JP2016071044A - Photosensitive resin composition for relief printing and photosensitive resin relief printing plate precursor obtained from the composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a photosensitive resin composition for relief printing, which exhibits high-quality printing with little ink fill-in while maintaining high image reproducibility.SOLUTION: The photosensitive resin composition for relief printing comprises, as essential components, at least a water-soluble polymeric compound, a photopolymerizable unsaturated compound, and a photopolymerization initiator. The water-soluble polymeric compound is a co-polycondensate obtained by a polycondensation reaction of (A) an ω-amino acid or its lactam, (B) a hydrophilic diamine, (C) a hydrophobic diamine, (D) an amino-modified silicone compound, and (E) a dicarboxylic acid.SELECTED DRAWING: None

Description

  The present invention relates to a water-developable photosensitive resin composition, and more specifically, to a water-developable letterpress printing photosensitive resin composition with less ink entanglement, and a water-developable letterpress printing printing original plate obtained therefrom. Is.

  In the water-developable photosensitive resin composition used for the printing plate, generally, a water-soluble polymer compound, a photopolymerizable unsaturated group-containing monomer, and a photopolymerization initiator are contained as essential components, and if necessary, stable Additives such as plasticizers and plasticizers are blended. As water-developable photosensitive resin compositions, those using water-developable polyamide, polyether urea urethane, fully saponified or partially saponified polyvinyl acetate as water developable polymers have been proposed. A photosensitive resin composition using urea urethane is particularly preferably used because of its excellent wear resistance.

  The printing method using the photosensitive resin printing plate for letterpress printing is a method in which ink is supplied to the convex surface of an uneven resin relief plate with an ink supply roll, and then the ink on the convex surface is transferred to the printing medium. It is. In such printing, when printing is performed for a long time, the ink often adheres to the shoulder portion of the convex portion of the resin plate or the ink enters the concave portion (hereinafter referred to as ink entanglement). Occur. As a result, a portion that is not the original pattern may be printed, resulting in a decrease in print quality.

  Particularly, in recent years, the application of letterpress printing to high-definition printing has progressed, and halftone dot printing with a high number of lines has been actively performed in order to produce color and density gradation. In this case, since the interval between the halftone dots is smaller, the ink is more likely to be clogged between the halftone dots of the printing plate, and ink entanglement occurs as a more severe problem. If the ink accumulates above a certain level in the valleys of the printing plate, these transfer to the printing material and cause dot entanglement, resulting in a significant reduction in printing quality. Therefore, there is a demand for a printing plate with less ink entanglement in order to improve printing quality.

  As a conventional technique corresponding to these requirements, a method of blending a water repellent such as a silicone compound or a fluorine compound with a water-developable photosensitive resin composition has been studied. What is a photosensitive resin composition? The compatibility was poor. Therefore, if an amount necessary for obtaining a water repellent effect is added, the photosensitive resin layer becomes opaque or the water repellent bleeds out during storage of the original plate, and only a poor quality print plate can be obtained. It was.

  On the other hand, as another method of using a water repellent having poor compatibility with the photosensitive resin composition, a method of surface treatment with a water repellent is proposed during or after the production of a printing original plate (see Patent Document 1). Yes. However, the production method of Patent Document 1 is a method in which a water repellent is brought into contact with a treatment solution in which a solvent such as alcohol is dissolved, dried and irradiated with actinic rays. In this method, complicated work is required, and a method for improving ink entanglement that does not require special treatment has been demanded.

International Publication No. 2005/06441

  The present invention has been made in view of the circumstances of the prior art as described above, and is obtained from a high-quality photosensitive resin composition for letterpress printing with less ink entanglement while maintaining high image reproducibility. An object is to provide a printing original plate for letterpress.

  As a result of intensive studies to achieve the above object, the present inventors have obtained a print obtained by using a photosensitive resin composition containing a polyamide containing a specific amount of an amino-modified silicone compound in a photosensitive resin relief plate material. The knowledge that the original plate can achieve excellent ink entanglement property while maintaining high image reproducibility was obtained, and the present invention was completed based on the knowledge.

That is, the present invention has the following configurations (1) to (5).
(1) A photosensitive resin composition for letterpress printing containing at least a water-soluble polymer compound, a photopolymerizable unsaturated compound, and a photopolymerization initiator as essential components, wherein the water-soluble polymer compound is (A A copolycondensate obtained by a polycondensation reaction of ω-amino acid or a lactam thereof, (B) a hydrophilic diamine, (C) a hydrophobic diamine, (D) an amino-modified silicone compound, and (E) a dicarboxylic acid. A photosensitive resin composition for letterpress printing.
(2) The photosensitive resin composition for letterpress printing according to (1), wherein the amino group equivalent of the (D) amino-modified silicone compound is in the range of 100 g / mol to 10,000 g / mol.
(3) (D) The amino-modified silicone compound is amino-modified at both ends, and the ratio of each component to the total amount of the components (A) to (E) is as follows: The photosensitive resin composition for letterpress printing according to (1) or (2).
(A) ω-amino acid or lactam thereof 40-60% by mass
(B) Hydrophilic diamine 15-30% by mass
(C) Hydrophobic diamine 2-8% by mass
(D) Amino-modified silicone compound 0.1-20% by mass
(E) Dicarboxylic acid 15-30 mass%
(4) (A) The hydrophilic diamine is at least one selected from the group consisting of N, N′-bis (3-aminopropyl) piperazine and N, N′-bis (3-aminopropyl) methylamine. The photosensitive resin composition for letterpress printing according to any one of (1) to (3), wherein:
(5) A printing plate precursor for letterpress printing, comprising a photosensitive resin layer comprising the photosensitive resin composition for letterpress printing according to any one of (1) to (4).

  The photosensitive resin composition for letterpress printing of the present invention is excellent in ink releasability while maintaining high image reproducibility by copolymerizing a specific silicone compound in the water-soluble polymer compound in the composition. Even in long-run printing, there is very little adhesion to the relief wall surface, and there is an effect that printing defects due to ink entanglement are hardly exhibited.

  The photosensitive resin composition for letterpress printing of the present invention contains at least a water-soluble polymer compound, a photopolymerizable unsaturated compound, and a photopolymerization initiator as essential components, and the water-soluble polymer compound is (A) It is a copolycondensate obtained by a polycondensation reaction of an ω-amino acid or a lactam thereof, (B) a hydrophilic diamine, (C) a hydrophobic diamine, (D) an amino-modified silicone compound, and (E) a dicarboxylic acid. Features.

  Examples of the ω-amino acid or lactam (A) used for the water-soluble polymer compound include ω-amino acids such as aminocaproic acid, aminoheptanoic acid, aminocaprylic acid, and aminolauric acid, or lactams thereof. Among them, ε-caprolactam is particularly preferable. By using these ω-amino acids or their lactams as a copolymerization component, these structural units can be introduced into the polyamide. Moreover, this invention can obtain the printing plate with favorable abrasion resistance which is the characteristic of polyamide by containing (A) component 40-60 mass%.

  As the hydrophilic diamine (B) used for the water-soluble polymer compound, tertiary nitrogen such as N, N′-bis (3-aminopropyl) piperazine, N- (2-aminoethyl) piperazine is contained in the structure. Examples thereof include diamines, polyoxyethylene glycols substantially having amino groups added to both ends, copolymers of polyoxyethylene glycols, and diamines having sulfonic acid groups. Among them, diamines containing tertiary nitrogen in the structure such as N, N′-bis (3-aminopropyl) piperazine and N- (2-aminoethyl) piperazine are preferable.

  The hydrophobic diamine (C) used for the water-soluble polymer compound is ethylenediamine, diethylenediamine, 1,3-propylenediamine, 1,4-tetramethylenediamine, 2-methylpentamethylenediamine, 1,6-hexanemethylenediamine. 1,11-undecamethylenediamine, 1,4-bis (aminomethyl) cyclohexane, 1,3-bis (aminomethyl) cyclohexane, 1,4-bis-aminocyclohexane, 1,3-aminocyclohexane, etc. Can be mentioned. Among them, those having a cyclohexane ring are preferable, and 1,3-bis- (aminomethyl) cyclohexane is particularly preferable.

  The amino-modified silicone compound (D) used for the water-soluble polymer compound is a silicone compound having at least one amino group in the molecule. As for the position of the amino group, there are a side chain type, a terminal type, a side chain terminal type that exists in both the side chain and the terminal, and the like. Regarding the number of amino groups, there are not only monoamines or diamines but also those having 3 or more in the molecule, and various combinations with amino group positions are possible. Specifically, as the amino-modified silicone compound (C), a side-chain monoamine-modified amino-modified silicone compound, a side-chain diamine-modified amino-modified silicone compound, a single-end amine-modified amino-modified silicone compound, both ends Examples thereof include an amino-modified silicone compound modified with a type diamine, and an amino-modified silicone compound modified with an amine-modified side chain at both ends. Those having two amino groups in the molecule are preferred, and a diamino-modified silicone compound having both terminal types is particularly preferred. The amino equivalent of the amino-modified silicone compound (C) is preferably in the range of 100 g / mol to 10,000 g / mol, more preferably in the range of 100 g / mol to 6,000 g / mol.

  As the amino-modified silicone compound (D), for example, the following products can be obtained from the market. For example, examples of the side chain type monoamine type include KF-868 and KF-864 manufactured by Shin-Etsu Chemical Co., Ltd., and examples of the side chain type diamine type include KF-859, KF-393 and KF manufactured by Shin-Etsu Chemical Co., Ltd. -860, KF-880, KF-8004, KF-867, KF-869, KF-861 and the like. Examples of the both-end diamine type include PAM-E, KF-8010, X-22-161A, X-22-161B, KF-8008 and the like manufactured by Shin-Etsu Chemical Co., Ltd. Examples of the amino-modified silicone compound modified with amine at both ends of the side chain include KF-862 manufactured by Shin-Etsu Chemical Co., Ltd. Among the above amino-modified silicone compounds, from the viewpoint of polymerizing to a polymer as a diamine component, the amino group is preferably located at the terminal, and more preferably a double-terminal diamino-modified silicone compound containing two functional groups in the molecule. . By using a double-terminal diamino-modified silicone as a diamine component, it can be introduced into a water-soluble polymer compound. As a result, the silicone compound does not migrate to paper or ink, and the effect can be maintained for a long time. . Moreover, since it becomes difficult for a silicone compound to carry out phase separation, the photopolymerization inhibition by light scattering does not occur easily, and the compounding ratio of a silicone compound can be increased.

  The dicarboxylic acid (E) used for the water-soluble polymer compound should be present in an equimolar amount with respect to the total number of moles of the diamines of the components (B) to (D) in order to increase the molecular weight of the resulting polymer compound. Is preferred. In order to control the molecular weight of the resulting polymer compound, polymerization may be carried out with a slight excess of diamino or carboxylic acid. Specific examples of the dicarboxylic acid include succinic acid, adipic acid, glutaric acid, azelaic acid, sebacic acid, decanedicarboxylic acid, terephthalic acid, isophthalic acid, and cyclohexanedicarboxylic acid, and adipic acid is particularly preferable. .

In this invention, it is preferable that the ratio of each component with respect to the total amount of (A), (B), (C), (D), and (E) is the following ratio.
(A) ω-amino acid or lactam thereof 40-60% by mass
(B) Hydrophilic diamine 15-30% by mass
(C) Hydrophobic diamine 2-8% by mass
(D) Amino-modified silicone compound 0.1-20% by mass
(Preferably both terminal type diamino modified silicone compound)
(E) Dicarboxylic acid 15-30 mass%
More preferably, the blending amount of (D) amino-modified silicone is 0.5 to 10% by mass.

  When the component (A) is less than 40% by weight, the crystallinity of the polymer is lowered, the moldability of the resin composition is hindered, and the mechanical strength of the photocured part may not be sufficiently increased. On the other hand, when the amount is more than 60% by weight, the hydrophilicity of the polymer is lowered and the water developability may be lowered. When the component (B) is less than 15% by weight, the hydrophilicity of the polymer is lowered and the water developability is hindered. When the component is more than 30% by weight, the hydrophilicity of the polymer becomes too high, and the machine of the photocured portion after development There is a risk that the mechanical strength will be insufficient. If the component (C) is less than 2% by weight, light scattering during exposure cannot be sufficiently reduced, and if it is more than 8% by weight, the crystallinity and hydrophilicity of the polymer may be lowered.

  The photopolymerizable unsaturated compound used in the present invention is a compound containing one or more unsaturated groups capable of photopolymerization in the molecule, and conventionally known compounds can be used. Such compounds include (meth) acrylic acid, cyclohexyl (meth) acrylate, benzyl (meth) acrylate, N, N′-dimethylaminoethyl (meth) acrylate, aliphatic carboxylic acids (anhydrides) and 2- Ring-opening addition reaction of monoester carboxylic acid, glycidyl (meth) acrylate, (meth) acrylamide, N-methylol (meth) acrylamide, glycidyl (meth) acrylate and monoalcohol obtained by reaction with hydroxyethyl (meth) acrylate , Compounds having one unsaturated bond such as 2-acrylamido-2-methylpropanesulfonic acid, or ethylene glycol di (meth) acrylate, 1,3-propanediol dimeth) acrylate, 1,4-butanediol Di (meth) acrylate, , 6-hexanediol di (meth) acrylate, trimethylolethane di (meth) acrylate, trimethylolethane tri (meth) acrylate, trimethylolpropane di (meth) acrylate, trimethylolpropane tri (meth) acrylate, tetramethylolmethane Ring-opening addition reaction product of poly (glycidyl ether) of di (meth) acrylate polyhydric alcohol and (meth) acrylic acid, for example, reaction product of (poly) ethylene glycol diglycidyl ether and (meth) acrylic acid, (poly ) Reaction product of propylene glycol diglycidyl ether and (meth) acrylic acid, reaction product of 1,6-hexamethylene glycol diglycidyl ether and (meth) acrylic acid, glycerin diglycidyl ether and (meth) Acry Reaction products with acids, reaction products of trimethylolpropane triglycidyl ether and (meth) acrylic acid, ring-opening addition reaction products of other active hydrogen compounds with glycidyl (meth) acrylate, such as (poly) ethylene Reaction product of glycol and glycidyl (meth) acrylate, reaction product of (poly) propylene glycol and glycidyl (meth) acrylate, reaction product of glycerin and glycidyl (meth) acrylate, 2-hydroxyethyl (meth) Reaction product of acrylate and glycidyl (meth) acrylate, reaction product of trimethylolethane and glycidyl (meth) acrylate, reaction product of trimethylolpropane and glycidyl (meth) acrylate, (meth) acrylic acid and glycidyl (Meth) acrylate Products obtained by reaction with glycidyl (meth) acrylate, a reaction product of aliphatic polycarboxylic acid and glycidyl (meth) acrylate, a compound having a primary or secondary amino group and glycidyl (meth) acrylate Compounds having the above unsaturated groups, compounds having two or more unsaturated bonds such as N, N′-methylenebis (meth) acrylamide, N, N′-ethylenebis (meth) acrylamide, 5-methyl, 5-ethylhydantoin Is mentioned.

  Although the said photopolymerizable unsaturated compound may be used independently, you may use 2 or more types together. The amount of the photopolymerizable unsaturated compound used is preferably 10 to 150 parts by mass, particularly preferably 30 to 100 parts by mass with respect to 100 parts by mass of the water-soluble polymer compound in the composition. If the amount of the photopolymerizable unsaturated compound used is less than 10 parts by mass, the reproducibility of the exposed part with respect to the solvent is not sufficient, so that the image reproducibility is poor. There is a risk that the mechanical strength and developability will decrease.

  As the photopolymerization initiator used in the present invention, conventionally known photopolymerization initiators can be used. Specifically, for example, benzophenones, benzoins, acetophenones, benzyls, benzoin alkyl ethers, benzyl alkyl ketals Anthraquinones and thioxanthones can be used. Specific examples include benzophenone, benzoin, acetophenone, benzoin methyl ether, benzoin ethyl ether, benzyldimethyl ketal, anthraquinone, 2-chloroanthraquinone, thioxanthone, 2-chlorothioxanthone and the like. These are preferably contained in the photosensitive resin composition in an amount of 0.05 to 5% by mass. When the amount is less than 0.05% by mass, the photopolymerization initiation ability is hindered. When the amount is more than 5% by mass, the photocurability in the thickness direction of the printing plate in the case of producing a relief for printing is reduced, and the image is not chipped. It tends to happen.

  Further, if necessary, a known thermal polymerization inhibitor may be added. The thermal polymerization inhibitor is added in order to prevent unscheduled thermal polymerization due to heating during preparation, production, molding, etc. of the photosensitive resin letterpress composition, or dark reaction during storage of the composition. Examples of such compounds include hydroquinones such as hydroquinone, mono-tert-butylhydroquinone, 2,5-di-tert-butylhydroquinone, hydroquinone monomethyl ether, benzoquinone, and 2,5-diphenyl-p-benzoquinone. Catechols such as benzoquinones, phenols, catechol, p-tert-butylcatechol, aromatic amine compounds, picric acids, phenothiazine, α-naphthoquinones, anthraquinones, nitro compounds, sulfur compounds, etc. . The amount of the thermal polymerization inhibitor used is preferably from 0.001 to 2% by mass, particularly preferably from 0.005 to 1% by mass, based on the total composition. Two or more of these compounds may be used in combination.

  The photosensitive resin composition of the present invention can be obtained as a target product by any known method such as hot pressing, casting, melt extrusion, solution casting, etc., in addition to the melt molding method for obtaining a printing relief plate. It can be molded into a desired shape.

  When a relief plate for printing is obtained, a molded product (raw plate) formed into a sheet shape can be used by being laminated on a support with or without a known adhesive. As the support, any material such as steel, aluminum, glass, a plastic film such as a polyester film, and a metal-deposited film can be used. When a sheet-like molded product (raw plate) is supplied as a laminate laminated on a support, a protective layer is further laminated in contact with the sheet-like molded product (raw plate). As the protective layer, a film-like plastic, for example, a polyester film having a thickness of 1 to 3 μm coated with a non-sticky transparent polymer dispersed or dissolved in a developer is used. By contacting the protective layer having a thin polymer film with the sheet-like molded product (raw plate), the protection performed during the next exposure operation even when the surface-like property of the sheet-shaped molded product (raw plate) is strong. Peeling of the layer can be easily performed.

  A photosensitive resin letterpress printing original plate consisting of such a composition alone or of this layer and a support is obtained by closely adhering a negative film or a positive film having a transparent image portion to the photosensitive resin layer. When exposure is performed by irradiating actinic rays from above, only the exposed portion is insolubilized and cured. As the active light, a light source such as a high-pressure mercury lamp, an ultrahigh-pressure mercury lamp, a metal halide lamp, a xenon lamp, or a chemical lamp, usually centered on a wavelength of 300 to 450 nm, is used.

  Subsequently, a non-exposed portion is dissolved and removed with an appropriate solvent to obtain a relief printing having a clear image portion. For this purpose, a spray developing device, a brush developing device or the like is used.

  Hereinafter, the effects of the present invention will be demonstrated in more detail with reference to Examples and Comparative Examples. The number of parts in the following examples and comparative examples represents parts by mass. Ink entanglement, image reproducibility and bleed out were evaluated by the following methods.

"Evaluation of ink entanglement"
Ink entanglement was evaluated using a rotary printing press (manufactured by Sanjo Kikai Seisakusho, P-20), and ink was evaluated using ultraviolet curable ink (manufactured by T & K TOKA, UV161 Indigo S). Coated paper (Gloss PW8K, manufactured by Lintec Corporation) was used as the substrate. The printing speed was 30 m / min. Under the above conditions, printing was first performed at 1000 m, and a print sample was collected. Subsequently, 1000 m printing was performed, and a sample after printing a total of 2000 m was obtained. The halftone dots to be evaluated were 125, 150, and 175 LPI, and the ink entanglement was evaluated with halftone dots of 1, 5, 10, and 20%. “A” when there is no ink entanglement, “B” when ink entanglement occurs only at the end of the halftone dot, “C” when ink entanglement occurs near the end of the halftone dot, and ink entanglement occurs throughout the halftone dot. In this case, “D” was set.

"Evaluation of image reproducibility"
The image reproducibility was evaluated using the 175-line highlight minimum halftone dot (%) and the minimum fine line (μm).
The 175 line highlight minimum halftone dot (%) was determined using a Nikon universal projector to determine whether the negative film 175 line 1 to 5% halftone dot was retained. If the reproduced area was 90% or more, it was determined that the halftone dot was retained, and the minimum halftone dot (%) was displayed.
The minimum fine line (μm) was determined whether there was no twist (bend) in the thin line using a 20 × magnifier to determine whether a 30-100 μm wide thin line could be reproduced with a negative film. The smallest thin line width (μm) that reproduced the narrowest thin line in which the twist did not occur among the judged thin lines was displayed.

"Evaluation of silicone compound bleed-out"
The silicone compound bleed-out was evaluated by pressing a PET film having a smooth surface against the surface of the photosensitive resin relief plate after plate making, and evaluating the presence or absence of deposits on the PET film.

Example 1
(A) component ε-caprolactam 52.2 parts, (B) component N, N′-bisamino (3-aminopropyl) piperazine (hereinafter abbreviated as BAPP) 23.0 parts, (C) component 1, 3.7 parts of 3-bisaminomethylcyclohexane [hereinafter abbreviated as 1,3-BAC], (D) component amino-modified silicone compound (Shin-Etsu Chemical Co., Ltd., KF-8008, amino group equivalent 5,700 g / mol) ) 0.5 part, 20.6 parts of adipic acid as component (E), and 100 parts of water were added to the reactor, and after sufficient nitrogen substitution, the mixture was sealed and gradually heated to an internal pressure of 10 kg / cm. ^After reaching ² , the water in the reactor was gradually distilled out and returned to normal pressure in 1 hour, and then reacted at normal pressure for 0.5 hour. A polyamide having a maximum polymerization temperature of 210 ° C. and a specific viscosity of 1.84 was obtained.

  55.0 parts of the obtained polyamide, 7.7 parts of N-methyltoluenesulfonic acid amide, 0.03 part of 1,4-naphthoquinone, 50.0 parts of methanol, and 10 parts of water were added in a heating and melting kettle equipped with a stirrer. At 60 ° C. for 2 hours to completely dissolve the polymer, 30.1 parts of an acrylic acid adduct of trimethylolpropane triglycidyl ether, 3.1 parts of methacrylic acid, 0.1 part of hydroquinone monomethyl ether, 1.0 part of benzyl dimethyl ketal was added and stirred for 30 minutes. Next, the temperature was gradually raised, methanol and water were distilled off, and the mixture was concentrated until the temperature in the kettle reached 110 ° C. At this stage, a fluid and viscous photosensitive resin composition was obtained.

  Next, the adhesive film side of the support film obtained by coating the adhesive film on the polyester film with a thickness of 250 μm and the polyvinyl alcohol (AH-24, Nippon Synthetic Chemical Co., Ltd.) with a thickness of 2 μm on the polyester film with a thickness of 125 μm. The photosensitive resin composition was sandwiched between the coated film and the cover film coated with a protective film, and heated and pressed at 100 ° C. to obtain a printing original plate for letterpress printing having a total thickness of 1080 μm.

Next, a negative film having a halftone dot line of 175% -1% to 95% is vacuum-adhered as an image to the printing original plate for letterpress printing from which the cover film has been peeled off, and a 25 W / m ² chemical lamp is used from the surface of the photosensitive resin. It exposed from the distance of 5 cm in height. Next, development was performed using a brush type washer (120 μmφ nylon brush, JW-A2-PD type produced by JEOL Ltd.) with 25 ° C. tap water as a developer, and further dried at 60 ° C. for 10 minutes with warm air. Thereafter, exposure was performed for 5 minutes with a chemical lamp of 25 W / m ² to obtain the intended printing plate. The details and evaluation results of the water-soluble polymer compound are shown in Table 1.

(Example 2)
ε-Caprolactam 50.8 parts, BAPP 22.4 parts, 1,3-BAC 3.6 parts, amino-modified silicone compound (Shin-Etsu Chemical Co., Ltd., X-22-161B, amino group equivalent 1500 g / mol) 3.0 parts A target printing plate was obtained in the same manner as in Example 1 except that 20.2 parts of adipic acid was used. The details and evaluation results of the water-soluble polymer compound are shown in Table 1.

(Example 3)
ε-Caprolactam 49.6 parts, BAPP 21.9 parts, 1,3-BAC 3.5 parts, amino-modified silicone compound (Shin-Etsu Chemical Co., Ltd., X-22-161A, amino group equivalent 800 g / mol) 5.0 parts The target printing plate was obtained in the same manner as in Example 1 except that 20.0 parts of adipic acid was used. The details and evaluation results of the water-soluble polymer compound are shown in Table 1.

Example 4
ε-caprolactam 43.3 parts, BAPP 19.1 parts, 1,3-BAC 3.0 parts, amino-modified silicone compound (Shin-Etsu Chemical Co., Ltd., KF-8010, amino group equivalent 430 g / mol) 15.0 parts, adipine The target printing plate was obtained in the same manner as in Example 1 except that 19.6 parts of acid was used. The details and evaluation results of the water-soluble polymer compound are shown in Table 1.

(Example 5)
ε-caprolactam 44.3 parts, BAPP 19.5 parts, 1,3-BAC 3.1 parts, amino-modified silicone compound (Shin-Etsu Chemical Co., Ltd., PAM-E, amino group equivalent 130 g / mol) 10.0 parts, adipine A target printing plate was obtained in the same manner as in Example 1 except that 23.1 parts of acid were used. The details and evaluation results of the water-soluble polymer compound are shown in Table 1.

(Example 6)
ε-caprolactam 49.7 parts, BAPP 21.9 parts, 1,3-BAC 3.5 parts, amino-modified silicone compound (Shin-Etsu Chemical Co., Ltd., KF-8004, amino group equivalent 1500 g / mol) 5.0 parts, adipine The target printing plate was obtained in the same manner as in Example 1 except that 19.8 parts of acid was used. The details and evaluation results of the water-soluble polymer compound are shown in Table 1.

(Example 7)
ε-caprolactam 49.8 parts, BAPP 21.9 parts, 1,3-BAC 3.5 parts, amino-modified silicone compound (Shin-Etsu Chemical Co., Ltd., KF-864, amino group equivalent 3800 g / mol) 5.0 parts, adipine The target printing plate was obtained in the same manner as in Example 1 except that 19.8 parts of acid was used. The details and evaluation results of the water-soluble polymer compound are shown in Table 1.

(Example 8)
ε-Caprolactam 43.1 parts, Acrylonitrile was added to both ends of polyethylene glycol having a number average molecular weight of 400, and 29.8 parts of α, ω-diaminopolyoxyethylene obtained by hydrogen reduction of this, 1,3-BAC7 .7 parts, amino-modified silicone compound (Shin-Etsu Chemical Co., Ltd., X-22-161B, amino group equivalent 1500 g / mol) 3.0 parts and adipic acid 16.5 parts The desired printing plate was obtained. The details and evaluation results of the water-soluble polymer compound are shown in Table 1.

(Comparative Example 1)
The target printing was carried out in the same manner as in Example 1 except that 52.5 parts of ε-caprolactam, 23.1 parts of BAPP, 3.7 parts of 1,3-BAC, and no amino-modified silicone compound were added, and 20.7 parts of adipic acid were used. Got a version. The details and evaluation results of the water-soluble polymer compound are shown in Table 1.

(Comparative Example 2)
ε-caprolactam 49.5 parts, BAPP 23.1 parts, 1,3-BAC 3.7 parts, silicone compound (Shin-Etsu Chemical Co., Ltd., KF-96-100CS, amino unmodified) 3.0 parts, adipic acid 20. The target printing plate was obtained in the same manner as in Example 1 except that the amount was 7 parts. The details and evaluation results of the water-soluble polymer compound are shown in Table 1.

(Comparative Example 3)
ε-caprolactam 40.9 parts, BAPP 16.5 parts, 1,3-BAC 2.6 parts, amino-modified silicone compound (Shin-Etsu Chemical Co., Ltd., KF-8008, amino group equivalent 5700 g / mol), adipine The target printing plate was obtained in the same manner as in Example 1 except that 15.0 parts of acid was used. The details and evaluation results of the water-soluble polymer compound are shown in Table 1.

  As is clear from Table 1, the photosensitive resin compositions for letterpress printing (Examples 1 to 7) within the scope of the present invention are less likely to cause ink entanglement during printing while maintaining good image reproducibility. Evaluation results were obtained.

  According to the photosensitive resin composition for letterpress printing of the present invention, an ink entanglement preventing effect excellent in sustainability can be imparted to the printing plate. This makes it possible to perform high-quality printing stably for a long period of time, which greatly contributes to the industry.

That is, the present invention has the following configurations (1) to (5).
(1) A photosensitive resin composition for letterpress printing containing at least a water-soluble polymer compound, a photopolymerizable unsaturated compound, and a photopolymerization initiator as essential components, wherein the water-soluble polymer compound is (A A copolycondensate obtained by a polycondensation reaction of ω-amino acid or a lactam thereof, (B) a hydrophilic diamine, (C) a hydrophobic diamine, (D) an amino-modified silicone compound, and (E) a dicarboxylic acid. A photosensitive resin composition for letterpress printing.
(2) The photosensitive resin composition for letterpress printing according to (1), wherein the amino group equivalent of the (D) amino-modified silicone compound is in the range of 100 g / mol to 10,000 g / mol.
(3) (D) The amino-modified silicone compound is amino-modified at both ends, and the ratio of each component to the total amount of the components (A) to (E) is as follows: The photosensitive resin composition for letterpress printing according to (1) or (2).
(A) ω-amino acid or lactam thereof 40-60% by mass
(B) Hydrophilic diamine 15-30% by mass
(C) Hydrophobic diamine 2-8% by mass
(D) Amino-modified silicone compound 0.1-20% by mass
(E) Dicarboxylic acid 15-30 mass%
(4) ( B ) The hydrophilic diamine is at least one selected from the group consisting of N, N′-bis (3-aminopropyl) piperazine and N, N- bis (3-aminopropyl) methylamine. The photosensitive resin composition for letterpress printing according to any one of (1) to (3), wherein:
(5) A printing plate precursor for letterpress printing, comprising a photosensitive resin layer comprising the photosensitive resin composition for letterpress printing according to any one of (1) to (4).

Claims (5)

  A photosensitive resin composition for letterpress printing comprising at least a water-soluble polymer compound, a photopolymerizable unsaturated compound, and a photopolymerization initiator as essential components, wherein the water-soluble polymer compound is (A) ω- A copolycondensate obtained by a polycondensation reaction of an amino acid or a lactam thereof, (B) a hydrophilic diamine, (C) a hydrophobic diamine, (D) an amino-modified silicone compound, and (E) a dicarboxylic acid. A photosensitive resin composition for letterpress printing.   The photosensitive resin composition for letterpress printing according to claim 1, wherein the amino group equivalent of (D) the amino-modified silicone compound is in the range of 100 g / mol to 10,000 g / mol. (D) The amino-modified silicone compound is amino-modified at both ends, and the ratio of each component to the total amount of the components (A) to (E) is as follows: The photosensitive resin composition for letterpress printing of Claim 1 or Claim 2.
(A) ω-amino acid or lactam thereof 40-60% by mass
(B) Hydrophilic diamine 15-30% by mass
(C) Hydrophobic diamine 2-8% by mass
(D) Amino-modified silicone compound 0.1-20% by mass
(E) Dicarboxylic acid 15-30 mass%   (A) The hydrophilic diamine is at least one selected from the group consisting of N, N′-bis (3-aminopropyl) piperazine and N, N′-bis (3-aminopropyl) methylamine. The photosensitive resin composition for letterpress printing according to any one of claims 1 to 3.   A printing original plate for letterpress printing, comprising a photosensitive resin layer comprising the photosensitive resin composition for letterpress printing according to any one of claims 1 to 4.