JP2005091479A - Photosensitive composition - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a photosensitive composition providing a lithographic printing plate which has superior wear resistance and chemical resistance, has large printing resistance to normal ink or UV ink, and form no stain in printing. <P>SOLUTION: The photosensitive composition which includes a specified structural unit, is water-insoluble and alkali-soluble, and contain o-naphthoquinone azide provides a lithographic printing paper characterized in that: a base is coated well; wear resistance and chemical resistance are superior; excellent printed matter can be obtained in quantities even when printing using UV ink is carried out without performing burning processing; printing resistance is superior; and no stain is formed during printing. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a photosensitive composition suitable for the production of lithographic printing plates, IC circuits and photomasks. More specifically, the present invention relates to a photosensitive composition comprising a photosensitive compound acting positively and a polymer compound excellent in wear resistance and chemical resistance.

A photosensitive composition comprising an o-naphthoquinone diazide compound and a novolac type phenolic resin has been used industrially as a very excellent photosensitive composition for the production of a lithographic printing plate and as a photoresist.
However, the novolac type phenolic resin used as the main component has poor adhesion to the substrate due to its properties, the film is brittle, the coating property is inferior, the abrasion resistance is inferior, and the printing durability when used in a lithographic printing plate is low. There are points to be improved, such as insufficient ink resistance and poor chemical resistance, especially when UV ink is used.
As a method for improving these various performances, burning treatment (heating treatment after exposure and development) is generally used. However, when the burning process is performed, there is a problem that the low molecular weight compound sublimates from the photosensitive layer in the image area and adheres to the non-image area, and stains easily occur during printing.

  In order to solve such problems, various polymer compounds have been studied as binders. For example, polyhydroxystyrene or hydroxystyrene copolymer has certainly improved coating properties, but has the disadvantage of poor wear resistance and chemical resistance (see, for example, Patent Document 1). It has also been proposed to use a polymer compound having a structural unit of an acrylic acid derivative in the molecular structure as a binder, but such a polymer compound has a narrow range of appropriate development conditions and is not sufficiently wear resistant. There were problems such as. In addition, it has been proposed to use a polymer compound having a sulfonamide group as a binder (for example, see Patent Document 2), or to use a resin having a urea bond in the side chain as a binder (for example, see Patent Document 3). ). However, there is still a problem that the abrasion resistance is not sufficient and the stains are likely to occur during printing.

Japanese Patent Publication No.52-41050 JP-A-2-866 JP-A-8-339082

Accordingly, an object of the present invention is to provide a photosensitive composition which can be developed with an aqueous alkaline developer, gives a lithographic printing plate having excellent abrasion resistance and high printing durability.
Another object of the present invention is to provide a photosensitive composition that is excellent in chemical resistance and gives a lithographic printing plate having high printing durability even when printing using UV ink is performed without performing a burning treatment. .
It is a further object of the present invention to provide a photosensitive composition that provides a lithographic printing plate that has a wide range of development conditions and does not cause smearing during printing.
A further object of the present invention is to provide a photosensitive composition having good adhesion to a substrate, providing a flexible film, and excellent organic solvent solubility.

  As a result of intensive studies, the present inventors have obtained a photosensitive composition characterized by comprising a water-insoluble and alkali-soluble polyamide resin having a specific structural unit, and o-naphthoquinonediazide. Has been achieved, and the present invention has been completed. That is, the present invention relates to a photosensitive composition comprising a polyamide resin containing a structural unit represented by the following general formula (I), water-insoluble and alkali-soluble, and o-naphthoquinonediazide. Is.

式（Ｉ）中、Ｒ¹は置換基を有していてもよい、少なくとも１つ以上の芳香族環を有する連結基を表し、２つの−ＣＯＯＨは芳香族環に直接結合する。Ｒ²は置換基を有していてもよい、アルキレン基、アリーレン基、またはアラルキレン基を表す。

In formula (I), R ¹ represents an optionally substituted linking group having at least one aromatic ring, and the two —COOH are directly bonded to the aromatic ring. R ² represents an alkylene group, an arylene group or an aralkylene group which may have a substituent.

As described above, when the photosensitive composition of the present invention is used for a lithographic printing plate, it contains the above-mentioned structural unit and contains a water-insoluble and alkali-soluble polyamide resin, thereby allowing the photosensitive layer to adhere to the substrate. It gives a flexible film and is excellent in solubility in organic solvents, so it has excellent coatability when coated on a support, and when the exposed area is used with an aqueous alkaline developer after coating, drying and image exposure. Excellent developability. Further, the obtained relief image has good wear resistance and adhesion to the support, and when used as a printing plate, a large number of good prints can be obtained.
In addition, a lithographic printing plate that has excellent chemical resistance and can produce a large number of good prints even when printing is performed using UV ink without burning treatment. There is an effect of providing.

The photosensitive composition of the present invention is characterized by containing a water-insoluble and alkali-soluble polyamide resin having a specific structure and o-naphthoquinonediazide.
Hereinafter, each structure of the photosensitive composition of this invention is demonstrated in detail sequentially.
The photosensitive composition of the present invention comprises a polyamide resin containing a structural unit represented by the general formula (I) and water-insoluble and alkali-soluble (hereinafter referred to as “specific polyamide resin” as appropriate). And
The specific polyamide resin used in the present invention is not particularly limited as long as it contains a structural unit represented by the following general formula (I), is insoluble in water, and is soluble in an alkaline aqueous solution.

In formula (I), R ¹ represents an optionally substituted linking group having at least one aromatic ring, and each of the two —COOH is directly bonded to the aromatic ring. In addition, when R ¹ has two or more aromatic rings, these aromatic rings are bonded via a single bond or a linking group, or have a condensed polycyclic structure It may be. Furthermore, —COOH is bonded to an aromatic ring directly bonded to the amide group, and in that case, it is generally bonded to the ortho position with respect to the amide group.
Examples of the substituent of the aromatic ring include, for example, an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, a halogen atom (—F, —Cl, —Br, —I), —CONH. ₂ , -OH, -SH and the like.
Specific examples of such a linking group represented by R ¹ and —COOH include the following, but the present invention is not limited thereto.

In the formula (I), R ² represents an alkylene group, an arylene group or an aralkylene group which may have a substituent.
These alkylene group, arylene group and aralkylene group are not particularly limited, but the alkylene group preferably has about 2 to 10 carbon atoms, and the arylene group has a single bond having two or more ring structures. Alternatively, it may be bonded via a linking group. Examples of the aralkylene group include those in which the alkylene group and the arylene group are appropriately combined.
Examples of the substituent on the alkylene group, arylene group, and aralkylene group include, for example, an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, and a halogen atom (-F, -Cl, -Br, -I). , -CONH _2, -OH, -SH, and the like.
Specific examples of such a linking group represented by R ² include the following, but the present invention is not limited thereto.

Such a specific polyamide resin can be usually produced by polymerizing an aromatic tetracarboxylic dianhydride and a diamine by a conventionally known method.
Aromatic tetracarboxylic dianhydrides used for the synthesis of specific polyamide resins include pyromellitic acid, 3,3 ', 4,4'-benzophenone tetracarboxylic acid, 2,3,3', 4'-biphenyltetra. And dianhydrides of carboxylic acid, 2,3,6,7-naphthalenetetracarboxylic acid, 4,4′-sulfonyltetracarboxylic acid, and 3,3 ′, 4,4′-diphenylethertetracarboxylic acid. it can.

  Examples of the diamine include p-xylylenediamine, m-phenylenediamine, p-phenylenediamine, 4,4'-diaminodiphenylpropane, 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenyl ether, 4,4. '-Diaminodiphenylsulfone, 3,3'-dimethyl-4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenyl, 1,5-diaminonaphthalene, 1,4-diaminoanthraquinone, 2,6-diaminoanthraquinone, Examples include 2,6-diaminoanisole, 2,6-diaminopyridine, 4,6-diamino-2-mercaptopyrimidine, 1,6-diaminohexane, and the like.

The polymerization ratio of the aromatic tetracarboxylic dianhydride and the diamine is preferably 60:40 to 40:60, and more preferably 55:45 to 45:55.
In addition, as these particularly preferable combinations, 3,3 ′, 4,4′-benzophenone tetracarboxylic acid is used as the aromatic tetracarboxylic dianhydride, and 4,4′-diaminodiphenyl ether is used as the diamine as the chemical resistance. From the viewpoint of, it is preferably used.
In addition, the specific polyamide resin according to the present invention may be formed using two or more of the tetracarboxylic dianhydrides and diamines. Moreover, in order to improve coating solvent solubility, you may use together with aliphatic diamine.

  The weight average molecular weight (Mw) of the specific polyamide resin according to the present invention is preferably in the range of 3,000 to 100,000, and more preferably in the range of 5,000 to 50,000. These specific polyamide resins may be used alone or in combination of two or more.

The resin according to the present invention may contain an unreacted monomer. In this case, the proportion of the monomer in the polymer compound is desirably 15% by mass or less.
The resins of the present invention may be used alone or in combination. The content of these polymer compounds contained in the photosensitive composition is about 5 to 95% by mass, preferably about 10 to 85% by mass.

  The o-naphthoquinonediazide compound used in the present invention is preferably an ester of 1,2-diazonaphthoquinonesulfonic acid chloride and pyrogallol-acetone resin described in JP-B-43-28403. Other suitable orthoquinonediazide compounds include 1,2-diazonaphthoquinonesulfonic acid chloride and phenol-formaldehyde resin described in US Pat. Nos. 3,046,120 and 3,188,210. There is an ester with. Other useful o-naphthoquinone diazide compounds are reported and known in numerous patents. For example, JP-A-47-5303, JP-A-48-63802, JP-A-48-63803, JP-A-48-96575, JP-A-49-38701, JP-A-48-13354, JP-B-37-18015. No. 41-11222, No. 45-9610, No. 49-17481, US Pat. No. 2,797,213, No. 3,454,400, No. 3,544,323. No. 3,573,917, No. 3,674,495, No. 3,785,825, British Patent No. 1,227,602, No. 1,251,345, No. No. 1,267,005, No. 1,329,888, No. 1,330,932, German Patent No. 854,890, etc. Can do.

  A particularly preferred o-naphthoquinonediazide compound in the present invention is a compound obtained by a reaction between a polyhydroxy compound having a molecular weight of 1,000 or less and 1,2-diazonaphthoquinonesulfonic acid chloride. Specific examples of such compounds include JP-A Nos. 51-139402, 58-150948, 58-203434, 59-165053, 60-112445, 60-134235, and 60-. No. 163043, No. 61-118744, No. 62-10645, No. 62-10646, No. 62-153950, No. 62-178562, Japanese Patent Application No. 62-233292, US Pat. No. 3,102,809 No. 3,126,281, No. 3,130,047, No. 3,148,983, No. 3,184,310, No. 3,188,210, No. 4, The thing described in each gazette or specification, such as 639,406, can be mentioned.

  When synthesizing these o-naphthoquinonediazide compounds, it is preferable to react 0.2 to 1.2 equivalents of 1,2-diazonaphthoquinonesulfonic acid chloride with respect to the hydroxyl group of the polyhydroxy compound, and further 0.3. It is preferable to carry out ~ 1.0 equivalent reaction.

The obtained o-naphthoquinone diazide compound is a mixture of different positions and introduction amounts of 1,2-diazonaphthoquinonesulfonic acid ester groups, but all hydroxyl groups are converted with 1,2-diazonaphthoquinonesulfonic acid esters. The proportion of the resulting compound in the mixture (the content of the completely esterified compound) is preferably 5 mol% or more, more preferably 20 to 99 mol%.
The amount of the o-naphthoquinonediazide compound in the photosensitive composition of the present invention is 5 to 95% by mass, preferably 10 to 50% by mass, and more preferably 15 to 40% by mass.

In addition to the water-insoluble and alkali-soluble polyamide resin according to the present invention, other water-insoluble and alkali-soluble resins can be used in the composition of the present invention. Such a resin is not particularly limited as long as it has a property of being dissolved when contacted with an alkaline developer, but a homopolymer containing an acidic group in the main chain and / or side chain of the resin, and a copolymer thereof. A polymer or a mixture thereof is preferable.
As such an alkali-soluble resin having an acidic group, in particular, a polymer compound having a functional group in any one of (1) a phenolic hydroxyl group, (2) a sulfonamide group, and (3) an active imide group. Can be mentioned. For example, although the following are illustrated, this invention is not limited to these.

  (1) Examples of the resin (polymer compound) having a phenolic hydroxyl group include phenol formaldehyde resin, m-cresol formaldehyde resin, p-cresol formaldehyde resin, m- / p-mixed cresol formaldehyde resin, phenol / cresol (m Any of-, p-, and m- / p-mixing may be used. Examples thereof include novolak resins such as mixed formaldehyde resins and pyrogallol acetone resins. In addition to this, a polymer compound having a phenolic hydroxyl group in the side chain is preferably used as the polymer compound having a phenolic hydroxyl group. As a polymer compound having a phenolic hydroxyl group in the side chain, a polymerizable monomer comprising a low molecular compound having at least one phenolic hydroxyl group and at least one polymerizable unsaturated bond is homopolymerized, or other polymerization is performed on the monomer. And a high molecular compound obtained by copolymerizing a functional monomer.

  Examples of the polymerizable monomer having a phenolic hydroxyl group include acrylamide, methacrylamide, acrylic acid ester, methacrylic acid ester, and hydroxystyrene having a phenolic hydroxyl group. Specifically, N- (2-hydroxyphenyl) acrylamide, N- (3-hydroxyphenyl) acrylamide, N- (4-hydroxyphenyl) acrylamide, N- (2-hydroxyphenyl) methacrylamide, N -(3-Hydroxyphenyl) methacrylamide, N- (4-Hydroxyphenyl) methacrylamide, o-Hydroxyphenyl acrylate, m-Hydroxyphenyl acrylate, p-Hydroxyphenyl acrylate, o-Hydroxyphenyl methacrylate , M-hydroxyphenyl methacrylate, p-hydroxyphenyl methacrylate, o-hydroxystyrene, m-hydroxystyrene, p-hydroxystyrene, 2- (2-hydroxyphenyl) ethyl acrylate, 2- (3-hydroxyphenyl) ethyl Acrylate, 2- 4-hydroxyphenyl) ethyl acrylate, 2- (2-hydroxyphenyl) ethyl methacrylate, 2- (3-hydroxyphenyl) ethyl methacrylate can be suitably used 2- (4-hydroxyphenyl) ethyl methacrylate. Such resins having a phenolic hydroxyl group may be used in combination of two or more. Furthermore, as described in US Pat. No. 4,123,279, 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, These copolymers may be used in combination.

(2) Examples of the alkali-soluble resin having a sulfonamide group include polymer compounds obtained by homopolymerizing a polymerizable monomer having a sulfonamide group or copolymerizing the monomer with another polymerizable monomer. The polymerizable monomer having a sulfonamide group includes one or more sulfonamide groups —NH—SO ₂ — in which at least one hydrogen atom is bonded on a nitrogen atom and one or more polymerizable unsaturated bonds in one molecule. And a polymerizable monomer comprising a low molecular weight compound. Among them, 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.

(3) The alkali-soluble resin having an active imide group is preferably one having an active imide group in the molecule, and the polymer compound has one unsaturated bond polymerizable with the active imide group in each molecule. Examples thereof include a polymer compound obtained by homopolymerizing a polymerizable monomer comprising the above-described low molecular weight compound, or copolymerizing the monomer with another polymerizable monomer.
As such a compound, specifically, N- (p-toluenesulfonyl) methacrylamide, N- (p-toluenesulfonyl) acrylamide and the like can be preferably used.

Furthermore, as the alkali-soluble resin that can be used in the present invention, one or two kinds selected from the polymerizable monomer having a phenolic hydroxyl group, the polymerizable monomer having a sulfonamide group, or the polymerizable monomer having an active imide group are used. In addition to the above polymerizable monomers, a polymer compound obtained by copolymerizing another polymerizable monomer is preferable. As a copolymerization ratio in this case, it is preferable that the monomer which provides alkali solubility is contained 10 mol% or more, and what contains 20 mol% or more is more preferable. If the copolymerization component of the monomer imparting alkali solubility is less than 10 mol%, alkali solubility tends to be insufficient, and developability tends to be lowered.
Examples of other polymerizable monomers that can be used here include the compounds listed in the following (m1) to (m12), but the present invention is not limited thereto.

(M1) Acrylic acid esters and methacrylic acid esters having an aliphatic hydroxyl group such as 2-hydroxyethyl acrylate or 2-hydroxyethyl methacrylate.
(M2) Alkyl acrylates such as methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, amyl acrylate, hexyl acrylate, octyl acrylate, benzyl acrylate, 2-chloroethyl acrylate, and glycidyl acrylate.
(M3) Alkyl methacrylates such as methyl methacrylate, ethyl methacrylate, propyl methacrylate, butyl methacrylate, amyl methacrylate, hexyl methacrylate, cyclohexyl methacrylate, benzyl methacrylate, 2-chloroethyl methacrylate and glycidyl methacrylate.
(M4) 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.

(M5) 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.
(M6) Vinyl esters such as vinyl acetate, vinyl chloroacetate, vinyl butyrate and vinyl benzoate.
(M7) Styrenes such as styrene, α-methylstyrene, methylstyrene, chloromethylstyrene.
(M8) Vinyl ketones such as methyl vinyl ketone, ethyl vinyl ketone, propyl vinyl ketone, and phenyl vinyl ketone.
(M9) Olefins such as ethylene, propylene, isobutylene, butadiene and isoprene.
(M10) N-vinylpyrrolidone, acrylonitrile, methacrylonitrile and the like.
(M11) Unsaturated imides such as maleimide, N-acryloylacrylamide, N-acetylmethacrylamide, N-propionylmethacrylamide, N- (p-chlorobenzoyl) methacrylamide.
(M12) Unsaturated carboxylic acids such as acrylic acid, methacrylic acid, maleic anhydride and itaconic acid.

When the alkali-soluble resin that can be used in the present invention is a homopolymer or copolymer of a polymerizable monomer having a phenolic hydroxyl group, a polymerizable monomer having a sulfonamide group, or a polymerizable monomer having an active imide group, Those having an average molecular weight of 2,000 or more and a number average molecular weight of 500 or more are preferred. 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. .
In particular, when the alkali-soluble resin that can be used in the present invention is a phenol formaldehyde resin or a cresol aldehyde resin, the weight average molecular weight is 500 to 20,000, and the number average molecular weight is 200 to 10,000. Those are preferred.

  The alkali-soluble resin that can be used in the present invention, that is, a resin other than the polyamide resin according to the present invention is used in an addition amount of 70% by mass or less of the total composition.

  In the photosensitive composition of the present invention, it is preferable to add cyclic acid anhydrides, phenols, and organic acids in order to increase sensitivity. As cyclic acid anhydrides, as described in U.S. Pat. No. 4,115,128, phthalic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, 3,6-endooxy-Δ4-tetrahydrophthalic anhydride Acid, tetrachlorophthalic anhydride, maleic anhydride, chloromaleic anhydride, α-phenylmaleic anhydride, succinic anhydride, pyromellitic anhydride, and the like.

  Examples of phenols include bisphenol A, p-nitrophenol, p-ethoxyphenol, 2,3,4-trihydroxybenzophenone, 4-hydroxybenzophenone, 2,4,4′-trihydroxybenzophenone, 4,4,4 ″. -Trihydroxy-triphenylmethane, 4,4 ', 3 ", 4" -tetrahydroxy-3,5,3', 5'-tetramethyltriphenylmethane and the like.

  Organic acids are described in JP-A-60-88942 and JP-A-2-96755. There are sulfonic acids, sulfinic acids, alkylsulfuric acids, phosphonic acids, phosphinic acids, phosphate esters, carboxylic acids, etc., specifically, p-toluenesulfonic acid, dodecylbenzenesulfonic acid, p-toluenesulfinic acid, ethyl Sulfuric acid, phenylphosphonic acid, phenylphosphinic acid, phenyl phosphate, diphenyl phosphate, benzoic acid, isophthalic acid, adipic acid, p-toluic acid, 3,4-dimethoxybenzoic acid, phthalic acid, terephthalic acid, 1,4- Examples include cyclohexene-2,2-dicarboxylic acid, erucic acid, lauric acid, n-undecanoic acid, and ascorbic acid.

The proportion of the cyclic acid anhydrides, phenols, and organic acids in the photosensitive composition is preferably 0.05 to 15% by mass, and more preferably 0.1 to 5% by mass.
Further, in the photosensitive composition of the present invention, in order to widen the development latitude, nonionic surface activity as described in JP-A-62-251740 and JP-A-4-68355 is used. 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 polyoxyethylene polyoxypropylene block polymer, sorbitan tristearate, sorbitan monopalmitate, sorbitan trioleate, stearic acid monoglyceride, polyoxyethylene sorbitan monooleate, polyoxyethylene nonyl Specific examples of amphoteric surfactants include alkyldi (aminoethyl) glycine, alkylpolyaminoethylglycine hydrochloride, Amorgen K (trade name, manufactured by Daiichi Kogyo Co., Ltd., N-tetradecyl-N). N-betaine type), 2-alkyl-N-carboxyethyl-N-hydroxyethyl imidazolinium betaine, Levon 15 (trade name, manufactured by Sanyo Kasei Co., Ltd., alkyl imidazoline series) and the like. Among these, it is particularly preferable to add a polyoxyethylene polyoxypropylene block polymer.
The proportion of the nonionic surfactant and the amphoteric surfactant in the photosensitive composition is preferably 0.05% to 15% by mass, more preferably 0.1 to 5% by mass.

  In the photosensitive composition in the present invention, a printing out agent for obtaining a visible image immediately after exposure, a dye as an image coloring agent, other fillers, and the like can be added. Typical examples of the printing-out agent for obtaining a visible image immediately after exposure include a combination of a photosensitive compound that releases an acid upon exposure 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 and 36223, 54-74728, 60-3626, 61-143748, 61-151644, 63-58440 and combinations of salt-forming organic dyes I can give you.

Such trihalomethyl compounds include oxadiazole compounds and triazine compounds, both of which are excellent in stability over time and give clear printout images, but with an oxide film amount of 1.0 g / m ² or more. The residual color after development is particularly deteriorated in the photosensitive lithographic printing plate using the body. The present invention is particularly effective when a photosensitive composition containing such a compound is used, and a lithographic printing plate having almost no residual color can be obtained. In addition to the salt-forming organic dyes described above, other dyes can also be used as the image colorant. Examples of suitable dyes including salt-forming organic dyes include oil-soluble dyes and basic dyes. Specifically, oil yellow # 101, oil yellow # 130, oil pink # 312, oil green BG, oil blue BOS, oil blue # 603, oil black BY, oil black BS, oil black T-505 (or more, Orient Chemical Pure Co., Ltd.) Victoria Pure Blue, Crystal Violet (CI 42555), Ethyl Violet (CI 42600), Methyl Violet (CI 42535), Rhodamine B (CI 45170B), Malachite Green (CI 42000), Methylene Blue (CI 522015), etc. . The dyes described in JP-A-62-293247 are particularly preferred.

The photosensitive composition in the present invention is dissolved in a solvent that dissolves each of the above components and coated on a support. Solvents used here include γ-butyrolactone, ethylene dichloride, cyclohexanone, methyl ethyl ketone, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, 2-methoxyethyl acetate, 1-methoxy-2-propanol, 1-methoxy-2- Propyl acetate, toluene, ethyl acetate, methyl lactate, ethyl lactate, dimethyl sulfoxide, dimethylacetamide, dimethylformamide, water, N-methylpyrrolidone, tetrahydrofurfuryl alcohol, acetone, diacetone alcohol, methanol, ethanol, isopropanol, diethylene glycol dimethyl ether, etc. These solvents are used alone or in combination. And the density | concentration (solid content) in the said component is 2-50 mass%. The coating amount varies depending on the use, but for example, a photosensitive lithographic printing plate generally has a solid content of preferably 0.5 to 3.0 g / m ² . Photosensitivity increases as the coating amount decreases, but the physical properties of the photosensitive film decrease.

  In the photosensitive composition of 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 mass of the total photosensitive composition, more preferably 0.05 to 0.5% by mass.

  When producing a lithographic printing plate using the photosensitive composition of the present invention, the support is preferably an aluminum plate. Aluminum plates include pure aluminum and aluminum alloy plates. Various aluminum alloys can be used. For example, an alloy of aluminum such as silicon, copper, manganese, magnesium, chromium, zinc, lead, bismuth, nickel and the like is used. These compositions contain some iron and titanium as well as other negligible amounts of impurities.

  The aluminum plate is surface-treated as necessary. For example, a surface treatment such as graining treatment, sodium silicate, potassium fluoride zirconate, an immersion treatment in an aqueous solution of phosphate, or an anodizing treatment is preferably performed. Further, as described in US Pat. No. 2,714,066, an aluminum plate which has been grained and then dipped in an aqueous sodium silicate solution is disclosed in US Pat. No. 3,181,461. As described above, an aluminum plate that has been anodized and then immersed in an aqueous solution of an alkali metal silicate is also preferably used. The anodizing treatment may be carried out by using, for example, an inorganic acid such as phosphoric acid, chromic acid, sulfuric acid or boric acid, an organic acid such as oxalic acid or sulfamic acid, or an aqueous solution or a non-aqueous solution of these salts alone or in combination of two or more. It is carried out by passing an electric current using an aluminum plate as an anode.

  Silicate electrodeposition as described in US Pat. No. 3,658,662 is also effective. These hydrophilization treatments are performed to make the surface of the support hydrophilic, in order to prevent harmful reactions with the photosensitive composition provided thereon, and to improve adhesion to the photosensitive layer. It is given to improve.

  Prior to graining the aluminum plate, the surface may be pretreated if necessary to remove the rolling oil on the surface and expose a clean aluminum surface. For the former, a solvent such as trichlene, a surfactant or the like is used. For the latter, a method using an alkali / etching agent such as sodium hydroxide or potassium hydroxide is widely used.

As the graining method, any of mechanical, chemical and electrochemical methods is effective. Examples of the mechanical method include a ball polishing method, a blast polishing method, a brush polishing method in which an aqueous dispersion slurry of an abrasive such as pumice is rubbed with a nylon brush, and a chemical method is disclosed in JP-A No. 54-31187. A method of immersing in a saturated aqueous solution of an aluminum salt of a mineral acid as described in the publication is suitable, and as an electrochemical method, a method of alternating current electrolysis in an acidic electrolyte such as hydrochloric acid, nitric acid or a combination thereof Is preferred. Among such surface roughening methods, in particular, a surface roughening method combining mechanical surface roughening and electrochemical surface roughening as described in JP-A-55-137993, This is preferable because of its strong adhesion to the support.
The graining by the method as described above is preferably performed in such a range that the center line average surface roughness (Ra) of the surface of the aluminum plate is 0.3 to 1.0 μm.

  The grained aluminum plate is washed with water and chemically etched as necessary. The etching treatment liquid is usually selected from an aqueous solution of a base or acid that dissolves aluminum. In this case, a film different from aluminum derived from the etching solution component should not be formed on the etched surface. Examples of preferable etching agents include sodium hydroxide, potassium hydroxide, trisodium phosphate, disodium phosphate, tripotassium phosphate, dipotassium phosphate, etc. as basic substances; sulfuric acid, persulfuric acid as acidic substances Phosphoric acid, hydrochloric acid and salts thereof, and the like, but metals such as zinc, chromium, cobalt, nickel, and copper, which have a lower ionization tendency than aluminum, are not preferable because an unnecessary film is formed on the etched surface.

These etching agents are most preferably used so that the dissolution rate of the aluminum or alloy to be used is from 0.3 g to 40 g / m ² per immersion time in setting the concentration and temperature to be used. It can be above or below this. Etching is performed by immersing an aluminum plate in the above etching solution or by applying an etching solution to the aluminum plate, and the etching amount is processed in a range of 0.5 to 10 g / m ^2. Is preferred.

  As the etching agent, an aqueous base solution is preferably used because of its high etching rate. In this case, since a smut is generated, a normal desmut process is performed. As the acid used for the desmut treatment, nitric acid, sulfuric acid, phosphoric acid, chromic acid, hydrofluoric acid, hydrofluoric acid, and the like are used.

  The etched aluminum plate is washed with water and anodized as necessary. Anodization can be performed by a method conventionally used in this field. Specifically, when direct current or alternating current is applied to aluminum in an aqueous solution or non-aqueous solution of sulfuric acid, phosphoric acid, chromic acid, oxalic acid, sulfamic acid, benzenesulfonic acid, etc., or a combination of two or more thereof, aluminum support An anodized film can be formed on the body surface.

Since the anodizing treatment conditions vary depending on the electrolyte used, it cannot be determined unconditionally, but in general, the concentration of the electrolyte is 1 to 80% by mass, the solution temperature is 5 to 70 ° C., and the current density is 0.7. A range of 5 to 60 amperes / dm ² , a voltage of 1 to 100 V, and an electrolysis time of 30 seconds to 50 minutes is appropriate. Among these anodizing treatments, a method of anodizing at a high current density in sulfuric acid described in British Patent No. 1,412,768 is disclosed in US Pat. No. 4,211,619. The method of anodizing in a low concentration sulfuric acid as described and the method of anodizing phosphoric acid as an electrolytic bath described in US Pat. No. 3,511,661 are preferred.

  The aluminum plate roughened and further anodized as described above may be subjected to a hydrophilic treatment as necessary, and preferred examples thereof include US Pat. Nos. 2,714,066 and 3,181. 461, for example, an aqueous solution of sodium silicate or potassium fluoride zirconate disclosed in Japanese Patent Publication No. 36-22063 and disclosed in US Pat. No. 4,153,461 There is a method of treating with polyvinyl sulfonic acid as described above.

In addition, an undercoat layer made of a water-soluble compound can be provided on an aluminum plate that has been roughened, anodized as described above, and further subjected to a hydrophilic treatment as necessary. Examples of such water-soluble compounds include combinations of water-soluble metal salts and hydrophilic cellulose disclosed in JP-B-57-16349 (for example, zinc chloride and carboxymethyl cellulose, magnesium chloride and hydroxyethyl cellulose, etc.), US Polyacrylamide disclosed in Japanese Patent No. 3,511,661, polyvinylphosphonic acid disclosed in Japanese Patent Publication No. 46-35685, amino acids disclosed in Japanese Patent Laid-Open No. 60-149491, and salts thereof (Alkali metal salts such as Na salts and K salts, ammonium salts, hydrochlorides, oxalates, acetates, phosphates, etc.), amines having a hydroxyl group disclosed in JP-A-60-232998 and the like Salts (hydrochlorides, oxalates, phosphates, etc.), and further disclosed in JP-A-63-165183 A compound having an amino group and a phosphonic acid group or a salt thereof, and (a) amino group and (b) one phosphonic acid group, phosphinic acid group, or phosphoric acid group disclosed in JP-A-3-261592 Examples thereof include compounds or salts thereof, aliphatic or aromatic phosphonic acids or phosphinic acids or salts thereof disclosed in JP-A-5-246171. Of these, the compounds disclosed in JP-A-3-261592 and JP-A-5-246171 are particularly preferred. Such water-soluble primer layer compounds preferably provided in the range of 1mg / m ² ~80mg / m ² in solid content.

  The surface of the photosensitive layer provided as described above is preferably matted in order to shorten the time for evacuation during close contact exposure using a vacuum firing frame and prevent blurring. Specifically, a method for providing a mat layer as described in JP-A-50-125805, JP-B-57-6582, and JP-A-61-2986, and JP-B-62-62337. And a method of thermally fusing the solid powder as described above.

  The developer for the photosensitive composition of the present invention is preferably an alkaline aqueous solution substantially free of an organic solvent, specifically, sodium silicate, potassium silicate, sodium hydroxide, potassium hydroxide, lithium hydroxide, third Aqueous solutions such as sodium phosphate, dibasic sodium phosphate, tribasic ammonium phosphate, dibasic ammonium phosphate, sodium metasilicate, sodium carbonate, sodium bicarbonate, potassium carbonate, potassium bicarbonate, aqueous ammonia are suitable. And added so that the concentration thereof is 0.1 to 10% by mass, preferably 0.5 to 5% by mass.

Among these, developers containing alkali silicates such as potassium silicate, lithium silicate, sodium silicate and the like are preferable because they do not easily stain during printing, and the composition of the alkali silicate is [SiO ₂ ] / [M] = 0.5 to 2.5 (wherein [SiO ₂ ] and [M] represent the molar concentration of SiO _{2 and} the molar concentration of total alkali metal, respectively), and SiO ₂ is 0.5. A developer containing 8 to 8% by mass is preferably used. Further, for example, water-soluble sulfites such as sodium sulfite, potassium sulfite, and magnesium sulfite, resorcin, methylresorcin, hydroquinone, thiosalicylic acid, and the like can be added to the developer. The preferable content of these compounds in the developer is 0.002 to 4% by mass, and preferably 0.01 to 1% by mass.

  In the developer, anionic surfactants and amphoteric surfactants described in JP-A-50-51324 and JP-A-59-84241, JP-A-59-75255, By incorporating at least one of nonionic surfactants as described in JP-A-60-111246 and JP-A-60-213943, or JP-A-55-95946, 50- As described in JP-A-142528, by containing a polymer electrolyte, it is possible to increase wettability to a photosensitive composition and to improve development stability (development latitude), which is preferably used. . The amount of the surfactant added is preferably 0.001 to 2% by mass, particularly preferably 0.003 to 0.5% by mass.

Further, it is preferable that the alkali metal of the alkali silicate contains 20 mol% or more of potassium in the total alkali metal, because insoluble matter is less generated in the developer, more preferably 90 mol% or more, and most preferably 100 mol%. This is the case.
Further, in the developer used in the present invention, some organic solvents such as alcohol, chelating agents described in JP-A No. 58-190952, and those described in JP-B-1-30139 are used. Antifoaming agents such as metal salts and organic silane compounds can be added.

  Further, as a so-called “non-silicate developer” which does not contain an alkali silicate and contains a non-reducing sugar and a base, a developer described in JP-A-8-305039 is suitable. This developer contains (a) at least one saccharide selected from non-reducing sugars (for example, D-sorbite) and (b) at least one base, and has a pH in the range of 9.0 to 13.5. When the photosensitive lithographic printing plate is developed using this developer, the surface of the photosensitive layer is not deteriorated and the inking property of the photosensitive layer is maintained in a better state. be able to.

As the developer used in the present invention, a developer described in JP-A-6-282079 can also be used. This is because 5 mol or more of ethylene oxide is added to an alkali metal silicate having a molar ratio of SiO ₂ / M ₂ O (M represents an alkali metal) of 0.5 to 2.0 and a sugar alcohol having 4 or more hydroxyl groups. A developer containing a water-soluble ethylene oxide addition compound obtained in this manner.

  Examples of the light source used for exposure include a carbon arc lamp, a mercury lamp, a xenon lamp, a tungsten lamp, and a metal halide lamp.

  A photosensitive lithographic printing plate using the photosensitive composition of the present invention is subjected to plate making treatment by the methods described in JP-A Nos. 54-8002, 55-11545, and 59-58431. Needless to say. That is, after the development treatment, washing may be followed by desensitization treatment, or a desensitization treatment as it is, treatment with an aqueous solution containing an acid, or desensitization treatment after treatment with an aqueous solution containing an acid. Further, in the development process of this type of photosensitive lithographic printing plate, an alkaline aqueous solution is consumed depending on the processing amount and the alkali concentration is reduced, or the alkali concentration is reduced by air due to long-time operation of the automatic developer. In this case, the processing capacity is lowered, and the processing capacity may be recovered by using a replenisher as described in JP-A No. 54-62004. In this case, it is preferable to replenish by the method described in US Pat. No. 4,882,246. The plate making process as described above is preferably carried out by an automatic developing machine as described in JP-A-2-7054 and JP-A-2-32357.

  In addition, in the case where an unnecessary image portion is erased after imagewise exposure, development, washing with water or rinsing of a photosensitive lithographic printing plate using the photosensitive composition of the present invention, Japanese Patent Publication No. 2-13293. It is preferable to use an erasing solution as described in the publication. Further, as a desensitized gum to be applied as desired in the final step of the plate making process, JP-B-62-16834, JP-A-62-25118, JP-A-63-52600, JP-A-62-7595, JP-A-62-116993 are used. Nos. 62-83194 are preferred.

  Furthermore, in the case where the photosensitive lithographic printing plate using the photosensitive composition of the present invention is image-exposed, developed, washed or rinsed, erased if necessary, and washed after washing, In addition, it is preferable to treat with a surface-adjusting solution as described in JP-B Nos. 61-2518, 55-28062, JP-A Nos. 62-31859 and 61-159655.

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 specific polyamide resin]
<Synthesis Example 1>
Using 8.826 g of 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride and 6.007 g of 4,4′-diaminodiphenyl ether in 70 g of 1,4-dioxane and 30 g of DMF at a temperature of 50 ° C. for 6 hours. Then, polymerization was performed at normal pressure to prepare a specific polyimide precursor solution (1) containing the specific polyamide resin (1).
The specific polyimide precursor concentration of the specific polyimide precursor solution (1) is 13.0%, the logarithmic viscosity of the specific polyimide precursor is 1.91 (0.5 g / 100 ml N-methylpyrrolidone, 25 ° C.), and the specific polyimide precursor The solution had a rotational viscosity (25 ° C.) of 1800 cps and a molecular weight of 30,000. In addition, the molecular weight was measured using a polystyrene standard substance using GPC.

<Synthesis Example 2>
9.667 g of 3,3 ′, 4,4′-benzophenonetetracarboxylic dianhydride and 3.007 g of 4,4′-diaminodiphenyl ether, 1.32 tetraethylenediamine, 40 g of 1,4-dioxane, 20 g of DMF, A specific polyimide precursor solution (2) containing the specific polyamide resin (2) was prepared by polymerization at 40 ° C. in ethanol at 25 ° C. and 14.5 hours at normal pressure.
The specific polyimide precursor concentration of the specific polyimide precursor solution (2) is 10.0%, the logarithmic viscosity of the specific polyimide precursor is 1.03 (0.5 g / 100 ml N-methylpyrrolidone, 25 ° C.), and the specific polyimide precursor The rotational viscosity (25 ° C.) of the solution was 12000 cps, and the molecular weight was 70,000. In addition, the molecular weight was measured using a polystyrene standard substance using GPC.
The structure of the specific polyamide resin obtained in Synthesis Examples 1 and 2 is shown below.

[Examples 1 to 4 and Comparative Examples 1 to 5]
The surface of an aluminum plate having a thickness of 0.30 mm was grained using a nylon brush and a 400 mesh Pamiston water suspension, and then thoroughly washed with water. After etching by dipping in a 10% sodium hydroxide solution at 70 ° C. for 60 seconds, it was washed with running water, neutralized with 20% HNO ₃ , and washed with water. This was subjected to an electrolytic surface roughening treatment in a 1% nitric acid aqueous solution with an anode self-electricity of 160 coulomb / dm ² using a sinusoidal alternating waveform current under the condition of VA = 12.7V. When the surface roughness was measured, it was 0.6 μm (Ra indication). Subsequently, after being immersed in a 30% aqueous solution of H ₂ SO _{4 and} desmutted at 55 ° C. for 2 minutes, the thickness in the aqueous solution of 20% H ₂ SO ₄ is 2.4 g / m ² at a current density of 2 A / dm ² . The substrate was prepared by anodizing as described above.
An undercoat liquid (A) having the following composition was applied to the surface of the substrate thus treated and dried at 80 ° C. for 30 seconds. The coating amount after drying was 30 mg / m ² .

このようにして基板（I）を作成した。 Undercoat liquid (A)

In this way, a substrate (I) was prepared.

Next, 25 ml / m ² of the following photosensitive solutions (B) and (C) are coated on the substrate (I) by rod coating, dried at 150 ° C. for 1 minute, and positive photosensitive lithographic printing plate [B ] -1 to [B] -5 and [C] -1 to [C] -4 were obtained. The coating amount after drying was about 1.5 g / m ² .

Photosensitive solution (B)

Photosensitive solution (C)

  A positive transparent original image of a line image and a halftone dot image is brought into close contact with the photosensitive layers of the photosensitive lithographic printing plates [B] -1 to 5 and [C] -1 to 4, and an image is taken for 1 minute from a distance of 1 m by a 3 KW metal halide lamp. Exposed. The exposed photosensitive lithographic printing plates [B] -1 to 5 and [C] -1 to 4 are diluted with DP-4 (trade name: manufactured by Fuji Photo Film Co., Ltd.) in an 8-fold diluted aqueous solution at 25 ° C. for 40 seconds. Development was performed with an automatic developing machine (1300 V: manufactured by Fuji Photo Film Co., Ltd.), and a 2-fold diluted aqueous solution of FP-2W (trade name: Finishing Gum manufactured by Fuji Photo Film Co., Ltd.) was applied.

The resulting lithographic printing plates [B] -1 to 5 and [C] -1 to 4 were used to print on high-quality paper using a commercially available normal ink and UV ink with a KOR printer manufactured by Heidelberg. The final printing number of the planographic printing plates [B] -1 to [5] and [C] -1 to 4 and the stain on the printed matter were examined. The “dirt” was evaluated visually, and “good” was evaluated as “good”, and “x” was evaluated when there was severe dirt.
As can be seen from Table 1, lithographic printing plates [B] -1 to 2 and [C] -1 to 2 (Examples 1 to 4) using the polymer compound of the present invention have [B] -3, [ C] -3, [C] -4, [B] -4, and [B] -5 (Comparative Examples 1 to 5), when using either normal ink or UV ink, the number of printed sheets is large. It was very excellent in printing durability and excellent in dirt performance.

Table 1

Examples 5-8, Comparative Examples 6-10
The same experiment as in Examples 1 to 4 and Comparative Examples 1 to 5 was performed except that the following substrate (II) was used instead of the substrate (I) used in Examples 1 to 4 and Comparative Examples 1 to 5. As a result, similar results were obtained.

<Production of substrate (II)>
An aluminum plate (material: JIS A 1050) having a thickness of 0.3 mm is etched for 10 seconds at a caustic soda concentration of 30 g / l, an aluminum ion concentration of 10 g / l, a liquid temperature of 60 ° C., washed with running water, and washed with 10 g / l nitric acid. After neutralizing and washing with water. Using an alternating current of a sine wave under the condition of applied voltage Va = 20 V, an electric current of 500 C / dm ² in an aqueous solution having a hydrogen chloride concentration of 15 g / l, an aluminum ion concentration of 10 g / l, and a liquid temperature of 30 ° C. The surface was subjected to an electrochemical surface roughening treatment in an amount and washed with water, followed by an etching treatment for 10 seconds at a caustic soda concentration of 30 g / l, an aluminum ion concentration of 10 g / l and a liquid temperature of 40 ° C., and then washed with running water. Next, it was desmutted in a sulfuric acid aqueous solution having a sulfuric acid concentration of 15% by mass and a liquid temperature of 30 ° C., and washed with water. Furthermore, in a 10% by weight sulfuric acid aqueous solution with a liquid temperature of 20 ° C., anodization was performed under a condition of a current density of 6 A / dm ² by direct current so that the amount of the anodized film was 2.5 g / m ^2. , Dried. Then, it processed for 10 second at 30 degreeC with the sodium silicate 1.0 weight% aqueous solution, and produced the board | substrate. The centerline average roughness (Ra) of the substrate was measured using a needle having a diameter of 2 μm and found to be 0.48 μm.

On the silicate-treated aluminum substrate obtained as described above, an undercoat liquid (D) having the following composition was applied and dried at 80 ° C. for 15 seconds to form a coating film. The coating amount of the coating film after drying was 17 mg / m ² .

Undercoat liquid (D)

  In Examples 1 to 8 and Comparative Examples 1 to 10, the same results were obtained even when the following developer A containing no silicate was used instead of the developer; DP-4.

<Developer A>
-D-sorbitol 2.5 parts by mass-Sodium hydroxide 0.85 parts by mass-Polyethylene glycol lauryl ether 0.5 parts by mass (weight average molecular weight 1,000)
・ Pionine C-158-G (manufactured by Takemoto Yushi Co., Ltd.) 0.02 parts by mass, water 70 parts by mass

Claims (1)

A photosensitive composition comprising a polyamide resin containing a structural unit represented by the following general formula (I), water-insoluble and alkali-soluble, and o-naphthoquinonediazide.

In formula (I), R ¹ represents an optionally substituted linking group having at least one aromatic ring, and each of the two —COOH is directly bonded to the aromatic ring. R ² represents an alkylene group, an arylene group or an aralkylene group which may have a substituent.