JP4667211B2 - Photopolymerizable composition and photosensitive lithographic printing plate material - Google Patents

Description

  The present invention relates to a negative photosensitive composition, and further to a photosensitive lithographic printing plate material using the same. More specifically, the present invention relates to a photopolymerizable composition and a photosensitive lithographic printing plate material capable of forming an image using a scanning exposure apparatus using a light source such as a near infrared laser emitting near 830 nm.

  Conventionally, photopolymerization systems consisting of a photopolymerization initiator, a binder resin, and various polyfunctional acrylate monomers and oligomers have been used as photopolymerizable compositions. These are generally inhibited by oxygen in which polymerization is dissolved. In order to prevent this, it was necessary to provide an oxygen blocking layer such as polyvinyl alcohol on the upper part of the layer for photopolymerization. On the other hand, as clarified in Japanese Patent Laid-Open No. 2001-290271 (Patent Document 1) by the present inventor, a polymer having a styrenic unsaturated bond in the side chain, or two or more styrenes in the molecule It has been found that the use of a compound having a polymerizable unsaturated bond makes the polymerization less susceptible to dissolved oxygen and gives a highly sensitive photopolymerizable composition without using an oxygen blocking layer.

  The system introduced with the above styrenic unsaturated bond surely gives a photopolymerizable composition having high sensitivity and high contrast, and even when such a system is used as a lithographic printing plate material, it is sufficient under normal printing conditions. As a result, it has been found that a printing plate having printing durability can be provided. However, as various performance requirements have accumulated in the market, it has been found that sufficient performance has not been achieved. Among them, typical problems are as follows: 1. Insufficient resistance to various chemicals When developing with a low pH alkaline developer, the problem that stains are likely to occur in the non-image area due to the remaining film has emerged as a particularly important problem.

  In particular, in a negative photosensitive composition, in order to improve developability, it is usual to use a binder resin that is highly soluble in an alkaline aqueous solution. There has been a problem that it is inferior in chemical resistance, such as being easily damaged by an ink washing solvent and a plate cleaner used during printing.

In order to satisfy both of the above problems 1 and 2, in order to improve developability and chemical resistance, the non-image area exhibits good developability, and the image area further increases the crosslinking density. Therefore, it is a condition to improve chemical resistance, and the present condition is that materials and means for realizing such performance are desired.
JP 2001-290271 A

  The object of the present invention is that when a negative photopolymerizable composition using a scanning exposure apparatus using a laser emitting in the near infrared region (700 to 900 nm) is used, the resistance to various chemicals is good. In addition, when developing with a low pH alkaline developer, a photopolymerizable composition is provided in which the remaining film hardly causes stains on the non-image area.

The above object of the present invention, have a structural unit represented by the general formalized 1 in the molecule, and the addition of polyethyleneimine, polyallylamine, and any of the compounds selected from Polydiallylamine 2-methacryloyloxyethyl isocyanate This is basically solved by using a photopolymerizable composition characterized by containing a compound obtained by the above.

R ₁ and R ₂ each represent a hydrogen atom or an arbitrary group. A represents an alkylene group having 1 to 4 carbon atoms.

  According to the present invention, in a negative photopolymerizable composition using a scanning exposure apparatus using a laser emitting light in the near infrared region (700 to 900 nm), light having good developability and excellent chemical resistance. A polymerizable composition is obtained. Furthermore, a lithographic printing plate excellent in developability and chemical resistance can be obtained by using a lithographic printing plate material using the same.

  Hereinafter, the present invention will be described in detail. The photopolymerizable composition according to the present invention means a system containing a photopolymerization initiator for initiating polymerization by light irradiation and further containing a compound having a structural unit represented by Chemical Formula 1 in the molecule.

  The compound having a structural unit represented by Chemical Formula 1 specifically corresponds to any compound as long as it has a structure in which a methacryloyloxy group bonded to an alkylene group is bonded via a urea bond. Although the intended effect is recognized, in order to exert the maximum effect, a compound having an optimum structure is selected in each photopolymerization system, and a combination of a plurality of compounds is preferably used. An example of the preferred compound is shown in Chemical Formula 2. A synthesis example of the compound represented by M-1 in Chemical Formula 2 is shown in Synthesis Example 1 described later.

  In addition to the compounds shown above, a more preferred example is a case where the compound is a compound obtained by adding 2-methacryloyloxyethyl isocyanate to polyethyleneimine. Polyethyleneimine as used herein refers to a variety of commercially available polyethyleneimines that are used as raw materials. The molecular weight, molecular weight distribution, degree of branching, and ethyleneimine repeating units are included depending on the polyethyleneimine production method. Those having different ratios of tertiary amine and tertiary amine can be used. The molecular weight may be a low-molecular oligomer of about 100 to 1000, or a molecular weight exceeding tens of thousands to hundreds of thousands can be used. The proportion of the ethyleneimine structure contained in the repeating unit is particularly preferably about 30% or more in the structure, but as a typical polyethyleneimine commercially available, the amine ratio is primary (% ): Grade 2 (%): Grade 3 (%) in the range of 20 to 50:30 to 60:20 to 30 can be used very preferably. When such a commercially available polyethyleneimine is used, in the reaction with 2-methacryloyloxyethyl isocyanate, 1 equivalent of 2-methacryloyloxyethyl isocyanate is added to the primary amine moiety and secondary amine moiety, and tertiary It is preferable to carry out the reaction by adding an amount of 2-methacryloyloxyethyl isocyanate calculated so that the amine moiety remains unreacted, but an excess of 2-methacryloyloxyethyl isocyanate is added or intentionally added. It is also preferable to carry out the reaction by adding an equal amount or less of 2-methacryloyloxyethyl isocyanate to control the ratio of 2-methacryloyloxyethyl groups to be added. A typical structure of the adduct thus produced is shown in Chemical Formula 3. In the chemical formula 3, as described above, since the polyethyleneimine which is the raw material has various branched structures, the structure is not single, and the structure shown in the chemical formula 3 is an example of these. The substance actually obtained is a mixture of compounds having structures as shown in Chemical Formulas N-6 and N-7, and in addition to these examples, it is a mixture of compounds having various branches. The synthesis method will be specifically described later in Synthesis Example 2.

  In Chemical Formula 3, n represents an arbitrary integer between 1 and 1000.

  Another preferred example of the compound having the structural unit represented by Chemical Formula 1 is a case where the compound is a compound obtained by adding 2-methacryloyloxyethyl isocyanate to polyallylamine. The polyallylamine which is a raw material to be used can be one having various molecular weights, branching degrees, and amine ratios as in the case of the polyethyleneimine. By adding 2-methacryloyloxyethyl isocyanate to these, a compound having a repeating unit represented by Chemical Formula 4 can be obtained, which can be used very preferably.

  In Chemical Formula 4, m represents an arbitrary integer between 1 and 1000.

  Another preferred example of the compound having the structural unit represented by Chemical Formula 1 is a case where the compound is a compound obtained by adding 2-methacryloyloxyethyl isocyanate to polydiallylamine. As the polydiallylamine used as a raw material, those having various molecular weights, branching degrees, and amine ratios can be used as in the case of the polyethyleneimine. By adding 2-methacryloyloxyethyl isocyanate to these, a compound having a repeating unit represented by Chemical formula 5 can be obtained, and can be used very preferably.

  In chemical formula 5, p represents an arbitrary integer between 1 and 1000.

  As a feature of the compound shown in the present invention, as a particularly preferable example, for example, a compound in which 2-methacryloyloxyethyl isocyanate is added to polyethyleneimine has a high volume fraction of reactive groups in the entire volume of the molecule. In this case, it exhibits a preferable property that the crosslink density is high, and therefore, it is extremely effective for greatly improving printing durability, which is one of the objects of the present invention. The compounds represented by Chemical formula 3, Chemical formula 4 and Chemical formula 5 contain a large number of polymerizable reactive groups in the molecule, and are particularly preferably used because of their high crosslinking density and large chemical resistance improvement effect. I can do it. Similarly, since a large number of extremely polar urea bonds are contained in the molecule, the use of such a compound in the photopolymerizable composition promotes the permeability of the developer in the non-image area. Even when a low pH developer having a pH of less than 13 is used, a favorable effect that developability is extremely good is recognized. Specific effects will be described later in Examples.

  As the photopolymerization initiator related to the present invention, an organic boron salt is particularly preferably used. The organoboron anion constituting the organoboron salt is represented by the following chemical formula 6.

In the formula, each of R ₃ , R ₄ , R ₅ and R ₆ may be the same or different, and represents an alkyl group, aryl group, aralkyl group, alkenyl group, alkynyl group, cycloalkyl group, or heterocyclic group. To express. Of these, it is particularly preferred that one of R ₃ , R ₄ , R ₅ and R ₆ is an alkyl group and the other substituent is an aryl group.

  In the above-mentioned organoboron anion, a cation that forms a salt is simultaneously present. Examples of the cation in this case include alkali metal ions, onium ions, and cationic sensitizing dyes. Onium salts include ammonium, sulfonium, iodonium and phosphonium compounds. When a salt of an alkali metal ion or onium compound and an organic boron anion is used, photosensitivity in the wavelength range of light absorbed by the dye is imparted by adding a sensitizing dye separately. Further, when an organic boron anion is contained as a counter anion of the cationic sensitizing dye, photosensitivity is imparted according to the absorption wavelength of the sensitizing dye. However, in the latter case, it is preferable to further contain an organic boron anion as a counter anion of the alkali metal or onium salt. Examples of particularly preferred organic boron salts are shown below.

  In the present invention, a trihaloalkyl-substituted compound can be used as a photopolymerization initiator that can be used with an organic boron salt to realize higher sensitivity and higher contrast. Specifically, the trihaloalkyl-substituted compound is a compound having at least one trihaloalkyl group such as a trichloromethyl group or a tribromomethyl group in the molecule. As a preferable example, the trihaloalkyl group is a nitrogen-containing complex. Examples of the compound bonded to the ring group include s-triazine derivatives and oxadiazole derivatives, or trihaloalkylsulfonyl compounds in which the trihaloalkyl group is bonded to an aromatic ring or a nitrogen-containing heterocycle via a sulfonyl group. .

  Particularly preferred examples of trihaloalkyl-substituted nitrogen-containing heterocyclic compounds and trihaloalkylsulfonyl compounds are shown in Chemical Formula 9 and Chemical Formula 10.

  The content of the photopolymerization initiator as described above is preferably in the range of 1% by mass to 50% by mass with respect to the total amount of the photopolymerizable composition.

  One of the most preferred embodiments according to the present invention is a photosensitive composition containing both an organic boron salt and a dye for sensitizing the organic boron salt. In this case, the organic boron salt has photosensitivity in a wavelength region of 700 to 900 nm. Although not shown, the addition of a sensitizing dye shows photosensitivity to light in such a wavelength region for the first time. The photopolymerizable composition according to the present invention has a sensitivity peak at 700 nm to 900 nm, has absorption in this wavelength region, and also contains a sensitizing dye that sensitizes the above-mentioned photopolymerization initiator. Such sensitizing dyes include cyanine, phthalocyanine, merocyanine, coumarin, porphyrin, spiro compound, ferrocene, fluorene, fulgide, imidazole, perylene, phenazine, phenothiazine, polyene, azo compound, diphenylmethane, triphenylmethane, polymethine acridine, coumarin. Ketocoumarin, quinacridone, indigo, styryl, squarylium compound, pyrylium compound, and further described in European Patent No. 0,568,993, US Pat. Nos. 4,508,811, and 5,227,227. Compounds can also be used.

  Although the specific example of the sensitizing dye which can be used preferably is shown below, this invention is not limited to these.

  The present invention preferably contains other polyfunctional monomer in addition to the compound having the structure represented by Chemical Formula 1 in the photopolymerizable composition. Examples of preferred multifunctional monomers include 1,4-butanediol diacrylate, 1,6-hexanediol diacrylate, neopentyl glycol diacrylate, tetraethylene glycol diacrylate, trisacryloyloxyethyl isocyanurate, tripropylene glycol Multifunctional acrylic monomers such as diacrylate, ethylene glycol glycerol triacrylate, glycerol epoxy triacrylate, trimethylol propane triacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, or various weights with acryloyl group or methacryloyl group introduced Polyester (meth) acrylate, urethane (meth) acrylate, epoxy (meth) acrylate Rate, etc. may be used as well.

  As a more preferred example of the polyfunctional monomer, it has a higher sensitivity by containing a compound having two or more styrenic double bond groups in the molecule (hereinafter referred to as a styryl monomer) as shown in the following chemical formula (13). It is preferable because it provides a photopolymerizable composition exhibiting a high tone reproducibility. When a styrenyl monomer is used, a highly sensitive negative photosensitive material can be produced because crosslinking is effectively performed.

In the formula, Z ₁ represents a linking group. R ₈ to R ₁₀ represents a hydrogen atom or a methyl group. R ₇ represents a substitutable group or atom. m ₁ represents an integer of 0 to 4, and k ₁ represents an integer of 2 or more.

Chemical formula 13 will be described in more detail. As the linking group for Z ₂ , an oxygen atom, a sulfur atom, an alkylene group, an alkenylene group, an arylene group, —N (R ₁₁ ) —, —C (O) —O—, —C (R ₁₂ ) ═N—, Examples include —C (O) —, a sulfonyl group, a heterocyclic group, or a group in which two or more are combined. Here, R ₁₁ and R ₁₂ represent a hydrogen atom, an alkyl group, an aryl group, or the like. Furthermore, the above-described linking group may have a substituent such as an alkyl group, an aryl group, or a halogen atom.

  Examples of the heterocyclic group include pyrrole ring, pyrazole ring, imidazole ring, triazole ring, tetrazole ring, isoxazole ring, oxazole ring, oxadiazole ring, isothiazole ring, thiazole ring, thiadiazole ring, thiatriazole ring, indole ring. , Indazole ring, benzimidazole ring, benzotriazole ring, benzoxazole ring, benzthiazole ring, benzselenazole ring, benzothiadiazole ring, pyridine ring, pyridazine ring, pyrimidine ring, pyrazine ring, triazine ring, quinoline ring, quinoxaline ring, etc. A nitrogen-containing heterocyclic ring, a furan ring, a thiophene ring and the like, and a substituent may be bonded to these.

  Among the compounds represented by the above chemical formula 13, preferred compounds exist. Preferred specific examples of the compound represented by Chemical formula 13 are shown below, but the invention is not limited to these examples.

  The addition amount of the above-mentioned styryl monomer is preferably included in the range of 1% by mass to 80% by mass and more preferably in the range of 5% by mass to 50% by mass with respect to the total amount of the photopolymerizable composition. Particularly preferred.

  The photopolymerizable composition according to the present invention may contain a binder component. As the binder, a polymer having a polymerizable double bond group in the side chain can be preferably used. The most preferable binder includes a polymer having a substituent represented by Chemical Formula 17 in the side chain.

In the formula, Z ₂ represents a linking group, R _{14 to} R ₁₆ represent a hydrogen atom or a methyl group, and R ₁₃ represents an arbitrary substitutable atom or group. n represents 0 or 1, m ₂ represents an integer of 0 to 4, and k ₂ represents an integer of 1 to 4.

The chemical formula 17 will be described in more detail. As the linking group for Z ₂ , an oxygen atom, a sulfur atom, an alkylene group, an alkenylene group, an arylene group, —N (R ₁₇ ) —, —C (O) —O—, —C (R ₁₈ ) ═N—, Examples include —C (O) —, a sulfonyl group, a heterocyclic group, and a group represented by the following chemical formula 18 alone or in combination of two or more. Here, R ₁₇ and R ₁₈ represent a hydrogen atom, an alkyl group, an aryl group, or the like. Furthermore, the above-described linking group may have a substituent such as an alkyl group, an aryl group, or a halogen atom. As the linking group in Chemical Formula 17, those containing a heterocyclic ring are preferred, and those in which k ₂ is 1 or 2 are preferred.

  Examples of the heterocyclic group include pyrrole ring, pyrazole ring, imidazole ring, triazole ring, tetrazole ring, isoxazole ring, oxazole ring, oxadiazole ring, isothiazole ring, thiazole ring, thiadiazole ring, thiatriazole ring, indole ring. , Indazole ring, benzimidazole ring, benzotriazole ring, benzoxazole ring, benzthiazole ring, benzselenazole ring, benzothiadiazole ring, pyridine ring, pyridazine ring, pyrimidine ring, pyrazine ring, triazine ring, quinoline ring, quinoxaline ring, etc. A nitrogen-containing heterocyclic ring, a furan ring, a thiophene ring, and the like, and a substituent may be bonded to these heterocyclic rings.

  Preferred examples of the group represented by the formula 17 are shown below, but are not limited to these examples.

  The polymer having a group as shown in the above example preferably has solubility in an alkaline aqueous solution, and therefore, a polymer containing a carboxyl group-containing monomer as a copolymerization component is particularly preferable. In this case, the ratio of the group represented by Chemical Formula 17 in the copolymer composition is preferably 1% by mass or more and 95% by mass or less in the total composition of 100% by mass. If the ratio is less than this, the introduction effect may not be recognized. Further, when it is contained in an amount of 95% by mass or more, the copolymer may not be dissolved in the alkaline aqueous solution. Further, the proportion of the carboxyl group-containing monomer in the copolymer is preferably 5% by mass or more and 99% by mass or less, and the copolymer may not be dissolved in the alkaline aqueous solution at a proportion below this.

  Examples of the carboxyl group-containing monomer include acrylic acid, methacrylic acid, acrylic acid 2-carboxyethyl ester, methacrylic acid 2-carboxyethyl ester, crotonic acid, maleic acid, fumaric acid, maleic acid monoalkyl ester, and fumaric acid monoalkyl. Examples include esters, 4-carboxystyrene and the like.

  In addition to the monomer having a carboxyl group, other monomer components may be introduced into the copolymer to be synthesized and used as a multi-component copolymer. In such cases, monomers that can be incorporated into the copolymer include styrene, 4-methylstyrene, 4-hydroxystyrene, 4-acetoxystyrene, 4-carboxystyrene, 4-aminostyrene, chloromethylstyrene, and 4-methoxystyrene. Styrene derivatives such as methyl methacrylate, ethyl methacrylate, butyl methacrylate, hexyl methacrylate, 2-ethylhexyl methacrylate, cyclohexyl methacrylate, methacrylic acid alkyl esters such as dodecyl methacrylate, phenyl methacrylate, benzyl methacrylate, etc. Methacrylic acid aryl ester or alkyl aryl ester, 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, methoxydiethylene glycol monomethacrylate Asteryl, methacrylic acid methoxypolyethylene glycol monoester, methacrylic acid ester having alkyleneoxy group such as methacrylic acid polypropylene glycol monoester, amino group-containing methacrylic acid ester such as 2-dimethylaminoethyl methacrylate and 2-diethylaminoethyl methacrylate Or the same examples as the corresponding methacrylic acid esters as acrylic esters, or vinylphosphonic acid as a monomer having a phosphoric acid group, amino group-containing monomers such as allylamine and diallylamine, or vinylsulfonic acid And salts thereof, allylsulfonic acid and salts thereof, methallylsulfonic acid and salts thereof, styrenesulfonic acid and salts thereof, 2-acrylamido-2-methylpropanesulfonic acid and Monomers having a sulfonic acid group such as a salt of, monomers having a nitrogen-containing heterocycle such as 4-vinylpyridine, 2-vinylpyridine, N-vinylimidazole, N-vinylcarbazole, or monomers having a quaternary ammonium base 4-vinylbenzyltrimethylammonium chloride, acryloyloxyethyltrimethylammonium chloride, methacryloyloxyethyltrimethylammonium chloride, quaternized product of dimethylaminopropylacrylamide with methyl chloride, quaternized product of N-vinylimidazole with methyl chloride, 4-vinyl Benzylpyridinium chloride, etc., or acrylonitrile, methacrylonitrile, acrylamide, methacrylamide, dimethylacrylamide, diethylamine Acrylamide or methacrylamide derivatives such as chloramide, N-isopropylacrylamide, diacetone acrylamide, N-methylol acrylamide, N-methoxyethyl acrylamide, 4-hydroxyphenyl acrylamide, acrylonitrile, methacrylonitrile, phenylmaleimide, hydroxyphenylmaleimide, Vinyl acetates such as vinyl acetate, vinyl chloroacetate, vinyl propionate, vinyl butyrate, vinyl stearate, vinyl benzoate, vinyl ethers such as methyl vinyl ether, butyl vinyl ether, others, N-vinyl pyrrolidone, acryloyl morpholine, tetrahydrofluor Furyl methacrylate, vinyl chloride, vinylidene chloride, allyl alcohol, vinyl trimethoxysilane It may be used glycidyl methacrylate and various monomers as arbitrary copolymerization monomers. The proportion of these monomers in the copolymer may be any as long as the preferred proportion of the group and carboxyl group-containing monomer represented by Chemical Formula 17 in the copolymer composition described above is maintained. It can be introduced at a rate.

  There is a preferable range for the molecular weight of the polymer as described above, and the weight average molecular weight is preferably in the range of 1,000 to 1,000,000, and more preferably in the range of 10,000 to 300,000.

  Examples of polymers having a group represented by Chemical Formula 17 in the side chain according to the present invention are shown below. In the formula, the number represents the mass% of each repeating unit in the copolymer total composition of 100 mass%.

  When utilizing conventional radical photopolymerization, it is necessary to provide a resin such as polyvinyl alcohol which is easily affected by oxygen in the atmosphere and generally has an oxygen barrier property as an overlayer on the surface of the photosensitive layer. . Further, in order to promote or complete the polymerization after exposure, it was necessary to perform a heat treatment at a temperature of about 100 ° C. for about several minutes. On the other hand, when the polymer and the styrenyl monomer are used in combination, a sufficiently photocuring system is provided without providing an overlayer as described above, and a heat treatment is performed after the exposure. The feature is that it is not necessary.

  An important point as one of the effects of the present invention is that, since the developability is good, it is difficult to cause fogging and gives a high-contrast image reproduction as a photosensitive characteristic, and is particularly preferably used as a photosensitive composition for laser scanning exposure. It is a point that can be done. In particular, when a near-infrared semiconductor laser emitting near 830 nm is used as the light source, the edge portion of the image is reproduced sharply and gives high-resolution image quality, so that it can be used very preferably.

  In addition, as an element constituting the photopolymerizable composition, various kinds of dyes and pigments are added for the purpose of enhancing the visibility of the image, and inorganic fine particles or organic fine particles are used for the purpose of preventing blocking of the photosensitive composition. It is also preferably carried out.

  In the photopolymerizable composition, it is preferable to add a polymerization inhibitor in order to prevent a curing reaction in the dark due to thermal polymerization for further long-term storage. As the polymerization inhibitor preferably used for such purposes, various known phenol compounds can be used.

  Regarding the thickness of the photosensitive layer itself when used as a lithographic printing plate material, it is preferably formed on the support with a dry thickness in the range of 0.5 μm to 10 μm, and more preferably in the range of 1 μm to 5 μm. It is extremely preferable for greatly improving the performance. The photosensitive layer is prepared by mixing a solution containing the above three elements, and is applied onto a support and dried using various known coating methods. As the support, for example, a film or polyethylene-coated paper may be used, but a more preferable support is an aluminum plate that is polished and has an anodized film.

  In order to use a material having a photosensitive layer formed on a support as described above as a printing plate, an alkaline developer is obtained by subjecting the exposed part to exposure or laser scanning exposure and crosslinking the exposed part. Therefore, pattern formation is performed by eluting unexposed portions with an alkaline developer described later.

  The alkaline developer is not particularly limited as long as it is a solution that dissolves the polymer of the present invention, but preferably sodium hydroxide, potassium hydroxide, sodium silicate, potassium silicate, sodium metasilicate, potassium metasilicate, An aqueous developer containing an alkaline compound such as monoethanolamine, diethanolamine, triethanolamine, triethylammonium hydroxide, etc., can selectively dissolve the unexposed areas and expose the lower support surface. preferable. Furthermore, it is also preferable to add various alcohols such as ethanol, propanol, isopropanol, ethylene glycol, diethylene glycol, triethylene glycol, glycerin and benzyl alcohol to the alkaline developer. The pH of the developer is particularly preferably less than 13. Moreover, after performing development processing using such an alkaline developer, normal gumming is preferably performed using gum arabic or the like.

  Hereinafter, the present invention will be described in more detail by way of examples. However, the present invention is not limited to these examples. As the polymer and styryl monomer described in the examples, those obtained by the method described in JP-A No. 2001-290271 were used. In addition, the number of parts and percentage in an Example are based on mass.

Synthesis Example 1 (Synthesis Example of M-1 in Chemical Formula 2)
Dissolve 30 g of ethylenediamine in 200 g of dichloromethane and take 155 g of Karenz MOI obtained from Nippon Shokubai Co., Ltd. as 2-methacryloyloxyethyl isocyanate from the dropping funnel so that the internal temperature does not exceed 10 ° C. in an ice water bath. Dropping was performed. After completion of the dropwise addition, the mixture was further stirred at room temperature for 10 hours, the whole was transferred to a separatory funnel, and the organic phase was washed three times with pure water, and then the organic phase was evaporated to obtain an oily substance. As a result of structural analysis by proton NMR, it was confirmed that the compound had the target structure of M-1 in Chemical Formula 2.

Synthesis Example 2 (Synthesis Example of Chemical Formula 3)
Epomin SP-006 (molecular weight 600, amine ratio: first grade: second grade: third grade = 35: 35: 30) obtained from Nippon Shokubai Co., Ltd. was used as polyethyleneimine. Karenz MOI obtained from Nippon Shokubai Co., Ltd. was used as 2-methacryloyloxyethyl isocyanate. In a 1 liter flask equipped with a stirrer and a thermometer, 75 g of Epomin SP-006 was added, and 450 g of diethylene glycol dimethyl ether was added to obtain a uniform solution. The inside temperature was kept at 10 ° C. on an ice water bath, 205.5 grams of Karenz was gradually added dropwise, and the dropping rate was adjusted so that the inside temperature did not exceed 20 ° C. After completion of the dropwise addition, the mixture was further stirred at room temperature for 12 hours, and after removing the solvent by distillation under reduced pressure, the resulting viscous oil-like substance was dried overnight in a vacuum dryer. As a result of analyzing the structure by proton NMR, it was confirmed to be a mixture of compounds represented by Chemical Formula 3.

Synthesis Example 3 (Synthesis Example of Chemical Formula 4)
Synthesis was performed in exactly the same manner as in Synthesis Example 1 except that PAA-01 (molecular weight 1000) obtained from Nitto Boseki Co., Ltd. was used as polyallylamine. As a result of analyzing the structure by proton NMR, the compound was identified as shown in Chemical Formula 4.

Synthesis Example 4 (Synthesis Example of Chemical Compound 5)
The synthesis was performed in the same manner as in Synthesis Example 1 except that PAS-M-1 (molecular weight 20000) obtained from Nitto Boseki Co., Ltd. was used as the polydiallylamine-sulfone copolymer. As a result of analyzing the structure by proton NMR, it was identified as a compound represented by the following chemical formula (28).

Using an anodized aluminum plate that has been grained with a thickness of 0.24 mm, a photosensitive coating solution represented by the following prescription is applied thereon so that the dry thickness is 2.5 μm, Drying was carried out in an oven at 80 ° C. for 5 minutes to prepare a photosensitive lithographic printing plate material.
<Photosensitive coating solution>
Binder polymer (P-1 in chemical formula 23) 10 parts Photopolymerization initiator (BC-6 in chemical formula 8) 0.9 part Photopolymerization initiator (T-4 in chemical formula 9) 0.5 part
10% phthalocyanine dispersion (colorant) 0.5 part Compound of the present invention (Table 1 below)
C-5 3 parts Trimethylolpropane triacrylate 3 parts Sensitizing dye (S-33 in Chemical formula 11) 0.2 parts Methylenebis (2,6-di-t-butylphenol) 0.1 part Dioxane 70 parts Cyclohexanone 20 copies

  Various photosensitive lithographic printing plate materials were prepared using the compounds according to the present invention in the photosensitive coating solution as shown in Table 1. At the same time, a sample of Comparative Example 1 was also prepared in exactly the same manner as the above photosensitive coating solution formulation except that the compound of the present invention was not used. As Comparative Example 2, a sample was prepared using the same amount of diethylene glycol dimethacrylate as the compound of the present invention as a compound similar to the compound of the present invention.

The obtained light-sensitive material was exposed using a trend setter (drawing apparatus equipped with a 830 nm laser) manufactured by Creo in accordance with the exposure amount irradiated to the plate surface of 80 mJ / cm ² . The exposed photosensitive lithographic printing plate material was developed under various conditions using a developer prepared with the following constitution.

(Developer formulation)
Dimethylaminoethanol 30 parts Tetramethylammonium hydroxide 5 parts Sodium butylnaphthalenesulfonate 5 parts The total amount was adjusted to 1000 parts by adding water, and phosphoric acid was added to adjust the pH of the developer to 10.8.

(Developability test)
Using the sample exposed as described above, a developability test was performed as follows. Development was performed using an automatic developing device P-1310T manufactured by Mitsubishi Paper Industries. The development temperature is set to two conditions of 28 ° C. and 30 ° C., and the processing time is processed under three conditions of 10 seconds, 12 seconds, and 15 seconds at each temperature. The case where it disappeared was evaluated as ◯, the case where a slight residual film was observed was evaluated as Δ, and the case where a residual film was clearly generated and the dissolution was poor was evaluated as X). The results are summarized in Table 2.

(Printability test)
Of the samples of the examples obtained in the above developability test, normal offset printing was performed using a sample obtained under development processing conditions of 28 ° C. and 15 seconds. A printing test was simultaneously performed using a sample obtained by the same treatment at 28 ° C. for 15 seconds as a comparative sample. The printing press uses Mitsubishi Heavy Industries Co., Ltd. web offset press lithopier, the printing ink uses Tokyo Ink Co., Ltd. newspaper off-wheel red ink, and the hygroscopic liquid is Toyo Ink Co., Ltd.'s hygroscopic liquid for offset printing. A 1% aqueous solution of Unity WKK was used. As printing evaluation items, the printing durability was evaluated by measuring the reflection density of the solid portion in the test image on the printing plate and tracing the decrease in the reflection density from the beginning of printing. When the reflection density of the solid portion on the printing plate reached about 0.6, it was confirmed separately that the ink deposition property deteriorated and the ink was not partially applied. The results are summarized in Table 3. When using a photosensitive lithographic printing plate of Reference Example 1 and Examples 2-4, good prints can be obtained even in the printing of 150,000 impressions with respect to printing durability, film thinning of the image portion on the printing plate Was also minor. In addition, good results were obtained without the occurrence of soiling. In Comparative Examples 1 and 2, scumming occurred from the start of printing to about 5000 impressions, but slight scumming was observed in the printed materials thereafter. Further, about half of the image film was rubbed after printing 150,000 impressions.

(Chemical resistance evaluation)
The lithographic printing plate precursors of Reference Example 1, Examples 2 to 4 and Comparative Examples 1 and 2 were exposed / developed and printed in the same manner as in the evaluation of printing durability. At this time, each time 10,000 sheets were printed, a process of wiping part of the image area of the printing plate with a cleaner (manufactured by Fuji Photo Film Co., Ltd., Multi-Cleaner CL-2) was added to evaluate chemical resistance. The chemical resistance was evaluated by measuring the reflection density of the image area after printing of the area where the cleaner solution was applied. The results are shown in Table 4 below.

(Ink fillability evaluation)
In the evaluation of chemical resistance, after the plate surface cleaning operation at the time when 10,000 sheets were printed, further wiping was performed, and printing was resumed. From the restart of printing, ink was supplied to the image area, and ink inking property was evaluated by the number of printed sheets until a stable printed matter was obtained. The results are shown in Table 5 below.

  According to the present invention, a highly sensitive photosensitive composition that does not require an overlayer and is hardly affected by oxygen can be obtained. The present invention relates to a photosensitive composition and a photosensitive lithographic printing plate material capable of forming an image using a scanning exposure apparatus using a light source such as a near infrared laser emitting near 830 nm. Furthermore, it is related with the photosensitive composition suitable for formation of the resist for printed wiring board preparation, a color filter, a fluorescent substance pattern, etc.

Claims (3)

It has a structural unit represented within the formula 1 molecule, and polyethyleneimine, which contains a polyallylamine, and any of the compounds selected from Polydiallylamine 2- methacryloyloxy compounds obtained by adding acryloyloxyethyl isocyanate A photopolymerizable composition characterized by the above.

R ₁ and R ₂ each represent a hydrogen atom or an arbitrary group. A represents an alkylene group having 1 to 4 carbon atoms.   The photopolymerizable composition according to claim 1, wherein the photopolymerizable composition contains a polymer having a styrenic double bond in a side chain.   A photosensitive lithographic printing plate material using the photopolymerizable composition according to claim 1 or 2.