JPS61246742A - Photosensitive resin composition - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to photosensitive resin compositions. More specifically, the present invention relates to a photosensitive resin composition that can use water or an aqueous solvent as a developer and has excellent resistance to aqueous inks and is suitable as a printing relief plate.

The photosensitive resin composition of the present invention is suitable for printing relief plates, but can also be used for offset plate layers, screens, resists, etc.

Prior Art Conventionally, photosensitive resin compositions for letterpress printing include those based on liquid unsaturated polyester, those based on polyvinyl alcohol, those based on water-soluble nylon, and those based on alcohol-soluble nylon. There are known products that use a base material, styrene copolymer as a base material, 1,2-polybutadiene as a base material, etc., but those that use liquid unsaturated polyester as a base material are liquid. This makes it inconvenient to handle, and it also has the disadvantage of requiring the use of alkaline water or a special air knife for development.

Polyvinyl alcohol-based materials and water-soluble polyamide-based materials have the advantage of being able to use water during development, but have the disadvantage that they are inferior in water resistance and cannot be printed using water-based inks. There is. Those based on cellulose acetate succinate have the disadvantage that they require the use of alkaline water for development and are not resistant to water-based inks. Products based on alcohol-soluble nylon have a serious safety drawback in that flammable alcohol must be used for development, while products based on styrene-isoprene-styrene copolymer However, this method has a serious drawback in terms of occupational safety and health, as it requires the use of a halogenated organic solvent as a developer.

Problems to be Solved by the Invention The object of the present invention is to obtain a photosensitive resin composition that can be developed with water and has excellent resistance to water-based inks, and is particularly suitable for letterpress printing.

Means for Solving the Problems The present invention provides (i) a polymer having a tertiary nitrogen atom and a polymerizable double bond residue (A
), (ii) a monomer (B) having a free acid group that can be quaternized with the tertiary nitrogen atom of (A) and an α,β-ethylenically unsaturated bond, (iii) a photopolymerizable unsaturated Compound (C) and (i
v) A photosensitive resin composition containing a photopolymerization initiator (D) is provided.

The polymer (A) in the composition of the present invention is quaternized by the monomer (B) and is water-soluble or water-dispersible. This composition is molded into a sheet and adhered to a suitable substrate, such as a letterpress printing substrate, to form a photosensitive layer. When a negative film is passed over this photosensitive layer and exposed to ultraviolet light, the exposed area becomes a polymer ( A), the monomer (B) and the photopolymerizable unsaturated compound (C) copolymerize and become insoluble in water. On the other hand, since the unexposed areas do not polymerize and can be easily dissolved and removed with water, the relief plate can be developed by simply washing with water.

Therefore, the polymer (A) of the present invention has a quaternary monomer (B).
A tertiary substance that is water-soluble or water-dispersible when graded.
It is sufficient that the compound has a polymerizable double bond residue and a molecular weight that can be made insoluble by photopolymerizing the photopolymerizable unsaturated compound (C) with the photopolymerizable unsaturated compound (C).

The double bond residue does not necessarily have to be so disturbed that it alone can be insolubilized. This insolubilization is mainly achieved by the monomer (B) and the photopolymerizable unsaturated compound (C).

The polymer (A) used in the present invention contains 3 to 50 mol%, preferably 10 to 30 mol%, of α,β-ethylenically unsaturated monomer (a) having a tertiary nitrogen atom, polymerizable unsaturated Monomer (b) 5 to 95 mol%, preferably 20 to 40 mol%,
Copolymerized with conjugated diene monomer (c) 0 to 90 mol%, preferably 20 to 60 mol%, and has a weight average molecular weight of 5
000-500°000, preferably 10,000-2
A copolymer resin of 50,000 is preferred.

α having a tertiary nitrogen atom used in the polymer (A).

Examples of the β-ethylenically unsaturated monomer (a) include dimethylaminoethyl (meth)acrylate, diethylaminoethyl (meth)acrylate, di-t-butylamino (meth)acrylate, dimethylaminopropyl (meth)acrylamide, etc. Formula: % Formula % [In the formula, R1 is hydrogen or methyl, (CH2)n is ethylene, trimethylene, butylene group, R4 is hydrogen, carbon 1
It represents an alkyl group having 1 to 4 carbon atoms, a hydroxyalkyl group having 1 to 4 carbon atoms, and an alkoxyalkoxy group having 1 to 4 carbon atoms. A monomer represented by ko is used.

Examples of the polymerizable unsaturated monomer (b) that can be used in the polymer (A) include styrene, α-methylstyrene, vinyltoluene, acrylonitrile, vinyl chloride, vinylidene chloride,
(meth)acrylic acid ester, (meth)acrylic acid amide, dicyclopentenyl (meth)acrylate, dicyclopentenoxyethyl (meth)acrylate, dicyclopentenoxypropyl (meth)acrylate, diethylene glycol dicyclopentenyl monoether Examples include (meth)acrylic acid esters, which can be used alone or in combination. The above (meth)acrylic acid esters include methyl (meth)acrylate, (meth)acrylate,
Ethyl acrylate, n-butyl (meth)acrylate, (
2-ethylhexyl meth)acrylate is preferable.

Examples of the polymerizable unsaturated monomer (c) include conjugated diene-based unsaturated monomers, such as conjugated diene-based hydrocarbons such as butadiene, isoprene, dimethylbutadiene, and chloroprene, which are used alone or in combination. be able to.

The monomer (B) having an α,β-ethylenically unsaturated bond contains a free acid group and a photopolymerizable unsaturated compound (C) for quaternizing the polymer (A) to make it water-soluble. It has a polymerizable unsaturated bond that can be photopolymerized to make it insoluble in water.

Examples of free acid groups include carboxylic acid groups, phosphoric acid groups, and sulfonic acid groups. These monomers (B) have the formula: %Formula% R,0 CH2=CC0NHRt OP OH:OH R,O I CH,=C-Coo-R,-0-S-OH:R,0 CH,= C-CONH-R, -0-S-OH; [wherein,
R, is hydrogen or methyl, R3 is (CH2)n (n is I
~6), R3 represents a Cl-08 alkylene group or a phenylene group] are particularly suitable.

α,β-ethylenically unsaturated monomer containing carboxylic acid group (
Examples of B) include (meth)acrylic acid, maleic acid, fumaric acid, citraconic acid, etc., and examples of the α,β-ethylenically unsaturated monomer (B) containing a sulfonic acid group include 2-hydroxy Ethyl acryloyl phosphate, 2
-Hydroxypropyl acryloyl phosphate, 2-
Examples include hydroxy-α-chloropropyl acryloyl phosphate, and these acid group-containing α,β-ethylenically unsaturated monomers can be used alone or in combination.

As the photopolymerizable unsaturated compound (C) used in the present invention,
It may be a conventionally known compound, and preferably is a non-gaseous ethylenically unsaturated compound containing at least one terminal ethylenic group, and is compatible with the polymer (A). For example, ethylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate, tetraethylene glycol di(meth)acrylate, 1,4-butanediol di(meth)acrylate, l,6- Hexanethiol di(
esters of unsaturated carboxylic acids such as meth)acrylate, 1,4-cyclohexanediol di(meth)acrylate, propylene diol di(meth)acrylate, neopentyl glycol di(meth)acrylate, and pentaerythritol tetra(meth)acrylate; N,
N'-methylenebisacrylamide, N,N'-ethylenebisacrylamide, N.

No-Hexamethylenebisacrylamide, N, No-
Unsaturated amides such as xylylenebisacrylamide, N-(β-hydroquinethyl)methacrylamide, N,N'-bis(β-hydroxyethyl)acrylamide:
Urethanized (meth)acrylates derived from 2-hydroxyethyl (meth)acrylate and isocyanate compounds: Mono- or di(meth)acrylates of diepoquine polyethers modified with aromatic polyhydric hydroxy compounds, such as bisphenol and novolak compounds. ) acrylate, etc., and these are not limited to one type and may be used as a mixture of two or more types, but those with low hydrophilicity are preferred.

Examples of the photopolymerization initiator (D) used in the present invention include benzoin ethers such as benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, and benzoin butyl ether; benzophenones such as benzophenone and 0-penzoylmedyl benzoate; xanthone, thioxanthone , 2-chlorothioxanthone, 2-isopropylthioxanthone and other xanthones; acetophenone, trichloroacetophenone, 2゜2
-Jethoxyacetophenone, 2,2-dimethoxy-2
- Acetophenones such as phenylacetophenone: Others, benzyl-2-ethyl-anthraquinone; methylbenzoylformate; 2-hydroxy-2-methyl-
Propiophenone: 2-hydroxy-4-isopropyl-2-methylpropiophenone; 1-hydroxycyclohexylphenyl ketone, etc., and can be used alone or in combination.

The photosensitive resin composition of the present invention comprises the above polymer (A) 30 to
The α,β-ethylenically unsaturated monomer (B) containing an acid group neutralizes 20 to 250% by weight of the amino groups of the polymer (A) relative to 90% by weight, preferably 40 to 80% by weight. Generally, 1 to 60% by weight of the photopolymerizable unsaturated compound (c) is blended, and 5 to 70% by weight of the photopolymerizable unsaturated compound (c), preferably 10 to
It is obtained by blending 55% by weight of the photopolymerization initiator (D) and 0.01 to 20% by weight, preferably 0.05 to IO% by weight.

This composition may optionally contain conventionally known polymerization inhibitors such as hydroquinone, p-methoxyphenol, 2,5-di-t-butylcatechol, benzoquinone, naphthoquinone, 2,5-diphenyl-p - benzoquinone, phenothiazine, etc., dyes such as eosin Y10-zbengal, malachite green, methylene blue, dialkyl phthalate, dialkyl fumarate, dialkyl sebacate, dialkyl itaconate, alkyl phosphate, (poly)ethylene glycol,
Plasticizers such as (poly)ethylene glycol ester and (poly)ethylene glycol ether can be added. The photosensitive resin composition according to the present invention can be produced by extrusion molding,
Uniform 0.01~1 by methods such as calendar molding
It is formed into a 0.00 mm sheet, pressed onto a support via an adhesive layer, and exposed to ultraviolet light through a suitable negative film. Polymerization proceeds in the exposed area, and water,
If a polymerized latent image is formed that is insoluble in alkaline or organic solvents, and then the unpolymerized materials in the non-exposed areas are removed using water, a printing relief plate with excellent resistance to water-based inks can be obtained very easily. It will be done.

Effects of the Invention Although the photosensitive resin composition of the present invention is essentially water-soluble, a plate obtained from it is easily polymerized by ultraviolet rays and becomes insoluble in water. Therefore, when a negative film is irradiated with ultraviolet rays and washed with water, the resin remains only in the image area and a printing plate is easily formed. Therefore, development can be easily carried out by simply washing with water, and since the formed print is water resistant, printing with water-based ink is possible. The photosensitive resin composition of the present invention is particularly useful for letterpress printing plates, but can also be used for offset plates, screen plates, resist plates, etc.

Example 1 A copolymer resin (M
W=100,000) 40 parts by weight, Viscoat 200
0 (manufactured by Sanyo Kasei Co., Ltd.: halfester of 2-hydroxyethyl acrylate and phthalic acid) 14 parts by weight, 17 parts by weight of hydroxypropyl acrylate, 16.6 parts by weight of 1.6-hexanediol diacrylate, 2.2-dimethoxy - A photosensitive resin composition consisting of 2.16 parts of 2-phenylacetophenone and 0.24 parts by weight of 2゜6-di-t-butylcatechol was placed on a 0.18 mm thick iron plate to a thickness of about 0.5 am. Calender molding was carried out at a temperature of about 80°C.

A negative film with a line drawing or the like is vacuum-adhered to the surface of the resin composition obtained here, and after irradiating it with a 350W chemical lamp for 1 minute from a distance of 6cm, the negative is peeled off, and it is heated with a nylon brush in water at 40°C. After 2 minutes of elution, an image of Shore Al [95° faithful to negative film] was obtained. When an attempt was made to print the relief plate obtained in the above plate-making process on kraft paper using a stack-type flexo printing machine using water-based flexo ink, a dark image was maintained for more than 2 hours at 50 m/min. Furthermore, this plate is 2.5cxX5.
ocm specimens were cut into 40.0 cm test pieces and placed in water containing 30.01 parts by weight of water, 30.01 parts by weight of NaCO and 5 parts by weight of butyl cellosolve.
When immersed for 2 hours at ℃, the relief surface had a total thickness of 6.
It was confirmed that the water resistance was excellent even if the swelling was only 4%.

Comparative Example I 10 parts by weight of tetraethylene glycol and 6 parts by weight of acrylamide were added to 80 parts by weight of a water-soluble polyamide resin in which 52 mol% of hydrogen atoms at the α-position of polyε-cabramide (nylon 6) were substituted with dimethylamino groups. , 2 parts by weight of N,N'-methylenebisacrylamide, 2.5 parts by weight of benzoin isobutyl ether, 0.4 parts by weight of 2,6-di-t-butylcatechol, and 0.4 parts by weight of p-methoxyphenol.
1 part by weight was mixed and dispersed in a pressure kneader at room temperature and extruded into a rod shape using an extrusion molding machine.
Calendar molded on m-thick color galvanized iron, total thickness 0°96
A photosensitive composition sheet of m+n was obtained.

When this material was plate-made in the same manner as in Example 1, a relief image with a Shore A hardness of 96° and 0.66++++n was obtained. This one costs 2.5ca! X5. Oam test pieces were cut into test pieces, and 40% of each were placed in water and water containing 5% by weight of Na COs IM and 5% by weight of butyl cellosolve.
When immersed at ℃ for 2 hours, the relief surface in all cases swelled by 20% or more over the entire thickness.

Example 2 β-
4.8 parts by weight of methacryloxyethyl phosphoric acid, 23.9 parts by weight of phenoxyethyl acrylate, 23.9 parts by weight of 1.6-hexanediol acrylate, 2.16 parts by weight of 2.2-dimethoxy-2-phenylacetophenone, A photosensitive resin composition containing 0.24 parts by weight of 2.6-di-t-butylcatechol was calender-molded on a 0.18 mm thick iron plate to a thickness of about 0.5 mm at a temperature of about 80°C.

Examples of the resin compositions obtained here! When exposed under the same conditions as above and eluted for 50 seconds with a nylon brush in water at 40°C, a relief image faithful to the negative film with a Shore A hardness of 84° was obtained.

Furthermore, this plate is 2.5czX5. When the specimen was cut into a test piece of 0 cm and immersed in water containing 30.01 parts by weight of water, 30.01 parts by weight of NaCO, and 5 parts by weight of butyl cellosolve at 40°C for 2 hours, the relief surface swelled by 7°9% over the entire thickness. Further, when a letterpress material made of the above composition was printed on kraft paper using the same printing machine as in Example 1 at a speed of 150 m/11 inch, a sharp image was maintained for 2 hours.

X number of cars l 2-acrylamido-2-methylpropanesulfonic acid 4.8 parts per 50 parts by weight of the same copolymer resin as in Example 1
Parts by weight, 23.9 parts by weight of urethane bonding compound of 2-hydroxyethyl acrylate and butyl isocyanate, 1
．． 23.9 parts by weight of 6-hexanediol acrylate,
2,2-dimethoxy-2-phenylacetophenone 2,
16 parts by weight, 2°6-di-t-butylcatechol 0.2
A photosensitive resin composition containing 4 parts by weight was calender-molded at a temperature of about 80° C. to a thickness of about 1.9 mm on a 0.18+ nm thick iron plate.

When the resin composition obtained here was exposed to light under the same conditions as in Example 1 and eluted in water at 40°C for 1 minute with a nylon brush, a relief image faithful to the negative film with a Shore A hardness of 76° was obtained. Ta.

Furthermore, this plate is 2.5C shoulder x 5. When the relief surface was cut into 0cm test pieces and immersed in water containing 1 part by weight of NaCO30, 01 parts by weight, and 5 parts by weight of butyl cellosolve at 40°C for 2 hours, the relief surface swelled by 9°6% in the entire thickness. When this product was further printed for 1 hour under the same conditions as in Example 2, a sharp image was maintained.

Patent Applicant: Chip Systems (nee Nis A)
Incoholated

Claims (1)

[Claims] 1. (i) a polymer (A) with a molecular weight of 5,000 to 500,000 having a tertiary nitrogen atom and a polymerizable double bond residue; (ii) a tertiary nitrogen atom in (A); A monomer (B) having a free acid group and an α,β-ethylenically unsaturated bond that can be quaternized with (iii) a photopolymerizable unsaturated compound (C) and (iv)
A photosensitive resin composition containing a photopolymerization initiator (D). 2. The polymer (A) contains (a) 5 to 95 mol% of an α,β-ethylenically unsaturated monomer (a) having a tertiary nitrogen atom, (b) a polymerizable unsaturated monomer (b) ) 5 to 95 mol % and (c) a conjugated diene system (c) 0 to 90 mol %. 3. The second α,β-ethylenically unsaturated monomer (a) having a tertiary nitrogen atom is a (meth)acrylic acid ester or (meth)acrylamide having a tertiary amino group
The photosensitive resin composition described in . 4. The photosensitive resin composition according to item 2, wherein the polymerizable unsaturated monomer (b) is a (meth)acrylic ester or (meth)acrylamide. 5. Monomer with α,β-ethylenically unsaturated bond (B
) is the following general formula: ▲There are mathematical formulas, chemical formulas, tables, etc.▼; ▲There are mathematical formulas, chemical formulas, tables, etc.▼; ▲There are mathematical formulas, chemical formulas, tables, etc.▼; ▲There are mathematical formulas, chemical formulas, tables, etc.▼; ▲There are mathematical formulas, chemical formulas, tables, etc.▼; ▲There are mathematical formulas, chemical formulas, tables, etc.▼; [In the formula, R_1 is hydrogen or methyl, R_2 is (CH_
2) n (n is 1 to 6), and R_3 is C_1 to C_6
2. The photosensitive resin composition according to item 1, which is selected from monomers represented by the following: alkylene group, phenylene group. 6. The photosensitive resin composition according to item 1, wherein the photopolymerizable unsaturated compound (C) is a terminal ethylenic group composition. 7. The first photopolymerization initiator (D) is benzoin ether, acetophenone, benzophenone, or a ketal derivative
The photosensitive resin composition described in . 8, (i) Weight (A) 30-90% by weight (ii) Half-weight (B) 1-60% by weight (iii) Photopolymerizable unsaturated compound (C) 5-70% by weight (iv) Photopolymerization A photosensitive resin composition containing 0.01 to 20% by weight of an initiator (D).