JPH11305431A - Photosensitive resin composition and photosensitive resin printing plate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a photosensitive resin compsn. to provide a photosensitive resin printing plate having high plate strength and printing performance by incorporating a thermoplastic elastomer, an ester compd. of an ethylene type unsatd. alcohol and an acid having a cyclic part, and a photopolymn. initiator. SOLUTION: This compsn. contains (A) a thermoplastic elastomer, (B) an ester compd. of an ethylene type unsatd. alcohol and an acid having a cyclic part, and (C) a photopolymn. initiator. The ethylene type unsatd. alcohol is an alcohol having photopolymerizable carbon-carbon unsatd. bond, and for example, allylalcohol and hydroxyalkyl(meth)acrylate can be used. As for the acid having a cyclic part, cyclohexane carboxylic acid and phthalic acid can be used, and phthalic acid is preferable. The amt. of the component (B) is 1 to 100 pts.wt., preferably 5 to 80 pts.wt., especially 10 to 60 pts.wt., to 100 pts.wt. of the thermoplastic elastomer (A).

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 and a photosensitive resin plate using the same. More specifically, the present invention relates to a photosensitive resin plate having high plate strength and printing performance (particularly, flexographic printing plate) and a photosensitive resin composition for obtaining the same.

[0002]

2. Description of the Related Art Usually, a flexographic printing plate is prepared by bringing a negative or positive film into close contact with a photosensitive resin plate, exposing a portion of the photosensitive layer by irradiating with active light, and washing and removing the unexposed portion (development). ) To form a relief. The photosensitive layer lumber of the photosensitive resin plate used for such a flexographic printing plate has a narrow fine line or a halftone dot as a convex portion of a developed relief and a deep white hole depth as a concave portion (image reproducibility is low). Of course, the plate strength such as tensile strength and elongation, which are the major printing durability of the photosensitive resin plate, is required. Further, at the time of printing, it is required that the resin plate has a small thickness (dot gain) due to external pressure when the ink is transferred from the resin plate coated with the ink to paper or a film to be printed. As a photosensitive layer material, a photosensitive resin composition containing a thermoplastic elastomer and a photopolymerizable ethylenic monomer as essential components is known.
It is essential that the photopolymerizable ethylenic monomer used in this composition has high compatibility with the thermoplastic elastomer in order to make the photosensitive elastomer composition uniform. In consideration of these facts, a monomer having a main chain of a straight chain has been often used as a monomer of a photosensitive material to date. However, the photosensitive resin plates using these photosensitive elastomer compositions have low plate strength, so that the relief is compressed during printing and the dot gain is increased, which is not satisfactory.

[0003]

SUMMARY OF THE INVENTION An object of the present invention is to provide a photosensitive resin plate having high plate strength and printing performance, and a photosensitive resin composition for obtaining the same.

[0004]

Means for Solving the Problems The inventors of the present invention have made intensive studies to achieve this object, and as a result, by using a photosensitive elastomer composition containing a specific photopolymerizable ethylenic monomer. The inventors have found that the above-mentioned object can be achieved, and have finally completed the present invention. That is, the present invention provides a photosensitive composition comprising (A) a thermoplastic elastomer, (B) an ester compound of an ethylenically unsaturated alcohol and an acid having a cyclic site, and (C) a photopolymerization initiator. A photosensitive resin composition comprising a resin composition and (C) a photopolymerization initiator, and a photosensitive resin plate having at least a support and a layer of the photosensitive resin composition described above.

The ester compound of the ethylenically unsaturated alcohol and the acid having a cyclic portion, which is the component (B) in the present invention, is a compound in which an ethylenically unsaturated alcohol and an acid having a cyclic portion are ester-bonded. In addition, a polymerization reaction is caused by a photopolymerization initiator. Further, the cyclic portion in the present invention indicates an aromatic or alicyclic group. The ethylenically unsaturated alcohol is a photopolymerizable alcohol having a carbon-carbon unsaturated bond, and specifically, allyl alcohol, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, Hydroxyalkyl (meth) acrylates such as 2,3-dihydroxypropyl (meth) acrylate, polyethylene glycol mono (meth) acrylate having an addition number of EO of 2 to 98, and addition number of EO of 2
~ 98 methoxy polyethylene glycol mono (meth)
Phenoxy polyethylene glycol mono (meth) acrylate having an addition mole number of acrylate and EO of 2 to 98;
Examples thereof include mono (meth) acrylates of polyoxyethylene such as nonylphenol methoxymonoethoxylate acrylate, methoxyethyl acrylate, and ethoxydiethylene glycol acrylate in which the number of moles of added EO is 1 to 4.

Specific examples of the acid having a cyclic moiety include cyclohexanecarboxylic acid, methoxylated cyclohexanecarboxylic acid, EO-modified cyclohexanecarboxylic acid,
EO-modified methoxylated cyclohexanecarboxylic acid, PO-modified cyclohexanecarboxylic acid, PO-modified methoxylated cyclohexanecarboxylic acid, ECH-modified cyclohexanecarboxylic acid, cyclohexanecarboxylic acids such as ECH-modified methoxylated cyclohexanecarboxylic acid, phenylacetic acid,
Benzoic acid, methylbenzoic acid, chlorobenzoic acid, nitrobenzoic acid, hydroxybenzoic acid, aminobenzoic acid, methoxybenzoic acid, EO-modified phenylacetic acid, EO-modified benzoic acid, EO-modified methylbenzoic acid, EO-modified chlorobenzoic acid, EO Modified nitrobenzoic acid, EO-modified hydroxybenzoic acid, EO-modified aminobenzoic acid, EO-modified methoxybenzoic acid, PO-modified phenylacetic acid, PO-modified benzoic acid, PO
Modified methylbenzoic acid, PO-modified chlorobenzoic acid, PO-modified nitrobenzoic acid, PO-modified hydroxybenzoic acid, PO
Modified aminobenzoic acid, PO-modified methoxybenzoic acid ECH
Modified phenylacetic acid, ECH-modified benzoic acid, ECH-modified methylbenzoic acid, ECH-modified chlorobenzoic acid, ECH-modified nitrobenzoic acid, ECH-modified hydroxybenzoic acid, EC
Benzoic acids such as H-modified aminobenzoic acid and ECH-modified methoxybenzoic acid, and polycarboxylic acids include phthalic acid, isophthalic acid, terephthalic acid, chlorophthalic acid,
Hydroxyphthalic acid, EO-modified phthalic acid, EO-modified isophthalic acid, EO-modified terephthalic acid, EO-modified chlorophthalic acid, EO-modified hydroxyphthalic acid, PO-modified phthalic acid, PO-modified isophthalic acid, PO-modified terephthalic acid, P
O-modified chlorophthalic acid, PO-modified hydroxyphthalic acid E
And phthalic acids such as CH-modified phthalic acid, ECH-modified isophthalic acid, ECH-modified terephthalic acid, ECH-modified chlorophthalic acid, and ECH-modified hydroxyphthalic acid. Of these, phthalic acids are preferred in the present invention.

Specific examples of the ester compound of the ethylenically unsaturated alcohol (B) and the acid having a cyclic site include EO-modified cyclohexanecarboxylic acid (meth).
Acrylate, PO-modified cyclohexanecarboxylic acid (meth) acrylate, ECH-modified cyclohexanecarboxylic acid (meth) acrylate, EO-modified cyclohexanecarboxylic acid (meth) acrylate, PO-modified cyclohexanecarboxylic acid (meth) acrylate, EO, PO-modified cyclohexanecarboxylic acid ( (Meth) acrylate, EO-modified phthalic acid (meth) acrylate, ECH-modified phthalic acid (meth) acrylate, EO-modified phthalic acid (meth) acrylate, PO-modified phthalic acid (meth) acrylate, E
O, PO modified phthalic acid methacrylate and the like,
As polyvalent acids, EO-modified phthalic acid di (meth) acrylate, PO-modified phthalic acid di (meth) acrylate, ECH
Modified phthalic acid di (meth) acrylate, EO-modified phthalic acid di (meth) acrylate, PO-modified phthalic acid di (meth) acrylate, EO, PO-modified phthalic acid dimethacrylate, and the like. A combination of an ethylenically unsaturated alcohol and a polyacid among these ester compounds,
Particularly, ECH-modified phthalic acid diacrylate is preferred.

The component (B) is used in an amount of 1 to 100 parts by weight, preferably 5 to 80 parts by weight, more preferably 10 to 100 parts by weight, per 100 parts by weight of the thermoplastic elastomer (A) as one component of the photosensitive resin composition. ~ 60 parts by weight is desirable. If the amount is less than 1 part by weight, curing of the photosensitive composition by light becomes insufficient, and the plate strength of the resin plate is reduced. On the other hand, if it exceeds 100 parts by weight, the handleability and solvent resistance of the resin plate are undesirably reduced.

In the photosensitive resin composition of the present invention, if necessary, other ethylenically unsaturated compounds may be added in addition to the above-mentioned component (B). As the ethylenically unsaturated compound other than the component (B), a compound having one or more radically polymerizable ethylene groups in a molecule as described below can be used alone or in combination of two or more. Specifically, styrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, pt
tert-butylstyrene, 1,3-dimethylstyrene,
Vinyltoluene, chlorostyrene, vinylnaphthalene,
Divinylbenzene, aromatic vinyl monomers such as trivinylbenzene, acrylonitrile, ethylenically unsaturated nitrile monomers such as methacrylonitrile, methyl acrylate,
Ethyl acrylate, propyl acrylate, n-acrylate
-Amyl, isoamyl acrylate, hexyl acrylate, ethylhexyl acrylate, octyl acrylate,
Glycidyl acrylate, methyl methacrylate, propyl methacrylate, n-amyl methacrylate, isoamyl methacrylate, hexyl methacrylate, ethyl hexyl methacrylate, octyl methacrylate, hydroxyethyl acrylate, hydroxypropyl acrylate, hydroxyethyl methacrylate, hydroxyethyl methacrylate Ethylenic unsaturated carboxylic acid ester monomers such as hydroxypropyl, glycidyl methacrylate, methoxyethylene glycol (meth) acrylate, methoxypropylene glycol (meth) acrylate, diethyl maleate and dimethyl itaconate; and ethylenic such as allyl glycidyl ether Unsaturated glycidyl ether, ethylenically unsaturated monocarboxylic acids such as acrylic acid and methacrylic acid, maleic acid, fumaric acid, citracone , Ethylenically unsaturated polycarboxylic acids such as itaconic acid, partial esters of ethylenically unsaturated polycarboxylic acids such as monoethyl maleate and monomethyl itaconate, ethylene acrylate phosphate, trimethylene acrylate phosphate, propylene phosphate Acrylate, tetramethylene phosphate, (bis) ethylene acrylate, (bis) trimethylene acrylate, (bis) tetramethylene acrylate, diethylene glycol acrylate, triethylene glycol acrylate, phosphoric acid (bis) ) Phosphorus such as diethylene glycol acrylate, phosphoric acid (bis) triethylene glycol acrylate, phosphoric acid (bis) polyethylene glycol (meth) acrylate and methacrylate corresponding thereto Ester group-containing ethylenically unsaturated monomer, tribromophenyl (meth) acrylate and 2,3-dichloro propyl (meth)
Halogen-containing ethylenically unsaturated monomers such as acrylate, 3-chloro-2-hydroxypropyl (meth) acrylate, N, N-diethylaminoethyl (meth) acrylate, N, N-dimethylaminoethyl (meth) acrylate and N And amino- and amide-group-containing ethylenically unsaturated monomers such as -t-butylaminoethyl (meth) acrylate, acrylamide, N, N-dimethylacrylamide and N, N-dimethylacrylamide.

Also, 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, 1,4-butanediol di (meth) acrylate, neo Pentyl glycol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, 1,9-nonanediol di (meth) acrylate, 1,10-decanediol di (meth) acrylate, 1,12-dodecanediol Di (meth) acrylate, 1,14-tetradecanediol di (meth) acrylate, pentaerythritol di (meth) acrylate, pentaerythritol tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, Serol di (meth) acrylate, glycerol allyloxydi (meth) acrylate, trititrolethane di (meth) acrylate, trititrolethane tri (meth) acrylate, trititrolpropane di (meth) acrylate, trititrolpropane tri (meth) acrylate , Triallyl cyanurate, triallyl isocyanurate, triallyl trimellitate, diallyl terephthalate, divinylbenzene, polyurethane (meth) acrylate, polyester (meth) acrylate, oligobutadiene (meth)
Compounds having two or more radically polymerizable ethylene groups in one molecule such as acrylate, oligoisoprene (meth) acrylate, and oligopropylene (meth) acrylate are exemplified. Particularly preferred ethylenically unsaturated compounds include 1,6-hexanediol di (meth) acrylate, 1,9-nonanediol di (meth) acrylate, 1,10-decanediol di (meth) acrylate, 1,12- Dodecanediol di (meth) acrylate, 1,14-tetradecanediol di (meth) acrylate, trimethylolpropane tri (meth) acrylate, oligobutadiene (meth) acrylate, oligoisoprene (meth) acrylate, and the like.

The thermoplastic elastomer which is the component (A) of the photosensitive resin composition of the present invention is not particularly limited.
A homopolymer of a conjugated diene monomer, a random copolymer of a conjugated diene and a monoene monomer copolymerizable therewith, a polymer block of a conjugated diene monomer and a polymer block of a monoene monomer Block copolymer and the like. The conjugated diene monomers constituting the thermoplastic elastomer include 1,3-butadiene, isoprene, and 2,3-butadiene.
Dimethyl-1,3-butadiene, 1,3-pentadiene, 1,3-hexadiene, chloroprene and the like can be mentioned. Of these conjugated dienes, butadiene is preferred. Examples of the monoene monomer constituting the thermoplastic elastomer include styrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, p-tert-butylstyrene, 1,3-dimethylstyrene, vinyltoluene,
Aromatic vinyl monomers such as chlorostyrene, vinylnaphthalene, divinylbenzene, and trivinylbenzene; ethylenically unsaturated nitrile monomers such as acrylonitrile and methacrylonitrile; methyl acrylate, ethyl acrylate, propyl acrylate, and acrylic N-Amyl acrylate, isoamyl acrylate, hexyl acrylate, ethyl hexyl acrylate, octyl acrylate, glycidyl acrylate, methyl methacrylate, propyl methacrylate, n-amyl methacrylate, isoamyl methacrylate, hexyl methacrylate, ethylhexyl methacrylate Octyl methacrylate, hydroxyethyl acrylate, hydroxypropyl acrylate, hydroxyethyl methacrylate, hydroxypropyl methacrylate, glycidyl methacrylate, ethyl Glycol diacrylate, trimetholpropane triacrylate, 1,4-butanediol di (meth) acrylate, propylene glycol diacrylate, 1,6-hexanediol di (meth) acrylate, methoxyethylene glycol (meth) acrylate, methoxypropylene glycol Ethylenically unsaturated carboxylic acid ester monomers such as (meth) acrylate, diethyl maleate and dimethyl itaconate; ethylenically unsaturated glycidyl ethers such as allyl glycidyl ether; ethylenically unsaturated monocarboxylic acids such as acrylic acid and methacrylic acid Acid, maleic acid, fumaric acid,
Ethylenically unsaturated polycarboxylic acids such as citraconic acid and itaconic acid, and partially esterified ethylenically unsaturated polycarboxylic acids such as monoethyl maleate and monomethyl itaconate, ethylene phosphate, trimethylene acrylate, and phosphorus Acid propylene acrylate, phosphate tetramethylene acrylate, phosphoric acid (bis) ethylene acrylate, phosphoric acid (bis) trimethylene acrylate, phosphoric acid (bis) tetramethylene acrylate, diethylene glycol phosphate, triethylene glycol acrylate, phosphoric acid (Bis) diethylene glycol acrylate, phosphoric acid (bis) triethylene glycol acrylate, phosphoric acid (bis) polyethylene glycol (meth) acrylate, and the corresponding methacrylate And the like. Phosphoric acid ester group-containing ethylenically unsaturated monomers, such as tribromophenyl (meth) acrylate, 2,3-dichloropropyl (meth) acrylate, and halogen-containing, such as 3-chloro-2-hydroxypropyl (meth) acrylate. Ethylenically unsaturated monomers,
N, N-diethylaminoethyl (meth) acrylate, N, N-dimethylaminoethyl (meth) acrylate, Nt-butylaminoethyl (meth) acrylate, acrylamide, N, N-dimethylacrylamide, N, N
Examples include amino and amide group-containing ethylenically unsaturated monomers such as N-dimethylacrylamide. 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, 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,
1,12-dodecanediol di (meth) acrylate,
1,14-tetradecanediol di (meth) acrylate, pentaerythritol di (meth) acrylate, pentaerythritol tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, glycerol di (meth) acrylate, glycerol allyloxydi (meth) Acrylate, trititrolethanedi (meth) acrylate, trititrolethanetri (meth) acrylate, trititrolpropanedi (meth)
Acrylate, trititrolpropane tri (meth) acrylate, triallyl cyanurate, triallyl isocyanurate, triallyl trimellitate, diallyl terephthalate, divinylbenzene, polyurethane (meth) acrylate, polyester (meth) acrylate, oligobutadiene (meth) Compounds having two or more radically polymerizable ethylene groups in one molecule such as acrylate, oligoisoprene (meth) acrylate, and oligopropylene (meth) acrylate are exemplified. Among the monoene monomers, butadiene, styrene and acrylonitrile are preferred as monomers to be copolymerized with the conjugated diene monomer or as monomers constituting the monoene polymer block.

(A) Constituting the photosensitive resin composition of the present invention
Specific examples of the thermoplastic elastomer, polystyrene-polybutadiene-polystyrene type block copolymer,
Block copolymers such as polystyrene-polyisoprene-polystyrene type block copolymer, styrene-butadiene random copolymer, acrylonitrile-butadiene random copolymer, ethyl phosphate (meth) acrylate,
A random copolymer of a phosphate group-containing monoene monomer such as propylene phosphate (meth) acrylate and 1,3-butadiene, a phosphate group-containing monoene monomer, and 1,3-butadiene; And a hydrophilic group-containing random copolymer such as a random copolymer with an ethylenically unsaturated carboxylic acid alkyl ester. In addition to the above, thermoplastic elastomers such as epichlorohydrin rubber, chlorinated polyethylene, and silicone rubber may be used.

In order to apply the photosensitive resin composition of the present invention to obtain an aqueous development type photosensitive resin plate,
A thermoplastic elastomer, which is one component of the composition, is a mixture of a random copolymer or block copolymer having a hydrophilic group and a random copolymer or block copolymer having no hydrophilic group, preferably a hydrophilic copolymer. A mixture comprising a random copolymer having a group and a block copolymer having no hydrophilic group is used. Here, the hydrophilic group is -O
H group, -COOH group, -NH ₂ group, -COO- group, -S
An O ₃ — group, a —PO (OH) ₂ group, a —PO (OH) — group,
> A hydrophilic group such as a PO- group, preferably a carboxylic acid group such as a -COOH group. Those obtained by substituting these groups with metal ions are particularly preferable.

A random copolymer having a hydrophilic group or
As the block copolymer, a monoene monomer having a hydrophilic group is used.
Monomer and its copolymerizable monoene monomer or conjugate
Those obtained by copolymerization with a diene monomer are exemplified.
Specifically, polymerization of (meth) acrylic acid or its salts
Body, (meth) acrylic acid or its salts and alkyl (meth)
(T) copolymer with acrylate, (meth) acrylic acid or
Is a copolymer of its salts and styrene, (meth) acrylic
Copolymer of acid or its salts with vinyl acetate, (meth) a
Copolymerization of acrylic acid or its salts with acrylonitrile
Body, polyvinyl alcohol, carboxymethyl cellulose
Base, polyacrylamide, hydroxyethyl cellulose
, Polyethylene oxide, polyethylene imine,-
Polyurethane having COOM group, having -COOM group
Polyureurethane, Epoxy Having -COOM Group
Compound, polyamic acid having -COOM group and these
Or a derivative thereof. These hydrophilic polymers
-Can be used alone or in combination of two or more
Can be done. The above-mentioned polymer is the aforementioned ethylenically unsaturated polymer.
It may be modified as necessary so that it can react with the compound.
No. Here, M is a monovalent metal ion (eg, Li⁺, N
a⁺, K⁺, Rb⁺, Cs ⁺, Fr⁺Etc.) divalent metal
Ions (eg, Ca²⁺, Mg²⁺, Sr²⁺, Ba²⁺, Z
n²⁺, Cu²⁺, Ra²⁺Etc.) trivalent metal ions (eg
If Al³⁺, Fe³⁺Etc.) or substituted or unsubstituted ammonium
Um ion. Having the above -COOM group
Water-developable and water-resistant inks
From the viewpoint of achieving both properties, the -COOM group is 50 to 50,
It is preferably 000 equivalents / g. These -CO
A hydrophilic polymer having an OM group has a -COOH group
After producing a polymer, an alkali having M ions
(Eg, hydroxides, carbonates, acetates, alkoxides
Etc.) or by neutralizing with an amine compound
good.

The hydrophilic polymer is incorporated in the photosensitive resin composition in an amount of 1 to 50% by weight, preferably 5 to 30% by weight. When the amount of the hydrophilic polymer is less than 1% by weight, the developability of the obtained photosensitive resin plate in an aqueous developer decreases,
If it exceeds 50% by weight, the resulting photosensitive resin plate is not preferred because the water-resistant ink resistance of the resulting photosensitive resin plate is reduced.

The photopolymerization initiator, which is the component (C) of the photosensitive resin composition of the present invention, generates radicals upon irradiation with actinic light such as ultraviolet light, and causes a polymerization reaction of the ethylenically unsaturated monomer. To start. For example, benzophenones, benzoins, acetophenones, benzyls,
Examples include benzoin alkyl ethers, benzyl alkyl ketals, anthraquinones, thioxanthones, and the like. Specific examples include benzophenone, chlorobenzophenone, benzoin, acetophenone, benzyl, benzoin methyl ether, benzoin ethyl ether,
Benzoin propyl ether, benzoin butyl ether, benzyl dimethyl ketal, benzyl diethyl ketal, benzyl diisopropyl ketal, anthraquinone, 2-chloroanthraquinone, 1,4-naphthoquinone, thioxanthone, 2-chlorothioxanthone and the like.

The amount of the photopolymerization initiator (C) is from 0.1 to 10 parts by weight per 100 parts by weight of the thermoplastic elastomer (A).
Parts by weight, preferably 1 to 7 parts by weight. When the amount is less than 0.1 part by weight, the curing of the photosensitive composition by the active light becomes insufficient, and when the amount exceeds 10 parts by weight, the curing depth cannot be obtained due to its own shading, and the image after development hardly remains. It is not preferable. .

The photosensitive resin composition of the present invention may further comprise, if necessary, a plasticizer, a storage stabilizer and a photopolymerization initiator, in addition to the thermoplastic elastomer (A), the ester compound (B) and the photopolymerization initiator (C). , An ozone-resistant agent, and the like. Examples of the plasticizer include hydrocarbon oils such as naphthenic oil and paraffin oil, polystyrene having a molecular weight of 3000 or less, petroleum resin, polyacrylate, liquid 1,2-polybutadiene,
Examples thereof include 1,4-polybutadiene and terminal modified products thereof, liquid acrylonitrile-butadiene copolymer, liquid styrene-butadiene copolymer, and carboxylated products thereof. As storage stabilizers, hydroquinone, hydroquinone monomethyl ether, pyrogallol, p-
Phenols such as methoxyphenol, catechol, t-butylcatechol, 2,6-di-t-butyl-p-cresol and benzoquinone; quinones such as benzoquinone, p-toluquinone and p-xyloquinone; and amines such as phenyl-α-naphthylamine And the like.

The photosensitive resin composition of the present invention can be obtained by a usual method, for example, by kneading the above components using a kneader or a roll mill.

Next, the photosensitive resin plate of the present invention has a laminated structure comprising at least a support and a layer of the photosensitive resin composition formed on the main surface thereof. The support is usually made of a plastic film or sheet, and if necessary, has a release layer or an undercoat layer made of an adhesive or a primer. The support is not limited as long as it is commonly used in a flexographic printing plate, and may be a single-layered plastic film such as a polyethylene terephthalate film, a polypropylene film, or a polyimide film, a natural rubber, a synthetic rubber, or an elastic material such as a soft vinyl chloride resin. Examples include multilayer plastic films made of polyethylene terephthalate, polypropylene, polyimide, etc., on which the body composition is adhered.

In order to form a layer of the photosensitive resin composition on the main surface of the support, a conventionally known method may be employed. For example, after the photosensitive resin composition is formed into a sheet using a molding machine such as an extruder, a press, and a calendar, the sheet is adhered to a support or chloroform or carbon tetrachloride is used as the photosensitive resin composition. , Trichloroethane, methyl ethyl ketone, diethyl ketone, benzene, toluene, tetrahydrofuran or the like, and the components (A) to (C) dissolved therein are poured into a sheet frame, and then the solvent is evaporated to form a sheet. After molding, the sheet is glued to a support.

In the photosensitive resin plate of the present invention, a thin layer of a non-adhesive water-soluble polymer is preferably provided as a coating layer on the layer of the photosensitive resin composition. Since the surface of the photosensitive resin composition layer is usually highly adhesive, if an original image film is directly adhered to the surface, bubbles enter between the photosensitive resin composition and the film, causing irregular refraction of active light. As a result, the exposure and curing of the photosensitive layer do not proceed, and as a result, the reproducibility of the relief is deteriorated, and the original image film adhered to the surface of the photosensitive resin composition layer cannot be reused in some cases. By providing a thin layer of a non-tacky water-soluble polymer, the above problem is eliminated.

The photosensitive resin plate of the present invention may be further provided with a cover film. The cover film is made of a thermoplastic resin film. The cover film constitutes a protector film layer of the photosensitive resin composition layer, and in some cases also has a release layer. Examples of the cover film include a polyethylene terephthalate film, a polyethylene film, a polypropylene film, a polystyrene film and the like, and a plain film using these or a mat film having a surface roughness Ra of 0.01 to 2 μm by chemical etching is used. The thickness of the film is usually 50-200 μm, preferably 70-175 μm. If it is less than 50 μm, the film strength is insufficient, and the molded photosensitive resin plate is easily deformed. On the other hand, when the thickness exceeds 200 μm, the film strength is too strong, so that the photosensitive elastomer composition easily causes abnormal peeling from the sheet during cutting.

The photosensitive resin plate of the present invention can be developed in an aqueous system. For example, an uncured portion can be removed by a developer obtained by adding a surfactant to water. As the surfactant, anionic surfactants, cationic surfactants, nonionic surfactants, amphoteric surfactants, etc. can be used alone or in combination.
More than one kind can be used in combination. The developing solution includes sodium carbonate, sodium tripolyphosphate, potassium pyrophosphate, sodium silicate, sodium sulfate, sodium borate,
Acidic or alkaline inorganic or organic salts such as sodium acetate, magnesium acetate, sodium citrate and sodium succinate; polymeric additives such as carboxymethylcellulose and methylcellulose; acids such as sulfuric acid, hydrochloric acid and phosphoric acid for pH adjustment And various additives such as viscosity modifiers, dispersion stabilizers, flocculants and zeolites may be added as necessary. In the development, the photosensitive resin composition is immersed in a developer and, if necessary, rubbed with a brush to remove uncured portions.
The temperature of the developer is preferably 30 to 50C.

In the photosensitive resin plate of the present invention, a foam may be laminated on the surface of the support opposite to the surface on which the photosensitive resin composition layer is formed. The printing pressure at the time of flexographic printing can be adjusted by laminating foams.

[0026]

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 and comparative examples, parts and% are based on weight. The evaluation of the photosensitive resin composition and the photosensitive resin plate was performed based on the following test methods. <Evaluation of printability> For each of the compositions having a thickness of 3.0 mm, the matte film-formed polyethylene terephthalate film having the anti-adhesion layer was peeled off, and a negative film having an image was adhered thereon and the high pressure was applied. Exposure was performed with a mercury lamp (manufactured by Dainippon Screen) at an illuminance of 25 W / m ² for 5 minutes. Next, after the negative film was removed, the photosensitive resin layer was immersed in a 40 ° C. aqueous developer containing 2 parts by weight of sodium butylnaphthalenesulfonate (Perex NB-L, manufactured by Kao Corporation) and rubbed with a brush for 15 minutes. Thus, a photosensitive resin printing plate was obtained. The obtained photosensitive resin printing plate was printed on a coated paper (Ryuo Co., Ltd., Daishowa Paper Industries) with an aqueous ink (Aquapack 39 Ai, manufactured by Toyo Ink Mfg. Co., Ltd.). 150 lpi of the obtained printed matter
The optical density of a 30% halftone dot portion was measured using a reflection densitometer (DM-800).
(Dai Nippon Screen Co., Ltd.). The smaller the optical density, the smaller the thickness (dot gain) of the printed matter, and the brighter the printed matter, which is desirable. <Evaluation of plate strength> The obtained photosensitive composition was sandwiched between polyethylene terephthalates to prepare a photosensitive resin plate having a thickness of 1.0 mm, and was exposed to a high-pressure mercury lamp for 5 minutes. The product (tensile product) of the tensile strength and the elongation at break of the photosensitive resin plate after the exposure was determined under the conditions of a tensile speed of 200 mm / min and a mark length of 20 mm. A higher tensile product value indicates a higher plate strength.

Reference Example 1 (Synthesis of hydrophilic polymer) 119.0 parts of hexamethylene diisocyanate (manufactured by Nippon Polyurethane Industry Co., Ltd.)
62.0 parts of dimethylolpropionic acid (Fujii Yoshitsusho)
29.0 parts of polytetramethylene glycol (G-850, manufactured by Hodogaya Chemical Co., Ltd.) and 5.0 parts of di-n-butyltin dilaurate are dissolved in 300 parts of tetrahydrofuran, and this solution is mixed with 1 liter of a stirrer. The mixture was placed in a flask, heated to 65 ° C. while stirring, and the reaction was continued for 2 hours. An acrylonitrile butadiene oligomer having an amino group at a terminal in a separate container (HycarATB)
A solution prepared by dissolving 184.0 parts of N 1300 × 16 and Ube Industries, Ltd. in 270 parts of tetrahydrofuran was added to the above 1
It was added to the liter flask with stirring at room temperature.
Tetrahydrofuran was distilled off from the polymer solution under reduced pressure and dried under reduced pressure to obtain a polymer having a number average molecular weight of 6,700. Next, 100 parts of the polymer was added to tetrahydrofuran 1
An aqueous solution in which 2.4 parts of lithium hydroxide and 5.3 parts of magnesium acetate were dissolved in 100 parts of ion-exchanged water was added to the solution dissolved in 00 parts while stirring at room temperature.
After stirring for minutes, a hydrophilic polymer was obtained.

Example 1 12 parts of the above hydrophilic polymer obtained in Reference Example 1 and an acrylonitrile butadiene type random copolymer (JSR
N230SH 42 parts by Nippon Synthetic Rubber Co., Ltd., polybutadiene (JSR BR02L Nippon Synthetic Rubber Co., Ltd.)
15 parts, oligobutadiene acrylate (PB-
A, manufactured by Kyoeisha Chemical Co., Ltd.) 29 parts, ECH-modified phthalic acid diacrylate 10 parts, benzyl dimethyl ketal 1 part and hydroquinone monomethyl ether 0.5 part together with 40 parts of toluene and 10 parts of water by using a heating kneader.
By kneading at 05 ° C, and then distilling off the solvent under reduced pressure,
A photosensitive resin composition was obtained. A film in which the photosensitive resin composition is coated with a polyester-based adhesive on a polyethylene terephthalate film having a thickness of 125 μm,
The same polyethylene terephthalate film is sandwiched between mat films coated with an anti-adhesion layer (containing polyvinyl alcohol, propylene alcohol, and a surfactant) on the same polyethylene terephthalate film (so that the adhesive layer and the anti-adhesion layer come into contact with the photosensitive resin composition) and heated. 105 ° C, 100kgf with press
For 1 minute to obtain a photosensitive resin plate having a thickness of 3.0 mm.

The mat film having the anti-adhesion layer of the obtained photosensitive resin plate was peeled off, and a negative film having an image was adhered thereon, and the illuminance was measured with a high-pressure mercury lamp (manufactured by Dainippon Screen Co., Ltd.). Exposure was performed at 25 W / m ² for 5 minutes.
Next, after removing the negative film, sodium butylnaphthalenesulfonate (Perex NB-L, manufactured by Kao Corporation) 2
Immersed in an aqueous developer containing 40 parts by weight containing 40 parts by weight,
The photosensitive resin printing plate was obtained by rubbing the photosensitive resin layer with a brush for minutes. For the obtained photosensitive resin printing plate, an aqueous ink (Aquapack 39 indigo, manufactured by Toyo Ink Mfg. Co., Ltd.)
Printed on coated paper (Ryuo Court Daishowa Paper Industries). The halftone dot image of the obtained printed matter was high in resolution and sharp, and the optical density of a halftone portion of 150 lpi 30% was measured with a reflection densitometer (DM-800, manufactured by Dainippon Screen Co., Ltd.). %Met. Further, the photosensitive composition was sandwiched between polyethylene terephthalates to prepare a photosensitive resin plate having a thickness of 1.0 mm.
Exposure for a minute. When the photosensitive resin plate after this exposure was broken under the conditions of a pulling speed of 200 mm / min and a mark length of 20 mm, the product of tensile strength and elongation at break (tensile product) was 43765 kgf / cm ² %. , It was suggested to have excellent plate strength.

Example 2 A photosensitive resin plate was prepared in the same manner as in Example 1 except that EO-modified phthalic acrylate was used instead of ECH-modified phthalic diacrylate.
The obtained halftone dot image of the obtained printed matter has a high resolution and is clear, and the optical density of the halftone dot portion of 150 lpi 30% is 60.
%Met. The tensile product of the photosensitive resin plate is 4037
It was suggested that it had excellent plate strength at 0 kgf / cm ² %.

Example 3 In Example 1, 10 parts of ECH-modified phthalic diacrylate were replaced by 10 parts of ECH-modified phthalic diacrylate.
And a photosensitive resin plate was prepared in the same manner as in Example 1 except that 5 parts of 1,6-hexanediol dimethacrylate was used in combination. The halftone dot image of the obtained printed matter was high in resolution and sharp, and the optical density of the halftone dot portion of 150 lpi 30% was 60%. The tensile product of the photosensitive resin plate is 40
It was suggested that 657 kgf / cm ² % had excellent plate strength.

Example 4 The procedure of Example 1 was repeated, except that chlorinated polyethylene (manufactured by Daisorak H-135, Daiso KK) was used instead of the acrylonitrile-butadiene random copolymer. A resin plate was prepared.
The dot image of the obtained printed matter is high in resolution and clear,
The optical density of a halftone dot portion of 150 lpi 30% was 59%. The tensile product of the photosensitive resin plate is 42376 kgf
/ Cm ² % suggests excellent plate strength.

Example 5 In Example 1, styrene butadiene type random copolymer (JSR 1507) was used in place of polybutadiene.
A photosensitive resin plate was prepared in the same manner as in Example 1 except that Nippon Synthetic Rubber Co., Ltd.) was used. The dot image of the obtained printed matter is high in resolution and sharp, and has a resolution of 150 lpi30.
The optical density of the halftone dot portion was 59%. Further, it was suggested that the tensile product of the photosensitive resin plate had an excellent plate strength of 48710 kgf / cm ² %.

Example 6 A photosensitive resin plate was prepared in the same manner as in Example 1 except that polyisoprene (JSR IR10 manufactured by Nippon Synthetic Rubber Co., Ltd.) was used instead of polybutadiene. The dot image of the obtained printed matter is high in resolution and sharp, and the optical density of the dot portion of 150 lpi 30% is 59.
%Met. The tensile product of the photosensitive resin plate is 4237.
It was suggested that it had excellent plate strength at 0 kgf / cm ² %.

Comparative Example 1 A photosensitive resin plate was prepared in the same manner as in Example 1 except that 1,9-nonanediol dimethacrylate was used instead of ECH-modified phthalic acid diacrylate. The dot image of the obtained printed matter had poor resolution and was somewhat lacking in sharpness, and the optical density of the dot portion of 150 lpi 30% was 62%. Also, the tensile product of the photosensitive resin plate is
At 33775 kgf / cm ² %, the level was insufficient for the target plate strength.

Comparative Example 2 A photosensitive resin plate was prepared in the same manner as in Example 1 except that trimethylolpropane trimethacrylate was used instead of the ECH-modified phthalic acid diacrylate. The dot image of the obtained printed matter had poor resolution and was somewhat lacking in sharpness, and the optical density of the dot portion of 150 lpi 30% was 62%. The tensile product of the photosensitive resin plate was 36064 kgf / cm ² %, which was an insufficient level for the target plate strength.

Comparative Example 3 A photosensitive resin plate was prepared in the same manner as in Example 4 except that the ECH-modified phthalic acid diacrylate was not used. The halftone dot image of the obtained printed matter had poor resolution and was lacking in sharpness, and the optical density of the halftone dot portion of 150 lpi 30% was 68%. The tensile product of the photosensitive resin plate was 29144 kgf / cm ² %, which was an insufficient level for the target plate strength.

Table 1 shows the optical densities and tensile products of 150 lpi 30% halftone dots of the printed materials obtained in Examples 1 to 6 and Comparative Examples 1 to 3.

[0039]

[Table 1]

As is clear from Table 1, the addition of an ester compound of an ethylenically unsaturated alcohol and an acid having a cyclic site improves the plate hardness of the photosensitive resin plate and increases the thickness (dot gain) during printing. It can be seen that the reduction is also realized.

[0041]

As described above, the photosensitive resin plate of the present invention has excellent plate strength as compared with conventionally known photosensitive resin plates, has a small dot gain at the time of printing, and reproduces clear printing. , High-grade process color printing, etc., can be used for a wide range of brands. Furthermore, since the photosensitive resin plate can be developed in an aqueous system, the waste liquid of the developer can be adjusted to pH,
One of the great features is that it can be easily treated by a known waste liquid treatment technique such as the addition of an adsorbent or a flocculant or the treatment of microorganisms, which greatly contributes to the industry.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code FI G03F 7/004 501 G03F 7/004 501

Claims (2)

[Claims] 1. A photosensitive composition comprising (A) a thermoplastic elastomer, (B) an ester compound of an ethylenically unsaturated alcohol and an acid having a cyclic moiety, and (C) a photopolymerization initiator. Resin composition. 2. A photosensitive resin plate having at least a support and a layer of the photosensitive resin composition according to claim 1.