JP2000010263A - Photosensitive resin composition and original plate for printing - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an original plate for printing having improved sensitivity, resolution and elasticity as a flexographic printing plate by incorporating a polyolefin and/or its deriv. into a photosensitive resin compsn. containing oligomers and/or polymers having conjugate diene chains. SOLUTION: This photosensitive resin compsn. containing oligomers and/or polymers having conjugate diene chains contains a polyolefin and/or its deriv. The oligomers and/or the polymers having conjugate diene chains may be incorporated in the form of hydrophobic or hydrophilic polymers or photopolymerizable ethylenic unsatd. compds. included as the structural component of the photosensitive resin compsn. The oligomers and/or the polymers having conjugate diene chains are polymers obtd. by polymerizing monomers essentially consisting of conjugate diene hydrocarbons or polymers obtd. by polymerizing monomers essentially consisting of conjugate diene hydrocarbons and monoolefin unsatd. compds.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a photosensitive resin composition containing an oligomer and / or a polymer having a conjugated diene chain, and more particularly to a photosensitive resin composition useful as a photosensitive resin composition for flexographic printing. The present invention relates to a printing original plate using the same.

[0002]

2. Description of the Related Art Hitherto, as a photosensitive resin composition for flexographic printing, a photosensitive resin composition having an oligomer and / or a polymer having a conjugated diene chain as a constituent material for exhibiting rubber elasticity has been known. Further, among these, those which can be developed with an aqueous developing solution for toxicity, flammability, human body and environmental safety have been proposed.

As such a photosensitive resin composition, for example, JP-A-52-134655 and JP-A-53-10
648, JP-A-61-22339, JP-A-60-221451, JP-A-60-173055
JP, JP-A-2-175702, JP-A-3-2
28060, JP-A-4-293907, JP-A-4-293909, JP-A-4-294353
JP, JP-A-4-340968, JP-A-5-3
No. 2,743, JP-A-5-150451, JP-A-5-204139, and the like.

[0004]

However, since the conventional photosensitive resin composition is not composed of a polymer whose main component is crosslinked before a photoreaction is performed by exposure, the viscosity of the photosensitive resin composition is small. Because of its softness, the photosensitive resin composition flows and deforms with the passage of time, so-called cold flow occurs. In addition, there is a problem that the printing original plate is deformed during handling before exposure.

Further, the oligomer or polymer having a conjugated diene chain, which is a main component of the photosensitive resin composition, is described in Journal of the Rubber Society of Japan, 32 (1959) P175, Rubb.
er Chem. Technol., 28 (1955) P746, Rubber
Chem. Technol., 41 (1968) P182, Ind. Eng. Ch.
As described in em. Prod. Res. Develop., 2 (1963) P273, Journal of the Rubber Society of Japan, 40 (1967) P881, etc., it is known that it is deteriorated by oxygen, peroxide, ozone, radical components and the like. Have been. For this reason, the photosensitive resin composition containing the oligomer and / or polymer having a conjugated diene chain is deteriorated by heat and light applied during the production of the photosensitive resin composition, the photosensitive resin composition and the original plate for photosensitive resin printing. Is easily deteriorated due to the above factors during storage, and the photosensitive resin composition and the printing original plate suffer from problems such as generation of cracks, reduction in rubber elasticity, and reduction in strength, and failing to maintain sufficient quality.

The present invention solves the problems of the above-mentioned conventional photosensitive resin composition containing an oligomer and / or polymer having a conjugated diene chain, improves the morphological stability of the photosensitive resin composition, and improves the cross-linkability. Flowing from the initial shape with the passage of time before the reaction and deforming, reducing the so-called cold flow, improving the handling workability and storage stability of the printing original plate containing the photosensitive resin composition, An object of the present invention is to provide a printing original plate having improved sensitivity, resolution, and elasticity as a flexographic printing plate.

[0007]

In order to achieve the above-mentioned object, the photosensitive resin composition of the present invention comprises a polyolefin and / or a polyolefin in a photosensitive resin composition containing an oligomer and / or a polymer having a conjugated diene chain. Or a derivative thereof.

[0008] The photosensitive resin composition having the above structure is
It has excellent morphological stability and can prevent so-called cold flow, which flows from its initial shape and deforms with the passage of time before the crosslinking reaction by light irradiation.

In this case, the polyolefin and / or
Or the derivative has a particle size of 10 nm to 10 μm,
The content can be from 0.001 to 10% by weight.

[0010] The printing original plate of the present invention is characterized in that a photosensitive layer comprising the above photosensitive resin composition is laminated on a support.

The printing plate having the above-mentioned structure is excellent in handling workability and shape stability during storage, and particularly excellent in sensitivity, resolution and elasticity when used as a flexographic printing plate.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the photosensitive resin composition and printing original plate of the present invention will be described.

The photosensitive resin composition of the present invention contains a polyolefin and / or a derivative thereof in a photosensitive resin composition containing an oligomer and / or a polymer having a conjugated diene chain.

In this case, the oligomer and / or polymer having a conjugated diene chain is contained in the form of a hydrophobic polymer, a hydrophilic polymer or a photopolymerizable ethylenically unsaturated compound contained as a constituent of the photosensitive resin composition. It is useful as a photosensitive resin printing plate having rubber elasticity.

In the above, the oligomer and / or polymer having a conjugated diene chain used in the present invention is generally an oligomer and / or polymer having a conjugated diene chain having a molecular weight of 500 or more. May be a polymer obtained by polymerizing a monomer containing a hydrocarbon as a main component, or a polymer obtained by polymerizing a monomer containing a conjugated diene-based hydrocarbon and a monoolefin-based unsaturated compound as a main component. it can. And when the polymer is a random copolymer or a block copolymer, the conjugated diene chain is an oligomer, which may be copolymerized to the main chain or a side chain as a part of the polymer. .
Further, the content is 1% by weight of the solid content in the photosensitive resin composition including those used as a hydrophilic polymer, a hydrophobic polymer or a photopolymerizable ethylenically unsaturated compound.
It is preferably from 0 to 70% by weight.

Specific examples of the conjugated diene hydrocarbon include, for example, 1,3-butadiene, isoprene,
Chloroprene and the like. These compounds alone,
Alternatively, two or more kinds are used in combination.

Specific examples of the above-mentioned monoolefinically unsaturated compound include, for example, styrene, α-methylstyrene, o-methylstyrene, m-methylstyrene and p-methylstyrene.
-Methylstyrene, acrylonitrile, methacrylonitrile, vinyl chloride, vinylidene chloride, acrylamide, methacrylamide, vinyl acetate, acrylate, methacrylate and the like.

Further, a polymer obtained by polymerizing a monomer containing a conjugated diene-based hydrocarbon as a main component or a polymer obtained by polymerizing a conjugated diene-based hydrocarbon and a monomer containing a monoolefin-based unsaturated compound as a main component. As the obtained polymer,
Specifically, butadiene polymer, isoprene polymer, chloroprene polymer, styrene-butadiene copolymer, styrene-isoprene copolymer, styrene-chloroprene copolymer, acrylonitrile-butadiene copolymer, acrylonitrile-isoprene copolymer Coalesce, acrylonitrile-chloroprene copolymer, acrylate-butadiene copolymer, methacrylate-butadiene copolymer, acrylate-isoprene copolymer,
Methacrylate-isoprene copolymer, acrylate-chloroprene copolymer, methacrylate-chloroprene copolymer, acrylonitrile-
Butadiene-styrene copolymer, acrylonitrile-isoprene-styrene copolymer, acrylonitrile-chloroprene-styrene copolymer, styrene-butadiene-
Styrene block copolymers, styrene-isoprene-styrene block copolymers and the like can be mentioned.

The polyolefins and / or derivatives thereof used in the present invention include all polyolefins having a molecular weight of 300 or more and / or derivatives thereof, which do not have a three-dimensional structure by a covalent bond.

Specific examples of such a material include a polyolefin-based thermoplastic elastomer such as ethylene propylene rubber, a copolymer of ethylene propylene and ethylidene norbonene or a copolymer of ethylene propylene and dicyclopentadiene. Ethylene propylene unsaturated bond-containing terpolymer, butyl rubber, chlorinated butyl rubber, brominated butyl rubber, iodinated butyl rubber, etc.

In addition, specifically, polyolefin ionomers such as —CO ₂ M ₁ group, —SO ₃ M ₂ group, —CO
It is a polyolefin derivative containing an ionic group such as an NH ₂ group, a —NH ₂ group, a —OH group, and a —PO ₃ M group. These include, for example, olefins such as ethylene and propylene and the above-mentioned -CO ₂ M ₁ group, -SO ₃ M ₂ group, -CONH ₂ , -N
It is obtained by copolymerization with an unsaturated compound containing an ionic group such as H ₂ , —OH group, and —PO ₃ M ₃ group.

The above-mentioned M ₁ , M ₂ and M ₃ are each a hydrogen ion or a monovalent metal ion (eg, Li ⁺ , Na ⁺ , K ⁺
Etc.) divalent metal ions (eg, Ca ²⁺ , Mg
²⁺ ) or a trivalent metal ion (eg, Al ³⁺ or the like) or a substituted or unsubstituted ammonium ion.

In the polyolefin ionomer,
The ionic group may or may not be ionic cross-linked between the polymers. When ion-crosslinked, the polyolefin-based ionomer has a three-dimensional structure due to ion crosslinking.

Other specific examples include vinyl acetate copolymerized polyolefins. Such a compound is obtained, for example, by copolymerization of ethylene or propylene with vinyl acetate, and can also be obtained by saponifying a part or all of the ester group containing the obtained compound, if necessary.

Other specific examples include low-density polyolefins and low-molecular-weight polyolefins.

The polyolefin and / or derivative thereof in the present invention may be used alone or in combination of two or more kinds. When two or more kinds are used in combination, the mixing ratio may be arbitrary.

Since the polyolefin and / or derivative thereof in the present invention is essentially incompatible with the oligomer or polymer having a conjugated diene chain, the polyolefin and / or the derivative thereof are so-called as described in a polymer blend (CMC Co., 1981). Microphase separation occurs, and the oligomer and / or polymer having a conjugated diene chain as a main component is present independently, and the polyolefin and / or its derivative is usually dispersed in the form of fine particles having a particle size of about 10 nm to 10 μm. ing. These dispersed polyolefins and / or derivatives thereof prevent cold flow of the photosensitive resin composition before photopolymerization as a filler and exhibit a function as a reinforcing agent.

In the present invention, the content of the polyolefin and / or the derivative thereof is usually 0.1 to 0.5 in the photosensitive resin composition.
It is preferably 001 to 10% by weight, more preferably 0.01 to 7% by weight.

In the present invention, it has been found that when the content of the polyolefin and / or its derivative is within the above range, high sensitivity is maintained without impairing the transmission of light in the photosensitive wavelength region.

When the content of the polyolefin and / or its derivative in the present invention is more than the above-mentioned content, the light transmittance is lowered and the sensitivity is lowered, or the composition is plasticized and the cold flow is accelerated. In addition, handling workability, storage stability, and form stability are not good, which is not preferable.

The photosensitive resin composition of the present invention contains a photopolymerizable ethylenically unsaturated compound. Examples of the photopolymerizable ethylenically unsaturated compound include an ethylenically unsaturated compound having a conjugated diene chain and an ethylenically unsaturated compound not containing a conjugated diene chain. The amount of the photopolymerizable ethylenically unsaturated compound is generally about 1 to 60% by weight, preferably about 2 to 50% by weight, based on the weight of the solid content of the photosensitive resin composition. Hereinafter, each will be described.

Examples of the photopolymerizable ethylenically unsaturated compound having a conjugated diene chain used in the present invention include unsaturated esters of polyols having a conjugated diene chain in a main chain and / or a side chain. As such,
For example, polybutadiene polyol (di) (meth) (urethane) acrylate, polyacrylonitrile butadiene polyol (di) (meth) (urethane) acrylate,
Polyisoprene polyol (di) (meth) (urethane)
Acrylates and polyconjugated diene-based polyols (di) (meth) (urethane) acrylates, such as polystyrene butadiene polyol (di) (meth) (urethane) acrylate, and the like can be given. These include, but are not limited to, those in which a part of the conjugated diene chain is reduced, maleic esters of the above polyols, and the like. These compounds can be used alone or in combination of two or more.

As the photopolymerizable ethylenically unsaturated compound containing no conjugated diene chain used in the present invention, an unsaturated ester is introduced into an alcohol having a structure in which neither a main chain nor a side chain has a conjugated diene chain. Things. Examples of such a compound include unsaturated esters of aliphatic alcohols such as cetyl alcohol and stearyl alcohol. Other examples include unsaturated esters of polyols. For example, ethylene glycol (di) (meta)
Acrylate, diethylene glycol (di) (meth) acrylate, glycerol (di) (meth) acrylate, 1,3-propanediol (di) (meth) acrylate, 1,4-butanediol (di) (meth) acrylate, 2,4-butanetriol (di) (meth) acrylate, 1,2,4-butanetriol (tri)
(Meth) acrylate, 1,4-cyclohexanediol (di) (meth) acrylate, 1,6-cyclohexanediol (di) (meth) acrylate, trimethylolpropane (di) (meth) acrylate, diallyl phthalate, trimethylolpropane (Tri) (meth) acrylate, diallyl phthalate, diethyl fumarate, dibutyl maleate, 1,9-nonanediol (di) (meth) acrylate, N-substituted maleamide compound (for example,
N-methylmaleamide, N-ethylmaleamide, N-laurylmaleamide, etc.), furthermore, polyethylene glycol (di) (meth) (urethane) acrylate, polypropylene glycol (di) (meth) (urethane) acrylate, poly Tetramethylene glycol (di) (meta)
Polyester polyols such as (urethane) acrylates (di) (meth) (urethane) acrylates; polyester polyols obtained by the condensation reaction of polyols such as polyethylene glycol and polycarboxylic acids such as terephthalic acid and adipic acid with unsaturated esters Polyester polyol (di) (meth) (urethane) acrylate, polyethylene polyol (di) (meth) (urethane) acrylate, polypropylene polyol (di)
Polyolefin polyols (di) (meth) (urethane) acrylates such as (meth) (urethane) acrylate and polyethylene propylene polyol (di) (meth) (urethane) acrylate; and maleic esters of the above-mentioned high molecular weight polyols. , But is not limited to this. These compounds can be used alone or in combination of two or more.

The above-mentioned methods for introducing an unsaturated ester into a polyol include a direct esterification reaction by a dehydration reaction between a polyol and an unsaturated carboxylic acid, and a transesterification reaction by a dealcoholation reaction between a polyol and an unsaturated carboxylic acid ester. General esterification method. Of these reactions, in the direct esterification reaction by the dehydration reaction between the polyol and the unsaturated carboxylic acid, a dehydration reaction between the polymerized polyol and the unsaturated carboxylic acid generated by the dehydration reaction between the polyols is performed in advance. Methods for obtaining ethylenically unsaturated compounds are also included.

The photopolymerization initiator used in the present invention includes benzophenones, benzoins, acetophenones, benzyls, benzoin alkyl ethers, benzylalkyl ketals, anthraquinones, thioxanthones, and the like. , Benzophenone,
Chlorobenzophenone, benzoin, acetophenone,
Benzyl benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin isobutyl ether, benzyl dimethyl ketal, benzyl diethyl ketal, benzyl diisopropyl ketal, anthraquinone, 2-chloroanthraquinone,
-Ethylanthraquinone, thioxanthone, 2-chlorothioxanthone, methylnaphthoquinone and the like are exemplified, and among them, benzyldimethylketal, methylnaphthoquinone and 2-ethylanthraquinone are preferable.

The photopolymerization initiator is preferably used in an amount of 0.01 to 10 based on the weight of the solid content of the photosensitive resin composition.
% By weight, more preferably 0.1 to 5% by weight. If the amount is less than 0.01% by weight, the photopolymerization initiating ability tends to be insufficient. If the amount exceeds 10% by weight, the interior of the photosensitive resin layer is not cured due to its own light shielding, and the image tends to be chipped by development. is there.

The photosensitive resin composition of the present invention is used as a printing master obtained by laminating a photosensitive layer on a support, and is subjected to a photoreaction with a negative film having an image and a photoreaction through a developing step by a developing solution or peeling. An image can be obtained by utilizing a difference in solubility in a developer before and after or a change in viscosity.

The developer used as the developer may be any of commonly used organic solvents such as hexane, heptane, orange oil, olive oil, gasoline, kerosene, toluene, xylene and other hydrocarbon solvents, tetrahydrofuran, dioxane and ethyl ether. Ether solvents such as ethyl acetate, ester solvents such as ethyl propyl acetate, methyl ethyl ketone, methyl butyl ketone, ketone organic solvents such as acetone, ethyl cellosolve, cellosolve organic solvents such as butyl cellosolve, Examples include alcohol-based organic solvents such as methanol, ethanol, isopropanol, propanol, and butanol, and halogen-based organic solvents such as trichloroethane, trichloroethylene, and chloroform. Door can be.

Further, from the viewpoints of stability to the working environment, protection of human health, and protection of the global environment, it is also possible to use an aqueous developer which is easily available as a developer.

When development is carried out with an aqueous developer, a hydrophilic polymer can be selected as the composition of the photosensitive resin composition of the present invention.

The hydrophilic polymer used in the present invention is:
It is a polymer soluble or swellable in water or a developer containing water as a main component. Examples of such a hydrophilic polymer include a —COOM group, a —SO ₃ M group,
-CONH ₂ group, -NH ₂ group, -OH group, and a polymer having a hydrophilic group such as -PO ₃ M group, crosslinked polymers and uncrosslinked linear polymer also contained.

M is a hydrogen ion, a monovalent metal ion (eg, Li ⁺ , Na ⁺ , K ^+, etc.), a divalent metal ion (eg, Ca ²⁺ , Mg ^2+, etc.), trivalent (Eg, Al ³⁺ ) or a substituted or unsubstituted ammonium ion.

Specifically, polyvinyl alcohol (PV
A), a general-purpose resin such as carboxymethyl cellulose, a diene rubber obtained by copolymerizing (meth) acrylic acid and a diene compound, a liquid polybutadiene modified with maleic anhydride, a liquid polyacrylonitrile, and a vinyl resin having butadiene and a phosphate group. Diene rubbers obtained by reacting monomers, or diene rubbers obtained by reacting butadiene with a vinyl compound having a phosphoric acid group and other vinyl compounds are mentioned.
It is preferable to use a hydrophilic polymer having 00 equivalents / 10 ⁶ g. If the amount of these groups is less than 50 equivalents / 10 ⁶ g, the affinity for water is poor, and it may be difficult to develop with neutral water. Conversely, 50,000 equivalents / 10 ⁶ g.
If it exceeds, the ink resistance may be poor.

Typical polymers having a -COOM group include polyurethane having a -COOM group, -COO
Polyurea urethane having an M group, polyester having a -COOM group, epoxy compound having a -COOM group, polyamic acid having a -COOM group, acrylonitrile-butadiene copolymer having a -COOM group,-
A styrene-butadiene copolymer having COOM groups,
Polybutadiene having a -COOM group, polyisoprene having a -COOM group, polychloroprene having a -COOM group, polyolefin having a -COOM group, sodium polyacrylate, polyacrylamide, polyvinyl alcohol (PVA), carboxymethyl cellulose (CMC), Hydroxyethyl cellulose (HEC),
And their derivatives, but are not limited thereto.

The above -COOM group is in the form of an acid or a salt. The polymer in which the -COOM group is in the form of a salt is -C
It is obtained by neutralizing a polymer having OOH groups. Compounds used for neutralization 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; potassium-t Alkoxides of alkali metals such as butoxide and sodium methoxide; hydroxides of polyvalent metals such as calcium hydroxide, magnesium hydroxide and aluminum hydroxide; polyvalent metal alkoxides such as aluminum isopropoxide; triethylamine, tri-n Tertiary amines such as -propylamine; secondary amines such as diethylamine, di-n-propylamine; cyclic amines such as morpholine;
Amino group-containing (meth) acrylates such as N, N-diethylaminoethyl (meth) acrylate; ammonium salts such as ammonium carbonate; metal acetate salts such as magnesium acetate, calcium acetate, and aluminum acetate. These can be used alone or in combination of two or more.

The above hydrophilic polymer may further have a polyoxyalkylene moiety as a hydrophilic group.
Further, it may have an ethylenically unsaturated group at a molecular terminal or a molecular inner chain so as to act as a crosslinking agent.

The hydrophilic polymer is a hydrophobic polymer 100
The amount is preferably 3 to 100 parts by weight, more preferably 10 to 70 parts by weight with respect to parts by weight. If the amount is less than 3 parts by weight, the water developability of a photosensitive resin printing plate prepared from the resulting photosensitive resin composition may be insufficient. In some cases, the water resistance of the printing plate of the non-conductive resin becomes insufficient, which is not preferable.

As an aqueous developer for developing the photosensitive resin composition containing the above-mentioned hydrophilic polymer, a surfactant may be added in addition to pure water and tap water.

As the above-mentioned surfactant, an anionic surfactant, a cationic surfactant, a nonionic surfactant, an amphoteric surfactant and the like can be widely used.
The addition amount of the surfactant is preferably 0.01 to 10% by weight in the developer. Further, a plurality of the above surfactants may be used in combination so as to perform optimal development.

The developer is preferably an aqueous developer in consideration of the safety of workers and the environment. If necessary, a water-based developer such as ethanol, isopropanol, cellosolve, glycerin, polyethylene glycol, dimethylformamide, dimethylacetamide, or acetone may be used. May be mixed with an organic solvent which can be mixed.

In the developing solution, neutral carbonates, sodium tripolyphosphate, potassium pyrophosphate, sodium silicate, sodium sulfate, sodium borate, sodium acetate, magnesium acetate, sodium citrate, sodium succinate, etc. Acidic or alkaline inorganic or organic salts; polymeric additives such as carboxymethylcellulose and methylcellulose;
Acids such as sulfuric acid, hydrochloric acid and phosphoric acid for adjusting H, alkalis such as sodium hydroxide, potassium hydroxide and calcium hydroxide; and other additives such as viscosity modifiers, dispersion stabilizers, flocculants and zeolides. You may add as needed.

For development, the photosensitive resin printing plate is immersed in a developer, and if necessary, the photosensitive resin layer is rubbed with a brush.
This is performed by removing uncured portions. The temperature during development is not particularly limited, but is preferably from 20 to 50C.

The photosensitive resin composition of the present invention can contain an elastomer containing no ethylenically unsaturated group in order to exhibit high elasticity, high resolution and high sensitivity.

Examples of the hydrophobic polymer used in the present invention include hydrophobic polymers used as general-purpose elastomers, and specifically include non-conjugated diene-based elastomers and conjugated diene-based elastomers.

Examples of the non-conjugated diene-based elastomer include a polyolefin-based elastomer having a chlorine atom and a polyolefin-based elastomer having no chlorine atom, and any of these is preferably used. Examples of the polyolefin elastomer having a chlorine atom include an elastomer obtained by chlorinating a polyolefin elastomer; an elastomer obtained by polymerizing a monomer having a chlorine atom; a monomer having a chlorine atom and having a chlorine atom. Elastomer obtained by copolymerization with a non-monomer, or an elastomer obtained by reacting chlorine or an active substance having a chlorine atom with a polymer having no chlorine atom. Specific examples of such a polyolefin-based elastomer having a chlorine atom include:
For example, chlorinated polyethylene (Eraslen manufactured by Showa Denko KK, Daisorac manufactured by Daiso, HOLT manufactured by Hoechst)
ALIZ, DOW-CPE manufactured by Dow Chemical Company, chlorinated ethylene-propylene rubber (Eraslen manufactured by Showa Denko KK), butyl chloride rubber, chlorinated polypropylene, vinyl chloride copolymer, polyvinylidene chloride, epichlorohydrin rubber, epichlorohydrid Copolymers of phosphorus and ethylene oxide, copolymers of epichlorohydrin and propylene oxide, copolymers of epichlorohydrin and allyl glycidyl ether (Epichromer manufactured by Daiso, HYDRIN manufactured by Goodrich, ZEON Corporation) Zeospan,
HERCLOR manufactured by Hercules, etc. are exemplified,
Among them, chlorinated polyethylene and chlorinated ethylene propylene rubber are preferred. These polymers are used alone or in combination of two or more.

The chlorine content of the above-mentioned polyolefin-based elastomer having a chlorine atom is preferably 5 to 60% by weight, more preferably 10 to 50% by weight. The photosensitive resin composition may be damaged or deteriorate in heat stability, and the photosensitive resin composition may be hardened or colored.

Examples of the polyolefin elastomer having no chlorine atom include ethylene-propylene rubber, isobutylene rubber, ethylene-propylene-butadiene terpolymer, acrylic rubber, ethylene-acryl rubber, ethylene-vinyl acetate copolymer, and butyl rubber. Butyl rubber, hydrogen reduced styrene-isoprene rubber, and the like. Considering the point of phase separation with an ethylenically unsaturated compound as described later, for example, the Mooney viscosity of ethylene-propylene rubber is ML.
_{1 + 4} (100 ° C.) is preferably 20 to 150.

In the present invention, a plasticizer other than those described above as a composition can be blended. Examples of the plasticizer used in the present invention include, for example, liquid polybutadiene rubber, liquid polyacrylonitrile butadiene rubber, liquid polystyrene butadiene rubber, liquid rubber such as liquid isoprene rubber, etc., dioctyl phthalate, aliphatic carbonized diphenyl phthalate and the like. Plasticizers such as phthalic acid ester of hydrogen, trimellitic acid ester such as trioctyl trimellitate, and adipic acid ester such as 2-ethylhexyl adipate, having a molecular weight of 400 to 300
Nearly zero plasticizers such as adipic acid-based polyesters or polyethers may be mentioned, and these may be used alone or in combination of two or more.

Since the photosensitive resin composition of the present invention contains at least an oligomer or / and polymer having a conjugated diene chain and an ethylenically unsaturated compound, it undergoes thermal polymerization, oxidative deterioration and ozone deterioration during production and storage. And other side reactions must be prevented without inhibiting photopolymerization.

For this purpose, hydroquinone, hydroquinone monomethyl ether, catechol, pt-butyl catechol, 2,6-di-t-butyl-p-cresol, which are generally used as thermal polymerization inhibitors and antioxidants, etc. Among them, it is preferable to add hadroquinone monomethyl ether and 2,6-di-t-butyl-p-cresol.

Other compounds that simultaneously suppress the oxidative deterioration and ozone deterioration and the thermal polymerization of the photopolymerizable ethylenically unsaturated compound include a compound having a phenol structure and a compound containing at least one of phosphorus, sulfur, nitrogen and boron. Having a phenol structure in the combination or at least in the molecule,
Further, a compound in which a compound containing at least one of phosphorus, sulfur, nitrogen, and boron is added to a site bonded to the phenol structure.

The compounds having a phenol structure include all compounds having a phenol skeleton, and typical compounds include phenol, o-cresol, 2,6-xylinol, 2,4,6-trimethyl Phenol, β-naphthol, ot-butylphenol, 2,6-di-t-butylphenol, 2,6-di-
t-butyl-4-methylphenol, 2,2′-methylenebis (4-methyl-6-t-butylphenol),
Elements of carbon, oxygen and hydrogen such as 4,4′-thiobis (3-methyl-6-t-butylphenol), hydroquinone, catechol, pt-butylcatechol, and 2,6-di-t-butyl-p-cresol And 2,4-bis- (n-octylthio) -6- (4-
Hydroxy-3,5-di-t-butylanilino) -1,
Examples include hetero compounds further containing nitrogen and sulfur, such as 3,5-triazine, and hetero compounds in which elements such as phosphorus and boron are bonded.

The compounds containing at least one of phosphorus, sulfur, nitrogen, and boron include triphenylphosphine, triphenylphosphite, trisnonylphenylphosphite, trilauryltrithiophosphite, trimethylphosphite, hexamethylphosphite, and hexamethylphosphite. Methylphosphamide, triphenylborate, 2,6-
Di-t-butyl-4-methylphenyldibutylborate, zinc dibutyldithiocarbamate, distearyldibutyldicarbamate, 2-mercaptobendiimidazole, 2,4-bis- (n-octylthio) -6
-(4-hydroxy-3,5-di-t-butylanilino) -1,3,5-triazine and the like.

The compound having at least one phenol structure in the molecule and containing at least one of phosphorus, sulfur, nitrogen and boron at a site bonded to the phenol structure is defined as the compound having the phenol structure and the phosphorus having the phenol structure. , A compound containing at least one of sulfur, nitrogen and boron by a covalent bond, wherein 2,4-bis- (n-octylthio) -6- (4-hydroxy-
3,5-di-t-butylanilino) -1,3,5-triazine, 2,2-thio-diethylenebis [3- (3,5
-Di-t-butyl-4-hydroxyphenyl) propionate], 3,5-di-t-butyl-4-hydroxybenzylphosphonate-diethyl ester, tris-
(3,5-di-t-butyl-4-hydroxybenzyl)
-Isocyanurate, 2,4-bis (octylthiomethyl) -o-cresol and the like.

Such a stabilizer is preferably blended at a ratio of 0.01 to 10% by weight, more preferably 0.001 to 5% by weight, based on the weight of the solid content of the photosensitive resin composition.

Examples of the method for preparing the photosensitive resin composition of the present invention include a method of mixing or collectively mixing the above components in an arbitrary order, and a method of uniformly swelling and dispersing each component in an arbitrary solvent. After that, a method of removing the solvent may be mentioned.
The photosensitive resin composition thus obtained is usually formed into a desired shape.

The printing original plate of the present invention preferably comprises an adhesive layer, a photosensitive layer comprising the above-mentioned photosensitive resin composition, an anti-adhesion layer and a cover film on a support.
As a production method, a photosensitive resin composition is sandwiched between a support on which an adhesive layer is formed and a cover film on which an anti-adhesion layer is formed (with the adhesive layer and the anti-adhesion layer both on the inside). ), And heat-press bonding to produce a photosensitive resin plate. The anti-adhesion layer contains polyvinyl alcohol, polyacrylamide, cellulose, polyamide and the like. As the support, a polyester film, a polyethylene film, a polypropylene film, or the like is used, and a polyester film is preferably used.

When such a printing original plate is irradiated with ultraviolet rays, at least the photopolymerizable ethylenically unsaturated compound is polymerized and cured. The ultraviolet light applied during curing is 1
Those having a wavelength of 50 to 500 nm, particularly 300 to 450 nm are preferable. Examples of such ultraviolet light sources include low-pressure mercury lamps, high-pressure mercury lamps, carbon arc lamps, ultraviolet fluorescent lamps, chemical lamps, xenon lamps, and the like.
A zirconium lamp or the like is desirable.

[0069]

EXAMPLES The present invention will be described in detail with reference to the following examples, but the present invention is not limited to these examples. In the examples, parts mean parts by weight.

1. M of photopolymerizable ethylenically unsaturated compound
Measurement conditions of n and Mw / Mn Equipment used: GPC LC-4A manufactured by Shimadzu Corporation Sample used: 1 wt% THF solution Flow rate: 1 cc / min Column: Shodex KF-805L Measurement temperature: 20 ° C. UV wavelength: 220 nm

2. Measurement method of viscosity of photopolymerizable ethylenically unsaturated compound JIS by rotor type Brookfield viscometer
It measured at 20 degreeC according to -K-6726.

3. Shape stability Cylindrical detection terminal (detection terminal diameter: 10 mm, load 10 g
Weight) with a thickness gauge (DG-911 manufactured by Ono Sokki Co., Ltd.) for 60 seconds on the photosensitive layer side of the support (total thickness 2800 mm) on which the photosensitive layer made of the photosensitive resin composition is formed. The amount of change (amm) is read and (a / 280
0) × 100% was set as a display value.

4. Relief Depth With respect to the printing original plate, the difference in height between the image area and the non-image area after development was measured by OG-911 manufactured by ONO Measuring Instruments.

5. A hardness About the printing original plate, it measured at 20 degreeC by the spring type hardness test (A method) according to JIS-K-6301.

6. Rebound resilience For the printing master plate, drop a steel ball of a total of 10 mm (weight 4.16 g) from a height of 20 cm, read the rebound height (a), and read (a / 20) x 100% as the display value. did.

7. Water swelling ratio The photosensitive resin composition is 1 mm thick, 20 mm long and 50 m wide.
m, and exposed to light at a dose of 4000 mJ / cm ² . This sheet is dried at 60 ° C.
Drying was performed for 4 hours. This weight was weighed (a
(G)). This was immersed in ion exchanged water at 20 ° C. for 24 hours and weighed (b (g)). The water swelling ratio is (ba)
/ A × 100% was set as a display value.

8. Halftone dot formation (150 lines, 3%) The presence or absence of halftone dot formation was visually observed with an optical microscope having a magnification of 100 times.

9. Particle size The particle size was measured by the Coulter counter method.

"Photopolymerizable ethylenically unsaturated compound No.
Synthesis of No. 1) hydroxyl-terminated polybutadiene (poly-bu R45HT, manufactured by Idemitsu Petrochemical Co., Ltd., number average molecular weight 280)
0) and acrylic acid in the presence of 2,4-bis- (n-octylthio) -6- (4-hydroxy-3,5-di-t-butylanilino) -1,3,5-triazine The photopolymerizable ethylenically unsaturated compound No. 1 was obtained. Table 1 shows the obtained characteristics.

"Photopolymerizable ethylenically unsaturated compound No.
Synthesis of 2) hydroxyl-terminated polybutadiene (poly-bu R45HT, manufactured by Idemitsu Petrochemical Co., Ltd., number average molecular weight 280)
0) and methyl acrylate are subjected to a transesterification reaction to produce a photopolymerizable ethylenically unsaturated compound No. 0). 2 was obtained. Table 1 shows the obtained characteristics.

"Photopolymerizable ethylenically unsaturated compound No.
Synthesis of 3] Hydroxyl-terminated polyisoprene (manufactured by Idemitsu Petrochemical Co., Ltd .: PIP, number average molecular weight 2800) and acrylic acid
2,4-bis- (n-octylthio) -6- (4-hydroxy-3,5-di-t-butylanilino) -1,3,3
Dehydration reaction was carried out in the presence of 5-triazine, and the photopolymerizable ethylenically unsaturated compound No. 5 was obtained. 3 was obtained. Table 1 shows the obtained characteristics.

"Synthesis of hydrophilic polymer No. 1" 276 parts of hexamethylene diisocyanate, 145 parts of dimethylolpropionic acid, 175 parts of polyoxytetramethylene glycol (PTMG-850, manufactured by Yasushiya Chemical Co., Ltd.), hydroxyethyl 60 parts of methacrylate, acrylonitrile-butadiene oligomer having an amino group at a terminal (H
YCAR-ATBN1300 × 16: Ube Industries, Ltd.) 3
Forty-three parts were reacted to obtain a polymer. The number average molecular weight (Mn) of this polymer is 1500, and the number average molecular weight (Mn) is 1500.
n), and the ratio Mw / Mn to the weight average molecular weight (Mw) was 4.5. A half equivalent of lithium hydroxide and a half equivalent of magnesium acetate were neutralized with respect to the -COOH group in the polymer to obtain a hydrophilic polymer No. 1 was obtained.

"Synthesis of hydrophilic polymer No. 2" 98 parts of 2-ethylhexyl acrylate, 1 part of 1,4-butanediol diacrylate, 1 part of 1,4-butanediol diacrylate, 1 part of allyl methacrylate, n- Emulsion polymerization of 80 parts of butyl acrylate and 20 parts of methacrylic acid produces hydrophilic polymer No. 2 was obtained.

"Synthesis of hydrophilic polymer No. 3" 60 parts of butadiene, 15 parts of methyl acrylate, 10 parts of ethylene phosphate methacrylate styrene, 1 part of divinylbenzene
Of the hydrophilic polymer N by emulsion polymerization of
o. 3 was obtained.

(Examples 1 to 15) Oligomers and / or polymers having at least a conjugated diene chain, polyolefins and / or derivatives thereof, photopolymerizable ethylenically unsaturated compounds, hydrophilic polymers as required, other polymers and light After mixing and homogenizing a polymerization initiator (benzyldimethyl ketal is 1% by weight based on the total weight of the photosensitive resin composition), a 3 mm-thick sheet is formed on a support made of a polyester film (120 μm thick). An original plate for printing made of a conductive resin composition was obtained. Table 2 shows the properties of the obtained photosensitive resin printing plate precursor.

(Comparative Examples 1 to 15) As Comparative Examples 1 to 5,
In Examples 1 to 5, the numerical values of the shape stability in the case where the thermoplastic polymer polyolefin and / or its derivative were not added are shown in Table 3.

[0087]

[Table 1]

[0088]

[Table 2]

In the tables, the numbers in parentheses in each example indicate the amounts (parts by weight). (Note 1) Developer Examples 1-3, 6-15: 40% water containing 1% by weight of fatty acid soap Examples 4, 5: Trichloroethylene / isopropanol = 80/20 20 ° C. (Component 1) Containing conjugated diene chain Oligomer and / or polymer NBR: acrylonitrile butadiene rubber IR: isoprene rubber BR: butadiene rubber SIS: styrene isoprene styrene block polymer PIP: isoprene oligomer SBS: styrene butadiene styrene block polymer (Component 2) photopolymerizable ethylenically unsaturated compound No. 1: Photopolymerizable ethylenically unsaturated compound No. 1 synthesized in the text 1 No. 2: Photopolymerizable ethylenically unsaturated compound No. 2 synthesized in the text 2 No. 3: Photopolymerizable ethylenically unsaturated compound No. 3 synthesized in the text 3 STA: stearyl methacrylate 1.6HX: 1,6-hexanediol dimethacrylate TMPTA: trimethylolpropane trimethacrylate (Component 3) Organic fine particles made of a thermoplastic polymer having a particle diameter of 10 μm or less SA100: Mitsui Chemicals Chemipore SA100, particle size <1 μm, ionomer-based polyethylene S120: Chemipore S120, manufactured by Mitsui Chemicals, Inc., particle size <1 μm, ionomer-based polyethylene V100: Chemival V100, manufactured by Mitsui Chemicals, particle size 12 μm, vinyl acetate copolymer polyethylene M200: Mitsui Chemicals Chemi-Wall M200, particle size 6 μm, low-density polyethylene A100: Mitsui Chemicals Co., Ltd. Chemi-Wall A100, particle size 4 μm, ethylene fluorene rubber W100: Mitsui Chemicals Chemi-Wall W100, particle size 3 μm, low molecular weight polyethylene W400: Mitsui Gakusha made Kemiha ° Lumpur W400, particle size 4 [mu] m, low molecular weight phosphonium ° Riechiren (component 4) a hydrophilic polymer No. 1: hydrophilic polymer No. 1 synthesized in the text 1 No. 2: Hydrophilic polymer No. 2 synthesized in the text 2 No. 3: hydrophilic polymer No. 3 synthesized in the text 3 N1072: carboxyl group-containing nitrile butadiene rubber PVA: 95% saponified polyvinyl alcohol (component 5) additives, etc. CPE: chlorinated polyethylene Irg. 565: 2,4-bis- (n-octylthio) -6- (4- Human peroxy-3,5-di-t-butylanilino) -1,3,5-triazine EPDM: Ethylene propylene norbornadiene rubber AR: Acrylic rubber

[0090]

[Table 3]

[0091]

According to the photosensitive resin composition of the present invention, a polyolefin and / or a derivative thereof is contained in a photosensitive resin composition containing an oligomer and / or a polymer having a conjugated diene chain. It is excellent in morphological stability and can reduce so-called cold flow, which flows from its initial shape and deforms with the passage of time before the crosslinking reaction.

Further, according to the printing plate precursor of the present invention, the handleability and storage stability are excellent, and particularly, the sensitivity, resolution and elasticity of the flexographic printing plate precursor are excellent.

 ────────────────────────────────────────────────── ─── Continuing from the front page (72) Inventor Satoshi Imahashi 2-1-1 Katata, Otsu-shi, Shiga F-term in Toyobo Co., Ltd. Research Laboratory (Reference) 2H025 AA01 AA02 AB02 AD01 BC55 CB08 2H096 AA04 BA01 BA05 CA11 4J002 AC021 AC031 AC061 AC071 AC081 AC091 AC113 BB152 BB182 BB232 BB242 BF022 BG041 BG051 BN151 BP011 CF273 CH053 CK023 EE047 EE057 EH076 EV307 GF00 GP03

Claims (3)

[Claims] An oligomer having a conjugated diene chain and / or
Alternatively, a photosensitive resin composition comprising a polymer and a polyolefin and / or a derivative thereof in the photosensitive resin composition. 2. The polyolefin and / or its derivative have a particle size of 10 nm to 10 μm and a content of 0.00
The photosensitive resin composition according to claim 1, wherein the content is 1 to 10% by weight. 3. A printing original plate comprising a support and a photosensitive layer comprising the photosensitive resin composition according to claim 1.