JP2007269891A - Photopolymerizable monomer, photosensitive composition and lithographic printing plate by utilizing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a photopolymerizable monomer having a high photopolymerizable property, also a photosensitive composition having a sufficient strength on image-forming, having a good dissolution property on developing and without causing deterioration such as poor dissolution even on preserving for a long period, especially a negative type photosensitive composition having a sufficient sensitivity in scanning exposure by a laser from visible light to infrared light and excellent in strength at an image part, and a lithographic printing plate by utilizing the same. <P>SOLUTION: This photosensitive monomer is obtained by selecting from a photosensitive monomer having ≥2 unit structures expressed by general formula 1 in its molecule, a photosensitive monomer having ≥2 unit structures expressed by general formula 3 in its molecule, a photosensitive monomer expressed by general formula 5 and a photosensitive monomer expressed by general formula 7, and has 5 to 45% SH-remaining rate of the photosensitive monomer. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a negative photosensitive composition. Applications include photosensitive resins, printing plates, inks, paints, adhesives, crosslinking agents, optical lens materials, optical fiber coatings, three-dimensional modeling, holographic recording materials, printed wiring boards, and photosensitive materials that can be used for electronic materials such as ICs. The present invention relates to a sex composition. Furthermore, it is related with the said photosensitive composition in which image formation by scanning exposure, such as a laser, is possible. Furthermore, it is related with the lithographic printing plate using the said photosensitive composition.

  Photocrosslinking systems that are sensitive to radiation and undergo a crosslinking reaction in the irradiated area are roughly classified into photoradical systems and photocationic systems based on their mechanisms. As the photoradical system, a system mainly composed of a combination of acrylates and a photoradical generator is mainly used, and one of the characteristics is that the room temperature curability is good and the curing speed is fast. Even if light irradiation is performed, the polymerization reaction rate does not reach 100%, due to the adverse effect on the physical properties of the cured product due to the remaining acrylate monomer, bleeding of the acrylate monomer from the cured product, and hydrolysis of the cured product under strong alkali conditions It has various problems such as deterioration.

  On the other hand, in the photocation system, an onium salt photocation generator such as an iodonium salt or a sulfonium salt is used, and a cationic ring-opening polymerization of an epoxy compound or a cationic polymerization of vinyl ethers is used. A similar photocrosslinking system is constructed by this method. In this case, the greatest advantage is that the polymerization is not inhibited by oxygen, and it is used for the curing reaction in air. Disadvantages are that the curing rate is often low, heat treatment (post-cure) is necessary after irradiation to promote the cross-linking reaction, and polymerization inhibition is present in the presence of basic substances. was there.

  Furthermore, with the remarkable progress of semiconductor lasers, it has become possible to easily use near-infrared laser light sources of 700 to 1300 nm, and photosensitive materials and photosensitive lithographic printing plates corresponding to the laser beams have attracted attention. .

  As a photopolymerizable composition having photosensitivity to visible light to near infrared light, JP-A-9-134007 discloses a radically polymerizable compound having an ethylenically unsaturated bond and an absorption peak at 400 to 500 nm. A lithographic printing plate material containing a photosensitizing dye and a polymerization initiator is disclosed. JP-A-62-143044, JP-A-62-1050242, JP-A-5-5988, JP-A-5-194619, JP-A-5-197069, JP-A-2000-98603, etc. disclose combinations of organic boron anions and dyes, and JP-A-4-31863 and JP-A-6-43633 disclose dyes and s- Combinations with triazine-based compounds are disclosed, and JP-A-7-20629 and JP-A-7-271029 disclose a resole resin, a novolac resin, an infrared absorber and the like. Discloses a combination of photoacid generator, JP-11-212252, a combination of a specific polymer and a photoacid generator and a near infrared sensitizing dyes is disclosed in JP-A-11-231535.

  Further, a polymerizable monomer having two or more vinylphenyl groups and a photosensitive composition using the same are known. For example, JP-A-2-53783 (Patent Document 1) and JP-A-2001-290271 are known. (Patent Document 2) and JP-A-2003-26744 (Patent Document 3).

  Further, as a polymerizable monomer, nitrogen-containing unsaturated monomers such as N-vinyl pyrrolidone, N-vinyl carbazole, N-vinyl acetamide, vinyl pyridine and the like can be used in the photocurable composition as disclosed in JP-A-11-106413 ( Patent Document 4). JP-A-8-297364 (Patent Document 5) describes that N-vinylpyrrolidone is used as a photopolymerizable compound having an ethylenically unsaturated group. Furthermore, a photopolymerization initiator and a photosensitive composition containing a specific boron compound and a polyfunctional branched thiol are described in JP-A-2003-25918 (Patent Document 6).

In the above-described photosensitive composition, a portion irradiated with light is cured, and an unexposed portion (non-cured portion) is dissolved and removed by a development process to form a relief image. However, the image is insufficient because photopolymerization is insufficient. The strength of the part was not sufficient. In particular, when used as a lithographic printing plate, insufficient photopolymerization affects printing durability. Furthermore, in the case of a photopolymerizable monomer that undergoes sufficient photopolymerization, if the photosensitive composition is stored for a long period of time, the photosensitive composition to which a monomer with high photopolymerization is added has poor elution properties, and further irradiated with light. However, there was a problem that no curing reaction occurred.
Japanese Patent Laid-Open No. 2-53783 JP 2001-290271 A JP 2003-26744 A JP-A-11-106413 JP-A-8-297364 JP 2003-25918 A

  It is an object of the present invention to find a photopolymerizable monomer having high photopolymerizability, and has sufficient strength at the time of image formation and good dissolution during development, and deterioration such as poor dissolution even when stored for a long period of time. It is an object to find a photosensitive composition in which no occurrence occurs. In particular, it is an object to provide a negative photosensitive composition having sufficient sensitivity and excellent image portion strength even in scanning exposure by visible to infrared laser, and a lithographic printing plate using the same. To do.

As a result of intensive studies to solve the above problems, the present inventor has found that the above problems can be basically solved by using the photosensitive composition described below.
1) Photopolymerizable monomer having two or more unit structures represented by the following general formula 1 in the molecule; Photopolymerizable monomer having two or more unit structures represented by the following general formula 3 in the molecule; A polymerizable monomer selected from the photopolymerizable monomer represented by 5 and the photopolymerizable monomer represented by the general formula 7, wherein the residual ratio of -SH of the photopolymerizable monomer is 5 to 45%. A photopolymerizable monomer characterized by

In General Formula 1, L ¹ represents a divalent linking group, and A represents a hydrogen atom or a structure of the following General Formula 2.

In General Formula 2, L ² represents a divalent linking group, and VP represents a phenyl group substituted with a vinyl group.

In General Formula 3, A ₁₀ represents a hydrogen atom or a structure of the following General Formula 4.

In General Formula 4, L ¹¹ represents a divalent linking group consisting of an atom or a group of atoms selected from a hydrogen atom, a carbon atom, a nitrogen atom, an oxygen atom, and a sulfur atom, and VP represents a phenyl group substituted with a vinyl group. . n ₁ represents 0 or 1.

In the general formula 5, L ²¹ represents a polyvalent linking group consisting of an atom or a group of atoms selected from a hydrogen atom, a carbon atom, a nitrogen atom, an oxygen atom, and a sulfur atom. A ₂₀ and A ₂₁ each represent a hydrogen atom or a structure of the following general formula 6, and may be the same or different.

In General Formula 6, L ²² represents a polyvalent linking group composed of an atom or a group of atoms selected from a hydrogen atom, a carbon atom, a nitrogen atom, an oxygen atom, and a sulfur atom. Y ²¹ may be the same or different and represents a phenylene group or —CO— group which may have a substituent. n ₂₁ represents 0 or 1. R ^21, R ^22, R ²³ may be the the same or different and each a hydrogen atom, a halogen atom, a carboxyl group, a sulfo group, a nitro group, a cyano group, an amide group, an amino group, an alkyl group, an aryl group Represents a group selected from an alkoxy group, an aryloxy group, an alkylthio group, an arylthio group, an alkylamino group, an arylamino group, an acyl group, an alkoxycarbonyl group, an aryloxycarbonyl group, an alkylsulfonyl group, and an arylsulfonyl group.

In general formula 7, A ₃₀ and A ₃₁ each represent a hydrogen atom or the structure of general formula 8 below, and R ³⁴ and R ^{35 which} may be the same or different may be the same or different, A hydrogen atom, an alkyl group, an alkenyl group, an aryl group and a heterocyclic group are represented. Further, R ³⁴ and R ³⁵ may be combined to form a ring structure. A ₃₀ and A ₃₁ each represent a hydrogen atom or a structure of the following general formula 8, and may be the same or different.

In the general formula 8, R ³¹ , R ³² , and R ³³ are synonymous with R ²¹ , R ^22, and R ²³ , respectively. L ³¹ has the same meaning as L ²² in formula 3. Y ³¹ is synonymous with Y ²¹ . n ₃₁ represents 0 or 1, respectively.
2) A photosensitive composition comprising the photopolymerizable monomer of 1) above.
3) The photosensitive composition as described in 2) above, further containing a photopolymerization initiator.
4) The photosensitivity as described in 2) or 3) above, which contains the photopolymerizable monomer of 1), a photopolymerization initiator, and a sensitizing dye that sensitizes in the wavelength range of 380 to 1100 nm. Composition.
5) A lithographic printing plate characterized in that the photosensitive composition according to any one of 2) to 4) above is used for a photosensitive layer provided on a support.

  According to the present invention, a photopolymerizable monomer having high photopolymerizability, sufficient strength at the time of image formation, good elution during development, and no deterioration such as poor elution even when stored for a long period of time is provided. I can do it. In particular, it is possible to provide a negative photosensitive composition excellent in image portion strength with sufficient sensitivity even in scanning exposure using visible to infrared laser, and a lithographic printing plate using the same.

  First, the photopolymerizable monomer of the general formula 1 will be described in detail. The phenyl group substituted by the vinyl group represented by VP, which is included in the structure A of the general formula 1, is specifically represented by the following general formula 9.

In the formula of the general formula 9, R ¹ , R ² and R ³ may be the same or different and are each a hydrogen atom, a halogen atom, a carboxyl group, a sulfo group, a nitro group, a cyano group, an amide group, From amino group, alkyl group, aryl group, alkoxy group, aryloxy group, alkylthio group, arylthio group, alkylamino group, arylamino group, acyl group, alkoxycarbonyl group, aryloxycarbonyl group, alkylsulfonyl group, arylsulfonyl group The alkyl group and aryl group constituting these groups are a halogen atom, carboxyl group, sulfo group, nitro group, cyano group, amide group, amino group, alkyl group, aryl group, alkenyl group, alkynyl. Group, hydroxy group, alkoxy group, aryloxy group, alkylthio group, aryl It may be substituted with a ruthio group, an alkylamino group, an arylamino group, an acyl group, an alkoxycarbonyl group, an aryloxycarbonyl group, an alkylsulfonyl group, an arylsulfonyl group or the like. Among these groups, those in which R ¹ and R ² are hydrogen atoms and R ³ is a hydrogen atom or a lower alkyl group having 4 or less carbon atoms (for example, a methyl group, an ethyl group, etc.) are particularly preferable.

  Furthermore, the benzene ring of general formula 9 may have other substituents. Examples include halogen atoms, carboxyl groups, sulfo groups, nitro groups, cyano groups, amide groups, amino groups, alkyl groups, aryl groups, alkenyl groups, alkynyl groups, hydroxy groups, alkoxy groups, aryloxy groups, alkylthio groups. , An arylthio group, an alkylamino group, an arylamino group, an acyl group, an alkoxycarbonyl group, an aryloxycarbonyl group, an alkylsulfonyl group, an arylsulfonyl group, and the like, and an alkyl group and an aryl constituting these groups Groups are halogen atoms, carboxyl groups, sulfo groups, nitro groups, cyano groups, amide groups, amino groups, alkyl groups, aryl groups, alkenyl groups, alkynyl groups, hydroxy groups, alkoxy groups, aryloxy groups, alkylthio groups, arylthio groups. Group, alkylami Group, an arylamino group, an acyl group, an alkoxycarbonyl group, an aryloxycarbonyl group, an alkylsulfonyl group, may be substituted by an arylsulfonyl group.

In the general formulas 1 and 2, the divalent linking group represented by L ¹ and L ² is specifically an atom selected from a carbon atom, a nitrogen atom, an oxygen atom, a sulfur atom, etc. In addition, a hydrocarbon group linking group such as alkylene or arylene is preferable. In particular, an alkylene group having a total carbon number of L ¹ and L ² of 6 or less is preferable. These groups may have further substituents if possible.

When L ¹ and L ² described above have a substituent, examples thereof include halogen atoms, carboxyl groups, sulfo groups, nitro groups, cyano groups, amide groups, amino groups, alkyl groups, aryl groups, alkenyl groups, alkynyls. Group, hydroxy group, alkoxy group, aryloxy group, alkylthio group, arylthio group, alkylamino group, arylamino group, acyl group, alkoxycarbonyl group, aryloxycarbonyl group, alkylsulfonyl group, arylsulfonyl group and the like.

  The photopolymerizable monomer of the present invention preferably has two or more unit structures represented by the general formula 1 as described above in a single molecule, and among them, 3 to 3 in a single molecule. What has six is especially preferable.

Next, the photopolymerizable monomer represented by the general formula 3 will be described in detail. In general formula 3, A ₁₀ is represented by the following general formula 4.

In the general formula 4, the divalent linking group consisting of an atom or a group of atoms selected from a hydrogen atom, a carbon atom, a nitrogen atom, an oxygen atom and a sulfur atom represented by L ¹¹ is specifically shown below. And a group composed of the structural unit exemplified in 11 and the heterocyclic ring shown below. These groups may be used alone or in any combination of two or more. Furthermore, these groups may have a substituent. N _{1 in} A ₁₀ represents 0 or 1.

Examples of the heterocyclic ring constituting L ¹¹ include pyrrole ring, pyrazole ring, imidazole ring, triazole ring, tetrazole ring, isoxazole ring, oxazole ring, oxadiazole ring, isothiazole ring, thiazole ring, thiadiazole ring, thia Triazole 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 And a nitrogen-containing ring such as a ring and a quinoxaline ring, a furan ring, a thiophene ring, and the like. These heterocyclic rings may have a substituent.

  When the polyvalent linking group described above has a substituent, examples of the substituent include a halogen atom, a carboxyl group, a sulfo group, a nitro group, a cyano group, an amide group, an amino group, an alkyl group, an aryl group, an alkenyl group, and an alkynyl group. Group, hydroxy group, alkoxy group, aryloxy group, alkylthio group, arylthio group, alkylamino group, arylamino group, acyl group, alkoxycarbonyl group, aryloxycarbonyl group, alkylsulfonyl group, arylsulfonyl group and the like.

  Next, the photopolymerizable monomer represented by the general formula 5 will be described in detail.

In general formula 5, L ²¹ has the same meaning as L ¹¹ described above. A ₂₀ and A ₂₁ may be the same or different and are represented by the following general formula 6.

In the formula, R ²¹ , R ²² and R ²³ may be the same or different and are each a hydrogen atom, a halogen atom, a carboxyl group, a sulfo group, a nitro group, a cyano group, an amide group, an amino group, or an alkyl group. Represents a group selected from aryl group, alkoxy group, aryloxy group, alkylthio group, arylthio group, alkylamino group, arylamino group, acyl group, alkoxycarbonyl group, aryloxycarbonyl group, alkylsulfonyl group, arylsulfonyl group The alkyl group and aryl group constituting these groups are a halogen atom, carboxyl group, sulfo group, nitro group, cyano group, amide group, amino group, alkyl group, aryl group, alkenyl group, alkynyl group, hydroxy group, An alkoxy group, an aryloxy group, an alkylthio group, an arylthio group, Alkylamino group, arylamino group, acyl group, alkoxycarbonyl group, aryloxycarbonyl group, alkylsulfonyl group, arylsulfonyl group and the like may be substituted. Among these groups, those in which R ²¹ is a hydrogen atom or a lower alkyl group having 4 or less carbon atoms (for example, a methyl group, an ethyl group, etc.) and R ²² and R ²³ are hydrogen atoms are particularly preferable.

In the formula, L ²² may be the same or different, and has the same meaning as L ¹¹ and L ²¹ , respectively.

In the formula, Y ²¹ represents a phenylene group (specifically, 1,2-phenylene group, 1,3-phenylene group, 1,4-phenylene group) or —CO— group. The above-mentioned phenylene group may have a substituent, and as such a substituent, a halogen atom, a carboxyl group, a sulfo group, a nitro group, a cyano group, an amide group, an amino group, an alkyl group, an aryl group, Photosensitive, such as alkenyl group, hydroxy group, alkoxy group, aryloxy group, alkylthio group, alkylamino group, arylamino group, acyl group, alkoxycarbonyl group, aryloxycarbonyl group, alkylsulfonyl group, arylsulfonyl group, etc. When the composition is used as a lithographic printing plate material, it is preferable that Y ²¹ is a phenylene group. In the formula, n ₂₁ represents 0 or 1.

  Next, the photopolymerizable monomer represented by the general formula 7 will be described in detail.

R ³⁴ and R ³⁵ may be the same or different and each represents a hydrogen atom, an alkyl group, an alkenyl group, an aryl group or a heterocyclic group. Among these groups, alkyl groups having 10 or less carbon atoms and aryl groups are preferable. These groups are halogen atoms, carboxyl groups, sulfo groups, nitro groups, cyano groups, amide groups, amino groups, alkyl groups, aryl groups, alkenyl groups, alkynyl groups, hydroxy groups, alkoxy groups, aryloxy groups, alkylthio groups. , Arylthio group, alkylamino group, arylamino group, acyl group, alkoxycarbonyl group, aryloxycarbonyl group, alkylsulfonyl group, arylsulfonyl group and the like. R ³⁷ and R ³⁸ may be combined to form a ring structure. Specific examples of such a ring structure include pyrrolidine ring, piperidine ring, 1,2,3,6-tetrahydropyridine ring, hexamethyleneimine. Ring, heptamethyleneimine ring, imidazole ring, piperazine ring, 1,4,5,6, -tetrahydropyrimidine ring, morpholine ring, thiazolylidine ring, thiomorpholine ring, pyrrole ring, pyrazole ring, triazole ring, tetrazole ring, etc. Can be mentioned. These ring structures may have a substituent as described above.

A ₃₀ and A ₃₁ may be the same or different and are represented by the following general formula 8.

In the formula, R ³¹ , R ³² and R ³³ have the same meanings as R ²¹ , R ²² and R ²³ in formula 5, respectively. Among these groups, those in which R ³¹ is a hydrogen atom or a lower alkyl group having 4 or less carbon atoms (for example, a methyl group, an ethyl group, etc.) and R ³² and R ³³ are hydrogen atoms are particularly preferable.

L ³¹ has the same meaning as L ²² in formula 5. Y ³¹ has the same meaning as Y ²¹ in the general formula 5, in particular when used as a lithographic printing plate material applications are those Y ³¹ is a phenylene group is preferred. Each of n ³¹ has the same meaning as n ²¹ in formula 5.

The photopolymerizable monomer of the present invention will be described in detail in the Examples, but the structures A, A ₁₀ , A ₂₀ , A _{21 in} the general formulas in the general formulas 1, 3, 5, 7 are shown. , a _30, a _31, but by combining the intermediate having a structure of a hydrogen atom, then the general formula 2 to a part of the hydrogen atoms in the general formula 4, formula 6, the intermediate having a structure of general formula 8 It can be obtained by substitution. Actually, the intermediates in the general formulas 1, 3, 5, and 7 in the general formulas A, A ₁₀ , A ₂₀ , A ₂₁ , A ₃₀ , A ₃₁ are hydrogen atoms. Intermediates having the structures of the general formula 2, the general formula 4, the general formula 6, and the general formula 8 having a mole number of 95 to 55% with respect to the mole number of hydrogen atoms bonded to the mercapto group, It can be obtained by reacting an intermediate having the structure of General Formula 2, General Formula 4, General Formula 6, and General Formula 8. In the photopolymerizable monomer of the present invention, the structures A, A ₁₀ , A ₂₀ , A ₂₁ , A ₃₀ , A ₃₁ in the general formulas in the general formulas 1, 3, 5, 7 are hydrogen atoms. A certain ratio (residual ratio) is preferably 5 to 45%, and more preferably 10 to 30%. As understood from the synthesis method of the compound of the present invention, since it is difficult to cause a substitution reaction only at a specific position, it is difficult to specify the structure of the resulting product. In the photopolymerizable monomer of the present invention, the residual ratio of hydrogen atoms is R% = (I _SH / (, where ¹ H-NMR styrene vinyl proton signal intensity is I _SB and SH proton signal intensity is I _SH. I _SB + I _SH )) × 100. When the residual ratio of SH is higher than the above ratio, the elution property under high temperature and high humidity is lowered, and when the residual ratio is further increased, the image strength is lowered. On the other hand, when the SH residual ratio is lower than 5%, the crosslinking efficiency is lowered, and as a result, the image intensity obtained by photopolymerization is lowered.

  Since the photopolymerizable monomer of the present invention cannot specify the remaining position of the hydrogen atom in this way, a specific example of the structure when the remaining ratio of the hydrogen atom is 0% is shown below. It is not limited to these examples.

  Specific examples of the photopolymerizable monomer of the general formula 1 of the present invention are as follows.

  Specific examples of the photopolymerizable monomer of the general formula 3 of the present invention are as follows.

  Specific examples of the photopolymerizable monomer of the general formula 5 of the present invention are as follows.

  Specific examples of the photopolymerizable monomer of the general formula 7 of the present invention are as follows.

  As a manufacturing method of the photopolymerizable monomer of this invention, it can synthesize | combine using a conventionally well-known chemical reaction.

  When the photopolymerizable monomer of the present invention is used for an optical material such as an optical lens, the photopolymerizable monomer of the present invention is preferably contained in a proportion of 20 to 80% by mass in the total photopolymerizable monomer composition. When the content is 30 to 70% by mass, a resin excellent in hardness, weather resistance and the like is obtained, which is particularly preferable. The photopolymerization method for obtaining an optical material resin using the photopolymerizable monomer of the present invention is not particularly limited, and a conventionally known method described in JP-A-2-268170 can be employed.

  The sensitizing dye according to the present invention sensitizes the decomposition of the photopolymerization initiator in a wavelength range of 380 to 1300 nm, and includes various cationic dyes, anionic dyes and neutral dyes having no charge. Merocyanine, coumarin, xanthene, thioxanthene, azo dyes and the like can be used. Among these, particularly preferable examples are dyes selected from cyanine, carbocyanine, hemicyanine, methine, polymethine, triarylmethane, indoline, azine, thiazine, xanthene, oxazine, acridine, rhodamine, and azamethine dyes as cationic dyes. is there. Furthermore, as a sensitizing dye corresponding to a violet semiconductor laser having an oscillation wavelength in the range of 380 nm to 410 nm, a system containing a pyrylium compound or a thiopyrylium compound is preferable. Examples of preferred sensitizing dyes according to the present invention are shown below.

  Among the above sensitizing dyes, in particular, in a system in which light in the near-infrared to infrared wavelength region of 750 nm or more is given sensitivity, it may have absorption in such a wavelength region as a sensitizing dye. Particularly preferred examples which are necessary and used for such purposes are given below.

  The photosensitive composition of the present invention preferably contains a binder polymer. As such a polymer, an alkali-soluble polymer is preferable, and for that purpose, a polymer containing a carboxyl group-containing monomer as a copolymerization component is preferable. In this case, the proportion of the carboxyl group-containing monomer in the copolymer is preferably 5% by mass or more and 99% by mass or less, more preferably 10% by mass to 90% by mass with respect to 100% by mass of the total copolymer composition. The range of is preferable. If the ratio is less than this, the copolymer may not be dissolved in the alkaline aqueous solution.

  As the binder polymer preferably used in the present invention, a copolymer having a polymerizable double bond in the side chain and containing a carboxyl group-containing monomer as a copolymerization component is particularly preferable. Although the monomer for introducing a polymerizable double bond into the side chain of the copolymer will be described later, the copolymer total composition is determined as a ratio of the monomer having a polymerizable double bond in the side chain in the copolymer composition. It is preferable that it is 5 to 95 mass% with respect to 100 mass%, The range of 10-95 mass% is more preferable, Furthermore, the range of 20-90 mass% is preferable.

  Examples of the monomer for obtaining a polymer having a polymerizable double bond in the side chain include vinyl (meth) acrylate, vinyl (meth) acrylamide, allyl (meth) acrylate, allyl (meth) acrylamide, 1-propenyl- (Meth) acrylate, β-phenylvinyl- (meth) acrylate, α-chlorovinyl- (meth) acrylate, β-methoxyvinyl- (meth) acrylate, vinyl-thio- (meth) acrylate, etc. A polymer having a phenyl group substituted with vinyl as a polymerizable double bond is also preferably used.

  The polymer having a phenyl group with a vinyl group substituted on the side chain preferably used in the present invention is a polymer in which the phenyl group is bonded to the main chain directly or via a linking group, and the linking group is not particularly limited. Any group, atom, or a combination thereof may be mentioned. The phenyl group may be substituted with a substitutable group or atom, and the vinyl group is a halogen atom, a carboxy group, a sulfo group, a nitro group, a cyano group, an amide group, an amino group, an alkyl group, It may be substituted with an aryl group, an alkoxy group, an aryloxy group or the like. More specifically, the polymer having a phenyl group in which a vinyl group is substituted on the side chain described above has a group represented by the following general formula in the side chain.

In the formula, Z ⁴ represents a linking group, and R ⁴¹ and R ⁴² are a hydrogen atom, a halogen atom, a carboxy group, a sulfo group, a nitro group, a cyano group, an amide group, an amino group, or an alkyl having 1 to 4 carbon atoms. R ⁴³ represents a hydrogen atom, a halogen atom, a carboxy group, a sulfo group, a nitro group, a cyano group, an amide group, an amino group, an alkyl group, an aryl group or an alkoxy group. And an aryloxy group, and these groups may be substituted with an alkyl group, an amino group, an aryl group, an alkenyl group, a carboxy group, a sulfo group, a hydroxy group, or the like. R ⁴⁴ represents a substitutable group or atom. n4 is 0 or 1, m ₄ represents an integer of 0 to 4, k ₄ is an integer of 1-4. When m ₄ is 2 or more, R ⁴⁴ may be the same or different.

The above general formula will be described in more detail. As the linking group for Z ⁴ , an oxygen atom, a sulfur atom, an alkylene group, an alkenylene group, an arylene group, —N (R ⁴⁵ ) —, —C (O) —O—, —C (R ⁴⁶ ) ═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 ⁴⁵ and R ⁴⁶ represent a hydrogen atom, an alkyl group, an aryl group, or the like. Furthermore, the above 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 heterocyclic rings. Examples of groups represented by the above general formula are shown below, but are not limited to these examples.

Among the groups represented by the above general formula, there are preferable ones. That is, it is preferable that R ⁴¹ and R ⁴² are hydrogen atoms and R ⁴³ is a hydrogen atom or a lower alkyl group having 4 or less carbon atoms (methyl group, ethyl group, etc.). Further, the linking group preferably includes a heterocyclic ring, and k ₄ is preferably an integer of 1 to 4, m ₄ is an integer of 0 to 4, and n ₄ is 0 or 1.

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

  The binder polymer preferably used in the present invention is a multi-component copolymer by introducing other monomer components into the copolymer in addition to the above-mentioned monomer having a carboxyl group and a monomer having a polymerizable double bond in the side chain. Can be synthesized and used. 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, methacrylic acid-2-ethylhexyl, cyclohexyl methacrylate, methacrylic acid alkyl esters such as dodecyl methacrylate, phenyl methacrylate, benzyl methacrylate Methacrylic acid aryl esters or alkyl aryl esters such as 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, methoxydiethylene glycol methacrylate Contains amino groups such as monoester, methacrylic acid methoxypolyethylene glycol monoester, methacrylic acid polypropylene glycol monoester and other alkyleneoxy group-containing methacrylates, methacrylic acid-2-dimethylaminoethyl, methacrylic acid-2-diethylaminoethyl Examples similar to these corresponding methacrylic acid esters as methacrylic acid esters or acrylic acid esters, vinylphosphonic acid or the like as a monomer having a phosphoric acid group, or amino group-containing monomers such as allylamine or diallylamine, or Vinyl sulfonic acid and its salt, allyl sulfonic acid and its salt, methallyl sulfonic acid and its salt, styrene sulfonic acid and its salt, 2-acrylamido-2-methylpropane sulfo Monomers having a sulfonic acid group such as acids and salts thereof, monomers having a nitrogen-containing heterocyclic ring such as 4-vinylpyridine, 2-vinylpyridine, N-vinylimidazole, N-vinylcarbazole, or quaternary ammonium bases. As monomers having 4-vinylbenzyltrimethylammonium chloride, acryloyloxyethyltrimethylammonium chloride, methacryloyloxyethyltrimethylammonium chloride, quaternized product of dimethylaminopropylacrylamide with methyl chloride, quaternized product of N-vinylimidazole with methyl chloride, 4 -Vinylbenzylpyridinium chloride, etc., or acrylonitrile, methacrylonitrile, acrylamide, methacrylamide, dimethylacrylamide, Acrylamide or methacrylamide derivatives such as diethyl acrylamide, N-isopropyl acrylamide, diacetone acrylamide, N-methylol acrylamide, N-methoxyethyl acrylamide, 4-hydroxyphenyl acrylamide, acrylonitrile, methacrylonitrile, phenylmaleimide, hydroxyphenylmaleimide , Vinyl acetate, vinyl chloroacetate, vinyl propionate, vinyl butyrate, vinyl stearate, vinyl benzoate, etc., vinyl ethers such as methyl vinyl ether, butyl vinyl ether, others, N-vinylpyrrolidone, acryloylmorpholine, tetrahydro Furfuryl methacrylate, vinyl chloride, vinylidene chloride, allyl alcohol, vinyl trimeth Shishiran, it may be used glycidyl methacrylate and various monomers as arbitrary copolymerization monomers. As a ratio of these monomers in the copolymer, a preferable ratio of the monomer having a polymerizable double bond in the side chain and the carboxyl group-containing monomer in the copolymer composition described above is maintained. As long as it can be introduced at any ratio.

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

  Examples of copolymers having a phenyl group substituted with a vinyl group in the side chain preferably used in the present invention and having a carboxyl group-containing monomer as a copolymerization component are shown below. In the formula, the number represents the mass% of each repeating unit in the copolymer total composition of 100 mass%.

  Examples of binder polymers other than the above examples include polymers having a phenolic hydroxyl group, and polyvinylphenol, phenol resin, polyhydroxybenzal, and the like can also be used.

  10-90 mass% is suitable with respect to the whole composition of a photosensitive composition, and the content rate in the photosensitive composition of the binder polymer mentioned above has the preferable range of 20-80 mass%, especially 30-70 mass. % Range is preferred.

  The photosensitive composition of the present invention contains a radical generator. Known compounds can be used as the radical generator. For example, organic boron salts, trihaloalkyl-substituted compounds (for example, s-triazine compounds and oxadiazole derivatives as trihaloalkyl-substituted nitrogen-containing heterocyclic compounds, trihaloalkylsulfonyl compounds), hexaarylbisimidazoles, titanocene compounds, ketoximes Compounds, thio compounds, organic peroxides, onium salts (iodonium salts, diazonium salts, sulfonium salts described in JP-A-2003-114532) and the like. Among these radical generators, organic boron salts and trihaloalkyl-substituted compounds are particularly preferably used. More preferably, an organic boron salt and a trihaloalkyl-substituted compound are used in combination.

  The organic boron anion constituting the organic boron salt is represented by the following general formula.

In the formula, each of R ⁵¹ , R ⁵² , R ⁵³ and R ⁵⁴ may be the same or different, and represents an alkyl group, an aryl group, an aralkyl group, an alkenyl group, an alkynyl group, a cycloalkyl group or a heterocyclic group. To express. Of these, it is particularly preferred that one of R ⁵¹ , R ⁵² , R ⁵³ and R ⁵⁴ is an alkyl group and the other substituent is an aryl group.

  Examples of the cation constituting the organic boron salt include alkali metal ions and onium compounds, and preferred are onium salts such as ammonium salts such as tetraalkylammonium salts, sulfonium salts such as triarylsulfonium salts, and triaryls. Examples thereof include phosphonium salts such as alkylphosphonium salts. Examples of particularly preferred organic boron salts are shown below. The organic boron anion described above may be a counter anion of the sensitizing dye.

  Other preferred radical generators include trihaloalkyl substituted compounds. 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 below.

  The content of the radical generator as described above is preferably in the range of 10 to 1000% by mass, more preferably in the range of 20 to 500% by mass with respect to the sensitizing dye.

  In the photosensitive composition of the present invention, other components may be preferably added for various purposes in addition to the components described above. For example, for the purpose of improving the storage stability, it is preferable to add a hindered phenol compound or a hindered amine compound.

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

  The photosensitive composition of the present invention can be preferably used as a photosensitive layer of a lithographic printing plate. In this case, the thickness of the photosensitive layer itself is preferably formed on the support with a dry thickness in the range of 0.5 to 10 microns, and further in the range of 1 to 5 microns greatly improves printing durability. It is extremely preferable to improve it. The photosensitive layer is coated and dried on the support using various known coating methods. For example, a polyester film or polyethylene-coated paper may be used as the support, but a more preferable support is an aluminum plate that is polished and has an anodized film.

  In order to use the material having the photosensitive layer formed on the support as described above as a lithographic printing plate, it is subjected to contact exposure or laser scanning exposure, and the exposed portion is crosslinked to cause alkaline development. Since the solubility in the solution decreases, pattern formation is performed by eluting the non-exposed portion with an alkaline developer described later.

  The alkaline developer is preferably sodium hydroxide, potassium hydroxide, sodium silicate, potassium silicate, sodium metasilicate, potassium metasilicate, monoethanolamine, diethanolamine, triethanolamine, triethylammonium hydroxide, etc. An aqueous developer in which an alkaline compound is dissolved is extremely preferable because it can selectively dissolve the non-exposed portion and expose the lower support surface. 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 developer preferably further contains an anionic surfactant, which further improves the dissolution property. Examples of such anionic surfactants include higher fatty acid sulfates, alkyl naphthalene sulfonates, alkyl benzene sulfonates, and dialkyl sulfosuccinates. Among these, alkyl naphthalene sulfonates are preferable. The content of the anionic surfactant is preferably in the range of 1 to 50 g per liter of the developer, and particularly preferably in the range of 3 to 30 g.

  EXAMPLES Hereinafter, although an Example demonstrates this invention in detail, this invention is not limited to these Examples as well as the effect.

Synthesis of Photopolymerizable Monomer (M-12: Mercapto Group Residual Rate 10%) 8.7 g of pentaerythritol tetrakis (mercaptoacetate) [manufactured by Wako Pure Chemical Industries, Ltd.] was used, and chloromethylstyrene [Seimi Chemical Co., Ltd. ), CMS-P], changed to 11.0 g, mixed with 0.1 g of N-nitrosophenylhydroxylamine aluminum salt [Wako Pure Chemical Industries, Ltd.] and 50 ml of acetonitrile, and cooled with ice water and stirred. 7.7 g of triethylamine [manufactured by Nacalai Tesque Co., Ltd.] was added dropwise over 10 minutes. After completion of dropping, the mixture was cooled with ice water for 30 minutes, then returned to room temperature and further stirred for 2 hours. Subsequently, the solvent was distilled off from the reaction mixture under reduced pressure at a bath temperature of 40 ° C. or less, 50 ml of methanol was added to the residue, and the mixture was stirred at room temperature for 10 minutes. After standing, the supernatant was removed by decantation. Thereafter, this washing operation was repeated four times. Finally, 0.02 g of N-nitrosophenylhydroxylamine / aluminum salt [manufactured by Wako Pure Chemical Industries, Ltd.] was added, and the remaining solvent was distilled off under reduced pressure at a bath temperature of 35 ° C. or less. 14.2 g of M-12 (pale yellow oil) was obtained. In addition, the mercapto group residual ratio of this photopolymerizable monomer is as follows: mercapto group: 2.01 ppm (t) and vinyl group: 5.18-5.29 ppm (multi) in ¹ H-NMR (TMS / CDCl ₃ ); It was about 10% when calculated from an integrated intensity ratio of 66-5.78 ppm (multi) and 6.61-6.79 ppm (multi).

Synthesis of Photopolymerizable Monomer (M-16: Mercapto Group Residual Rate 10%) Pentaerythritol tetrakis (3-mercaptopropionate) [manufactured by Wako Pure Chemical Industries, Ltd.] 9.8 g, 4-chloromethylstyrene [Seimi Chemical Co., Ltd., CMS-14] 11.0 g, N-nitrosophenylhydroxylamine / aluminum salt [Wako Pure Chemical Industries, Ltd.] 0.1 g, 50 ml of acetonitrile were mixed and triethylamine was cooled with ice water and stirred. [Nacalai Tesque Co., Ltd.] 7.7g was dripped over 10 minutes. After completion of dropping, the mixture was cooled with ice water for 30 minutes, then returned to room temperature and further stirred for 5 hours. Subsequently, the solvent was distilled off from the reaction mixture under reduced pressure at a bath temperature of 40 ° C. or less, 50 ml of methanol was added to the residue, and the mixture was stirred at room temperature for 10 minutes. After standing, the supernatant was removed by decantation. Thereafter, this washing operation was repeated four times. Finally, 0.02 g of N-nitrosophenylhydroxylamine / aluminum salt [manufactured by Wako Pure Chemical Industries, Ltd.] was added, and the remaining solvent was distilled off under reduced pressure at a bath temperature of 35 ° C. or less. 15.8 g of M-16 (pale yellow oil) was obtained. In addition, the mercapto group residual ratio of this photopolymerizable monomer was calculated to be about 10% in the same manner as M-12 described above.

Synthesis of Photopolymerizable Monomer (M-17: Mercapto Group Residual Rate 12%) Dipentaerythritol [manufactured by Tokyo Chemical Industry Co., Ltd.] 25.4 g, thioglycolic acid [manufactured by Tokyo Chemical Industry Co., Ltd.] 55.3 g, 1.5 g of p-toluenesulfonic acid monohydrate [manufactured by Nacalai Tesque Co., Ltd.] and 300 ml of toluene were mixed, and heated and refluxed for 8 hours while removing by-product water azeotropically. Then, toluene was distilled off under reduced pressure, and the residue was chloromethylstyrene [Seimi Chemical Co., Ltd., CMS-P] 76.3 g, N-nitrosophenylhydroxylamine aluminum salt [Wako Pure Chemical Industries, Ltd.] 0 0.5 g and 500 ml of acetonitrile were added, and 60.7 g of triethylamine [manufactured by Nacalai Tesque Co., Ltd.] was added dropwise over 30 minutes while cooling with ice water and stirring. After completion of dropping, the mixture was cooled with ice water for 30 minutes, then returned to room temperature and further stirred for 2 hours. Subsequently, the solvent was distilled off from the reaction mixture under reduced pressure at a bath temperature of 40 ° C. or less, 500 ml of methanol was added to the residue, and the mixture was stirred at room temperature for 10 minutes. After standing, the supernatant was removed by decantation. Thereafter, this washing operation was repeated four times. Finally, 0.1 g of N-nitrosophenylhydroxylamine / aluminum salt [manufactured by Wako Pure Chemical Industries, Ltd.] was added, and the remaining solvent was distilled off under reduced pressure at a bath temperature of 35 ° C. or less. And 117.2 g of M-17 (pale yellow oil) was obtained. In addition, the mercapto group residual ratio of this photopolymerizable monomer is as follows: mercapto group: 2.01 ppm (t) and vinyl group: 5.18-5.29 ppm (multi) in ¹ H-NMR (TMS / CDCl ₃ ); It was about 12% calculated from the integrated intensity ratio of 66-5.78 ppm (multi) and 6.61-6.79 ppm (multi).

Synthesis of Photopolymerizable Monomer (M-37: Mercapto Group Residual Ratio: 12%) 2.19 g of triethylenetetramine [manufactured by Tokyo Chemical Industry Co., Ltd.] and 6.68 g of triethylamine [manufactured by Nacalai Tesque Co., Ltd.] in 30 ml of methanol A solution prepared by dissolving 5.02 g of carbon disulfide [manufactured by Nacalai Tesque Co., Ltd.] in 15 ml of methanol was added dropwise over 10 minutes while stirring while cooling with ice water. After completion of dropping, the mixture was cooled with ice water for 30 minutes, then returned to room temperature and further stirred for 1 hour. To the obtained yellowish white suspension, 0.2 g of N-nitrosophenylhydroxylamine / aluminum salt [manufactured by Wako Pure Chemical Industries, Ltd.] was added and stirred while cooling with ice water, while 4-chloromethylstyrene [Seimi Chemical ( Co., Ltd., CMS-14] 8.06 g was added dropwise over 15 minutes. After completion of the dropwise addition, stirring was continued for 2 hours at room temperature. After the reaction was completed, the precipitated crystals were filtered and washed thoroughly with methanol and water. This was dried to obtain 7.3 g of a photopolymerizable monomer (M-37: mercapto group residual ratio 12%).

Synthesis of photopolymerizable monomer (M-49: mercapto group residual ratio 20%) Intermediate (IM-2) 1.30 g described in Example 1 of Japanese Patent Application No. 2003-093262, 4-tert-butylcatechol [Tokyo Kasei Co., Ltd. [Industry Co., Ltd.] 0.01 g and methanol 15 ml were charged into a flask, and an aqueous solution in which 0.53 g of potassium hydroxide was dissolved in 1.5 ml of water was added while stirring at room temperature. While stirring the obtained amber-colored uniform solution at room temperature, 0.95 g of 4-chloromethylstyrene [manufactured by Seimi Chemical Co., Ltd., CMS-14] was added. Stirring was continued at 55 ° C. for 3 hours. After completion of the reaction, the supernatant was discarded by decantation, the residue was dissolved in chloroform, transferred to a separatory funnel, and washed with water. The organic layer was separated and dried over anhydrous sodium sulfate. After filtration, the filtrate was evaporated under reduced pressure and produced by silica gel column chromatography to obtain 1.45 g of M-49 (mercapto group residual ratio 20%) as a pale yellow solid on wax.

Synthesis of photopolymerizable monomer (M-91: mercapto group residual ratio 15%) Intermediate (IM-4) 4.89 g described in Example 6 of Japanese Patent Application No. 2003-093262, 4-tert-butylcatechol [Tokyo Kasei Co., Ltd.] Industrial Co., Ltd.] 0.05 g and methanol 50 g were charged into a flask, and triethylamine [Nacalai Tesque Co., Ltd.] 6.68 g was added while stirring at room temperature. While stirring the obtained pale yellow uniform solution at room temperature, 6.04 g of 4-chloromethylstyrene [manufactured by Seimi Chemical Co., Ltd., CMS-14] was added. The reaction was carried out at 50 ° C. for 3 hours. After completion of the reaction, 15 ml of 2N hydrochloric acid was added to the reaction solution to cause crystallization. The crystals were collected by filtration, washed with methanol and dried to obtain 6.5 g of M-91 (mercapto group residual ratio 15%) as a pale yellow solid.

[Comparative Example 1]
Synthesis of photopolymerizable monomer (M-12: residual ratio of mercapto group 3%) Pentaerythritol tetrakis (mercaptoacetate) [manufactured by Wako Pure Chemical Industries, Ltd.] 8.7 g, chloromethylstyrene [manufactured by Seimi Chemical Co., Ltd., CMS-P] 11.5 g, N-nitrosophenylhydroxylamine / aluminum salt [manufactured by Wako Pure Chemical Industries, Ltd.] 0.1 g and 50 ml of acetonitrile were mixed, and triethylamine [Nacalai Tesque Co., Ltd.] was cooled with ice water and stirred. 7.7 g] was added dropwise over 10 minutes. After completion of dropping, the mixture was cooled with ice water for 30 minutes, then returned to room temperature and further stirred for 2 hours. Subsequently, the solvent was distilled off from the reaction mixture under reduced pressure at a bath temperature of 40 ° C. or less, 50 ml of methanol was added to the residue, and the mixture was stirred at room temperature for 10 minutes. After standing, the supernatant was removed by decantation. Thereafter, this washing operation was repeated four times. Finally, 0.02 g of N-nitrosophenylhydroxylamine / aluminum salt [manufactured by Wako Pure Chemical Industries, Ltd.] was added, and the remaining solvent was distilled off under reduced pressure at a bath temperature of 35 ° C. or less. Further, 14.2 g of M-12 (pale yellow oily substance) was obtained. The residual ratio of the mercapto group of this photopolymerizable monomer was as follows: mercapto group in ¹ H-NMR (TMS / CDCl ₃ ): 2.01 ppm (t ) And vinyl group: calculated from an integral intensity ratio of 5.18-5.29 ppm (multi), 5.66-5.78 ppm (multi), and 6.61-6.79 ppm (multi), and was about 3%. It was.

[Comparative Example 2]
Synthesis of photopolymerizable monomer (M-12: mercapto group residual ratio 50%) Pentaerythritol tetrakis (mercaptoacetate) [manufactured by Wako Pure Chemical Industries, Ltd.] 8.7 g, chloromethylstyrene [manufactured by Seimi Chemical Co., Ltd., CMS-P] 6.0 g, N-nitrosophenylhydroxylamine / aluminum salt [manufactured by Wako Pure Chemical Industries, Ltd.] 0.1 g and 50 ml of acetonitrile were mixed, and triethylamine [Nacalai Tesque Co., Ltd.] was cooled with ice water and stirred. 7.7 g] was added dropwise over 10 minutes. After completion of dropping, the mixture was cooled with ice water for 30 minutes, then returned to room temperature and further stirred for 2 hours. Subsequently, the solvent was distilled off from the reaction mixture under reduced pressure at a bath temperature of 40 ° C. or less, 50 ml of methanol was added to the residue, and the mixture was stirred at room temperature for 10 minutes. After standing, the supernatant was removed by decantation. Thereafter, this washing operation was repeated four times. Finally, 0.02 g of N-nitrosophenylhydroxylamine / aluminum salt [manufactured by Wako Pure Chemical Industries, Ltd.] was added, and the remaining solvent was distilled off under reduced pressure at a bath temperature of 35 ° C. or less. 14.2 g of M-12 (pale yellow oil) was obtained. In addition, the mercapto group residual ratio of this photopolymerizable monomer is as follows: mercapto group: 2.01 ppm (t) and vinyl group: 5.18-5.29 ppm (multi) in ¹ H-NMR (TMS / CDCl ₃ ); It was about 50% when calculated from the integral intensity ratio of 66-5.78 ppm (multi) and 6.61-6.79 ppm (multi).

[Comparative Example 3]
Synthesis of Photopolymerizable Monomer (M-37: Mercapto Group Residual Rate 0%) Triethylenetetramine [Tokyo Chemical Industry Co., Ltd.] 2.19 g and triethylamine [Nacalai Tesque Co. Ltd.] 6.68 g in 30 ml of methanol A solution prepared by dissolving 5.02 g of carbon disulfide [manufactured by Nacalai Tesque Co., Ltd.] in 15 ml of methanol was added dropwise over 10 minutes while stirring while cooling with ice water. After completion of dropping, the mixture was cooled with ice water for 30 minutes, then returned to room temperature and further stirred for 1 hour. To the obtained yellowish white suspension, 0.2 g of N-nitrosophenylhydroxylamine / aluminum salt [manufactured by Wako Pure Chemical Industries, Ltd.] was added and stirred while cooling with ice water, while 4-chloromethylstyrene [Seimi Chemical ( Co., Ltd., CMS-14] 9.16 g was added dropwise over 15 minutes. After completion of the dropwise addition, stirring was continued for 2 hours at room temperature. After completion of the reaction, the precipitated crystals were filtered and repeated on the line with methanol and water. This was dried to obtain 8.32 g of a photopolymerizable monomer (M-37: mercapto group residual ratio 0%).

A coating solution of a photosensitive composition having the following composition was prepared. Next, the coating solution is applied on a grained and anodized aluminum plate having a thickness of 0.24 mm so as to have a dry thickness of 2.0 μm, and dried at 75 ° C. for 5 minutes. Produced. Table 1 shows the sample contents. In Table 1, monomer CM-3 as a comparative example is described in Patent Document 6.
<Coating liquid>
Binder resin (P-1: mass average molecular weight of about 50,000) 6.0 parts by mass Photopolymerization initiator (BC-6) 1.0 part by mass Photopolymerization initiator (T-4) 0.2 part by mass Photopolymerizable monomer (monomer of the present invention and comparative monomer below) 1.5 parts by mass Sensitizing dye (S-39) 0.3 part by weight Basic Blue 7 0.1 part by mass 1,4-dioxane 45.0 Parts by mass

  A part of the sample obtained above was left in a room with a temperature of 35 ° C. and a relative humidity of 80% for 2 weeks to obtain a sample with forced heating over time.

The printing performance of the sample obtained above as a lithographic printing plate was evaluated. Using an image setter (manufactured by Dainippon Screen Mfg. Co., Ltd., PTR-4000) equipped with a semiconductor laser emitting at 830 nm, exposure was performed at 2400 dpi, drum rotation speed 1000 rpm, and plate surface exposure energy 100 mJ / cm ² . After the exposure, PD912 (manufactured by Dainippon Screen Mfg. Co., Ltd.) is used as an automatic developing machine, and development is performed at 30 ° C. for 15 seconds with the following developer, followed by application of the following gum solution, and a negative lithographic printing plate Got.

<Developer>
35% sodium alkylnaphthalene sulfonate (manufactured by Kao Corporation) 30g
25% tetraalkylammonium hydroxide 50g
Phosphoric acid 10g
N-ethylethanolamine 30g
EDTA2Na 1g
1L with water
<Gum solution>
Monopotassium phosphate 10g
Gum arabic 25g
Sodium dehydroacetate 0.5g
EDTA2Na 1g
1L with water

  The plate obtained by the above-described method was attached to an offset printing machine (manufactured by Ryobi Co., Ltd .; Ryobi 560) with a 50 μm gauge film spread, and printing was performed under conditions of higher printing pressure than usual. The ink used was [Dainippon Ink Chemical Co., Ltd .; FINE INK New Champion Ink (N)] and the dampening solution was [Nikken Chemical Co., Ltd .; 1% aqueous solution of Astro Mark III]. . The results are shown in Table 2. The printing durability in Table 2 is a three-stage evaluation of ˜150,000 sheets: ◯, ˜70,000 sheets: Δ, 30,000 sheets or less: x. Further, the samples left in the hot and humid room under the above conditions were developed under the same conditions, and the elution properties of the plate-making products were evaluated. The results are shown in Table 2. The evaluation criteria are 6 points on the surface of the non-image area observed with a magnifying glass 50 times, and ○ when the photosensitive layer is not observed at all, Δ when the photosensitive layer is observed at 1 to 2 points, and × when 3 points or more are observed. And

  As can be seen from Table 2, in the sample to which the monomer of the comparative example was added, the dissolution property was poor or the printing durability was poor by storage at high temperature and high humidity, but in the sample to which the monomer of the present invention was added, the temperature was high. Elution is not deteriorated even when stored under humidity, and printing durability is also good.

  Examples of use of the present invention include photosensitive resins, printing plates, inks, paints, adhesives, cross-linking agents, optical lens materials, optical fiber coatings, three-dimensional modeling, holographic recording materials, printed wiring boards and electronic materials such as ICs. Application.

Claims (5)

A photopolymerizable monomer having two or more unit structures represented by the following general formula 1 in the molecule, a photopolymerizable monomer having two or more unit structures represented by the following general formula 3 in the molecule, A polymerizable monomer selected from the photopolymerizable monomer represented by formula (7) and the photopolymerizable monomer represented by formula (7), wherein the residual ratio of -SH of the photopolymerizable monomer is 5 to 45%. A photopolymerizable monomer.

In General Formula 1, L ¹ represents a divalent linking group, and A represents a hydrogen atom or a structure of the following General Formula 2.

In General Formula 2, L ² represents a divalent linking group, and VP represents a phenyl group substituted with a vinyl group.

In General Formula 3, A ₁₀ represents a hydrogen atom or a structure of the following General Formula 4.

In General Formula 4, L ¹¹ represents a divalent linking group consisting of an atom or a group of atoms selected from a hydrogen atom, a carbon atom, a nitrogen atom, an oxygen atom, and a sulfur atom, and VP represents a phenyl group substituted with a vinyl group. . n1 represents 0 or 1.

In the general formula 5, L ²¹ represents a polyvalent linking group consisting of an atom or a group of atoms selected from a hydrogen atom, a carbon atom, a nitrogen atom, an oxygen atom, and a sulfur atom. A ₂₀ and A ₂₁ each represent a hydrogen atom or a structure of the following general formula 6, and may be the same or different.

In General Formula 6, L ²² represents a polyvalent linking group consisting of an atom or a group of atoms selected from a hydrogen atom, a carbon atom, a nitrogen atom, an oxygen atom, and a sulfur atom. Y ²¹ may be the same or different and represents a phenylene group or —CO— group which may have a substituent. n ₂₁ represents 0 or 1. R ²¹ , R ²² and R ²³ may be the same or different and are each a hydrogen atom, a halogen atom, a carboxyl group, a sulfo group, a nitro group, a cyano group, an amide group, an amino group, an alkyl group, or an aryl group. Represents a group selected from an alkoxy group, an aryloxy group, an alkylthio group, an arylthio group, an alkylamino group, an arylamino group, an acyl group, an alkoxycarbonyl group, an aryloxycarbonyl group, an alkylsulfonyl group, and an arylsulfonyl group.

In general formula 7, A ₃₀ and A ₃₁ each represent a hydrogen atom or the structure of general formula 8 below, and R ³⁴ and R ^{35 which} may be the same or different may be the same or different, A hydrogen atom, an alkyl group, an alkenyl group, an aryl group and a heterocyclic group are represented. Further, R ³⁴ and R ³⁵ may be combined to form a ring structure. A ₃₀ and A ₃₁ each represent a hydrogen atom or a structure of the following general formula 8, and may be the same or different.

In the general formula 8, R ³¹ , R ³² , and R ³³ are synonymous with R ²¹ , R ^22, and R ²³ , respectively. L ³¹ has the same meaning as L ²² in formula 3. Y ³¹ is synonymous with Y ²¹ . n ₃₁ represents 0 or 1, respectively.   A photosensitive composition comprising the photopolymerizable monomer according to claim 1.   Furthermore, the photosensitive composition of Claim 2 containing a photoinitiator.   4. The photosensitive composition according to claim 2, comprising the photopolymerizable monomer according to claim 1, a photopolymerization initiator, and a sensitizing dye that sensitizes in the wavelength range of 380 to 1100 nm.   A lithographic printing plate characterized in that the photosensitive composition according to any one of claims 2 to 4 is used for a photosensitive layer provided on a support.