JP2000247051A - Original plate for direct lithography printing - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an original plate for direct lithography printing capable or printing many printed sheets of a clear image without scumming and without lack, strain or the like of the image or particularly an original plate for direct lithography printing adapted to electrostatic discharge type ink jet type engraving using an oily ink. SOLUTION: The original plate for direct lithography printing comprises an image receptive layer containing at least a bonding resin containing a composite material of metal hydroxide compound particles represented by the formula M(OH)1 (wherein M is a metallic atom of Mg, Ba, Al, Ti, Zn, Cu, Ni, Sn, Co, Ge, Fe or La, and (x) is a valence of the metal M), and an organic polymer containing a resin having a siloxane bond-containing resin connected with Si through an oxygen atom and a group for forming a hydrogen bond to the resin on a water-resisting support.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lithographic printing original plate for direct drawing, and more particularly to a lithographic printing original plate for providing a lithographic printing plate capable of printing a large number of clear printed images without background contamination. .

[0002]

2. Description of the Related Art Lithographic printing plates currently used mainly in the field of light printing include (1) a water-resistant support,
(2) A direct-printing type master provided with a hydrophilic image-receiving layer, (2) a non-image area after directly making a plate on a water-resistant support provided with an image-receiving layer (lipophilic) containing zinc oxide Is subjected to a desensitizing treatment with a desensitizing solution to form a printing plate. (3) An electrophotographic light-sensitive material having a photoconductive layer containing photoconductive zinc oxide on a water-resistant support is used as an original plate. , The non-image part after image formation,
A printing plate is prepared by desensitizing with a desensitizing solution, and (4) a silver salt photographic original plate in which a silver halide emulsion layer is provided on a water-resistant support.

With the recent development of office equipment and the development of OA, in the printing field, various methods such as an electrophotographic printer, a thermal transfer printer, and an ink jet printer have been applied to the above-mentioned (1) original plate for direct drawing type lithographic printing. There is a demand for an offset lithographic printing method in which a printing plate is directly prepared without performing a specific process for making a printing plate (that is, image formation) and making a printing plate.

[0004] A conventional direct drawing type lithographic printing plate precursor is provided with a surface layer serving as an image receiving layer on both sides of a support such as paper via a back layer and an intermediate layer. Back layer or intermediate layer is PV
It is composed of a water-soluble resin such as A or starch, a water-dispersible resin such as a synthetic resin emulsion, and a pigment. The image receiving layer is usually composed of an inorganic pigment, a water-soluble resin and a waterproofing agent.

[0005] Examples of inorganic pigments include kaolin, clay, talc, calcium carbonate, silica, titanium oxide, zinc oxide, barium sulfate, and alumina. Examples of the water-soluble resin include polyvinyl alcohol (PVA), modified PVA such as carboxy PVA, starch and derivatives thereof, carboxymethyl cellulose, cellulose derivatives such as hydroxyethyl cellulose, casein, gelatin, polyvinylpyrrolidone, and vinyl acetate-crotonic acid. Water-soluble resins such as a polymer and a styrene-maleic acid copolymer combination are exemplified.

Glyoxal is used as a waterproofing agent,
Examples include initial condensates of aminoplasts such as melamine formaldehyde resins and urea formaldehyde resins, modified polyamide resins such as methylolated polyamide resins, polyamide / polyamine / epichlorohydrin adducts, polyamide epichlorohydrin resins, and modified polyamide polyimide resins. It is also known that ammonium chloride, a crosslinking catalyst for a silane coupling agent, and the like can be used in combination.

Further, as a binder used in the image receiving layer of the direct drawing type lithographic printing plate precursor, the binder has a functional group which generates a carboxyl group, a hydroxyl group, a thiol group, an amino group, a sulfone group or a phosphono group by decomposition. A resin which contains a functional group which is cured by heat / light and is crosslinked in advance is used (JP-A-1-226395 and JP-A-1-269593).
And JP-A-1-288488), a combination of the above functional group-containing resin and a heat / photo-curable resin (Japanese Unexamined Patent Publication No. 1-2665).
No. 46, No. 1-275191, No. 1-309068), and the above-mentioned functional group-containing resin is used in combination with a crosslinking agent (JP-A Nos. 1-267093, 1-271292, 1).
Accordingly, improvements in the hydrophilicity of the non-image area, improvement in the film strength of the image receiving layer, and further improvement in the printing durability have been studied.

The image receiving layer contains resin particles having a fine particle diameter of 1 μm or less containing hydrophilic groups such as a carboxyl group, a sulfo group, and a phosphono group, together with an inorganic pigment and a binder (Japanese Patent Application Laid-open No. No. 4-201387, 4-2
No. 23196) or fine resin particles containing a functional group capable of generating a hydrophilic group as described above by decomposition (Japanese Patent Application Laid-Open Nos. 4-319492 and 4-353).
No. 495, No. 5-119545, No. 5-58071
To improve the hydrophilicity of the non-image area.

However, the conventional printing plate thus obtained increases the hydrophobicity by increasing the amount of a water-proofing agent or using a hydrophobic resin in order to improve the printing durability. In this case, the printing durability is improved, but the hydrophilicity is reduced to cause printing stains. On the other hand, if the hydrophilicity is improved, the water resistance is deteriorated and the printing durability is reduced. In particular, in a use environment at a high temperature of 30 ° C. or more, the surface layer is dissolved in immersion water used for offset printing, and there are drawbacks such as a decrease in printing durability and generation of printing stains. Furthermore, in the case of a direct drawing type lithographic printing plate, an oil-based ink or the like is drawn on the image receiving layer as an image portion. If the adhesiveness between the receiving layer of the printing plate and the oil-based ink is not good, the non-image portion is used. However, even if the above-mentioned printing stains are not generated as described above, the problem that the oily ink in the image area is lost at the time of printing and the printing durability is reduced as a result is still sufficiently solved. Has not been reached.

On the other hand, as the image receiving layer, a plate composed of a hydrophilic layer containing titanium oxide, polyvinyl alcohol and hydrolyzed tetramethoxysilane or tetraethoxysilane (JP-A-3-42679, 10-268583, etc.) is mentioned. Can be However, when actually making a plate and printing it as a printing plate, the printing durability of the image was insufficient.

[0011]

SUMMARY OF THE INVENTION The present invention is to solve the above-mentioned problems of the conventional direct drawing type lithographic printing plate precursor. SUMMARY OF THE INVENTION An object of the present invention is to provide an excellent direct drawing type lithographic printing plate precursor that does not generate not only uniform background stains but also point-like background stains as an offset printing plate. Another object of the present invention is to provide a direct drawing type lithographic printing plate precursor that provides a printing plate capable of printing a large number of clear images without any background stains and without any missing or distorted images. .

[0012]

The above object is achieved by the following constitution. (1) On a water-resistant support, an average particle size of 0.01 to 5 μm
And a composite of a metal hydroxide compound particle represented by the following general formula (I) and a siloxane bond-containing resin in which Si is connected via an oxygen atom and an organic polymer containing a group capable of forming a hydrogen bond with the resin. A direct drawing type lithographic printing plate precursor having an image receiving layer containing at least a binder resin comprising:

General formula (I) M (OH) _x [In the general formula (I), M is Mg, Ba, Al, Ti, Z
represents a metal atom of n, Cu, Ni, Sn, Co, Ge, Fe or La. x represents the valence of the metal M. ]

(2) The resin according to (1), wherein the resin containing a siloxane bond in the image receiving layer is a polymer obtained by hydrolytic polycondensation of at least one silane compound represented by the following general formula (II). ) The direct-printing type lithographic printing plate described in (1).

General formula (II) (R ⁰ ) _n Si (Y) _4-n [In general formula (II), R ⁰ represents a hydrogen atom, a hydrocarbon group or a heterocyclic group. Y is a hydrogen atom, a halogen atom, -O
R ¹ , —OCOR ² or —N (R ³ ) (R ⁴ ) (R ¹ and R ² each represent a hydrocarbon group; R ³ and R ⁴ may be the same or different; Represents a hydrogen group). n represents 0, 1 or 2. However, the number of Si atoms is 3
Excludes cases where more than one hydrogen atom is bonded. ]

(3) The original plate for direct drawing type lithographic printing as described in (1) or (2) above, wherein the smoothness of the surface of the image receiving layer is 30 (sec / 10 cc) or more in Beck smoothness. .

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail. The present invention relates to a metal hydroxide compound particle made of a specific metal, a siloxane bond-containing resin in which Si is connected via an oxygen atom, and an organic material containing a specific polar group having a hydrogen bonding property on a water-resistant support. This is a direct-drawing lithographic printing plate precursor provided with an image-receiving layer having a hydrophilic surface containing at least a binder resin containing a complex with a polymer.

The inorganic particles used in the image receiving layer of the present invention include:
A metal hydroxide compound represented by the above general formula (I).
Preferably, M is Al, Ti, Zn, Cu, Ni, Sn
Or Co. The average particle size of the metal hydroxide compound particles used in the present invention is suitably from 0.01 to 5 μm, and preferably from 0.02 to 3 μm. Within this range, favorable smoothness of the surface of the image receiving layer and image strength after image formation can be obtained, and printing ink stains on the non-image portion do not occur.

These metal hydroxide compounds are produced by a conventionally known method. For example, "Chemical Experiment Course 9, Synthesis and Purification of Inorganic Compounds", edited by The Chemical Society of Japan, published by Maruzen Co., Ltd. (1958)
Year), "Chemical Dictionary 5" 18-
39, Kyoritsu Shuppan Co., Ltd. (1963) and the like. These compounds are also marketed as commercial products. For example, “Coloring Material Handbook” edited by The Coloring Materials Association, page 250, published by Asakura Shoten (1989), “Paints and Pigments” 184 by Akira Misono, etc. Page, published by Nikkan Kogyo Shimbun (1960) and the like.

The binder resin provided to the image receiving layer of the present invention includes a siloxane bond-containing resin in which Si is connected via an oxygen atom (hereinafter, abbreviated as a siloxane polymer).
It is a resin comprising a complex of the siloxane bond-containing resin and an organic polymer having a group capable of forming a hydrogen bond. The “composite of a siloxane polymer and an organic polymer” is used to include a sol-like substance and a gel-like substance.

The siloxane polymer refers to a polymer mainly containing a bond composed of "oxygen atom-silicon atom-oxygen atom". Preferably, the polymer has a substituent in the main chain and / or a hydroxyl group at a terminal of the main chain. Further, it contains a hydrocarbon group as required. Thereby, according to the combination with the inorganic particles and the organic polymer used together,
The formation of a uniform film, the close contact of the image area, and the like can be adjusted.

The siloxane polymer of the present invention is preferably a polymer obtained by hydrolytic polycondensation of the silane compound represented by the general formula (II). here,
Hydrolytic polycondensation is a reaction in which a hydrolyzable group repeatedly undergoes hydrolysis and condensation under acidic or basic conditions to polymerize, thereby generating a hydroxyl group. The above silane compounds can be used alone or in combination of two or more.

Next, the silane compound represented by the general formula (II) will be described in detail. R ⁰ in the general formula (II) is
Preferably, a hydrogen atom, a linear or branched alkyl group having 1 to 12 carbon atoms which may be substituted, for example, a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group,
A hexyl group, a heptyl group, an octyl group, a nonyl group, a decyl group, a dodecyl group and the like; groups that can be substituted with these groups include a halogen atom (a chlorine atom, a fluorine atom, a bromine atom), a hydroxy group, a thiol group, and a carboxy group. Group, sulfo group, cyano group, epoxy group, -OR 'group (R' is a hydrocarbon group such as methyl group, ethyl group, propyl group, butyl group, hexyl group, heptyl group, octyl group, decyl group, propenyl group Group, butenyl group, hexenyl group, octenyl group, 2-hydroxyethyl group, 3-chloropropyl group, 2-cyanoethyl group, N, N-dimethylaminoethyl group, 2-bromoethyl group, 2- (2-methoxyethyl) Oxyethyl group, 2-methoxycarbonylethyl group, 3-carboxypropyl group, benzyl group, etc.), -OCOR 'group, -C OR 'group, -COR'
A group, -N (R ") (R") (R "represents the same content as a hydrogen atom or the aforementioned R 'and may be the same or different), a -NHCONHR' group, a -NHCOOR 'group,-
Si (R ′) ₃ group, —CONHR ″ group, —NHCOR ′ group, etc. 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, etc.) Examples of the group substituted with these groups include those having the same contents as the groups substituted with the above-mentioned alkyl group, and a plurality of groups may be substituted), and a group having 7 to 14 carbon atoms may be substituted. Good aralkyl groups (for example, benzyl group, phenethyl group, 3-phenylpropyl group, naphthylmethyl group, 2-naphthylethyl group, etc .; the groups substituted by these groups are the same as the groups substituted by the alkyl groups. Of the contents of
Alicyclic groups having 5 to 10 carbon atoms which may be substituted (for example, cyclopentyl group, cyclohexyl group, 2-cyclohexylethyl group, 2-cyclopentylethyl group, norbornyl group, adamantyl group) etc,
Examples of the group to be substituted with these groups include those having the same contents as the substituents of the above-mentioned alkyl group, and a plurality of groups may be substituted, and an optionally substituted aryl group having 6 to 12 carbon atoms ( For example, a phenyl group or a naphthyl group, examples of the substituent include those having the same content as the group substituted with the alkyl group, and a plurality of the groups may be substituted.)

Alternatively, a condensed heterocyclic group containing at least one atom selected from the group consisting of a nitrogen atom, an oxygen atom and a sulfur atom (for example, as a hetero ring, a pyran ring, a furan ring, a thiophene ring, a morpholine Ring, pyrrole ring, thiazole ring, oxazole ring, pyridine ring, piperidine ring, pyrrolidone ring, benzothiazole ring, benzoxazole ring, quinoline ring, tetrahydrofuran ring, etc., which may contain a substituent. The same contents as the substituents in the alkyl group are mentioned, and plural substituents may be used).

Y is preferably a halogen atom (representing a fluorine atom, a chlorine atom, a bromine atom or an iodine atom), --O
R ¹ , —OCOR ² or —N (R ³ ) (R ⁴ ).

In the —OR ¹ group, R ¹ has 1 to 10 carbon atoms.
Which may be substituted (for example, methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, propenyl, butenyl, heptenyl) Hexenyl, octenyl, decenyl, 2-hydroxyethyl, 2-hydroxypropyl, 2-methoxyethyl, 2- (methoxyethyloxy) ethyl, 2-
(N, N-diethylamino) ethyl group, 2-methoxypropyl group, 2-cyanoethyl group, 3-methyloxypropyl group, 2-chloroethyl group, cyclohexyl group, cyclopentyl group, cyclooctyl group, chlorocyclohexyl group, methoxycyclohexyl group Benzyl, phenethyl, dimethoxybenzyl, methylbenzyl, bromobenzyl, etc.).

In the --OCOR ² group, R ² is an aliphatic group having the same contents as R ¹ or an aromatic group having 6 to 12 carbon atoms which may be substituted (aromatic groups in the aforementioned R ⁰ And the same as those exemplified for the aryl group). −
In the N (R ³ ) (R ⁴ ) group, R ³ and R ⁴ may be the same or different from each other, and are each a hydrogen atom or a carbon atom having 1 to 1 carbon atoms.
0 optionally substituted aliphatic group (for example, the above-mentioned -OR
It represents an the like) the same contents as ¹ group R ¹ in. 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, but are not limited to, the following.

Methyltrichlorosilane, methyltribromosilane, methyltrimethoxysilane, methyltriethoxysilane, methyltriisopropoxysilane, methyltri-t-butoxysilane, ethyltrichlorosilane, ethyltribromosilane, ethyltrimethoxysilane, ethyltrimethoxysilane Ethoxysilane, ethyltriisopropoxysilane, 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, phenyltrichlor Silane, phenyltribromosilane, phenyltrimethoxysilane, phenyltriethoxysilane, phenyltriisopropoxysilane, phenyltri-t-butoxysilane,

Tetrachlorosilane, tetrabromosilane, tetramethoxysilane, tetraethoxysilane, tetraisopropoxysilane, tetrabutoxysilane, dimethoxydiethoxysilane, dimethyldichlorosilane,
Dimethyldibromosilane, dimethyldimethoxysilane,
Dimethyldiethoxysilane, diphenyldichlorosilane, diphenyldibromosilane, diphenyldimethoxysilane, diphenyldiethoxysilane, phenylmethyldichlorosilane, phenylmethyldibromosilane, phenylmethyldimethoxysilane, phenylmethyldiethoxysilane, triethoxyhydrosilane , Tribromohydrosilane, trimethoxyhydrosilane, isopropoxyhydrosilane, tri-t-butoxyhydrosilane, vinyltrichlorosilane, vinyltribromosilane, vinyltrimethoxysilane, vinyltriethoxysilane, vinyltriisopropoxysilane, vinyltri-t-butoxysilane, Trifluoropropyltrichlorosilane, trifluoropropyltribromosilane, trifluoropropyltrimethoxysila , Trifluoropropyl triethoxysilane, trifluoropropyl triisopropoxysilane, trifluoropropyl tri t- butoxysilane,

Γ-glycidoxypropylmethyldimethoxysilane, γ-glycidoxypropylmethyldiethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-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-butoxin lan, β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, β- ( 3,4
-Epoxycyclohexyl) ethyltriethoxysilane, and the like.

General formula (II) for use in the image receiving layer of the present invention
Together with the silane compound represented by Ti, Zn, Sn,
A metal compound that can be formed into a film by a sol-gel method, such as Zr or Al, can be used in combination. As the metal compound used,
For example, Ti (OR ⁵ ) ₄ (R ⁵ represents a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, etc .; the same applies hereinafter), TiCl ₄ , Zn (OR ⁵ ) ₂ , Zn (C
H ₃ COCHCOCH ₃ ) ₂ , Sn (OR ⁵ ) ₄ , Sn (CH ₃
COCHCOCH ₃ ) ₄ , Sn (OCOR ⁵ ) ₄ , SnC
l ₄ , Zr (OR ⁵ ) ₄ , Zr (CH ₃ COCHCOC
H ₃ ) ₄ , Al (OR ⁵ ) _{3 and the} like.

Next, the organic polymer used in the present invention will be described. The organic polymer used in the present invention,
It has a “group capable of forming a hydrogen bond with a siloxane bond-containing resin”. Such a group preferably includes at least one bond selected from an amide bond (including a carboxamide bond and a sulfonamide bond), a urethane bond and a ureido bond, and a hydroxyl group.

The organic polymer has, as a repeating unit component, at least one group capable of forming a hydrogen bond with the siloxane bond-containing resin (hereinafter, also simply referred to as a specific bonding group of the present invention) in the main chain of the polymer and / or And those contained in the side chain. Preferably, as a repeating unit ^{component, -N (R 11) CO -} , - N (R 11) SO 2 -, - N
Examples include a component in which at least one type of bond selected from HCONH- and -NHCOO- is present in the main chain and / or side chain of the polymer, and / or a component containing an -OH group. R ¹¹ in the amide bond represents a hydrogen atom or an organic residue, and examples of the organic residue include those having the same contents as the hydrocarbon group and the heterocyclic group in R ⁰ in formula (II). .

The polymer main chain contains the specific bonding group of the present invention.
The polymer having -N (R ¹¹) CO-bond or
Is -N (R¹¹) SO_TwoAmide resin having a bond, -N
Ureido resin having HCON-bond, -NHCOO-
A urethane resin containing a bond is exemplified.

Examples of the diamines and dicarboxylic acids or disulfonic acids used in the production of the amide resin, the diisocyanates used for the ureide resin, and the diols used for the urethane resin include, for example, "Polymer Data Handbook-"Basics-"Chapter I (published by Baifukan) (1
986), Shinzo Yamashita, Tosuke Kaneko, "Crosslinking Agent Handbook", Taiseisha, 1981, and the like.

Examples of other polymers having an amide bond include a polymer having a repeating unit represented by the following general formula (III), an N-acylated polyalkyleneimine, and polyvinylpyrrolidone and its derivatives.

[0039]

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In the formula (III), Z ¹ is -CO-, -SO _2-
Or represents -CS-. R ²⁰ has the same content as R ⁰ in formula (II). r ¹ is a hydrogen atom or an alkyl group having 1 to 6 carbon atoms (for example, a methyl group, an ethyl group, a propyl group,
Butyl, pentyl, hexyl, etc.). r ¹ may be the same or different. p represents an integer of 2 or 3.

Among the polymers containing a repeating unit represented by the general formula (III), the polymer in which Z ¹ represents —CO— and p represents 2 is obtained by using an oxazoline optionally having a substituent as a catalyst. It is obtained by ring-opening polymerization in the presence. Examples of the catalyst include sulfates and sulfonates such as dimethyl sulfate and alkyl p-toluenesulfonate; alkyl halides such as alkyl iodide (eg, methyl iodide); metal fluorides among Friedel-Crafts catalysts; Acids such as sulfuric acid, hydrogen iodide and p-toluenesulfonic acid, and oxazolinium salts which are salts of these acids with oxazoline can be used. This polymer may be a homopolymer or a copolymer. Further, a copolymer in which this polymer is grafted to another polymer may be used.

Specific examples of oxazolines include, for example,
2-oxazoline, 2-methyl-2-oxazoline, 2
-Ethyl-2-oxazoline, 2-propyl-2-oxazoline, 2-isopropyl-2-oxazoline, 2-
Butyl-2-oxazoline, 2-dichloromethyl-2-
Oxazoline, 2-trichloromethyl-2-oxazoline, 2-pentafluoroethyl-2-oxazoline, 2
-Phenyl-2-oxazoline, 2-methoxycarbonylethyl-2-oxazoline, 2- (4-methylphenyl) -2-oxazoline, 2- (4-chlorophenyl)
-2-oxazoline and the like. Preferred oxazolines include 2-oxazoline, 2-methyl-2-oxazoline, 2-ethyl-2-oxazoline, and the like. One or two or more of such oxazoline polymers can be used.

For other polymers having a repeating unit represented by the general formula (III), thiazoline, 4,5-dihydro-1,3-oxazine or 4,5-dihydro-1,3-thiazine is used instead of oxazoline. Can be obtained similarly.

As the N-acylated polyalkyleneimine, a carboxylic acid amide containing -N (CO-R ²⁰ )-obtained by a polymer reaction with a carboxylic acid halide or a sulfonyl halide can be used. -N obtained by molecular reaction
(SO ₂ —R ²⁰ ) —- containing sulfonamide compound (where,
R ²⁰ has the same meaning as R ²⁰ in formula (III)) can be mentioned.

The polymer containing the specific bonding group of the present invention in the side chain of the polymer contains, as a main component, a component containing at least one type of bonding group selected from the specific bonding group. Things. Examples of such components include acrylamide, methacrylamide, crotonamide, vinylacetamide, and the following compounds. However, the present invention is not limited to these.

[0046]

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[0047]

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On the other hand, the hydroxyl-containing organic polymer may be any of a natural water-soluble polymer, a semi-synthetic water-soluble polymer, and a synthetic polymer. Polymer Compound I ", published by Asakura Shoten (196
0), Business Development Center Publishing Division, “Water-Soluble Polymer / Water-Dispersible Resin Comprehensive Technical Documents”, Business Development Center Publishing Division (1981), Nagatomo Shinji, “Applications and Markets of New Water-Soluble Polymers” ( Published by CMC Corporation (1988), "Development of Functional Cellulose" Published by CMC Corporation (1985)
Year)).

For example, natural and semi-synthetic polymers include cellulose, cellulose derivatives (cellulose esters; cellulose nitrate, cellulose sulfate, cellulose acetate, cellulose propionate, cellulose succinate, cellulose butyrate, cellulose acetate succinate, acetate acetate). Cellulose ethers such as cellulose butyrate and cellulose acetate phthalate; methyl cellulose, ethyl cellulose, cyanoethyl cellulose, carboxymethyl cellulose, hydroxyethyl cellulose, hydroxypropyl cellulose, ethyl hydroxyethyl cellulose, hydroxypropyl methyl cellulose, carboxymethyl hydroxyethyl cellulose, etc.), starch, starch derivatives ( Oxidized starch, esterified starches; nitric acid, sulfuric acid, phosphoric acid, acetic acid, propion , Butyric acid, esterified products such as succinic acid, etherified starches; derivatives such as methylated, ethylated, cyanoethylated, hydroxyalkylated, carboxymethylated), alginic acid, pectin, carrageenan, tamarind gum, natural gums ( Gum arabic, guar gum, locust bean gum, gum tragacanth, xanthan gum), pullulan, dextran, casein, gelatin, chitin, chitosan and the like.

Examples of the synthetic polymer include polyvinyl alcohol, polyalkylene glycol (polyethylene glycol, polypropylene glycol, (ethylene glycol / propylene glycol) copolymer, etc.), allyl alcohol copolymer, and acrylic containing at least one hydroxyl group. Polymers or copolymers of acid esters or methacrylic esters (for example, 2
-Hydroxyethyl group, 3-hydroxypropyl group,
2,3-dihydroxypropyl group, 3-hydroxy-2
-Hydroxymethyl-2-methylpropyl group, 3-hydroxy-2,2-di (hydroxymethyl) propyl group,
Polyoxyethylene group, polyoxypropylene group,
Etc.), N-substituted polymers or copolymers of acrylamide or methacrylamide (for example, monomethylol group, 2-hydroxyethyl group, 3-
Hydroxypropyl group, 1,1-bis (hydroxymethyl) ethyl group, 2,3,4,5,6-pentahydroxypentyl group, etc.). However, the synthetic polymer is not particularly limited as long as it has at least one hydroxyl group in the side chain substituent of the repeating unit.

The weight average molecular weight of the organic polymer used in the image receiving layer of the present invention is preferably from 10 ³ to 10 ⁶ , more preferably from 5 × 10 ³ to 4 × 10 ⁵ .

In the composite of the siloxane polymer and the organic polymer of the present invention, the ratio of the siloxane polymer to the organic polymer can be selected in a wide range, but preferably the weight ratio of siloxane polymer / organic polymer is 10/90 to 9/90.
0/10, more preferably 20/80 to 80/20. Within this range, the strength of the film of the image receiving layer and the water resistance to fountain solution during printing will be good.

The binder resin containing the composite of the present invention is characterized in that the hydroxyl group present in the siloxane polymer, for example, the hydroxyl group of the siloxane polymer formed by the hydrolytic polycondensation of the silane compound, and the “ The `` specific bonding group '' forms a uniform organic-inorganic hybrid by hydrogen bonding, becomes microscopically homogeneous without phase separation, and maintains the affinity between the siloxane polymer and the organic polymer used in the present invention. It is estimated that Further, when a hydrocarbon group is present in the siloxane polymer, it is presumed that the affinity with the organic polymer is further improved due to the hydrocarbon group. The composite of the present invention has excellent film-forming properties.

Such an organic-inorganic polymer composite resin is produced by hydrolytic polycondensation of the silane compound and mixing with the organic polymer, or hydrolyzing the silane compound in the presence of the organic polymer. It is easily produced by polycondensation.

Preferably, an organic-inorganic polymer composite can be obtained by hydrolytic polycondensation of the silane compound by a sol-gel method in the presence of an organic polymer. In the formed organic-inorganic polymer composite, the organic polymer is uniformly dispersed in a matrix of a gel (ie, a three-dimensional fine network structure of an inorganic metal oxide) formed by hydrolytic polycondensation of a silane compound.

The sol-gel method as a preferred method can be carried out using a conventionally known sol-gel method. Specifically, "Thin-film coating technology by sol-gel method" (Technical Information Association) (published) (1995), Saio Sakuhana "Science of sol-gel method" (Agne Shofusha) (published) (1988), Takashi Hirashima, "Technology for preparing functional thin films by the latest sol-gel method," General Technology Center (published) (19)
1992) according to a method described in detail in a written document.

The coating solution for the image receiving layer is preferably an aqueous solvent, and furthermore, a water-soluble solvent is used in combination for the purpose of uniform liquefaction by suppressing precipitation during preparation of the coating solution. Examples of the water-soluble solvent include alcohols (methanol, ethanol, propyl alcohol, ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, ethylene glycol monomethyl ether, propylene glycol monomethyl ether, ethylene glycol monoethyl ether, etc.) and ethers (tetrahydrofuran , Ethylene glycol dimethyl ether, propylene glycol dimethyl ether, tetrahydropyran, etc.), ketones (acetone, methyl ethyl ketone, acetylacetone, etc.), esters (methyl acetate, ethylene glycol monomethyl monoacetate, etc.), amides (formamide, N-methylformamide, Pyrrolidone, N-methylpyrrolidone, etc.) It may be used in combination with the above.

Further, in order to promote the hydrolysis and polycondensation reaction of the silane compound represented by the general formula (II),
It is preferable to use an acidic catalyst or a basic catalyst together. 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, the rate of hydrolysis and polycondensation tends to increase. However, when a highly concentrated basic catalyst is used, a precipitate may be formed in the sol solution. Therefore, the concentration of the basic catalyst is preferably 1 N (concentration conversion in an aqueous solution) or less.

The kind of the acidic catalyst or the basic catalyst is not particularly limited. However, when it is necessary to use a catalyst having a high concentration, a catalyst composed of an element that hardly remains in the catalyst crystal grains after sintering is used. Good. Specifically, examples of the acidic catalyst include hydrogen halides such as hydrochloric acid, nitric acid, sulfuric acid,
Sulfurous acid, hydrogen sulfide, perchloric acid, hydrogen peroxide, carbonic acid, carboxylic acids such as formic acid and acetic acid, substituted carboxylic acids obtained by substituting R of the structural formula RCOOH with other elements or substituents, sulfonic acids such as benzenesulfonic acid, Examples of the basic catalyst include ammoniacal bases such as aqueous ammonia, and amines such as ethylamine and aniline.

The image receiving layer of the present invention may contain other components in addition to the components described above. As other components, inorganic pigment particles other than the specific metal hydroxide compound particles of the present invention may be contained. For example, silica, alumina,
Kaolin, clay, zinc oxide, titanium oxide, calcium carbonate, barium carbonate, calcium sulfate, barium sulfate,
Magnesium carbonate and the like. These other inorganic pigments are used in an amount not exceeding 40 parts by weight based on 100 parts by weight of the metal hydroxide compound particles of the present invention. Preferably 2
It is within 0 parts by weight.

The ratio of the pigment (the metal hydroxide compound particles of the present invention and other inorganic pigment particles used as required) / binder resin in the image receiving layer is generally such that the binder resin is based on 100 parts by weight of the pigment. The proportion is 8 to 50 parts by weight, preferably 10 to 30 parts by weight. Within this range, the effects of the present invention are effectively exhibited, the film strength during printing is maintained, and the high hydrophilicity of the non-image area is maintained. In addition, the image portion adheres sufficiently to the image receiving layer,
Even when the number of printed sheets increases, sufficient printing durability can be obtained without causing image loss.

In addition, a crosslinking agent may be added to the image receiving layer in order to further improve the film strength. Examples of the crosslinking agent include compounds that are usually used as a crosslinking agent. Specifically, Shinzo Yamashita and Tosuke Kaneko, “Crosslinking Agent Handbook” Taiseisha (1981), edited by The Society of Polymer Science, “Polymer Data Handbook, Basic Edition” Baifukan (198)
6 years) can be used.

For example, ammonium chloride, metal ions,
Organic peroxides, polyisocyanate compounds (for example, toluylene diisocyanate, diphenylmethane diisocyanate, triphenylmethane triisocyanate, polymethylenephenyl isocyanate, hexamethylene diisocyanate, isophorone diisocyanate, polymer polyisocyanate And polyol compounds (eg, 1,4-butanediol, polyoxypropylene glycol, polyoxyethylene glycol, 1,1,1
-Trimethylolpropane, etc.), polyamine-based compounds (e.g., ethylenediamine, γ-hydroxypropylated ethylenediamine, phenylenediamine, hexamethylenediamine, N-aminoethylpiperazine, modified aliphatic polyamines, etc.), polyepoxy group-containing compounds and epoxy Resins (eg, "New Epoxy Resin" edited by Hiroshi Kakiuchi, Shokodo (1985), "Epoxy Resin" edited by Kuniyuki Hashimoto
Compounds described in Nikkan Kogyo Shimbun (1969) and the like, melamine resins (for example, compounds described in "Uria Melamine Resin" edited by Ichiro Miwa and Hideo Matsunaga, Nikkan Kogyo Shimbun (1969)) Poly (meth) acrylate compounds (for example, Shin Ogawara, Takeo Saegusa, Toshinobu Higashimura, "Oligomer" Kodanmori (1976), Eizo Omori "Functional acrylic resin" Techno System (1985)
And the like)).

The image-receiving layer of the present invention is formed by applying the above-mentioned coating solution on a water-resistant support by using any of the conventionally known coating methods, followed by drying. The thickness of the formed image receiving layer is preferably from 0.2 to 10 μm, more preferably from 0.5 to 8 μm. In this range, a film having a uniform thickness is formed, and the film has sufficient strength.

The image receiving layer of the present invention preferably has a surface smoothness of 30 (sec / 10 cc) or more in Beck smoothness. Further, when plate making is performed by an electrophotographic printer, the preferred range of the toner used is a dry toner or a liquid toner as follows.

In an electrophotographic printer using a dry toner, the surface of the image receiving layer of the original plate of the present invention has a thickness of 30 to 200.
(Second / 10 cc), more preferably 50 to 15
0 (second / 10 cc). Within this range, in the process of transferring the toner image to the master and fixing it, the scattering toner is prevented from adhering to the non-image area (that is, background contamination), and the toner adhesion of the image area is uniform and sufficient, and the fine line
The reproducibility of fine characters and the uniformity of solid image portions are improved.

On the other hand, in an electrophotographic printer using a liquid toner, the surface of the image receiving layer should be 30 (sec / 10 cc) or more, and the higher the better, the better, 150 to 3000 (sec / 10 cc), more preferably 200 to 2500 (sec / cc). 10cc).
In the case of an ink jet printer or a thermal transfer printer, the same range as in the case of the electrophotographic printer using the liquid toner is preferable. Within this range, a high-definition toner image portion such as a fine line, a thin character, or a halftone image is faithfully transferred and formed on the image receiving layer, and the surface of the image receiving layer and the toner image portion are sufficiently adhered to each other. Can be held.

Here, the Beck smoothness can be measured by a Beck smoothness tester, and a test piece is placed on a highly smooth finished circular glass plate having a hole in the center at a constant pressure (1 kg / cm). ² ) Press in a certain amount under reduced pressure (10cc)
The time required for the air to pass between the glass surface and the test piece is measured.

More preferably, the shape of the surface of the image receiving layer of the present invention is set to a state in which the unevenness is high and the interval is close.
Specifically, the surface center average roughness SRa defined by ISO-468 is in the range of 1.3 to 3.5 μm, and the average wavelength Sλa indicating the surface roughness density is in the range of 50 μm or less. preferable. More preferably, SRa is 1.
35 to 2.5 μm, and Sλa is within a range of 45 μm or less. It is presumed that this suppresses the adhesion of the scattered toner to the non-image portion after the electrophotographic plate making and the fatness at the time of fixing the adhered toner.

Next, the water-resistant support provided in the present invention will be described. As the water-resistant support, an aluminum plate, a zinc plate, a copper-aluminum plate, a copper-stainless plate,
Trimetal plates such as bimetal plates such as chrome-copper plates, chromium-copper-aluminum plates, chromium-lead-iron plates, chromium-copper-stainless steel plates, and the thickness is 0.1 to 3 mm, particularly 0.1 to 1 mm. One. In addition, thickness 80μ
Paper, plastic film or metal film-laminated paper or plastic film which has been subjected to a water resistance treatment of m to 200 μm, and the like can be given.

The support used in the present invention preferably has a highly smooth surface. That is, the smoothness of the surface on the side adjacent to the image receiving layer is 300 (sec / 10
cc) or more, more preferably 900 to 3000 (sec / 10
cc), more preferably 1000 to 3000 (sec / 10 cc). By regulating the smoothness of the surface of the support on the side adjacent to the image receiving layer to a Beck smoothness of 300 (sec / 10 cc) or more, image reproducibility and printing durability can be further improved. Such an improvement effect can be obtained even if the smoothness of the image receiving layer surface is the same, and the adhesion between the image portion and the image receiving layer is improved by increasing the smoothness of the support surface. Conceivable.

The highly smooth surface of the water-resistant support thus regulated refers to the surface on which the image receiving layer is directly applied. For example, a conductive layer, an under layer, and an over layer described below are formed on the support. When providing a coat layer, the conductive layer,
Refers to the surface of the underlayer or overcoat layer. As a result, the image receiving layer in which the surface shape is adjusted as described above is sufficiently retained without being affected by the unevenness of the surface of the support, and the image quality can be further improved.

As a method for setting the smoothness within the range, various conventionally known methods can be used. Specifically, a method of adjusting the Beck smoothness of the surface of the support by a method such as a method of melting and bonding the substrate surface with a resin, a method of strengthening a calendar with a highly smooth heat roller, and the like can be used.

The original plate for direct drawing type lithographic printing of the present invention forms a toner image on an image receiving layer provided on a water-resistant support by an electrophotographic recording method, or discharges an oil-based ink using an electrostatic field. It can also be preferably used as a lithographic printing original plate used for forming an image by an electrostatic discharge type inkjet method, and a lithographic printing plate obtained by image formation can print a large number of clear images. It is.

The image formation by the electrophotographic recording system is usually performed by an electrophotographic process, and the transfer of the toner image onto the transfer material is performed by electrostatic transfer. The water-resistant support as a printing original plate is preferably conductive, and particularly preferably has a volume resistivity of 10 ⁴ to 10 ¹³ Ω · cm, more preferably 10 ⁷ to 10 ¹² Ω · cm. As a result, bleeding / distortion of the transferred image, toner adhesion to the non-image portion, and the like are suppressed to such an extent that there is no practical problem, and a good image can be obtained.

Also in the image formation by the electrostatic discharge type ink jet recording system, the water-resistant support is preferably one having conductivity, and at least the portion immediately below the image receiving layer is 10 ¹⁰ Ω · cm. It is preferable that the material has the following specific electric resistance value, and it is more preferable that the entire water-resistant support has a resistivity of 10 ¹⁰ Ω · cm or less. The above-mentioned specific electric resistance value is more preferably 10 ⁸ Ω · cm or less, and the value may be infinitely zero. When the conductivity is within the above range, when the charged ink droplet adheres to the image receiving layer, the charge of the ink droplet quickly disappears through the ground plane, so that a clear image without disturbance is formed. . The measurement of the specific electric resistance (also called the specific electric resistance of the volume or the specific electric resistance) is performed according to JIS.
The test was performed by a three-terminal method provided with a guard electrode based on K-6911.

In order to impart the above-described conductivity to the portion of the support immediately below the image receiving layer, a layer comprising a conductive filler such as carbon black and a binder is provided on a substrate such as paper or film. Examples of the method include coating, attaching a metal foil, and depositing a metal.

On the other hand, examples of the support having conductivity as a whole include conductive paper impregnated with sodium chloride or the like, plastic films mixed with a conductive filler such as carbon black, and metal plates such as aluminum. No.

The conductive water-resistant support which can be preferably used in the present invention will be described in detail. A substrate having conductivity as a whole can be obtained, for example, by using a conductive base paper impregnated with sodium chloride or the like on a substrate and providing a water-resistant conductive layer on both surfaces thereof. As the base paper used as the base, for example, wood pulp paper, synthetic pulp paper, or a mixed paper of wood pulp paper and synthetic pulp paper can be used as it is. Further, the thickness of the base paper is preferably from 80 μm to 200 μm.

The formation of the conductive layer is achieved by applying a layer containing a conductive filler and a binder to both sides of the conductive paper. The thickness of the applied conductive layer is 5 μm to 2 μm.
0 μm is preferred. As the conductive filler, particulate carbon black, graphite, for example, metal powder such as silver, copper, nickel, brass, aluminum, steel, stainless steel, tin oxide powder, flaked aluminum or nickel, fibrous carbon, etc. No.

As the resin used as the binder, various resins are appropriately selected and used. Specifically, as the hydrophobic resin, for example, an acrylic resin, a vinyl chloride resin, a styrene resin, a styrene-butadiene resin,
Styrene-acrylic resin, urethane-based resin, vinylidene chloride-based resin, vinyl acetate-based resin, and the like.Examples of hydrophilic resin include polyvinyl alcohol-based resin, cellulose-based derivative, starch and its derivatives, polyacrylamide-based resin, and styrene. Maleic anhydride copolymers and the like can be mentioned.

Another method for forming the conductive layer is to laminate a conductive thin film. As the conductive thin film, for example, a metal foil, a conductive plastic film, or the like can be used. More specifically, an aluminum foil is used as a metal foil laminate, and a polyethylene resin mixed with carbon black is used as a laminate of a conductive plastic film. The aluminum foil may be either hard or soft and has a thickness of 5μ.
m to 20 μm are preferred.

Extrusion lamination is preferred for laminating polyethylene resin mixed with carbon black. Extrusion lamination method is to heat-melt polyolefin, turn it into a film, and immediately press-bond it to base paper.
This is a method of cooling and laminating, and various devices are known. The thickness of the laminate layer is 10 μm to 30 μm
Is preferred. As the whole support has conductivity,
When a conductive plastic film or metal plate is used as the substrate, it can be used as it is as long as it has sufficient water resistance.

As the plastic film having conductivity, for example, a polypropylene or polyester film mixed with a conductive filler such as carbon fiber or carbon black can be used. As the metal plate, aluminum or the like can be used. The thickness of the substrate is preferably 80 μm to 200 μm. If it is less than 80 μm, the strength as a printing plate is insufficient,
If it exceeds 200 μm, handling properties such as transportability in the drawing apparatus will be reduced.

Next, a structure in which a layer having conductivity is provided will be described. 80 μm to 2 μm thick as a water resistant substrate
Paper having a water resistance of 00 μm, plastic film or paper laminated with metal foil, plastic film, or the like can be used. As a method for forming a conductive layer on a substrate, the method described above in the case where the entire support has conductivity can be used. That is, a layer containing a conductive filler and a binder is formed on one surface of the substrate with a thickness of 5 μm.
Apply at m-20 μm. Alternatively, it can be obtained by laminating a metal foil or a plastic film having conductivity.

As a method other than the above, for example, a metal film such as aluminum, tin, palladium, or gold may be provided on a plastic film. As described above, a water-resistant support having conductivity can be obtained.

In the present invention, a back coat layer (back layer) can be provided on the surface of the support opposite to the image receiving layer for the purpose of preventing curling as described above. The back coat layer has a smoothness. It is preferably in the range of 150 to 700 (sec / 10 cc). Accordingly, when the printing plate is supplied to the offset printing press, the printing plate is accurately set on the printing press without causing displacement or slippage.

The thickness of the water-resistant support provided with the under layer or the back coat layer is in the range of 90 to 130 μm, preferably 100 to 120 μm.

An image is formed on the lithographic printing original plate of the present invention by a thermal transfer recording system, an electrophotographic recording system, an ink jet recording system or the like, and plate making is performed.

As the electrophotographic recording method, any of conventionally known recording methods can be used. For example, Electrophotography Society of Japan, "Basics and Application of Electrophotography Technology" (Corona Co., Ltd., 1988), Kenichi Eda, Journal of Electrophotography Society 27 ,
113 (1988); Kawamoto Akio; 33 , 149 (19)
94), Akira Kawamoto, 32 , 196 (1993), or a commercially available PPC copying machine.
A combination of a scanning exposure method using a laser beam for exposing based on digital information and a developing method using a liquid developer is an effective process because a high-definition image can be formed. An example is shown below.

First, the photosensitive material is positioned on the flat bed by the register pin method, and then suction-fixed from the back surface by air suction and fixed. Next, the photosensitive material is charged by the charging device described in, for example, the above-mentioned “Basics and Application of Electrophotographic Technology”, page 212 and thereafter. The corotron or scotron system is common. At this time, it is also preferable to control the charging conditions by applying feedback so that the surface potential always falls within a predetermined range based on the information from the charged potential detecting means of the photosensitive material. Thereafter, for example, scanning exposure using a laser light source is performed using the method described on page 254 and thereafter of the above-cited reference material.

Next, a toner image is formed using a liquid developer. The photosensitive material charged and exposed on the flatbed can be removed therefrom, and the wet developing method described on page 275 et seq. The exposure mode at this time is performed in correspondence with the toner image development mode. For example, in the case of reversal development, the negative image, that is, the same charge polarity as that when the photosensitive material is charged by irradiating the image portion with laser light and charging the photosensitive material Is applied, and a developing bias voltage is applied so that the toner is electrodeposited on the exposed portion. Details of the principle are described on page 157 et seq.

After development, squeezing such as a rubber roller, a gap roller, and a reverse roller, corona squeezing, and air squeezing are performed in order to remove excess developer. It is also preferable to rinse only the carrier liquid of the developer before squeezing. Next, the toner image formed on the photoreceptor as described above is transferred and fixed on a lithographic printing original plate as a transfer material, or transferred and fixed on a lithographic printing original plate via an intermediate transfer member. Things.

The ink-jet recording method may be any of the conventionally known recording methods, and includes a method for drying an ink image.
An oil-based ink is preferable from the viewpoint of fixability, difficulty of clogging of the ink, and the like, and an electrostatic discharge type ink jet system which does not easily cause image bleeding is preferable. A solid jet system using hot melt ink is also preferably used.

For electrostatic discharge type ink jet recording, a recording apparatus described in International Patent Publication Nos. WO93 / 11866, 97/27058, and 97/27060 is used.
The oil-based ink used is preferably a non-aqueous solvent having an electric resistance of 10 ⁹ Ω · cm or more and a dielectric constant of 3.5 or less, in which solid and hydrophobic resin particles are dispersed at least at room temperature (15 ° C. to 35 ° C.). It is a thing. By using such a dispersion medium, the electric resistance of the oil-based ink is properly controlled, and the ink is appropriately ejected by the electric field, thereby improving the image quality. Further, by using the resin particles as described above, the affinity with the image receiving layer is increased, and good image quality is obtained and printing durability is improved. Specifically, Japanese Patent Application Laid-Open No. 10-2
No. 59336, No. 10-316920, No. 10-20
No. 4354, No. 10-204356, No. 10-315
No. 617 and No. 11-43638.

The solid jet method includes So
lid Inkjet Platemaker SJ02A (Hitachi Koki Co., Ltd.),
Commercially available printing systems such as MP-1200Pro (manufactured by Dynic Corporation) can be used.

The plate making method using the ink jet recording method will be described more specifically with reference to the drawings. The apparatus system shown in FIG. 1 has an ink jet recording apparatus 1 using oil-based ink.

As shown in FIG. 1, first, pattern information of an image (graphics or text) to be formed on the master (lithographic printing original) 2 is transmitted from an information source such as a computer 3 via a bus 4. Through the means, the ink is supplied to the ink jet recording apparatus 1 using oil-based ink. The ink jet recording head 10 of the recording apparatus 1 stores oil-based ink therein, and when the master 2 passes through the recording apparatus 1, ejects minute droplets of the ink to the master 2 according to the information. Thereby, ink adheres to the master 2 in the pattern. In this way, an image is formed on the master 2 to obtain a plate making master (plate making printing original plate).

FIGS. 2 and 3 show examples of the ink jet recording apparatus used in the apparatus system shown in FIG. 2 and 3
In FIG. 1, members common to those in FIG. 1 are denoted by common reference numerals. FIG. 2 is a schematic configuration diagram showing a main part of such an ink jet recording apparatus, and FIG. 3 is a partial sectional view of a head.

As shown in FIGS. 2 and 3, the head 10 provided in the ink jet recording apparatus has a slit sandwiched between the upper unit 101 and the lower unit 102. Has become
The ejection electrode 10b is arranged in the slit, and the oil ink 11 is filled in the slit.

In the head 10, a voltage is applied to the ejection electrode 10b in accordance with a digital signal of pattern information of an image. As shown in FIG. 2, a counter electrode 10c is provided so as to face the discharge electrode 10b.
A master 2 is provided above. By applying a voltage, a circuit is formed between the discharge electrode 10b and the counter electrode 10c, and the oil-based ink 11 is discharged from the discharge slit 10a of the head 10, and an image is formed on the master 2 provided on the counter electrode 10c. It is formed.

It is preferable that the width of the discharge electrode 10b is as narrow as possible in order to form a high quality image. For example, the head 10 of FIG. 3 is filled with oil-based ink, and the ejection electrode 10 b having a tip of 20 μm width is used.
b and the counter electrode 10c are set to 1.5 mm, and a voltage of 3 KV is applied between the electrodes for 0.1 millisecond to obtain 40 μm.
An m dot print can be formed on the master 2.

FIGS. 4 and 5 show examples of the construction of another ink jet recording apparatus. FIG. 4 is a schematic diagram showing only a part of the head for explanation. As shown in FIG. 4, the ink jet recording head 13 includes a head body 14 made of an insulating material such as plastic, ceramic, and glass, and meniscus regulating plates 15 and 16. In the figure, 1
Reference numeral 7 denotes an ejection electrode for applying a voltage to form an electrostatic field in the ejection section.

Further, the head main body will be described in detail with reference to FIG. 5 in which the regulating plates 15 and 16 have been removed from the head. The head main body 14 is provided with a plurality of ink grooves 18 for circulating ink perpendicular to the edge of the head main body. The shape of the ink groove 18 may be set to a range in which capillary force acts so that a uniform ink flow can be formed, and particularly preferably, the width is 10 to 200 μm and the depth is 10 to 30 μm.
0 μm. An ejection electrode 17 is provided inside the ink groove 18. The ejection electrode 17 is formed on the head body 14 made of an insulating material by a known method using a conductive material such as aluminum, nickel, chromium, gold, and platinum. Alternatively, it may be formed only on a part. The discharge electrodes are electrically independent.

The two adjacent ink grooves form one cell, and the leading end of the partition wall 19 at the center of the cell forms the ejection portion 2.
0 and 20 'are provided. In the discharge portions 20 and 20 ′, the partition walls are thinner than the other partition portions 19 and are sharpened. The tip of the discharge section may be slightly chamfered as in 20 '. Such a head body is manufactured by a known method such as machining, etching, or molding of an insulating material block. The thickness of the partition wall at the discharge portion is preferably 5 to 100 μm, and the radius of curvature of the sharpened tip is preferably 5 to 50 μm. Although only two cells are shown in the figure, the cells are separated by a partition 21 and the tip 22 thereof is connected to the discharge unit 2.
It is chamfered so as to be retracted from 0, 20 '.

The ink is supplied to this head from the direction I by ink supply means (not shown) through the ink groove, and the ink is supplied to the discharge section. Excess ink is collected in the O direction by an ink collecting means (not shown).
As a result, fresh ink is always supplied to the ejection unit. In a state in which the ink near the ejection unit is irradiated with light as shown in L, the ink is provided on the ejection electrode with respect to a counter electrode (not shown) which is provided so as to face the ejection unit and holds a lithographic printing original plate on its surface. By applying a signal voltage corresponding to the data, the ink is ejected from the ejection unit and an image is formed on the lithographic printing original plate.

As described above, on the lithographic printing original plate,
An image is formed by an ink-jet method using an oil-based ink to obtain a plate-making master.

[0108]

EXAMPLES Hereinafter, the present invention will be described in more detail by way of examples, but the present invention is not limited to these examples.

Example 1 and Comparative Example A Titanium hydroxide [Ti (OH) ₄ , average particle size 0.3 μm] 1
In a paint shaker (manufactured by Toyo Seiki Co., Ltd.), 100 g, 113 g of a 10 wt% aqueous solution of polyvinyl alcohol PVA117 (manufactured by Kuraray Co., Ltd.) and 240 g of water were dispersed together with glass beads for 30 minutes. Further, 110 g of a 20 wt% (water / ethanol (1/1) weight ratio) solution of tetraethoxysilane hydrolyzed in advance and 200 g of colloidal silica (Snowtec C (20 wt% aqueous dispersion, manufactured by Nissan Chemical Industries, Ltd.)) Was added and dispersed for 3 minutes, and then the glass beads were separated by filtration to obtain a dispersion.

Support for ELP-2X type master (manufactured by Fuji Photo Film Co., Ltd.) used as electrophotographic lithographic printing original plate for light seal [Beck smoothness of under side: 20
00 (second / 10 cc)], using a wire bar to apply the above-described image receiving layer composition so that the coating amount after drying becomes 8 g / m ² , and drying in an oven at 100 ° C. for 10 minutes. An image receiving layer was prepared and used as a lithographic printing original plate.

<Comparative Example A> A lithographic printing plate precursor was prepared in the same manner as in Example 1 except that titanium oxide (TiO ₂ : average particle diameter: 0.3 μm) was used instead of titanium hydroxide. It was created.

The performance results of the respective plates obtained as described above are shown in Table-A.

[0113]

[Table 1]

The evaluation items described in Table-A were performed according to the following contents.

Note 1) Smoothness A lithographic printing plate was converted to a Beck smoothness tester (Kumaya Riko Co., Ltd.)
And its smoothness (second / 1
0 cc).

Note 2) Contact angle with water 2 μl of distilled water was placed on the surface of the lithographic printing plate precursor, and the surface contact angle (degree) after 30 seconds at room temperature was measured using a surface contact angle meter (C).
AD, manufactured by Kyowa Interface Science Co., Ltd.).

Note 3) Image reproducibility Using the lithographic printing plate prepared as described above, a Servo Proter DA8400 manufactured by Graphtec Co., Ltd., capable of drawing the output of a personal computer, was modified and shown in FIG. 4 in the Ben plotter section. The ink discharge head was mounted, and printing was performed on the lithographic printing original plate placed on the counter electrode spaced at a distance of 500 μm using the oil-based ink (IK-1) described below to make a plate. Next, RICOH FUSER model 592
Using Ricoh Co., Ltd., the surface temperature of the ink image surface was adjusted to 80 ° C. and heated for 1 minute to sufficiently fix the image area. A copy image of the obtained plate (ie, printing plate) was visually observed at a magnification of 200 times with an optical microscope.

<Preparation of oil-based ink (IK-1)> 12 g of dispersion stabilizing resin (PS-1) having the following structure, vinyl acetate 1
A mixed solution of 00 g and Isopar G 321 g was heated to a temperature of 75 ° C. while stirring under a nitrogen stream. 1.5 g of 2,2'-azobis (isovaleronitrile) (abbreviated AIVN) was added as a polymerization initiator, and the mixture was reacted for 3 hours. Furthermore, after adding 1.0 g of this initiator and reacting for 3 hours, the temperature was raised to 100 ° C. and the mixture was stirred for 2 hours, and unreacted vinyl acetate was distilled off. After cooling, the mixture was passed through a 200-mesh nylon cloth, and the resulting white dispersion was 93% polymerized and had an average particle size of 0.1%.
It was a 38 μm latex having good monodispersibility. The particle size was measured with CAPA-500 (manufactured by Horiba, Ltd.).

[0119]

Embedded image

A part of the white dispersion was centrifuged (rotation speed: 1 × 10 ⁴ rpm, rotation time: 60 minutes), and the sedimented resin particles were collected and dried. The weight average molecular weight (Mw; GPC value in terms of polystyrene) of the resin particles is 2
× 10 ⁵ , the glass transition point (Tg) was 38 ° C. (referred to as resin particles (PL-1)).

On the other hand, 10 g of a dodecyl methacrylate / acrylic acid copolymer (copolymerization ratio: 95/5 weight ratio), 10 g of nigrosine and 30 g of Isopar G were put together with glass beads in a paint shaker (manufactured by Toyo Seiki Co., Ltd.) for 4 hours. It was dispersed to obtain a fine dispersion of nigrosine.
20 g of the above resin particles (PL-1) (as a solid content),
A black oil-based ink (IK-1) was prepared by diluting 7.5 g of the above nigrosine dispersion and 0.06 g of the dodecene-half-maleic acid octadecylamide copolymer into 1 liter of Isopar E.

Note 4) Printing durability An image was formed and fixed on a lithographic printing plate in the same manner as in Note 3) to produce a lithographic printing plate. Using this printing plate, a solution prepared by diluting a treating agent for PS plate: EU-3 (manufactured by Fuji Photo Film Co., Ltd.) 50 times with water as immersion water, and using Oliver 94 type (manufactured by (Manufactured by Sakurai Seisakusho) using black ink for offset printing. The number of printed sheets having a clear image free of background stains and free of fine lines, characters and the like is represented as printing durability.

From the results in Table A, it can be seen from Example 1 and Comparative Example A
The surface smoothness of the image receiving layer was almost the same, the contact angle with water was 0 degree, and the hydrophilicity of the surface was good. In Example 1, the actually made plate had no bleeding or distortion in the thin lines and fine characters, the solid portion had sufficient density, and the dot image on the plate was good in a perfect circular shape. On the other hand, in Comparative Example A, the dot shape, fine lines, fine characters, and the like were the same as in Example 1, but the density of the solid portion was low.
When the obtained plate was actually printed, in Example 1, 10,000 prints of a clear image without printing ink adhesion stains were obtained in the non-image portion, whereas in Comparative Example A, the non-image portion was printed. No stain was generated, but a missing image portion occurred on about 1500 sheets.

Examples 2 to 11 Instead of 100 g of titanium hydroxide in Example 1, each of the compounds shown in Table B below (the average particle size of each particle was 0.0
Each lithographic printing original plate was prepared in the same manner as in Example 1 except that 100 g of (3-2 μm) was used. The Beck smoothness of the surface of each of the obtained masters is 250 to 300 (sec / 10 cc).
The contact angle with water was 0 degree. In the same manner as in Example 1, each of the plate-making products produced in the same manner as in Example 1 had good image quality in which fine lines, fine characters were not missing, blurred, and distorted. Table B shows the printing durability in printing. Each plate exhibited printing durability of 3,000 or more.

[0125]

[Table 2]

Example 12 <Preparation of a lithographic printing plate precursor for direct drawing> The following contents were added together with glass beads to a paint shaker (Toyo Seiki Co., Ltd.)
) For 30 minutes at room temperature, and the glass beads were separated by filtration to obtain a dispersion.

Nickel hydroxide (manufactured by Nakarai Co., Ltd., average particle size: 40 nm) 42.5 g 10 wt% aqueous solution of gelatin 100 g Colloidal silica 20 wt% dispersion (Snowtec C) 37 g Tetraethoxysilane 15 g Fluoroalkyl ester FC- 430 (manufactured by 3M) 0.2 g Curing agent CH ₂ = CHSO ₂ CH ₂ CONH (CH ₂ ) ₃ NHCOCH ₂ SO ₂ CH = CH ₂ 0.5 g 1N hydrochloric acid 2 g Water / ethanol (1/1) weight ratio mixed solvent 200g

Using a support of ELP-2X type master,
The above composition was applied thereon using a wire bar so as to have a coating amount after drying of 6 g / m ² , dried by touch, and further heated at 110 ° C. for 30 minutes to form an image receiving layer. The original plate was used for printing. The Beck smoothness of the surface of the obtained master plate was 800 (sec / 10 cc), and the contact angle with water was 5 degrees or less.

<Electrophotographic photoreceptor> 2 g of X-type metal-free phthalocyanine (manufactured by Dainippon Ink and Chemicals, Inc.) and the following binder resin (P
-1) 14.4 g, the following binder resin (P-2) 3.6 g,
0.15 g of the following compound (A) and cyclohexanone 80
g of the mixture was placed in a 500 ml glass container together with glass beads, and dispersed in a paint shaker (manufactured by Toyo Seiki Seisaku-sho) for 60 minutes. The glass beads were filtered off to obtain a photosensitive layer dispersion. Next, this dispersion was subjected to a degreasing treatment.
Apply it on a 2mm thick amilnium plate with a wire bar,
After drying to the touch, it was heated in a circulation oven at 110 ° C. for 20 seconds. The thickness of the obtained photosensitive layer was 8 μm.

[0130]

Embedded image

The electrophotographic photoreceptor prepared as described above is corona-charged in a dark place to charge the surface potential to +450 V, then read in advance from a document by a color scanner, color-separated, and subjected to some system-specific. After applying the correction relating to the color reproduction of the image, based on the information stored in the hard disk in the system as digital image data, the beam spot diameter was changed to 788 nm using a semiconductor laser drawing apparatus as an exposure apparatus. Exposure was performed at a pitch of 10 μm and a scan speed of 300 cm / sec as 15 μm (that is, 2500 dpi). Exposure was performed so that the exposure amount on the photoconductor at this time was 25 erg / cm ² .

Subsequently, development was carried out using a liquid developer having the following contents, followed by rinsing in a single bath of Isopar G to remove stains on the non-image area, and then using hot air at which the surface temperature of the photosensitive member became 50 ° C. The remaining amount of Isopar G is (10mg / toner weight g)
And dried. Subsequently, the photosensitive member was precharged at −6 KV with a corona charger, the image surface of the photosensitive member was overlapped with the lithographic printing plate precursor, and transferred by applying a negative corona discharge from the electrophotographic photosensitive member side. .

<Liquid developer> The following components were mixed in a kneader and kneaded at 95 ° C for 2 hours to obtain a mixture. The mixture was cooled in a kneader and then ground in the same kneader. One part by weight of the ground product and 4 parts by weight of Isopar H were dispersed with a paint shaker for 6 hours to obtain a dispersion. This dispersion is diluted with Isopar G so that the toner solid content is 1 g per liter, and at the same time, basic barium petrone is used as a charge control agent for imparting negative charge.
A liquid developer was prepared so as to contain 0.1 g per liter.

(Kneading Composition) Ethylene / methacrylic acid copolymer 4 parts by weight (manufactured by DuPont Mitsui, Nucrel N-699) Carbon black # 30 (manufactured by Mitsubishi Kasei Corporation) 1 part by weight Isopar L (manufactured by Exxon) ) 15 parts by weight

The lithographic printing original plate on which the image was formed was placed at a temperature of 10
By heating at 0 ° C. for 30 seconds, the toner image area was completely fixed. The obtained image of the plate was observed and evaluated at a magnification of 200 times with an optical microscope. The image was clear with no bleeding or missing of fine lines and characters.

Next, the printing plate prepared as described above was used as a printing machine with an Oliver 94 type (manufactured by Sakurai Seisakusho Co., Ltd.), and as a dampening solution, an SLM-OD (Mitsubishi Paper Mills Co., Ltd.).
Was diluted 100 times with distilled water, and the solution was placed in a fountain solution tray, and printing was performed through printing paper using black ink for offset printing. When the printed image of the tenth printed material was visually evaluated using a 20-fold loupe, no background stain due to the adhesion of the printing ink to the non-image portion was observed, and the uniformity of the solid image portion was good. Further, when observed with an optical microscope at a magnification of 200 times, no fine lines or fine characters were found to be thin or missing. Further, 10,000 or more prints having the same print quality were obtained.

Example 13 <Preparation of Water-Resistant Support> The substrate had a basis weight of 100 g / m 2.
^A polyethylene paper was laminated on both sides of a water-resistant base paper having a thickness of 115 μm and having a thickness of 15 μm on one side to prepare a WP paper having the other side of 20 μm. Then, a coating for an under layer having the following composition was applied on a surface having a polyethylene laminate layer of 15 μm using a wire bar, and a dry coating amount of 10 g /
After providing an under layer of m ^2, the under layer has a smoothness of 1
A calendar process was performed so as to be about 500 (second / 10 cc).

<Under Layer Coating> The following components were mixed, and water was added so that the total solid content concentration was 25% to obtain an under layer coating.・ 7.2 parts of carbon black (30% aqueous dispersion) ・ 52.8 parts of clay (50% aqueous dispersion) ・ 36 parts of SBR latex (solid content 50%, Tg 25 ° C.) 36 parts ・ Melamine resin (solid content 80%, Sumiretsu Resin SR-613) 4 parts

The specific electric resistance of the obtained under layer is:
It was measured as follows. The under layer paint is applied on a sufficiently degreased and washed stainless steel plate, and the dry coating amount is 10 g.
/ M ² . The specific electrical resistance of the obtained sample was measured by a three-terminal method provided with a guard electrode based on JIS K-6911, and a value of 1 × 10 ⁸ Ω · cm was obtained.

[Preparation of Direct-Drawing Lithographic Printing Plate] The following composition was dispersed together with glass beads in a paint shaker (Toyo Purification Co., Ltd.) for 20 minutes at room temperature, and the glass beads were separated by filtration. I got

Zinc hydroxide (average particle size: 0.5 μm) 80 g Starch (PENON ZP-2, manufactured by Nisseki Chemical Co., Ltd.) 10% aqueous solution 300 g Clay 10 g Tetraethoxysilane 30 g Methyltrimethoxysilane 3 g Alumina sol-520: Average particle size 10-20 nm 10 g (Nissan Chemical Co., Ltd.) Ethanol 110 g 1N hydrochloric acid 5 g Water 150 g

This dispersion was coated on the above water-resistant support using a wire bar so that the coating amount of a dryer was 6 g / m ² , dried in an oven at 100 ° C. for 20 minutes, and printed. A master plate was prepared. The surface of the obtained master had a Beck smoothness of 150 (sec / 10 cc) and a contact angle with water of 0 °.

The above lithographic printing original plate was converted to an AM-Straight
Laser printer using dry toner commercially available as Imaging System (AMSIS 1200-J Pl
Plate-making was performed through ateSetter (trade name).

When the copy image of the obtained plate-making product was visually evaluated using a 20-fold loupe, the plate-making quality was good. That is, the plate-making product of the present invention obtained by dry toner transfer from a laser printer has no thin lines, no missing fine characters, a uniform solid portion, no uneven toner transfer, and no non-image portion. In addition, the ground fogging due to toner scattering was fine and good without practical problems.

Next, after making a lithographic printing plate precursor by the same operation as described above, using a fully automatic printing machine (AM-2850, manufactured by Am Co., Ltd.) as a dampening solution, a PS plate was prepared. A solution obtained by diluting the treating agent EU-3 (manufactured by Fuji Photo Film Co., Ltd.) 50 times with distilled water is placed in a fountain solution tray, and the plate is printed through a plate using a black ink for offset printing. Done. The printed image (ground fog, solid uniformity of the image area) of the tenth print was visually evaluated using a 20-fold loupe, and was found to be extremely good. In addition, 10,000 good prints were obtained.

Examples 14 to 20 In Example 1, the PVA 117 of the coating solution for the image receiving layer was used.
A lithographic printing plate precursor was prepared in the same manner as in Example 1, except that the following organic polymers and silane compounds in Table-C were used instead of tetraethoxysilane.

[0147]

[Table 3]

The Beck smoothness of the surface of each of the obtained masters was in the range of 250 to 300 (sec / 10 cc), and the degree of contact with water on the surface was 0 °. In the same manner as in Example 1, plate making and printing were performed as a printing plate, and the obtained printed matter was of a clear image quality with no stain on the non-image portion, similarly to the printed matter of Example 1. The printing durability was as good as 10,000 or more.

Example 21 A composition having the following contents was dispersed in a paint shaker for 20 minutes to obtain a dispersion, and the composition was dried on a support for ELP-2X so that the coating amount after drying was 6 g / m ^2. And dried to the touch. Then, it was heated at 100 ° C. for 30 minutes to prepare a lithographic printing plate precursor.

<Image receiving layer composition> Nickel hydroxide (average particle size: 40 nm) 45 g Silica (Sylysia 310, manufactured by Fuji Silysia Chemical Ltd.) 5 g Succinic acid-modified starch (PENON-F3, Niseki Chemical Co., Ltd.) 30 g tetraethoxysilane 28 g benzyltrimethoxysilane 2 g 1N hydrochloric acid 2 g water 300 g

The Beck smoothness of the obtained image receiving layer is 30.
0 (sec / 10 cc), and the contact angle with water on the surface was 5 degrees or less.

Plate making was performed using the electrostatic ink jet recording apparatus described in International Patent Publication No. WO93 / 11866, using the oil ink (IK-1) of Example 1 as the oil ink. The image quality of the obtained plate-making product was clear without distortion and blurring in fine images such as fine lines and fine characters. Next, the obtained printed matter printed in the same manner as in Example 1 has clear image quality with no stain on the non-image area, and has a printing durability of 10,000 sheets or more, similarly to the printed matter of Example 1. There was good.

[0153]

By using the original plate for direct drawing type lithographic printing of the present invention, it is possible to obtain an excellent image in which not only a uniform background stain but also a dot-like background stain is not generated. Further, it is possible to print a large number of prints of a clear image without any loss or distortion of the image.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram showing an example of an apparatus system that can be used for forming an image on a lithographic printing original plate of the present invention.

FIG. 2 is a schematic configuration diagram showing a main part of an ink jet recording apparatus that can be used for forming an image on a lithographic printing plate precursor according to the present invention.

FIG. 3 is a partial cross-sectional view of a head of an ink jet recording apparatus that can be used for forming an image on a lithographic printing original plate of the present invention.

FIG. 4 is a schematic diagram of a main part of a head of another ink jet recording apparatus that can be used for forming an image on a lithographic printing original plate of the present invention.

5 is a schematic diagram for explaining a head body of the ink jet recording apparatus shown in FIG. 4;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Ink-jet recording apparatus 2 Lithographic printing master (master) 3 Computer 4 Bus 10 Head 10a Discharge slit 10b Discharge electrode 10c Counter electrode 11 Oil-based ink 101 Upper unit 102 Lower unit 13 Ink-jet recording head 14 Head body 15, 16 Meniscus regulating plate 17 Discharge electrode 18 Ink groove 19 Partition wall 20, 20 'Discharge section 21 Partition wall 22 Tip

Claims (3)

[Claims] An average particle size of 0.01 to 1 on a water-resistant support.
Composite of 5 μm metal hydroxide compound particles represented by the following general formula (I), a siloxane bond-containing resin in which Si is connected via an oxygen atom, and an organic polymer containing a group capable of forming a hydrogen bond with the resin. A direct-drawing lithographic printing plate precursor having an image receiving layer containing at least a binder resin containing a body. General formula (I) M (OH) _x [In general formula (I), M is Mg, Ba, Al, Ti, Z
represents a metal atom of n, Cu, Ni, Sn, Co, Ge, Fe or La. x represents the valence of the metal M. ] 2. The image receiving layer according to claim 1, wherein the siloxane bond-containing resin is a polymer obtained by hydrolytic polycondensation of at least one silane compound represented by the following general formula (II). An original plate for direct drawing type lithographic printing. General formula (II) (R ⁰ ) _n Si (Y) _4-n [In general formula (II), R ⁰ represents a hydrogen atom, a hydrocarbon group or a heterocyclic group. Y is a hydrogen atom, a halogen atom, -O
R ¹ , —OCOR ² or —N (R ³ ) (R ⁴ ) (R ¹ and R ² each represent a hydrocarbon group; R ³ and R ⁴ may be the same or different; Represents a hydrogen group). n represents 0, 1 or 2. However, the number of Si atoms is 3
Excludes cases where more than one hydrogen atom is bonded. ] 3. The direct drawing type lithographic printing plate precursor according to claim 1, wherein the smoothness of the surface of the image receiving layer is 30 (sec / 10 cc) or more in Beck smoothness.