JP2639722B2 - Photosensitive composition - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a photosensitive composition suitable for a photosensitive lithographic printing plate, and more particularly to a photocrosslinkable photosensitive composition soluble in an alkaline aqueous solution. .

[Prior art and problems to be solved] Photocrosslinkable materials that are crosslinked by a cycloaddition reaction are well known, and these are photosensitive lithographic printing plates, and photosensitive compositions used in the production of photoresists and the like. Used as a major component. Among these crosslinkable materials, photocrosslinkable polymers having a maleimide group in the side chain are partially used for high sensitivity, and have a carboxylic acid group on the side chain for the purpose of solubilization in an alkaline aqueous solution. Are also known.

However, when a polymer having a carboxylic acid group is coated on a support having an anodic oxide film provided on an aluminum substrate, the adsorbed carboxylic acid group-containing polymer remains on the anodic oxide film (aluminum oxide) after development. However, there has been a problem that a non-image portion is stained during printing. Further, since the carboxylic acid group-containing polymer is very easily swelled in an alkaline aqueous solution, there have been problems such as poor chemical resistance, abrasion resistance and scratch resistance of the image area.

[Object of the invention]

Therefore, an object of the present invention is to develop with an alkaline developer, and have excellent chemical resistance, friction resistance and scratch resistance,
In addition, it is an object of the present invention to provide a lithographic printing plate photosensitive composition that does not cause stains on non-image areas.

Another object of the present invention is to provide a negative type lithographic printing plate photosensitive composition which can be developed with a positive type lithographic printing plate developer, that is, a developing solution mainly composed of silicate.

It is a further object of the present invention to provide a photosensitive composition for a lithographic printing plate which has high sensitivity and high printing durability and can be developed even with a developer containing no organic solvent.

[Configuration of the invention]

The present inventors have conducted intensive studies to achieve the above object, and as a result, as a photosensitive composition, (1) at least one or more photodimerizable maleimide groups on the side chain and at least one or more alkaline aqueous solution Dissociable pKa is 6-12
The above object is achieved by using a photosensitive compound containing a polymer compound soluble in an alkaline aqueous solution having an acid group (hereinafter, referred to as a polymer compound of the present invention) and (2) a photosensitizer. That is, the present invention has been made.

 Hereinafter, the present invention will be described in detail.

The polymer compound of the present invention has the following general formula (A)
Having a maleimide group represented by

(Wherein R ¹ and R ² are each a hydrogen atom, a halogen atom,
It represents an alkyl group, and R ¹ and R ² may together form a 5- or 6-membered ring. The alkyl group of R ¹ and R ² preferably has 1 to 4 carbon atoms, and particularly preferably is a methyl group. Also, as a halogen atom,
Chlorine, bromine and iodine are preferred. ) The polymer compound of the present invention has, for example, the general formulas (B) to (D): (Wherein, R ¹ and R ² have the same meanings as described above, n represents an integer, preferably 1 to 6.) and a pK which can be dissociated in a molecule with an alkaline aqueous solution.
a can be obtained by polymerizing a monomer having an acid group of 6 to 12 with a known polymerization initiator in a suitable solvent.

Examples of the acid group having a pKa of 6 to 12 that can be dissociated in an alkaline aqueous solution include groups represented by the following formula.

−CONHCO− …… (F) Among the specific monomers containing a functional group represented by the general formula (F), those preferably used in the present invention include N-
An acryloyl acrylamide and a methacrylic acid derivative and an acrylic acid derivative having a -CO-NH-CO- group.
Examples of such methacrylic acid derivatives and acrylic acid derivatives include N-acetyl methacrylamide, N-propionyl methacrylamide, N-butanoyl methacrylamide, N-pentanoyl methacrylamide, N-decanoyl methacrylamide, N-dodeca Noyl methacrylamide, N-benzoyl methacrylamide, N- (p
Methacrylamide derivatives such as -methylbenzoyl) methacrylamide, N- (p-chlorobenzoyl) methacrylamide, N- (naphthylcarbonyl) methacrylamide, N- (phenylacetyl) methacrylamide, and 4-methacryloylaminophthalimide; There are acrylamide derivatives having similar substituents.

These monomers are disclosed in European Patent No. 0140273,
It is synthesized by the method described in -115597 and the like.

Among the monomers containing a functional group represented by the general formula (G), specific ones preferably used in the present invention include:
It is a monomer represented by the following general formula (G-1).

In the formula, R ⁷ represents a hydrogen or a methyl group.

R ⁸ represents hydrogen or a C _{1 to} C ₁₂ alkyl group, cycloalkyl group, aryl group or aralkyl group which may have a substituent.

R ⁹ represents a single bond or a C _{1 to} C ₁₂ alkylene group, cycloalkylene group, arylene group or aralkylene group which may have a substituent.

X ² represents a phenylene group or a naphthylene group which may have a substituent.

Examples of the compound represented by the general formula (G-1) include N- (p-hydroxyphenyl) methacrylamide, N- (2- (p-hydroxyphenyl) ethyl) methacrylamide, and N- (1- (5 Methacrylamide derivatives such as -hydroxy) naphthyl) methacrylamide; and acrylamide derivatives having the same substituents as described above. These compounds are synthesized by the method described in JP-A-62-279327.

In the polymer compound of the present invention, the acid groups represented by the general formulas (F) and (G) can be introduced by a known polymer reaction, but it is difficult to control the amount of the introduction. However, this is not preferred in the present invention.

The polymer compound of the present invention may be a multi-component copolymer obtained by polymerization in the presence of a vinyl monomer different from the above monomers.

Such vinyl monomers different from the above monomers include, for example, acrylic acid, methacrylic acid, acrylic esters, acrylamides, methacrylic esters, methacrylamides, allyl compounds, vinyl ethers, vinyl esters, styrenes And compounds having a polymerizable unsaturated bond selected from croton esters and the like.

As a solvent used when synthesizing the polymer compound of the present invention, for example, ethylene dichloride, cyclohexanone, methyl ethyl ketone, acetone, methanol, ethanol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, 2-methoxyethyl acetate, 1-methoxyethyl acetate Methoxy-2-propanol, 1-
Methoxy-2-propyl acetate, N, N-dimethylformamide, N, N-dimethylacetamide, toluene,
Examples include ethyl acetate, methyl lactate, ethyl lactate, and dimethyl sulfoxide.

These solvents are used alone or as a mixture of two or more.

The polymer compound of the present invention has an average of two or more maleimide groups per molecule on the side chain, and preferably has a weight average molecular weight of 1,000 or more, and more preferably 10,000 to 300,000. The polymer compound of the present invention preferably contains a maleimide group as a copolymer component in a molar ratio of 20% or more, and more preferably 30% to 90%.

Further, the pKa that can be dissolved in an alkaline aqueous solution is 6/12.
Monomer having an acid group of 10% or more, preferably 15% or more
It is contained at 70%. If this component is too small, the solubility in an alkaline aqueous solution is insufficient. If it is too large, the strength of the image area is deteriorated and the sensitivity is lowered.

The content of the polymer compound of the present invention is 10 to 99% by weight, preferably 50 to 95% based on the photosensitive composition.

In the present invention, a photosensitizer can be contained as needed. As the photosensitizer, it is preferable to use a triplet sensitizer having a maximum absorption that allows practically sufficient light absorption in a range of 300 nm or more. Examples of such a sensitizer include thioxane, thioxanthone derivatives, for example, 2-chlorothioxanthone, 2-isopropylthioxanthone, dimethylthioxanthone, methylthioxanthone-1-ethylcarboxylate, and 5-nitroacenaphthene. . In addition, 1,2-dicyanobenzene, chloranil, described in JP-A-59-206425,
Electron accepting compounds such as 2,3-diclo-5,6-dicyanobenzoquinone are also effective. In addition, benzothiazole dyes and naphthothiazole dyes, for example, dyes represented by the following formulas are also effective.

(R ₁ represents a substituted or unsubstituted alkyl group, R ₂ or R ₃ ; a hydrogen atom or a substituted or unsubstituted aryl group represents a heterocyclic group.) The amount of these sensitizers to be added to the total composition It is preferably from 1 to 20%, more preferably from 3 to 10%.

In addition to the above, a diazo resin having a negative action can be added as needed. Such diazo resins include 4-diazo-diphenylamine, 1-diazo-4-N,
N-dimethylaminobenzene, 1-diazo-4-N, N-diethylaminobenzene, 1-diazo-4-N-ethyl-
N-hydroxyethylaminobenzene, 1-diazo-4
-N-methyl-N-hydroxyethylaminobenzene,
1-diazo-2,5-diethoxy-4-benzoylaminobenzene, 1-diazo-4-N-benzylaminobenzene, 1-diazo-4-N, N-dimethylaminobenzene,
1-diazo-4-morpholinobenzene, 1-diazo-
2,5-dimethoxy-4-p-tolylmercaptobenzene, 1-diazo-2-ethoxy-4-N, N-dimethylaminobenzene, p-diazo-dimethylaniline, 1-diazo-2,5-dibutoxy-4 -Morpholinobenzene,
1-diazo-2,5-diethoxy-4-morpholinobenzene, 1-diazo-2,5-dimethoxy-4-morpholinobenzene, 1-diazo-2,5-diethoxy-4-morpholinobenzene, 1-diazo-2,5-diethoxy-4-morpholinobenzene Diazo-2,5-diethoxy-4
-P-tolylmercaptobenzene, 1-diazo-3-ethoxy-4-N-methyl-N-benzylaminobenzene, 1-diazo-3-chloro-4-N, N-diethylaminobenzene, 1-diazo-3- Methyl-4-pyrrolidinobenzene, 1-diazo-2-chloro-4-N, N-dimethylamino-5-methoxybenzene, 1-diazo-3-methoxy-4-pyrrolidinobenzene, 3-methoxy-4-
Diazo monomers such as diazodiphenylamine, 3-ethoxy-4-diazodiphenylamine, 3- (n-propoxy) -4-diazophenylamine, 3-isopropoxy-4-diazophenylamine, formaldehyde, acetaldehyde, propionaldehyde, Butyl acetaldehyde, isobutyraldehyde, or a condensing agent such as benzaldehyde in a molar ratio of 1: 1 to 1: 0.5, respectively.
The ratio is preferably set to 1: 0.8 to 0.6, and a reaction product of a condensate obtained by condensing this with a usual method and an anion is exemplified. As anions, tetrafluoroboric acid, hexafluorophosphoric acid, triisopropylnaphthalenesulfonic acid, 5-nitroortho-toluenesulfonic acid, 5-sulfosalicylic acid, 2,5-dimethylbenzenesulfonic acid, 2,4,6- Trimethylbenzenesulfonic acid, 2-nitrobenzenesulfonic acid, 3-chlorobenzenesulfonic acid, 3-bromobenzenesulfonic acid, 2-fluorocaprylnaphthalenesulfonic acid, dodecylbenzenesulfonic acid, 1-naphthol-
5-sulfonic acid, 2-methoxy-4-hydroxy-5-
Benzoyl-benzenesulfonic acid, paratoluenesulfonic acid and the like can be mentioned. Among them, alkyl aromatic sulfonic acids such as hexafluorophosphoric acid, triisopropylnaphthalenesulfonic acid and 2,5-dimethylbenzenesulfonic acid are particularly preferable.

The addition amount of these diazo resins to the entire composition is 0.1 to
1.5% is preferable, and 0.3 to 5% is more preferable.

In the composition of the present invention, in addition to the polymer compound of the present invention, a known alkali-soluble polymer such as phenol formaldehyde resin, cresol formaldehyde resin, phenol-modified xylene resin, polyhydroxystyrene, and polyhalogenated hydroxystyrene. Compounds can be included. Such an alkali-soluble polymer compound is used in an amount of 70% by weight or less of the total composition.

In addition to the above, it is preferable to further add a thermal polymerization inhibitor to the photosensitive composition, for example, hydroquinone, p-methoxyphenol, di-t-butyl-p-cresol,
Pyrogallol, t-butylcatechol, benzoquinone,
4,4'-thiobis (3-methyl-6-t-butylphenol), 2,2'-methylenebis (4-methyl-6-t-
Butylphenol) and 2-mercaptobenzimidazole are useful, and in some cases, a dye or pigment or a pH indicator or the like as a printing agent can be added for the purpose of coloring the photosensitive layer.

Representative examples of the printing-out agent include a combination of a photosensitive compound that releases an acid upon exposure and an organic dye that can form a salt.

Further, phosphoric acid, phosphorous acid, tartaric acid, citric acid, malic acid, dipicolinic acid, polynuclear aromatic sulfonic acids and salts thereof, sulfosalicylic acid, and the like can be added as needed as stabilizers for the diazo resin.

The photosensitive composition as described above is, for example, 2-methoxyethanol, 2-methoxyethyl acetate, propylene glycol monomethyl ether, 3-methoxypropanol, 3-methoxypropyl acetate, methyl ethyl ketone, N, N-dimethylformamide, N, N -Dissolve in a suitable solvent alone such as dimethylacetamide, dimethylsulfoxide, ethylene dichloride or a mixture thereof in an appropriate combination, and coat on a support. The coating amount in the range of about 0.1 g / m ² ~ about 10 g / m ² in weight after drying are suitable, preferably from 0.5 to 5 g / m ^2.

When a lithographic printing plate is produced 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, and for example, an alloy of aluminum with a metal such as silicon, copper, manganese, magnesium, chromium, zinc, lead, bismuth, or nickel is used. These compositions also contain some negligible amount of impurities in addition to some iron and titanium.

The aluminum plate is subjected to a surface treatment as required. For example, surface treatment such as graining treatment, immersion treatment in an aqueous solution of sodium silicate, potassium fluorozirconate, phosphate, or the like, or anodic oxidation treatment is preferably performed. Further, as described in U.S. Pat.No. 2,714,066, an aluminum plate grained and then immersed in an aqueous solution of sodium silicate, and an anodized aluminum plate as described in U.S. Pat. Those which are immersed in an aqueous solution of an alkali metal silicate after the treatment are also preferably used. The anodizing treatment is, for example, an inorganic acid such as phosphoric acid, chromic acid, sulfuric acid, boric acid,
Alternatively, the method is carried out by passing a current using an aluminum plate as an anode in an electrolytic solution of an organic acid such as oxalic acid or sulfamic acid or a salt thereof or an aqueous solution or a non-aqueous solution alone or in combination of two or more.

Also, silicate electrodeposition as described in US Pat. No. 3,658,662 is effective.

These hydrophilic treatments are performed not only to make the surface of the support hydrophilic, but also to prevent harmful reactions with the photosensitive composition provided thereon and to improve the adhesion with the photosensitive layer. It is done to improve.

Prior to graining the aluminum plate, if necessary, the surface may be subjected to a pretreatment to remove rolling oil on the surface and to expose a clean aluminum surface. For the former, solvents such as trichlene, surfactants and the like are 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, and a brush polishing method in which a water-dispersed slurry of an abrasive such as pumice is rubbed with a nylon brush.
A method of immersing in a saturated aqueous solution of an aluminum salt of a mineral acid as described in -31187 is suitable, and as an electrochemical method, an alternating current is carried out in an acidic electrolyte such as hydrochloric acid, nitric acid or a combination thereof. Electrolysis is preferred. Among such surface roughening methods, particularly, a surface roughening method combining mechanical surface roughening and electrochemical surface roughening as described in JP-A-55-137793 discloses oil-sensitive images. Is preferred because of its strong adhesion to the support.

The graining by the above-described method is preferably performed in such a range that the center line surface roughness (Ha) of the surface of the aluminum plate is 0.3 to 1.0 μ.

The aluminum plate thus grained is washed with water and chemically etched as required.

The etching solution is usually selected from aqueous solutions of bases or acids that dissolve aluminum. In this case, a film different from aluminum derived from the etchant component must not be formed on the etched surface. Preferred examples of the etching agent include sodium hydroxide, potassium hydroxide, trisodium phosphate, disodium phosphate, tripotassium phosphate, dipotassium phosphate as basic substances; and sulfuric acid, persulfuric acid, phosphoric acid, hydrochloric acid as acidic substances. And salts thereof, such as metals such as zinc, chromium, cobalt, nickel and copper, which have a lower ionization tendency than aluminum, are not preferred because they form unnecessary coatings on the etched surface.

It is most preferable that these etching agents are used so that the dissolution rate of the aluminum or alloy to be used is 0.3 to 40 g / m ² per one minute of immersion time, at the setting of the working concentration and the temperature. Or it may be lower.

The etching is performed by immersing the aluminum plate in the above-mentioned etching solution or by applying the etching solution to the aluminum plate, and is preferably processed so that the etching amount is in the range of 0.5 to 10 g / m ² .

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

The etched aluminum plate is optionally washed with water and anodized. The anodic oxidation can be performed by a method conventionally used in this field. Specifically, nitric acid, phosphoric acid, chromic acid, oxalic acid, sulfamic acid,
When a direct current or an alternating current is applied to aluminum in an aqueous solution or a non-aqueous solution in which benzenesulfonic acid or the like or a combination of two or more thereof is formed, an anodic oxide film can be formed on the surface of the aluminum support.

Anodizing treatment conditions vary depending on the electrolytic solution used, and thus cannot be unconditionally determined. Generally, however, the concentration of the electrolytic solution is 1 to 80% by weight, the liquid temperature is 5 to 70 ° C, and the current density is 0%. .
A range of 5 to 60 A / 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, in particular, British Patent No. 1,
The method of anodic oxidation at high current density in sulfuric acid described in 412,768 and the method of anodic oxidation using phosphoric acid as an electrolytic bath described in US Pat. No. 3,511,661 are preferred.

The aluminum plate which has been roughened as described above and further anodized may be subjected to a hydrophilizing treatment as necessary. Preferred examples thereof include U.S. Pat. Nos. 2,714,066 and
Alkali metal silicates such as those disclosed in U.S. Pat.
There is a method of treating with potassium fluorozirconate disclosed in 22063 and polyvinyl sulfonic acid as disclosed in US Pat. No. 4,153,461.

Furthermore, after these treatments, the resin in the aqueous solution, for example, polymers and copolymers having a polyacrylic acid or sulfonic acid group in the side chain, other low-molecular-weight compounds soluble in an alkaline aqueous solution, salts of triethanolamine, and alanine compounds Is also preferred.

As a developer for the photosensitive composition of the present invention, sodium silicate, potassium silicate, sodium hydroxide, potassium hydroxide, lithium hydroxide, sodium tertiary phosphate, sodium diphosphate, tertiary ammonium phosphate, ammonium diphosphate An aqueous solution of an inorganic alkali agent such as sodium metasilicate, sodium bicarbonate, aqueous ammonia, etc. is suitable, and their concentration is 0.1 to 10% by weight, preferably 0.5% by weight.
-5% by weight.

In addition, an organic solvent such as a surfactant or alcohol can be added to the alkaline aqueous solution as needed. Preferred examples of the organic solvent include benzyl alcohol, 2-phenoxyethanol, 2-butoxyethanol, and n-propyl alcohol. Furthermore,
Mention may be made of those described in U.S. Pat. Nos. 3,475,171 and 3,615,480. Further, JP-A-50-26
The developing solutions described in JP-A-601, JP-B-56-39464 and JP-B-56-42860 are also excellent as developers for printing plates using the photosensitive composition of the present invention.

〔The invention's effect〕

The photosensitive composition of the present invention has high sensitivity and can be developed with an alkaline aqueous solution, and when used as a printing plate, has excellent abrasion resistance and scratch resistance, and does not easily cause stain on a non-image area.

〔Example〕

Hereinafter, the present invention will be described in more detail with reference to Synthesis Examples and Examples, but the present invention is not limited thereto.

Synthesis Example 1 (Reference Example) 43.0 g (0.5 mole) of methacrylic acid, 50.6 g (0.5 mole) of triethylamine and 150 ml of tetrahydrofuran were placed in a 500-ml three-necked flask equipped with a stirrer, a cooling tube and a dropping funnel.
And stirred at room temperature. To this mixture, a mixture of 98.6 g (0.5 mole) of p-toluenesulfonyl isocyanate and 50 ml of tetrahydrofuran was dropped by a dropping funnel over about 1 hour. After completion of the dropwise addition, the mixture was stirred for 2 hours while attaching an oil bath and heating to reflux. After the completion of the reaction, the mixture was poured into water 3 with stirring, and acidified with hydrochloric acid. The precipitate was collected by filtration, washed well with a funnel, and then redispersed in water 1. 50 g of sodium bicarbonate was gradually added to this dispersion. The insolubles were filtered off, and the filtrate was acidified by adding hydrochloric acid. The precipitate was collected by filtration, washed well with a funnel, and dried to obtain 61 g of N- (p-methylphenylsulfonyl) methacrylamide (pKa7).

Next, 36.6 g (0.20 mole) of N- (3-hydroxypropyl) dimethylmaleimide and 22 ml of triethylamine were placed in a 500 ml three-necked flask equipped with a stirrer, a condenser, and a dropping funnel.
3 g (0.22 mole) and 200 ml of diethyl ether were added, and the mixture was stirred in an ice-water bath. To this mixture is added methacrylic acid chloride 2
2.0 g (0.21 mole) was added dropwise from the dropping funnel over about 1 hour. After dropping, remove the ice-water bath and leave at room temperature for 2 hours.
Stirred for hours. After the completion of the reaction, the precipitate was separated by filtration and put into a separating funnel. The ether solution was washed with an aqueous solution of hydrochloric acid, an aqueous solution of sodium carbonate and water in that order, and dried over sodium sulfate. After sodium sulfate was filtered off, the mixture was concentrated under reduced pressure to obtain 39 g of N- (3-methacryloxypropyl) dimethylmaleimide.

Subsequently, 14.4 g (0.06 mole) of N- (p-methylphenylsulfonyl) methacrylamide and 35.2 g of N- (3-methacryloxypropyl) dimethylmaleimide were placed in a 300 ml three-necked flask equipped with a stirrer and a condenser. 0.14mole),
115 g of 2-methoxyethanol and 2,2 as a polymerization initiator
2'-azobis (2,4-dimethylvaleronitrile) (V-
65) (Wako Pure Chemical Industries, Ltd.) (0.497 g, 0.002 mole) was added, and the mixture was stirred for 5 hours while heating to 65 ° C. in an oil bath under a stream of N ₂ . After the completion of the reaction, the mixture was poured into water 1 with stirring, and the precipitate was filtered and dried to obtain 45 g of a white solid. According to gel permeation chromatography, the weight average molecular weight (polystyrene standard) of this polymer compound was 45,0
00. (Reference polymer compound (a)).

Synthesis Examples 2 and 3 In a three-necked flask equipped with a condenser and a stirrer, 80 ml of methanol, 134 ml of concentrated hydrochloric acid and 4-nitrophthalimide 38.
4 g (0.2 mole) was added and stirred at room temperature. To this reaction mixture, 33.9 g (0.607 mole) of iron powder was added little by little over 1 hour. (At this time, the temperature in the flask rose and the solvent refluxed.) After the iron powder was added, the temperature in the flask decreased.
Stirring was continued until the temperature reached 30 ° C. After the completion of the reaction, this mixture was poured into water 1.4 with stirring, and stirred for 30 minutes. The precipitate was taken out by filtration, further washed well with water 1, and dried to obtain a yellow solid of 4-aminostarimide (yield: 29.5 g).

Next, equipped with a cooling tube, a stirrer, a dropping funnel, 200 ml
16.2 g of 4-aminophthalimide (0.1mo
le) and pyridine (80 ml) were added, and the mixture was stirred in an ice-water bath. To this mixture, 10.5 g (mole) of methacrylic acid chloride was added dropwise over 1 hour using a dropping funnel.

After dropping, remove the ice water bath and equip oil bath.
The mixture was stirred for 2 hours while heating to ° C. After completion of the reaction, the mixture was poured into water 1 with stirring, acidified with hydrochloric acid, and further stirred for 30 minutes. The precipitate was filtered and dried to obtain (pK) of 4- (methacryloylamino) phthalimide.
The yellow solid of a9) was obtained. This solid was purified by recrystallization from a mixed solvent of ethanol and water (yield 1).
0.3g).

Further, in the same manner as in Synthesis Example 1, polymer compounds (g) and (h) of the present invention shown in Table 1 were synthesized. The molecular weights of these polymer compounds were 47,000 and 52,000, respectively.

Synthesis Examples 4 and 5 p-Hydroxymethacrylanilide (pKa1) was prepared by the method described in the synthesis example of JP-A-62-279327.
0) was synthesized.

Next, polymer compounds (i) and (j) of the present invention shown in Table 1 were synthesized in the same manner as in Synthesis Example 1. The molecular weights of these polymer compounds were 22,000 and 28,000, respectively.

Example 1 A 0.30 mm thick aluminum plate was coated with a nylon brush and 400
The surface was sand-grained using an aqueous suspension of mesh pumistone, and then thoroughly washed with water. After etching by dipping in 10% sodium hydroxide at 70 ° C. for 60 seconds, the substrate was washed with running water, neutralized with 20% NHO ₃ and washed with water. This was subjected to electrolytic surface roughening treatment in a 1% nitric acid aqueous solution at an anode electricity of 160 clones / dm ² using a sine wave alternating current under the condition of _VA = 12.7V. The surface roughness was measured to be 0.6μ (Ra
Display). Subsequently, after being immersed in a 30% H ₂ SO ₄ aqueous solution and desmutted at 55 ° C. for 2 minutes, the thickness was increased to 2.7 g / m ² at a current density of 2 A / dm ² in a 20% H ₂ SO ₄ aqueous solution. Anodizing was performed as follows.

Next, by changing the type of the polymer compound of the present invention in the following photosensitive solution [A], two kinds of photosensitive solutions [A] -2 to [A]-
3 was adjusted.

Photosensitive solution [A] -1 (Reference example)-5 g of polymer compound of Synthesis example (a)-0.4 g of sensitizer represented by the following structural formula ・ Plasticizer 10% dispersion of copper phthalocyanine pigment (CI Pigment Blue 15) 1.0 g ・ F-177 (fluorinated nonionic surfactant manufactured by Dainippon Ink and Chemicals, Inc.) 0.02 g ・ Methyl ethyl ketone 20 ・ Methanol 5 ・ Ethylene glycol monomethyl ether 40 Photosensitive solution [A] -2 • 5 g of polymer compound of Synthesis example (h) • 0.3 g of sensitizer represented by the following structural formula Photosensitive solution [A] -3 • 5 g of polymer compound of Synthesis Example (i) • 0.3 g of sensitizer represented by the following structural formula 0.1 g of PF ₆ salt of formaldehyde condensate of p-diazodiphenylamine (otherwise the same as [A] -1) Comparative Example 1 The following structural formula was used in place of the polymer compound of the present invention in photosensitive solution [A] -1. The photosensitive solution [B] was prepared using the compound represented by the formula (1).

These photosensitive solutions [A] -2 to [A] -3 and [B] were applied on the aluminum support using a spin coater to a thickness of 1.5 g / m ² after drying. Dry at 80 ° C. for 2 minutes.

The lithographic printing plates thus obtained were designated as lithographic printing plates [A] -2 to [A] -3 and [B], respectively.

Exposure was performed by applying a step wedge (density difference 0.15, number of density steps: 15) and a halftone negative original image on the prepared sample using a vacuum furnace, and irradiating with a 2KW ultra-high pressure mercury lamp for 20 seconds. It was immersed in a 5 wt% aqueous solution for about 1 minute and developed. After washing with water and drying, the obtained lithographic printing plates [A] -2 to 3 and [B] were subjected to Heidelberg KOR-
Printing was performed using a D-type printing machine.

The sensitivity and printing performance of the developer for the printing plate were as shown in Table 2 below.

 ──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-52-988 (JP, A) JP-A-55-160010 (JP, A) JP-A-62-78544 (JP, A) JP-A 62-78544 294238 (JP, A) JP-A-63-137923 (JP, A) JP-A-2-157762 (JP, A)

Claims (1)

(57) [Claims] (1) An alkaline aqueous solution having at least one or more photodimerizable maleimide group on a side chain and an acid group having a pKa of 6 to 12 that can be dissociated with at least one or more alkaline aqueous solution. A soluble polymer compound, and (2) a photosensitizer, wherein the acid group is -CONHCO- (I) or A photosensitive composition comprising: