JP2002148785A - Image forming material and original plate of planographic printing plate using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image forming material excellent in image forming properties and shelf stability and giving a high strength image and to provide an original plate of a planographic printing plate for direct plate making using the image forming material and excellent in printing resistance. SOLUTION: The image forming material contains (a) a high molecular compound insoluble in water and soluble in an aqueous alkali solution and (b) a crosslinker of formula (1) [where (n) is an integer of 1-3; (m) is an integer of >=1; the product of (n) and (m) is >=2; A1 is a monovalent organic group; A2 is a divalent organic group; Z is an m-valent organic group; and X is a divalent organic group selected from groups of formulae (2)-(6)], and when the image forming material is irradiated with active radiation, its solubility in the aqueous alkali solution is varied. Recording by exposure with IR is enabled by using (c) an IR absorber in combination with the components (a) and (b).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a positive-type or negative-type image-forming material capable of recording an image by exposure to an infrared laser and changing the solubility of a recording layer in an exposed portion, and a lithographic printing plate precursor using the same. , UV exposure, or
An image forming material suitable for a lithographic printing plate precursor for so-called direct plate making, which can be written by irradiation with actinic radiation such as exposure in the near infrared region such as an infrared laser and can be directly made from digital signals of a computer or the like. The planographic printing plate precursor used.

[0002]

2. Description of the Related Art In recent years, with the development of solid-state lasers and semiconductor lasers having a light emitting region from near infrared to infrared, as a system for making a plate directly from digital data of a computer,
Attention has been paid to those using these infrared lasers. A positive type lithographic printing plate material for infrared laser for direct plate making is disclosed in JP-A-7-285275. The present invention is an image recording material in which a substance that absorbs light and generates heat and a positive photosensitive compound such as quinonediazide compounds are added to an aqueous alkali solution-soluble resin, and the positive photosensitive compound is formed in an image area. However, it acts as a dissolution inhibitor that substantially lowers the solubility of the alkali aqueous solution-soluble resin, and is decomposed by heat in the non-image area to exhibit no dissolution inhibiting ability, so that it can be removed by development, and the image can be removed. Form. As a result of the study by the present inventors, it has been found that a positive image can be obtained without adding a quinonediazide compound to the image recording material. There is a disadvantage that the stability of the sensitivity to density, that is, the latitude of development is deteriorated.

On the other hand, it is known that onium salts and alkali-insoluble compounds capable of hydrogen bonding have an alkali dissolution inhibiting action of an alkali-soluble polymer. WO97 / 39894 describes that as an infrared laser-compatible image forming material, a composition using a cationic infrared absorbing dye as a dissolution inhibitor of an alkali water-soluble polymer exhibits a positive effect. This positive action is an action in which the infrared absorbing dye absorbs the laser beam and the generated heat causes the effect of suppressing the dissolution of the polymer film at the irradiated portion to disappear, thereby forming an image.

[0004] Such an image-forming material obtained by infrared laser exposure can exhibit sufficient image-forming properties on the surface irradiated with the laser, but cannot obtain a sufficient effect up to the deep part of the light-sensitive material due to thermal diffusion. Low, and in the case of the negative type, the curing of the recording layer in the image area is insufficient,
There was a problem that printing durability was low.

In order to solve this problem concerning printing durability,
A method of using a crosslinking agent for improving the strength of the recording layer has been proposed. For example, a positive type is disclosed in Japanese Patent Application Laid-Open No. 11-20248.
No. 1 discloses a technique of adding an amino group-containing compound such as a melamine derivative as a compound capable of crosslinking an alkali-soluble resin by the action of heat, but when an alkali-soluble resin other than a novolak resin is used, In addition, since the compatibility between the resin and the cross-linking agent is insufficient, sufficient improvement in printing durability cannot be obtained, and there is a problem of lack of versatility. As the negative type, Japanese Patent Application Laid-Open No. H11-254850 discloses a light-sensitive material using a cross-linking agent having a functional group such as an amide group. Because of having a functional group of, it is difficult to synthesize a multifunctional compound,
There are problems such as insufficient solubility in a solvent when the photosensitive layer is applied. As described above, it is the present condition that a means that can be used in combination with a general alkali-soluble resin, has excellent versatility, and has sufficient printing durability without sacrificing sensitivity or stability has been found yet. .

[0006]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide an image forming material which is excellent in image formability and storage stability and has high strength of an obtained image, and a direct plate making using the same. It is an object of the present invention to provide a lithographic printing plate precursor excellent in printing durability capable of forming an image by irradiation with actinic radiation.

[0007]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies with the aim of improving the strength and storage stability of the formed image, and as a result, have a specific structure and are generally used as image forming materials. By adding a crosslinking agent having excellent compatibility with resins, it was found that both the image forming property and the strength and storage stability of the obtained image were improved, and the present invention was completed. .

That is, the image forming material according to claim 1 of the present invention comprises (a) a polymer compound which is insoluble in water and soluble in an aqueous alkali solution, and (b) a compound represented by the following general formula (1): It contains a cross-linking agent represented by the formula (1), and is characterized in that the solubility in an alkaline aqueous solution is changed by irradiation with actinic radiation.

[0009]

Embedded image

In the formula, n is an integer of 1 to 3, m is an integer of 1 or more, and the product of n and m is 2 or more. A ¹ represents a monovalent organic group, A ² represents a divalent organic group, Z represents an m-valent organic group,
X represents a divalent organic group selected from the following.

[0011]

Embedded image Further, the image forming material according to claim 2 of the present invention is capable of recording by a heat mode, and (a) a polymer compound which is insoluble in water and soluble in an aqueous alkali solution;
(B) a crosslinking agent represented by the general formula (1), and (c)
It contains an infrared absorbing agent, and its solubility in an alkaline aqueous solution is changed by infrared exposure.

A lithographic printing plate precursor according to the present invention according to claim 3 is characterized in that the lithographic printing plate precursor has a recording layer made of any one of the above-mentioned image forming materials on a support.

Although the function of the present invention is not clear, since a cross-linking agent having a hydrogen-bonding interacting group such as amide, urethane or urea is used, compatibility with the alkali-soluble resin used in combination and solvent High solubility, not only image formation by cross-linking formation in negative type, but also when used as a positive photosensitive material, high compatibility with alkali-soluble resins other than novolak resin, image recording material using various resins It is considered that the printing durability can be improved by the heat treatment after exposure and development. Further, the interaction network with the alkali-soluble resin is strengthened by the action of such a hydrogen-bonding interaction group, and the aging of the interaction is suppressed, so that the storage stability is improved. Furthermore, since a specific functional group is not required for the mother skeleton of the crosslinking agent according to the present invention,
It is easy to synthesize a polyfunctional crosslinking agent, and even when a polyfunctional compound is formed, as described above, the solubility in a solvent is high, so that various image recording materials can be added to a photosensitive solution. It also has such advantages.

In the present invention, "corresponding to heat mode" means that recording by heat mode exposure is possible. The definition of the heat mode exposure in the present invention will be described in detail. Hans-Joachim Tim
pe, IS & Ts NIP 15: 1999 Inte
rational Conference on D
digital printing technology
ies. P. As described in 209, a photoabsorbing substance (for example, a dye) is photoexcited in a photoreceptor material, and undergoes a chemical or physical change to form a chemical or physical change from the photoexcitation of the photoabsorbing substance forming an image. It is known that there are roughly two modes in the above processes. One is that the photoexcited light absorbing substance is deactivated by some photochemical interaction (eg, energy transfer, electron transfer) with other reactants in the photosensitive material,
As a result, a so-called photon mode in which the activated reactant causes a chemical or physical change required for the above-described image formation, and the other is that the photoexcited light absorbing substance generates heat and deactivates, and the heat is lost. This is a so-called heat mode in which a reactant causes a chemical or physical change required for image formation using the above-described method. In addition, there are special modes such as ablation in which substances are explosively scattered by the energy of light locally collected and multiphoton absorption in which one molecule absorbs many photons at a time, but these modes are omitted here.

The exposure processes using the above modes are called photon mode exposure and heat mode exposure. The technical difference between photon mode exposure and heat mode exposure is whether or not the energy amount of several photons to be exposed can be added to the energy amount of the target reaction.
For example, consider a case where a certain reaction is caused by using n photons. In photon mode exposure, photochemical interaction is used, so that the energy of one photon cannot be added together due to the requirement of the law of conservation of quantum energy and momentum. That is, in order to cause a certain reaction, the relationship of “energy amount of one photon ≧ energy amount of reaction” is necessary. On the other hand, in heat mode exposure, heat is generated after light excitation, and light energy is converted into heat and used, so that the amount of energy can be added. Therefore, the relationship “energy amount of n photons ≧ energy amount of reaction” is sufficient. However, this energy addition is restricted by thermal diffusion. That is, if the next photoexcitation-deactivation process occurs and heat is generated before the heat escapes from the exposed portion (reaction point) of interest by thermal diffusion, the heat is reliably accumulated and added, and the temperature rises in that portion. Leads to. However, when the next heat is generated slowly, the heat escapes and is not accumulated. In other words, in the heat mode exposure, the result is different between the case of irradiating a high energy light for a short time and the case of irradiating a low energy light for a long time even at the same total exposure energy. It becomes advantageous for accumulation of.

Of course, in the photon mode exposure, a similar phenomenon may occur due to the influence of the diffusion of the subsequent reactive species, but basically, such a phenomenon does not occur. That is, in terms of the characteristics of the photosensitive material, in the photon mode, the intrinsic sensitivity of the photosensitive material (the energy required for the reaction required for image formation) is compared with the exposure power density (w / cm ² ) (= energy density per unit time). Amount) is constant, but in the heat mode, the intrinsic sensitivity of the photosensitive material increases with respect to the exposure power density. Therefore, if the exposure time is fixed such that the productivity necessary for practical use as an image recording material can be maintained, the photon mode exposure usually has a high sensitivity of about 0.1 mJ / cm ² when comparing the modes. Reaction can be achieved at any low exposure, although
The problem of low-exposure fog in unexposed areas is likely to occur. On the other hand, in the heat mode exposure, a reaction does not occur unless the exposure amount exceeds a certain value, and usually about 50 mJ / cm ² is required in relation to the thermal stability of the photosensitive material. Is avoided. In fact, in heat mode exposure, the exposure power density on the plate surface of the photosensitive material is 500
0 w / cm ² or more, preferably 10,000
w / cm ² or more is required. However, although not described in detail here, when a high power density laser of 5.0 × 10 ⁵ / cm ² or more is used, ablation occurs, which is not preferable because of problems such as soiling the light source.

[0017]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail. The image forming material of the invention is characterized by containing a crosslinking agent having a specific structure. First, a description will be given of a crosslinking agent which is a characteristic component. [(B) Crosslinking Agent Represented by General Formula (1)] The crosslinking agent used in the present invention is represented by the following general formula (1). This is hereinafter referred to as a specific crosslinking agent as appropriate.

[0018]

Embedded image

In the formula, n is an integer of 1 to 3, m is an integer of 1 or more, and the product of n and m is 2 or more. A ¹ represents a monovalent organic group, and A ² represents a divalent organic group. A ¹ is preferably a monovalent hydrocarbon group, particularly preferably an alkyl group having 1 to 8 carbon atoms or an aryl group having 6 to 12 carbon atoms. A ² is preferably a divalent hydrocarbon group,
It is preferably an alkylene group having 2 to 8 carbon atoms or an arylene group having 6 to 12 carbon atoms, and particularly preferably an alkylene group having 2 to 8 carbon atoms. These organic groups include an alkyl group having 1 to 12 carbon atoms, an aryl group having 6 to 20 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, and a
20, aryloxy groups, halogen atoms, alkylthio groups, acyloxy groups, amino groups, alkylcarbonyl groups, arylcarbonyl groups, alkoxycarbonyl groups,
Aryloxycarbonyl group, alkylsulfonyl group,
It may have a substituent selected from an arylsulfonyl group, an alkoxysulfonyl group, an aryloxysulfonyl group, a carboxy group, a hydroxyl group, a cyano group, and a nitro group, and preferred substituents include an alkyl group, an aryl group, and an alkoxy group. And aryloxy groups. Z
Represents an m-valent organic group, and is preferably an m-valent hydrocarbon group, wherein the hydrocarbon group has at least one substituent which A ¹ and A ² may have. Is also good. Further, the divalent organic group portion in the hydrocarbon group is represented by -O-, -S-, -CO
-, -COO-, -CONH-, -NHCONH-,-
_{NHCOO -, - SO 2 -,} - SO 2 O -, - SO 2 NH
-, - CONH-SO ₂ - may be substituted with a divalent organic group selected from. X represents a divalent organic group selected from the following.

[0020]

Embedded image

The specific crosslinking agent used in the present invention is a known phenol compound, for example, Japanese Patent Application Laid-Open No. 1-2899.
No. 46, JP-A-3-179353, JP-A-3-200252, JP-A-3-128959, JP-A-3-200254, JP-A-5-1582
No. 33, JP-A-5-224409 and the like, a phenol compound (1B) and formaldehyde are reacted in a strongly alkaline medium at a temperature of about 0 to 80 ° C, preferably 10 to 60 ° C for 1 to 30 hours. The general formula (1A)
The compound represented by is obtained. Thereafter, under an acidic condition, the alcohol represented by A ¹ -X-A ² -OH and 0 to 0
By reacting at 80 ° C. for 1 to 30 hours, a crosslinking agent represented by the general formula (1) is obtained. The temperature at the time of reacting with alcohol is preferably from 20 to 80 ° C. The synthesis scheme is shown below.

[0022]

Embedded image

The compound represented by the general formula (1B) is not particularly limited as long as it is a phenolic compound, and can be used arbitrarily. For example, in addition to mononuclear phenols such as phenol and cresol, Polynuclear phenol derivatives described in JP-A-8-276558, JP-A-10-23
A phenolic compound having a specific functional group described in JP-A-4772 can be suitably used. The general formula (1
The compound represented by A) can be used without limitation as long as it is a reaction product of the compound represented by the general formula (1B) and formaldehyde, and 2,6-bis (hydroxymethyl) -p- In addition to commercially available compounds such as cresol, a polynuclear phenol derivative described in JP-A-8-276558, a phenolic compound derivative having a specific functional group described in JP-A-11-254850, a resole resin, and the like are preferably used. be able to. The alcohol that reacts with the compound represented by the general formula (1A) under acidic conditions is A ¹
—X—A ² —OH, A ¹ , A ² , Z
And X have the same meanings as in the general formula (I). Specific examples [(KZ-1) to (KZ-1)) in which a mother skeleton having a specified functional group is defined as a crosslinking agent suitably used in the present invention.
(KZ-18)] is shown below, but the present invention is not limited thereto. In the following formula, Y is -C
H ₂ —OA ² —X—A ¹ or —CH ₂ —OH,
At least one of Y is ^{_{-CH 2 -O-A 2 -X-}} A 1
In and, -CH ^₂ -O-A ₂ to the total Y in the compound -
A mixture of compounds having different ratios of XA ¹ groups may be used.

[0024]

Embedded image

[0025]

Embedded image

[0026]

Embedded image

The following is an example of the synthesis of the specific crosslinking agent according to the present invention.
Show. [Synthesis Example 1: Synthesis of Crosslinking Agent (KZ-2)] 2,6-bis
(Hydroxymethyl) -p-cresol (Sigma Aldo
Rich Japan Co., Ltd.) 20 g and N-acetyl ethano
Mixed with concentrated sulfuric acid while stirring.
A mixture of 2.4 g and 10 ml of N-acetylethanolamine
The mixture was slowly added dropwise. Heat to 50 ° C and react for 3 hours
Then, it was cooled to room temperature. Filtration of insolubles in the reaction solution
The reaction solution was poured into 1500 ml of water,
15.3 g of agent (KZ-2) were obtained. Any of the crosslinking agents Y
Also -CH_TwoOCH_TwoCH _TwoNHCOCH_ThreeOf what is
Is 81% as a result of HPLC analysis (detection wavelength 282 nm)
there were.

[Synthesis Example 2: Synthesis of Crosslinking Agent (KZ-9)]
5,5 ′-(1- (1- (3,5-bis (hydroxymethyl) -4-hydroxyphenyl) -1-methyl) phenyl) ethylidene) bis (2-hydroxy-1,3-benzenedimethanol) 40 g of hexamethylol TrisP-PA (manufactured by Honshu Chemical Co., Ltd.) and 300 ml of 2-methanesulfonylethanol were mixed, and a mixture of 5 g of concentrated sulfuric acid and 20 ml of 2-methanesulfonylethanol was slowly added dropwise with stirring. After heating to 50 ° C. and reacting for 4 hours, the mixture was cooled to room temperature. The insolubles in the reaction solution were separated by filtration, and the reaction solution was poured into 3000 ml of ice water to obtain 62.5 g of a precipitated crosslinking agent (KZ-9). The proportion of Y of the cross-linking agent are all a _{-CH 2 OCH 2 CH 2 SO 2} CH 3 is H
The result of PLC analysis (detection wavelength: 282 nm) was 76%.

[Synthesis Example 3: Synthesis of Crosslinking Agent (KZ-10)] 5,5 '-(1- (1- (1,5-bis (hydroxymethyl) -4-hydroxyphenyl) -1-methyl)
Phenyl) ethylidene) bis (2-hydroxy-1,3
-Benzenedimethanol) (40 g of hexamethylol TrisP-PA manufactured by Honshu Chemical Co., Ltd.) and 300 ml of N-acetylethanolamine were mixed, and a mixture of 5 g of concentrated sulfuric acid and 20 ml of N-acetylethanolamine was slowly added dropwise with stirring. After heating to 50 ° C. and reacting for 3 hours, it was cooled to room temperature. The insolubles in the reaction solution are filtered off,
The reaction solution was poured into 3000 ml of water to obtain 32.6 g of a precipitated crosslinking agent (KZ-10). Y of the crosslinking agent is all-
The proportion of CH ₂ OCH ₂ CH ₂ NHCOCH ₃ is H
As a result of PLC analysis (detection wavelength: 282 nm), it was 78%.

When the specific crosslinking agent is added to the image forming material of the present invention, only one kind may be added, or two or more kinds may be mixed and used. In the present invention, the amount of addition of these specific crosslinking agents is based on the total solid content of the image forming material.
It is used in an amount of 0.2 to 60% by weight, preferably 0.5 to 30% by weight. When the addition amount of the crosslinking agent is less than 0.2% by weight, the film strength of the image portion at the time of image recording deteriorates,
On the other hand, when the content exceeds 60% by weight, the coating property of the image area is deteriorated, and the dissolution contrast between the image area and the non-image area tends to decrease.

The image recording material of the present invention is a material whose solubility in an aqueous alkali solution is changed by irradiation with actinic rays such as ultraviolet light exposure and infrared light exposure. By developing the aqueous solution, a positive or negative image is formed.
Hereinafter, various recording layers will be described. In such a recording layer, the alkali developability is reduced by irradiation with actinic rays, the developability is improved in contrast to the negative type in which the irradiated (exposed) part is an image area, and the irradiated (exposed) part is non-image The area is divided into two types, positive type.

Examples of the negative recording layer include known acid-catalyzed crosslinking (including cationic polymerization) recording layers. In these, an acid generated by light irradiation or heating serves as a catalyst, and a compound constituting the recording layer causes a crosslinking reaction and cures to form an image area.

Examples of the positive recording layer include a known acid-catalyzed decomposition system, an o-quinonediazide compound-containing system, and an interaction canceling (thermosensitive positive) recording layer. These become soluble in water or alkaline water by the action of releasing the bond of the polymer compound forming the layer by the acid or thermal energy itself generated by light irradiation or heating, and are removed by development to remove the non-polymer. This forms an image portion. Hereinafter, each recording layer will be described in detail.

<Acid Crosslinked Layer> The acid crosslinked layer in the present invention comprises:
A compound that generates an acid by light or heat (hereinafter, referred to as an acid generator), the specific crosslinking agent according to the present invention that causes a crosslinking reaction by using the generated acid as a catalyst, and a layer containing these compounds. And a binder polymer capable of reacting with a crosslinking agent in the presence of an acid. In this acid crosslinked layer, the acid generated by the decomposition of the acid generator by light irradiation or heating functions as a catalyst for the reaction of the specific crosslinking agent, and between the crosslinking agents or between the crosslinking agent and the binder polymer. A strong crosslinked structure is formed, which reduces the alkali solubility and becomes insoluble in the developer.

The acid-crosslinked layer of the present invention contains an acid generator, a crosslinking agent (component (b)), a binder polymer (component (a)) as a component crosslinked by the crosslinking agent, and others. Next, these compounds will be individually described. (Acid Generator) In the present invention, the compound (acid generator) that generates an acid by light or heat is referred to as infrared ray irradiation, 100 ° C.
It refers to a compound that decomposes by heating to generate an acid.
As the generated acid, pKa such as sulfonic acid and hydrochloric acid is 2
The following strong acids are preferred. Examples of the acid generator suitably used in the present invention include onium salts such as iodonium salts, sulfonium salts, phosphonium salts, and diazonium salts. Specifically, US 4,708,9
No. 25 and compounds described in JP-A-7-20629. Particularly, an iodonium salt, a sulfonium salt, and a diazonium salt having a sulfonate ion as a counter ion are preferable. Examples of the diazonium salt include diazonium compounds described in US Pat. No. 3,867,147.
The diazonium compounds described in U.S. Pat. No. 2,632,703, JP-A-1-102456 and JP-A-1-
The diazo resin described in each publication of 102457 is also preferable. Also, US 5,135,838 and US 5,
Benzyl sulfonates described in JP 200,544 are also preferred. Further, JP-A-2-100054,
JP-A-2-100055 and JP-A-9-197671
The active sulfonic acid esters and disulfonyl compounds described in the above item are also preferred. In addition, JP-A-7-2710
No. 29, haloalkyl-substituted S-
Triazines are also preferred.

These acid generators are used in an amount of 0.01 to 50% by weight, preferably 0.1 to 40% by weight, more preferably 0.5 to 30% by weight based on the total solid content of the acid crosslinked layer. It is added in the crosslinked layer. If the amount is less than 0.01% by weight, no image can be obtained. On the other hand, if the amount exceeds 50% by weight, non-image areas are stained during printing.

These compounds may be used alone,
Also, two or more kinds may be used in combination. Note that the acid generators listed here can also be decomposed by irradiation with ultraviolet light, and thus, if a recording layer having such a form is used, image recording can be performed not only by irradiation with infrared light but also by irradiation with ultraviolet light.

(Acid Crosslinking Agent) The crosslinking agent that can be used in the acid crosslinking layer of the present invention refers to the specific crosslinking agent (b) already described in detail.
In addition, as long as the effect of the present invention is not impaired, a known compound which is crosslinked with an acid can be appropriately used in combination. Such a known crosslinking agent is not particularly limited. For example, a phenol derivative represented by the following general formula (I) (hereinafter, appropriately referred to as a low molecular weight phenol derivative) and a phenol derivative represented by the following general formula (II) A polynuclear phenolic crosslinking agent having three or more phenol rings having two or three hydroxymethyl groups on the ring in the molecule, and the low-molecular-weight phenol derivative and a polynuclear phenolic crosslinking agent and / or Alternatively, a mixture with a resole resin is preferably used.

[0039]

Embedded image

In the formula, Ar ¹ represents an aromatic hydrocarbon ring which may have a substituent. R ¹ and R ² may be the same or different and each represent a hydrogen atom or a hydrocarbon group having 12 or less carbon atoms. R ³ represents a hydrogen atom or a hydrocarbon group having 12 or less carbon atoms. m is 2 to 4
Indicates an integer. n shows the integer of 1-3. X represents a divalent linking group, and Y represents a monovalent to 4 group having the above partial structure.
A valent linking group or a functional group whose terminal is a hydrogen atom,
Z represents a monovalent to tetravalent linking group or a functional group that is absent when Y is a terminal group or exists depending on the number of linking groups of Y.

[0041]

Embedded image

In the formula, A represents an r-valent hydrocarbon linking group having 1 to 20 carbon atoms, and r represents an integer of 3 to 20. p is
Shows an integer of 2 to 3. The phenol derivative represented by the general formula (I) is disclosed in
000-35669, a polynuclear phenol represented by the general formula (II) and having three or more phenol rings in the molecule having two or three hydroxymethyl groups on the ring. The crosslinking agent is also described in detail in the publication.

These crosslinking agents may be used alone,
Also, two or more types may be used in combination. The amount of the known crosslinking agent that can be used in combination with the present invention is in the range of 0 to 75% by weight, preferably 0 to 50% by weight, based on the specific crosslinking agent. If the amount of the specific crosslinking agent added is less than 25% by weight based on all the crosslinking agent components, the effects of the present invention such as improvement in the film strength of the image area and storage stability may be impaired.

As the (a) binder polymer which can be used in the acid cross-linking layer of the present invention, a polymer having an aromatic hydrocarbon ring directly bonded to a hydroxy group or an alkoxy group in a side chain or a main chain is exemplified. As the alkoxy group, those having 20 or less carbon atoms are preferable from the viewpoint of sensitivity. As the aromatic hydrocarbon ring, a benzene ring, a naphthalene ring or an anthracene ring is preferable from the viewpoint of availability of raw materials. These aromatic hydrocarbon rings may have a substituent other than a hydroxy group or an alkoxy group, for example, a substituent such as a halogen group or a cyano group, but from the viewpoint of sensitivity, other than a hydroxy group or an alkoxy group. It is preferable not to have a substituent of

In the present invention, a binder polymer that can be suitably used is a polymer having a structural unit represented by the following general formula (III) or a phenol resin such as a novolak resin.

[0046]

Embedded image

Where Ar^Two Is a benzene ring, naphthalene
A ring or an anthracene ring. R ^FourIs a hydrogen atom or
Represents a methyl group. R^Five Is a hydrogen atom or carbon number 20
Represents up to alkoxy groups. X¹ Is a single bond or
Containing one or more atoms selected from C, H, N, O, and S
And a divalent linking group having 0 to 20 carbon atoms. k
Represents an integer of 1 to 4.

In the present invention, as the binder polymer,
A homopolymer composed of only the structural unit represented by the general formula (III) may be used, or a copolymer having a structural unit derived from another known monomer may be used together with the specific structural unit. good. The proportion of the structural unit represented by the general formula (III) contained in the copolymer using these is 50
It is preferably from 100 to 100% by weight, and more preferably from 60 to 100% by weight. Further, the weight average molecular weight of the polymer used in the present invention is preferably 5,000 or more, more preferably in the range of 10,000 to 300,000,
The number average molecular weight is preferably at least 1,000, more preferably in the range of 2,000 to 250,000. The polydispersity (weight average molecular weight / number average molecular weight) is preferably 1 or more, and more preferably in the range of 1.1 to 10. These polymers may be any of a random polymer, a block polymer, a graft polymer and the like, but are preferably a random polymer.

Next, novolaks will be described. The novolak resin preferably used in the present invention includes phenol novolak, o-, m-, p- various cresol novolaks, and copolymers thereof, novolaks using phenol substituted with a halogen atom, an alkyl group, and the like. Can be The weight average molecular weight of these novolak resins is preferably at least 1,000, more preferably 2,000.
And a number average molecular weight of preferably 100
0 or more, more preferably 2000 to 15000
Range. The polydispersity is preferably 1 or more, more preferably in the range of 1.1 to 10.

In a preferred embodiment, a polymer having a heterocyclic group having an unsaturated bond in the ring is used as the binder polymer. Here, the term "heterocycle" refers to a ring that contains at least one heteroatom other than carbon among the atoms constituting the ring system. As the hetero atom used, a nitrogen atom, an oxygen atom, a sulfur atom, and a silicon atom are preferable. It is considered that by using a polymer having such a heterocyclic group, the function of the lawn pair present in the present heterocyclic ring facilitates a chemical structural reaction, and a film having good printing durability is formed.

The binder polymers used in the present invention described above may be used alone or as a mixture of two or more. These polymers are added at a ratio of 20 to 95% by weight, preferably 40 to 90% by weight based on the total solid content of the acid crosslinked layer. When the addition amount is less than 20% by weight, the strength of the image portion is insufficient when an image is formed. When the amount exceeds 95% by weight, no image is formed.

In this acid crosslinked layer, (c) described later
By containing an infrared absorbing agent, recording by infrared laser exposure can be performed, and sensitivity to actinic radiation can be improved. In forming the acid crosslinked layer, various additives such as a surfactant can be used in combination for the purpose of improving coating properties and film quality.

Examples of the positive type recording layer include an interaction release system (thermosensitive positive) and an o-quinonediazide compound-containing system. It will be described below in order. <Interaction Canceling System (Thermal Positive)> The interaction canceling system contains (a) a water-insoluble and alkali-water-soluble polymer described below, the (b) specific crosslinking agent, and (c) an infrared absorber described below. .

The polymer compound (a) which can be used in the positive recording layer includes a homopolymer containing an acidic group in the main chain and / or side chain of the polymer, a copolymer thereof, or a mixture thereof. Is included. Among them, the following (1)-
Those having an acidic group described in (6) in the main chain and / or side chain of the polymer are preferable in view of solubility in an alkaline developer and development of dissolution inhibiting ability.

(1) Phenol group (—Ar—OH) (2) Sulfonamide group (—SO ₂ NH—R) (3) Substituted sulfonamide acid group (hereinafter referred to as “active imide group”) SO ₂ NHCOR, -SO ₂ NHSO ₂ R, -CO
NHSO ₂ R] (4) Carboxylic acid group (—CO ₂ H) (5) Sulfonic acid group (—SO ₃ H) (6) Phosphate group (—OPO ₃ H ₂ )

In the above (1) to (6), Ar represents a divalent aryl linking group which may have a substituent, and R represents a hydrocarbon group which may have a substituent. .

Among the alkaline water-soluble polymers having an acidic group selected from the above (1) to (6), among the alkaline water-soluble polymers having (1) a phenol group, (2) a sulfonamide group and (3) an active imide group, A polymer is preferable, and an alkali water-soluble polymer having (1) a phenol group or (2) a sulfonamide group is most preferable in terms of sufficiently securing solubility in an alkaline developer, development latitude, and film strength.

Examples of the alkali water-soluble polymer having an acidic group selected from the above (1) to (6) include the following. (1) Examples of the alkali water-soluble polymer having a phenol group include a condensation polymer of phenol and formaldehyde, a condensation polymer of m-cresol and formaldehyde, a condensation polymer of p-cresol and formaldehyde,
Condensed polymer of m- / p-mixed cresol and formaldehyde, phenol and cresol (m-, p- or m
-/ P- mixture) and a novolak resin such as a condensation polymer of formaldehyde, and a condensation polymer of pyrogallol and acetone. further,
Copolymers obtained by copolymerizing a compound having a phenol group in the side chain can also be used. Alternatively, a copolymer obtained by copolymerizing a compound having a phenol group in a side chain can be used.

Examples of the compound having a phenol group include acrylamide, methacrylamide, acrylate, methacrylate, and hydroxystyrene having a phenol group.

The weight average molecular weight of the alkali water-soluble polymer is from 5.0 × 10 ^{2 to} 2.0 × 10 ⁴ and the number average molecular weight is from 2.0 × 10 ^{2 to} 1.0 × 10 ⁴ . It is preferable from the viewpoint of image forming properties. These polymers may be used alone or in combination of two or more. If combined, see US Pat. No. 4,123,279.
A phenol having an alkyl group having 3 to 8 carbon atoms as a substituent, such as a condensation polymer of t-butylphenol and formaldehyde or a condensation polymer of octylphenol and formaldehyde, as described in the specification of A condensed polymer with formaldehyde, an alkali water-soluble polymer having a phenol structure having an electron-withdrawing group on an aromatic ring described in Japanese Patent Application Laid-Open No. 2000-241972 previously submitted by the present inventors is used in combination. Is also good.

(2) Examples of the alkali water-soluble polymer having a sulfonamide group include a polymer having, as a main component, a minimum structural unit derived from a compound having a sulfonamide group. Examples of the compound as described above include a compound having at least one sulfonamide group in which at least one hydrogen atom is bonded to a nitrogen atom and at least one polymerizable unsaturated group in the molecule. Above all, a low molecular weight compound having an acryloyl group, an allyl group, or a vinyloxy group, and a substituted or monosubstituted aminosulfonyl group or a substituted sulfonylimino group in a molecule is preferable. Compounds.

[0062]

Embedded image

[Where X is¹ , X^Two Are independently-
O- or -NR²⁷Represents-. R^{twenty one}, R^{twenty four}Respectively
Independently a hydrogen atom or -CH_Three Represents R^{twenty two}, R^{twenty five}, R
²⁹, R ³²And R³⁶Each independently has a substituent
An alkylene group having 1 to 12 carbon atoms, cycloalkyl
Represents a len group, an arylene group or an aralkylene group. R
^{twenty three}, R²⁷And R³³Are each independently a hydrogen atom, a substituent
An alkyl group having 1 to 12 carbon atoms which may have
Represents a loalkyl group, an aryl group or an aralkyl group.
Also, R²⁶, R³⁷Each independently has a substituent
C1-C12 alkyl group, cycloalkyl
Represents an aryl group or an aralkyl group. R ²⁸, R³⁰as well as
R³⁴Is independently a hydrogen atom or -CH_Three The table
You. R³¹, R ³⁵Are each independently a single bond or substituted
An alkylene group having 1 to 12 carbon atoms which may have a group,
Cycloalkylene, arylene or aralkylene
Represents a group. Y^Three , Y^Four Are each independently a single bond,
Represents -CO-. ]

Among the compounds represented by the general formulas 1 to 5, in the positive type lithographic printing material of the present invention, m-aminosulfonylphenyl methacrylate, N- (p-aminosulfonylphenyl) methacrylamide, N- (P-Aminosulfonylphenyl) acrylamide and the like can be suitably used.

(3) Examples of the alkali water-soluble polymer having an active imide group include a polymer having, as a main constituent, a minimum structural unit derived from a compound having an active imide group. Examples of such compounds include compounds having at least one active imide group represented by the following structural formula and one or more polymerizable unsaturated groups in the molecule.

[0066]

Embedded image

Specifically, N- (p-toluenesulfonyl) methacrylamide, N- (p-toluenesulfonyl) acrylamide and the like can be suitably used.

(4) Examples of the alkali water-soluble polymer having a carboxylic acid group include, for example, a minimum structural unit derived from a compound having one or more carboxylic acid groups and one or more polymerizable unsaturated groups in the molecule. Examples of the polymer may be a main component. (5) Examples of the alkali-soluble polymer having a sulfonic acid group include, as a main structural unit, a minimum structural unit derived from a compound having one or more sulfonic acid groups and one or more polymerizable unsaturated groups in a molecule. Polymer. (6) The alkaline water-soluble polymer having a phosphate group includes, for example, a minimum constituent unit derived from a compound having at least one phosphate group and at least one polymerizable unsaturated group in the molecule as a main constituent component. The following polymer can be mentioned.

The minimum structural unit having an acidic group selected from the above (1) to (6), which constitutes the alkali water-soluble polymer used for the positive type recording layer, need not be only one kind, but may be the same. It is also possible to use a copolymer obtained by copolymerizing two or more kinds of the minimum structural units having an acidic group or two or more kinds of the minimum structural units having different acidic groups.

The above copolymer is copolymerized (1) to
It is preferred that the compound having an acidic group selected from (6) is contained in the copolymer in an amount of at least 10 mol%, more preferably at least 20 mol%. 10 mol%
If it is less than 3, the developing latitude tends to be insufficiently improved.

[(C) Infrared absorbing agent] In the case where the image recording material of the present invention is used for the purpose of performing recording by heat mode exposure, typically a laser emitting infrared rays,
In addition to the above components, it is necessary to use an infrared absorber. By using the infrared absorbing agent in combination with the image recording material of the present invention, an image forming material whose solubility in an aqueous alkali solution is changed by infrared exposure can be obtained. By using this for the recording layer of a lithographic printing plate precursor, an infrared ray can be obtained. The developing process of the alkali aqueous solution after the laser exposure improves the developability of the exposed portion, the positive type or alkali developability in which the exposed portion becomes a non-image portion region is reduced by exposure to infrared rays, and the exposed portion becomes A negative type image is formed. The infrared absorber used in the present invention is not particularly limited as long as it has a function of absorbing light having a predetermined wavelength and converting the absorbed light into heat, but is generally used for writing. Wavelength of the infrared laser, ie, from 760 nm to 12
Dyes or pigments having an absorption maximum at 00 nm are mentioned. Examples of pigments include commercially available pigment and color index (CI) handbook, “Latest Pigment Handbook” (edited by Japan Pigment Technical Association, 1977), “Latest Pigment Application Technology” (CM
C Publishing, 1986) and "Printing Ink Technology", CMC Publishing, 1984) can be used.

The pigments include black pigment, yellow pigment, orange pigment, brown pigment, red pigment, purple pigment,
Blue pigment, green pigment, fluorescent pigment, metal powder pigment, etc.
Polymer-bound dyes. Specifically, insoluble azo pigments, azo lake pigments, condensation azo pigments, chelate azo pigments, phthalocyanine pigments, anthraquinone pigments,
Perylene and perinone pigments, thioindigo pigments,
Quinacridone pigments, dioxazine pigments, isoindolinone pigments, quinophthalone pigments, dye lake pigments, azine pigments, nitroso pigments, nitro pigments, natural pigments, fluorescent pigments, inorganic pigments, carbon black and the like can be used.

These pigments may be used without being subjected to a surface treatment, or may be used after being subjected to a surface treatment. Methods of surface treatment include a method of surface coating a resin or wax, a method of attaching a surfactant, and a reactive substance (for example, a silane coupling agent, an epoxy compound, or a polyisocyanate).
Can be conceived on the surface of the pigment. The above surface treatment methods are described in "Properties and Applications of Metallic Soap" (Koshobo),
"Printing ink technology" (CMC Publishing, 1984) and "Latest Pigment Application Technology" (CMC Publishing, 1986)
It is described in.

The particle size of the pigment is preferably in the range of 0.01 μm to 10 μm, more preferably in the range of 0.05 μm to 1 μm, and particularly preferably in the range of 0.1 μm to 1 μm.
Is preferably within the range. Pigment particle size 0.01μ
If it is less than m, the dispersion is not preferred in terms of stability in the coating solution for the recording layer, and if it exceeds 10 μm, it is not preferred in terms of the uniformity of the recording layer. As a method for dispersing the pigment, a known dispersion technique used in the production of ink or toner can be used. Dispersers include ultrasonic dispersers, sand mills, attritors, pearl mills, super mills,
Examples include a ball mill, an impeller, a disperser, a KD mill, a colloid mill, a dynatron, a three-roll mill, and a pressure kneader. For details, see “Latest Pigment Application Technology”
(CMC Publishing, 1986).

As the dye, commercially available dyes and known dyes described in literatures (for example, "Dye Handbook" edited by The Society of Synthetic Organic Chemistry, published in 1970) can be used. Specific examples include dyes such as azo dyes, metal complex salt azo dyes, pyrazolone azo dyes, anthraquinone dyes, phthalocyanine dyes, carbonium dyes, quinone imine dyes, methine dyes, cyanine dyes, diimonium dyes, and aminium dyes. In the present invention, among these pigments or dyes, those that absorb infrared light or near-infrared light are particularly preferable because they are suitable for use in lasers that emit infrared light or near-infrared light.

As such a pigment absorbing infrared light or near infrared light, carbon black is preferably used. Dyes that absorb infrared light or near infrared light include, for example, JP-A-58-125246 and JP-A-59-125246.
Cyanine dyes described in JP-A-84356, JP-A-59-202829, JP-A-60-78787, etc.
JP-A-58-173696, JP-A-58-18169
0, methine dyes described in JP-A-58-194595, JP-A-58-112793 and JP-A-58-112793.
Naphthoquinone dyes described in JP-A-224793, JP-A-59-48187, JP-A-59-73996, JP-A-60-52940 and JP-A-60-63744; And squarylium dyes described in British Patent No. 434,875, and dihydroperimidine squarylium dyes described in US Pat. No. 5,380,635.

As a dye, US Pat. No. 5,156,
No. 938 is also preferably used, and substituted arylbenzo (thio) pyrylium salts described in U.S. Pat. No. 3,881,924;
No. 42645 (U.S. Pat. No. 4,327,169);
No. 51, No. 58-220143, No. 59-41363
Nos. 59-84248, 59-84249, 59-146063, and 59-146061 and pyrylium compounds described in JP-A-59-2161.
No. 46, the cyanine dye described in U.S. Pat. No. 4,283,4.
No. 75, pentamethine thiopyrylium salts and the like, and pyrylium compounds disclosed in Japanese Examined Patent Publication Nos. 5-135514 and 5-19702. 178, E
pole III-130, Epollight III-
125, Epollight IV-62A and the like are particularly preferably used.

Another particularly preferred example of the dye is a near-infrared absorbing dye described as formulas (I) and (II) in US Pat. No. 4,756,993. These pigments or dyes are optionally added for the purpose of making the image forming material of the present invention compatible with the heat mode, and when added, the amount of addition is 0.01 to 20% based on the total solid content of the image forming material. weight%
The degree is preferably, and in the case of a dye, particularly preferably 0.5 to 1
0% by weight, particularly preferably 0.1 to 5% by weight in the case of a pigment
At the same rate. If the amount of pigment or dye added is 0.0
If the amount is less than 1% by weight, the effect of the addition is not seen.
Exceeding the weight% is not preferred because it may affect the storage stability of the image forming material.

<O-quinonediazide compound-containing system>
As the quinonediazide compound-containing system, JP-A-5-24
A positive recording layer containing an o-quinonediazide compound as a photosensitive component, described in JP-A-6171 and JP-A-6-230582.

[Other Components] As other components of the image recording material of the present invention, various known components of an image recording material recordable with actinic radiation such as ultraviolet rays and infrared rays can be appropriately selected and used. . In the image forming material of the present invention,
Further, various additives can be added as needed. For example, other onium salts, aromatic sulfone compounds,
It is preferable to add an aromatic sulfonic acid ester compound, a polyfunctional amine compound, or the like, because the function of inhibiting the dissolution of the alkali water-soluble polymer in the developer can be improved.

Examples of the onium salts include diazonium salts, ammonium salts, phosphonium salts, iodonium salts, sulfonium salts, selenonium salts, arsonium salts and the like. The onium salt is preferably added in an amount of 1 to 50% by weight, more preferably 5 to 30% by weight, and particularly preferably 10 to 30% by weight, based on the total solids constituting the image forming material. preferable.

Further, in order to further improve the sensitivity,
Cyclic anhydrides, phenols, and organic acids can be used in combination. As the cyclic acid anhydride, US Pat.
Phthalic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride described in US Pat. No. 5,128;
3,6-Endoxy-Δ4-tetrahydrophthalic anhydride, tetrachlorophthalic anhydride, maleic anhydride, chloromaleic anhydride, α-phenylmaleic anhydride, succinic anhydride, pyromellitic anhydride and the like can be used. Examples of phenols include bisphenol A, p-nitrophenol, p-ethoxyphenol, 2,4,4'-trihydroxybenzophenone, 2,3,4-trihydroxybenzophenone, 4-hydroxybenzophenone,
4,4 ', 4 "-trihydroxytriphenylmethane,
4,4 ', 3 ", 4" -tetrahydroxy-3,5
3 ', 5'-tetramethyltriphenylmethane and the like. Further, as the organic acids, JP-A-60-88
No. 942, JP-A-2-96755 and the like, sulfonic acids, sulfinic acids, alkyl sulfates, phosphonic acids, phosphoric esters, carboxylic acids and the like. The proportion of the above cyclic acid anhydride, phenols and organic acids in the image forming material is,
The content is preferably 0.05 to 20% by weight, more preferably 0.1 to 20% by weight.
It is 1 to 15% by weight, particularly preferably 0.1 to 10% by weight.

Other than these, epoxy compounds,
Vinyl ethers, and further, a crosslinkable compound having an alkali dissolution inhibiting action described in Japanese Patent Application Laid-Open No. 11-160860 previously proposed by the present inventors can be appropriately added according to the purpose.

Further, in the image forming material of the present invention, JP-A Nos. 62-251740 and 3-208514 disclose a method for expanding 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.

In the image forming material of the present invention, a printing-out agent for obtaining a visible image immediately after heating by exposure,
Dyes and pigments as image colorants can be added.
Representative examples of the printing-out agent include a combination of a compound that releases an acid by heating upon exposure (photoacid releasing agent) and an organic dye that can form a salt. In particular,
Combinations of o-naphthoquinonediazide-4-sulfonic acid halogenide and salt-forming organic dyes described in JP-A-50-36209 and JP-A-53-8128, and JP-A-53-36223 and JP-A-53-36223. 54-74728, 6
No. 0-3626, No. 61-143748, No. 61-1
Combinations of trihalomethyl compounds and salt-forming organic dyes described in JP-A-51644 and JP-A-63-58440 can be exemplified. Such trihalomethyl compounds include oxazole-based compounds and triazine-based compounds, both of which have excellent stability over time and give clear print-out images.

As the colorant for the image, other dyes can be used in addition to the above-mentioned salt-forming organic dyes. Suitable dyes, including salt-forming organic dyes, include oil-soluble dyes and basic dyes. 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 Industry Co., Ltd.), Victoria Pure Blue, crystal violet (CI42555), methyl Violet (CI42535), ethyl violet, rhodamine B (CI145170B), malachite green (CI42000), methylene blue (CI5201)
5) and the like. Also, Japanese Patent Application Laid-Open No. 62-2932
The dyes described in JP-B-47 are particularly preferred. These dyes are used in an amount of 0.01 to 1 based on the total solid content of the image forming material.
0% by weight, preferably 0.1 to 3% by weight can be added to the image forming material. Further, a plasticizer may be added to the image forming material of the present invention, if necessary, in order to impart flexibility and the like to the coating film. For example, butylphthalyl, polyethylene glycol, tributyl citrate, diethyl phthalate, dibutyl phthalate, dihexyl phthalate, dioctyl phthalate, tricresyl phosphate, tributyl phosphate, trioctyl phosphate, tetrahydrofurfuryl oleate, acrylic acid or methacrylic acid Oligomers and polymers are used.

A lithographic printing plate precursor is prepared by dissolving a coating solution for a recording layer containing the image forming material of the present invention or a coating solution component for a desired layer such as a protective layer in a solvent and coating the solution on a suitable support. Can be manufactured. As the solvent used herein, 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, dimethoxy Ethane, methyl lactate, ethyl lactate, N, N-dimethylacetamide, N, N-dimethylformamide, tetramethylurea, N-methylpyrrolidone, dimethylsulfoxide, sulfolane, γ-butyrolactone, toluene,
Water and the like can be mentioned, but it is not limited thereto. 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 coating amount (solid content) on the support obtained after coating and drying varies depending on the use, but generally 0.5 to 5.0 g / m ² is preferred for a photosensitive printing plate. As a method of applying, various methods can be used, for example, bar coater coating, spin coating, spray coating, curtain coating, dip coating, air knife coating, blade coating,
Roll coating and the like can be mentioned. As the coating amount decreases, the apparent sensitivity increases, but the film characteristics of the recording layer deteriorate.

In the coating solution for the recording layer using the image recording material of the present invention, a surfactant for improving the coating property, for example, a fluorine-based surfactant described in JP-A-62-170950 is used. Surfactants can be added. The preferred addition amount is 0.01 to 1% by weight, more preferably 0.05 to 0.5% by weight of the whole image forming material.

As the support used in the lithographic printing plate precursor according to the present invention, a dimensionally stable plate-like material is used. For example, paper, plastic (eg, polyethylene, polypropylene, polystyrene, etc.) is laminated. Paper, metal plate (eg, aluminum, zinc, copper, etc.), plastic film (eg, cellulose diacetate, cellulose triacetate, cellulose propionate, cellulose butyrate, cellulose acetate butyrate, cellulose nitrate, polyethylene terephthalate, polyethylene, polystyrene, Polypropylene, polycarbonate, polyvinyl acetal, etc.),
Examples include paper or plastic film on which a metal is laminated or vapor-deposited as described above.

As the support used in the lithographic printing plate precursor of the present invention, a polyester film or an aluminum plate is preferable, and among them, an aluminum plate having good dimensional stability and relatively low cost 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 the aluminum alloy include silicon, iron, manganese, copper, magnesium, chromium, zinc, bismuth, nickel, and titanium. The content of the foreign element in the alloy is at most 10% by weight or less. Particularly preferred aluminum 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 approximately 0.1 mm to 0.6 mm, preferably 0.15 m.
m to 0.4 mm, particularly preferably 0.2 mm to 0.3 m
m.

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, as disclosed in JP-A-54-63902, a method in which both are combined can be used. 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 for forming a porous oxide film can be used, and 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.

Since the anodizing treatment conditions vary depending on the electrolyte used, they cannot be specified unconditionally. Generally, however, 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 4,153,46.
For example, a method of treating with polyvinyl phosphonic acid as disclosed in JP-A Nos. 1 and 4,689,272 is used.

The lithographic printing plate precursor according to the invention has a recording layer containing the image-forming material according to the invention provided on a support. An undercoat layer may be provided between the recording layers as needed. Various organic compounds are used as the undercoat layer component,
For example, carboxymethylcellulose, dextrin,
Gum arabic, phosphonic acids having an amino group such as 2-aminoethylphosphonic acid, phenylphosphonic acid, naphthylphosphonic acid, alkylphosphonic acid, glycerophosphonic acid, methylenediphosphonic acid and ethylenediphosphonic which may have a substituent Organic phosphonic acids such as acids, phenylphosphoric acid optionally having a substituent, naphthylphosphoric acid, organic phosphoric acid such as alkylphosphoric acid and glycerophosphoric acid, phenylphosphinic acid optionally having a substituent, naphthylphosphinic acid, Selected from organic phosphinic acids such as alkylphosphinic acid and glycerophosphinic acid, amino acids such as glycine and β-alanine, and hydrochlorides of amines having a hydroxy group such as hydrochloride of triethanolamine. You may use it. Also,
A polymer compound containing a unit that interacts with an alumina layer and a unit that interacts with a hydrophilic treatment layer described in JP-A-11-1099641 can also be suitably used.

The lithographic printing plate precursor prepared as described above is usually subjected to image exposure and development to form an image. Among the actinic radiation used for the image exposure, the light source of the light beam includes, for example, a mercury lamp, a metal halide lamp, a xenon lamp, a chemical lamp, a carbon arc lamp and the like. Examples of the radiation include an electron beam, an X-ray, an ion beam, and a far-infrared ray. G-line, i-line, Deep-UV
Light, high-density energy beams (laser beams) are also used. Examples of the laser beam include a helium / neon laser, an argon laser, a krypton laser, a helium / cadmium laser, a KrF excimer laser, a solid laser, and a semiconductor laser. When the image forming material of the present invention is used as a material for a heat mode, a solid-state laser that emits infrared light having a wavelength of 720 to 1200 nm, a semiconductor laser, or the like is preferably used.
Solid-state lasers and semiconductor lasers, which are light sources having emission wavelengths in the near infrared to infrared region, are particularly preferred.

In the present invention, the developing treatment may be performed immediately after the exposure, or a heat treatment (post-heating) may be performed between the exposure step and the developing step. When performing a heat treatment, the conditions are 40 ° C to 200 ° C, preferably 50 to 180 ° C,
More preferably, in the range of 60 to 150 ° C., for 2 seconds to 1 hour.
It is preferably performed for 0 minutes, preferably for 5 seconds to 5 minutes.
As a heating method, various conventionally known methods can be used. For example, a method of heating while contacting the recording material with a panel heater or a ceramic heater, and a non-contact heating method with a lamp or hot air are used. By this heat treatment, the laser energy required for recording at the time of laser irradiation can be reduced.

As the developer and replenisher for the lithographic printing plate precursor according to the invention, conventionally known aqueous alkali 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 alkali agents, particularly preferred developers are aqueous silicate solutions such as sodium silicate and potassium silicate. The reason is silicon oxide SiO ₂ and alkali metal oxides are components of the silicate
This is because developability can be adjusted by the ratio and concentration of M ₂ O. For example, JP-A-54-62004 discloses
The alkali metal silicate described in JP-B-57-7427 is effectively used.

Further, when 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 PS plates can be processed without replacing the developing solution in the developing tank for a long time by adding to the developing solution. This replenishment method is also preferably applied in the present invention. To the developing solution and the replenishing solution, various surfactants and organic solvents can be added as necessary for the purpose of promoting or suppressing the developing property, dispersing the developing residue and increasing the ink affinity of the printing plate image area. Preferred surfactants include anionic, cationic, nonionic and amphoteric surfactants. Further, the developing solution and the replenisher may contain, if necessary, a reducing agent such as a sodium salt or a potassium salt of an inorganic acid such as hydroquinone, resorcinol, sulfurous acid, and bisulfite, and an organic carboxylic acid, an antifoaming agent, and a water softener. Can 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. As a post-process when the image recording material of the present invention is used as a printing plate, these processes can be used in various combinations.

In recent years, in the plate making and printing industry, automatic developing machines for printing plates have been widely used in order to rationalize and standardize plate making operations. This automatic developing machine generally comprises a developing section and a post-processing section, and comprises a device for transporting a printing plate, each processing solution tank and a spray device, and while pumping the exposed printing plate horizontally, each pumped by a pump. The developing process is performed by spraying a processing liquid from a spray nozzle. Recently, a method has been known in which a printing plate is immersed and conveyed by a submerged guide roll or the like in a processing liquid tank filled with a processing liquid to perform processing. 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 photosensitive lithographic printing plate precursor using the image forming material of the present invention will be described. If the lithographic printing plate obtained by image exposure, development, washing and / or rinsing and / or gumming has unnecessary image portions (for example, film edge marks of the original film), unnecessary portions are unnecessary. Erasing of the image portion is performed. Such erasing is preferably performed by applying an erasing liquid as described in, for example, Japanese Patent Publication No. 2-129393 to an unnecessary image portion, leaving the same for a predetermined period of time, and then rinsing with water. A method described in JP-A-59-174842, in which active light guided by an optical fiber is applied to an unnecessary image portion and then developed, can be used.

The lithographic printing plate obtained as described above can be subjected to a printing step after applying a desensitized gum if desired. Is subjected to a burning process. When the lithographic printing plate is subjected to a burning process, before the burning process, Japanese Patent Publication Nos. 61-2518 and 55-28062,
It is preferable to treat with a surface-regulating liquid as described in JP-A Nos. 62-31859 and 61-159655. As the method, a method of applying the printing solution on a lithographic printing plate with a sponge or absorbent cotton impregnated with the surface conditioning solution, or immersing the printing plate in a vat filled with the surface conditioning solution, Application by an automatic coater is applied. Further, it is more preferable to make the application amount uniform with a squeegee or a squeegee roller after the application.

The coating amount of the 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 burned (for example, a burning processor sold by Fuji Photo Film Co., Ltd .: "BP-130").
0 "). The heating temperature and time in this case depend on the type of the component forming the image,
The temperature is preferably in the range of 180 to 300 ° C for 1 to 20 minutes.

The burn-processed lithographic printing plate can be subjected to a conventional treatment such as washing with water or gumming if necessary. When a liquid is used, a so-called desensitizing treatment such as gumming can be omitted. The lithographic printing plate obtained by such a process is applied to an offset printing machine or the like and used for printing a large number of sheets.

[0104]

EXAMPLES The present invention will be described below with reference to examples, but the scope of the present invention is not limited to these examples. (Examples 1 to 3: Examples of positive type image forming materials) [Preparation of substrate] An aluminum plate (material 1050) having a thickness of 0.3 mm was washed with trichlorethylene and degreased, and then a nylon brush and 400 mesh pumice-water were used. The surface was grained with the suspension and washed well with water. This plate was etched by immersing it in a 25% aqueous solution of sodium hydroxide at 45 ° C. for 9 seconds, washed with water, further immersed in 20% nitric acid for 20 seconds, and washed with water. At this time, the etching amount of the grained surface was about 3 g / m ² . Then this board is 7%
At a current density of 15A / dm ² sulfuric acid as electrolyte 3 g / m
^After the DC anodic oxide coating of No. ² was provided, the coating was washed with water, dried, and further applied with the following undercoat liquid, and the coating was dried at 90 ° C. for 1 minute. The coating amount of the dried coating film was 10 mg / m ² .
Further, the substrate was treated with a 2.5% by weight aqueous solution of sodium silicate at 30 ° C. for 10 seconds, an undercoat liquid described below was applied, and the coating film was dried at 80 ° C. for 15 seconds to obtain a substrate. The coating amount of the coating film after drying is 1
It was 5 mg / m ² . -Undercoating liquid--The following compound: 0.3 g-Methanol-100 g-Water---・ ・ ・ ・ ・ ・ ・ 1g

[0105]

Embedded image

The following photosensitive layer coating solution 1 was applied to the obtained substrate so that the coating amount was 1.6 g / m ² to obtain a lithographic printing plate precursor. -Photosensitive layer coating solution 1-m, p-cresol novolak (m / p ratio = 6/4, weight average molecular weight 3,500, unreacted cresol 0.5% by weight) 0.427 g-JP-A-11-288093 Specific copolymer 1 2.37 g ・ Specific crosslinking agent described in Table 1 0.05 g ・ Cyanine dye A (the following structure) 0.155 g ・ 2-Methoxy-4- (N-phenylamino) benzene ・ Diazonium hexa Fluorophosphate 0.03 g ・ Tetrahydrophthalic anhydride 0.19 g ・ Ethyl violet counter ion converted to 6-hydroxy-β-naphthalenesulfonic acid 0.05 g ・ Fluorinated surfactant (MegaFac F176PF, Dainippon Ink and Chemicals, Inc.) Industrial Co., Ltd.) 0.035 g ・ Fluorinated surfactant (Megafac MCF-312, Dainippon Ink) 0.05 g, paratoluenesulfonic acid 0.008 g, bis-p-hydroxyphenylsulfone 0.063 g, n-dodecyl stearylate 0.06 g, γ-butyrolactone 13 g, methyl ethyl ketone 24 g, 1-methoxy -2-propanol 11g

[0107]

[Table 1]

[0108]

Embedded image

(Comparative Examples 1 and 2) A lithographic printing plate precursor was prepared in the same manner as in Example 1 except that the photosensitive layer coating liquid 1 was used without adding the specific crosslinking agent according to the present invention. And Comparative Example 1. Further, in the same manner as in Example 1 except that in the photosensitive layer coating solution 1, a product obtained by adding Cymel 300 (hexamethylmelamine) manufactured by Mitsui Cytec as a crosslinking agent instead of the specific crosslinking agent according to the present invention was used. A lithographic printing plate precursor was prepared as Comparative Example 2.

[Performance Evaluation of Lithographic Printing Plate] The lithographic printing plate precursors of Examples 1 to 3 and Comparative Examples 1 and 2 prepared as described above were evaluated for performance according to the following criteria. The obtained lithographic printing plate precursors of the present invention 1 to 3 and Comparative Examples 1 and 2 were used in a Trendsetter manufactured by Creo.
The test pattern was imaged (exposed) under the conditions of a beam intensity of 9 w and a drum rotation speed of 150 rpm. First, the lithographic printing plate precursor exposed under the above conditions is
Fuji Photo Film Co., Ltd. supplied with Fuji Photo Film Co., Ltd. developer DT-1 (diluted 1: 9) and Fuji Photo Film Co., Ltd. Finisher FP2W (diluted 1: 1). Using a PS processor 900H, the liquid temperature was maintained at 30 ° C., and development was performed for a development time of 12 seconds.
In each of the obtained lithographic printing plates, a good image was formed without causing stain on the non-image portion. Next, the plate surface was treated with a solution obtained by diluting gum GU-7 manufactured by Fuji Photo Film Co., Ltd. with water two-fold, left for one day, and then printed with a Heidel KOR-D machine. The number of sheets on which a normal printed matter was obtained by printing was counted, and the printing durability was evaluated. The results are shown in Table 1 above.

Further, in order to confirm the improvement in printing durability due to heating after exposure, the plate surface was wiped with a burning surface conditioning liquid BC-3 manufactured by Fuji Photo Film Co., Ltd., and a burning device BP-1 was used.
Using 300, treatment was performed at 200 ° C. for 3 minutes. Then
The plate surface was treated with a solution obtained by diluting gum GU-7 manufactured by Fuji Photo Film Co., Ltd. with water two-fold, and printing was performed using a Heidel KOR-D machine in the same manner as a plate without heat treatment. The number of normal printed matter obtained by printing was counted. The results are shown in Table 1 above. Further, for the purpose of examining the storage stability, the lithographic printing plate precursor before exposure was subjected to high humidity conditions (75% RH, 45% RH).
C.) for 3 days. Immediately after the preparation, the lithographic printing plate precursor exposed and developed was processed in the same manner as described above, and the clear sensitivity was determined in the same manner. Table 1 shows the results.

As is clear from Table 1, the lithographic printing plate precursor using the image recording material of the present invention as a recording layer has good storage stability and has a long printing life by being subjected to a heat treatment after exposure. It was confirmed that the property was significantly improved.

(Examples 4 to 6: Examples of negative-type image forming materials) Substrates were prepared in the same manner as in Example 1 except that the undercoat liquid of the substrate used in Example 1 was changed to the following composition. The following photosensitive layer coating solution 2 was applied to the substrate and dried at 100 ° C. for 1 minute to obtain a negative type lithographic printing plate precursor. The coated amount of the photosensitive layer after drying was 1.3 g / m ² . -Undercoat liquid- β-alanine 0.1 g Phenylphosphonic acid 0.05 g Methanol ... 40 g water ... 60 g

-Photosensitive layer coating solution 2-A diazonium salt represented by the general formula (1) used in Example 1 described in JP-A-11-352679: 0.15 g・ Infrared absorber ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ 0.1g (IR-768 perchlorate, manufactured by Sigma-Aldrich Japan) ・ Poly-P-hydroxystyrene resin 1.5 g (MARUKA LYNCUR MS4P manufactured by Maruzen Petrochemical Co., Ltd.) Specific cross-linking agents listed in Table 2 ... 0.25g-Crosslinking agent B (the following structural formula) ... 0.25g-Fluorosurfactant ... 0.03g (MegaFac F-177, Dainippon Ink and Chemicals, Inc.) (Manufactured by Kogyo Co., Ltd.)-Methyl ethyl ketone-15 g-1-methoxy-2-propanol- 10 g ・ Methyl alcohol 5 g

[0115]

Embedded image

The negative type lithographic printing plate precursor obtained was exposed in the same manner as in Example 1. After the exposure, a heat treatment was performed for 1 minute in a 140 ° C. oven, and a developing solution manufactured by Fuji Photo Film Co., Ltd., DP-4 (1: 8), and a rinsing solution FR-3 (1:
When processed through an automatic processor equipped with 7), a good negative image was obtained.

Comparative Example 3 In the photosensitive layer coating solution 2 used in Examples 4 to 6, Cymel 300 (hexamethylmelamine) manufactured by Mitsui Cytec Co., Ltd. was added in place of the specific crosslinking agent according to the present invention. A lithographic printing plate precursor was prepared in the same manner as in Example 4 except that the above was used, and Comparative Example 2 was used.

After the obtained lithographic printing plate precursor was exposed,
After a heat treatment in an oven at 0 ° C. for 1 minute, a developing solution manufactured by Fuji Photo Film Co., Ltd., DP-4 (1: 8), rinsing solution F
When processed through an automatic developing machine charged with R-3 (1: 7), good negative images were obtained for all lithographic printing plate precursors. Exposure conditions are as follows:
And the output was changed stepwise from 3 to 12 W to determine the clear sensitivity.

Next, gum G manufactured by Fuji Photo Film Co., Ltd.
The plate surface was treated with a liquid obtained by diluting U-7 twice with water, left for one day, and then printed with a Heidel KOR-D machine. The number of sheets on which a normal printed matter was obtained by printing was counted, and the printing durability was evaluated. The results are shown in Table 2 above. Further, for the purpose of examining the storage stability, the lithographic printing plate precursor before exposure was subjected to high humidity conditions (7.
(5% RH, 45 ° C.) for 3 days. Immediately after the preparation, the lithographic printing plate precursor exposed and developed was processed in the same manner as above, and the clear sensitivity was similarly determined. Table 2 shows the results.

[0120]

[Table 2]

As is evident from Table 2, even when a negative type image forming material was used, the lithographic printing plate precursor according to the present invention had a higher printing durability than the one using a known crosslinking agent. And storage stability was found to be good.

[0122]

The image-forming material of the present invention is recordable with an infrared laser and is excellent in storage stability, image-forming properties and strength of the obtained image. In addition, a lithographic printing plate precursor using this image forming material is capable of directly making a plate with an infrared laser, and has effects of high sensitivity, storage stability, excellent image forming properties, and good printing durability. .

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2H025 AA00 AA12 AA13 AB03 AC08 AD01 AD03 BE00 CB17 CB29 CB52 CC20 FA03 FA12 FA17 FA29 2H096 AA00 AA07 AA08 BA01 BA09 BA16 BA20 EA04 FA01 GA08 HA01 JA04

Claims (3)

[Claims] 1. Irradiation with actinic radiation, comprising (a) a polymer compound that is insoluble in water and soluble in an aqueous alkali solution, and (b) a crosslinking agent represented by the following general formula (1): The image forming material is characterized in that the solubility in an aqueous alkaline solution is changed by the method. Embedded image In the formula, n represents an integer of 1 to 3, m represents an integer of 1 or more, and n
And m is 2 or more. A ¹ is a monovalent organic group, A ² is 2
A valent organic group, Z represents an m-valent organic group, and X represents a divalent organic group selected from the following. Embedded image 2. A polymer compound which is insoluble in water and soluble in an aqueous alkaline solution, and
A crosslinking agent represented by: and (c) an infrared absorber,
A heat mode-compatible image-forming material, wherein the solubility in an aqueous alkali solution is changed by infrared exposure. Embedded image In the formula, n represents an integer of 1 to 3, m represents an integer of 0 to 8,
¹ represents a monovalent organic group, A ² represents a divalent organic group, Z represents an m-valent organic group, and X represents a divalent organic group selected from the following. Embedded image 3. The method according to claim 1, wherein the support is provided on a support.
A lithographic printing plate precursor comprising a recording layer comprising the image forming material described in 1 above.