyst, an acid or basic compound used as it is or in a state of being dissolved in a solvent such as water or alcohol (hereinafter referred to as an acidic catalyst or a basic catalyst, respectively) is used. The concentration at that time is not particularly limited, but when the concentration is high, hydrolysis /
The rate of polycondensation tends to increase. However, when a basic catalyst having a high concentration is used, a precipitate may be formed in the sol solution. Therefore, the degree of the basic catalyst is preferably 1 N (concentration conversion in an aqueous solution) or less.

The type of the acidic catalyst or the basic catalyst is not particularly limited, and specific examples of the acidic catalyst include hydrogen halides such as hydrochloric acid, nitric acid, sulfuric acid, sulfurous acid, hydrogen sulfide, perchloric acid, and hydrogen peroxide. Examples of basic catalysts include ammonia, such as carboxylic acids such as carbonic acid, formic acid and acetic acid, substituted carboxylic acids in which R of the structural formula represented by RCOOH is substituted with another element or a substituent, and sulfonic acids such as benzenesulfonic acid. Examples include ammoniacal bases such as water and amines such as ethylamine and aniline.

For further details of the above sol-gel method, refer to Saio Sakuhana, “Sol-gel Method Science”, Agne Shofusha Co., Ltd.
(1988), Takashi Hirashima, "Functional thin film production technology by latest sol-gel method", General Technology Center (published) (1992)
It is described in detail in written documents such as year.

In the hydrophilic layer of the organic or inorganic hydrophilic matrix of the present invention, in addition to the above, the degree of hydrophilicity is controlled, the physical strength of the hydrophilic layer is improved, and the composition constituting the layer is different. Various compounds can be added to improve the dispersibility, coatability, printability, and the like. For example, plasticizers, pigments, dyes, surfactants, hydrophilic particles and the like can be mentioned.

The hydrophilic particles are not particularly limited, but preferably include silica, alumina, titanium oxide, magnesium oxide, magnesium carbonate, calcium alginate and the like. These can be used for promoting hydrophilicity, strengthening a film, and the like. More preferably, it is silica, alumina, titanium oxide or a mixture thereof. In a preferred embodiment, the hydrophilic layer of the organic or inorganic hydrophilic matrix of the present invention particularly contains metal oxide particles such as silica, alumina, and titanium oxide.

Silica has many hydroxyl groups on the surface, and the inside constitutes a siloxane bond (—Si—O—Si—). In the present invention, silica that can be preferably used is ultrafine silica particles having a particle diameter of 1 to 100 nm, also referred to as colloidal silica, dispersed in water or a polar solvent. Specifically, it is described in “Applied Technology of High-Purity Silica”, edited by Yoshitoshi Kaga and Akira Hayashi, Vol. 3, CMC Corporation (1991).

Alumina which can be preferably used is an alumina hydrate (boehmite) having a colloidal size of 5 to 200 nm, and an anion (for example, a halogen atom ion such as a fluorine ion or a chlorine ion) in water. , A carboxylate anion such as an acetate ion) as a stabilizer. The titanium oxide that can be preferably used has an average primary particle size of 50 to 500.
nm anatase or rutile titanium oxide,
If necessary, it is dispersed in water or a polar solvent using a dispersant.

In the present invention, the average primary particle diameter of the hydrophilic particles that can be preferably used is 1 to 5000 nm.
And more preferably 10 to 1000 nm.
In the hydrophilic layer of the present invention, these hydrophilic particles may be used alone or in combination of two or more. The amount used is based on the total solid weight of the hydrophilic layer.
It is 5% to 90% by weight, preferably 10% to 70% by weight, more preferably 20% to 60% by weight.

The hydrophilic layer of the organic or inorganic hydrophilic matrix used in the present invention may be dissolved or dispersed in a suitable solvent such as water or a polar solvent such as methanol or ethanol alone or in a mixed solvent thereof. Is applied, dried and cured on the light-to-heat conversion layer. Its coating weight in weight after drying is suitably from 0.1-5 g / m ^2, preferably from 0.3 to 3 g / m ^2, more preferably 0.5 to 2 g /
m ² . The coating weight of the hydrophilic layer after drying is 0.1 g.
When / m ² than too low, dampening decrease in retention of water, giving undesirable results such as reduced film strength and as high as higher than 5 g / m ^2, the film becomes brittle, reduction in printing durability Gives undesired results.

The inorganic thin film having a surface containing a metal oxide used for the hydrophilic layer of the present invention is not particularly limited as long as the surface of the thin film is composed of a hydrophilic metal oxide. Includes thin films of metals or metal compounds having objects on the surface. Examples of the metal or metal compound that can be used in the hydrophilic layer of the present invention include d-block (transition) metal, f-block (lanthanoid) metal, aluminum, indium, lead, tin, silicon, and alloys and respective metals. Metal oxides, metal carbides, metal nitrides, metal borides, metal sulfides, and metal halides, which are mixed (including uniform mixed films, non-uniform mixed films and laminated films). It can also be used.

Among them, a metal oxide thin film itself is particularly preferable. Examples of the metal oxide thin film include thin films of indium oxide, tin oxide, tungsten oxide, manganese oxide, silicon oxide, titanium oxide, aluminum oxide, zirconium oxide, and the like. The mixed thin film can be suitably used as the hydrophilic layer of the present invention. The surface of the thin film of the metal and the metal compound is substantially in a highly oxidized state in the air, and the surface is composed of a metal oxide and can be used in the present invention. In order to ensure the hydrophilicity of the hydrophilic layer, it is essential that the surface of the inorganic thin film that is the hydrophilic layer is composed of a metal oxide. For this reason, after forming the thin film, a treatment such as a heat treatment, a humidification treatment, or a glow discharge treatment may be performed to promote oxidation of the surface. Further, a metal oxide may be stacked on the surface of the thin film.

For forming a thin film of a metal or a metal compound used in the hydrophilic layer of the present invention, a PVD method (physical vapor deposition method) such as a vacuum vapor deposition method, a sputtering method, an ion plating method, or a CVD method (chemical vapor deposition method). Is appropriately used. For example, in a vacuum evaporation method, resistance heating, high-period induction heating, electron beam heating, or the like can be used as a heating method. In addition, oxygen, nitrogen, or the like may be introduced as a reactive gas, or reactive vapor deposition using means such as ozone addition or ion assist may be used.

When a sputtering method is used, a pure metal or a target metal compound can be used as a target material. When a pure metal is used, oxygen, nitrogen or the like is introduced as a reactive gas. DC power supply,
A pulse DC power supply or a high-frequency power supply can be used.

Prior to the formation of a thin film by the above method, degassing of the substrate by heating the substrate or vacuum glow treatment of the surface of the lower layer may be performed to improve the adhesion to the lower layer.
For example, in vacuum glow processing, 1 to 10 mtorr
A high frequency is applied to the substrate under a pressure of about r to form a glow discharge, and the substrate can be processed by the generated plasma. Further, the effect can be improved by increasing the applied voltage or introducing a reactive gas such as oxygen or nitrogen.

The inorganic thin film having a surface containing a metal oxide used for the hydrophilic layer of the present invention has a thickness of 10 nm to 30 nm.
00 nm is preferred. More preferably, 20 to 1500
nm. If too thin, the retention of fountain solution decreases, giving undesired results such as a decrease in film strength, if too thick,
Since it takes time to form a thin film, it is not preferable in terms of production suitability.

The lithographic printing plate precursor of the present invention has a heat-sensitive layer of the present invention provided on a hydrophilic layer. If necessary, a water-soluble metal salt such as zinc borate may be used between the heat-sensitive layers. An inorganic undercoat layer or an organic undercoat layer can be provided. Various organic compounds are used as an organic undercoat layer component, for example, carboxymethyl cellulose, dextrin, gum arabic, phosphonic acids having an amino group such as 2-aminoethylphosphonic acid, and phenylphosphone which may have a substituent. Acids, organic phosphonic acids such as naphthylphosphonic acid, alkylphosphonic acid, glycerophosphonic acid, methylenediphosphonic acid and ethylenediphosphonic acid, optionally substituted phenylphosphoric acid, naphthylphosphoric acid, alkylphosphoric acid and glycerophosphoric acid Such as organic phosphoric acid, phenylphosphinic acid optionally having a substituent, naphthylphosphinic acid, organic phosphinic acid such as alkylphosphinic acid and glycerophosphinic acid, amino acids such as glycine and β-alanine, and triethanolamine. Hydrate such as hydrochloride -Alanine, and hydrochlorides of amines having a carboxy group, may be used by mixing two or more.

This undercoat layer can be provided by the following method. That is, a method in which a solution obtained by dissolving the above organic compound in an organic solvent such as water or methanol, ethanol, or methyl ethyl ketone or a mixed solvent thereof is coated on a hydrophilic layer, and provided by drying.
A hydrophilic layer provided on a support is immersed in a solution in which the above organic compound is dissolved in an organic solvent such as ethanol or methyl ethyl ketone or a mixed solvent thereof to absorb the compound, and then washed and dried with water or the like. To provide an organic undercoat layer. In the former method, a solution of the above organic compound having a concentration of 0.005 to 10% by weight can be applied by various methods. Further, in the latter method, the concentration of the solution is 0.01 to 20% by weight, preferably 0.05 to 5% by weight, and the immersion temperature is 20 to 90 ° C, preferably 25 to 90%.
50 ° C., and the immersion time is 0.1 second to 20 minutes, preferably 2 seconds to 1 minute. The pH of the solution used for this is adjusted to pH 1 to 12 by a basic substance such as ammonia, triethylamine, potassium hydroxide, or an acidic substance such as hydrochloric acid or phosphoric acid.
It can also be adjusted to the range. The coating amount of the undercoat layer is 2
~ 200 mg / m ² is suitable, preferably 5-10
0 mg / m ² .

[Thermosensitive Layer] The thermosensitive layer of the lithographic printing plate precursor according to the invention contains microcapsules containing a compound having a thermoreactive functional group.

As the above-mentioned heat-reactive functional group, an ethylenically unsaturated group (for example, acryloyl group,
A methacryloyl group, a vinyl group, an allyl group, etc.), an isocyanate group or a block thereof for performing an addition reaction, and a functional group having an active hydrogen atom as a reaction partner thereof (eg, an amino group, a hydroxyl group, a carboxyl group, etc.). Epoxy group for addition reaction, its reaction partner amino group, carboxyl group or hydroxyl group, carboxyl group and hydroxyl group or amino group for condensation reaction, acid anhydride and amino group or hydroxyl group for ring opening addition reaction, etc. Can be mentioned. However, a functional group that performs any reaction may be used as long as a chemical bond is formed.

The microcapsules used in the present invention are:
It contains a compound having a thermoreactive functional group. Examples of the compound having a thermoreactive functional group include a polymerizable unsaturated group, a hydroxyl group, a carboxyl group, a carboxylate group, an acid anhydride group, an amino group, an epoxy group, an isocyanate group, and a blocked isocyanate group. In the molecule.

The compound having a polymerizable unsaturated group includes:
At least one ethylenically unsaturated bond such as an acryloyl group, a methacryloyl group, a vinyl group, an allyl group;
And preferably two or more compounds. Such a compound group is widely known in the industrial field, and in the present invention, these can be used without particular limitation. These are, in chemical form, monomers, prepolymers, ie, dimers, trimers and oligomers, or mixtures thereof, and copolymers thereof.

Examples include unsaturated carboxylic acids (eg, acrylic acid, methacrylic acid, itaconic acid, crotonic acid, isocrotonic acid, maleic acid, etc.), esters thereof, and unsaturated carboxylic acid amides. Examples include esters of carboxylic acids with aliphatic polyhydric alcohols and amides of unsaturated carboxylic acids with aliphatic polyamines. Further, an addition reaction product of an unsaturated carboxylic acid ester or unsaturated carboxylic acid amide having a nucleophilic substituent such as a hydroxyl group, an amino group or a mercapto group with a monofunctional or polyfunctional isocyanate or epoxide, and a monofunctional or Dehydration condensation products with polyfunctional carboxylic acids are also preferably used. Further, an addition reaction product of an unsaturated carboxylic acid ester or amide having an electrophilic substituent such as an isocyanate group or an epoxy group with a monofunctional or polyfunctional alcohol, amine or thiol, and further, a halogen group or a tosyloxy group And the like. Substitution reaction products of an unsaturated carboxylic acid ester or amide having a leaving substituent such as a monofunctional or polyfunctional alcohol, amine or thiol are also suitable. Also, as another preferred example,
Compounds in which the above unsaturated carboxylic acid is replaced with unsaturated phosphonic acid or chloromethylstyrene can be mentioned.

Specific examples of the polymerizable compound which is an ester of an unsaturated carboxylic acid and an aliphatic polyhydric alcohol include acrylates such as ethylene glycol diacrylate, triethylene glycol diacrylate,
3-butanediol diacrylate, tetramethylene glycol diacrylate, propylene glycol diacrylate, neopentyl glycol diacrylate, trimethylolpropane diacrylate, trimethylolpropane triacrylate, trimethylolpropane tris (acryloyloxypropyl) ether, trimethylolethane Triacrylate, hexanediol diacrylate, 1,4-cyclohexanediol diacrylate, tetraethylene glycol diacrylate,
Pentaerythritol tetraacrylate, dipentaerythritol diacrylate, dipentaerythritol pentaacrylate, dipentaerythritol hexaacrylate, sorbitol triacrylate, sorbitol tetraacrylate, sorbitol pentaacrylate, sorbitol hexaacrylate, tris (acryloyloxyethyl) isocyanurate, polyester acrylate Oligomer etc. can be mentioned.

Examples of methacrylic acid esters include tetramethylene glycol dimethacrylate, triethylene glycol dimethacrylate, neopentyl glycol dimethacrylate, trimethylolpropane trimethacrylate, trimethylolethane trimethacrylate, ethylene glycol dimethacrylate, and 1,3-butanediol. Dimethacrylate, hexanediol dimethacrylate, pentaerythritol dimethacrylate, pentaerythritol trimethacrylate, pentaerythritol tetramethacrylate, dipentaerythritol dimethacrylate, dipentaerythritol hexamethacrylate, sorbitol trimethacrylate, sorbitol tetramethacrylate, bis [p- (3- Methacryloyloxy-2 Hydroxypropoxy) phenyl]
Examples thereof include dimethylmethane and bis- [p- (methacryloyloxyethoxy) phenyl] dimethylmethane.

Examples of itaconic acid esters include ethylene glycol diitaconate, propylene glycol diitaconate, 1,3-butanediol diitaconate,
Examples thereof include 1,4-butanediol diitaconate, tetramethylene glycol diitaconate, pentaerythritol diitaconate, and sorbitol tetritaconate.

Examples of crotonates include ethylene glycol dicrotonate, tetramethylene glycol dicrotonate, pentaerythritol dicrotonate,
Sorbitol tetradicrotonate and the like can be mentioned. Examples of the isocrotonic acid ester include ethylene glycol diisocrotonate, pentaerythritol diisocrotonate, and sorbitol tetraisocrotonate. Maleic esters include ethylene glycol dimaleate, triethylene glycol dimaleate, pentaerythritol dimaleate,
Sorbitol tetramalate and the like can be mentioned.

Examples of other esters include, for example, JP-B-46-27926, JP-B-51-47334,
Aliphatic alcohol esters described in JP-A-57-196231, JP-A-59-5240 and JP-A-59-196231
No. 5,241, and those having an aromatic skeleton described in JP-A-2-226149 and those containing an amino group described in JP-A-1-165613.

Specific examples of the amide monomer of the aliphatic polyamine compound and the unsaturated carboxylic acid include methylenebis-acrylamide, methylenebis-methacrylamide, 1,6-hexamethylenebis-acrylamide, 1,6- Hexamethylene bis-methacrylamide,
Examples thereof include diethylenetriaminetrisacrylamide, xylylenebisacrylamide, and xylylenebismethacrylamide. Examples of other preferred amide-based monomers include those having a cyclohexylene structure described in JP-B-54-21726.

A urethane-based addition-polymerizable compound produced by an addition reaction between an isocyanate and a hydroxyl group is also suitable.
JP-A-8-41708 discloses a polyisocyanate compound having two or more isocyanate groups in one molecule and an unsaturated monomer having a hydroxyl group represented by the following formula (A) added to one molecule. Urethane compounds containing at least two polymerizable unsaturated groups are exemplified.

Formula (A) CH ₂ ＣC (R _m ) COOCH ₂ CH (R _n ) OH (where R _m and R _n represent H or CH ₃ )

Further, urethane acrylates described in JP-A-51-37193, JP-B-2-32293, JP-B-2-16765 and JP-B-58-4 can be used.
9860, JP-B-56-17654, JP-B-62-
Urethane compounds having an ethylene oxide skeleton described in JP-A-39417 and JP-B-62-39418 are also preferable.

Further, radical polymerizable compounds having an amino structure or a sulfide structure in the molecule described in JP-A-63-277653, JP-A-63-260909 and JP-A-1-105238 are also suitable. It can be mentioned as.

Other preferred examples include polyester acrylates and epoxy resins described in JP-A-48-64183, JP-B-49-43191 and JP-B-52-30490. Examples thereof include polyfunctional acrylates and methacrylates such as epoxy acrylates obtained by reacting a resin with (meth) acrylic acid. In addition, JP-B-46-43946,
Specific unsaturated compounds described in JP-B-1-40337 and JP-A-1-40336 and vinylphosphonic acid-based compounds described in JP-A-2-25493 can also be mentioned as preferable ones. In some cases, compounds containing a perfluoroalkyl group described in JP-A-61-22048 are also preferably used. Furthermore, The Journal of the Adhesion Society of Japan, Vol. 20, No. 7, pp. 300-308 (198
Those introduced as photocurable monomers and oligomers in (4 years) can also be suitably used.

Preferred copolymers of the ethylenically unsaturated compound include allyl methacrylate copolymers. For example, an allyl methacrylate / methacrylic acid copolymer, an allyl methacrylate / ethyl methacrylate copolymer, an allyl methacrylate / butyl methacrylate copolymer, and the like can be given.

Suitable epoxy compounds include glycerin polyglycidyl ether, polyethylene glycol diglycidyl ether, polypropylene diglycidyl ether, trimethylolpropane polyglycidyl ether, sorbitol polyglycidyl ether, bisphenols or polyphenols, or hydrogenated products thereof. And polyglycidyl ether.

Preferred isocyanate compounds include tolylene diisocyanate, diphenylmethane diisocyanate, polymethylene polyphenyl polyisocyanate, xylylene diisocyanate, naphthalene diisocyanate, cyclohexane phenylene diisocyanate, isophorone diisocyanate, hexamethylene diisocyanate, cyclohexyl diisocyanate, or alcohols thereof. Alternatively, a compound blocked with an amine can be used.

Suitable amine compounds include ethylenediamine, diethylenetriamine, triethylenetetramine, hexamethylenediamine, propylenediamine, polyethyleneimine and the like.

Suitable compounds having a hydroxyl group include compounds having a terminal methylol group, polyhydric alcohols such as pentaerythritol, and bisphenols and polyphenols. Suitable compounds having a carboxyl group include pyromellitic acid, trimellitic acid, aromatic polycarboxylic acids such as phthalic acid,
Examples thereof include aliphatic polycarboxylic acids such as adipic acid. Preferred acid anhydrides include pyromellitic anhydride,
Benzophenone tetracarboxylic anhydride and the like.

As a method for microencapsulation, a known method can be applied. For example, as a method for producing microcapsules, US Pat.
U.S. Pat. No. 3,287,154, U.S. Pat. No. 3,287,154.
Nos. 38-19574, 42-446, and 42-711, a method by interfacial polymerization, a method by precipitation of a polymer shown in U.S. Pat. U.S. Pat. No. 3,914,140, U.S. Pat. No. 4,087,376 and U.S. Pat. No. 4,089,802. U.S. Pat.
Method using resorcinol-based wall forming material, US Pat.
No. 025445, a method using a wall material such as melamine-formaldehyde resin and hydroxycellulose, Japanese Patent Publication Nos. 36-9163 and 51-9079, an in situ method by monomer polymerization, and British Patent 930.
No. 422, U.S. Pat. No. 3,111,407, Spray drying method, British Patent Nos. 952807, 96707
No. 4, but not limited thereto.

The preferred microcapsule wall used in the present invention has three-dimensional crosslinking and has a property of swelling by a solvent. From such a viewpoint, the wall material of the microcapsule is preferably polyurea, polyurethane, polyester, polycarbonate, polyamide, and a mixture thereof, and particularly preferably polyurea and polyurethane. A compound having a thermoreactive functional group may be introduced into the microcapsule wall.

The average particle size of the above microcapsules is
0.01 to 20 μm is preferable, and 0.05 to
2.0 μm is more preferred, and 0.10 to 1.0 μm is particularly preferred. Within this range, good resolution and stability over time can be obtained. In such a microcapsule, the capsules may be melted by heat and united, or may not be united. In short, among the microcapsule inclusions, those that have oozed out of the capsule surface or outside the microcapsules at the time of application or those that have penetrated into the microcapsule walls may cause a chemical reaction by heat. It may react with the added hydrophilic resin or the added low molecular compound. The microcapsules may be reacted with each other by providing two or more types of microcapsules with functional groups that react with each other with different functional groups. Therefore, it is preferable from the viewpoint of image formation that the microcapsules are fused and fused by heat.
Not required.

The amount of the microcapsules added to the heat-sensitive layer is as follows:
It is preferably at least 50% by weight, more preferably 60 to 95% by weight in terms of solid content. Within this range, good sensitivity and printing durability can be obtained simultaneously with good on-press developability.

When the microcapsules are added to the thermosensitive layer, a solvent in which the inclusions dissolve and the wall material swells can be added to the microcapsule dispersion medium. Such a solvent promotes the diffusion of the encapsulated compound having a thermoreactive functional group out of the microcapsules. Such a solvent depends on the microcapsule dispersion medium, the material, wall thickness, and inclusions of the microcapsule wall, but can be easily selected from many commercially available solvents. For example, in the case of water-dispersible microcapsules composed of crosslinked polyurea and polyurethane walls, alcohols,
Preferred are ethers, acetals, esters, ketones, polyhydric alcohols, amides, amines, fatty acids and the like.

Specific compounds include methanol, ethanol, tertiary butanol, n-propanol, tetrahydrofuran, methyl lactate, ethyl lactate, methyl ethyl ketone, propylene glycol monomethyl ether, ethylene glycol diethyl ether, ethylene glycol monomethyl ether, and γ-butyl lactone. , N, N-dimethylformamide, N, N-dimethylacetamide, etc., but are not limited thereto. In addition, these solvents
Two or more kinds may be used.

A solvent which does not dissolve in the microcapsule dispersion but can be dissolved if the above-mentioned solvent is mixed can be used. The amount of addition is determined by the combination of the materials, but is usually preferably 5 to 95% by weight of the coating solution.
A more preferred range is 10 to 90% by weight, and a particularly preferred range is 15 to 85% by weight.

In the heat-sensitive layer of the present invention, since a microcapsule containing a compound having a thermoreactive functional group is used, a compound for initiating or promoting these reactions may be added as necessary. . Examples of the compound that initiates or promotes the reaction include a compound that generates a radical or a cation by heat, such as a lophin dimer, a trihalomethyl compound, a peroxide, an azo compound, a diazonium salt, or a diphenyliodonium salt. Onium salts, acylphosphines, imidosulfonates and the like. These compounds can be added in the range of 1 to 20% by weight of the solid content of the heat-sensitive layer.
Preferably it is in the range of 3 to 10% by weight. Within this range, a favorable reaction initiation or acceleration effect can be obtained without impairing the on-press developability.

The heat-sensitive layer of the present invention may contain a hydrophilic resin. The addition of the hydrophilic resin not only improves the on-press developability but also improves the film strength of the heat-sensitive layer itself. As the hydrophilic resin, those having a hydrophilic group such as hydroxyl, carboxyl, hydroxyethyl, hydroxypropyl, amino, aminoethyl, aminopropyl, carboxymethyl and the like are preferable.

Specific examples of the hydrophilic resin include gum arabic, casein, gelatin, starch derivatives, carboxymethylcellulose and its sodium salt, cellulose acetate, sodium alginate, vinyl acetate-maleic acid copolymers, styrene-maleic acid copolymers,
Polyacrylic acids and their salts, polymethacrylic acids and their salts, homopolymers and copolymers of hydroxyethyl methacrylate, homopolymers and copolymers of hydroxyethyl acrylate, homopolymers and copolymers of hydroxypropyl methacrylate, homopolymers of hydroxypropyl acrylate and Copolymers, homopolymers and copolymers of hydroxybutyl methacrylate, homopolymers and copolymers of hydroxybutyl acrylate, polyethylene glycols, hydroxypropylene polymers, polyvinyl alcohols and having a degree of hydrolysis of at least 60% by weight, preferably at least 80% by weight Hydrolyzed polyvinyl acetate, polyvinyl formal, polyvinyl butyral , May include polyvinyl pyrrolidone, homopolymers and copolymers of acrylamide, homopolymers and polymers of methacrylamide, the N- methylol acrylamide homopolymers and copolymers, and the like.

The amount of the hydrophilic resin to be added to the heat-sensitive layer is preferably 5 to 40% by weight of the solid of the heat-sensitive layer, more preferably 10 to 30% by weight.
Is more preferred. Within this range, good on-press developability and film strength can be obtained.

In the lithographic printing plate precursor according to the present invention, the light-sensitive layer or a layer adjacent thereto (a hydrophilic layer, an undercoat layer or an overcoat layer described below) contains a photothermal conversion agent to thereby provide laser light. Image recording by irradiation or the like becomes possible. The photothermal conversion agent may be any substance that absorbs the wavelength of the laser light source, and various pigments, dyes and metal fine particles can be used. In particular, 700-
It is preferably a light-absorbing substance having an absorption band in at least a part of 1200 nm.

Examples of the types of pigments include black pigments, brown pigments, red pigments, purple pigments, blue pigments, green pigments, fluorescent pigments, metal powder pigments, and polymer-bound pigments. Specifically, insoluble azo pigments, azo lake pigments, condensed azo pigments, chelated azo pigments, phthalocyanine pigments, anthraquinone pigments, perylene and perinone pigments, thioindigo pigments, quinacridone pigments, dioxazine pigments, isoindolinone pigments And quinophthalone pigments, dyed lake pigments, azine pigments, nitroso pigments, nitro pigments, natural pigments, fluorescent pigments, inorganic pigments, carbon black, and the like.

These pigments may be used without surface treatment, or may be used after surface treatment. Examples of the surface treatment include a method of surface-coating a hydrophilic resin or a lipophilic resin, a method of attaching a surfactant, and a reactive substance (eg, silica sol, alumina sol, a silane coupling agent, an epoxy compound, an isocyanate compound, etc.). A method of binding to the surface of the pigment is conceivable. The above surface treatment methods are described in "Properties and Applications of Metallic Soap" (Koshobo), "Printing Ink Technology"
(CMC Publishing, 1984) and "Latest Pigment Application Technology" (CMC Publishing, 1986).
Among these pigments, those that absorb infrared rays are preferred because they are suitable for use in lasers that emit infrared rays. As such a pigment absorbing infrared rays, carbon black is preferable. The particle size of the pigment is preferably in the range of 0.01 μm to 1 μm, and more preferably in the range of 0.01 μm to 0.5 μm.

Examples of the dye include commercially available dyes and literatures (for example, "Near-Infrared Absorbing Dyes" in "Chemical Industry", May, 1986, p. , "Development and Market Trend of Functional Dyes of the 90's", Chapter 2, Section 2.3 (1990), C.M.C.) or patents can be used. Specifically, infrared absorbing dyes such as azo dyes, metal complex salt azo dyes, pyrazolone azo dyes, anthraquinone dyes, phthalocyanine dyes, carbonium dyes, quinone imine dyes, polymethine dyes, and cyanine dyes are preferred.

Further, for example, Japanese Patent Application Laid-Open No. 58-12524
No. 6, JP-A-59-84356, JP-A-60-787
No. 87, etc .;
173696, JP-A-58-181690, methine dyes described in JP-A-58-194595, and the like;
JP-A-58-112793, JP-A-58-22479
No. 3, JP-A-59-48187, JP-A-59-739
No. 96, JP-A-60-52940, JP-A-60-63
No. 744, etc .; squarylium dyes described in JP-A-58-112792, etc .; cyanine dyes described in British Patent 434,875; and dyes described in U.S. Pat. No. 4,756,993. And cyanine dyes described in U.S. Pat. No. 4,973,572, dyes described in JP-A-10-268512, JP-A-11-23.
No. 5,883, phthalocyanine compounds.

As a dye, US Pat. No. 5,156,
No. 938 is also preferably used, and substituted arylbenzo (thio) pyrylium salts described in U.S. Pat. No. 3,881,924;
No. 42645, JP-A-58-181051, JP-A-58-220143, JP-A-59-41363, JP-A-59-84248, and JP-A-59-84248.
No. 84249, No. 59-146063, No. 59-14
No. 6061, pyranium compounds described in JP-A-59-216146, cyanine dyes described in US Pat. No. 4,283,475, pentamethine thiopyrylium salts described in U.S. Pat. 5-70
No. 2, a pyrylium compound, Eporin III-178, Epolite III-130, manufactured by Eporin Co.
Epolite III-125 and the like are also preferably used. Specific compounds are listed below.

[0096]

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[0097]

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[0098]

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[0099]

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[0100]

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[0101]

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[0102]

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[0103]

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The above-mentioned organic photothermal conversion agent can be added up to 30% by weight in the thermosensitive layer. Preferably 5
The content is 25% by weight, particularly preferably 7 to 20% by weight. Within this range, good sensitivity is obtained.

In the heat-sensitive layer of the present invention, fine metal particles can be used as a light-to-heat conversion agent. Most of the metal fine particles are light-heat converting and self-heating, but preferred metal fine particles include Si, Al, Ti, V, Cr, and M.
n, Fe, Co, Ni, Cu, Zn, Y, Zr, Mo,
Ag, Au, Pt, Pd, Rh, In, Sn, W, T
e, Pb, Ge, Re, and Sb alone or as an alloy, or fine particles of oxides or sulfides thereof. Among the metals constituting these metal fine particles, preferred metals are those which are liable to be coalesced by heat at the time of light irradiation, and have a melting point of about 1000 ° C. or less and have absorption in the infrared, visible or ultraviolet region, for example, Re, Sb, Te, Au, A
g, Cu, Ge, Pb and Sn. Particularly preferred are metal fine particles having a relatively low melting point and a relatively high absorbance to infrared rays, for example, Ag, Au, C
Among u, Sb, Ge and Pb, the most preferred elements include Ag, Au and Cu.

Also, for example, Re, Sb, Te, Au, A
g, Cu, Ge, Pb, Sn and other low melting point metal particles and self-heating metal particles such as Ti, Cr, Fe, Co, Ni, W and Ge. It may be made of a light-to-heat conversion material. Also, Ag,
It is also preferable to use a combination of a metal-type micro-piece and a metal-type micro-piece having a particularly large light absorption when made into a micro-piece such as Pt or Pd.

The particle size of these particles is preferably 10 μm.
m, more preferably 0.003 to 5 μm, particularly preferably 0.01 to 3 μm. Within this range, good sensitivity and resolution can be obtained.

In the present invention, when these metal fine particles are used as a light-to-heat conversion agent, the amount added is preferably at least 10% by weight of the solid content of the heat-sensitive layer, more preferably 2% by weight.
0% by weight or more, particularly preferably 30% by weight or more. High sensitivity is obtained within this range.

In the heat-sensitive layer of the lithographic printing plate precursor according to the invention,
Further, it can contain a low molecular compound having a functional group capable of reacting with a compound having a thermoreactive functional group contained in the microcapsule and a protective group thereof. The addition amount of these compounds is from 5% by weight to
It is preferably 40% by weight, particularly preferably 5% to 20% by weight. If the amount is less than this, the cross-linking effect is small and the printing durability becomes insufficient. Specific examples of such a compound include those similar to the specific examples of the compound having a heat-reactive functional group included in the microcapsules.

The heat-sensitive layer of the present invention may further contain various compounds other than those described above, if necessary. For example, a dye having a large absorption in the visible light region can be used as a colorant for an image in order to make it easy to distinguish between an image portion and a non-image portion after image formation. Specifically, Oil Yellow # 101, Oil Yellow # 103, Oil Pink #
312, oil green BG, oil blue BOS, oil blue # 603, oil black BY, oil black BS, oil black T-505 (all manufactured by Orient Chemical Co., Ltd.), Victoria Pure Blue, crystal violet (CI42555), methyl Violet (CI42535), ethyl violet, rhodamine B (CI145170B), malachite green (CI42000), methylene blue (CI5201)
5) etc. and dyes described in JP-A-62-293247. Also, pigments such as phthalocyanine pigments, azo pigments, and titanium oxide can be suitably used. The addition amount is preferably 0.01 to 10% by weight based on the total solid content of the heat-sensitive layer coating solution.

In the present invention, it is desirable to add a small amount of a thermal polymerization inhibitor in order to prevent unnecessary thermal polymerization of the ethylenically unsaturated compound during preparation or storage of the coating solution for the thermosensitive layer. Suitable thermal polymerization inhibitors include hydroquinone, p-methoxyphenol, di-tert-butyl-p-cresol, pyrogallol, t-butylcatechol, benzoquinone, 4,4'-thiobis (3-methyl-6-tert-butylphenol) ), 2,2'-methylenebis (4-methyl-6-t-butylphenol), N-nitroso-N-phenylhydroxylamine aluminum salt and the like. The addition amount of the thermal polymerization inhibitor is preferably about 0.01 to 5% by weight based on the weight of the total composition of the heat-sensitive layer component.

Further, if necessary, a higher fatty acid such as behenic acid or behenic acid amide or a derivative thereof is added to prevent polymerization inhibition by oxygen. It may be unevenly distributed. The amount of the higher fatty acid or derivative thereof added is preferably about 0.1 to about 10% by weight of the solid content of the heat-sensitive layer.

Further, a plasticizer can be added to the heat-sensitive layer of the present invention, if necessary, to impart flexibility to the coating film. For example, polyethylene glycol, tributyl citrate, diethyl phthalate, dibutyl phthalate,
Dihexyl phthalate, dioctyl phthalate, tricresyl phosphate, tributyl phosphate, trioctyl phosphate, tetrahydrofurfuryl oleate, and the like are used.

The heat-sensitive layer of the present invention is prepared by dispersing or dissolving each of the above-mentioned necessary components in a solvent to prepare a coating solution and coating the same. As the solvent used here, ethylene dichloride, cyclohexanone, methyl ethyl ketone, methanol, ethanol, propanol, ethylene glycol monomethyl ether, 1-methoxy-2-propanol,
2-methoxyethyl acetate, 1-methoxy-2-propyl acetate, dimethoxyethane, methyl lactate, ethyl lactate, N, N-dimethylacetamide, N, N-dimethylformamide, tetramethylurea, N-methylpyrrolidone, dimethylsulfoxide, Sulfolane, γ-
Examples thereof include, but are not limited to, butyl lactone, toluene, and water. These solvents are
Used alone or in combination. The solid content concentration of the coating solution is preferably 1 to 50% by weight.

The coating amount (solid content) of the heat-sensitive layer on the support obtained after coating and drying varies depending on the application, but is generally preferably 0.5 to 5.0 g / m ² . When the amount of coating is smaller than this range, the apparent sensitivity increases, but the film characteristics of the heat-sensitive layer that performs the function of image recording deteriorate. Various methods can be used as a method of applying. For example, bar coater coating, spin coating, spray coating, curtain coating, dip coating, air knife coating,
Examples include blade coating and roll coating.

A surfactant for improving coating properties, for example, a fluorine-based surfactant as described in JP-A-62-170950 can be added to the heat-sensitive layer coating solution. A preferable addition amount is 0.1% of the total solid content of the heat-sensitive layer.
The content is from 01 to 1% by weight, more preferably from 0.05 to 0.5% by weight.

(Overcoat Layer) In the lithographic printing plate precursor according to the invention, it is preferable to provide a water-soluble overcoat layer on the heat-sensitive layer in order to prevent the surface of the heat-sensitive layer from being stained or damaged by a lipophilic substance. The water-soluble overcoat layer used in the present invention can be easily removed at the time of printing and contains a resin selected from water-soluble organic polymer compounds. As the water-soluble organic polymer compound used herein, a film formed by coating and drying has a film-forming ability, and specifically, polyvinyl acetate (provided that the hydrolysis rate is 65%).
% Or more), polyacrylic acid, its alkali metal salt or amine salt, polyacrylic acid copolymer, its alkali metal salt or amine salt, polymethacrylic acid, its alkali metal salt or amine salt, polymethacrylic acid copolymer Coalescence, its alkali metal salt or amine salt, polyacrylamide, its copolymer, polyhydroxyethyl acrylate, polyvinylpyrrolidone, its copolymer, polyvinyl methyl ether, vinyl methyl ether / maleic anhydride copolymer, poly-2- Acrylamide-2-
Methyl-1-propanesulfonic acid, its alkali metal salt or amine salt, poly-2-acrylamido-2-methyl-1-propanesulfonic acid copolymer, its alkali metal salt or amine salt, gum arabic, cellulose derivative ( For example, carboxymethylcellulose, carboxyethylcellulose, methylcellulose and the like), modified products thereof, white dextrin, pullulan, enzymatically decomposed etherified dextrin and the like can be mentioned. Further, according to the purpose, two or more of these resins can be used in combination.

The above-mentioned water-soluble photothermal conversion agent may be added to the overcoat layer. Furthermore, in the case of aqueous solution application, a nonionic surfactant such as polyoxyethylene nonylphenyl ether and polyoxyethylene dodecyl ether can be added to the overcoat layer in order to ensure uniformity of application. . Dry coating amount of the overcoat layer, 0.1 to 2.0 g / m ² is preferred. Within this range, excellent contamination prevention and scratch prevention of the surface of the heat-sensitive layer by a lipophilic substance such as fingerprint adhesion can be prevented without impairing the on-press developability.

(Image formation and plate making) The lithographic printing plate precursor of the present invention forms an image by heat. Specifically, direct image-like recording using a thermal recording head or the like, scanning exposure using an infrared laser, high illuminance flash exposure such as a xenon discharge lamp, or infrared lamp exposure is used.
Exposure with a solid-state high-power infrared laser such as a semiconductor laser or a YAG laser that emits infrared at 200 nm is preferable.

The lithographic printing plate precursor of the present invention, which has been image-exposed, can be mounted on a printing press without any further processing, and can be printed by an ordinary procedure using ink and fountain solution. These lithographic printing plate precursors are disclosed in Japanese Patent No. 29383.
As described in No. 98, after mounting on a printing press cylinder, it can be exposed by a laser mounted on the printing press, and then developed on a printing press with dampening water and / or ink. is there. These lithographic printing plate precursors can be used for printing after development using water or an appropriate aqueous solution as a developing solution.

[0121]

The present invention will be described in more detail with reference to the following Examples, which, of course, are not intended to limit the scope of the present invention.

[Synthesis of Microcapsules] (Synthesis of microcapsules (1) encapsulating a compound having a thermoreactive functional group) As an oil phase component, 40 g of xylene diisocyanate, 10 g of trimethylolpropane diacrylate, and allyl methacrylate and butyl methacrylate were used. 10 g of copolymer (molar ratio 60/40), 0.1 g of pionin A41C (manufactured by Takemoto Yushi) and 60 g of ethyl acetate
Was dissolved. PVA205 (made by Kuraray) as an aqueous phase component
120 g of a 4% aqueous solution was prepared. The oil phase component and the aqueous phase component were emulsified at 10,000 rpm using a homogenizer. Thereafter, 40 g of water was added, and the mixture was stirred at room temperature for 30 minutes and further at 40 degrees for 3 hours. The microcapsule solution thus obtained had a solid content of 20% and an average particle size of 0.5 μm.

(Synthesis of microcapsule (2) encapsulating a compound having a thermoreactive functional group) 30 g of isophorone diisocyanate, 10 g of hexamethylene diisocyanate, 20 g of diethylene glycol diglycidyl ether as oil phase components, Pionin A41C (manufactured by Takemoto Yushi)
0.1 g was dissolved in 60 g of ethyl acetate. As a water phase component, 120 g of a 4% aqueous solution of PVA205 (manufactured by Kuraray) was prepared. The oil phase component and the water phase component were emulsified at 10,000 rpm using a homogenizer. After that, add 40
g was added and the mixture was stirred at room temperature for 30 minutes and further at 40 degrees for 3 hours. The microcapsule solution thus obtained had a solid content of 20% and an average particle size of 0.7 μm.

(Synthesis of Microcapsules (3) Encapsulating a Compound Having a Thermally Reactive Functional Group) D-
110N (manufactured by Takeda Pharmaceutical) 30g, Karenz MOI
(Manufactured by Showa Denko) 10 g of (2-methacryloyloxyethyl isocyanate), 10 g of trimethylolpropane triacrylate, 10 g of a copolymer of allyl methacrylate and butyl methacrylate (molar ratio 60/40), 0.1 g of Pionin A41C (manufactured by Takemoto Yushi) Was dissolved in 60 g of ethyl acetate. 120 g of a 4% aqueous solution of PVA205 (manufactured by Kuraray) was prepared as an aqueous phase component. The oil phase component and the water phase component were separated using a homogenizer at 10,000 rpm.
And emulsified. Thereafter, 40 g of water was added, and the mixture was stirred at room temperature for 30 minutes and further at 40 degrees for 3 hours. The microcapsule solution thus obtained had a solid content of 20% and an average particle size of 0.5 μm.

(Synthesis of Microcapsules (4) Encapsulating a Compound Having a Thermoreactive Functional Group)
110N (manufactured by Takeda Pharmaceutical) 40g, diethylene glycol diglycidyl ether 20g, pionin A41C
0.1 g (manufactured by Takemoto Yushi) was dissolved in 60 g of ethyl acetate. 120 g of a 4% aqueous solution of PVA205 (manufactured by Kuraray) was prepared as an aqueous phase component. The oil phase component and the aqueous phase component were emulsified at 10,000 rpm using a homogenizer. Thereafter, 40 g of water was added, and the mixture was stirred at room temperature for 30 minutes and further at 40 degrees for 3 hours. The microcapsule solution thus obtained has a solid content of 20% and an average particle size of 0.7%.
μm.

(Fine Particle Polymer Having No Thermally Reactive Functional Group)
-1 15g styrene, polyoxyethylene
Tylene phenol aqueous solution (concentration 9.84 × 10 ^-3mol
・ L^-1) Add 200ml and stir at 250rpm
Then, the inside of the system is replaced with nitrogen gas. Bring the solution to 25 ° C
After that, an aqueous cerium (IV) ammonium salt solution (concentration: 0.
984 × 10^-3mol·l^-1) Add 10 ml. this
At this time, an ammonium nitrate aqueous solution (concentration: 58.8 × 10^-3m
ol ・ l^-1) To adjust the pH to 1.3 to 1.4.
It was then stirred for 8 hours. Obtained in this way
The solid concentration of the liquid was 9.5%, and the average particle size was 0.4 μm.
m.

Example 1 (Formation of Support and Hydrophilic Layer) Polyethylene terephthalate having a thickness of 175 μm (thermal conductivity: 0.00046 cal)
/ Cm · sec · ° C), a corona treatment is applied to both sides, and the following coating solution is applied to both sides and heated and dried (180
C. for 30 seconds) to form an antistatic layer having a dry film thickness of 0.5 g / m ² .

(Antistatic layer coating solution) Acrylic resin aqueous dispersion 20 g (Julima ET-410, solid content 20% by weight, manufactured by Nippon Pure Chemical Co., Ltd.) Tin oxide-antimony oxide aqueous dispersion 30 g (average particle size) Diameter: 0.1 μm, 17% by weight) Polyoxyethylene nonylphenyl ether 0.6 g (Nonipol 100, manufactured by Sanyo Chemical Industries, Ltd.) Alkyl diphenyl ether disulfonate sodium salt aqueous solution 0.6 g (Sandet BL, concentration 40 weight Melamine compound 0.2 g (Sumitec Resin M-3, active ingredient concentration 80% by weight, manufactured by Sumitomo Chemical Co., Ltd.) Silica gel 20% aqueous dispersion 17 g (Snowtex C (manufactured by Nissan Chemical Industries, Ltd., average particle size: about 10 nm) ・ 42.4 g of water

Next, the following hydrophilic layer coating solution was coated on one side of the above polyethylene terephthalate, and dried by heating (100 ° C., 10 minutes) to a dry weight of 1.5.
g / m ² of a hydrophilic layer was formed.

(Hydrophilic Layer Coating Solution) 8% aqueous dispersion of titanium oxide 20% / polyvinyl alcohol 10% (titanium oxide (manufactured by Wako Pure Chemical Industries, Ltd., rutile type, average particle diameter 200 nm)) / PVA117 (Kuraray Co., Ltd.) )) = 2/1 weight ratio) 8 g of a 20% aqueous silica gel dispersion (Snowtex C (manufactured by Nissan Chemical Industries, Ltd., average particle diameter: about 10 nm)) 4.7 g of sol-gel preparation solution (the following composition) 4.7 g of poly Oxyethylene nonyl phenyl ether 0.025 g (Nonipol 100, manufactured by Sanyo Chemical Industries, Ltd.) Water 20 g

(Preparation of sol-gel preparation liquid) A liquid having the following composition was aged at room temperature for 1 hour to prepare a sol-gel preparation liquid. -8.5 g of tetraethoxysilane-1.8 g of methanol-15.0 g of water-0.015 g of phosphoric acid

(Formation of Thermosensitive Layer) A coating solution having the following composition was applied on the hydrophilic layer and dried (90 ° C., 2 minutes) to form a thermosensitive layer having a dry coating weight of 0.6 g / m ^2. As a result, a lithographic printing plate precursor was obtained.

(Thermal Layer Coating Solution 1) 25 g of dispersion liquid of microcapsule (1) synthesized above 0.5 g of polyhydroxyethyl acrylate 0.3 g of sulfate of p-diazophenylamine I-32 described in the description) 0.3 g ・ 70 g of water ・ 30 g of 1-methoxy-2-propanol

The lithographic printing plate precursor thus obtained is
After exposure with a Creo Trendsetter 3244VFS equipped with a water-cooled 40 W infrared semiconductor laser under the conditions of an output of 9 W, an external drum rotation speed of 210 rpm, a plate surface energy of 100 mJ / cm ² , and a resolution of 2400 dpi, no processing was performed. The printer was attached to a cylinder of a printing machine SOR-M, and after supplying dampening water, ink was supplied, and paper was further supplied to perform printing (fountain water used: EU-3 (Fuji Photo Film Co., Ltd.) 1% by volume and 10% by volume of isopropanol
Aqueous solution added, ink used: GEOS-G black (manufactured by Dainippon Ink and Chemicals, Inc.) In the early stage of printing, the heat-sensitive layer in the non-image area was promptly placed on a printing machine.
20,000 good prints were obtained which were removed from the plate surface, had no stain on the non-image area, and had no problem in the printing durability of the image area.

Examples 2 to 4 Example 1 was repeated except that the microcapsule dispersion in the coating solution for the thermosensitive layer was changed to the dispersions of the microcapsules (2), (3) and (4) synthesized above. In the same manner as in the above, each lithographic printing plate precursor was obtained. Next, when image exposure and printing were performed in the same manner as in Example 1, at the initial stage of printing, the heat-sensitive layer in the non-image portion was promptly removed from the printing plate on a printing press, and the stain in the non-image portion was removed. As a result, 20,000 good prints having no problem in the printing durability of the image portion were obtained.

Comparative Example 1 The procedure of Example 1 was repeated, except that the microcapsule dispersion in the heat-sensitive layer coating liquid was changed to 52.6 g of the dispersion of the synthesized fine particle polymer 1.
A lithographic printing plate precursor was obtained. Next, when image exposure and printing were performed in the same manner as in Example 1, at the beginning of printing, the heat-sensitive layer in the non-image area was immediately printed on a printing machine.
Although it was removed from the plate surface, a part of the image portion dropped off during printing due to insufficient printing durability of the image portion, and the image portion was dull, and a good printed matter was not obtained.

Example 5 A lithographic printing plate precursor was obtained in the same manner as in Example 1 except that the composition of the heat-sensitive layer coating solution was changed to the following composition. Next, when image exposure and printing were performed in the same manner as in Example 1, at the initial stage of printing, the heat-sensitive layer in the non-image portion was promptly removed from the printing plate on a printing press, and the stain in the non-image portion was removed. As a result, 20,000 good prints having no problem in the printing durability of the image portion were obtained.

(Thermal Layer Coating Solution 2) Dispersion of the microcapsule (1) synthesized above 25 g Polyacrylic acid 0.5 g (weight average molecular weight 25,000) Sorbitol triacrylate 1.0 g Light-to-heat converting agent (described in this specification) I-31) 0.3 g Sulfate of t-butyldiphenyliodonium 0.3 g Water 70 g 1-methoxy-2-propanol 30 g

Example 6 A lithographic printing plate was prepared in the same manner as in Example 5, except that the microcapsule dispersion in the thermosensitive layer coating liquid 2 was changed to the dispersion of the synthesized microcapsules (3). I got the original. Next, when image exposure and printing were performed in the same manner as in Example 1, at the initial stage of printing, the heat-sensitive layer in the non-image portion was promptly removed from the printing plate on a printing press, and the stain in the non-image portion was removed. As a result, 20,000 good prints having no problem in the printing durability of the image portion were obtained.

Example 7 A lithographic printing plate precursor was obtained in the same manner as in Example 1 except that the composition of the heat-sensitive layer coating solution was changed as follows. Next, when image exposure and printing were performed in the same manner as in Example 1, at the initial stage of printing, the heat-sensitive layer in the non-image portion was promptly removed from the printing plate on a printing press, and the stain in the non-image portion was removed. As a result, 20,000 good prints having no problem in the printing durability of the image portion were obtained.

(Thermal Layer Coating Solution 3) Dispersion of the synthesized microcapsule (2) 25 g Polyacrylic acid 0.5 g (weight average molecular weight 25,000) Diethylene triamine 1.0 g Light-to-heat converting agent (I- described in the present specification) 31) 0.3 g t-butyldiphenyliodonium sulfate 0.3 g water 70 g 1-methoxy-2-propanol 30 g

[Example 8] The microcapsule dispersion in the thermosensitive layer coating solution 3 was synthesized as described above.
Except for changing to the dispersion of (4), in the same manner as in Example 7,
A lithographic printing plate precursor was obtained. Next, when image exposure and printing were performed in the same manner as in Example 1, at the beginning of printing, the heat-sensitive layer in the non-image area was immediately printed on a printing machine.
20,000 good prints were obtained which were removed from the plate surface, had no stain on the non-image area, and had no problem in the printing durability of the image area.

Examples 9 to 16 Except that the formation of the hydrophilic layer was changed as described below, the respective lithographic printing plate precursors were obtained in the same manner as in Examples 1 to 8, respectively. Next, when image exposure and printing were performed in the same manner as in Example 1, at the beginning of printing, the heat-sensitive layer in the non-image area was immediately printed on a printing machine.
20,000 good prints were obtained which were removed from the plate surface, had no stain on the non-image area, and had no problem in the printing durability of the image area.

(Formation of Hydrophilic Layer) A batch type sputtering film forming apparatus (CFS-1 manufactured by Shibaura Eletech Co., Ltd.) is formed on the antistatic layer.
0-EP70), a silicon oxide film was formed to a thickness of 100 nm under the following conditions to form a hydrophilic layer.

(Batch type sputtering film forming conditions) Target material: silicon oxide Atmosphere: argon Film forming pressure: 5 mtorr Power: RF1 kW (power supply is JRF-3000 manufactured by JEOL Ltd.)

Before the film formation, the surface of the antistatic layer was glow-treated under the following conditions. (Glow processing conditions) Atmosphere: Argon Processing pressure: 5.0 mtorr Power: Rf3 kW (Power supply: JRF-3000 manufactured by JEOL Ltd.) Time: 2.5 minutes

Comparative Example 2 A heat-sensitive layer was formed on the following aluminum support in the same manner as in Example 1 to obtain a lithographic printing plate precursor. Next, when image exposure and printing were performed in the same manner as in Example 1, the heat-sensitive layer in the non-image area was promptly removed from the plate surface on the printing press at the beginning of printing, Due to insufficient printability, a part of the image portion dropped off during printing, and the image portion was soaked that a good printed matter could not be obtained.

(Preparation of aluminum support) 0.01% by weight of copper and 0.1% by weight of titanium were added to 99.5% by weight of aluminum.
JIS A1050 aluminum material containing 0.3% by weight of iron, 0.3% by weight of iron, and 0.1% by weight of silicon (thermal conductivity of 0.1%).
48 cal / cm · sec · ° C.) of a 0.24 mm-thick rolled plate was prepared by mixing a 400-mesh aqueous suspension of pumicestone (manufactured by Kyoritsu Ceramics) with a 20% by weight aqueous suspension and a rotating nylon brush (6.1).
0-nylon) and the surface is grained,
Washed well with water. This was immersed in a 15% by weight aqueous sodium hydroxide solution (containing 4.5% by weight of aluminum), etched so that the amount of aluminum dissolved was 5 g / m ² , and washed with running water. Further, it is neutralized with 1% by weight nitric acid, and then in a 0.7% by weight aqueous nitric acid solution (containing 0.5% by weight of aluminum), a rectangular wave having a voltage of 10.5 volts at the anode and 9.3 volts at the cathode. Alternating waveform voltage (current ratio r = 0.9
0, a current waveform described in Examples of JP-B-58-5796), and an electrolytic surface roughening treatment was performed at an anode electricity of 160 clones / dm ² . After washing with water,
After immersion in an aqueous solution of sodium hydroxide by weight and etching so that the amount of aluminum dissolved becomes 1 g / m ² ,
Washed with water. Next, it was immersed in a 30% by weight aqueous sulfuric acid solution at 50 ° C., desmutted, and washed with water. In addition, 35 ° C
A porous anodic oxide film was formed in a 20% by weight aqueous sulfuric acid solution (containing 0.8% by weight of aluminum) using a direct current. That is, electrolysis is performed at a current density of 13 A / dm ² ,
The anodic oxide film weight was adjusted to 2.7 g / m ² by adjusting the electrolysis time. This support was washed with water, immersed in a 0.2% by weight aqueous solution of sodium silicate at 70 ° C. for 30 seconds, washed with water and dried.

Example 17 A lithographic printing plate precursor was obtained in the same manner as in Example 1 except that the following undercoat layer was formed on the hydrophilic layer. Next, when image exposure and printing were performed in the same manner as in Example 1, at the initial stage of printing, the heat-sensitive layer in the non-image portion was promptly removed from the printing plate on a printing press, and the stain in the non-image portion was removed. As a result, 20,000 good prints having no problem in the printing durability of the image portion were obtained.

(Formation of Undercoat Layer) The following undercoat layer coating solution was applied on the hydrophilic layer and dried by heating (100 ° C., 1 minute) to give a dry coating amount of 0.05 g / m ² . A layer was formed.

(Coating liquid for undercoat layer) 1 g of gum arabic 1000 g of water

Example 18 The procedure of Example 1 was repeated, except that the following overcoat layer was formed on the heat-sensitive layer.
A lithographic printing plate precursor was obtained. Next, when image exposure and printing were performed in the same manner as in Example 1, at the beginning of printing, the overcoat layer and the heat-sensitive layer in the non-image portion were promptly removed from the plate surface on a printing press, and the non-image 20,000 sheets of good printed matter having no stains in the image area and no problem in the printing durability of the image area were obtained.

(Formation of Overcoat Layer) On the heat-sensitive layer,
Apply the following overcoat layer coating solution and heat dry (100
C. for 2 minutes) to obtain a dry coating weight of 0.3 g / m ^2.
Was formed to obtain a lithographic printing plate precursor.

(Coating solution for overcoat layer)-1 g of gum arabic-0.025 g of polyoxyethylene nonylphenyl ether-19 g of water

Example 19 A lithographic printing plate precursor was obtained in the same manner as in Example 1 except that both surfaces of polyethylene terephthalate were subjected to sandblasting so that the center line average roughness Ra was 0.3 μm. Was. Next, when image exposure and printing were performed in the same manner as in Example 1, at the initial stage of printing, the heat-sensitive layer in the non-image portion was promptly removed from the printing plate on a printing press, and the stain in the non-image portion was removed. As a result, 20,000 good prints having no problem in the printing durability of the image portion were obtained.

[0156]

As described above, the lithographic printing plate precursor according to the present invention has good on-press development in which an image can be scanned and exposed by an infrared laser beam and then directly mounted on a printing machine for printing. , High sensitivity, high printing durability, and no stain on printing.

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2H025 AA12 AA14 AB03 AC08 AD01 BH03 DA02 DA10 DA19 DA36 2H084 AA14 AA38 AE05 BB04 BB16 CC05 2H096 AA06 BA01 BA20 CA20 EA04 EA23 2H114 AA04 AA22 DA12 DA12 DA12 DA38 DA52 DA56 DA59 DA73 DA78 EA03 EA05 FA16 GA34 GA38

Claims (5)

[Claims] 1. A lithographic printing plate precursor comprising: a plastic film support; and a hydrophilic layer and a heat-sensitive layer containing microcapsules containing a compound having a thermoreactive functional group. . 2. The lithographic printing plate precursor according to claim 1, wherein the hydrophilic layer contains an inorganic matrix formed by sol-gel conversion. 3. The method according to claim 1, wherein the hydrophilic layer is an inorganic thin film having a surface containing a metal oxide.
The lithographic printing plate precursor described in. 4. The lithographic printing plate precursor according to claim 1, further comprising a water-soluble overcoat layer on the heat-sensitive layer. 5. A lithographic printing plate precursor having a hydrophilic layer and a heat-sensitive layer containing microcapsules encapsulating a compound having a thermoreactive functional group on a plastic film support in this order by laser light. A plate making and printing method for a lithographic printing plate, comprising image-exposing and directly attaching to a printing machine for printing, or after attaching to a printing machine, image-exposing with a laser beam on the printing machine and printing as it is.