JP2002268216A - Original plate of planographic printing plate without requiring dampening water - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an original plate of a planographic printing plate without requiring dampening water having such good storage stability as to prevent degeneration and the lowering of sensitivity even after long-term storage and to provide an original plate of a planographic printing plate not requiring dampening water having a high safety recording layer having high sensitivity to laser light for writing and not generating a harmful material in recording. SOLUTION: Each of the original plates is obtained by stacking a photothermal converting layer which converts laser light to heat and a silicone rubber layer in this order on a base and the photothermal converting layer contains a photothermal converting agent and a polyurethane resin having at least one carboxyl group and a polymerizable or crosslinkable functional group.

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 that does not require dampening solution by heat mode recording using a laser beam and that does not require dampening solution. The present invention also relates to a lithographic printing plate precursor having good storage stability and high sensitivity, which does not require a dampening solution. The lithographic printing plate precursor requiring no dampening solution may be hereinafter referred to as a lithographic printing plate precursor without water, as appropriate.

[0002]

2. Description of the Related Art In a conventional printing method using a lithographic printing plate, which requires a dampening solution, it is difficult to control a delicate balance between the dampening solution and the ink. In some cases, ink density defects and background stains occur, causing waste paper. In contrast, waterless lithographic plates have many advantages because they do not require fountain solution. A lithographic printing plate without water for performing lithographic printing without using dampening water is disclosed in, for example, JP-B-44-23042 and JP-B-46-16.
No. 044, JP-B-54-26923, JP-B-56-1
No. 4976, JP-B-56-23150, JP-B-61-
No. 54222, JP-A-58-215411, JP-A-Hei-2
Various types have been proposed in, for example, Japanese Patent Application Laid-Open No. 16561 and Japanese Patent Application Laid-Open No. 2-236550.

On the other hand, in recent years, with the rapid progress of output systems such as a prepress system, an image setter, and a laser printer, a print image is converted into digital data and printed by a new plate making method such as a computer toe plate or a computer toe cylinder. How to get the plate has been proposed. Accordingly, new types of printing materials for these printing systems have been desired and are being developed.

An example in which a waterless lithographic printing plate can be formed by writing using a laser beam is disclosed in Japanese Patent Publication No. Sho 42-2.
1879, JP-A-50-158405, JP-A-6-1985
55723, JP-A-6-186750, US Pat.
No. 53,705 and WO-9401280. These are sequentially provided on a support with a light-to-heat conversion layer containing a light-to-heat conversion agent such as carbon black and a self-oxidizing binder such as nitrocellulose, and an ink-repellent silicone rubber layer. It is described that a part is removed to make the area ink-adhesive and to perform waterless printing. However, in these light-to-heat conversion layers, nitrocellulose and a self-oxidizing nitrogen-containing compound such as ammonium nitrate are used as thermal decomposition compounds, and carbon black in the light-to-heat conversion layer absorbs laser light and generates heat. When the light-to-heat conversion layer is destroyed,
Decomposition of nitrocellulose generates harmful gases such as nitrogen oxides, which is not preferable for environmental health.

In order to solve the environmental problems caused by the thermally decomposable nitrogen-containing compound such as nitrocellulose, Japanese Patent Application No. Hei 11
No. 373622 proposes a laser-writable waterless planographic printing plate precursor containing a polyurethane resin and a photothermal conversion agent in a photothermal conversion layer. However, in this waterless lithographic printing plate precursor, the storage stability of the waterless lithographic printing plate precursor itself fluctuates due to the conditions for synthesizing the polyurethane resin. There was a problem that the silicone rubber layer peeled off.

In order to prevent the silicone rubber layer from peeling off, JP-A-9-146265 and JP-A-11-174666 disclose a method of increasing the adhesive force of the silicone rubber layer by adding a group capable of reacting with a crosslinking agent to the polymer side chain. A technique has been reported in which an addition polymer having a chain is contained, and the polymer is reacted with a crosslinking agent of the silicone rubber layer during coating and drying of the silicone rubber layer to enhance the adhesiveness. But,
With the addition polymer used in the above technique, sufficient sensitivity cannot be achieved, and further, there is a problem that harmful gas containing an ethylenically unsaturated monomer is generated with the decomposition of the polymer, which is not preferable for environmental health.

[0007]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a waterless lithographic printing plate precursor having good storage stability without deterioration or reduction in sensitivity even when stored for a long period of time. Another object of the present invention is to provide a waterless lithographic printing plate precursor having a highly safe recording layer that is highly sensitive to a writing laser and does not generate harmful substances during recording. .

[0008]

Means for Solving the Problems As a result of intensive studies, the present inventors have found that by including a specific polyurethane resin in the light-to-heat conversion layer, storage stability without deterioration and sensitivity deterioration can be maintained even when stored for a long time. It has been found that a waterless planographic printing plate precursor having good properties can be obtained. More specifically,

<1> A lithographic printing plate precursor requiring no dampening solution, in which a photothermal conversion layer for converting laser light into heat and a silicone rubber layer are laminated in this order on a support, wherein the photothermal conversion layer is A lithographic printing plate precursor requiring no dampening solution, comprising: a photothermal conversion agent; and a polyurethane resin having at least one carboxyl group and having a polymerizable or crosslinkable functional group.

<2> The polymerizable or crosslinkable functional group is
<1> is an ethylenically unsaturated bond group
A lithographic printing plate precursor that requires no dampening solution as described.

The lithographic printing plate precursor requiring no dampening solution according to the present invention does not contain a self-oxidizing compound such as nitrocellulose in the light-to-heat conversion layer.
No destruction occurs and no harmful substances such as nitrogen oxides are generated. Therefore, the lithographic printing plate precursor requiring no dampening solution of the present invention has an advantage of having high safety in industry.

The lithographic printing plate precursor requiring no fountain solution of the present invention has a photothermal conversion layer comprising a polyurethane resin into which a polymerizable or crosslinkable functional group, that is, an ethylenically unsaturated bonding group has been introduced. The cross-linking agent or addition reactive functional group contained in the silicone rubber layer and the ethylenically unsaturated bond group contained in the photothermal change layer efficiently form an interaction, increasing the adhesion between the silicone rubber layer and the photothermal conversion layer. And has the advantage of increasing storage stability.

Further, the lithographic printing plate precursor requiring no dampening solution according to the present invention uses a polyurethane resin having a carboxyl group for the light-to-heat conversion layer, so that the decomposition temperature of the light-to-heat conversion layer is kept low, and the silicone rubber is irradiated by laser. The adhesive force between the layer and the light-to-heat conversion layer is efficiently reduced, and as a result, there is an advantage that the layer is highly sensitive to a writing laser.

As described above, the lithographic printing plate precursor requiring no dampening solution of the present invention has good storage stability without deterioration and sensitivity deterioration even when stored for a long period of time, and is excellent in the writing laser. It is considered that the recording layer has high sensitivity and high security and does not generate harmful substances during recording.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a lithographic printing plate precursor requiring no dampening solution (a lithographic printing plate precursor without water) of the present invention will be described in detail.

The lithographic printing plate precursor requiring no dampening solution of the present invention is obtained by sequentially laminating a light-to-heat conversion layer and a silicone rubber layer on a support, and if these two layers are formed in this order, the layer The structure is not particularly limited, and an intermediate layer, an overcoat layer, a backcoat layer, and the like can be provided according to the purpose as long as the effects of the present invention are not impaired.

[Light-to-heat conversion layer] The feature of the waterless lithographic printing plate precursor according to the present invention lies in the light-to-heat conversion layer. That is, the light-to-heat conversion layer comprises a polyurethane resin having at least one carboxyl group and a polymerizable or crosslinkable functional group (hereinafter referred to as (A) a specific polyurethane resin), and (B) a light-to-heat conversion agent as essential components. It may be contained and, if desired, another compound may be used in combination. Here, the “polymerizable or crosslinkable functional group” is a functional group having at least one ethylenically unsaturated double bond, and is thereby used as a crosslinking agent in the silicone rubber layer or in the addition type silicone. Forms an interaction with an addition-reactive functional group. Further, in order to form a good interaction and further strengthen the adhesive force between the silicone rubber layer and the light-to-heat conversion layer, it is necessary to have two or more ethylenically unsaturated double bonds in the molecule. preferable.
First, the light-to-heat conversion layer will be described.

(A) Specific Polyurethane Resin (A) The specific polyurethane resin used in the present invention is:
(A) represented by at least one diisocyanate compound and at least one diol compound represented by the formula (1), (2) or (3) (hereinafter referred to as (ii) a diol compound having a carboxyl group) And / or (c) a structural unit derived from a compound obtained by ring-opening tetracarboxylic dianhydride with (d) a diol compound;
(E-1) a polyurethane resin having, as a basic skeleton, a structural unit that is a reaction product of a structural unit derived from a diol compound having a polymerizable or crosslinkable functional group,

Alternatively, the polyurethane resin is a polyurethane resin obtained by introducing (e-2) a structural unit having a polymerizable or crosslinkable functional group into the polymer terminal of the polyurethane resin consisting of the above (a) to (d). In the present invention, (a) a diol compound having a carboxyl group that reacts with a diisocyanate compound and (c) tetracarboxylic dianhydride are opened with a (d) diol compound. Compounds "are collectively referred to as diol compounds. Hereinafter, each compound constituting the specific polyurethane resin (A) according to the present invention will be described.

(A) Isocyanate compound As the (A) isocyanate compound constituting the specific polyurethane resin (A) according to the present invention, the following are mentioned. A diisocyanate compound represented by the following general formula (4). OCN-L ¹ -NCO (4) In the formula, L ¹ represents a divalent aliphatic or aromatic hydrocarbon group which may have a substituent. If necessary, L ¹ may have another functional group which does not react with the isocyanate group, for example, an ester, urethane, amide or ureido group.

The diisocyanate compound represented by the general formula (4) specifically includes the following compounds. That is, 2,4-tolylene diisocyanate,
2,4-tolylene diisocyanate dimer, 2,6-
Tolylene diisocyanate, p-xylylene diisocyanate, m-xylylene diisocyanate, 4,
Aromatic diisocyanate compounds such as 4'-diphenylmethane diisocyanate, 1,5-naphthylene diisocyanate, 3,3'-dimethylbiphenyl-4,4'-diisocyanate; hexamethylene diisocyanate, trimethylhexamethylene diisocyanate, lysine diisocyanate, dimer Aliphatic diisocyanate compounds such as acid diisocyanate; isophorone diisocyanate, 4,4′-methylenebis (cyclohexyl isocyanate), methylcyclohexane-2,4
(Or 2,6) an alicyclic diisocyanate compound such as diisocyanate, 1,3- (isocyanatomethyl) cyclohexane and the like; a diol such as an adduct of 1 mol of 1,3-butylene glycol and 2 mol of tolylene diisocyanate And a diisocyanate compound which is a reaction product of diisocyanate.

(B) Diol Compound Having Carboxyl Group (B) The (B) diol compound constituting the specific polyurethane resin (A) according to the present invention includes compounds represented by formulas (1), (2)
(3) Structural units represented by at least one of the diol compounds, and / or (c) compounds obtained by ring-opening tetracarboxylic dianhydride with (d) a diol compound.

[0023]

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Where R^TwoIs a hydrogen atom, a substituent (for example,
Cyano, nitro, halogen atom, (-F, -Cl, -B
r, -I), -CONH_Two, -COOR^Three, -OR^Three, −
NHCONHR^Three, -NHCOOR^Three, -NHCOR^Three,
-OCONHR^Three(Where R ^ThreeIs an alkyl having 1 to 10 carbon atoms
And a aralkyl group having 7 to 15 carbon atoms. )Such
Each group of is included. Alkyl) optionally having
Represents aralkyl, aryl, alkoxy, aryloxy groups
And preferably a hydrogen atom, an alkyl having 1 to 8 carbons,
It represents an aryl group having 6 to 15 carbon atoms.

L ⁷ , L ⁸ and L ⁹ may be the same or different and have a single bond and a substituent (for example, alkyl, aralkyl, aryl, alkoxy and halogeno groups are preferred). Represents a divalent aliphatic or aromatic hydrocarbon group which may be an alkylene group having 1 to 20 carbon atoms, an arylene group having 6 to 15 carbon atoms, and more preferably an alkylene group having 1 to 8 carbon atoms. Represents a group. Further, if necessary, L ⁷ , L ⁸ and L ⁹ may have another functional group which does not react with an isocyanate group, for example, a carbonyl, ester, urethane, amide, ureide or ether group. Note that two or three of R ² , L ⁷ , L ⁸ , and L ⁹ may be bonded to each other to form a ring. Ar represents a trivalent aromatic hydrocarbon group which may have a substituent, and preferably represents an aromatic group having 6 to 15 carbon atoms.

Specific examples of the diol compound having a carboxyl group represented by the formula (1), (2) or (3) include the following. That is,
3,5-dihydroxybenzoic acid, 2,2-bis (hydroxymethyl) propionic acid, 2,2-bis (2-hydroxyethyl) propionic acid, 2,2-bis (3-hydroxypropyl) propionic acid, bis ( Hydroxymethyl) acetic acid, bis (4-hydroxyphenyl) acetic acid, 2,
2-bis (hydroxymethyl) butyric acid, 4,4-bis (4
-Hydroxyphenyl) pentanoic acid, tartaric acid, N, N-
Dihydroxyethyl glycine, N, N-bis (2-hydroxyethyl) -3-carboxy-propionamide and the like.

(C) Tetracarboxylic dianhydride The preferred (C) tetracarboxylic dianhydride used in the synthesis of the specific polyurethane resin (A) according to the present invention includes the following formulas (5), (6) and And (7).

[0028]

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In the formula, L ¹⁰ is a single bond, a substituent (eg, alkyl, aralkyl, aryl, alkoxy, halogeno,
Ester and amide groups are preferred. ) May have a divalent aliphatic or aromatic hydrocarbon group, -CO-,-
_{SO -, - SO 2 -,} - O- or S- are shown, preferably a single bond, the number 1-15 divalent aliphatic hydrocarbon group having a _{carbon, -CO -, - SO 2 -} , - O- Or S-.
R ⁴ and R ⁵ may be the same or different and represent a hydrogen atom, an alkyl, an aralkyl, an aryl, an alkoxy, or a halogeno group, preferably a hydrogen atom, an alkyl having 1 to 8 carbons, and a carbon number of 6 ~ 15 aryl, 1 carbon atom
Shows eight alkoxy or halogeno groups. L ¹⁰ , R
Two of R ⁴ and R ⁵ may combine to form a ring.

R ⁶ and R ⁷ may be the same or different,
It represents a hydrogen atom, an alkyl, an aralkyl, an aryl or a halogeno group, preferably a hydrogen atom, an alkyl having 1 to 8 carbons or an aryl group having 6 to 15 carbons.
Also, two of L ¹⁰ , R ⁶ and R ⁷ may combine to form a ring. L ¹¹ and L ¹² may be the same or different,
It represents a single bond, a double bond, or a divalent aliphatic hydrocarbon group, and preferably represents a single bond, a double bond, or a methylene group. A represents a mononuclear or polynuclear aromatic ring. It preferably represents an aromatic ring having 6 to 18 carbon atoms.

Specific examples of the compound represented by the formula (5), (6) or (7) include the following.
That is, pyromellitic dianhydride, 3,3 ', 4,
4'-benzophenonetetracarboxylic dianhydride, 3,
3 ′, 4,4′-diphenyltetracarboxylic dianhydride, 2,3,6,7-naphthalenetetracarboxylic dianhydride, 1,4,5,8-naphthalenetetracarboxylic dianhydride, 4, 4'-sulfonyl diphthalic dianhydride,
2,2-bis (3,4-dicarboxyphenyl) propane dianhydride, bis (3,4-dicarboxyphenyl) ether dianhydride, 4,4 ′-[3,3 ′-(alkylphosphoryldiphenylene) ) -Bis (iminocarbonyl)]
Diphthalic dianhydride,

Aromatic tetracarboxylic dianhydrides such as adducts of hydroquinone diacetate and trimetic anhydride, and adducts of diacetyldiamine and trimetic anhydride;
5- (2,5-dioxotetrahydrofuryl) -3-methyl-3-cyclohexene-1,2-dicarboxylic anhydride (Dai Nippon Ink Chemical Industry Co., Ltd., Epicron B-4)
Alicyclic tetracarboxylic acids such as 400), 1,2,3,4-cyclopentanetetracarboxylic dianhydride, 1,2,4,5-cyclohexanetetracarboxylic dianhydride and tetrahydrofurantetracarboxylic dianhydride Acid dianhydride; aliphatic tetracarboxylic dianhydrides such as 1,2,3,4-butanetetracarboxylic dianhydride and 1,2,4,5-pentanetetracarboxylic dianhydride;

These (c) tetracarboxylic dianhydrides are ring-opened by the (d) diol compound, and the reaction product of the structural unit derived from the resulting compound and (a) the isocyanate compound is Forming the basic skeleton of the polyurethane resin having a carboxyl group according to the present invention. As a method for introducing a structural unit derived from a compound obtained by ring-opening the (c) tetracarboxylic dianhydride with the (d) diol compound into the polyurethane resin, for example, the following method is available. a) A method of reacting (c) an alcohol-terminated compound obtained by ring-opening a tetracarboxylic dianhydride with a (d) diol compound and (a) a diisocyanate compound. b) ring opening of the diisocyanate compound (a) with the diol compound (d), the resulting compound is reacted under excess conditions, and the alcohol-terminated urethane compound obtained is reacted with (c) tetracarboxylic acid diacid. A method of reacting with an anhydride.

The (d) diol compounds used when (c) the tetracarboxylic dianhydride is used in the synthesis of the (A) specific polyurethane resin according to the present invention are specifically as follows: Is included. That is, ethylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, propylene glycol, dipropylene glycol, polyethylene glycol, polypropylene glycol, neopentyl glycol, 1,3-butylene glycol, 1,6-hexanediol, 2-butene- 1,4-diol, 2,2,4-
Trimethyl-1,3-pentanediol, 1,4-bis-β-hydroxyethoxycyclohexane, cyclohexanedimethanol, tricyclodecanedimethanol, hydrogenated bisphenol A, hydrogenated bisphenol F, ethylene oxide adduct of bisphenol A, bisphenol A propylene oxide adduct, bisphenol F ethylene oxide adduct, bisphenol F propylene oxide adduct, hydrogenated bisphenol A ethylene oxide adduct, hydrogenated bisphenol A propylene oxide adduct, hydroquinone dihydroxyethyl ether, p- Xylylene glycol, dihydroxyethyl sulfone, bis (2-hydroxyethyl) -2,4
-Tolylene dicarbamate, 2,4-tolylene-bis (2-hydroxyethylcarbamide), bis (2-hydroxyethyl) -m-xylylenedicarbamate, bis (2-hydroxyethyl) isophthalate, and the like.

-Other diol compounds- Further, in the synthesis of the specific polyurethane resin (A) according to the present invention, other diol compounds having no carboxyl group can be used in combination. As the diol compound, broadly, a polyether diol compound, a polyester diol compound, a polycarbonate diol compound and the like can be mentioned. As the polyether diol compound,
Examples include compounds represented by formulas (8), (9), (10), (11), and (12), and random copolymers of ethylene oxide and propylene oxide each having a hydroxyl group at a terminal.

[0036]

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In the formula, a, b, c, d, e, f and g each represent an integer of 2 or more, preferably an integer of 2 to 100. R ¹ represents a hydrogen atom or a methyl group;
Represents the following groups.

[0038]

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Specific examples of the polyether diol compounds represented by formulas (8) and (9) include the following. That is, diethylene glycol, triethylene glycol, tetraethylene glycol, pentaethylene glycol, hexaethylene glycol, heptaethylene glycol, octaethylene glycol, di-
1,2-propylene glycol, tri-1,2-propylene glycol, tetra-1,2-propylene glycol, hexa-1,2-propylene glycol, di-1,
3-propylene glycol, tri-1,3-propylene glycol, tetra-1,3-propylene glycol,
Di-1,3-butylene glycol, tri-1,3-butylene glycol, hexa-1,3-butylene glycol, polyethylene glycol having a weight average molecular weight of 1,000, polyethylene glycol having a weight average molecular weight of 1500, and polyethylene glycol having a weight average molecular weight of 2,000 Polyethylene glycol having a weight average molecular weight of 3000, polyethylene glycol having a weight average molecular weight of 7,500, polypropylene glycol having a weight average molecular weight of 400, polypropylene glycol having a weight average molecular weight of 700, polypropylene glycol having a weight average molecular weight of 1,000, and polypropylene glycol having a weight average molecular weight of 2,000. Polypropylene glycol having an average molecular weight of 3000, polypropylene glycol having a weight average molecular weight of 4000, and the like.

Specific examples of the polyether diol compound represented by the formula (10) include the following. For example, PTMG650 manufactured by Sanyo Chemical Industries, Ltd.,
PTMG1000, PTMG2000, PTMG300
It is 0 and so on.

Specific examples of the polyether diol compound represented by the formula (11) include the following. For example, New Pole PE manufactured by Sanyo Chemical Industries, Ltd.
-61, New Pole PE-62, New Pole PE-
64, New Pole PE-68, New Pole PE-7
1, New Pole PE-74, New Pole PE-7
5, New Pole PE-78, New Pole PE-10
8, New Pole PE-128, New Pole PE-6
1 mag.

Specific examples of the polyether diol compound represented by the formula (12) include the following. For example, New Pole BP manufactured by Sanyo Chemical Industries, Ltd.
E-20, New Pole BPE-20F, New Pole BPE-20NK, New Pole BPE-20T, New Pole BPE-20G, New Pole BPE-40,
New Pole BPE-60, New Pole BPE-10
0, New Pole BPE-180, New Pole BPE
-2P, Newpole BPE-23P, Newpole B
PE-3P, Newpole BPE-5P and the like.

Specific examples of the random copolymer of ethylene oxide and propylene oxide having a hydroxyl group at the terminal include the following. For example, new pole 50HB-100, new pole 50HB-260, new pole 50HB-40 manufactured by Sanyo Chemical Industries, Ltd.
0, New Pole 50HB-660, New Pole 50
HB-2000, Newpole 50HB-5100 and the like.

Examples of the polyester diol compound include compounds represented by formulas (13) and (14).

[0045]

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In the formula, L ² , L ³ and L ⁴ may be the same or different and each represents a divalent aliphatic or aromatic hydrocarbon group, and L ⁵ represents a divalent aliphatic hydrocarbon group. . Preferably, L ² , L ³ , and L ⁴ each represent an alkylene group or an arylene group, and L ⁵ represents an alkylene group. L ² ,
In L ³ , L ⁴ and L ⁵ , other functional groups which do not react with the isocyanate group, for example, ether, carbonyl, ester, cyano, olefin, urethane, amide, ureido group or halogen atom may be present. n1 and n2 are each an integer of 2 or more, and preferably an integer of 2 to 100.

As the polycarbonate diol compound, there is a compound represented by the formula (15).

[0048]

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In the formula, L ⁶ may be the same or different and represents a divalent aliphatic or aromatic hydrocarbon group. Preferably, L ⁶ represents an alkylene group or an arylene group. In L ⁶ , other functional groups that do not react with the isocyanate group,
For example, ethers, carbonyls, esters, cyano, olefins, urethanes, amides, ureido groups or halogen atoms may be present. n3 is an integer of 2 or more, and preferably an integer of 2 to 100.

Specific examples of the diol compound represented by the formula (13), (14) or (15) include the following. N in a specific example is an integer of 2 or more.

[0051]

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[0052]

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[0053]

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[0054]

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Further, similarly to the diol compound, the amino group-containing compounds represented by the following formulas (16) and (17) are reacted with the diisocyanate compound represented by the general formula (4) to form a urea structure. May be incorporated into the structure of the polyurethane resin.

[0056]

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In the formula, R ¹⁸ and R ¹⁹ may be the same or different, and each represents a hydrogen atom, a substituent (eg, alkoxy, a halogen atom (—F, —Cl, —Br, —I), an ester, An alkyl group, an aralkyl group, or an aryl group, which may have a hydrogen atom, and preferably a carbon atom having 1 to 8 carbon atoms which may have a carboxyl group as a substituent. Alkyl represents an aryl group having 6 to 15 carbon atoms. L ²⁴ represents a substituent (eg, alkyl, aralkyl, aryl, alkoxy, aryloxy, halogen atom (—F, —Cl, —Br, —
I) and carboxyl groups. A) a divalent aliphatic hydrocarbon group, an aromatic hydrocarbon group or a heterocyclic group which may have If necessary, other functional groups which do not react with isocyanate groups in L ²⁴ , such as carbonyl,
It may have an ester, urethane, amide group or the like. Two of R ¹⁸ , L ²⁴ and R ¹⁹ may be bonded to each other to form a ring.

Specific examples of the compounds represented by formulas (16) and (17) include the following. That is, ethylenediamine, propylenediamine, tetramethylenediamine, pentamethylenediamine, hexamethylenediamine, heptamethylenediamine, octamethylenediamine, dodecamethylenediamine, propane-
1,2-diamine, bis (3-aminopropyl) methylamine, 1,3-bis (3-aminopropyl) tetramethylsiloxane, piperazine, 2,5-dimethylpiperazine, N- (2-aminoethyl) piperazine, 4-amino-2,2-6,6-tetramethylpiperidine, N, N
-Dimethylethylenediamine, lysine, L-cystine,
Aliphatic diamine compounds such as isophorone diamine;
o-phenylenediamine,

M-phenylenediamine, p-phenylenediamine, 2,4-tolylenediamine, benzidine, o
-Ditoluidine, o-dianisidine, 4-nitro-m-
Phenylenediamine, 2,5-dimethoxy-p-phenylenediamine, bis- (4-aminophenyl) sulfone, 4-carboxy-o-phenylenediamine, 3-carboxy-m-phenylenediamine, 4,4′-diaminophenylether Aromatic diamine compounds such as 1,8-naphthalenediamine and the like; 2-aminoimidazole, 3-aminotriazole, 5-amino-1H-tetrazole, 4-aminopyrazole, 2-aminobenzimidazole, 2-amino-5 -Carboxy-triazole, 2,4-diamino-6-methyl-S-triazine,
Heterocyclic amine compounds such as 2,6-diaminopyridine, L-histidine, DL-tryptophan, adenine and the like; ethanolamine, N-methylethanolamine,
N-ethylethanolamine,

1-amino-2-propanol, 1-amino-3-propanol, 2-aminoethoxyethanol, 2-aminothioethoxyethanol, 2-amino-
2-methyl-1-propanol, p-aminophenol, m-aminophenol, o-aminophenol, 4
-Methyl-2-aminophenol, 2-chloro-4-aminophenol, 4-methoxy-3-aminophenol, 4-hydroxybenzylamine, 4-amino-1-
Naphthol, 4-aminosalicylic acid, 4-hydroxy-
Amino alcohol or aminophenol compounds such as N-phenylglycine, 2-aminobenzyl alcohol, 4-aminophenethyl alcohol, 2-carboxy-5-amino-1-naphthol, L-tyrosine and the like.

(E-1) A diol compound having a polymerizable or crosslinkable functional group The polymerizable or crosslinkable functional group contained in the silicone rubber layer (E-1) constituting the (A) specific polyurethane resin according to the present invention. In the diol compound having the above, examples of the polymerizable or crosslinkable functional group include a hydroxyl group, an ethylenically unsaturated bond group, an amino group, a thiol group, an acetylene group, and a carbonyl group. In the present invention, more preferred as the polymerizable or crosslinkable functional group is an ethylenically unsaturated bond group. Examples of the diol compound having an ethylenically unsaturated bond group include compounds represented by formulas (18-1), (18-2), and (1).
And a structural unit represented by at least one of the diol compounds of 8-3).

[0062]

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In the formula, R is a hydrogen atom, a substituent (for example, cyano, nitro, halogen atom, (-F, -Cl, -B
_{r, -I), - CONH 2} , -COOR 3, -OR 3, -
^{NHCONHR 3, -NHCOOR 3, -NHCOR 3} ,
—OCONHR ³ (where R ³ represents an alkyl group having 1 to 10 carbon atoms and an aralkyl group having 7 to 15 carbon atoms). Represents an alkyl, aralkyl, aryl, alkoxy, aryloxy group which may have a hydrogen atom, preferably an alkyl having 1 to 8 carbon atoms,
It represents an aryl group having 6 to 15 carbon atoms. R ′ represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms.

L^{twenty five}, L²⁶, L²⁷Are the same but different
May be a single bond, a substituent (eg, alkyl,
Aralkyl, aryl, alkoxy, halogeno
preferable. ) May have a divalent aliphatic or aromatic
Represents an aromatic hydrocarbon group and preferably has 1 to 20 carbon atoms.
Alkylene group, arylene group having 6 to 15 carbon atoms, and
It preferably represents an alkylene group having 1 to 8 carbon atoms. Also
L if necessary^{twenty five}, L ²⁶, L²⁷With isocyanate group inside
Other functional groups that do not react, such as carbonyl, ester,
Has urethane, amide, ureide, ether groups
Is also good. Note that R ^Two, L^{twenty five}, L²⁶, L²⁷2 or 3 of
May combine with each other to form a ring. Ar is a substituent
A trivalent aromatic hydrocarbon group which may have
More preferably, it represents an aromatic group having 6 to 15 carbon atoms.

Formula (18-1), (18-2) or (18)
Specific examples of the diol compound represented by -3) include the following, but the present invention is not limited thereto. Note that n in the specific examples is an integer of 1 or more.

[0066]

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[0067]

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[0068]

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The specific polyurethane resin (A) according to the present invention is synthesized by adding a known catalyst having an activity corresponding to the respective reactivities of the above-mentioned isocyanate compound and diol compound, followed by heating. The molar ratio between the diisocyanate and the diol compound used is preferably 0.7:
1 to 1.3: 1. At this time, generally, when the amount of diisocyanate is excessive, a large amount of isocyanate group remains at the polymer terminal, and when the amount of diol component is excessive, a polyurethane resin having an alcohol group remaining at the polymer terminal is formed.

Among the diol compounds of the carboxyl group-containing polyurethane resin used in the present invention, the carboxyl group-containing diol component is 50% of all diol components.
% To 100%, preferably 60% to 95%. The content of the specific polyurethane resin having a carboxyl group used in the present invention is 30 to 90% by weight, preferably 40 to 85% by weight, based on all solids constituting the photothermal conversion layer.
%, More preferably 50 to 80% by weight.

Since the specific polyurethane resin (A) thus synthesized has an ethylenically unsaturated bonding group,
The cross-linking agent or addition-reactive functional group contained in the silicone rubber layer described below and the ethylenically unsaturated bonding group effectively form an interaction at the layer interface, thereby increasing the adhesive strength between the light-to-heat conversion layer and the silicone rubber layer. Is presumed to enhance the storage stability.

(E-2) Introduction of a Structural Unit Having a Polymerizable or Crosslinkable Functional Group (A) The specific polyurethane resin synthesized as described above, or synthesized from the above (A) to (D) For a polyurethane resin having only a carboxyl group, a polymerizable or crosslinkable functional group can be introduced to the polymer terminal by the following method. Examples of the polymerizable or crosslinkable functional group include a hydroxyl group, an ethylenically unsaturated bond group, an amino group, a thiol group, an acetylene group, and a carbonyl group. In the present invention, more preferred as the polymerizable or crosslinkable functional group is an ethylenically unsaturated bond group.
Hereinafter, a method for introducing an ethylenically unsaturated bond group into a polyurethane resin terminal will be described.

As a method for introducing an ethylenically unsaturated bond group into the terminal of the polyurethane resin, a method (a) for introducing a terminal isocyanate polyurethane resin and a method (b) for introducing a terminal alcohol into a polyurethane resin shown below. is there. Preferably, the molar ratio of the diisocyanate compound to the diol compound is set to 1: 1 to 1.3: 1, a polyurethane resin is synthesized so that the polymer terminal is an isocyanate group, and a compound having an ethylenically unsaturated bond group at the terminal isocyanate Is introduced.

(A) Method for Introducing into Isocyanate-terminated Polyurethane Resin When introducing into a polyurethane resin having an isocyanate group remaining at a terminal, a compound represented by the following general formula (19-1) is reacted to form a terminal isocyanate group. A polyurethane resin having an ethylenically unsaturated bond group can be obtained.

[0075]

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In the formula, X represents a hydroxyl group, an amino group, a monosubstituted amino group, a thiol group, a carboxyl group, or an epoxy group; R represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms; And an arylene group. In L, other functional groups which do not react with the isocyanate group, for example, ether, carbonyl, ester, cyano, olefin, urethane, amide, ureide group or halogen atom may be present.

These compounds can be easily introduced into the polyurethane resin terminals by performing a polymerization reaction in a form in which isocyanate groups remain at the terminals under the condition of excess diisocyanate, and then adding and treating these compounds to the reaction solution. it can. Hereinafter, specific examples of the compound represented by the formula (19-1) are shown, but the present invention is not limited thereto.
Note that n in the specific examples is an integer of 1 or more.

[0078]

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(B) Method of Introducing into Terminal Alcohol Polyurethane Resin When introducing into a polyurethane resin in which an alcohol group remains at the terminal, a compound represented by the following general formula (19-2) is reacted to give a terminal. A polyurethane resin having an ethylenically unsaturated bond group can be obtained.

[0080]

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In the formula, Y represents an epoxy group, an isocyanate group, a carboxyl group, a hydroxyl group, a thiol group, a halogen atom, R represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, L represents an alkylene group or an arylene group. Represents a group.
In L, other functional groups that do not react with isocyanate groups, such as ether, carbonyl, ester, cyano,
Olefins, urethanes, amides, ureido groups or halogen atoms may be present.

These compounds can be easily introduced by a known reaction. For example, when Y is an epoxy group or an isocyanate group, a polyurethane resin having an ethylenically unsaturated bond group at a terminal can be easily obtained by treating a polyurethane resin having a terminal alcohol with a known catalyst. Hereinafter, specific examples of the compound represented by the formula (19-2) are shown, but the present invention is not limited thereto. Note that n in the specific examples is an integer of 1 or more.

[0083]

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The polymer (A) having an ethylenically unsaturated bonding group at the polymer terminal and a carboxyl group synthesized using the method of introducing an ethylenically unsaturated bonding group at the terminal of the polyurethane resin described above. Since the specific polyurethane resin has an unsaturated bond in a portion of the polymer terminal where the mobility of the polymer molecular chain is relatively high, a crosslinking agent or a crosslinking agent contained in a silicone rubber layer to be described later, rather than a resin having an unsaturated bond in a main chain. It is presumed that the interaction between the addition-reactive functional group and the layer interface is more effectively formed, and the storage stability is further enhanced by the effect of increasing the adhesive force between the light-heat conversion layer and the silicone rubber layer.

(B) Photothermal conversion agent As the photothermal conversion agent used in the present invention, a known substance having a function of converting laser light used for writing into heat (photothermal conversion function) can be used. When the light source is an infrared laser, various organic and inorganic materials that absorb light having a wavelength used for writing, such as an infrared absorbing pigment, an infrared absorbing dye, an infrared absorbing metal, and an infrared absorbing metal oxide, can be used. Has been known for some time.

Examples of these light-to-heat converting agents include various carbon blacks such as acidic carbon black, basic carbon black and neutral carbon black, various carbon blacks surface-modified or surface-coated to improve dispersibility, and nigrosine. , Black pigments such as aniline black and cyanine black, phthalocyanine, naphthalocyanine-based green pigments, carbon graphite, aluminum, iron powder, diamine-based metal complexes, dithiol-based metal complexes, phenolthiol-based metal complexes, and mercaptophenol-based metal complexes , Aryl aluminum metal salts, inorganic compounds containing water of crystallization, copper sulfate, chromium sulfide, silicate compounds, and metal oxides such as titanium oxide, vanadium oxide, manganese oxide, iron oxide, cobalt oxide, tungsten oxide, indium tin oxide Etc., hydroxides of these metals, sulfates, further bismuth, tin, tellurium, iron, adding an additive such as metal powder of aluminum preferred. Besides this,
"Infrared sensitizing dyes" as organic dyes (Plenu by Matsuoka)
m Press, New York, NY (199
0)), US Pat. No. 4,833,124, EP-32192.
No. 3, US Pat. No. 4,772,583, US-494
No. 2141, U.S. Pat. No. 4,948,776, U.S. Pat.
No. 4,948,777, US Pat. No. 4,948,778,
US Pat. No. 4,950,639, US Pat. No. 4,912,083, US Pat. No. 4,952,552, US Pat.
Examples include various compounds described in the specification such as Japanese Patent Publication No. 29, but are not limited thereto.

Among these, carbon black is particularly preferred from the viewpoints of light-to-heat conversion rate, economy, and handleability. Carbon black includes furnace black, lamp black, channel black,
Roll black, disc black, thermal black, acetylene black, etc. are classified, furnace black is variously used in terms of particle size and other aspects are commercially available, and it is preferably used because it is commercially inexpensive. You.

The degree of aggregation of the primary particles of the carbon black affects the plate material sensitivity. When the degree of aggregation of the primary particles of carbon black is high (having a high structure structure), the blackness of the plate material does not increase when compared with the same amount of addition, and as a result, the absorption rate of the laser beam decreases, and as a result, The sensitivity decreases. In addition, the viscosity of the coating solution for the light-to-heat conversion layer increases due to the aggregation of the particles, and the coating solution becomes thixotropy, so that the handling of the coating solution becomes difficult and the coating film becomes nonuniform. On the other hand, when the oil absorption is low, the dispersibility of the carbon black decreases, and the plate material sensitivity also tends to decrease. The degree of agglomeration of the primary particles of the carbon black can be compared by a value called oil absorption. The higher the oil absorption, the higher the degree of aggregation, and the lower the oil absorption, the lower the degree of aggregation. That is, it is preferable to use carbon black having an oil absorption in the range of 20 to 200 ml / 100 g, and more preferably 40 to 120 ml / 100 g.

Further, carbon black having various particle sizes is commercially available, and the particle size of the primary particles also affects the plate material sensitivity. If the average particle size of the primary particles is too small, the light-to-heat conversion layer itself becomes transparent and cannot efficiently absorb laser light, resulting in a reduction in plate material sensitivity. If the particle size is too large, the particles are not dispersed at a high density, the blackness of the light-to-heat conversion layer is not increased, and the laser light cannot be efficiently absorbed, and the plate material sensitivity is also lowered. That is, it is preferable to use carbon black having an average primary particle diameter of 10 to 50 nm, more preferably 15 to 50 nm.
４０40 nm.

Further, conductive carbon black is used.
Thereby, plate material sensitivity can be improved. this
When the electrical conductivity is 0.01Ω^-1cm^-1~ 100Ω^-1
cm ^-1Is preferably in the range of, more preferably
0.1Ω^-1cm^-1-10Ω^-1cm^-1It is. Specifically
Are "CONDUCTEX" 40-220, "COND
UCTEX "975 BEADS," CONDUCTE
X "900BEADS," CONDUCTEX "SC,
"BATTERY BLACK" (Colombian Carbo
# 3000 (manufactured by Mitsubishi Chemical Corporation),
"Denka Black" (manufactured by Denki Kagaku Kogyo KK), "VU
LCAN XC-72R "(Cabot)
It is preferably used.

As described above, the light-to-heat conversion layer of the present invention contains nitrogen by the thermal decomposition of nitro compounds such as nitrocellulose, ammonium nitrate, potassium nitrate and sodium nitrate, and azo compounds, diazo compounds and hydrazine derivatives. It is preferable from an environmental point of view not to include a self-oxidizing nitrogen-containing compound that generates an oxide. The amount of the light-to-heat conversion agent used in the present invention is 5 to 70% by weight, preferably 10 to 50% by weight, based on all solids constituting the light-to-heat conversion layer. When the addition amount is 5% by weight or less, the sensitivity decreases, and when the addition amount is 70% by weight or more, the film strength of the light-to-heat conversion layer decreases, and the adhesion to an adjacent layer also decreases.

In the light-to-heat conversion layer according to the present invention, a known binder that dissolves or disperses the light-to-heat conversion material may be used in addition to the above components (A) and (B). Examples of these include polymethyl methacrylate, acrylic esters such as polybutyl methacrylate, homo- and copolymers of methacrylic esters, polystyrene,
Homopolymers or copolymers of styrene monomers such as α-methylstyrene. Various synthetic rubbers such as isoprene and styrene-butadiene; homopolymers of vinyl esters such as polyvinyl acetate; copolymers such as vinyl acetate-vinyl chloride; and various condensation polymers such as polyurea, polyurethane resin, polyester, and polycarbonate. And “J. Imaging Sci., P59-6.
4, 30 (2), (1986) (Frechet et al.) "
And "Polymersin Electronics"
(Symposium Series, P11, 24
2, T. Davidson, Ed. , ACS Wash
inton, DC (1984) (Ito, Wills)
on) "," Microelectronic Eng "
inering, P3-10, 13 (1991)
(E. Reichmanis, LF Thompso
n)), a binder or the like used in a so-called “chemical amplification system” can be used. The addition amount thereof is 1 to 30% by weight based on the total solid content of the light-to-heat conversion layer.
5 to 20% by weight.

In the light-to-heat conversion layer according to the present invention, other known additives can be used in combination according to the purpose as long as the effects of the present invention are not impaired. These additives improve the mechanical strength of the light-to-heat conversion layer, improve the laser recording sensitivity, improve the dispersibility of the dispersion in the light-to-heat conversion layer, and improve the support, the primer layer and the silicone rubber layer. And the like are added according to various purposes such as improving the adhesion to an adjacent layer.

For example, in order to improve the mechanical strength of the light-to-heat conversion layer, various crosslinking agents for curing the light-to-heat conversion layer may be added. By adding this crosslinking agent, the light-to-heat conversion layer has a cross-linked structure, but in the waterless lithographic printing plate precursor of the present invention, a polyurethane resin having a carboxyl group forming the light-to-heat conversion layer is used. Therefore, this carboxyl group becomes a reaction site at the time of crosslinking,
A dense crosslinked structure is formed. For this reason, even when development is performed using a developing solution containing a solvent, there is an advantage that a decrease in the adhesion of the non-image area can be effectively prevented.

The reaction efficiency at the interface between the silicone rubber layer and the light-to-heat conversion layer may be slightly reduced by the addition of such a crosslinking agent, but this is a preferred embodiment of the present invention (the light-to-heat conversion layer is The reactivity between the ethylenically unsaturated bond groups (introduced in the constituent polyurethane resin) and these crosslinking agents is low, and the effect of increasing the mechanical strength of the light-to-heat conversion layer on printing durability, Considering the effect of the effect of improving the adhesiveness with the silicone rubber layer on the storage stability, it is considered that there is almost no problem.

The crosslinking agent that can be used is not particularly limited, and a known crosslinking agent can be appropriately selected and used.
For example, a combination of a polyfunctional isocyanate compound or a polyfunctional epoxy compound and the like, a hydroxyl group-containing compound, a carboxylic acid compound, a thiol-based compound, an amine-based compound, a urea-based compound, and the like are exemplified, but not limited thereto. . The amount of the crosslinking agent used in the present invention is 1 to 30% by weight based on the total solid content of the light-to-heat conversion layer.
-20% by weight. If the addition amount is less than 1% by weight, the effect of the addition of the crosslinking agent is insufficient, and if it exceeds 30% by weight, the film strength of the light-to-heat conversion layer becomes too strong and the plate material sensitivity is lowered.

When a pigment such as carbon black is used as the photothermal conversion agent, various pigment dispersants can be used as additives to improve the degree of dispersion of the pigment. The amount of the pigment dispersant used in the present invention is 1 to 70% by weight, preferably 5 to 50% by weight, based on the photothermal conversion agent.
It is. When the addition amount is less than 1% by weight, the effect of improving the degree of pigment dispersion is small and the plate material sensitivity is lowered, and when it exceeds 70% by weight, the adhesion to the adjacent layer is reduced.

In order to improve the adhesion to an adjacent layer, a known adhesion improver such as a silane coupling agent and a titanate coupling agent can be added. The addition amount of the adhesion improver used in the present invention is 5 to 30% by weight based on the total solid content of the light-to-heat conversion layer, preferably,
It is 10 to 20% by weight.

Further, in order to improve the coating property of the coating solution for the light-to-heat conversion layer, a surfactant such as a fluorine-based surfactant and a nonionic surfactant can be used as an additive.
The amount of the surfactant used in the present invention is 0.01 to 3% by weight, preferably 0.05 to 1% by weight, based on the total solid content of the photothermal conversion layer. In addition, various additives can be used as needed.

The film thickness of the photothermal conversion layer of the present invention is 0.05 to
It is 10 μm, preferably 0.1-5 μm. If the thickness of the light-to-heat conversion layer is less than 0.05 μm, sufficient optical density cannot be obtained, and the laser recording sensitivity is lowered. Also, uniform film formation becomes difficult, and the image quality is deteriorated. .

[Silicone Rubber Layer] The ink-repellent silicone rubber layer used in the present invention is formed by reacting a silicone rubber film on the light-to-heat conversion layer. Specifically, it is preferable to cure the condensation type silicone using a crosslinking agent or to form the addition type silicone by addition polymerization using a catalyst. When the condensation type silicone is used, (b) 3 parts of the condensation type crosslinking agent is added to 100 parts by weight of the diorganopolysiloxane.
It is preferable to use a composition containing up to 70 parts by weight and (c) 0.01 to 40 parts by weight of the catalyst.

The diorganopolysiloxane of the component (a) is a polymer having a repeating unit represented by the following general formula. R ¹ and R ² are an alkyl group having 1 to 10 carbon atoms, a vinyl group, or an aryl group, and may have other suitable substituents. Generally, R ¹ and R ²
Is preferably a methyl group, a vinyl halide group, a halogenated phenyl group or the like.

[0103]

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It is preferable to use such a diorganopolysiloxane having hydroxyl groups at both ends. The component (a) has a number average molecular weight of 3,000 to 6,
00,000, more preferably 5,000 to 1
00,000. The crosslinking agent of the component (b) may be any one as long as it is of a condensation type, but is preferably one represented by the following general formula.

R ¹ _m · Si · X _n (m + n = 4, n is 2 or more)

Here, R ¹ has the same meaning as R ¹ described above, and X represents a halogen atom such as Cl, Br, I, a hydrogen atom, a hydroxyl group, or an organic substituent shown below.

[0107]

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In the formula, R ³ represents an alkyl group having 1 to 10 carbon atoms and an aryl group having 6 to 20 carbon atoms, and R ⁴ and R ⁵ represent an alkyl group having 1 to 10 carbon atoms. As component (c),
Metal carboxylate such as tin, zinc, lead, calcium, manganese and the like, for example, known catalysts such as dibutyl laurate, lead octylate, lead naphthenate and the like, and chloroplatinic acid and the like can be mentioned.

When using an addition type silicone,
(E) 0.1 to 25 parts by weight of an organohydrogenpolysiloxane and (f) 0.00001 to 1 part by weight of an addition catalyst based on 100 parts by weight of a diorganopolysiloxane having an addition-reactive functional group. Is preferably used.

The diorganopolysiloxane having an addition-reactive functional group of the component (d) is an organopolysiloxane having at least two alkenyl groups (more preferably, vinyl groups) directly bonded to silicon atoms in one molecule. The alkenyl group may be at the molecular weight terminal or in the middle, and may have a substituted or unsubstituted alkyl or aryl group having 1 to 10 carbon atoms as an organic group other than the alkenyl group. The component (d) may optionally have a small amount of a hydroxyl group. Component (d) has a number average molecular weight of 3,000 to 600,000, more preferably
5,000 to 100,000.

Component (e) includes polydimethylsiloxane having hydrogen groups at both ends, α, ω-dimethylpolysiloxane, and (methylsiloxane)-
(Dimethylsiloxane) copolymer, cyclic polymethylsiloxane, polymethylsiloxane having trimethylsilyl groups at both terminals, dimethylsiloxane having trimethylsilyl groups at both terminals)-(methylsiloxane) copolymer, and the like.

The component (f) is arbitrarily selected from known polymerization catalysts, and is particularly preferably a platinum-based compound, such as platinum alone, platinum chloride, chloroplatinic acid, and olefin-coordinated platinum. .

For the purpose of controlling the curing rate of the silicone rubber layer in these compositions, organopolysiloxanes containing vinyl groups such as tetracyclo (methylvinyl) siloxane, alcohols containing carbon-carbon triple bonds, acetone, methyl ethyl ketone It is also possible to add a crosslinking inhibitor such as methanol, ethanol, propylene glycol monomethyl ether and the like. In the silicone rubber layer, if necessary, fine powders of inorganic substances such as silica, calcium carbonate and titanium oxide, silane coupling agents, adhesion aids such as titanate coupling agents and aluminum coupling agents, and photopolymerization. An initiator may be added.

[0114] thickness of the ink repellent silicone rubber layer in the present invention is preferably 0.5 to 5 g / m ² as dry film thickness, and more preferably from 1 to 3 g / m ^2. When the film thickness is less than 0.5 g / m ² , the ink repellency decreases,
There are problems such as easy damage, and when it is more than 5 g / m ² , image reproducibility is deteriorated.

Further, in the waterless planographic printing plate precursor according to the present invention, various silicone rubber layers may be further formed on the silicone rubber layer for the purpose of improving printing durability, scratch resistance, image reproducibility and stain resistance. It may be coated.

The silicone rubber layer of the waterless planographic printing plate precursor according to the present invention is soft and easily scratched. For the purpose of protecting the surface, a transparent film such as a polyester such as polyethylene terephthalate or polyethylene naphthalate is formed on the silicone rubber layer. Laminate, polyethylene, polypropylene, polystyrene, polyvinyl chloride, polyvinylidene chloride, polyvinyl alcohol, cellophane, etc.
A polymer coating may be applied. These films may be used after being stretched. Further, the surface may be subjected to mat processing, but from the viewpoint of image reproducibility, the case without the mat processing is preferable in the present invention.

The silicone rubber layer used in the present invention has been described above. The silicone rubber layer composed of condensation type silicone has a crosslinking agent, and the silicone rubber layer composed of addition type silicone has an addition reaction in silicone. The functional functional group and the polymerizable or crosslinkable functional group in the light-to-heat conversion layer used in the present invention described above each form an effective interaction at the layer interface, and the light-to-heat conversion layer and the silicone rubber layer Adhesive strength can be increased, and as a result, storage stability can be increased.

[Support] The waterless lithographic printing plate precursor according to the present invention has such a flexibility that it can be set in an ordinary printing press.
At the same time, it must withstand the load applied during printing. Therefore, typical supports that can be used for the waterless lithographic printing plate precursor of the present invention include coated paper, metal plates such as aluminum, plastic films such as polyethylene terephthalate, rubber, and composites thereof. And more preferably coated paper, aluminum plate, containing aluminum (eg, silicon, copper,
Alloys with aluminum and metals such as manganese, magnesium, chromium, zinc, lead, bismuth and nickel) alloy plates and plastic films. Further, two or more of these exemplified supports may be laminated or adhered with an adhesive or the like.

These supports have improved surface adhesion,
Various surface treatments such as a corona discharge treatment, a matt-easy adhesion treatment, and an antistatic treatment may be performed to improve the antistatic property. The thickness of the support is suitably from 25 μm to 3 mm, preferably from 75 μm to 500 μm, but the optimum thickness varies depending on the type of support used and printing conditions. Generally, 100 μm to 300 μm is most preferable.

[Primer layer] In the present invention, a primer layer can be provided between the support and the photothermal conversion layer. As the primer layer used in the present invention, various layers can be used for improving the adhesion between the substrate and the light-to-heat conversion layer and improving the printing characteristics. For example, JP
Various types of photosensitive polymers as disclosed in JP-A-2-2903 are exposed and cured before laminating a photosensitive resin layer, and epoxy resins disclosed in JP-A-62-50760 are used. Heat cured, JP 6
Japanese Patent Application Laid-Open No. 3-133151 discloses a hardened gelatin disclosed in Japanese Patent Application Laid-Open No. 3-133151, a device using a urethane resin and a silane coupling agent disclosed in Japanese Patent Application Laid-Open No. 3-200965, and Japanese Patent Application Laid-Open No. 3-273248. And the like using a urethane resin disclosed in US Pat. In addition, those obtained by hardening gelatin or casein are also effective.

Further, for the purpose of softening the primer layer, a polyurethane resin having a glass transition temperature of room temperature or lower, polyamide, styrene / butadiene rubber, carboxy-modified styrene / butadiene rubber, acrylonitrile / butadiene rubber having a glass transition temperature of not more than room temperature. And polymers such as carboxy-modified acrylonitrile / butadiene rubber, polyisoprene, acrylate rubber, polyethylene, chlorinated polyethylene, and chlorinated polypropylene. The addition ratio is arbitrary, and the primer layer may be formed only by the additive as long as the film layer can be formed.

In addition, these primer layers may have a dye, a pH indicator, a printing-out agent, a photopolymerization initiator, and an adhesion assistant (for example, a polymerizable monomer, a diazo resin, a silane coupling agent, Additives such as titanate coupling agents and aluminum coupling agents), pigments, silica powder and titanium oxide powder can also be included, and after application, they can be cured by exposure. Generally, the coating amount of the primer layer is 0.1 to 10 by dry weight.
g / m ² is suitable, preferably 0.3 to 7 g.
/ M ² , more preferably 0.5 to 5 g / m ² . The waterless planographic printing plate precursor of the invention is obtained by forming a light-to-heat conversion layer and a silicone rubber layer after providing a primer layer on the support as desired.

The waterless planographic printing plate precursor of the invention is exposed imagewise and then developed to obtain a waterless planographic printing plate. In the present invention, the laser used to expose the waterless lithographic printing plate precursor has an exposure amount necessary to cause a decrease in adhesion sufficient to peel and remove the silicone rubber layer from the support. There is no particular limitation as long as it gives, a gas laser such as an Ar laser, a carbon dioxide laser, a solid laser such as a YAG laser,
Then, a semiconductor laser or the like can be used. Normal output is 50
A laser of mW class or higher is required. Semiconductor lasers and semiconductor-pumped solid-state lasers (such as YAG lasers) are preferably used in terms of practicality such as maintainability and price. The recording wavelength of these lasers is in the infrared wavelength region, and an oscillation wavelength of 800 nm to 1100 nm is often used. Exposure can also be performed using an imaging device described in JP-A-6-186750.

When a film for protecting the surface of the silicone rubber layer is provided as described above, when the film is exposed to laser light, the film may be exposed as it is if it is a light-transmitting film, or the film may be peeled off. Exposure may be performed later. Exposure with such an infrared laser reduces the adhesion between the support and the silicone rubber layer due to the reaction of the light-to-heat conversion layer in the exposed portion, and the ink repellent layer in the exposed portion is removed in the subsequent development step. Thus, an image area is formed as a parent ink area, and the silicone rubber layer in an unexposed area becomes a non-image area as an ink repellent area, thereby obtaining a lithographic printing plate requiring no dampening solution.

As the developer used for making the waterless lithographic printing plate precursor of the present invention, those known as developers for waterless lithographic printing plate precursors, for example, hydrocarbons, polar solvents, water and Can be appropriately selected from combinations and the like. However, from the viewpoint of safety, it is preferable to use water or an aqueous solution of an organic solvent containing water as a main component. The concentration of the solvent is desirably less than 40% by weight.

Examples of the hydrocarbons that can be used in the developer include aliphatic hydrocarbons [specifically, for example, hexane, heptane, gasoline, kerosene, commercially available solvents such as “Isoper E, H, G” (Esso Chemical Co., Ltd.), aromatic hydrocarbons (eg, toluene, xylene, etc.), and halogenated hydrocarbons (trichlene, etc.). Also,
As the polar solvent, alcohols (specifically, for example, methanol, ethanol, propanol, isopropanol, benzyl alcohol, ethylene glycol monomethyl ether, 2-ethoxyethanol, diethylene glycol monoethyl ether, diethylene glycol monohexyl ether, triethylene glycol monomethyl Ether, propylene glycol monoethyl ether, dipropylene glycol monomethyl ether, polyethylene glycol monomethyl ether, polypropylene glycol, tetraethylene glycol, etc.), ketones (eg, acetone, methyl ethyl ketone, etc.), esters (eg, ethyl acetate, methyl lactate, Butyl lactate, propylene glycol monomethyl ether acetate, diethylene glycol Lumpur acetate, diethyl phthalate), other, triethyl phosphate, tricresyl phosphate and the like. Also, simply tap water,
Water itself such as pure water or distilled water can also be used. These may be used alone, and for example, water may be added to hydrocarbons, water may be added to a polar solvent, or a combination of a hydrocarbon and a polar solvent may be used in combination of two or more. .

Further, in preparing the developing solution, if a hydrocarbon or a polar solvent having a low affinity for water is used, a surfactant or the like may be added to improve the solubility in water. . In addition, an alkali agent (for example, sodium carbonate, diethanolamine, sodium hydroxide, etc.) can be added together with the surfactant.

The development can be carried out by a known method, for example, by rubbing the plate surface with a developing pad containing the above-mentioned developer, or by pouring the developer onto the plate and rubbing it with a developing brush in water. it can. The developer temperature can be any temperature, but is preferably from 10C to 50C. As a result, the silicone rubber layer, which is the ink repellent layer in the image area, is removed, and that area becomes the ink receiving area. The development processing described above, or the subsequent washing and drying processing, can also be performed by an automatic processor. A preferable example of such an automatic processor is described in JP-A-2-22661.

Further, the waterless planographic printing plate precursor of the present invention can be developed by bonding the adhesive layer to the surface of the silicone rubber layer and then peeling off the adhesive layer. Any known adhesive layer that can be in close contact with the surface of the silicone rubber layer can be used. The adhesive layer provided on a flexible support is commercially available, for example, under the trade name of "Scotch Tape # 851A" manufactured by Sumitomo 3M Limited. When the waterless planographic printing plates thus treated are stacked and stored, it is preferable to insert and sandwich a slip sheet to protect the waterless planographic printing plates.

The lithographic printing plate without water according to the present invention thus obtained is set in a predetermined printing machine,
Printing is performed by supplying ink. The waterless planographic printing plate (original plate) of the present invention has good storage stability, so that even after storage for a long period of time after production, there are no deterioration such as delamination or decrease in sensitivity, and a large number of good printed matter can be obtained. be able to.

[0131]

EXAMPLES The present invention will be described in more detail with reference to Synthesis Examples, Examples and Comparative Examples, which should not be construed as limiting the invention thereto.

[Synthesis Example] (Synthesis Example 1: Polyurethane resin 1) In a 1000 ml three-necked round bottom flask equipped with a condenser and a stirrer,
2,2-bis (hydroxymethyl) propionic acid30.
0 g (0.224 mol), and 24.9 g (0.02 g) of polypropylene glycol (weight average molecular weight 1000).
(5 mol) was dissolved in 340 g of N, N-dimethylacetamide to prepare a solution. Next, 65.2 g (0.260 mol) of 4,4′-diphenylmethane diisocyanate was added, and the mixture was heated and stirred at 60 ° C. for 2 hours. Subsequently, 2 g of ethylene glycol monoallyl ether was added, and a further 6 g were added.
Heating and stirring were continued at 0 ° C. for 1 hour. Thereafter, 200 ml of N, N-dimethylacetamide and 40 parts of methyl alcohol
It was diluted with 0 ml. The reaction solution was poured into water 41 with stirring to precipitate a white polymer. The polymer is separated by filtration, washed with water and dried under vacuum to give 1
20 g of a white polymer (polyurethane resin 1) was obtained. Gel permeation chromatography (GP
When the molecular weight was measured in C), it was 80,000 in weight average (polystyrene standard).

(Synthesis Example 2: Polyurethane resin 2) Using the same apparatus as in Example 1, 12.1 g (0.09 mol) of 2,2-bis (hydroxymethyl) propionic acid and a polyester diol compound ( Sun Ester 246
20; Sanyo Kasei Co., Ltd.) (20.0 g, 0.01 mol) was dissolved in N, N-dimethylacetamide (100 g) to prepare a solution. Next, 25.8 g (0.103 mol) of 4,4′-diphenylmethane diisocyanate was added, and the mixture was heated and stirred at 100 ° C. for 5 hours. Subsequently, 1 g of ethylene glycol monoallyl ether was added, and a further 10 g.
Heating and stirring were continued at 0 ° C. for 1 hour. Thereafter, the same post-treatment as in Synthesis Example 1 was performed to obtain 50 g of a white polymer (polyurethane resin 2). The molecular weight was measured by gel permeation chromatography (GPC) and found to be 50,000 in weight average (polystyrene standard).

(Comparative Synthesis Example 1: Polyurethane resin 3) In a 1000 ml three-neck round bottom flask equipped with a condenser and a stirrer, 30.0 g (0.224 mol) of 2,2-bis (hydroxymethyl) propionic acid was added. )) And polypropylene glycol (weight average molecular weight 1000)
9 g (0.025 mol) was dissolved in 340 g of N, N-dimethylacetamide to prepare a solution. Next, 4,4 '
65.2 g of diphenylmethane diisocyanate (0.
260 mol), and the mixture was heated and stirred at 60 ° C. for 2 hours. Then, 200 ml of N, N-dimethylacetamide
And 400 ml of methyl alcohol. The reaction solution was poured into water 41 with stirring to precipitate a white polymer. The polymer was separated by filtration, washed with water, and dried under vacuum to obtain 120 g of a white polymer (polyurethane resin 3). The molecular weight was measured by gel permeation chromatography (GPC) and found to be 80,000 in weight average (polystyrene standard).

(Examples 1 and 2, Comparative Example 1) [Formation of light-to-heat conversion layer] The following mixed solution was stirred with glass beads for 30 minutes in a paint shaker to disperse carbon black, and the glass beads were filtered off. Then, 0.2 parts by weight of a fluorine-based surfactant Megafac F177 (manufactured by Dainippon Ink and Chemicals, Inc.) was added and stirred to prepare a light-heat conversion layer coating solution. This coating solution was applied on a corona-treated transparent polyethylene terephthalate film having a thickness of 188 μm so as to have a dry film thickness of 1 μm, and dried by heating to form a photothermal conversion layer.

-75 parts by weight of the polyurethane resin described in Table 1-25 parts by weight of carbon black (# 40 manufactured by Mitsubishi Carbon Co., Ltd.)-2 parts by weight of Solsperse S27000 (manufactured by ICI)-1000 parts by weight of propylene glycol monomethyl ether

[0137]

[Table 1]

[Formation of Silicone Rubber Layer] The following coating solution was applied on the photothermal exchange layer, and heated (130 ° C., 1
Min) and dried to form an addition type silicone rubber layer having a dry film thickness of 2 μm. 9 parts by weight of α, ω-divinylpolydimethylsiloxane (degree of polymerization 500) 0.2 parts by weight of (CH ₃ ) ₃ SiO (SiH (CH ₃ ) O) ₈ —Si (CH ₃ ) ₃・ Olefin-platinum chloride 0.15 parts by weight of acid ・ Control agent [HC≡CC (CH ₃ ) ₂ —O—Si (CH ₃ ) ₃ ] 0.2 part by weight ・ Isopar G (manufactured by Esso Chemical Co., Ltd.) 120 parts by weight

A 12 μm polyethylene terephthalate was laminated on the surface of the silicone rubber layer obtained as described above to obtain a waterless planographic printing plate precursor covered with the cover films of Examples 1 and 2 and Comparative Example 1. .

[Measurement of Sensitivity] After the cover films of the obtained waterless planographic printing plate precursors of Examples 1 and 2 and Comparative Example 1 were peeled off, the wavelength was 830 nm and the beam diameter was 32 μm (1/1).
e ^2), by using a semiconductor laser of output 300 mW, it has been written in continuous line by changing the writing speed. Thereafter, the plate surface was wiped with a developing pad containing isopropanol to remove the silicone rubber layer in the laser-irradiated portion, and the plate surface energy capable of removing the silicone rubber layer in the irradiated portion as a continuous line was determined as sensitivity. The measurement results are also shown in Table 1 above.

[Evaluation of Storage Stability] Obtained Examples 1 to
2. Each of the waterless planographic printing plate precursors of Comparative Example 1 was heated to a temperature of 45
Exposure to an environment of 75 ° C. and a humidity of 75% for 7 days, the same treatment as in the measurement of the sensitivity was performed, and the state of the silicone rubber layer was visually observed. , And those in which peeling was observed were evaluated as x. The evaluation results are also shown in Table 1 above.

From the results shown in Table 1, the waterless planographic printing plate precursor using (A) the specific polyurethane resin having a carboxyl group and an ethylenically unsaturated bond group (polymerizable or crosslinkable functional group) for the light-to-heat conversion layer is as follows: It became clear that the storage stability was high and the sensitivity was high. On the other hand, it was found that a waterless planographic printing plate precursor using a polyurethane resin having no ethylenically unsaturated bonding group for the light-to-heat conversion layer, although having high sensitivity, had low storage stability and was problematic in practical use.

[0143]

EFFECT OF THE INVENTION The lithographic printing plate precursor requiring no dampening solution (lithographic printing plate precursor without water) of the present invention has good storage stability and high sensitivity when recording images with a heat mode laser. It has an excellent effect that no harmful substances are generated. Further, by exposing and developing the lithographic printing plate precursor requiring no dampening solution of the present invention, a lithographic printing plate requiring no dampening solution can be easily obtained.

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2H025 AA01 AA11 AB04 AC08 AD01 BC13 BC66 BC85 CC11 DA31 DA37 FA10 2H096 AA13 BA06 EA04 EA23 2H114 AA05 AA14 AA22 AA24 BA01 BA10 DA03 DA46 DA60 EA01 EA02 FA16

Claims (2)

[Claims] 1. A fountain solution-free lithographic printing plate precursor comprising a support, on which a photothermal conversion layer for converting laser light into heat and a silicone rubber layer are laminated in this order, wherein the photothermal conversion layer comprises A fountain solution-free lithographic printing plate precursor comprising: a light-to-heat conversion agent; and a polyurethane resin having at least one carboxyl group and having a polymerizable or crosslinkable functional group. 2. The lithographic printing plate precursor requiring no dampening solution according to claim 1, wherein the polymerizable or crosslinkable functional group is an ethylenically unsaturated bond group.