JP2639734B2 - Photosensitive composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a photosensitive composition suitably used for producing a lithographic printing plate, an IC circuit, a photomask, and the like. The present invention relates to an improved novel photosensitive composition.

[Conventional technology and problems to be solved]

Photocrosslinkable materials that are crosslinked by a cycloaddition reaction are well known, and they are widely used as a main component of a photosensitive composition used for producing a photosensitive lithographic printing plate or the like. Among them, a polymer compound having a maleimide group in a side chain as a photocrosslinkable polymer compound, a cinnamyl group having a photodimerizable unsaturated double bond adjacent to an aromatic nucleus,
A polymer compound having a cinnamylidene group, a chalcone group or the like in a side chain or a main chain is useful, and a polymer compound having a maleimide group is particularly useful in that sensitivity is high.

Examples of the photosensitive composition containing such a polymer compound containing a maleimide group include JP-A-52-988 and JP-A-52-988.
No. 3055, the composition described in the publication of JP 55-160010 and the like, but none of the photosensitive compositions have sufficient sensitivity, a sufficient image with a short exposure time However, there was a drawback that no

Therefore, an object of the present invention is to provide a highly sensitive negative photosensitive composition capable of forming a sufficient image even with a short exposure time.

[Means for solving the problem]

The present inventors have conducted intensive studies to achieve the above object, and as a result, have found that the above object can be easily achieved by using a novel photosensitive composition, and have reached the present invention.

That is, the present invention provides a photocrosslinkable group represented by the following general formula (I): (Wherein, R ¹ and R ² each represent a hydrogen atom, a halogen atom, an alkyl group or an aryl group, or R ¹ and R ²
May together form a ring. The present invention relates to a photosensitive composition comprising a microgel having the following formula:

 Hereinafter, the present invention will be described in detail.

In the general formula (I), the preferred R ¹ and R ² are each a hydrogen atom, a chlorine atom, a bromine atom, an alkyl group, a phenyl group which may have a substituent C ₁ -C _6, R ¹ ,
R ² may together form a ring.

In the present invention, the microgel refers to a spherical high molecular compound having a crosslinked structure and having a diameter of 0.01 to 1 μm, and is formed by emulsion polymerization or the like. For the preparation and use of microgels, see, for example, UK Patent No. 967,051 and US Patent No. 38950.
This is described in Japanese Patent Publication No. 82.

The microgel having a photocrosslinkable group represented by the general formula (I) preferably used in the present invention is prepared by emulsion polymerization or dispersion polymerization using compounds of the following groups A and B and, if necessary, compounds of group C. Are synthesized by

Group A: Compound having a photocrosslinkable group represented by the general formula (I) and a polymerizable ethylenically unsaturated bond (10 to 99 mol%) Examples of such a compound preferably used in the present invention include the following. Compounds of (Wherein, R ¹ and R ² have the same meaning as described above. R ³ and R ⁴
Represents a hydrogen atom or -CH _3, X represents a -0- or -NH-. n ¹ ~n ⁹ is an integer of 1 or more. Also, compounds described in JP-A-52-988 and the like are preferable.

Group B: Compound having two or more polymerizable ethylenically unsaturated bonds (crosslinking agent, 1 to 50 mol%) Examples of such a compound suitably used in the present invention include ethylene glycol dimethacrylate,
Examples include methacrylic acid derivatives such as butanediol dimethacrylate, trimethylolpropane trimethacrylate, and methylenebismethacrylamide, and acrylic acid derivatives having the same substituents as described above, and styrene derivatives such as divinylbenzene.

Group C: Other compounds having a polymerizable ethylenically unsaturated bond (0 to 80 mol%) Examples of such compounds suitably used in the present invention include methacrylic esters, acrylic esters, and methacrylic esters. Acid amides, acrylamides,
Styrenes, acrylonitrile, methacrylonitrile and the like can be mentioned.

In addition, when performing dispersion polymerization, it is preferable to use a macromer or the like in which the terminal of the polyester oligomer is a methacrylic acid ester or an acrylic acid ester.

The microgel of the present invention can be obtained by emulsion polymerization or dispersion polymerization, and these polymerization methods are described in US Pat. No. 3,895,082, British Patent No. 967,051, and IMMUNOLOGICAL COMMUNICAT.
IONS), 12 (5) 509-517 (1983), and many others.

In the case of synthesizing a microgel by emulsion polymerization, it is usually necessary to convert the microgel into a dried powder before preparing the photosensitive composition. Known techniques of flocculation, filtration, washing and drying can be used for this purpose. Alternatively, a dispersion of an organic solvent can be obtained by using an appropriate organic solvent (for example, toluene or the like) without azeotropic distillation to obtain a powder from an aqueous dispersion of a microgel.

The use amount of the microgel of the present invention is 5 to 95% by weight, preferably 10 to 90% by weight based on the total weight of the photopolymerizable composition.

Since the photosensitive composition using the microgel obtained as described above does not have a suitable alkali-soluble group in the microgel, a developer for developing after exposure will use an organic solvent. . However, from the viewpoint of occupational safety and health, it is preferable to use an aqueous alkaline developer at the time of development, and this is achieved by introducing an acid group having a pKa value of 14 or less into the microgel.

Such a microgel used in the present invention is synthesized by emulsion polymerization or dispersion polymerization using the following compounds of Group D and the above-mentioned compounds of Groups A, B and C.

Group D: Compound having a polymerizable ethylenically unsaturated bond and an acid group having a pKa value of 14 or less (1 to 80 mol%) In the present invention, the acid group having a pKa value of 14 or less preferably used is For example, -SO ₃ H, —COOH, —CONHSO ₂ —, —CONHCO—, —SO ₂ NH—, phenolic —OH, —COCH ₂ COO— and the like.

Examples of such a compound suitably used in the present invention include, for example, methacrylic acid, acrylic acid, 3- (2-
(Methacryloyloxyethoxycarbonyl) propionic acid, N- (2-sulfo-1,1-dimethylethyl) methacrylamide, N- (phenylsulfonyl) methacrylamide, N- (p-sulfamoylphenyl) methacrylamide, N- ( methacrylic acid derivatives such as (p-hydroxyphenyl) methacrylamide and 2-acetoacetoxyethyl methacrylate, acrylic acid derivatives having the same substituents as described above, maleimides, styrene derivatives such as p-vinylbenzenesulfonic acid, and EP115410A2 and the like. The compounds described are mentioned.

The photosensitive composition of the present invention can contain a photosensitizer as needed.

As the photosensitizer, a triplet sensitizer having a maximum absorption that allows practically sufficient light absorption in a range of 300 nm or more is preferable.

Preferred triplet sensitizers include benzophenone derivatives, benzanthrone derivatives, quinones, aromatic nitro compounds, naphthothiazoline derivatives, benzothiazoline derivatives, thioxanthones, naphthothiazole derivatives, ketocoumarin compounds, benzothiazole derivatives, benzodithiol derivatives, naphthofuranone Compounds, pyrylium salts, thiapyrylium salts and the like can be mentioned. Specifically, Michler's ketone, N, N'-diethylaminobenzophenone, benzanthrone, (3-methyl-1,3-diaza-1,9-benz) anthrone picramide, 5-nitroacenaphthene, 2-chlorothioxanthone, -Isopropylthioxanthone, dimethylthioxanthone, methylthioxanthone-1-ethylcarboxylate, 2
-Nitrofluorene, 2-dibenzoylmethylene-3-
Methylnaphthothiazoline, 3,3-carbonyl-bis (7
-Diethylaminocoumarin), 2,4,6-triphenylthiapyrylium perchlorate, 2- (p-chlorobenzoyl) naphthothiazole, 2- (5-t-butyl-1,3
-Benzodithiol-2-ylidene) -1,3-diethylthiobarbituric acid; The addition amount of these sensitizers is 1 to 20% by weight of the total composition, preferably 3 to 10% by weight.

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-diazodiphenylamine, formaldehyde, acetaldehyde, propionaldehyde, butyl Aldehyde, isobutyraldehyde, a condensing agent such as benzaldehyde in a molar ratio of 1: 1 to 1: 0.5, preferably 1: 0.8 to 1: 0.6, and a condensate obtained by condensing this in a usual manner. Reaction products with anions are included. Examples of anions include tetrafluoroboric acid, hexafluorophosphoric acid, triisopropylnaphthalenesulfonic acid, 5-nitroorthotoluenesulfonic 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,
Examples thereof include dodecylbenzenesulfonic acid, 1-naphthol-5-sulfonic acid, 2-methoxy-4-hydroxy-5-benzoyl-benzenesulfonic acid, and paratoluenesulfonic acid. Of these, hexafluorophosphoric acid, triisopropylnaphthalenesulfonic acid and 2,2
Alkyl aromatic sulfonic acids such as 5-dimethylbenzenesulfonic acid are preferred.

A reaction product of the above-mentioned diazo monomer, a condensate obtained from an aldehyde having a carboxylic acid and / or phenol or an acetal thereof (and, if necessary, the above-mentioned condensing agent) and the above-mentioned anion, −102456
And diazo resins described in JP-A-1-102457 are also suitably used in the present invention.

The amount of these diazo resins added to the total composition is generally
It is preferably from 0.1 to 15% by weight, more preferably from 0.3 to 5% by weight.

Further, these diazo resins can be used as an intermediate layer between the photosensitive layer and the support.

The photosensitive composition of the present invention further includes, for example,
No. 52-988, a known alkali-soluble polymer compound such as phenol formaldehyde resin, cresol formaldehyde resin, phenol-modified xylene resin, polyhydroxystyrene, and polyhalogenated hydroxystyrene. Can be. Such an alkali-soluble polymer compound is used in an amount of 70% by weight or less of the total composition.

Further, the photosensitive composition of the present invention preferably contains a thermal polymerization inhibitor, 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), 2-mercaptobenzimidazole and the like are useful, and in some cases, a pH indicator or the like can be added as a dye or pigment or a printing agent for the purpose of coloring the photosensitive layer.

Representative examples of the printing-out agent include a combination of a photosensitive compound which releases an acid upon exposure to light and an organic dye which forms a salt and liquefies.

Further, as a stabilizer for the diazo resin, 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 necessary. .

Further, the photosensitive composition of the present invention may contain a plasticizer and the like. As the plasticizer, dialkyl phthalate such as dibutyl phthalate and dihexyl phthalate, oligoethylene glycol alkyl ester, phosphate plasticizer and the like can be used.

The photosensitive composition of the present invention includes, for example, 2-methoxyethanol, 2-methoxyethyl acetate, propylene glycol monomethyl ether, 3-methoxypropanol, 3-methoxypropyl acetate, methyl ethyl ketone, N, N-dimethylformamide, N, N -Dissolved or dispersed in a suitable solvent such as dimethylacetamide, dimethylsulfoxide, ethylene dichloride, methyl lactate, ethyl lactate alone or a mixture thereof in an appropriate combination, and coated on a support. The coating amount is 0.
1 g / m ² range to 10 g / m ² are suitable, preferably 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 a metal such as silicon, copper, manganese, magnesium, chromium, zinc, lead, bismuth, and nickel and aluminum 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, U.S. Pat.
As described in the specification, an aluminum plate subjected to an anodizing treatment and then immersed in an aqueous solution of an alkali metal silicate is also preferably used. The anodizing treatment, for example, phosphoric acid, chromic acid, sulfuric acid, an inorganic acid such as boric acid, or oxalic acid, an organic acid such as sulfamic acid or an aqueous solution or a non-aqueous solution of these salts alone or in combination of two or more. This is carried out by flowing a current in an electrolyte using aluminum as an anode.

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

These hydrophilization 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 applied 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 a range where the center line surface roughness (Ra) of the surface of the aluminum plate is 0.3 to 1.0 μm.

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, and dipotassium phosphate as basic substances; and sulfuric acid and persulfuric acid as acidic substances. , Phosphoric acid, hydrochloric acid, and salts thereof. Metals having a lower ionization tendency than aluminum, such as salts of zinc, chromium, cobalt, nickel, and copper, are not preferable because they form unnecessary films 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 in setting the working concentration and the temperature. It can be below or below.

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, when direct current or alternating current is passed through aluminum in an aqueous solution or a non-aqueous solution in which sulfuric acid, phosphoric acid, chromic acid, oxalic acid, sulfamic acid, benzenesulfonic acid, or the like or a combination of two or more thereof, aluminum An anodized film can be formed on the surface of the 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. 1,41
The method of anodizing with high current density in sulfuric acid described in US Pat. No. 2,768 and the method of anodizing 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 hydrophilization treatment if necessary. Preferred examples thereof are U.S. Pat. Nos. 2,714,066 and 3,1.
Alkali metal silicates, such as those disclosed in U.S. Pat.
There is a method of treating with potassium fluorozirconate disclosed in U.S. Pat.

Furthermore, after these treatments, water-soluble resins, such as polymers and copolymers having polyacrylic acid and sulfonic acid groups in the side chains, other low-molecular weight compounds soluble in alkaline aqueous solutions, salts of triethanolamine, and alanine A primer coated with a compound is also suitable.

The photosensitive composition of the present invention coated on a support is exposed through a transparent original having a line image, a halftone dot image, and the like, and then developed with an aqueous alkaline developer to form a negative relief image on the original. give.

Examples of the light source used for exposure include a carbon arc lamp, a mercury lamp, a xenon lamp, a metal halide lamp, a strobe, ultraviolet rays, a laser beam, and the like.

〔The invention's effect〕

The photosensitive composition of the present invention has excellent sensitivity at the time of image exposure,
A sufficient image can be obtained even with a short exposure time. Therefore, work efficiency and the like are significantly improved.

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 In a flask equipped with a stirrer and a condenser, 126 g (1 mole) of 2,3-dimethylmaleic anhydride, 131 g (1 mole) of 6-aminocaproic acid and 4600 ml of toluene were added, and heated at 100 ° C. for 1 hour. Stirred. Next, a Dean-Stark water separator was attached, and the mixture was stirred for 3 hours while removing water under reflux of toluene. After the reaction was completed, the mixture was cooled, and hexane 1.
It was broken into 5. The resulting solid was further reslurried in water 1.5 by filtration and drying. By filtration and drying, 231 g of the following compound (i) as a white solid was obtained.

Next, 57.4 g (0.24 mole) of compound (i) and 29.7 g of thionyl chloride were placed in a 300 ml flask equipped with a stirrer and a condenser.
(0.25 mole) and stirred at room temperature for 1 hour. In addition, 80
The mixture was stirred for 1 hour while being heated to ° C. After the completion of the reaction, the mixture was cooled and 150 ml of ether was added. Next, a dropping funnel was attached to the flask, and while cooling the reaction mixture in an ice-water bath,
26.0 g (0.2 mole) of 2-hydroxyethyl methacrylate
A mixture of pyridine and 31.6 g (0.4 mole) of pyridine was dropped by a dropping funnel over about 30 minutes. After completion of the dropwise addition, the mixture was stirred for 1 hour in an ice-water bath, and further stirred for 2 hours while heating to 50 ° C. After completion of the reaction, the reaction mixture was cooled, and the reaction mixture was put into a separating funnel together with 400 ml of ethyl acetate. Washing was performed in the order of water, 1N hydrochloric acid, water, a saturated aqueous solution of sodium hydrogen carbonate, and water. After this solution was dried over sodium sulfate, the solvent was distilled off under reduced pressure to obtain 59 g of a liquid of the following compound (ii).

Next, 68.52 g (0.195 mole) of compound (ii), 2.97 g (0.015 mole) of ethylene glycol dimethacrylate, 20.72 g of hydrogen (2-methacryloyloxy) ethyl hydrogen succinate were placed in a flask equipped with a stirrer and a condenser. (0.09mol
e), 9.22 g of sodium dodecyl sulfate and 800 ml of water were added, and heated to 50 ° C. under a nitrogen stream. 0.58 g of potassium persulfate and 0.54 g of sodium thiosulfate pentahydrate were added to this mixed solution, and the mixture was stirred for 5 hours. After completion of the reaction, salting out and centrifugation were performed, followed by drying under reduced pressure to obtain 85 g of a white powder (microgel (p) of the present invention). The spherical shape of the powder particles was confirmed by microscope.

Synthesis Examples 2 to 5 In the same manner as in Synthesis Example 1, the microgels (q) to (t) of the present invention shown in Table 1 below were synthesized.

Example 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, then neutralized and washed with 20% HNO ₃ , and washed with water. This was subjected to electrolytic surface roughening treatment in a 1% nitric acid aqueous solution at an anode charge of 160 clones / dm ² using an alternating waveform current of a sine solution under the condition of V _A = 12.7 V. The surface roughness was measured to be 0.6μ (Ra
Display). Subsequently, the plate was immersed in a 30% H ₂ SO ₄ aqueous solution to desmutting 2 minutes at _{55 ℃, 20% H 2 SO} 4
In an aqueous solution, anodizing was performed for 2 minutes so that the thickness became 2.7 g / m ² at a current density of 2 A / dm ² .

The following photosensitive solutions [V] -1 to [V] -5 were applied to the aluminum plate obtained as described above using a wheeler and dried at 80 ° C. for 2 minutes. Dry weight was 1.5 g / m ^2.

Table 2 shows the microgels used in the present invention used in the photosensitive solutions [V] -1 to [V] -5. Next, as a comparative example, a photosensitive solution [W] using the following polymer compound (having no cross-linked structure) instead of the microgel of the present invention in the above photosensitive solution [V] was simultaneously applied and dried. .

Comparative polymer compound: Fuji photographic film on the respective photosensitive lithographic printing plates [V] -1 to [V] -5 and [W] obtained using the photosensitive solutions [V] -1 to [V] -5 and [W]. Lay the gray scale tablets from Co., Ltd. on top and expose them with a bar key printer (Ico Adalx 2KW) manufactured by Barkey Technical Co., Ltd., immerse them in the following developer at room temperature for 50 seconds, lightly rub the surface with absorbent cotton to remove unexposed areas did.

The sensitivity of the obtained lithographic printing plate to the amount of exposure was visually read from the number of solid portions. Table 2 shows the results. From these results, the photosensitive lithographic printing plates [V] -1 to [V] -5 using the microgel of the present invention have a greater number of steps than the photosensitive lithographic printing plates [W] of Comparative Examples, and have high sensitivity. there were.

Claims (1)

(57) [Claims] 1. A photocrosslinkable group represented by the following general formula (I): (However, in the formula, R ¹ and R ² each represent a hydrogen atom, a halogen atom, an alkyl group or an aryl group, or R ¹ and R ² may be combined to form a ring.) (1) a compound having a photocrosslinkable group represented by the general formula (I) and a polymerizable ethylenically unsaturated bond,
(2) a crosslinking agent having two or more polymerizable ethylenically unsaturated bonds, 1 to 50 mole%, (3) a polymerizable ethylenically unsaturated bond and a pKa value of 1
Emulsion polymerization or dispersion of a compound having an acid group of 4 or less, 1 to 80 mol%, and (4) optionally, a compound having another polymerizable ethylenically unsaturated bond, 0 to 80 mol%. A photosensitive composition containing a microgel obtained by assembling.