JP2004171029A - Photosensitive image forming material for infrared laser - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a positive type image forming material for an infrared laser having improved image forming characteristics of a recording layer, excellent printing durability, and favorable stability of the sensitivity to the density of a developer. <P>SOLUTION: On a supporting body, (A) a layer including 50 percentage by weight or more of copolymer which includes at least one of the monomers (1) to (12) below as a copolymerization ingredient, and (B) a layer including 50 percentage by weight or more of a novolak resin are laminated sequentially. Monomers are chosen from a group composed of (1) acrylate ester and methacrylate ester having aliphatic hydroxyl group, (2) alkyl acrylate, (3) alkyl methacrylate, (4) acrylamide and methacrylamide, (5) vinyl ether, (6) vinyl ester, (7) styrene, (8) vinyl ketone, (9) olefin, (10) N-vinylpyrrolidone, N-vinylcarbozole, 4-vinylpyridine, acrylonitrile, and methacrylonitrile, (11) unsaturated imide, and (12) unsaturated carboxylic acid. <P>COPYRIGHT: (C)2004,JPO

Description

  The present invention relates to an image forming material that can be used as an offset printing master, and more particularly to a photosensitive image forming material for an infrared laser for so-called direct plate making that can be directly made from a digital signal of a computer or the like.

In recent years, a system for directly making a plate from digital data of a computer has attracted attention, and various techniques have been developed.
In particular, the development of lasers has been remarkable in recent years. Especially, solid-state lasers and semiconductor lasers with light emitting regions from near infrared to infrared have become readily available as high-power and small-sized lasers. It is very useful as an exposure light source for plate making.

In a conventionally known positive type lithographic printing plate material for infrared laser for direct plate making, an alkaline aqueous solution-soluble resin having a phenolic hydroxyl group such as a novolak resin is used. For example, there has been proposed an image forming material in which a substance that absorbs light and generates heat, various onium salts, quinonediazide compounds, and the like are added to an alkali aqueous solution-soluble resin having a phenolic hydroxyl group such as a novolak resin (for example, , See Patent Document 1). In these image forming materials, onium salts, quinonediazide compounds, etc. act as dissolution inhibitors for aqueous alkali-soluble resins in the image area, and in the non-image area, they are decomposed by heat and no longer exhibit dissolution inhibiting ability, and are removed by development. To be able to form an image.
In such an image forming material, since onium salts, quinonediazide compounds, and the like have a light absorption region (350 to 500 nm) in the visible region, there is an inconvenience that the place of handling is restricted to yellow wrinkles.
Furthermore, onium salts, quinonediazide compounds, etc. are not necessarily compatible with alkaline aqueous solution-soluble polymer compounds or substances that absorb light and generate heat, and it is difficult to prepare a uniform coating solution. Therefore, there is a problem that it is difficult to obtain a stable image forming material.

In addition, there is an example in which no photosensitive compound is used and image formation is performed with a novolak resin or the like (see, for example, Patent Document 2). However, the novolak resin itself has low solvent resistance, and printing durability is improved by using a cleaner or the like. There have been problems such as deterioration in properties and inability to print with UV ink. Further, when a novolak resin is used without using a photosensitive compound, the development latitude is extremely poor.
JP-A-7-285275 Japanese Patent Publication No.46-27919

  Accordingly, the object of the present invention is to improve the low image formability of a recording layer using an aqueous alkali-soluble polymer compound, there is no restriction on the place of handling, the printing durability is excellent, and the sensitivity to the developer concentration. It is to provide an image forming material for an infrared laser for direct plate making having a good stability, that is, a development latitude.

  As a result of intensive studies, the present inventors can use even under white light by forming a specific layer structure using an alkaline water-soluble polymer compound, and the development latitude is greatly improved. The inventors have found that a photosensitive image forming material can be obtained, and have completed the present invention.

That is, the photosensitive image forming material for infrared laser of the present invention comprises (A) 50% by weight of a copolymer containing at least one selected from the group consisting of the following monomers (1) to (12) as a copolymerization component. A layer containing the above (hereinafter, this layer is appropriately referred to as (A) layer) and (B) a layer containing 50% by weight or more of the novolak resin (hereinafter, this layer is appropriately referred to as (B) layer). Are sequentially stacked.
(1) Acrylic acid ester and methacrylic acid ester having an aliphatic hydroxyl group,
(2) alkyl acrylate,
(3) alkyl methacrylate,
(4) Acrylamide and methacrylamide,
(5) vinyl ethers,
(6) vinyl esters,
(7) Styrenes,
(8) vinyl ketones,
(9) olefins,
(10) N-vinylpyrrolidone, N-vinylcarbazole, 4-vinylpyridine, acrylonitrile and methacrylonitrile,
(11) unsaturated imide,
(12) Unsaturated carboxylic acid.

  The layer (A) further includes a monomer having a sulfonamide group in which at least one hydrogen atom is bonded to a nitrogen atom in one molecule of the following monomer (a-1), (a-2) one molecule Among them, a monomer having an active imino group represented by the following formula, (a-3) a monomer selected from acrylamide having a phenolic hydroxyl group, methacrylamide, acrylic ester, methacrylic ester, and hydroxystyrene It is preferable that a copolymer containing 10 mol% or more as at least one copolymer component is contained, and at least the layer (B) contains a compound that absorbs light and generates heat.

In the present invention, the photosensitive layer has a two-layer structure, and on the side close to the support, (A) a specific monomer selected from the above (1) to (12), for example, an acrylate ester having an aliphatic hydroxyl group and methacryl At least one selected from acid esters, alkyl acrylates, acrylamides and methacrylamides, unsaturated imides, unsaturated carboxylic acids and the like as a copolymerization component, and (a-1) on one molecule, on a nitrogen atom A monomer having a sulfonamide group to which at least one hydrogen atom is bonded (hereinafter referred to as a monomer having a sulfonamide group as appropriate), (a-2) an active imino group represented by the above formula in one molecule; Monomer (hereinafter, appropriately referred to as a monomer having an imino group), (a-3) acrylamide having a phenolic hydroxyl group, Copolymers containing at least 10 mol% as a copolymerization component of at least one monomer selected from acrylamide, acrylic acid ester, methacrylic acid ester, and hydroxystyrene (hereinafter appropriately referred to as a monomer having a phenolic hydroxyl group). By forming a layer containing 50% by weight or more of the polymer, an intermediate layer excellent in printing durability and solvent resistance is formed.
Further, a layer containing 50% by weight or more of (B) a novolak resin which is an aqueous alkaline solution-soluble resin having a phenolic hydroxyl group is formed thereon, and this layer contains a compound that absorbs light and generates heat. The aqueous alkali-soluble resin typified by this novolak resin has a strong interaction with a compound that absorbs light and generates heat, has a high sensitivity during image formation by exposure, and has a high effect of suppressing development in unexposed areas. Wide development latitude can be realized.

  Also, in the vicinity of the support, heat generated by the compound that absorbs light and generates heat is dispersed into the support having high thermal conductivity before the temperature of the photosensitive layer in the exposed portion rises to a region sufficient to cause a reaction. However, in the image forming material of the present invention, since the (A) layer corresponding to the above-mentioned intermediate layer exists between the (B) layer and the support, (B) ) Since the heat generated by the compound that absorbs light in the layer and generates heat can be efficiently used for development without diffusing to the support, the sensitivity and development latitude are remarkably improved.

  In the present invention, by adopting the two-layer structure as the photosensitive layer as described above, good image formation is achieved by the interaction between the aqueous alkali-soluble resin in the layer (B) and the compound that absorbs light and generates heat. It becomes possible. This makes it unnecessary to add compounds that have a light absorption region (350 to 500 nm) in the visible region, such as onium salts and quinonediazide compounds. There is no inconvenience. Further, since it is possible to form an image without using a thermal decomposition reaction such as an onium salt or a quinonediazide compound, heat is efficiently used for image formation, and the development latitude is remarkably improved.

  According to the photosensitive image forming material for an infrared laser of the present invention, the low image forming property of the recording layer using the alkaline aqueous solution-soluble polymer compound is improved, the handling place is not limited, and the concentration of the developing solution is not affected. There is an effect that the stability of the sensitivity, that is, the development latitude is good and the image forming material for direct plate making having excellent printing durability is sensitive and can be suitably used.

The present invention will be described in detail below.
As the copolymerization component of the alkaline aqueous solution-soluble polymer compound used for forming the layer (A) in the present invention, for example, monomers listed in the following (1) to (12) can be used.
(1) Acrylic acid esters and methacrylic acid esters having an aliphatic hydroxyl group such as 2-hydroxyethyl acrylate or 2-hydroxyethyl methacrylate.
(2) Methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, amyl acrylate, hexyl acrylate, octyl acrylate, benzyl acrylate, 2-chloroethyl acrylate, glycidyl acrylate, N-dimethylaminoethyl Alkyl acrylates such as acrylates;
(3) Methyl methacrylate, ethyl methacrylate, propyl methacrylate, butyl methacrylate, amyl methacrylate, hexyl methacrylate, cyclohexyl methacrylate, benzyl methacrylate, 2-chloroethyl methacrylate, glycidyl methacrylate, N-dimethylaminoethyl Alkyl methacrylate such as methacrylate.
(4) Acrylamide, methacrylamide, N-methylol acrylamide, N-ethyl acrylamide, N-hexyl methacrylamide, N-cyclohexyl acrylamide, N-hydroxyethyl acrylamide, N-phenyl acrylamide, N-nitrophenyl acrylamide, N-ethyl- Acrylamide or methacrylamide such as N-phenylacrylamide.
(5) Vinyl ethers such as ethyl vinyl ether, 2-chloroethyl vinyl ether, hydroxyethyl vinyl ether, propyl vinyl ether, butyl vinyl ether, octyl vinyl ether, and phenyl vinyl ether.

(6) Vinyl esters such as vinyl acetate, vinyl chloroacetate, vinyl butyrate and vinyl benzoate.
(7) Styrenes such as styrene, α-methylstyrene, methylstyrene, and chloromethylstyrene.
(8) Vinyl ketones such as methyl vinyl ketone, ethyl vinyl ketone, propyl vinyl ketone, and phenyl vinyl ketone.
(9) Olefins such as ethylene, propylene, isobutylene, butadiene and isoprene.
(10) N-vinylpyrrolidone, N-vinylcarbazole, 4-vinylpyridine, acrylonitrile, methacrylonitrile and the like.
(11) Unsaturated imides such as maleimide, N-acryloylacrylamide, N-acetylmethacrylamide, N-propionylmethacrylamide, N- (p-chlorobenzoyl) methacrylamide.
(12) Unsaturated carboxylic acids such as acrylic acid, methacrylic acid, maleic anhydride and itaconic acid.

  In the present invention, the (A) alkaline aqueous solution-soluble polymer compound used for forming the layer further includes (a-1) a monomer having a sulfonamide group, (a-2) a monomer having an active imino group, (a -3) It contains 10 mol% or more of at least one of monomers having a phenolic hydroxyl group as a copolymerization component.

(A-1) As a monomer having a sulfonamide group, one molecule is a low molecule having at least one sulfonamide group in which at least one hydrogen atom is bonded on a nitrogen atom and one or more polymerizable unsaturated bonds. Examples thereof include monomers composed of compounds.
Among these, a low molecular compound having an acryloyl group, an allyl group, or a vinyloxy group, and a substituted or monosubstituted aminosulfonyl group or a substituted sulfonylimino group is preferable.
Examples of such compounds include compounds represented by the following general formulas (I) to (V).

In the formula, X ¹ and X ² each represent —O— or —NR ⁷ —. R ¹ and R ⁴ each represent a hydrogen atom or —CH ₃ . R ² , R ⁵ , R ⁹ , R ¹² and R ¹⁶ each represents an optionally substituted alkylene group having 1 to 12 carbon atoms, a cycloalkylene group, an arylene group or an aralkylene group. R < ³ >, R < ⁷ >, R <^13> shows a hydrogen atom and the C1-C12 alkyl group, cycloalkyl group, aryl group, or aralkyl group which may each have a substituent. R ⁶ and R ¹⁷ each represent a C 1-12 alkyl group, cycloalkyl group, aryl group, or aralkyl group that may have a substituent. R ^8, R ^10, R ¹⁴ represents a hydrogen atom or -CH _3. R ¹¹ and R ¹⁵ each represents a C 1-12 alkylene group, cycloalkylene group, arylene group or aralkylene group which may have a single bond or a substituent. Y ¹ and Y ² each represents a single bond or —CO—.

  Specifically, m-aminosulfonylphenyl methacrylate, N- (p-aminosulfonylphenyl) methacrylamide, N- (p-aminosulfonylphenyl) acrylamide and the like can be preferably used.

  (A-2) As a monomer having an active imino group, a monomer comprising an active imino group represented by the following formula and a low molecular compound each having one or more polymerizable unsaturated bonds in one molecule is used. Can be mentioned.

  As such a compound, specifically, N- (p-toluenesulfonyl) methacrylamide, N- (p-toluenesulfonyl) acrylamide and the like can be preferably used.

The monomer corresponding to (a-3) is a monomer composed of acrylamide, methacrylamide, acrylic ester, methacrylic ester, or hydroxystyrene each having a phenolic hydroxyl group.
Specific examples of such compounds include N- (4-hydroxyphenyl) acrylamide, N- (4-hydroxyphenyl) methacrylamide, o-hydroxyphenyl acrylate, m-hydroxyphenyl acrylate, and p-hydroxyphenyl acrylate. O-hydroxyphenyl methacrylate, m-hydroxyphenyl methacrylate, p-hydroxyphenyl methacrylate, o-hydroxystyrene, m-hydroxystyrene, p-hydroxystyrene and the like can be suitably used.

  The alkaline water-soluble copolymer that can be used in the layer (A) formed adjacent to the support in the photosensitive image forming material of the present invention is at least one of the above (a-1) to (a-3). Is required as a copolymerization component, and more preferably contains 20 mol% or more. If the copolymerization component is less than 10 mol%, the sensitivity decreases because of low solubility in an alkaline developer even after exposure, and the effect of improving printing durability and sensitivity, which are advantages when using this copolymerization component, is insufficient. It becomes.

  Further, this copolymer may contain other copolymerization components other than the monomers (a-1) to (a-3) and a monomer having a phenolic hydroxyl group described later.

  In the present invention, the copolymer contained in the layer (A) preferably has a weight average molecular weight of 2000 or more and a number average molecular weight of 500 or more. More preferably, the weight average molecular weight is 5,000 to 300,000, the number average molecular weight is 800 to 250,000, and the dispersity (weight average molecular weight / number average molecular weight) is 1.1 to 10.

  The copolymers contained in these (A) layers may be used alone or in combination of two or more, and in the total solids content of the (A) layer, 50% by weight or more, preferably 55 It is used in an addition amount of not less than wt%. When the added amount of the copolymer is less than 50% by weight, the printing durability of the image forming material is deteriorated.

  In the layer (A), in addition to the copolymer, for example, a polymer compound having a phenolic hydroxyl group, specifically, phenol formaldehyde resin, m-cresol formaldehyde resin, p-cresol formaldehyde resin, m- / p -A novolak resin such as mixed cresol formaldehyde resin, phenol / cresol (which may be either m-, p-, or m- / p-mixed) mixed formaldehyde resin or pyrogallol acetone resin may be contained.

  Furthermore, as described in US Pat. No. 4,123,279, a condensate of phenol and formaldehyde having an alkyl group having 3 to 8 carbon atoms as a substituent, such as t-butylphenol formaldehyde resin and octylphenol formaldehyde resin. May be used in combination. Such resins may be used alone or in combination of two or more.

In addition to the copolymer, various additives can be added to the composition constituting the layer (A) as necessary. For example, a substance that is thermally decomposable, such as an onium salt, an o-quinonediazide compound, an aromatic sulfone compound, and an aromatic sulfonic acid ester compound, and that substantially reduces the solubility of the alkaline water-soluble polymer compound without being decomposed. Use in combination is preferable in terms of improving the dissolution inhibition of the image area in the developer.
Examples of onium salts include diazonium salts, ammonium salts, phosphonium salts, iodonium salts, sulfonium salts, selenonium salts, and arsonium salts.
In the present invention, a diazonium salt is particularly preferable. Particularly suitable diazonium salts include those described in JP-A-5-158230.

Suitable quinonediazides include o-quinonediazide compounds.
The o-quinonediazide compound used in the present invention is a compound having at least one o-quinonediazide group, which increases alkali solubility by thermal decomposition, and compounds having various structures can be used. That is, o-quinonediazide helps the solubility of the sensitive material system by both the effect of losing the ability to suppress the dissolution of the binder due to thermal decomposition and the change of o-quinonediazide itself into an alkali-soluble substance. Examples of the o-quinonediazide compound used in the present invention include J. Although compounds described in pages 339 to 352 of “Light-Sensitive Systems” by Korser can be used, they are particularly reacted with various aromatic polyhydroxy compounds or aromatic amino compounds. -Sulphonic esters or sulphonic amides of quinonediazides are preferred. Further, benzoquinone (1,2) -diazide sulfonic acid chloride or naphthoquinone- (1,2) -diazide-5-sulfonic acid chloride and pyrogallol-acetone resin as described in JP-B-43-28403 Esters of benzoquinone- (1,2) -diazidosulfonic acid chloride or naphthoquinone- (1,2) -diazido-5-sulfonic acid chloride and phenol described in US Pat. Nos. 3,046,120 and 3,188,210 Esters with formaldehyde resins are also preferably used.

  Further, an ester of naphthoquinone- (1,2) -diazido-4-sulfonic acid chloride and phenol formaldehyde resin or cresol-formaldehyde resin, naphthoquinone- (1,2) -diazido-4-sulfonic acid chloride and pyrogallol-acetone resin Similarly, the esters are also preferably used.

  The addition amount of the o-quinonediazide compound is preferably in the range of 1 to 50% by weight, more preferably 5 to 30% by weight, and particularly preferably 10 to 30% by weight with respect to the total solid content of the printing plate material. These compounds can be used alone, but may be used as a mixture of several kinds.

  The counter ion of the onium salt includes tetrafluoroboric acid, hexafluorophosphoric acid, triisopropylnaphthalenesulfonic 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-sulfone Examples include acid, 2-methoxy-4-hydroxy-5-benzoyl-benzenesulfonic acid, and paratoluenesulfonic acid. Of these, particularly preferred are alkyl aromatic sulfonic acids such as hexafluorophosphoric acid, triisopropylnaphthalenesulfonic acid and 2,5-dimethylbenzenesulfonic acid.

  The amount of additives other than the o-quinonediazide compound is preferably 1 to 50% by weight, more preferably 5 to 30% by weight, and particularly preferably 10 to 30% by weight.

Further, for the purpose of further improving sensitivity, cyclic acid anhydrides, phenols, and organic acids can be used in combination. Examples of cyclic acid anhydrides include phthalic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, 3,6-endooxy-Δ4-tetrahydrophthalic anhydride, and tetrachlorophthalic anhydride described in US Pat. No. 4,115,128. , Maleic anhydride, chloromaleic anhydride, α-phenylmaleic anhydride, succinic anhydride, pyromellitic anhydride and the like can be used. As phenols, 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. There are sulfonic acids, sulfinic acids, alkylsulfuric acids, phosphonic acids, phosphoric acid esters, carboxylic acids and the like described in Japanese Utility Model Laid-Open No. 60-88942 and Japanese Patent Laid-Open No. 2-96755. p-toluenesulfonic acid, dodecylbenzenesulfonic acid, p-toluenesulfinic acid, ethyl sulfate, phenylphospho Acid, phenylphosphinic acid, phenyl phosphate, diphenyl phosphate, benzoic acid, isophthalic acid, adipic acid, p-toluic acid, 3,4-dimethoxybenzoic acid, phthalic acid, terephthalic acid, 4-cyclohexene-1,2- Examples include dicarboxylic acid, erucic acid, lauric acid, n-undecanoic acid, ascorbic acid and the like.
The proportion of the cyclic acid anhydride, phenols and organic acids in the (A) layer constituting material is preferably 0.05 to 20% by weight, more preferably 0.1 to 15% by weight, particularly preferably 0. .1 to 10% by weight.

In the present invention, in order to improve the stability before development, a fatty acid having a large carbon number called a wax or a derivative thereof can be added to the layer (A). C6-C32 alkyl group or alkenyl group (for example, linear alkyl group such as n-hexyl group, n-heptyl group, n-octyl group, n-nonyl group, n-decyl group, n-undecyl group, 14-methylpentadecyl group, branched alkyl group such as 16-methylheptadecyl group, 1-hexenyl group, 1-heptenyl group, 1-octenyl group, alkenyl group such as 2-methyl-1-heptenyl group) Fatty acids, fatty acid esters, and the like are preferable, and among them, those having an alkyl group or alkenyl group having 25 or less carbon atoms are preferable from the viewpoint of solubility in a coating solvent.
Specific examples of compounds that can be used include enanthic acid, caprylic acid, pelargonic acid, capric acid, undecylic acid, lauric acid, tridecylic acid, myristic acid, pentadecylic acid, palmitic acid, heptadecylic acid, stearic acid, Nonadecanoic acid, arachidic acid, behenic acid, lignoceric acid, serotic acid, heptacosanoic acid, montanic acid, mellicic acid, lacteric acid, undecylenic acid, oleic acid, elaidic acid, cetoleic acid, erucic acid, brassic acid and the like can be mentioned. Examples of fatty acid esters include methyl esters, ethyl esters, propyl esters, butyl esters, dodecyl esters, phenyl esters, and naphthyl esters of these fatty acids. Examples of the thio fatty acid ester include methyl thioester, ethyl thioester, propyl thioester, butyl thioester, and benzyl thioester of these fatty acids. Examples of fatty acid amides include amides, methyl amides, and ethyl amides of these fatty acids.

  Each of these compounds may be used alone or in combination of two or more, and is 0.02 to 10% by weight, preferably 0.2 to 10% by weight, particularly preferably in the total solid content of the printing plate material Used in an addition amount of 2 to 10% by weight. When the amount of the compound is less than 0.02% by weight, the development stability against trauma becomes insufficient, and when the amount is 10% by weight, the effect is saturated, so there is no need to add any more.

In addition, in the (A) layer constituent material, in order to broaden the processing stability against the development conditions, nonionic surface actives as described in JP-A-62-251740 and JP-A-3-208514 are disclosed. An amphoteric surfactant as described in JP-A-59-121044 and JP-A-4-13149 can be added.
Specific examples of the nonionic surfactant include sorbitan tristearate, sorbitan monopalmitate, sorbitan trioleate, stearic acid monoglyceride, polyoxyethylene nonylphenyl ether and the like.
Specific examples of the double-sided activator include alkyldi (aminoethyl) glycine, alkylpolyaminoethylglycine hydrochloride, 2-alkyl-N-carboxyethyl-N-hydroxyethylimidazolinium betaine and N-tetradecyl-N, N-betaine. Type (for example, trade name “Amorgen K” manufactured by Daiichi Kogyo Co., Ltd.). The proportion of the nonionic surfactant and the amphoteric surfactant in the (A) layer constituting material is preferably 0.05 to 15% by weight, more preferably 0.1 to 5% by weight.

In the layer composition material (A) in the present invention, a printing-out agent for obtaining a visible image immediately after heating by exposure, or a dye or pigment as an image colorant can be added.
Typical examples of the printing-out agent include a combination of a compound that releases an acid by heating by exposure (photoacid releasing agent) and an organic dye that can form a salt. Specifically, combinations of o-naphthoquinonediazide-4-sulfonic acid halides and salt-forming organic dyes described in JP-A-50-36209 and JP-A-53-8128, -36223, 54-74728, 60-3626, 61-143748, 61-151644, and 63-58440, and trihalomethyl compounds and salt-forming organic dyes Can be mentioned. Such trihalomethyl compounds include oxazole-based compounds and triazine-based compounds, both of which have excellent temporal stability and give clear printout images.

  As the image colorant, other dyes can be used in addition to the above-mentioned salt-forming organic dyes. Examples of 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 (oriental chemical industry) Manufactured by Co., Ltd.), Victoria Pure Blue, Crystal Violet (CI42555), Methyl Violet (CI42535), Ethyl Violet, Rhodamine B (CI145170B), Malachite Green (CI42000), Methylene Blue (CI522015), and the like. The dyes described in JP-A-62-293247 are particularly preferred. These dyes can be added in a proportion of 0.01 to 10% by weight, preferably 0.1 to 3% by weight, based on the total solid content of the (A) layer constituent material.

Further, a plasticizer can be added to the layer constituting material (A) as needed to impart flexibility of 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 These oligomers and polymers are used.
Furthermore, long chain fatty acid esters, long chain fatty acid amides, and the like may be added to improve film strength.

  In the layer constituting material in the present invention, a surfactant for improving the coating property, for example, a fluorosurfactant described in JP-A-62-170950 can be added. A preferable addition amount is 0.01 to 1% by weight, more preferably 0.05 to 0.5% by weight of the total layer constituting material.

When the image forming material of the present invention is used as a negative type, it is necessary to add a substance that crosslinks with an acid in order to form an alkali-insoluble film (image part).
Examples of the substance that is cross-linked with an acid preferably used in the photosensitive layer of the present invention include (a) two or more hydroxymethyl groups, alkoxymethyl groups, epoxy groups, or vinyl ether groups in the molecule, and these groups are benzene. Examples thereof include a compound bonded to a ring, (b) a compound having an N-hydroxymethyl group, an N-alkoxymethyl group or an N-acyloxymethyl group, and (c) an epoxy compound.
(A) Specific examples of the compound having two or more hydroxymethyl group, alkoxymethyl group, epoxy group or vinyl ether group in the molecule and these groups are bonded to the benzene ring include methylolmelamine, resole Resins, epoxidized novolac resins, urea resins and the like can be mentioned. Furthermore, the compounds described in “Crosslinking agent handbook” (Shinzo Yamashita, Tosuke Kaneko, Taiseisha Co., Ltd.) are also preferred. In particular, a phenol derivative having two or more hydroxymethyl groups or alkoxymethyl groups in the molecule is preferable because the strength of the image area when an image is formed is good. Specifically, a resole resin can be mentioned.

  However, these crosslinking agents that crosslink with an acid are unstable to heat, and the stability during storage after the image recording material is prepared is not so good. In contrast, the molecule contains 3 to 5 benzene rings which have two or more hydroxymethyl groups or alkoxymethyl groups linked to a benzene ring and may have a substituent, and the molecular weight is 1 , 200 or less phenol derivatives have good storage stability and are most preferably used in the present invention. As an alkoxymethyl group which this phenol derivative has, a C6 or less thing is preferable. Specifically, a methoxymethyl group, an ethoxymethyl group, an n-propoxymethyl group, an i-propoxymethyl group, an n-butoxymethyl group, an i-butoxymethyl group, a sec-butoxymethyl group, and a t-butoxymethyl group are preferable. Further, alkoxy-substituted alkoxy groups such as 2-methoxyethoxy group and 2-methoxy-1-propyl group are also preferable.

  A phenol derivative having a hydroxymethyl group can be obtained by reacting a corresponding phenol compound having no hydroxymethyl group with formaldehyde in the presence of a base catalyst. At this time, in order to prevent resinification or gelation, the reaction temperature is preferably 60 ° C. or lower. Specifically, it can be synthesized by the methods described in JP-A-6-282067, JP-A-7-64285 and the like.

A phenol derivative having an alkoxymethyl group can be obtained by reacting a corresponding phenol derivative having a hydroxymethyl group with an alcohol in the presence of an acid catalyst. At this time, in order to prevent resinification and gelation, the reaction temperature is preferably 100 ° C. or lower. Specifically, it can be synthesized by the method described in European Patent EP632003A1 and the like.

(B) As compounds having an N-hydroxymethyl group, an N-alkoxymethyl group or an N-acyloxymethyl group, European Patent Publication (hereinafter referred to as EP-A) No. 0,133,216, West German Patent No. Monomers and oligomers disclosed in US Pat. Nos. 3,634,671 and 3,711,264, melamine-formaldehyde condensates and urea-formaldehyde condensates, disclosed in EP-A 0,212,482 And alkoxy-substituted compounds.
More preferred examples include, for example, melamine-formaldehyde derivatives having at least two free N-hydroxymethyl groups, N-alkoxymethyl groups or N-acyloxymethyl groups, with N-alkoxymethyl derivatives being particularly preferred.

  (C) As an epoxy-type compound, the monomer, dimer, oligomer, polymeric epoxy compound containing one or more epoxy groups can be mentioned. For example, the reaction product of bisphenol A and epichlorohydrin, the reaction product of low molecular weight phenol-formaldehyde resin and epichlorohydrin, etc. are mentioned. Other examples include epoxy resins described and used in US Pat. No. 4,026,705 and British Patent 1,539,192.

In this invention, the addition amount in the case of using the crosslinking agent bridge | crosslinked with an acid is 5-70 weight% in (A) layer solid content, Preferably it is used with the addition amount of 10-65 weight%. If the addition amount of the crosslinking agent that crosslinks with an acid is less than 5% by weight, the film strength of the image area at the time of image recording deteriorates, and if it exceeds 70% by weight, it is not preferable in terms of stability during storage.
These crosslinking agents that crosslink with an acid may be used alone or in combination of two or more.

The coating amount of all materials constituting the applied layer (A) on a support of the image forming material is preferably in the range of ^{0.5~4.0g / m 2, 0.5g / m} 2 If it is less than the range, the effect of improving the printing durability is insufficient, and exceeds 4.0 g / m ² , which is not preferable.

  In the image-forming material of the present invention, 50 (B) a novolak resin which is an aqueous alkali-soluble resin having a phenolic hydroxyl group is further formed on the (A) layer formed of the specific copolymer on the support. A layer containing at least wt% is formed.

  Examples of the resin having a phenolic hydroxyl group which is a main component constituting the layer (B) include phenol formaldehyde resin, m-cresol formaldehyde resin, p-cresol formaldehyde resin, m- / p-mixed cresol formaldehyde resin, phenol / cresol. Mention may be made of novolak resins such as mixed formaldehyde resins (which may be either m-, p- or m- / p-mixed).

These novolak resins having a phenolic hydroxyl group preferably have a weight average molecular weight of 500 to 20,000 and a number average molecular weight of 200 to 10,000.
Furthermore, as described in US Pat. No. 4,123,279, a condensate of phenol and formaldehyde having an alkyl group having 3 to 8 carbon atoms as a substituent, such as t-butylphenol formaldehyde resin and octylphenol formaldehyde resin. May be used in combination. Such resins having a phenolic hydroxyl group may be used alone or in combination of two or more.

The layer (B) contains a compound that generates heat by absorbing light, together with a novolak resin having a phenolic hydroxyl group. The compound that absorbs light and generates heat has a light absorption region in the infrared region of 700 or more, preferably 750 to 1200 nm, and expresses light / heat conversion ability in light in this wavelength range, Specifically, various pigments or dyes that absorb light in this wavelength range and generate heat can be used.
Examples of pigments include commercially available pigment and color index (CI) manuals, “Latest Pigment Handbook” (edited by the Japan Pigment Technology Association, published in 1977), “Latest Pigment Applied Technology” (published by CMC, published in 1986), “Printing” The pigments described in "Ink Technology", published by CMC Publishing, 1984) can be used.

  Examples of the pigment include black pigments, yellow pigments, orange pigments, brown pigments, red pigments, purple pigments, blue pigments, green pigments, fluorescent pigments, metal powder pigments, and other polymer-bonded dyes. Specifically, insoluble azo pigments, azo lake pigments, condensed azo pigments, chelate azo pigments, phthalocyanine pigments, anthraquinone pigments, perylene and perinone pigments, thioindigo pigments, quinacridone pigments, dioxazine pigments, isoindolinone pigments In addition, quinophthalone pigments, dyed 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 surface treatment or may be used after surface treatment. The surface treatment method includes a method of surface coating with a resin or wax, a method of attaching a surfactant, a method of bonding a reactive substance (for example, a silane coupling agent, an epoxy compound, polyisocyanate, etc.) to the pigment surface, etc. Conceivable. The above-mentioned surface treatment methods are described in “Characteristics and Application of Metal Soap” (Shobobo), “Printing Ink Technology” (CMC Publishing, 1984) and “Latest Pigment Application Technology” (CMC Publishing, 1986). Yes.

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. When the particle diameter of the pigment is less than 0.01 μm, it is not preferable from the viewpoint of stability of the dispersion in the photosensitive layer coating solution, and when it exceeds 10 μm, it is not preferable from the viewpoint of uniformity of the photosensitive layer.
As a method for dispersing the pigment, a known dispersion technique used in ink production, toner production, or the like can be used. Examples of the disperser include an ultrasonic disperser, a sand mill, an attritor, a pearl mill, a super mill, a ball mill, an impeller, a disperser, a KD mill, a colloid mill, a dynatron, a three-roll mill, and a pressure kneader. Details are described in "Latest Pigment Applied Technology" (CMC Publishing, 1986).

As the dye, commercially available dyes and known dyes described in the literature (for example, “Dye Handbook” edited by Organic Synthetic Chemical Society, published in 1970) can be used. Specific examples include azo dyes, metal complex azo dyes, pyrazolone azo dyes, anthraquinone dyes, phthalocyanine dyes, carbonium dyes, quinoneimine dyes, methine dyes, and cyanine 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.

  Carbon black is preferably used as a pigment that absorbs such infrared light or near infrared light. Examples of dyes that absorb infrared light or near infrared light include, for example, JP-A-58-125246, JP-A-59-84356, JP-A-59-202829, and JP-A-60-78787. Cyanine dyes described in JP-A-58-173696, JP-A-58-181690, JP-A-58-194595, etc., JP-A-58-112793, Naphthoquinone dyes described in JP-A-58-224793, JP-A-59-48187, JP-A-59-73996, JP-A-60-52940, JP-A-60-63744, etc. And squarylium dyes described in No.-112792, etc., and cyanine dyes described in British Patent No. 434,875.

  Further, near-infrared absorption sensitizers described in US Pat. No. 5,156,938 are also preferably used as dyes, and substituted arylbenzo (thio) pyrylium described in US Pat. No. 3,881,924. Salt, trimethine thiapyrylium salt described in JP-A-57-142645 (US Pat. No. 4,327,169), JP-A-58-181051, 58-220143, 59-41363, 59 -84248, 59-84249, 59-146063, 59-146061, pyrylium compounds described in JP-A-59-216146, cyanine dyes, U.S. Pat. No. 4,283,475 Pentamethine thiopyrylium salt described in No. 5 and pyrylium compounds disclosed in Japanese Patent Publication Nos. 5-13514 and 5-19702, E olight III-178, Epolight III-130, Epolight III-125 and the like are particularly preferably used.

Another particularly preferable example of the dye is a near-infrared absorbing dye described in US Pat. No. 4,756,993 as formulas (I) and (II).
These pigments or dyes are 0.01 to 50% by weight, preferably 0.1 to 10% by weight, particularly preferably 0.5 to 10% by weight, based on the total solid content of the (B) layer constituent material. In the case of a pigment, it can be particularly preferably added in a proportion of 3.1 to 10% by weight. If the added amount of the pigment or dye is less than 0.01% by weight, the sensitivity is lowered, and if it exceeds 50% by weight, the uniformity of the photosensitive layer is lost and the durability of the recording layer is deteriorated.
These dyes or pigments are essential to be added to the layer (B), but may be added to other layers, for example, the layer (A) described above.

  In the present invention, as a compound that absorbs light contained in the layer (B) and generates heat, it is compatible with a resin having a phenolic hydroxyl group, which is a constituent material of the layer (B), to thereby dissolve the resin into alkaline water. A compound that lowers the solubility and decreases the solubility-reducing action by heating may be added. Examples of the compound include those represented by the following general formula (I).

  The compound has the property of absorbing light and generating heat, has an absorption region in the infrared region of 700 nm to 1200 nm, and has good compatibility with an alkaline aqueous solution-soluble resin, and is a basic dye. Since it has a group that interacts with an alkaline water-soluble resin such as an ammonium group or an iminium group in the molecule, it can interact with the resin to control its solubility in alkaline water, and is preferably used in the present invention. Can do.

In the general formula (I), R ^{1 to} R ⁴ are each independently a hydrogen atom or a C 1-12 alkyl group, alkenyl group, alkoxy group, cycloalkyl group, aryl group which may have a substituent. R ¹ and R ² , R ³ and R ⁴ may be bonded to each other to form a ring structure. Specific examples of R ^{1 to} R ⁴ include a hydrogen atom, 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. Further, 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 represents an optionally substituted alkyl group having 1 to 12 carbon atoms, wherein R ^{5 to} R ¹⁰ are specifically a methyl group or an ethyl group. , Phenyl group, dodecyl group, naphthyl group, vinyl group, allyl group, cyclohexyl group and the like. Further, 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, a halogen atom, or an alkyl group having 1 to 8 carbon atoms that may have a substituent, wherein R ¹² is bonded to R ¹¹ or R ^13. A ring structure may be formed, and when m> 2, a plurality of R ¹² may be bonded to each other to form a ring structure. Specific examples of R ^{11 to} R ¹³ include a chlorine atom, a cyclohexyl group, a cyclopentyl ring formed by bonding R ¹² , and a cyclohexyl ring. Further, 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. Moreover, m represents the integer of 1-8, Preferably it is 1-3.
R ^{14 to} R ¹⁵ each independently represent a hydrogen atom, a halogen atom, or an optionally substituted alkyl group having 1 to 8 carbon atoms, and R ¹⁴ is bonded to R ¹⁵ to form a ring structure. Alternatively, when m> 2, a plurality of R ¹⁴ may be bonded to each other to form a ring structure. Specific examples of R ^{14 to} R ¹⁵ include a chlorine atom, a cyclohexyl group, a cyclopentyl ring formed by bonding R ¹⁴ , and a cyclohexyl ring. Further, 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. Moreover, m represents the integer of 1-8, Preferably it is 1-3.

Specific examples of the anion represented by X ⁻ in the general formula (I) include perchloric acid, tetrafluoroboric acid, hexafluorophosphoric acid, triisopropylnaphthalenesulfonic acid, 5-nitro-o-toluenesulfone. Acid, 5-sulfosalicylic acid, 2,5-dimethylbenzenesulfonic acid, 2,4,6-trimethylbenzenesulfonic acid, 2-nitrobenzenesulfonic acid, 3-chlorobenzenesulfonic acid, 3-bromobenzenesulfonic acid, 2-fluorocapryl Mention may be made of naphthalenesulfonic acid, dodecylbenzenesulfonic acid, 1-naphthol-5-sulfonic acid, 2-methoxy-4-hydroxy-5-benzoyl-benzenesulfonic acid, and paratoluenesulfonic acid. Of these, particularly preferred are alkyl aromatic sulfonic acids such as hexafluorophosphoric acid, triisopropylnaphthalenesulfonic acid and 2,5-dimethylbenzenesulfonic acid.

  The compound represented by the general formula (I) is a compound generally referred to as a cyanine dye. Specifically, the following compounds are preferably used, but the present invention is not limited to these specific examples. Absent.

  In the present invention, when a compound such as the above-mentioned cyanine dye is used in the layer (B), the addition amount of this compound is preferably in the range of 99/1 to 70/30 with respect to the aqueous alkaline solution-soluble resin from the viewpoint of sensitivity. The range of 99/1 to 75/25 is more preferable.

  Various additives can be further added to the composition constituting the layer (B) as necessary. Examples of the additive that can be used in the layer (B) include the various additives that can be added to the composition constituting the layer (A). When the present invention is used as a negative type image forming material, it is preferable to add a crosslinking agent to this (B) layer as well as the (A) layer.

  Usually, these photosensitive layers can be produced by dissolving the above-mentioned components in a solvent and coating them on a support. In this case, compatibility due to the influence of a solvent or the like occurs, and there is a possibility that the (A) layer and the (B) layer are not clearly separated, thereby reducing the effect of the present invention. Therefore, in producing the image forming material of the present invention, it is necessary to form the two layers separately.

  As this method, for example, a method using the difference in solvent solubility between the copolymer contained in the layer (A) and the alkali-soluble resin contained in the layer (B), And a method of drying and removing the solvent. Hereinafter, although these methods are explained in full detail, the method of isolate | separating and apply | coating two layers is not limited to these.

The method using the difference in solvent solubility between the copolymer contained in the layer (A) and the aqueous alkali-soluble resin contained in the layer (B) is applied to the layer (A) when applying the aqueous alkaline-soluble resin. A solvent system in which both the specific copolymer contained and the copolymer used in combination with the specific copolymer are insoluble is used. Thereby, even if it carries out 2 layer application | coating, it becomes possible to isolate | separate each layer clearly and to make a coating film.
For example, a copolymer containing a specific monomer constituting a component (A) insoluble in a solvent capable of dissolving an aqueous alkaline solution such as methyl ethyl ketone and 1-methoxy-2-propanol is selected as a copolymer component, (A) Applying and drying the (A) layer mainly comprising the copolymer using a solvent system that dissolves the copolymer constituting the layer component, and then mainly comprising the aqueous alkali-soluble resin (B) layer. Is applied using a solvent that does not dissolve the layer component (A) such as methyl ethyl ketone or 1-methoxy-2-propanol.

On the other hand, the method of drying the solvent very quickly after the second layer is applied is that high-pressure air is blown from a slit nozzle installed almost perpendicular to the running direction of the web, or a heating medium such as steam is supplied inside. This can be achieved by applying thermal energy as conduction heat from the lower surface of the web from a roll (heating roll) or a combination thereof.
FIG. 1 shows an example of the configuration of an apparatus for performing continuous coating and drying used when forming the second layer (B) after the first layer (A) is coated and dried to form a layer. The apparatus of FIG. 1 uses, for example, a roughened aluminum web as a support, and a second layer is formed on the first layer coated product in which the first layer is previously coated on the support. is there.

  The apparatus shown in FIG. 1 has a coating head 2 for coating the first layer coating 1 with a coating solution for the second layer, and a first drying zone 3 for performing high-speed drying by blowing hot air and blowing high-pressure air. And a second drying zone 4 for drying with hot air. The first drying zone 3 includes an air supply port 5 for sending hot air and a high-pressure wind generator 9 for performing high-speed drying. A heat exchanger 10, a pressure gauge 11, a high-pressure air blowing nozzle 12, air volume adjusting dampers 18, 19 and an exhaust port 6 for discharging hot air out of the system are installed. The second drying zone 4 is provided with an air supply port 7 for sending hot air and an exhaust port 8 for discharging outside the hot air system. Further, guide rollers 13 to 17 for conveying the aluminum web 1 are installed at appropriate positions of the apparatus.

In such an apparatus, the first layer ((A) layer) coated article 1 continuously running at 5 to 150 m / min is applied to the second layer ((B) layer) by the application head 2 at 5 to 40 ml / min. The coating is applied at a rate of m ² , and then guided to the first drying zone 3, and the drying proceeds on the first layer coating 1 having a normal temperature of 50 to 150 ° C. The evaporated solvent gas is accompanied by hot air and is discharged out of the system through the exhaust port 6. At the stage of being dried with hot air in the vicinity of the inlet in the first drying zone 3, the second layer coating film is usually in an undried state.

  This undried second-layer coating film is extremely rapidly dried by the high-speed air blown from the high-speed blowing nozzle 12 installed at the transport position at a substantially right angle to the traveling direction of the first-layer coating product 1.

A high-pressure air generated by a high-pressure air generator 9 comprising a compressor or a high-pressure blower is heated to 50 ° C. to 20 ° C. by a heat exchanger 10 and a desired air volume is supplied to the high-speed blowing nozzle 12 by air volume adjusting dampers 18 and 19. After adjusting to supply. As a result, the solvent can be rapidly evaporated in a very short time to form the second layer by vigorously colliding slit-like high-pressure air having a desired temperature and wind speed with the second layer coating film in an undried state. Nozzle 12 the pressure of the normally high-pressure air is 300mmAq (H2 O) ~3kg / cm2 , preferably 1000mmAq~1kg / cm ^2. The wind speed of the blown air from the high-speed wind blowing nozzle 12 is about 20 m / s to 300 m / s. Further, the width between the slits of the high-speed blowing nozzle 12 is about 0.1 mm to 5 mm, but a range of 0.3 mm to 1 mm is desirable. Furthermore, the spray angle of the high-pressure air to the first layer coating 1 is from 0 ° to 90 °, but is preferably from 10 ° to 60 °. The number of nozzles is two in the figure display, but can be about 1 to 8 depending on the drying load.

  In this manner, high-speed drying is performed with the first drying zone 3 to form a coating film for the second layer. Thereafter, the first layer coated product on which the second layer is formed is guided to the second dry zone and heated by hot air of 100 ° C. to 150 ° C. from the air supply port 7. As a result, the amount of residual solvent remaining in a minute amount in the film is controlled in the range of 30 to 200 mg / m @ 2. The dissolved solvent gas is discharged out of the system from the exhaust port 8 together with hot air. A desired two-layer coating can be achieved by these drying operations.

  In forming the photosensitive layer of the image forming material of the present invention, the latter method may be carried out by drying with a heating roll instead of drying with high-speed air as described above. For example, in FIG. 1, the high-pressure air generator 9, the heat exchanger 10, the pressure gauge 11, the high-pressure air blowing nozzle 12 and the air volume adjusting dampers 18 and 19 are not installed, and the guide roll 14 is heated. -The thing of the structure which was made into a thing is mentioned. In such a case, the surface temperature of the roll can be heated to 80 ° C. to 200 ° C. by supplying a heating medium such as steam into the roll. Thermal energy can be given by such a heated roll surface and the aluminum web of the first layer coated product 1, and drying becomes possible.

  Furthermore, this rapid solvent removal method can also be carried out by using drying with a high-speed air and drying with a heating roll in combination. As an apparatus in this case, for example, a device in which the guide roll 14 in FIG. 1 is the same as the heating roll may be used, and the solvent can be evaporated more rapidly.

  In the above example as shown in FIG. 1 and the like, the hot air drying is performed in the first drying zone 3 and then the hot air drying, the drying with the high-pressure air, and the heating roll are performed together. The first hot air drying may be omitted, and the drying with high-pressure air may be performed immediately after the application.

In the production of the image forming material of the present invention, it is preferable to continuously apply and dry using an application / drying apparatus as shown in FIG. 1 from the viewpoint of efficiency and widening the degree of freedom of blending.
In addition, the first layer is coated / dried by providing the same device as that for the second layer upstream of the second layer coating / drying device, and the support is also roughened by applying the first layer. -It is preferable for improving productivity to carry out by providing a roughening means upstream of the coating head of the drying apparatus and continuously carrying the support.

  (A) In the photosensitive image-forming material of the present invention, (A) a layer containing 50% by weight or more of a copolymer containing at least one of (1) to (12) as a copolymerization component; The ratio with the layer containing 50% by weight or more of the novolak resin is arbitrary, but the weight ratio is preferably in the range of 10:90 to 95: 5, particularly preferably in the range of 20:80 to 90:10.

  The photosensitive solution applied to the support is used by dissolving these components in a suitable solvent. The concentration of the above components (total solid content including additives) in the solvent is preferably 1 to 50% by weight. Various methods can be used as the coating method, and examples thereof include bar coater coating, spin coating, spray coating, curtain coating, dip coating, air knife coating, blade coating, and roll coating. As the coating amount decreases, the apparent sensitivity increases, but the film properties of the photosensitive film deteriorate.

The support used in the present invention is a dimensionally stable plate, for example, paper, paper laminated with plastic (for example, polyethylene, polypropylene, polystyrene, etc.), metal plate (for example, aluminum). , Zinc, copper, etc.), plastic films (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 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 that has good dimensional stability and is relatively inexpensive is particularly preferable. A suitable aluminum plate is a pure aluminum plate or an alloy plate containing aluminum as a main component and containing a trace amount of foreign elements, and may be a plastic film on which aluminum is laminated or vapor-deposited. Examples of foreign elements contained in the aluminum alloy include silicon, iron, manganese, copper, magnesium, chromium, zinc, bismuth, nickel, and titanium. The content of foreign elements in the alloy is at most 10% by weight. Particularly suitable aluminum in the present invention is pure aluminum, but completely pure aluminum is difficult to produce in the refining technique, and may contain slightly different elements. Thus, the composition of the aluminum plate applied to the present invention is not specified, and an aluminum plate made of a publicly known 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, and particularly preferably 0.2 mm to 0.3 mm.

Prior to roughening the aluminum plate, a degreasing treatment with, for example, a surfactant, an organic solvent, or an alkaline aqueous solution for removing rolling oil on the surface is performed as desired.
The surface roughening treatment of the aluminum plate is performed by various methods. For example, a method of mechanically roughening, a method of electrochemically dissolving and roughening a surface, and a method of selectively dissolving a surface chemically. This is done by the method of As the mechanical method, a known method such as a ball polishing method, a brush polishing method, a blast polishing method, or a buff polishing method can be used. Further, as an electrochemical surface roughening method, there is a method of performing alternating current or direct current in hydrochloric acid or nitric acid electrolyte. Further, as disclosed in JP-A-54-63902, a method in which both are combined can also be used.
The roughened aluminum plate is subjected to an alkali etching treatment and a neutralization treatment as necessary, and then subjected to an anodization treatment to enhance the water retention and wear resistance of the surface as desired. As the electrolyte used for the anodizing treatment of the aluminum plate, various electrolytes that form a porous oxide film can be used. In general, 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 electrolyte.

The treatment conditions for anodization vary depending on the electrolyte used and cannot be specified in general, but generally the electrolyte concentration is 1 to 80 wt% solution, the liquid temperature is 5 to 70 ° C., 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 anodized film is less than 1.0 g / m ² , the printing durability is insufficient, or the non-image portion of the image forming material is easily damaged, and the ink adheres to the damaged portion during printing. So-called “scratch stains” easily occur.
After the anodizing treatment, the aluminum surface is subjected to a hydrophilic treatment if necessary. The hydrophilization treatment used in the present invention includes an alkali metal silicate (for example, sodium silicate aqueous solution) method as disclosed in US Pat. Nos. 2,714,066, 3,181,461, 3,280,734 and 3,902,734. . In this method, the support is immersed in an aqueous solution of sodium silicate or electrolytically treated. In addition, a method of treating with potassium fluorinated zirconate disclosed in Japanese Patent Publication No. 36-22063 and polyvinylphosphonic acid as disclosed in U.S. Pat.Nos. 3,276,868, 4,153,461, and 4,689,272, etc. Is used.

In the image forming material of the present invention, the (A) layer and the (B) layer are provided as the photosensitive layer on the support, and if necessary, an undercoat layer is provided between the (A) layer and the support. Can be provided.
Various organic compounds are used as the primer layer component. For example, phosphonic acids having an amino group such as carboxymethylcellulose, dextrin, gum arabic, 2-aminoethylphosphonic acid, and phenylphosphonic acid which may have a substituent Organic phosphonic acids such as naphthylphosphonic acid, alkylphosphonic acid, glycerophosphonic acid, methylenediphosphonic acid and ethylenediphosphonic acid, optionally substituted phenylphosphoric acid, naphthylphosphonic acid, alkylphosphoric acid and glycerophosphoric acid Organic phosphoric acid, optionally substituted phenylphosphinic acid, naphthylphosphinic acid, organic phosphinic acids 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.

This organic undercoat layer can be provided by the following method. That is, a method in which water or an organic solvent such as methanol, ethanol, methyl ethyl ketone, or a mixed solvent thereof is dissolved and applied on an aluminum plate and dried, and water, methanol, ethanol, methyl ethyl ketone, etc. In this method, an aluminum plate is immersed in a solution obtained by dissolving the organic compound in an organic solvent or a mixed solvent thereof to adsorb the compound, and then washed with water and dried to provide an organic undercoat layer. . In the former method, a solution having a concentration of 0.005 to 10% by weight of the organic compound can be applied by various methods. In the latter method, the concentration of the solution is 0.01 to 20% by weight, preferably 0.05 to 5% by weight, the immersion temperature is 20 to 90 ° C., preferably 25 to 50 ° C., and the immersion time is It is 0.1 second to 20 minutes, preferably 2 seconds to 1 minute. The solution used for this can be adjusted to a pH range of 1 to 12 with basic substances such as ammonia, triethylamine, potassium hydroxide, and acidic substances such as hydrochloric acid and phosphoric acid. A yellow dye can also be added to improve the tone reproducibility of the image forming material.
The coating amount of the organic undercoat layer is suitably ² to 200 mg / m ² , preferably 5 to 100 mg / m ² . If the coating amount is less than 2 mg / m ² , sufficient printing durability cannot be obtained. Moreover, even if it is larger than 200 mg / m ^2, it is the same.
In the image forming material of the present invention, a protective layer may be provided on the photosensitive layer as necessary. Examples of the protective layer component include polyvinyl alcohol and mat materials used for ordinary photosensitive image forming materials.

The image forming material prepared as described above is usually subjected to image exposure and development processing.
In the present invention, the active light source used for image exposure is preferably a light source having an emission wavelength of 700 nm or more in the near infrared to infrared region, and a solid laser or a semiconductor laser is particularly preferable.

Conventionally known alkaline aqueous solutions can be used as the developer and replenisher for the image forming material of the present invention. For example, sodium silicate, potassium, tribasic sodium phosphate, potassium, ammonium, dibasic sodium phosphate, potassium, ammonium, sodium carbonate, potassium, ammonium, sodium bicarbonate, potassium, Examples thereof include inorganic alkali salts such as ammonium, sodium borate, potassium, ammonium, sodium hydroxide, ammonium, potassium and lithium. Moreover, 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 that the developability can be adjusted by the ratio and concentration of silicon oxide SiO ₂ and alkali metal oxide M ₂ O which are silicate components. For example, Japanese Patent Application Laid-Open No. Sho 54-62004, Alkali metal silicates as described in JP-B-57-7427 are effectively used.

Further, when developing using an automatic developing machine, an aqueous solution (replenisher) having a higher alkali strength than that of the developer is added to the developer, so that a large amount of developer can be obtained without replacing the developer in the developer tank for a long time. It is known that PS plates can be processed. This replenishment method is also preferably applied in the present invention. Various surfactants and organic solvents can be added to the developer and the replenisher as necessary for the purpose of promoting or suppressing developability, dispersing development residue, and improving the ink affinity of the printing plate image area. Preferred surfactants include anionic, cationic, nonionic and amphoteric surfactants.
If necessary, the developer and replenisher may contain reducing agents such as hydroquinone, resorcin, sulfurous acid, bisulfite, and other inorganic acids such as sodium salts and potassium salts, and organic carboxylic acids, antifoaming agents, and hard water softeners. It can also be added.
The printing plate developed using the developer and the replenisher is post-treated with a desensitizing solution containing washing water, a rinsing solution containing a surfactant or the like, gum arabic or a starch derivative. As the post-treatment when the image forming material of the present invention is used as a printing plate, these treatments can be used in various combinations.

In recent years, automatic developing machines for printing plates have been widely used in the plate making and printing industries in order to rationalize and standardize plate making operations. This automatic developing machine is generally composed of a developing unit and a post-processing unit, and includes an apparatus for conveying the printing plate, each processing liquid tank, and a spray device, and each pumped up by a pump while conveying the exposed printing plate horizontally. The processing liquid is sprayed from the spray nozzle and developed. In addition, recently, a method is also known in which a printing plate is dipped and conveyed by a submerged guide roll or the like in a processing liquid tank filled with the processing liquid. In such automatic processing, each processing solution can be processed while being supplemented with a replenisher according to the processing amount, operating time, and the like.
In addition, a so-called disposable processing method in which processing is performed with a substantially unused processing solution can also be applied.

  The case where the image forming material of the present invention is used as a photosensitive lithographic printing plate will be described. If there is an unnecessary image part (for example, film edge mark of the original film) on the planographic printing plate obtained by image exposure, development, washing and / or rinsing and / or gumming, it is unnecessary. The image portion is erased. Such erasing is preferably performed by applying an erasing solution as described in, for example, Japanese Patent Publication No. 2-13293 to an unnecessary image portion, leaving it for a predetermined time, and then washing with water. A method of developing after irradiating an unnecessary image portion with an actinic ray guided by an optical fiber as described in JP-A-59-174842 can also be used.

The lithographic printing plate obtained as described above can be subjected to a printing process after applying a desensitized gum if desired. However, if it is desired to obtain a lithographic printing plate with a higher printing durability, a burning treatment is performed. Is given.
In the case of burning a lithographic printing plate, prior to burning, adjustments such as those described in Japanese Patent Publication Nos. 61-2518, 55-28062, JP-A 62-31859, and 61-159655 are required. It is preferable to treat with a surface liquid.
As its method, with a sponge or absorbent cotton soaked with the surface-adjusting liquid, it is applied onto a lithographic printing plate, or a method in which the printing plate is immersed and applied in a vat filled with the surface-adjusting liquid, Application by an automatic coater is applied. Further, it is more preferable to make the coating amount uniform with a squeegee or a squeegee roller after coating.

In general, the amount of surface-adjusting solution applied is suitably 0.03 to 0.8 g / m ² (dry weight).
The lithographic printing plate coated with the surface-adjusting solution is dried if necessary, and then heated to a high temperature with a burning processor (for example, burning processor “BP-1300” sold by Fuji Photo Film Co., Ltd.). The In this case, the heating temperature and time are in the range of 180 to 300 ° C. and preferably in the range of 1 to 20 minutes, although depending on the type of components forming the image.

The lithographic printing plate that has been burned can be subjected to conventional treatments such as washing and gumming as needed, but a surface-conditioning solution containing a water-soluble polymer compound is used. In such a case, a so-called desensitizing treatment such as gumming can be omitted.
The planographic printing plate obtained by such processing is applied to an offset printing machine or the like and used for printing a large number of sheets.

  EXAMPLES Hereinafter, although this invention is demonstrated according to an Example, the scope of the present invention is not limited to these Examples.

[Synthesis of (A) Component Copolymer]
Synthesis Example 1 (Copolymer 1)
A 500 ml three-necked flask equipped with a stirrer, a condenser tube and a dropping funnel is charged with 31.0 g (0.36 mol) of methacrylic acid, 39.1 g (0.36 mol) of ethyl chloroformate and 200 ml of acetonitrile while cooling in an ice-water bath. The mixture was stirred. To this mixture, 36.4 g (0.36 mol) of triethylamine was dropped with a dropping funnel over about 1 hour. After completion of the dropwise addition, the ice-water bath was removed, and the mixture was stirred at room temperature for 30 minutes.

  To this reaction mixture, 51.7 g (0.30 mol) of p-aminobenzenesulfonamide was added, and the mixture was stirred for 1 hour while warming to 70 ° C. in an oil bath. After completion of the reaction, the mixture was added to 1 liter of water with stirring, and the resulting mixture was stirred for 30 minutes. The mixture was filtered to take out a precipitate, which was slurried with 500 ml of water, then the slurry was filtered, and the obtained solid was dried to dry a white solid of N- (p-aminosulfonylphenyl) methacrylamide. Was obtained (yield 46.9 g).

  Next, in a 100 ml three-necked flask equipped with a stirrer, a condenser tube and a dropping funnel, 5.04 g (0.0210 mol) of N- (p-aminosulfonylphenyl) methacrylamide and 2.05 g (0.0180 mol) of ethyl methacrylate. Then, 1.11 g (0.021 mol) of acrylonitrile and 20 g of N, N-dimethylacetamide were added, and the mixture was stirred while being heated to 65 ° C. with a hot water bath. To this mixture, 0.15 g of “V-65” (manufactured by Wako Pure Chemical Industries, Ltd.) was added, and the mixture was stirred for 2 hours under a nitrogen stream while maintaining at 65 ° C. This reaction mixture was further mixed with 5.04 g of N- (p-aminosulfonylphenyl) methacrylamide, 2.05 g of ethyl methacrylate, 1.11 g of acrylonitrile, 20 g of N, N-dimethylacetamide and 0.15 g of “V-65”. Was dropped by a dropping funnel over 2 hours. After completion of the dropwise addition, the resulting mixture was further stirred at 65 ° C. for 2 hours. After completion of the reaction, 40 g of methanol was added to the mixture, cooled, and the resulting mixture was poured into 2 liters of water while stirring the water. After stirring the mixture for 30 minutes, the precipitate was removed by filtration and dried. 15 g of a white solid was obtained. It was 53,000 when the weight average molecular weight (polystyrene standard) of this copolymer 1 was measured by the gel permeation chromatography.

Synthesis Example 2 (Copolymer 2)
In the polymerization reaction of Synthesis Example 1, N- (p-aminosulfonylphenyl) methacrylamide 5.04 g (0.0210 mol) was changed to N- (p-hydroxyphenyl) methacrylamide 3.72 g (0.0210 mol). Except for the above, a polymerization reaction was carried out in the same manner as in Synthesis Example 1 to obtain a copolymer 2 having a weight average molecular weight (polystyrene standard) of 47,000.

[Production of substrate]
An aluminum plate (material 1050) having a thickness of 0.3 mm was washed with trichlorethylene and degreased, and then the surface was grained using a nylon brush and a 400 mesh pumice-water suspension and thoroughly washed with water. This plate was etched by being immersed in a 25% aqueous sodium hydroxide solution 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. Next, this plate was provided with a direct current anodic oxide film having a current density of 15 A / dm @ 2 and 3 g / m @ 2 using 7% sulfuric acid as an electrolyte, then washed with water, dried, and further coated with the following undercoat liquid. Dry at 1 ° C. for 1 minute. The coating amount after drying was 10 mg / m @ 2.

Undercoat liquid β-alanine 0.5g
Methanol 95g
5g of water

Example 1
The following photosensitive solution A1 was applied to the obtained substrate and dried at 100 ° C. for 2 minutes to form a layer (A). The coating amount after drying was 1.4 g / m ² .
Thereafter, the following photosensitive solution B1 was applied and dried at 100 ° C. for 2 minutes to form a layer (B) to obtain a lithographic printing plate. The total coating amount of the photosensitive solution after drying was 2.0 g / m ² .

Photosensitizer A1
0.75 g of copolymer 1
Cyanine dye A 0.04g
0.002 g of p-toluenesulfonic acid
Tetrahydrophthalic anhydride 0.05g
Victoria Pure Blue (Dye with BOH counter anion as 1-naphthalene sulfonate anion) 0.015 g
Fluorosurfactant (Megafac F-177,
Dainippon Ink & Chemicals, Inc.) 0.02g
γ-butyrolactone 8g
7g of methyl ethyl ketone
1-methoxy-2-propanol 7g

Photosensitive solution B1
m, p-cresol novolak (m / p ratio = 6/4,
Weight average molecular weight 4000) 0.25 g
Cyanine dye A 0.05g
N-dodecyl stearate 0.02 g
Fluorosurfactant (Megafac F-177,
Dainippon Ink & Chemicals, Inc.) 0.05g
7g of methyl ethyl ketone
1-methoxy-2-propanol 7g

Example 2
The following photosensitive solution A2 was applied to the obtained substrate and dried at 100 ° C. for 2 minutes to form a layer (A). The coating amount after drying was 1.5 g / m ² .
Thereafter, the following photosensitive solution B2 was applied and dried by the following method. That is, using the dry zone shown in FIG. 1, immediately after application, high-pressure air of 3000 mmAq is blown from the slit nozzle 12, and the guide roll 14 is changed to a heating roll, and heating at 130 ° C. is performed. The layer (B) was formed, and a lithographic printing plate was obtained. The total coating amount of the photosensitive solution after drying was 2.0 g / m ² .
Photosensitive solution A2
m, p-cresol novolak (m / p ratio = 6/4,
(Weight average molecular weight 4000) 0.75 g
Copolymer 2 0.10g
Cyanine dye B 0.3g
2,6-bishydroxymethyl-p-cresol 0.02 g
p-Toluenesulfonic acid 0.005g
Tetrahydrophthalic anhydride 0.01g
Victoria Pure Blue (Dye with BOH counter anion as 1-naphthalene sulfonate anion) 0.015 g
Fluorosurfactant (Megafac F-177,
Dainippon Ink & Chemicals, Inc.) 0.02g
Methyl ethyl ketone 12g
1-methoxy-2-propanol 10g

Photosensitive solution B2
m, p-cresol novolak (m / p ratio = 6/4,
Weight average molecular weight 4000) 0.25 g
Cyanine dye B 0.07g
N-dodecyl stearate 0.02 g
Fluorosurfactant (Megafac F-177,
Dainippon Ink & Chemicals, Inc.) 0.05g
7g of methyl ethyl ketone
1-methoxy-2-propanol 7g

Comparative Example 1
Only the photosensitive solution A1 used in Example 1 was applied to the obtained substrate and dried at 100 ° C. for 2 minutes to form a photosensitive layer, whereby a lithographic printing plate was obtained. The coating amount after drying was 1.4 g / m ² .

Comparative Example 2
Except that the copolymer 1 was replaced with m, p-cresol novolak (m / p ratio = 6/4, weight average molecular weight 4000) in the photosensitive solution A1 used in Example 1 on the obtained substrate. The same thing was apply | coated and it dried at 100 degreeC for 2 minute (s), the photosensitive layer was formed, and the lithographic printing plate was obtained. The coating amount after drying was 1.4 g / m ² .

[Performance evaluation of planographic printing plates]
For the planographic printing plates of Examples 1 and 2 and Comparative Examples 1 and 2 prepared as described above, performance evaluation was performed according to the following criteria. The evaluation results are shown in Table 1.

(Sensitivity and development latitude)
The resulting lithographic printing plate was exposed at a main scanning speed of 5 m / sec using a semiconductor laser having an output of 500 mW, a wavelength of 830 nm, and a beam diameter of 17 μm (1 / e ² ), and then a developer manufactured by Fuji Photo Film Co., Ltd. , DP-4, and rinse solution FR-3 (1: 7) were developed using an automatic processor (Fuji Photo Film Co., Ltd .: “PS processor 900VR”). At that time, DP-4 was used in two levels: 1: 8 diluted and 1: 6 diluted, and the line width of the non-image area obtained with each developer was measured. The irradiation energy of the laser corresponding to is obtained, and this was taken as the sensitivity. The difference between the standard 1: 8 dilution and the 1: 6 dilution was recorded. The smaller the difference, the better the development latitude. If it is 20 mJ / cm ² or less, it is a practical level.
(Print life)
Using a planographic printing plate developed using DP-4 (1: 8), printing was performed on high-quality paper using a Heidel KOR-D machine manufactured by Heidelberg. Printing was performed while wiping the plate surface with a cleaner liquid (Fuji Photo Film Co., Ltd .: “Plate Cleaner CL2”) every 5000 sheets printed. Table 1 shows the final number of printed sheets. Here, the final number of printed sheets is the number of sheets until the so-called plate skipping occurs, in which the photosensitive layer of the planographic printing plate is reduced in film thickness and partially loses ink.

  From Table 1, the lithographic printing plate according to the present invention has a two-layered photosensitive layer (A) layer and (B) layer. In contrast to Comparative Examples 1 and 2, the development latitude and resistance It can be seen that the printability is excellent and the sensitivity is also good. On the other hand, the comparative example in which only the layer (A) is a photosensitive layer is inferior in development latitude, and in particular, Comparative Example 2 in which the copolymer having the specific monomer of the present invention is not used has extremely low printing durability. .

It is a schematic block diagram which shows the one aspect | mode of the continuous application drying apparatus used for manufacture of the image forming material of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 1st layer coating material 2 Application | coating head 3 1st drying zone 4 2nd drying zone 5 Air inlet (1st drying zone)
6 Exhaust port (first drying zone)
7 Air intake (second drying zone)
8 Exhaust port (second drying zone)
9 High Pressure Air Generator 10 Heat Exchanger 11 Pressure Gauge 12 High Pressure Air Blowout Nozzle 13, 14, 15, 16, 17 Guide Roll 18, 19 Air Volume Control Damper

Claims (1)

A layer containing 50% by weight or more of a copolymer containing (A) at least one selected from the group consisting of the following monomers (1) to (12) as a copolymerization component on the support; and (B) a novolak A photosensitive image forming material for an infrared laser, wherein a layer containing 50% by weight or more of a resin is sequentially laminated.
(1) Acrylic acid ester and methacrylic acid ester having an aliphatic hydroxyl group,
(2) alkyl acrylate,
(3) alkyl methacrylate,
(4) Acrylamide and methacrylamide,
(5) vinyl ethers,
(6) vinyl esters,
(7) Styrenes,
(8) vinyl ketones,
(9) olefins,
(10) N-vinylpyrrolidone, N-vinylcarbazole, 4-vinylpyridine, acrylonitrile and methacrylonitrile,
(11) unsaturated imide,
(12) Unsaturated carboxylic acid.

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