JPH1090892A - Photosensitive resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve resistance to water-babe ink by using a small amt. of a diene polymer or oligomer contg. hydrophilic groups as a hydrophilic component. SOLUTION: This photosensitive resin compsn. contains a polymer and/or an oligomer having -COOM and/or -SO3 M (M is an amine, ammonium or an amino compd.) as at least a terminal group and a conjugated diene skeleton as a hydrophilic component. The hydrophilic polymer is preferably polybutadiene contg. amino groups, a nitrile-butadiene copolymer contg. amino groups, a styrene-butadiene copolymer contg. amino groups, polyisoprene contg. amino groups or polychloroprene contg. amino groups. The polymer preferably has an amino group at a terminal. Two or more kinds of such polymers may be used in combination. A polymer having carboxyl or sulfonic acid groups in a side chain may further be contained as a hydrophilic polymer.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a photosensitive resin composition which has rubber elasticity, is capable of being developed with water, and has excellent ink resistance and is useful for flexographic printing. The present invention relates to a photosensitive resin composition suitable for a printing plate that can be developed with a liquid and has high durability when printing with an aqueous ink.

[0002]

2. Description of the Related Art As a conventional photosensitive resin plate for flexographic printing, a plate developed with an organic solvent is known. However, these printing plates have problems in safety to human body and environment such as toxicity and flammability. Was. Therefore, a water-developable photosensitive resin composition has been proposed as an alternative. For example, a conjugated diene hydrocarbon and α, β-ethylenically unsaturated carboxylic acid or a salt thereof as essential components, a copolymer containing a monoolefinically unsaturated compound and a photopolymerizable unsaturated monomer, A method using a photosensitive resin composition containing a photosensitizer (JP-A-52-134655, JP-A-5-134655)
JP-A-3-10648, JP-A-61-22339), a conjugated diene-based hydrocarbon polymer or a copolymer of a conjugated diene-based hydrocarbon and a monoolefinic unsaturated compound, and a hydrophilic polymer compound. Photosensitive elastomer composition containing gaseous ethylenically unsaturated compound and photopolymerization initiator as essential components (see JP-A-60-212451), hydrophobic oligomer containing α, β-ethylenically unsaturated group And a photosensitive resin composition containing an elastomer water-swellable substance and a photopolymerization initiator as essential components (see JP-A-60-173055).

Further, for the purpose of improving the mechanical strength and rebound resilience of a printing plate, a photosensitive resin composition containing hard organic fine particles (see JP-A-63-8648),
For the purpose of imparting water developability, imparting aqueous ink resistance, and improving printability, a photosensitive resin composition containing fine particles of crosslinkable resin (JP-A-2-175702, JP-A-3-17572)
-228060, JP-A-4-293907, JP-A-4-293909, JP-A-4-294
353, JP-A-4-340968, JP-A-5-32743, JP-A-5-150451 and JP-A-5-204139), and two-phase printing for the purpose of improving the ink receptivity of a printing plate. A photosensitive resin composition having a structure, a diazo compound and a dichromate in a continuous phase, and a dispersed phase containing particles having a particle size of 10 μm or less (Japanese Patent Laid-Open No. 59-3).
No. 6731).

[0004] In the above composition, JP-A-52-134
655, JP-A-53-10648, JP-A-61-2
In Japanese Patent No. 2339, development with an aqueous developer, for example, an alkaline aqueous solution or an alkaline aqueous solution-organic solvent system is possible, but development with so-called domestic water having a pH of 5.0 to 9.0 is difficult, and the relief portion is There are problems such as insufficient ink resistance. In the above composition, JP-A-60-212451 and JP-A-60-1
According to JP-A-73055, a hydrophilic component must be contained in a continuous phase in order to enable aqueous development, and in that case, the content of the hydrophilic component is limited due to thermodynamic safety. It is necessary to increase the content. Also in this case, it is difficult to achieve both water developability and ink resistance of the relief portion. In JP-A-7-168358, water developability and ink resistance are both achieved by coexisting a hydrophobic component and a small amount of a hydrophilic component, but problems such as high plate hardness remain. .

[0005]

The photosensitive resin compositions described in the above inventions and the like are prepared by introducing a carboxyl group or an alkali metal salt thereof into a plate composition, thereby adding an aqueous alkali solution to which sodium carbonate or borax is added. Alternatively, development with neutral water became possible. However, these compositions increase the affinity of the hydrophilic component for water, so the printing plate after curing also has a high hydrophilicity, and when printing with an aqueous ink often used in flexographic printing, printing is performed. When the printing plate swells and softens due to water and performs a large amount of printing, the reproducibility and color tone of the fine part of the printed matter may change during printing, or the fine part of the printing plate may be missing However, the use of water-developable photosensitive resin plates has been hindered. In recent years,
There is an increasing demand for an assortment of plate materials for cardboard printing applications, high-grade process color printing applications, and the like. For example, plasticizers have been blended to reduce the hardness for cardboard printing applications, and attempts have been made to reduce the hardness. However, the blending of the plasticizer lowers the resistance to the water-based ink as described above, and causes a problem in color tone reproducibility. Furthermore, the compounding of the plasticizer is considered to be one factor that lowers the rubber elasticity.
There is a problem that clear image reproducibility cannot be obtained due to deformation.

[0006]

Means for Solving the Problems The inventors of the present invention have made intensive studies and studies to solve the above-mentioned problems, and have found that diene-based polymers or oligomers containing a small amount of a hydrophilic group are used as a hydrophilic component. As a result, the resistance to the water-based ink was improved, and further, the hardness of the printing plate could be reduced. That is, the present invention provides a photosensitive resin composition comprising (A) a hydrophobic component (B) a hydrophilic component, (C) a compound having a photoreactive group, and (D) a photopolymerization initiator. ) At least at the terminal
M groups and / or —SO ₃ M groups (where M is an amine,
Shows ammonium and amino compounds. A) a conjugated diene skeleton containing a polymer and / or oligomer.

In the present invention, the compound (A) forming the hydrophobic component is a reactant of an organic compound, and includes polymers, oligomers, fatty acids or derivatives thereof having a molecular weight of 500 or more, and the polymer is preferably glass. Polymers having a transition temperature of 5 ° C. or less, including those used as general-purpose elastomers. For example, 1,4-polybutadiene, 1,2-polybutadiene, acrylonitrile rubber, butadiene acrylonitrile rubber, chloroprene rubber, polyurethane rubber, butadiene styrene copolymer, styrene-butadiene-styrene block copolymer, styrene-isoprene-styrene block copolymer, polyamide resin, polyamide resin, Polymers that impart rubber elasticity to plates such as saturated polyester resin, butadiene- (meth) acrylic acid copolymer, butadiene- (meth) acrylic acid-acrylic ester copolymer, silicone rubber, polyoxypropylene glycol, polyoxytetramethylene glycol, etc. Or polymethyl (meth) acrylate, polyethyl (meth) acrylate, polyisopropyl (meth) acrylate, poly-n-
Acrylic resin such as butyl (meth) acrylate, polystyrene, polypropylene, polyethylene, chlorinated polyethylene, polyacrylonitrile, polyvinyl chloride, polyvinyl acetate and copolymers thereof, polyurethane resin, polyester resin, polyamide resin, epoxy resin, etc. Examples of such a plate include polymers that impart hardness and stability to the plate, and these may be used alone or in combination of two or more as necessary, but are not limited thereto. Further, the polymer may be modified as necessary to have reactivity, and it is also possible to modify the polymer so that it can react with a monomer or a cross-linking agent, or between polymers.

Next, the hydrophilic component (B) is mainly a hydrophilic polymer and / or oligomer (hereinafter referred to as a hydrophilic polymer), and is a compound having a hydrophilic group and soluble or dispersible or swellable in water. . As the hydrophilic polymer used in the present invention, at least the terminal -CO
OM group and / or -SO ₃ M group (wherein, M represents an amine, an ammonium, an amino compound.) A polymer and / or oligomer of a conjugated diene skeleton having, as the conjugated diene skeleton, polybutadiene, nitrile - butadiene copolymer , Styrene-butadiene copolymers, polyisoprene, and polychloroprene.

An amine represented by M, ammonium,
Examples of the amino compound include ethylamine, n-propylamine, n-butylamine, diethylamine, n-propylamine, n-butylamine, triethylamine,
n-tripropylamine, n-tributylamine, ethanolamine, diethanolamine, triethanolamine, morpholine, N, N-dimethylaminoethyl (meth) acrylate, N, N-diethylaminoethyl (meth) acrylate, ethylenediamine, hexamethylenediamine And amine compounds such as amino group-containing polybutadiene, amino group-containing nitrile-butadiene copolymer, amino group-containing styrene-butadiene copolymer, amino group-containing polyisoprene, and amino group-containing polychloroprene. Among them, amines and amino compounds are particularly preferable, and as the hydrophilic polymer, amino group-containing polybutadiene, amino group-containing nitrile-butadiene copolymer, amino group-containing styrene butadiene copolymer, amino group-containing polyisoprene, and amino group-containing Polychloroprene is desirable, and those having an amino group at the terminal are desirable. These may be used alone or in combination as necessary, but are not limited thereto.

In the present invention, a polymer having a carboxyl group or a sulfonic acid group in a side chain may be contained as the hydrophilic polymer together with the polymer, and is used to neutralize at least a part of the polymer. Examples of the compound include hydroxides of alkali metals such as lithium hydroxide, potassium hydroxide and sodium hydroxide; alkali metal carbonates such as lithium carbonate, potassium carbonate and sodium carbonate; and alkali metals such as potassium t-butoxide and sodium methoxide. Metal alkoxides, hydroxides of polyvalent metals such as calcium hydroxide, magnesium hydroxide, and aluminum hydroxide; metal compounds such as polyvalent metal alkoxides including aluminum isopropoxide; and the above-mentioned amines, ammonium, amino compounds and the like Is mentioned.

The molecular weight of the hydrophilic polymer in the present invention is preferably about 1,000 to 30,000,
000 to 20,000, especially 1000 to 6000 is desirable. Similarly, the hydrophilic component may be used alone or in combination of two or more as necessary. However, the present invention is not limited thereto, and the polymers may be modified as needed.

Next, as the compound (C) having a photoreactive group, a monomer and / or an oligomer having one radically polymerizable ethylene group in one molecule (hereinafter referred to as a radically polymerizable monomer) or a molecule in one molecule. A monomer and / or oligomer having two or more radically polymerizable ethylene groups (hereinafter, referred to as a crosslinking agent) is used. Examples of the radical polymerizable monomer include styrene, vinyl toluene, chlorostyrene, t-butylstyrene, α-methylstyrene, acrylonitrile, acrylic acid, methacrylic acid, methyl (meth) acrylate, ethyl (meth) acrylate, and n- Propyl (meth) acrylate, iso-propyl (meth) acrylate, n-butyl (meth) acrylate, iso-butyl (meth) acrylate, sec-butyl (meth) acrylate, t-
Butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, n-nonyl (meth) acrylate,
n-decyl (meth) acrylate, lauryl (meth) acrylate, n-tridecyl (meth) acrylate, stearyl (meth) acrylate, ethylene glycol mono (meth) acrylate, propylene glycol mono (meth) acrylate, diethylene glycol mono (meth) acrylate , Dipropylene glycol mono (meth) acrylate, polyethylene glycol mono (meth) acrylate, polypropylene glycol mono (meth) acrylate, polyethylene glycol monomethyl ether mono (meth) acrylate, polypropylene glycol monomethyl ether mono (meth) acrylate, polyethylene glycol mono Ethyl ether mono (meth) acrylate, polypropylene glycol monoethyl ether mono (meth A) acrylate, n-butoxyethyl (meth) acrylate, phenoxyethyl (meth) acrylate, 2-phenoxypropyl (meth) acrylate, cyclohexyl (meth) acrylate, tetrahydrofurfuryl (meth) acrylate, glycidyl (meth) acrylate, allyl ( (Meth) acrylate, benzyl (meth) acrylate, tribromophenyl (meth) acrylate, 2,3-dichloropropyl (meth) acrylate, 3-chloro-2-hydroxypropyl (meth) acrylate, N, N-diethylaminoethyl (meth) ) Acrylate, N, N-dimethylaminoethyl (meth) acrylate, Nt-butylaminoethyl (meth) acrylate, acrylamide, N, N-
Dimethylacrylamide, N, N-diethylacrylamide, and the like.

The crosslinking agents include ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate, propylene glycol di (meth) acrylate, dipropylene glycol di (meth) acrylate, Polypropylene glycol di (meth) acrylate, 1,3-butylene glycol di (meth) acrylate, trimethylolpropane tri (meth) acrylate, 1,4-butanediol di (meth) acrylate,
Neopentyl glycol di (meth) acrylate, 1,
6-hexanediol di (meth) acrylate 1,9-
Nonanediol di (meth) acrylate, 1,10-decanediol di (meth) acrylate, pentaerythritol di (meth) acrylate, pentaerythritol tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, glycerol di (meth) acrylate Glycerol allyloxydi (meth) acrylate, 1,1,1-trishydroxymethylethanedi (meth) acrylate, 1,1,1-trishydroxymethylethanetri (meth) acrylate, 1,1,1
-Trishydroxymethylpropane di (meth) acrylate, 1,1,1-trishydroxymethylpropane tri (meth) acrylate, triallyl cyanurate, triallyl isocyanurate, triallyl trimellitate, diallyl terephthalate, diallyl phthalate, divinyl Benzene, polyurethane (meth) acrylate,
Compounds having two or more radically polymerizable ethylene groups in one molecule, such as polyester (meth) acrylate, may be mentioned. In addition, ethylene group, epoxy group, isocyanate group, amino group, hydroxyl group in one molecule ,
Compounds having a plurality of reactive functional groups such as a carboxyl group may also be mentioned, and these may be used alone or in combination as necessary.

Next, (D) photopolymerization initiators include, for example, benzophenones, benzoins, acetophenones,
Examples include benzyls, benzoin alkyl ethers, benzyl alkyl ketals, anthraquinones, thioxanthones and the like. Specifically, benzophenone, chlorobenzophenone, benzoin, acetophenone, benzyl, benzoin methyl ether, benzoin isopropyl ether, benzoin isobutyl ether, benzyl methyl ketal, benzyl ethyl ketal, benzyl isopropyl ketal, anthraquinone, 2-chloroanthraquinone, thioxanthone, -Chlorothioxanthone and the like.

In the present invention, the blending amount of each of the above components is 10 to 90% by weight, preferably 40 to 80% by weight, particularly preferably 50 to 70% by weight of the hydrophobic component.
And the content of the hydrophilic component (B) is 5 to 30% by weight, preferably 5 to 20% by weight, and particularly preferably 5 to 15% by weight. In the (B) hydrophilic component, the —COOM group and / or —SO ₃ M group in the hydrophilic polymer is 1 as acid equivalent.
00 to 10000 mg / 10 ⁶ g, preferably 1000
-5000 mg / 10 ⁶ g, particularly preferably 1000-106 mg
It is preferred to contain 3000 mg / 10 ⁶ g. (C) the compound having a photoreactive group is 5 to 60% by weight,
It is preferably 15 to 40% by weight, particularly preferably 20 to 3% by weight.
0% by weight, and (D) the photopolymerization initiator is 0.1 to 10% by weight, preferably 0.5 to 5% by weight, particularly preferably 0.5 to 2% by weight.

In the present invention, a thermal polymerization inhibitor may be contained in addition to the above composition in order to simply prevent thermal polymerization without suppressing the photocrosslinking reaction. Useful thermal polymerization inhibitors include, for example, hydroquinone, hydroquinone monoethyl ether, catechol, pt-butylcatechol, 2,6-di-butyl-p-cresol and the like. Further, in the present invention, a liquid polybutadiene rubber, a liquid polyacrylonitrile butadiene rubber, a liquid rubber such as a liquid isoprene rubber, a polyvinyl chloride, a chlorinated polyethylene, etc. Low molecular weight elastomers can be included.

The phase structure of the photosensitive resin composition containing the above-mentioned components includes a structure in which a hydrophobic component is a particulate dispersed phase and a hydrophilic component surrounds the periphery thereof to form a continuous phase, and the hydrophobic component is a core component. The structure in which the core-shell particles in which the hydrophilic component has become a shell in which another hydrophobic component has become a continuous phase,
A structure in which the hydrophilic component becomes a particulate dispersed phase and the hydrophobic component becomes a continuous phase, a structure in which both the hydrophobic component and the hydrophilic component become entangled with each other in a continuous phase, and a structure in which the hydrophobic component and the hydrophilic component become hydrophilic. And a structure in which the active ingredients are uniformly compatible. In these structures, it is preferable that the hydrophilic component and the hydrophobic component that has become a continuous phase are not chemically crosslinked in an uncured state. On the other hand, the particulate hydrophobic component may or may not be crosslinked in an uncured state. Further, the hydrophobic component and the hydrophilic component may or may not be chemically bonded to each other.

The method for producing the photosensitive resin composition of the present invention is to obtain a particulate polymer by emulsion polymerization or suspension polymerization, or to use the components of the particulate dispersed phase obtained by pulverizing the polymer, alone or in combination. A method of mixing and molding with a kneader or extruder with the components of the continuous phase,
A method in which a hydrophobic component and a hydrophilic component are kneaded in a lump and kneaded with a kneader or an extruder to form a phase-separated / dispersed mixture, and the hydrophobic component and the hydrophilic component are kneaded in a kneader or an extruder in a lump and uniform. A well-known method such as a method of forming a solution compatible with the material is used. Further, the polymer of the hydrophilic component and the hydrophobic component may be polymerized in advance, or a monomer may be blended and polymerized in the process of producing the photosensitive resin composition. In particular, when a hydrophilic component is arranged around particles of a hydrophobic component, emulsion polymerization or the like is often used.

[0019]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, an example of an embodiment will be described as a preferred method for obtaining the composition of the present invention, but the present invention is not limited thereto. First, (B) an oligomer obtained by neutralizing a carboxyl group of an acrylonitrile-butadiene oligomer having a terminal carboxyl group with di-n-butylamine as a hydrophilic component, and (A) chlorinated polyethylene and butadiene rubber as a hydrophobic component, ) Using butadiene oligoacrylate as a compound having a photoreactive group, (D) benzyldimethyl ketal as a photopolymerization initiator, and dissolving and dispersing hydroquinone monomethyl ether and the like in a solvent, kneading using a heating kneader, and then kneading the solvent. By removing the above, the photosensitive resin composition of the present invention can be obtained. The obtained photosensitive resin composition is heat-pressed with a polyethylene terephthalate film and a film obtained by laminating a slip coat layer mainly composed of polyvinyl alcohol on the same polyester film. A printing original plate can be obtained by heating and pressing so as to be in contact with each other.

The composition of the present invention having the above constitution is
The desired photosensitive resin plate can be obtained by appropriately selecting the raw materials, the structure, the production method, and the like according to the required physical properties. For example, physical properties required for a printing plate include JI
It is desirable in terms of printing characteristics that the SA hardness is 30 to 80 degrees and the rebound resilience is 20% or more. The photosensitive resin composition of the present invention has rubber elasticity, is useful as a flexographic printing plate, and has excellent ink resistance, ink transferability and printing durability. In addition, the photosensitive resin composition used in the present invention is mainly useful as a flexographic printing plate, but can also be applied to a photoresist and a sandblast, and can be used as an elastomer which is cured by ultraviolet rays, such as an adhesive and a film. , Paints, etc. can also be used.

[0021]

EXAMPLES Hereinafter, the present invention will be described specifically with reference to examples, but the present invention is not limited to these examples. In the examples, “parts” means “parts by weight”. The hardness, rebound resilience, and durability against water-based ink of the printing plate of the present invention were measured by the following methods. Hardness: Measured at 20 ° C. by a spring-type hardness test (type A) according to JIS-K6301. Rebound resilience: A steel ball having a diameter of 10 m / m (weight: 4.16 g) was dropped from a height of 20 cm, and the height (a) of the rebound was read, which was expressed as (a / 20) × 100%. Durability against water-based ink: 2cm for convex part of relief
× 5 cm, and the weight (b) was measured while the lowermost polyester film was attached. This was immersed in water at 25 ° C., one day later, the attached water was wiped off, and the weight (c) was measured immediately. Was used as an index of durability for water-based ink. Formula 1 Water absorption (%) = (c−b) / b × 100

Example 1 A solution in which 100 parts of an acrylonitrile-butadiene oligomer having a terminal carboxyl group (Hycar CTBN1300 × 9 manufactured by Ube Industries, Ltd.) was dissolved in 150 parts of tetrahydrofuran was stirred at room temperature with 7 parts of di-n-butylamine. While stirring for 30 minutes to obtain a hydrophilic polymer [1]. 12 parts of the above hydrophilic polymer [1] and chlorinated polyethylene (Eraslen 301MA manufactured by Showa Denko KK) as a hydrophobic polymer 46
Part, butadiene rubber (BR 02LL, manufactured by Nippon Synthetic Rubber Co., Ltd.), 14 parts, butadiene oligoacrylate (B
27 parts of AC-45 manufactured by Osaka Organic Co., Ltd., 1 part of benzyldimethyl ketal (Irgacure 651 manufactured by Ciba Geigy) and 0.5 part of hydroquinone monomethyl ether were dissolved and dispersed in 67 parts of toluene and 6 parts of water. After kneading at 70 ° C. using a heating kneader and defoaming, the obtained photosensitive resin composition was heated at 100 ° C. with a heat press machine.
A pressure of 100 kg / cm ² was applied between a polyethylene terephthalate film having a thickness of 125 μm and a film in which 2 μm of polyvinyl alcohol was coated on one side of the same polyester film for 10 seconds so that the polyvinyl alcohol coat layer was in contact with the photosensitive resin. 1. Thickness
An 8 mm sheet (printing plate) was prepared.

Next, the uppermost polyester film is peeled off to leave a polyvinyl alcohol film on the photosensitive resin layer.
A negative film having an image is adhered thereon, and an illuminance of 25 W / m ² , 3 using a mercury lamp (manufactured by Dainippon Screen Co., Ltd.)
Exposure for one minute. After removing the negative film, the mixture was treated with a developer containing 2% by weight of sodium alkylnaphthalenesulfonate (Perex NB-L, manufactured by Kao Corporation) at 40 ° C and 15 ° C.
Minute development with a brush, the amount of scum generated in the development process was very small, and the relief depth was 1.0
mm image pattern was obtained. This image pattern faithfully reproduced the image of the negative film used. In addition, the obtained relief had good ink transferability and showed a clear image. Furthermore, the water absorption of the obtained relief was 1.0%, which suggested that the durability to the water-based ink was high. The absolute hardness of the obtained relief is 50 ° A.
Met.

Example 2 An original photosensitive resin plate was prepared in the same manner as in Example 1 except that 10 parts of tri-n-butylamine was used in place of 7 parts of di-n-butylamine in the hydrophilic polymer [1] of Example 1. As a result, the amount of scum generated in the developing step was very small, and an image pattern having a relief depth of 1.5 mm was obtained. In addition, the obtained relief had good ink transferability and showed a clear image. Further, the obtained relief had a water absorption of 1.1%, which suggested that the durability to the water-based ink was high. The absolute hardness of the obtained relief was 48 ° A.

Example 3 Photosensitivity was the same as in Example 1 except that 4 parts of N, N-dimethylaminoethyl methacrylate were used instead of 7 parts of di-n-butylamine in the hydrophilic polymer [1] of Example 1. When a conductive resin master was prepared and developed, the amount of scum generated in the developing step was very small, and an image pattern having a relief depth of 1.1 mm was obtained. In addition, the obtained relief had good ink transferability and showed a clear image. Furthermore, the water absorption of the obtained relief was 1.0%, which suggested that the durability to the water-based ink was high. The absolute hardness of the obtained relief was 53 ° A.

Example 4 In place of the hydrophilic polymer [1] of Example 1, 100 parts of an acrylonitrile-butadiene oligomer having a terminal carboxyl group and an acrylonitrile-butadiene oligomer having a terminal amino group (Hycar ATBN 1300 × 16)
A photosensitive resin master was prepared and developed in the same manner as in Example 1 except that 50 parts of a salt (manufactured by Ube Industries, Ltd.) were used. The amount of scum generated in the developing process was very small, and the relief depth was very small. A 1.0 mm image pattern was obtained. Also, the obtained relief has good ink transferability,
A clear image was shown. Further, the obtained relief had a water absorption of 1.3%, suggesting that the durability was high for water-based inks. The absolute hardness of the obtained relief is 52 ° A.
Met.

Example 5 A butadiene oligomer having a terminal carboxyl group (Hycar CT) was used in place of the hydrophilic polymer [1] of Example 1.
B2000 × 162 Ube Industries, Ltd.) 100 parts,
An acrylonitrile-butadiene oligomer having a terminal amino group (Hycar ATBN1300 × 16 manufactured by Ube Industries, Ltd.) was used except that a salt of 40 parts was used, and a photosensitive resin master was prepared and developed in the same manner as in Example 1. The amount of scum generated in the process was very small, and an image pattern having a relief depth of 2.0 mm was obtained. In addition, the obtained relief had good ink transferability and showed a clear image. Furthermore, the water absorption of the obtained relief is 0.8%
Indicated that the durability to water-based ink was high.
The absolute hardness of the obtained relief was 52 ° A.

COMPARATIVE EXAMPLE 1 The procedure of Example 1 was repeated except that 7 parts of di-n-butylamine were not added to the hydrophilic polymer [1] of Example 1.
When a photosensitive resin master was prepared and developed in the same manner as
The relief depth was 0.6 mm, which was not suitable for use as a printing plate.

Comparative Example 2 The procedure of Example 1 was repeated except that an aqueous solution in which 2 parts of sodium hydroxide were dissolved in 6 parts of ion-exchanged water was used instead of 7 parts of di-n-butylamine in the hydrophilic polymer [1] of Example 1. When a photosensitive resin original plate was prepared and developed in the same manner as in Example 1, the relief depth was 0.6 mm, which was not suitable for use as a printing plate.

Comparative Example 3 An original photosensitive resin plate was prepared in the same manner as in Comparative Example 2 except that 2 parts of magnesium hydroxide was used in place of 7 parts of di-n-butylamine in the hydrophilic polymer [1] of Example 1. ,
Upon development, the relief depth was 0.3 mm, which was not suitable for use as a printing plate.

Comparative Example 4 A butadiene oligomer having a terminal carboxyl group (Hycar CT) was used instead of the hydrophilic polymer [1] of Example 1.
A photosensitive resin master was prepared and developed in the same manner as in Example 1 except that B2000 × 162 (manufactured by Ube Industries, Ltd.) was used. The relief depth was 0.1 mm, which was suitable for use as a printing plate. Did not.

Comparative Example 5 In place of the hydrophilic polymer [1] of Example 1, a terminal amino group-containing acrylonitrile-butadiene oligomer (Hy
car ATBN1300 × 16 Ube Industries, Ltd.)
A photosensitive resin original plate was prepared and developed in the same manner as in Example 1 except for using, and the relief depth was 0.1 mm, which was not suitable for use as a printing plate.

Reference Example Table 1 shows the developing speed, hardness, rebound resilience and water absorption of the reliefs obtained in Examples 1 to 5 and Comparative Examples 1 to 5.

[0034]

[Table 1]

[0035]

As described above, the photosensitive resin composition of the present invention has improved aqueous developability (development speed, etc.) as compared with the conventionally known photosensitive resin composition, and surprisingly, It has the feature of high durability. Furthermore, it has excellent image reproducibility and high printing plate flexibility, so it can be used for a wide range of brands including cardboard printing and high-grade process color printing. Also,
The amount of scum generated due to aggregation of the resin flowing out into the developing solution is small, and troubles such as scum adhering to the developed printing plate and disturbing the image during printing can be suppressed. Furthermore, since this photosensitive resin plate can be developed in an aqueous system, a great advantage is that the waste liquid of the developer can be easily treated by a known waste liquid treatment technique such as pH adjustment, addition of an adsorbent or a flocculant, and microbial treatment. It is one of the major contributions to the industry.

Claims (1)

[Claims] (1) a hydrophobic component, (B) a hydrophilic component,
(C) in compound and (D) a photosensitive resin composition comprising a photopolymerization initiator having a photoreactive group, -COOM group at least at end as a hydrophilic component (B) and / or -SO ₃ M group (wherein , M is an amine, ammonium,
Shows an amino compound. A) a conjugated diene skeleton-containing polymer and / or oligomer.