JPH11216964A - Laser direct drawing type lithographic printing plate material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a laser direct drawing type lithographic printing plate material which has a high sensitivity, and is excellent in preservation stability, and also, excellent in printing property by a method wherein an alkali soluble binder, a substance which reduces the alkali solubility of this binder, and an infrared ray absorbing dye which does not reduce the alkali solubility, are used. SOLUTION: A positive type lithographic printing plate material by which a direct plate making is possible, is manufactured by containing an alkali soluble binder, a substance which substantially reduces the alkali solubility of the binder, and an infrared ray absorbing dye which does not substantially reduce the alkali solubility of the binder. As the infrared ray absorbing dye which does not substantially reduce the alkali solubility of the binder, one having a salt structure wherein the existing location of a coupled ion is limited in the same molecule, is preferable. In addition, an infrared ray absorbing dye which substantially reduces the alkali solubility of the binder may be contained. By this method, the range of an amount which can be added of the infrared ray absorbing dye is expanded, and a laser direct drawing lithographic printing plate material of a high sensitivity is provided.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image recording material which can be used as a lithographic printing plate material, and more particularly to a so-called direct lithographic, positive type lithographic plate which can directly make a plate by using an infrared laser from a digital signal of a computer or the like. Related to printing plate materials.

[0002]

2. Description of the Related Art Lasers have been remarkably developed in recent years. In particular, solid-state lasers and semiconductor lasers which emit infrared rays having a wavelength of 760 nm to 1200 nm have become easily available in high power and small size. These lasers are very useful as a recording light source when directly making a plate from digital data of a computer or the like.
Laser plate making machines using a semiconductor laser that emits light in the vicinity and a YAG laser that emits light at 1064 nm are on the market. However, many photosensitive recording materials that are practically useful have a photosensitive wavelength in the visible light range of 760 nm or less.
Images cannot be recorded with these infrared lasers. Therefore, a material that can be recorded by an infrared laser is desired.

As a recording material recordable with such an infrared laser, a heat-sensitive recording material containing a resol type phenol resin and carbon black disclosed in JP-A-56-69193 and JP-A-7-20629 are disclosed. And a recording material comprising an onium salt, a resol resin, a novolak resin, and an infrared absorber. Also,
JP-A-7-271029 describes a recording material comprising a haloalkyl-substituted s-triazine, a resole resin, a novolak resin, and an infrared absorber. However, these recording materials are not sufficient from the viewpoints of sensitivity, storage stability and printability, and further improvement has been desired.

In a lithographic printing plate material, an infrared absorbing dye requires a certain amount of addition in order to increase the sensitivity to laser. On the other hand, if the infrared absorbing dye is added too much, the sensitivity may be lowered or printing smear may be caused, and it is necessary to adjust the addition amount to the optimum value. In some cases, it was not possible to find a suitable addition amount region.

[0005]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to make a plate directly from digital data of a computer or the like by recording using a solid-state laser and a semiconductor laser that emit infrared light, to provide high sensitivity, An object of the present invention is to provide a laser direct-writing type lithographic printing plate material having excellent storage stability and excellent printability.

[0006]

The above objects have been achieved by the present invention as a result of intensive studies. That is, the present invention is characterized by comprising (1) an alkali-soluble binder, a substance that substantially reduces the alkali solubility of the binder, and an infrared absorbing dye that does not substantially lower the alkali solubility of the binder. It is a laser direct drawing type planographic printing plate material. (2) The laser direct-writing type according to (1), wherein the infrared-absorbing dye that does not substantially reduce the alkali solubility of the binder has a salt structure in which the counter ion is located in the same molecule. It is a lithographic printing plate material. (3) The lithographic printing plate material according to (1) or (2), further comprising an infrared absorbing dye which substantially reduces the alkali solubility of the binder.

As a result of intensive studies, the present inventors have found that a decrease in sensitivity due to excessive addition of an infrared absorbing dye occurs when the infrared absorbing dye itself has an action of substantially reducing the alkali solubility of a binder. This has led to the completion of the present invention. That is, by using an infrared-absorbing dye that does not substantially reduce the alkali solubility of the binder, the range of the amount in which the infrared-absorbing dye can be added is widened, and a highly sensitive laser direct-drawing lithographic printing plate material can be obtained.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail.
First, an infrared absorbing dye that does not substantially reduce the alkali solubility of the binder used in the present invention will be described.

[Infrared absorbing dye which does not substantially reduce alkali solubility of binder] The infrared absorbing dye which does not substantially reduce alkali solubility of the binder used in the present invention is a laser direct drawing type lithographic printing plate using the same. When a material (hereinafter sometimes simply referred to as a "lithographic printing plate material") is prepared, the alkali solubility of an alkali-soluble binder used at the same time is not reduced, or even if it is slightly reduced, the lithographic printing plate material is used. An infrared absorbing dye capable of maintaining sufficient alkali solubility as a binder required for a printing plate material.

Whether or not the infrared absorbing dye has the property of substantially reducing the alkali solubility of the alkali-soluble binder can be determined by measuring a specific alkali-soluble binder as a representative. Therefore, in the present invention, the presence or absence of the property is determined based on the following determination index.

"Indicator for judging whether infrared absorbing dye has property of substantially reducing alkali solubility of alkali-soluble binder" A test coating solution having the composition shown below is prepared.

(Composition of test coating solution) ・ Alkali-soluble binder (Novolak resin obtained from cresol and formaldehyde (meta: para ratio = 6: 4, weight average molecular weight 1,800) 2.00 g ・ Infrared to be measured Absorptive dye 0.20 g ・ Methyl ethyl ketone 20 g ・ Methyl alcohol 7 g

The test coating solution is applied to a polyester film and dried to obtain a test film X. Further, a control coating solution from which the infrared absorbing dye was removed from the test coating solution was prepared, applied to a polyester film in the same manner, and dried to obtain a control film B. About this test film X, the absorption amount of UV light (400 nm) was measured (X1). Further, the test film X and the control film B are immersed in a developer A having the following composition for 30 seconds.

(Composition of Developer A) 99.8% by weight of an aqueous solution of sodium silicate containing 2.0% by weight of SiO ₂ at a molar ratio of [SiO ₂ ] / [K ₂ O] of 0.98. Diethylene triamine penta (methylene) Phosphonic acid) 5Na salt 0.2% by weight

After the test film X and the control film B immersed in the developing solution A are washed with water and dried, the absorption amounts of UV light (400 nm) are measured respectively (X2 and B).
2). At this time, since the control film B contains no infrared absorber, almost all of the film of the test coating solution on the surface is removed by the developer A showing alkalinity due to the alkali solubility inherent in the alkali-soluble binder. On the other hand, the test film X containing the infrared absorbing agent may be partially affected by the infrared absorbing agent, with a part of the surface of the test coating liquid remaining on the surface. The residual ratio (%) of the test coating solution is the residual ratio (%) of the alkali-soluble binder, which can be seen from the change in the amount of absorption of UV light and can be expressed by the following equation.

[0016]

(Equation 1)

In the present invention, those having a residual ratio (%) exceeding 5% are regarded as having substantially reduced alkali solubility. Therefore, the term "infrared absorbing dye which does not substantially reduce the alkali solubility of the binder" in the present invention refers to a dye having a residual ratio of 5% or less obtained by the test of the above judgment index.

As the infrared absorbing dye which does not substantially reduce the alkali solubility of the binder, a salt structure in which the counter ion of the dye is located within the same molecule (hereinafter referred to as "intramolecular salt type") is preferable. Examples of the infrared absorbing dye that does not substantially reduce the alkali solubility of the binder include hesperidin squarylium dye, squarylium dye, croconium dye, neutral merocyanine dye, inner salt cyanine dye, and phthalocyanine dye. Hesperidin squarylium dye is preferred, and a compound represented by the following general formula (1) is particularly preferred. General formula (1)

[0019]

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In the general formula (1), R¹, R^Two, R^Three,
R^Four, R^Five, R⁶, R⁷, R⁸, R ⁹, R^Ten, R¹¹And
And R¹²Represents a hydrogen atom, an alkyl group,
Kill group, aryl group, aralkyl group, alkenyl group,
A alkynyl group or an acyl group;¹And R^Two, R^ThreeWhen
R^Four, R^FiveAnd R⁶, R⁷And R⁸, R⁹And R^Ten, R¹¹And R
¹², R^TwoAnd R^Three, R⁶And R⁷, And R^TenAnd R¹¹From
One or more of the selected combinations
They may combine to form a 5- or 6-membered ring. n is 0
Alternatively, it represents an integer of 1 to 6. X¹, X^TwoAnd X^ThreeIs
Each represents a hydrogen atom or a monovalent group, and m is an integer of 1 to 3
Represents

More specifically, in the general formula (1), the alkyl group represented by R ¹ to R ^{12 has 1} to 20 carbon atoms.
More preferably, they are 1-12 alkyl groups (for example, methyl, ethyl, propyl, butyl, hexyl, undecyl). Further, a halogen atom (for example, F, Cl,
Br), alkoxycarbonyl (eg, methoxycarbonyl, ethoxycarbonyl), hydroxy, alkoxy (eg, methoxy, ethoxy, phenoxy, isobutoxy), carboxyl, sulfo or acyloxy (eg, acetyloxy, butyryloxy, hexylyloxy, benzoyloxy) And so on. Examples of the cycloalkyl group represented by R ¹ to R ¹² include cyclopentyl, cyclohexyl, and the like, and may be substituted with the substituent described for the alkyl group.

The aryl group represented by R ¹ to R ¹² preferably has 6 to 12 carbon atoms, such as a phenyl group or a naphthyl group. Aryl groups may be substituted. Examples of the substituent include an alkyl group having 1 to 8 carbon atoms (for example, methyl, ethyl and butyl), an alkoxy group having 1 to 6 carbon atoms (for example, methoxy and ethoxy), and an aryloxy group (for example, phenoxy and p-chloro). Phenoxy), halogen atoms (eg, F, Cl,
Br), an alkoxycarbonyl group (for example, methoxycarbonyl, ethoxycarbonyl), a cyano group, a nitro group, a sulfo group, a carboxyl group, a hydroxy group, an amino group, an acylamino group (for example, acetylamino, propionylamino and the like) and an acyloxy group ( For example, acetyloxy, butyryloxy, etc.) are included.

The aralkyl group represented by R ¹ to R ¹² is preferably an aralkyl group having 7 to 12 carbon atoms (eg, benzyl, phenylethyl), and has a substituent (eg, a methyl, methoxy, chloro atom). It may be. R
¹ The alkenyl group represented by R ^12, 2-pentenyl, 2-butenyl, may be mentioned 1-propenyl and 2-propenyl. Examples of the alkynyl group represented by R ¹ to R ¹² include ethynyl and 2-propynyl. Examples of the acyl group represented by R ¹ to R ¹² include acetyl, propionyl, benzoyl, and the like, and may form a ring.
In the general formula (1), examples of the monovalent group represented by X ¹ , X ² and X ³ include the substituents described above for the aryl group.

In the general formula (1), n is 0 or 1
Represents an integer of from 6 to 6, and each compound may be used alone or in a mixture. In the case of a mixture, n is a mixture of 0 and 1, n is a mixture of 1 and 2, n is a mixture of 2 and 3, n is a mixture of 3 and 4, n is a mixture of 0, 1 and 2, n is Any combination such as a mixture of 1, 2, and 3, n is 0, 1, 2, and 3, and n is 0, 1, 2, 3, and 4 may be used.

Specific examples of the hesperidin squarylium dye (dihydroperimidine squarylium compound) preferably used in the present invention and represented by the above general formula (1) are shown below.

[0026]

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[0027]

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[0028]

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[0029]

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[0030]

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The following is an example of specific values of the residual ratio (%) obtained by the test of the above-mentioned "index for judging the presence or absence of the property of substantially reducing the alkali solubility of the alkali-soluble binder of the infrared absorbing dye". .

[0032]

[Table 1]

In the present invention, the dihydroperimidine squarylium compound represented by the general formula (1), which is suitably used, can be synthesized according to the following reaction formula. Further, n in the reaction formula can be adjusted by the charged amount of squaric acid.

[0034]

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In the present invention, the dihydroperimidine squarylium compound represented by the above general formula (1), which is suitably used, can be specifically synthesized as follows.

(Synthesis of Compound 1) 39.6 g of 1,8-diaminonaphthalene, 71.5 g of dipentylcarbonyloxymethyl ketone and 30 mg of sodium p-toluenesulfonate monohydrate were heated and stirred in a steam bath for 3 hours.
After adding 150 ml of methyl alcohol, the precipitated crystals were filtered and 2,2-dipentylcarbonyloxymethyl-2,
97.3 g of 3-dihydroperimidine (a) was obtained. 2.13 g of (a) obtained above, 0.57 g of squaric acid, n
A mixture of 10 ml of butyl alcohol and 10 ml of toluene at an external temperature of 130 ° C. while removing the water formed.
Heated for hours. 20 ml of methyl alcohol was added, and the precipitated crystals were separated by filtration. Thereafter, Compound 1 was fractionated by column chromatography using silica gel and chloroform (yield: 0.5 g, λ _max : 948.2 nm (acetone), ε: 2.19 × 10 ⁵ ).

(Synthesis of Compound 2) 17.5 g of (a) obtained in the above (Synthesis of Compound 1), squaric acid 2.1
g, n-butyl alcohol 100 ml and toluene 1
00 ml of the mixture at an external temperature of 1 while removing the water formed.
The mixture was heated and stirred at 30 ° C. for 3 hours. After allowing to cool, 50 ml of methyl alcohol was added, the crystals were filtered off, and the compound (c) was subjected to column chromatography using silica gel and chloroform.
I got 3.2 g of the compound (c) obtained above, 0.178 g of squaric acid, 30 ml of n-butyl alcohol and 30 ml of toluene were heated at an external temperature of 140 ° C. 30 ml of acetone was added, and the precipitated crystals were separated by filtration and then recrystallized from methylene chloride-acetone to give Compound 2 as 8.
9 g (yield: 0.55 g, λ _max : 1070.5 n)
m (CH ₂ Cl ₂ ), ε: 1.69 × 10 ⁵ ).

(Synthesis of Compound 9) 84.5 g of 2-methyl-2-undecyl-2,3-dihydroperimidine, 22.3 g of squaric acid, 500 ml of n-butyl alcohol
And 500 ml of toluene was heated and stirred at an external temperature of 140 ° C. for 4 hours. The precipitated crystals were separated by filtration and washed with acetone to obtain 50 g of Compound 9. λ _max : 810 nm (1.0), 991.6 nm (1.
25), 1120.4 nm (1.36), 1200 nm
(0.9), solvent = CH ₂ Cl _2. The numerical value in parentheses is ε, and is shown as a relative value when the absorbance at n = 0 is 1.

In the present invention, the dihydroperimidine squarylium compound represented by the general formula (2), which is suitably used, can be specifically synthesized as follows.

(Synthesis of Compound 26) 17.5 of 2,2-dipentylcarbonyloxymethyl-2,3-dihydroperimidine (a) obtained in the synthesis of Compound 1 described above.
g, squaric acid 2.1 g, n-butyl alcohol 10
A mixture of 0 ml and 100 ml of toluene was heated and stirred at an external temperature of 130 ° C. for 3 hours while removing generated water.
After cooling, 50 ml of methyl alcohol was added, and the precipitated crystals were separated by filtration. Thereafter, compound 26 was obtained by column chromatography using silica gel and chloroform (yield: 10.9 g, λ _max : 796 nm (CH ₂ C
l ₂ ), ε: 1.2 × 10 ⁵ ).

[0041]

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Dihydroperimidine squarylium compounds other than those mentioned in the above synthesis examples can be synthesized in the same manner. Table 2 shows λ _max of the synthesized dihydroperimidine squarylium compound.

[0043]

[Table 2]

[Infrared absorbing dye which substantially reduces alkali solubility] In the present invention, an infrared absorbing dye which substantially lowers alkali solubility can be used together with the infrared absorbing dye which does not substantially lower alkali solubility. Good. The index of whether or not alkali solubility is substantially reduced is the same as that of the "infrared absorbing dye which does not substantially reduce alkali solubility". That is, in the test of the above-mentioned judgment index, those having a residual ratio (%) of more than 5% are referred to as infrared absorbing dyes that substantially reduce alkali solubility in the present invention. Examples of the infrared absorbing dye that substantially reduces alkali solubility include a cyanine dye, an aminium dye, and a diimmonium dye. Examples of the cyanine dye include those represented by the following general formula (2).

[0045]

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In the general formula (2), R _{1 to} R ₄ each independently represent a hydrogen atom or a C _{1 to} C ₄ which may have a substituent.
12 represents an alkyl group, an alkenyl group, an alkoxy group, a cycloalkyl group, or an aryl group, and R ₁ and R ₂ , and R ₃ and R ₄ may be bonded to each other to form a ring structure.
Here, as R _{1 to} R ₄ , specifically, a hydrogen atom,
Examples include a methyl group, an ethyl group, a phenyl group, a dodecyl group, a naphthyl group, a vinyl group, an allyl group, and a cyclohexyl group. When these groups have a substituent, examples of the substituent include a halogen atom, a carbonyl group, a nitro group, a nitrile group, a sulfonyl group, a carboxyl group, a carboxylic acid ester, and a sulfonic acid ester.
R _{5 to} R ₁₀ each independently represent an alkyl group having 1 to 12 carbon atoms which may have a substituent, wherein R _{5 to} R ₁₀
Specific examples include a methyl group, an ethyl group, a phenyl group, a dodecyl group, a naphthyl group, a vinyl group, an allyl group, and a cyclohexyl group. When these groups have a substituent, examples of the substituent include a halogen atom, a carbonyl group, a nitro group, a nitrile group, a sulfonyl group, a carboxyl group, a carboxylic acid ester, and a sulfonic acid ester.

R _{11 to} R ₁₃ each independently represent a hydrogen atom,
Represents a halogen atom or an alkyl group having 1 to 8 carbon atoms which may have a substituent, wherein R ₁₂ may be bonded to R ₁₁ or R ₁₃ to form a ring structure, and m> In the case of 2, a plurality of R ₁₂ may be bonded to each other to form a ring structure.
As R _{11 to} R ₁₃ , specifically, a chlorine atom, a cyclohexyl group, a cyclopentyl ring in which R ₁₂ is bonded to each other,
And a cyclohexyl ring. When these groups have a substituent, examples of the substituent include a halogen atom, a carbonyl group, a nitro group, a nitrile group, a sulfonyl group, a carboxyl group, a carboxylic acid ester, and a sulfonic acid ester. M represents an integer of 1 to 8, and preferably 1 to 3. R _{14 to} R ₁₅ each independently represent a hydrogen atom, a halogen atom, or an alkyl group having 1 to 8 carbon atoms which may have a substituent, and R ₁₄ is bonded to R ₁₅ to form a ring structure. When m> 2, a plurality of R ₁₄ may be bonded to each other to form a ring structure. R
Specific examples of _{14 to} R ₁₅ include a chlorine atom, a cyclohexyl group, a cyclopentyl ring and a cyclohexyl ring formed by bonding R _{14 to} each other. When these groups have a substituent, the substituent may be a halogen atom,
Carbonyl group, nitro group, nitrile group, sulfonyl group,
Examples thereof include a carboxyl group, a carboxylic acid ester, and a sulfonic acid ester. M represents an integer of 1 to 8,
Preferably it is 1-3.

[0048] In the general formula (2), X ^- Specific examples of the anion is represented by, perchloric acid, tetrafluoroboric acid, hexafluorophosphoric acid, triisopropyl naphthalenesulfonic acid, 5-nitro -o -Toluenesulfonic acid, 5-sulfosalicylic acid, 2,5-dimethylbenzenesulfonic acid, 2,4,6-trimethylbenzenesulfonic acid, 2-
Nitrobenzenesulfonic acid, 3-chlorobenzenesulfonic acid, 3-bromobenzenesulfonic acid, 2-fluorocaprylnaphthalenesulfonic acid, dodecylbenzenesulfonic acid, 1-naphthol-5-sulfonic acid, 2-methoxy-4-hydroxy-5-benzoyl -Benzenesulfonic acid and paratoluenesulfonic acid. Among them, alkyl aromatic sulfonic acids such as hexafluorophosphoric acid, triisopropylnaphthalenesulfonic acid and 2,5-dimethylbenzenesulfonic acid are particularly preferable.

Specific examples of the compound represented by the general formula (2) are shown below, but the present invention is not limited to these specific examples.

[0050]

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Aminium dyes and diimmonium dyes which can be used as the infrared absorbing dye which substantially reduces alkali solubility include dyes (compounds) represented by the following general formulas (3) and (4).

[0052]

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In the above formula, A is

[0054]

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(K represents 1 or 2), and B
Is

[0056]

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(K represents 1 or 2), and the aromatic ring may be substituted with a lower alkyl group, a lower alkoxy group, a halogen atom or a hydroxyl group. R ₂₁
To R ₂₈ are each independently a hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted alkynyl group, R ₂₁ And R ₂₂ ,
R ₂₃ and R ₂₄ , R ₂₅ and R ₂₆ or R ₂₇ and R ₂₈ together with N form a substituted or unsubstituted 5-membered ring, substituted or unsubstituted 6-membered ring, substituted or unsubstituted 7-membered ring. May be. X ⁻ represents an anion as in the general formula (29).

The compound represented by the general formula (3) or (4) is a known compound, for example, US Pat.
No. 75871 and U.S. Pat. No. 3,557,012.

Other commercially available products which can be used for infrared absorbing dyes which substantially reduce alkali solubility include Epolite IV-62B, Epolite III-178,
Epolite III-130 (from Eporin), IR
G-022, IRG-002, IRG-003 (above,
Manufactured by Nippon Kayaku Co., Ltd.).

[Alkali-Soluble Binder] Examples of the alkali-soluble binder used in the present invention include novolak resin, polyhydroxystyrene, and acrylic resin. The novolak resin used in the present invention is a resin obtained by condensing phenols and aldehydes under acidic conditions. Preferred novolak resins include, for example, a novolak resin obtained from phenol and formaldehyde, a novolak resin obtained from m-cresol and formaldehyde, a novolak resin obtained from p-cresol and formaldehyde, a novolak resin obtained from o-cresol and formaldehyde, Novolak resin obtained from octylphenol and formaldehyde, novolak resin obtained from m- / p-mixed cresol and formaldehyde, phenol /
Cresol (o-, m-, p- or m- / p-, m- /
o- or o- / p-mixture) and a novolak resin obtained from formaldehyde. These novolak resins have a weight average molecular weight of 8
With a number average molecular weight of 400-6
000 is preferred.

Examples of the alkali-soluble binder other than the novolak resin used in the present invention include polyhydroxystyrenes, hydroxystyrene-N-substituted maleimide copolymers, hydroxystyrene-maleic anhydride copolymers, and alkali-soluble groups. Acrylic polymer having the same, a urethane type polymer having an alkali-soluble group, and the like. Here, examples of the alkali-soluble group include a carboxyl group, a phenolic hydroxyl group, a sulfonic acid group, a phosphonic acid group, and an imide group.

Further, hydroxystyrene-based polymers such as poly-p-hydroxystyrene, poly-m-hydroxystyrene, p-hydroxystyrene-N-substituted maleimide copolymer and p-hydroxystyrene-maleic anhydride copolymer are used. When used, the weight average molecular weight is 2,000
~ 500,000, and 4,000 ~ 300,00
0 is preferred.

Examples of the acrylic polymer having an alkali-soluble group include methacrylic acid-benzyl methacrylate copolymer, poly (hydroxyphenyl methacrylamide), poly (hydroxyphenylcarbonyloxyethyl acrylate), poly (2,4-dihydroxy Phenylcarbonyloxyethyl acrylate), and the polymers described in Japanese Patent Application No. Hei 8-211731. These acrylic polymers have a weight average molecular weight of 2,000 to 500,000, preferably 4,000 to 500,000.
300,000 are preferred.

Examples of urethane-type polymers having an alkali-soluble group include resins obtained by reacting diphenylmethane diisocyanate with hexamethylene diisocyanate, tetraethylene glycol, and 2,2-bis (hydroxymethyl) propionic acid. Among these alkali-soluble polymers, a hydroxystyrene-based polymer and an acrylic copolymer having an alkali-soluble group are preferred from the viewpoint of developability.

In the present invention, these alkali-soluble binders are used in an amount of 10 to 90% by weight, preferably 20 to 85% by weight, particularly preferably 3 to 90% by weight, based on the total solid content of the lithographic printing plate material.
It is used in an amount of 0 to 80% by weight. If the amount of the alkali-soluble polymer compound is less than 10% by weight, the durability of the recording layer is deteriorated, and if it exceeds 90% by weight, it is not preferable in terms of both sensitivity and durability. These alkali-soluble binders may be used alone or in combination of two or more.

[Substance that Substantially Reduces Alkali-Soluble of Binder] In the present invention, the substance that substantially reduces the alkali-solubility of the alkali-soluble binder by the heat generated by the infrared absorber absorbing infrared rays is used. The effect disappears and a positive image is formed. Only by this function of this substance can an image be formed on the lithographic printing plate material of the present invention. As the index for determining whether or not the alkali solubility in this substance is substantially reduced, the same determination index as in the case of the above-mentioned infrared absorbent is used.

Specific examples of substances which substantially reduce the alkali solubility of the binder include, for example, SISchlesin
ger, Photogr. Sci. Eng., 18,387 (1974), TSBal et
al., Polymer, 21,423 (1980), etc., U.S. Pat.Nos. 4,069,055 and 4,069,056,
Ammonium salts described in 3-140, 140, etc., DCNeckeret
al., Macromolecules, 17,2468 (1984), CSWen et a
l., Teh, Proc. Conf.Rad. Curing ASIA, p478, Tokyo,
Oct (1988), U.S. Pat.Nos. 4,069,055 and 4,069,056
No., etc., JVCrivello et al., M
acromolecules, 10 (6), 1307 (1977), Chem. & Eng. New
s, Nov. 28, p31 (1988), European Patent No. 104,143, U.S. Patent Nos. 339,049 and 410,201, JP-A-2-150,848
Iodonium salts described in JP-A-2-296,514 and the like.
V. Crivello et al., Polymer J. 17, 73 (1985), JVCri
vello et al., J. Org.Chem., 43, 3055 (1978), WRWat
tet al., J. Polymer Sci., Polymer Chem. Ed., 22, 17
89 (1984), JVCrivello et al., Polymer Bull., 14, 27
9 (1985), JVCrivello et al., Macromolecules, 14
(5), 1141 (1981), JVCrivello et al., J. Polymer Sc
i., Polymer Chem.Ed., 17,2877 (1979), European Patent No. 37
0,693, U.S. Patent 3,902,114, European Patent 233,56
No. 7, 297,443, 297,442, U.S. Pat.
No. 377, No. 410,201, No. 339,049, No. 4,760,013
Nos. 4,734,444, 2,833,827, German Patent 2,90
Nos. 4,626, 3,604,580 and 3,604,581, sulfonium salts described in JVCrivello et al., Macromolecule
s, 10 (6), 1307 (1977), JVCrivello et al., J. Polym
er Sci., Polymer Chem.Ed., 17,1047 (1979), etc., and CSWen et al., Teh, Proc. Conf.
Onium salts such as arsonium salts described in Rad. Curing ASIA, p478, Tokyo, Oct (1988), etc.

US Pat. No. 3,905,815, JP-B-46-4605
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JP-A-62-58241, JP-A-62-212401, JP-A-63-702
No. 43, organic halogen compounds described in JP-A-63-298339, etc., K. Meier et al., J. Rad.Curing, 13 (4), 26 (198
6), TPGill et al., Inorg. Chem., 19,3007 (1980),
D. Astruc, Acc. Chem. Res., 19 (12), 377 (1896), organometallics / organic halides described in JP-A-2-14145 and the like,
S. Hayase et al., J. Polymer Sci., 25, 753 (1987), E.
Reichman et al., J. Polymer Sci., Poliymer Chem. E
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et al., J. Imaging Technol., 11 (4), (1985), HMH
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(1972), S. Hayase et al., Macromolecules, 18,1799 (1
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0,750, 046,083, 156,535, 271,851
No. 0,388,343, U.S. Pat.Nos. 3,901,710, 4,18
No. 1,531, JP-A-60-198538, JP-A-53-133022, etc., a photoacid generator having a 0-nitrobenzyl-type protecting group, TUNOOKA et al., Polymer Preprints Japan, 35
(8), G. Berner et al., J. Rad. Curing, 13 (4), WJM
ijs et al., Coating Technol., 55 (697), 45 (1983), A
kzo, H. Adachi et al., Polymer Preprints, Japan, 37
(3), European Patent Nos. 0199,672, 84515, and 199,672
No. 044,115, No. 0101,122, U.S. Pat.No. 4,618,55
No. 4, No. 4,371,605, No. 4,431,774, JP-A-64-181
No. 43, compounds disclosed in JP-A-2-245756, JP-A-3-140109, etc., which generate sulfonic acid by photolysis, such as iminosulfonates, and disulfones described in JP-A-61-166544. Compounds can be mentioned.

Compounds obtained by introducing these substances such as an acid generator into the main chain or side chain of a polymer, for example, MEWood
house et al., J. Am. Chem. Soc., 104, 5586 (1982),
SPPappas et al., J. Imaging Sci., 30 (5), 218 (198
6), S. Kondo et al., Makromol. Chem. Rapid Commu
n., 9,625 (1988), Y.Yamada et al., Makromol, Chem.
152, 153, 163 (1972), JVCrivello et al., J. Polyme
r Sci., Polymer Chem.Ed., 17,3845 (1979), U.S. Pat.No. 3,849,137, German Patent 3914407, JP-A-63-26653
No., JP-A-55-164824, JP-A-62-69263, JP-A-63
-14603, JP-A-63-163452, JP-A-62-153853,
The compounds described in JP-A-63-146029 can be used. Furthermore, VNRPillai, Synthesis, (1), 1 (198
0), A. Abad et al., Tetrahedron Lett., (47) 4555 (19
71), DHRBarton et al., J. Chem. Soc., (C), 329
(1970), U.S. Pat.No. 3,779,778, European Patent 126,712
Compounds that generate an acid by the light described in the above item can also be used.

Among the above-mentioned compounds, the compounds which are used particularly effectively are shown below. (1) The following general formula (PAG) substituted with a trihalomethyl group
The oxazole derivative represented by 1) or the general formula (PAG)
An s-triazine derivative represented by 2).

[0071]

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In the formula, R ¹ represents a substituted or unsubstituted aryl group or alkenyl group, R ² represents a substituted or substituted aryl group, alkenyl group or alkyl group, or —CY ₃ . Y represents a chlorine atom or a bromine atom. Specific examples include the following compounds, but the present invention is not limited thereto.

[0073]

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[0074]

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(2) An iodonium salt represented by the following formula (PAG3) or a sulfonium salt represented by the following formula (PAG4).

[0076]

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In the formula, Ar ¹ and Ar ² each independently represent a substituted or unsubstituted aryl group. Preferred substituents include an alkyl group, a haloalkyl group, a cycloalkyl group,
Aryl group, alkoxy group, nitro group, carboxy group,
Examples include an alkoxycarbonyl group, a hydroxy group, a mercapto group, and a halogen atom. R ³ , R ⁴ and R ⁵ each independently represent a substituted or unsubstituted alkyl group or aryl group. Preferred are an aryl group having 6 to 14 carbon atoms, an alkyl group having 1 to 8 carbon atoms, and substituted derivatives thereof. Preferred substituents are an alkoxy group having 1 to 8 carbon atoms, an alkyl group having 1 to 8 carbon atoms, a nitro group, a carboxyl group, a hydroxy group and a halogen atom for the aryl group, and a substituent for the alkyl group. Carbon number 1
8 is an alkoxy group, a carboxyl group, or an alkoxycarbonyl group.

Z^-Represents a counter anion, for example, B
F_Four, AsF₆ ^-, PF₆ ^-, SbF₆ ^-, Si
F₆ ^2-, ClO_Four ^-, CF_ThreeSO_Three ^-Perfluoro such as
Alkanesulfonic acid anion, pentafluorobenzene
Sulfonic acid anion, naphthalene-1-sulfonic acid ani
Condensed polynuclear aromatic sulfonate anions such as on
Quinone sulfonate anion, 9,10-dimethoxyan
Toracene-2-sulfonic acid anion, containing sulfonic acid group
Dyes and the like can be mentioned, but are not limited to these
is not. Also, R^Three, R^FourAnd R^FiveTwo of them
Ar¹And Ar^TwoIs through each single bond or substituent
May be combined.

Specific examples include the following compounds, but are not limited thereto.

[0080]

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[0081]

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The above-mentioned onium salts represented by the general formula (PAG3) or (PAG4) are known, for example, JWKnap
czyk et al., J. Am. Chem. Soc., 91, 145 (1969), AL
Maycok et al., J. Org.Chem., 35, 2532, (1970), E. Go
ethas et al., Bull.Soc.Chem.Belg., 73,546, (196
4), HM Leicester, J. Ame.Chem. Soc., 51, 3587 (1
929), JVCrivello et al., J. Polym. Chem. Ed., 1
8,2677 (1980); U.S. Pat.Nos. 2,807,648 and 4,247,47
No. 3, JP-A-53-101,331 and the like. (3) Disulfone derivatives represented by the following general formula (PAG5) or iminosulfonate derivatives represented by the following general formula (PAG6).

[0083]

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In the formula, Ar^ThreeAnd Ar^FourAre replaced independently
Or an unsubstituted aryl group. R ⁶Is replaced or nothing
It represents a substituted alkyl group or an aryl group. A is replacement
Or unsubstituted alkylene group, alkenylene group or aryl
Represents a len group. Specific examples include the compounds shown below.
However, the present invention is not limited to these.

[0085]

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[0086]

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The amount of these compounds is usually 0.001 to 40% by weight based on the total solids of the lithographic printing plate material.
Is used in a range of preferably 0.01 to 20% by weight,
More preferably, it is used in the range of 0.1 to 5% by weight.

[Other Components] The lithographic printing plate material of the present invention may contain various compounds other than those described above, if necessary. For example, a dye having a large absorption in the visible light region can be used as a colorant for an image. Specifically, Oil Yellow # 101, Oil Yellow # 103, Oil Pink # 312, Oil Green BG, Oil Blue BOS, Oil Blue # 603, Oil Black BY,
Oil Black BS, Oil Black T-505 (all manufactured by Orient Chemical Industries, Ltd.), Victoria Pure Blue, Crystal Violet (CI42555), Methyl Violet (CI42535), Ethyl Violet, Rhodamine B (CI145170B), Malachite Green (CI42000) , Methylene blue (CI5
2015) or the dyes described in JP-A-62-293247. These dyes are preferably added because the image area and the non-image area can be easily distinguished after image formation. The addition amount is
0.01 to 10% by weight based on the total solid content of the lithographic printing plate material
Is the ratio of

Further, in the lithographic printing plate material according to the present invention, Japanese Patent Application Laid-Open Nos. 62-251740 and 3-208514 are used in order to widen the stability of processing under development conditions.
Non-ionic surfactants described in JP-A-59-121044, JP-A-4-13149.
An amphoteric surfactant such as that described in JP-A No. 2-211 can be added. Specific examples of the nonionic surfactant include sorbitan tristearate, sorbitan monopalmitate, sorbitan triolate, monoglyceride stearic acid, and polyoxyethylene nonyl phenyl ether. Specific examples of the surfactant include alkyl di (aminoethyl) glycine, alkyl polyaminoethyl glycine hydrochloride, 2-alkyl-N-carboxyethyl-N-hydroxyethylimidazolinium betaine and N-tetradecyl-N, N-betaine. Type (for example,
(Trade name: Amogen K, manufactured by Dai-ichi Kogyo Co., Ltd.). The proportion of the nonionic surfactant and the amphoteric surfactant in the lithographic printing plate material is 0.05 to 15% by weight.
And more preferably 0.1 to 5% by weight.

Further, a plasticizer may be added to the planographic printing plate material according to the present invention, if necessary, in order to impart flexibility to the coating film. For example, butyl phthalyl, polyethylene glycol, tributyl citrate, diethyl phthalate, dibutyl phthalate, dihexyl phthalate, dioctyl phthalate, tricresyl phosphate, tributyl phosphate, trioctyl phosphate, tetrahydrofurfuryl oleate, acrylic acid or Oligomers and polymers of methacrylic acid are used.

In addition to these, epoxy compounds, vinyl ethers, phenol compounds having a hydroxymethyl group and phenol compounds having an alkoxymethyl group described in Japanese Patent Application No. 7-18120 may be added.

The lithographic printing plate material according to the present invention can be usually produced by dissolving each of the above-mentioned components in a solvent and coating the solution on a suitable support. As the solvent used here, ethylene dichloride, cyclohexanone,
Methyl ethyl ketone, methanol, ethanol, propanol, ethylene glycol monomethyl ether, 1-
Methoxy-2-propanol, 2-methoxyethyl acetate, 1-methoxy-2-propyl acetate, dimethoxyethane, methyl lactate, ethyl lactate, N, N-dimethylacetamide, N, N-dimethylformamide, tetramethylurea, N- Examples thereof include, but are not limited to, methylpyrrolidone, dimethyl sulfoxide, sulfolane, γ-butyl lactone, toluene, water and the like. These solvents are used alone or as a mixture. The concentration of the above components (total solids including additives) in the solvent is preferably 1 to 50% by weight. The amount of coating (solid content) on the support obtained after coating and drying varies depending on the application, but generally 0.5 to 5.0 g / m ² is preferred for a lithographic printing plate material. As a method of applying, various methods can be used, for example,
Examples include bar coater coating, spin coating, spray coating, curtain coating, dip coating, air knife coating, blade coating, roll coating, and the like. As the coating amount decreases, the apparent sensitivity increases, but the film characteristics of the image recording film deteriorate.

In the lithographic printing plate material according to the present invention, a surfactant for improving coating properties, for example, a surfactant described in
A fluorine-based surfactant as described in JP-A-170950 can be added. The preferred amount is
It is 0.01 to 1% by weight, more preferably 0.05 to 0.5% by weight, based on the total solid content of the lithographic printing plate material.

The support used in the present invention is a dimensionally stable plate-like material such as paper, plastic (eg, polyethylene, polypropylene, polystyrene, etc.) laminated paper, metal plate ( For example, aluminum, zinc, copper, etc.), plastic film (for example, cellulose diacetate, cellulose triacetate, cellulose propionate, cellulose butyrate, cellulose acetate butyrate,
Cellulose nitrate, polyethylene terephthalate, polyethylene, polystyrene, polypropylene, polycarbonate, polyvinyl acetal, etc.), and paper or plastic films on which a metal as described above is laminated or vapor-deposited.

As the support of the present invention, a polyester film or an aluminum plate is preferable, and among them, an aluminum plate which has good dimensional stability and is relatively inexpensive is particularly preferable. Suitable aluminum plates are a pure aluminum plate and an alloy plate containing aluminum as a main component and containing a trace amount of a different element, and may be a plastic film on which aluminum is laminated or vapor-deposited. The foreign elements contained in aluminum alloys include silicon, iron, manganese,
Copper, magnesium, chromium, zinc, bismuth, nickel, titanium and the like. The content of the foreign element in the alloy is at most 10% by weight or less. Aluminum which is particularly preferred in the present invention is pure aluminum. However, completely pure aluminum is difficult to produce due to refining technology, and therefore may contain a slightly different element. As described above, the composition of the aluminum plate applied to the present invention is not specified, and an aluminum plate of a conventionally known and used material can be appropriately used. The thickness of the aluminum plate used in the present invention is about 0.1 mm to 0.6 mm, preferably 0.15 mm to 0.4 mm, particularly preferably 0.2 mm to 0.8 mm.

Prior to roughening the aluminum plate, if necessary, a degreasing treatment with, for example, a surfactant, an organic solvent or an alkaline aqueous solution is performed to remove rolling oil on the surface. The surface roughening treatment of the surface of the aluminum plate is performed by various methods, for example, a method of mechanically roughening the surface, a method of electrochemically dissolving the surface, and a method of selectively dissolving the surface chemically. It is performed by the method of causing. As a mechanical method, a known method such as a ball polishing method, a brush polishing method, a blast polishing method, and a buff polishing method can be used. Further, as an electrochemical surface roughening method, there is a method of performing an alternating or direct current in a hydrochloric acid or nitric acid electrolyte. Further, a method combining both of them can be used as disclosed in JP-A-54-63902. The aluminum plate thus roughened is subjected to an alkali etching treatment and a neutralization treatment, if necessary, and then subjected to an anodic oxidation treatment, if desired, in order to increase the water retention and abrasion resistance of the surface. As the electrolyte used for the anodic oxidation treatment of the aluminum plate, various electrolytes that form a porous oxide film can be used. Generally, sulfuric acid,
Phosphoric acid, oxalic acid, chromic acid or a mixed acid thereof is used. The concentration of these electrolytes is appropriately determined depending on the type of the electrolyte.

The anodizing treatment conditions vary depending on the electrolyte used and cannot be specified unconditionally. However, in general, the concentration of the electrolyte is 1 to 80% by weight, the solution temperature is 5 to 70 ° C., and the current density is 5 to 60 A. / Dm ² , a voltage of 1 to 100 V, and an electrolysis time of 10 seconds to 5 minutes are appropriate. When the amount of the anodic oxide film is less than 1.0 g / m ² , the printing durability is insufficient or the non-image portion of the lithographic printing plate is easily scratched,
So-called "scratch stains" in which ink adheres to scratches during printing are likely to occur. After the anodizing treatment, the aluminum surface is subjected to a hydrophilic treatment as necessary. U.S. Pat. Nos. 2,7,7
No. 14,066, No. 3,181,461, No. 3,2
There is an alkali metal silicate (e.g., sodium silicate aqueous solution) method as disclosed in U.S. Pat. Nos. 80,734 and 3,902,734. In this method, the support is immersed in an aqueous solution of sodium silicate or electrolytically treated. In addition, potassium fluoride zirconate disclosed in JP-B-36-22063 and U.S. Pat. Nos. 3,276,868 and 4,158,461.
And the method of treating with polyvinyl phosphonic acid as disclosed in JP-A No. 4,689,272.

In the lithographic printing plate material according to the present invention, an undercoat layer can be provided on the support, if necessary. As the undercoat layer component, various organic compounds are used, for example, carboxymethyl cellulose, dextrin, gum arabic, phosphonic acids having an amino group such as 2-aminoethylphosphonic acid, and phenylphosphonic acid optionally having a substituent Organic phosphonic acids such as naphthylphosphonic acid, alkylphosphonic acid, glycerophosphonic acid, methylenediphosphonic acid and ethylenediphosphonic acid, phenylphosphoric acid which may have a substituent, naphthylphosphoric acid, alkylphosphoric acid and glycerophosphoric acid Organic phosphinic acid, optionally substituted phenylphosphinic acid, naphthylphosphinic acid, organic phosphinic acid such as alkylphosphinic acid and glycerophosphinic acid, amino acids such as glycine and β-alanine, and hydrochloric acid of triethanolamine Hydroxy such as salt -Alanine, and hydrochlorides of amines having a group may be used in combination of two or more. The coating amount of the organic undercoat layer is suitably from ² to 200 mg / m ² .

As described above, a lithographic printing plate using the lithographic printing plate material according to the present invention can be produced. This lithographic printing plate material has a wavelength of 760 nm to 120.
Image exposure is performed by a solid-state laser and a semiconductor laser that emit 0-nm infrared light. In the present invention, the developing treatment may be performed immediately after the laser irradiation, but if necessary, a heating treatment may be performed between the laser irradiation step and the developing step. The conditions of the heat treatment are as follows.
It is preferably performed for 0 seconds to 5 minutes. This heat treatment may reduce the laser energy required for recording during laser irradiation.

After performing a heat treatment as required, the lithographic printing plate material according to the present invention is developed with an alkaline aqueous solution. As the developer and replenisher for the lithographic printing plate material according to the present invention, conventionally known alkaline aqueous solutions can be used. For example, sodium silicate, potassium silicate, sodium triphosphate, potassium triphosphate, third
Ammonium phosphate, dibasic sodium phosphate, dibasic potassium phosphate, dibasic ammonium phosphate, sodium carbonate, potassium carbonate, ammonium carbonate, sodium bicarbonate, potassium bicarbonate, ammonium bicarbonate, sodium borate, potassium borate, boric acid Ammonium,
And inorganic alkali salts such as sodium hydroxide, ammonium hydroxide, potassium hydroxide and lithium hydroxide. Also, monomethylamine, dimethylamine, trimethylamine, monoethylamine, diethylamine, triethylamine, monoisopropylamine, diisopropylamine, triisopropylamine, n-butylamine, monoethanolamine, diethanolamine, triethanolamine, monoisopropanolamine, diisopropanolamine, Organic alkali agents such as ethyleneimine, ethylenediamine and pyridine are also used. These alkali agents are used alone or in combination of two or more.

Among these alkaline agents, particularly preferred developers are aqueous solutions of silicates such as sodium silicate and potassium silicate. The reason is that the developability can be adjusted by the ratio and the concentration of the silicon oxide SiO ₂ and the alkali metal oxide M ₂ O which are the components of the silicate. For example, JP-A-54-62004 discloses Tokiko 57-74
An alkali metal silicate described in No. 27 is effectively used.

In the case of further developing using an automatic developing machine, an aqueous solution having a higher alkali strength than the developing solution (replenisher)
It has been known that a large amount of lithographic printing plate material can be processed without replacing the developing solution in the developing tank for a long time by adding to the developing solution. This replenishment system is also preferably applied in the present invention. Various surfactants and organic solvents can be added to the developing solution and the replenishing solution as required for the purpose of accelerating or suppressing the developing property, dispersing the developing residue and improving the ink affinity of the printing plate image area. Preferred surfactants include anionic, cationic, nonionic and amphoteric surfactants. Further, if necessary, the developer and replenisher may be hydroquinone, resorcin, sulfurous acid,
A reducing agent such as a sodium salt or a potassium salt of an inorganic acid such as bisulfite, an organic carboxylic acid, an antifoaming agent, and a water softener can also be added. The printing plate developed using the above developer and replenisher is post-treated with washing water, a rinsing solution containing a surfactant and the like, and a desensitizing solution containing gum arabic and a starch derivative. When the lithographic printing plate material according to the present invention is used as a printing plate material, these processes can be used in various combinations as a post-treatment.

In recent years, in the plate making and printing industry, automatic developing machines for printing plate materials have been widely used in order to rationalize and standardize plate making operations. This automatic developing machine generally consists of a developing section and a post-processing section, and consists of a device for transporting printing plate material, each processing solution tank and a spray device, and pumps the exposed printing plate horizontally while pumping it. Each processing liquid is sprayed from a spray nozzle to perform development processing.
Recently, a method has been known in which a printing plate material is immersed and transported by a submerged guide roll or the like in a processing liquid tank filled with a processing liquid, and the processing is performed. In such an automatic processing, the processing can be performed while replenishing each processing liquid with a replenisher according to the processing amount, the operating time, and the like. Further, a so-called disposable processing method in which processing is performed with a substantially unused processing liquid can also be applied.

The lithographic printing plate obtained as described above can be subjected to a printing step after applying a desensitized gum if desired, but when it is desired to obtain a lithographic printing plate having a higher printing durability. Is subjected to a burning process. If you plan to burn the lithographic printing plate,
It is preferable to treat with a surface-regulating liquid as described in JP-B-61-2518, JP-B-55-28062, JP-A-62-31859 and JP-A-61-159655. As a method, a sponge or absorbent cotton impregnated with the surface conditioning liquid is applied on a lithographic printing plate, or a method in which the printing plate is immersed in a vat filled with the surface conditioning solution and applied, Application by an automatic coater or the like is applied. Also,
Making the amount of the coating uniform with a squeegee or a squeegee roller after the coating gives more preferable results. The application amount of surface conditioning liquid is generally 0.03 to 0.8 g
/ M ² (dry weight) is appropriate.

The lithographic printing plate to which the surface conditioning liquid has been applied is dried, if necessary, and then heated to a high temperature by a burning processor (for example, BP-1300, a burning processor sold by Fuji Photo Film Co., Ltd.). Is done. The heating temperature and time in this case depend on the type of the component forming the image, but may be 1 to 180 ° C. to 300 ° C.
A range of up to 20 minutes is preferred. The burned lithographic printing plate can be subjected to conventional treatments such as washing with water and gumming, if necessary, but a surface conditioning liquid containing a water-soluble polymer compound or the like is used. In such a case, a so-called desensitizing treatment such as gumming can be omitted. The lithographic printing plate obtained by such a process is set on an offset printing machine or the like and used for printing a large number of sheets.

[0106]

The present invention will be described below in detail with reference to examples.
However, the present invention is not limited to these.Example 1 0.30mm thick aluminum plate (material 1050)
After washing with trichlorethylene and degreasing,
And a 400 mesh pumicestone-water suspension.
Was grained and washed well with water. 45
Dipped in a 25% aqueous solution of sodium hydroxide for 9 seconds.
After washing with water, further 2% HNO _Three20 seconds
It was immersed in water for washing. Etching on the grained surface at this time
Approximately 3 g / m^TwoMet. Next, this plate is_TwoS
O_FourCurrent density 15A / dm^Two3g / m
^Two, And then washed with water and dried. next
The following undercoating liquid is applied to this aluminum plate,
Dry for 30 seconds. The amount of coating after drying is 10 mg / m^TwoIn
Was.

(Undercoat solution) 0.1 g of β-alanine 0.05 g of phenylphosphonic acid 40 g of methanol 60 g of pure water Further, the following photosensitive solution was applied to this aluminum plate to prepare a positive type lithographic printing plate. did.

(Photosensitive solution) ・ Infrared absorbing dye (compound 1) 0.10 g ・ Esterified product of naphthoquinone-1,2-diazide-sulfonyl chloride and pyrogallol-acetone resin (US Pat. No. 3,635,709) Novolak resin obtained from cresol and formaldehyde (meta: para ratio = 6: 4, weight average molecular weight 1800) 2.00 g p-octylphenol-formaldehyde novolak 0 .02 g Naphthoquinone-1,2-diazido-4-sulfonyl chloride 0.01 g Tetrahydrophthalic anhydride 0.05 g 4- (pN, N-bis (ethoxycarbonylmethyl) aminophenyl) -2,6- Bis (trichloromethyl) -s-triazine 0.02 g pN- (p-hydroxybenzoyl) aminophenyl) -2,6-bis (trichloromethyl) -s-triazine 0.02 g Dye in which the counter ion of Victoria Pure Blue BOH is converted to 1-naphthalene-sulfonic acid 0 0.03 g-Megafac F-177 (manufactured by Dainippon Ink and Chemicals, Inc., fluorine-based surfactant) 0.06 g-Methyl ethyl ketone 20 g-Methyl alcohol 7 g

The obtained positive type lithographic printing plate material was exposed with a YAG laser adjusted to a plate surface output of 2 W, and then developed by Fuji Photo Film Co., Ltd., DP-4 (1: 8), rinse solution FR -3 (1: 7) through an automatic processor. The sensitivity was 90 mJ / cm ² . Subsequently, the plate surface was treated with gum GU-7 (1: 1) manufactured by Fuji Photo Film Co., Ltd., and printing was performed with a Heidel KOR-D machine. 70,000 good prints without stains on the non-image area were obtained.

Next, the positive type lithographic printing plate material was heated at a temperature of 4 ° C.
It was left for 3 days in a durable environment of 5 ° C. and 75% relative humidity, and was exposed, processed and printed in the same manner as described above. Good printed matter was obtained.

Comparative Example 1 A positive type lithographic printing plate was prepared in the same manner as in Example 1, except that 0.20 g of IRG-022 (a diimmonium dye manufactured by Nippon Kayaku Co., Ltd.) was used as the infrared absorbing dye. . When the same laser exposure and development processing as in Example 1 were performed, the sensitivity was 300 mJ / cm ² , and a residual color was generated in the non-image portion. When this plate was printed under the same conditions as in Example 1, printing stains occurred on the non-image area.

Example 2 As an infrared absorbing dye, 0.10 g of Compound 1 was added to
RG-022 (a diimmonium dye manufactured by Nippon Kayaku Co., Ltd.)
A positive planographic printing plate was prepared in the same manner as in Example 1 except that a mixture with 10 g was used. When the same laser exposure and development processing as in Example 1 were performed, 100 mJ
/ Cm ² . This plate was excellent in durability at the time of printing. When printing was performed under the same conditions as in Example 1, a good printed matter having no stain on the non-image portion was 80,000.
Were obtained.

Next, the positive type lithographic printing plate material was heated at a temperature of 4 ° C.
It was left for 3 days in a durable environment of 5 ° C. and 75% relative humidity, and was exposed, processed and printed in the same manner as described above. Good printed matter was obtained.

Example 3 A positive type lithographic printing plate was prepared in the same manner as in Example 1, except that Compound 26 was used as an infrared absorbing dye. Using a semiconductor laser (wavelength: 825 nm, beam diameter: 1 / e ² = 6 μm) as a heat mode laser, the obtained positive type lithographic printing plate material was subjected to a linear velocity of 8 m / sec.
The exposure was adjusted to a plate output of 110 mW with c. After exposure 1
After a heat treatment at 10 ° C. for 1 minute, a developing solution manufactured by Fuji Photo Film Co., Ltd., DP-4 (1: 8), a rinsing solution FR-
3 (1: 7) through an automatic processor.
The sensitivity was 100 mJ / cm ² . Subsequently, the plate surface was treated with gum GU-7 (1: 1) manufactured by Fuji Photo Film Co., Ltd., and printing was performed with a Heidel KOR-D machine. 65,000 good prints with no stain on the non-image area were obtained.

Next, the positive type lithographic printing plate was heated at a temperature of 4 ° C.
It was left for 3 days in a durable environment of 5 ° C. and 75% relative humidity, and was exposed, processed and printed in the same manner as described above. Good printed matter was obtained.

Example 4 An aluminum plate having a thickness of 0.24 mm was grained with a nylon brush and a 400-mesh pumistone-water suspension, and then thoroughly washed with water to prepare a substrate [I]. Substrate [I] was placed in 10% sodium hydroxide at 70 ° C for 2 hours.
After immersion for 0 seconds and etching, after washing with running water, 20%
Neutralized washing with HNO ₃ , washing with water, and 4% in 0.7% nitric acid aqueous solution using a sinusoidal alternating waveform current at 12.7 V
Electrolytic surface roughening treatment was performed at an amount of electricity of 00 coulomb / dm ² , and the substrate was washed with water to prepare a substrate [II].

The substrate [II] was treated in a 10% aqueous sodium hydroxide solution so that the amount of the surface dissolved was 0.9 g / m ² . After washing with water, neutralization and washing were performed in a 20% nitric acid solution to perform desmutting, and then anodizing was performed in an 18% nitric acid aqueous solution so that the amount of the oxide film was 3 g / m ² . Next, the following photosensitive solution was prepared, applied on the anodized aluminum plate, and dried at 100 ° C. for 2 minutes to prepare a positive type lithographic printing plate. The coating amount at this time was 2.3 in dry weight.
g / m ² .

(Composition of Photosensitive Solution) Esterified product of 2,3,4-trihydroxybenzophenone and naphthoquinone-1,2-diazide-5-sulfonyl chloride (esterification ratio: 90 mol%) 0.45 g · N-(p-amino sulfonyl phenyl) copolymer of methacrylic Ami de and methyl methacrylate (described in example 1 of European Patent No. 330,239 (a ₂₎ Pat) 1.70 g・ Naphthalene-2-sulfonic acid 0.007 g ・ Cresol (meta form 60%, ortho form 40%)-formaldehyde resin (weight average molecular weight; 4,000) 0.70 g ・ 2- (p-methoxyphenyl)- 4,6-bis (trichloromethyl) -s-triazine 0.02 g naphthoquinone-1,2-diazide-sulfonyl chloride 1 g ・ Victoria Pureable-BOH (Dye manufactured by Hodogaya Chemical Co., Ltd.) 0.015 g ・ Infrared absorbing dye (compound 1) 0.2 g ・ MegaFac F-177 (Dainippon Ink & Chemicals, Inc.) Fluorinated surfactant) 0.004 g ・ Dimethylformamide 4 g ・ 1-Methoxy-2-propanol 9 g ・ Methyl ethyl ketone 7 g

The obtained positive type lithographic printing plate was subjected to plate surface output 2 W
Exposure with a YAG laser adjusted to DP-4 (trade name:
25 ° C with an 8-fold diluted aqueous solution of Fuji Photo Film Co., Ltd.)
For 60 seconds. Sensitivity is 90mJ / c
m ² .

The printing durability of the obtained lithographic printing plate was 45,000 when using UV ink and 90,000 when using oil-based ink.
It was excellent at 0 sheets. This lithographic printing plate is UV
It was excellent in resistance to the cleaning liquid for ink.

Next, the positive type lithographic printing plate material was heated at a temperature of 4 ° C.
It was left for 3 days in a durable environment of 5 ° C. and 75% relative humidity, and was exposed, processed and printed in the same manner as described above. Good printed matter was obtained.

[0122]

According to the present invention, plate making can be made directly from digital data of a computer or the like by using the above-mentioned specific infrared-absorbing dye, high sensitivity, excellent storage stability, excellent printability, and excellent printing stains. The present invention can provide a laser direct drawing type lithographic printing plate material which does not produce any problem.

Claims (3)

[Claims] 1. A laser direct drawing comprising an alkali-soluble binder, a substance that substantially reduces the alkali solubility of the binder, and an infrared absorbing dye that does not substantially lower the alkali solubility of the binder. Lithographic printing plate material. 2. The laser direct dye according to claim 1, wherein the infrared absorbing dye which does not substantially reduce the alkali solubility of the binder has a salt structure in which the counter ion is located within the same molecule. Lithographic printing plate material. 3. The lithographic printing plate material according to claim 1, further comprising an infrared absorbing dye which substantially reduces the alkali solubility of the binder.