JPH01219833A - Photosensitive resin composition - Google Patents

Abstract

PURPOSE:To obtain a photosensitive resin compsn. which is most suitable for a material for flexographic plate by incorporating a polymer having a specified chlorine content and a specified glass transition temp., a hydrophilic polymer, a polymer or oligomer contg. a conjugated dienic hydrocarbon having an ethylenic unsatd. group at an terminal or in a side chain, and a photopolymn. initiator into the photosensitive resin compsn. CONSTITUTION:A polymer A having 10-50wt.% chlorine content and <=5 deg.C glass transition temp., a hydrophilic polymer B, an oligomer or a polymer C contg. a conjugated dienic hydrocarbon having an ethylenic unsatd. group at a terminal or in a side chain, and a photopolym. initiator D, are contained in the title compsn. The polymer A is obtd. by the polymn. of a monomer contg. Cl atom. If the Cl content of the polymer A is out of the above described range, the flexibility of the polymer is impaired, or the photosensitive resin becomes too rigid, or colored, generating undesirable result. Thus, a photosensitive resin compsn. having high rubber elasticity and superior resistance to water- base ink, being applicable to a material for flexographic printing plate, is obtd.

Description

Detailed Description of the Invention (Industrial Application Field) The present invention relates to a photosensitive resin composition that has rubber elasticity and is capable of aqueous phenomena, and particularly relates to a photosensitive resin composition that is applied to flexographic printing plates. .

(Prior art) Conventional photosensitive resin plates for flexographic printing are known to react with organic solvents, but these printing plates
There were safety problems for the human body and the environment, such as kP1 and flammability V1.

Therefore, as an alternative to this, a photosensitive resin composition capable of a water-based phenomenon has been proposed.

For example, a polymer containing a conjugated diene hydrocarbon and an α,β-ethylenically unsaturated carboxylic acid as essential components, and a monoolefinically unsaturated compound (a polymer and a photocommercially unsaturated compound, A method using a photosensitive resin composition containing a sensitizer (JP-A-52-134855), a conjugated diene hydrocarbon polymer or a copolymer of a conjugated diene hydrocarbon and a monoolefinic unsaturated compound There are photosensitive elastomer compositions (JP-A-60-211451) which contain a hydrophilic polymer compound, a non-gaseous ethylenically unsaturated compound, and a photopolymerization initiator as essential components. The composition can be developed with an aqueous developing solution, such as an alkaline aqueous solution or an alkaline water-organic solvent system, but since it is based on a conjugated diene hydrocarbon, it has poor ozone resistance and weather resistance as a flexographic printing plate. However, the problem of poor oxidation resistance has been addressed.

Therefore, the present inventors have discovered a photosensitive resin composition containing epichlorohydrin rubber, a hydrophilic polymer, an ethylenically unsaturated compound, and a photopolymerization initiator, and have overcome the above-mentioned problems.

(Problems to be Solved by the Invention) However, when a general-purpose polyfunctional low molecular Fd compound is used as the ethylenically unsaturated compound in the composition, the hardness of the cured product is excessively high and the rubber elasticity is low. A problem arose in that it was unsuitable for flexo printing plates due to its low temperature.

As far as hardness and rubber elasticity are concerned, there are some general-purpose oligoacrylates such as polyester urethane acrylate and polyether urethane acrylate that can hold up to 11!1, but these are not suitable for flexo printing plates because they have poor water-resistant ink properties. is unsuitable, and furthermore, J' ttt 6
There is also a proposal to use oligobutadiene acrylate of 000 to 10,000 (Japanese Unexamined Patent Publication No. 165843/1983), but this was of an in-house solvent development type.

(The first step to solving the problem) Therefore, the inventors of the present invention discovered that the inventors of the present invention have developed the following research: As a result of their investigation, they found that conjugated tsene-based hydrocarbon 3-auto oligomers or polymers having ethylenically unsaturated J1( By using the above-mentioned problem, the water-resistant ink was improved.In other words, the present invention solves the above-mentioned problems and improves the waterproof ink resistance.That is, the present invention solves the above problems and improves the waterproof ink resistance. Polymer with a glass transition temperature of 5°C or higher, (B)j3!
A photosensitive resin composition comprising an aqueous polymer, (C) a conjugated diene hydrocarbon-containing oligomer or polymer having an ethylenically unsaturated group at the terminal or side chain, and (1) a photopolymerization initiator. be.

The chlorine content of component (A) in the present invention is 50 to 1
Polymers with a glass transition temperature (hereinafter referred to as Tg) of 5°C or lower include a polymer containing 1 trillion chlorine, 1 small group, or a chlorine source. Contains: Obtained from a meeting with another jlj i1 that can be assembled with one. It can also be obtained by reacting chlorine or a t1η substance containing chlorine with a polymer that does not contain a chlorine source r. Specifically, the following can be mentioned. Epichlorohydrin polymer, epichlorohydrin-ethylene oxide copolymer, epichlorohydrin-propylene oxide (polymer and/or epichlorohydrin rubber, which is a copolymer of these and allyl glycidyl ether)
@Shun made HYDRIN, r1honze, t71121 made GEC) IRON, Zeoshan, Hevcules
HERCLORl manufactured by Ill), chlorinated polyethylene (Elasuren manufactured by Showa J-[-Ai, Osaka Soda T, industry) Daisolac manufactured by Shun, HORT manufactured by Hoechst n'jiJ
ALITZ 1Dow Made by Chemjca1913 D
OW CPE), vinyl chloride copolymer, vinylidene chloride, chlorinated polypropylene, chlorinated ethylene-propylene rubber, etc. What are these polymers? 11-
It may be used alone or in combination of two or more.

In the present invention, the chlorine content of the polymer (A) is 10 to
If it is outside this range, its flexibility will be impaired, its thermal stability will deteriorate, the photosensitive resin composition will be too hard, and it will be more likely to be colored, which is not preferable. Note that diene-based hydrocarbon polymers or their copolymers containing chlorine atoms r- have 3 carbon unsaturated bonds in the IE chain.
Because of this, it has the disadvantage that chemical stability such as weather resistance is inferior to the case with only saturated bonds. In addition, since the physical properties of the photosensitive resin composition after irradiation with light Q(() largely depend on the properties of the component (A) in the present invention, it is preferable that the component (A) is a woody rubber elastic body. Therefore, its Tg is necessarily 5°C or lower, and particularly preferably -10°C or lower.

In the present invention, in addition to the polymer as component (A), an elastomer having good compatibility with the polymer and having ozone resistance, such as acrylic rubber or polyurethane elastomer, may be blended.

In the present invention, the content of component (A) in the entire composition is 20,000 i after considering the physical properties and shape retention properties as a printing plate.
It is preferably 1% or more [0, especially 30IT+'% by weight or less, and from the viewpoint of photopolymerizability, it is preferably 80IT+'% or more, especially 7
01T! , : ! Preferably it is less than or equal to it%.

The hydrophilic polymer which is the component (B) of the present invention is water, or a developer containing 1:1 water, an alkaline aqueous solution, an acidic aqueous acid, a solvent, or a surfactant as a component.
A polymer that dissolves or swells (disperses).

Examples include polymers having hydrophilic groups such as hydroxyl groups, carboxyl groups, amino groups, and sulfonic acid groups and/or polyethylene glycol chains. Specific examples include polyvinyl alcohol, carboxyl methyl cellulose, hydroxyethyl cellulose, water-soluble polyurethane, and polyurea urethane, water-soluble polyester water-soluble epoxy compound, carboxyl group-containing acrylonitrile-butadiene copolymer, carboxyl group-containing styrene-butadiene copolymer, carboxyl group-containing polybutatsuene,
Polyacrylamide, sodium polyacrylate, polyurethane having a hydrophilic group such as a carboxyl group, polyurea urethane containing a carboxyl group, and polyamic acid 3 can be used, but are not limited to these. Incidentally, the above-mentioned metal salt may form a salt with an alkali metal, alkaline earth metal, aluminum, amine, aluminum t1, or the like.

The content of component (B) in the entire composition is preferably 5 to 50 iTCtJ%, particularly 7 to 40 tons 1□1%, taking into account water-based developability and water-based ink resistance.

In the present invention, the conjugated tenne hydrocarbon-containing oligomer or polymer having an ethylenically unsaturated group attached to the end or side chain of component (C) contains at least one terminal ethylenically group, and is a molecule! A300~10000
, particularly preferably 1,000 to 5,000, in which a high molecular weight polymer is further formed by free radical initiated chain growth addition polymerization. Specifically, for example, oligobutadiene (meth)acrylate, oligostyrene butanene (meth)acrylate, oligonitrile butanene (meth)acrylate, oligoisoprene (meth)acrylate, oligobutadiene urethane (methane acrylate, oligostyrene butanene (meth)acrylate, Genurethane (meth)acrylate, oligobutadienamide acrylate, etc. may be used alone or in combination, but are not limited thereto.

In the present invention, as component (C), conventionally known ethylenically unsaturated compounds may be used in combination with the above-mentioned oligomers or polymers. Suitable ethylenically unsaturated compounds include unsaturated esters of polyols, especially α- Such esters with methylene carboxylic acid, such as ethylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, glycerol diacrylate, 1,3-propanediol di(meth)acrylate, 1,4-butanediol diacrylate, (Meta)acrylate
), 1,2,4-butanetrioltri(meth)acrylate), 1,4-cyclohexanediol di(meth)acrylate, ■,6-hexanethiol di(meth)acrylate, trimethylolpropane tri(meth)acrylate Examples include diallyl phthalate, fumaric acid diethyl ester, maleic acid dibutyl ester, and N
Examples include N-substituted maleimide compounds such as -methylmaleimide, N-ethylmaleimide, and N-laurylmaleimide, and these may be used alone or in combination.

The content of component (C) in the entire composition is preferably from 1 to 50%, and if it is less than 1%, photopolymerizability will be impaired and no image will remain after development.

On the other hand, if the amount is more than 50'[< in%, shape retention will be impaired. Furthermore, the plates become hard and brittle after irradiation with light, making them unsuitable as flexo printing plates, which is not preferable. More preferably, it is 5 to 40 weights (11%).

As the photopolymerization initiator of component (r) in the present invention,
Examples include benzophenones, benzoins, acetophenones, benzyls, benzoin alkyl ethers, penzylalkyl ketals, anthraquinones, thioxanthones, and the like. Specifically, benzophenone, chlor benzophenone, benzoin, acetophenone, benzyl, benzoin derivatives ethyl ether, benzine impropyl ether, benzoin isobutyl ether, benol dimethyl ketal, benzyl ethyl Φ ketal, benzyl Isopropyl fist ketal, anthraquinone, 2-chloroanthraquinone, thioxanthone, 2
-There are chlor thioxanthone, etc.

These are contained in the composition in an amount of 0.01 to 1% of 5' RPi. If it is less than 0.01%, the ability to start a light session will be impaired. If it exceeds 5%, it is not preferable because the curing depth cannot be obtained due to its own light shielding, and the image is likely to be chipped during development. More preferably, it is 0.1 to 3 id%.

In the present invention, in order to prevent only thermal polymerization without suppressing the photo-crosslinking reaction, the requirements (A) to (11) are as follows.
In addition to D), (E) 0.001 to 5
You may contain mj=%. Useful thermal inhibitors include, for example, hydroquinone, hydroquinone monoethyl ether, catechol, pt-butylcatechol,
2,6-di also includes monobutyl-p-talesol.

In addition, the photosensitive resin composition of the present invention includes i+J plasticizers,
Liquid polybutane rubber, liquid polyacrylonitrile butadiene rubber, nightly polystyrene butanoene rubber, liquid imprene rubber, polyvinyl chloride, chlorinated polyethylene, chlorinated polypropylene,
It is possible to use relatively low-molecular-weight elastomers such as silica, fine powder of silica L'yP, etc.

The method of preparing a flexographic printing original plate using the photosensitive resin composition of the present invention is as follows: 1); Input the named components in (in this order) and use a suitable solvent, such as tetrahydrofuran, dioxane, methyl ethyl ketone, cyclohexanone, It can be prepared by dissolving it in chloroform and removing the solvent, and then heating and press-bonding it to a suitable support, such as a film made of polyester, polyethylene, polypropylene, etc. Also, a similar film can be formed on a different side from the support. Alternatively, a film coated or laminated with a thin layer of polyvinyl alcohol, polyacrylamide, hydroxypropyl cellulose, etc. which is soluble in an aqueous developer may be provided.

The ultraviolet rays used when curing the photosensitive resin plate using the composition of the present invention have a wavelength of 150 to 500 mμ, particularly 30 mμ.
Those in the wavelength range of 0 to 400 m are effective, and the light sources used are preferably low pressure mercury lamps, high IF mercury lamps, carbon arc lamps, ultraviolet rays, chemical lamps, xenon lamps, and zirconium lamps. The photosensitive resin plate made of the composition of the present invention is image-exposed by applying ultraviolet rays to a negative film having a transparent image using the light source described above, and then removing the non-image areas that are not exposed using a developer,
A relief image is obtained.

The developing solution contains 1:1 tap water, alkaline compounds such as sodium hydroxide and sodium carbonate as components,
It can contain a surfactant, a water-soluble 4T solvent, etc.

Note that the developer is preferably used at a temperature of 25°C to 45°C.

The photosensitive resin plate obtained using the composition of the present invention exhibits rubber elasticity and is useful as a flexographic printing plate. It also has excellent ink resistance, ink transfer properties, and printing durability. The photosensitive resin composition of the present invention is useful as a flexographic printing plate, and can also be applied to photorenost and sandblasting, and can also be used as an elastomer that is cured by ultraviolet rays, such as adhesives, films, etc. It can also be used for paints and other purposes.

(Function) The composition of the present invention contains, as a crosslinking agent, a conjugated diene hydrocarbon having an ethylenically unsaturated group at the terminal or side chain.
゛Because oligomers or polymers are used, the hardness after curing is not excessively large compared to the conventionally widely used polyfunctional low molecular weight Y (1 crosslinking agent), and after branching, it can be used as a conjugated diene rubber. Therefore, it has excellent rubber elasticity and excellent waterproof ink resistance after plate making, making it ideal for flexo printing plates.

The ozone resistance, which is a drawback of conjugated tsene rubber, can be overcome by combining l: and epichlorohydrin rubber, which does not have a single bond in the chain, as a pace polymer.

(Examples) The present invention will be specifically explained below with reference to Examples, but the present invention is not limited to these Examples.

In the examples, parts mean parts by weight.

Furthermore, the hardness of the flexographic printing plate obtained from the composition of the present invention,
Repulsion resilience, ethanol resistance and water resistance were measured using the following methods.

Hardness: Measured at 20°C by a spring type comfort test (type A) method according to JIS-6301.

Resilience modulus: A steel ball with a diameter of 10 m/m (weight 4.leg) was rolled at 200. It was dropped from a height of , and the height (a) at which it bounced back was read and expressed as (a/20) x 100%.

Ethanol resistance, water resistance: 50 x 20 .

Example 1 Hexame Senshi/Nison Abut 21. lIS, dimethylolpropionic acid 15. lH, polytetramethylene glycol (PG-1001-1 polyurethane 1-
Work! ) made by force) 7. A solution of EIS in 100 parts of methyl ethyl ketone is placed in a flask No. 11 equipped with a stirrer. In a separate container, acrylonitrile butadiene oligomer containing 7 terminal amino groups (Hycar ATBNX 130
0 X 1 B Ube Industries (11j'!lri55.3
A solution prepared by dissolving ffl< in 100 parts of methyl ethyl ketone is added to the IQ flask labeled L with stirring at room temperature. 1.0 part of dilauric acid/-n-butyltin was added and the flask was heated at 70° C. for 3 hours with continued stirring. The obtained polymer solution was dried under reduced pressure to remove methyl ethyl ketone, and the number 14 homogeneous molecules; i was 45,
000 hydrophilic polymer [I] was obtained.

1- Hydrophilic M polymer [I] 15 parts, 50 parts of polyepichlorohydrin (Ebichroma-H manufactured by Osaka Soda A Thin) as chlorine-containing 1 polymer, styrene-butane rubber (S
BR1507 (manufactured by wood synthetic rubber a) 10 cities, butadiene oligoacrylate (A-3025, Idemitsu Petrochemical 1@
), 1 part of benyl dimethyl ketal (manufactured by Irgacure 651, Ciba Geigy 11), and 0.5 part of hydroquinone methyl ether were kneaded at 105°C using a heating kneader, and after defoaming, the resulting photosensitive material The resin composition was heated in a heat press at 105°C and a pressure of loOkg/cJ between a 125μ thick polyester film and a polyester film coated on one side with 2 prs of polyvinyl alcohol on the same polyester film.
A sheet having a thickness of 2.8 cm was prepared by heating and pressing for 1 minute so that the polyvinyl alcohol coating layer was in contact with the photosensitive resin.

The polyester film of the last layer was peeled off to leave a polyvinyl alcohol film on the photosensitive resin layer -1-, and a negative film 1 having an image was secretly placed on the film 1- and a mercury film (manufactured by Dai II Hon Screen Co., Ltd.) was applied. , 11 exposures for 5 minutes at 25W/-F once. After removing the negative film, 0.5
'Hair: When developed according to a plan for 10 minutes at 40°C with a 1t% sodium hydroxide aqueous solution, the relief depth was 1.2. , an image pattern was obtained. This 1+l+i
The image pattern is faithful to the image of the negative film used +1
It was appearing.

Example 2 Terminal amine 7), (containing propylene oxide oligomer (
Jeffamine D-2000 Mikata Texaco Chemical■
A solution of M) 20m< in 30 parts of tetrahydrofuran was added at room temperature to a solution of 4.4 parts of pyromellitic anhydride dissolved in 20 parts of tetrahydrofuran with stirring.

Acrylonitrile-butadiene oligo containing 7 terminal amino groups? -(Hycar ATBNX 1300 X 1
6 ur'? (', manufactured by Kosan 9 (1)) in a 4-part solvent of 100 parts of tetrahydrofuran and 50 parts of methanol, and stirred at room temperature. The reaction solution of pyromelli-sothoic acid was added to make 7 portions of the polyamic acid solution. After casting this solution, the solvent was removed by drying with a Makoto bar to obtain a shallow water polymer [II].

1° hydrophilic polymer [■ 20%, epichlorohydrin rubber (Ebichroma-1 (manufactured by Osaka So V 123) 50%
1 part, butane oligoacrylate (A-3025, manufactured by Idemitsu Petrochemical Co., Ltd.) 28.5 parts, pennolmethyl ketal 1 part, and hydroquinone monomethyl ether 0.5 parts
When a relief pattern was obtained in the same manner as in Example 1, a relief pattern with a relief depth of 1 + ww, which faithfully represented the image of the negative film, was obtained.

Example 3 Hydrophilic polymer obtained in Example 1 [5.5 parts of IF, 52.5 parts of epichlorohydrin rubber (Ebichroma-H, manufactured by Osaka Sodaho Co., Ltd.), epichlorohydrin oligomer (L-
1 Osaka・11 ■Tsuji! ) 15 parts (manufactured by Idemitsu Petrochemical) 15 parts, butadiene oligoacrylate (A-3025 manufactured by Idemitsu Petrochemical 1 Thin) 23
．． A relief pattern was obtained in the same manner as in Example 1 using 5 parts of dimethyl benzyl ketal, 1 part of dimethyl benzyl ketal, and 0.5 parts of hydroquinone monomethyl ether, and the relief depth was 0.9 m, which faithfully represented the image of negative film 1 at +Ig.

Obtained relief pattern.

Example 4 In Example 2, epichlorohydrin copolymer (epichlorohydrin 92 mol%,
Allyl green ether 8 mol% coΦ゛ combination, Ebichroma-HG Osaka Soda Co., Ltd.), oligobutadiene urethane methacrylate instead of butadiene oligoacrylate (Nl5SO-PB TE-200Fl, manufactured by Kikutsu Tsuji Stop Co., Ltd.)
A relief pattern was obtained in the same manner as in Example 2, except that a relief pattern was obtained that faithfully reproduced the negative film image. I was rejected.

Example 5 Copolymer of isobutylene and maleic anhydride (isopane
) -4, 200 parts of clareisoprene chemical [+ strength], 400 parts of methanol and 2-methylimidazole 3
Place 1 part in a flask equipped with a reflux condenser and stirrer, and add 64
The reaction was carried out at ℃ for 8 hours. The reaction solution was cast and dried under reduced pressure to form a hydrophilic polymer.

L hydrophilic polymer [■ 15 parts, Ebichlor Hitolino T, (Ebichroma-H manufactured by Osaka Soda Ka) 55 parts, oligobutadiene urethane acrylate (Polybd A
CR-LC Idemitsu Petrochemical! ) 21) 20ffl<, 8.5 parts of hexamethylene diacrylate, 1 part of dimethylbenzyl ketal and 0.5 parts of hydroquinone monomethyl ether) A relief pattern was obtained in the same manner as in Example 1. In this case, the developer is sodium hydroxide/
2-(2-Butoxyethquin) ethanol/aqueous solution (
Sodium hydroxide 0.4ffi<, 2-(2-butoxyethoxy)ethanol 15m, water 84.6ffi<)
This is the same as in Example 1 except that .

Example 6 As a hydrophilic polymer, 20 parts of hydroxypropyl methylcellulose (manufactured by TC-5R Shin-Etsu Chemical Co., Ltd.), epichlorohydrin copolymer (τ mol copolymer of epichlorohydrin and ethylene oxide, manufactured by 11 Ki Zeo 71E, Iy)
drin 200) 50 parts, acrylonitrile butadiene oligoacrylate () [YCARVTBNX
1300 x 23 Ube Industries ■) and monoacrylate of phenol ethylene oxide adduct (Alonisox M 102 Higashi 1ib Synthetic Chemistry C)
Notoichi; 28.5 parts of Tsuji mixture, 1 part of dimethylbenzyl ketal and 0.5 parts of hydroquinone monomethyl ether
When a relief pattern was obtained in the same manner as in Example 1, a relief that faithfully represented the negative film image at +Tf was obtained.

Example 7 Methacrylic acid number Acrylonitrile-butadiene copolymer, 25 parts of Paul 1072 (manufactured by Zeon Yusho), epichlorohydrin rubber (Ebichroma-H1 Osaka Sojfi1)
111) 50ffi, oligobutadienamide acrylate (Kyoeisha Urashi ■sample) 13.5 parts, hexamethylene diacrylate 10 parts, dimethylbenzyl ketal 1
A relief pattern was obtained in the same manner as in Example 1 using 0.5 parts of hydroquinone monomethyl ether. In this case, the developer used is hydroxide, as in Example 5.
2-(2-Butoxyethquin) ethanol/aqueous solution (
Sodium hydroxide 0.4 parts, 2-(2-butoxyethquine) ethanol 15 parts, water 84 parts. E39+S), both relief images at a depth of 1 ms faithfully reproduced both images of the negative film.

Comparative Examples 1 to 3 Sheets of photosensitive resin compositions were prepared in the same manner as in Example 1 except that 23.5 parts of each of the crosslinking agents shown in Table 1 were used instead of butadiene oligoacrylate in Example 1. I got it. An attempt was made to create a relief using the same procedure, but clear images could not be formed.

Reference Example The measurements of hardness, impact resilience, ethanol resistance and water resistance of the reliefs obtained in Examples 1 to 7 and Comparative Examples 1 to 3 are shown in Table 1. As is clear from Table 1, the photosensitive resin composition of the invention uses a conjugated diene hydrocarbon-containing oligomer or polymer having an ethylenically unsaturated group at the terminal or side chain as a crosslinking agent, so it cannot be used as a crosslinking agent. Compared to the F-crosslinking agent, it makes the hardness of the cured product excessively high, has excellent rubber elasticity, and is also excellent in water-based ink resistance, making it ideal for flexographic printing plates.

Patent applicant: Tot1bo Co., Ltd.

Claims (1)

[Claims] (A) a polymer with a chlorine content of 10 to 50% by weight and a glass transition temperature of 5°C or less, (B) a hydrophilic polymer,
A photosensitive resin composition comprising (C) a conjugated diene hydrocarbon-containing oligomer or polymer having an ethylenically unsaturated group at the terminal or side chain, and (D) a photopolymerization initiator.