JP2940006B2 - Photosensitive resin printing plate - Google Patents

Description

Description: FIELD OF THE INVENTION The present invention relates to a photosensitive resin printing plate having rubber elasticity, capable of causing water-based phenomena, and having excellent ink resistance, and in particular, the present invention is intended for flexographic printing. It relates to a useful photosensitive resin printing plate.

(Prior art) Conventional photosensitive resin plates for flexographic printing are known to be phenomena caused by organic solvents, but these printing plates have problems in safety to humans and the environment such as toxicity and flammability. Was.

Therefore, as an alternative, a photosensitive resin composition capable of aqueous phenomenon has been proposed.

For example, a copolymer containing a conjugated diene-based hydrocarbon and an α, β-ethylenically unsaturated carboxylic acid or a salt thereof as essential components, a monoolefinically unsaturated compound and a photopolymerizable unsaturated monomer, Methods using a photosensitive resin composition containing a photosensitizer (JP-A-52-134655, JP-A-53-134655)
No. -10648, No. 61-22339), a conjugated diene-based hydrocarbon polymer or a copolymer of a conjugated diene-based hydrocarbon and a monoolefinic unsaturated compound and a hydrophilic polymer compound, a non-gas Elastomer composition containing a linear ethylenically unsaturated compound and a photopolymerization initiator as essential components (see JP-A-60-211451), a hydrophobic oligomer containing an α, β-ethylenically unsaturated group, A photosensitive resin composition containing an estramer water-swellable substance and a photopolymerization initiator as essential components (see JP-A-60-173055).
Etc.

In order to improve the mechanical strength and rebound resilience of the printing plate, a photosensitive resin composition containing hard organic fine particles (see JP-A-63-8648) and an improvement in the ink receptivity of the printing plate Resin composition having a two-phase structure, containing a diazo compound and a dichromate in a continuous phase and having a dispersed phase of 10 μm or less (see Japanese Patent Publication No. 59-36731).
Etc.

(Problems to be Solved by the Invention) The former in the above composition can be developed with an aqueous developer, for example, an alkaline aqueous solution or an alkaline aqueous solution-organic solvent system, but a phenomenon caused by so-called domestic water having a pH of 5.0 to 9.0. And many problems such as insufficient ink resistance of the relief portion.

Also, the latter in the above composition must contain a hydrophilic component in the continuous phase in order to enable aqueous development, in which case the content of the hydrophilic component is thermodynamically safe.
It is necessary to increase the content of the dispersed phase forming component. Also in this case, it is difficult to achieve both water developability and ink resistance of the relief portion.

Further, the photosensitive resin composition is basically required to have optical characteristics, that is, light transmittance, and good compatibility between constituent raw materials. Accordingly, since the hydrophilic polymer contained in the composition is inherently high in polarity, it is preferable that the other raw materials to be mixed have high polarity. However, polymers of conjugated diene-based hydrocarbons generally have low polarity, and thus have the disadvantage that the types of hydrophilic polymers having good compatibility and the mixing ratio are limited.

(Means for Solving the Problems) As a result of intensive studies, the present inventors have been able to solve the above-mentioned problems by controlling the phase structure of the photosensitive resin printing plate.

That is, the present invention includes particles in which a phase mainly composed of a hydrophilic polymer exists around a phase mainly composed of a non-crosslinked hydrophobic polymer, a compound containing an ethylenically unsaturated group, and a photopolymerization initiator. This is a photosensitive resin printing plate obtained by developing a photosensitive resin printing original plate to be developed.

The particles in the present invention are composed of at least two phases having a phase mainly composed of a hydrophobic polymer and a phase mainly composed of a hydrophilic polymer, and are composed of three or more phases having a plasticizer and the like as necessary. Is also good. As shown in FIG. 1, each phase in the particle has a phase (I) mainly composed of a hydrophobic polymer near the center of the particle and a phase (II) mainly composed of a hydrophilic polymer. It exists around the phase (I). The content ratio of each phase in the particles may be arbitrary. In each phase in the particle, a hydrophobic polymer is essential in the phase (I), a hydrophilic polymer component is essential in the phase (II), and the phase (I) may contain a hydrophilic component. (II) may contain a hydrophobic component. In this case, the composition ratio is optional, and the particle size and the particle size distribution may be optional, but the particle size is preferably from 0.01 μm to 100 μm in view of resolution and developability.

The phase structure of the photosensitive resin printing plate in the present invention, the particles described above as a dispersed phase when observed with a microscope, the particle size of the particles is from 0.01 to several hundred μm, by hydrophobic dye and hydrophobic polymer and hydrophilic polymer by dyeing It can be seen that there is a phase mainly composed of, and a continuous phase contains a hydrophobic component and a hydrophilic component. The composition ratio between the dispersed phase and the continuous phase in the present invention is arbitrary.

As the photosensitive resin composition for forming the photosensitive resin printing plate of the present invention, a hydrophobic polymer, a hydrophilic polymer, a cross-linking agent and a photoinitiator are essential components. Polymers having a temperature of 5 ° C. or less, including those used as general-purpose elastomers. For example, a polymer obtained by polymerizing a conjugated diene-based hydrocarbon, or a copolymer obtained by polymerizing a conjugated diene-based hydrocarbon and a monoolefin-based unsaturated compound, a polymer containing no conjugated diene-based hydrocarbon, and the like. And non-crosslinked polymers are preferred.

As the conjugated diene hydrocarbon, 1,3 butadiene, isoprene, chloroprene and the like are used. The conjugated diene-based hydrocarbon may be used alone or as a mixture of two or more.

Monoolefinic unsaturated compounds include styrene,
α-methylstyrene, o-methylstyrene, m-methylstyrene, P-methylstyrene, acrylonitrile, methacrylonitrile, vinyl chloride, vinylidene chloride, acrylamide, methacrylamide, vinyl acetate, acrylate, methacrylate, etc. Is done.

Examples of a polymer obtained by polymerizing a conjugated diene-based hydrogenated carbon or a polymer obtained by polymerizing a conjugated diene-based hydrogenated carbon and a monoolefin-based unsaturated compound include a butadiene copolymer, an isoprene polymer, and chloroprene. Polymer, styrene-butadiene copolymer, styrene-isoprene copolymer, styrene-chloroprene copolymer, acrylonitrile-butadiene copolymer, acrylonitrile-isoprene copolymer, acrylonitrile-chloroprene copolymer, methyl methacrylate-butadiene Copolymer, methyl methacrylate-isoprene copolymer, methyl methacrylate-chloroprene copolymer, methyl acrylate-butadiene copolymer, methyl acrylate-isoprene copolymer, methyl acrylate-chloroprene copolymer, acrylonitrile − Diene - styrene copolymer, acrylonitrile - styrene copolymers, acrylonitrile - chloroprene - styrene copolymer.

Examples of the polymer containing no conjugated diene-based hydrocarbon include an elastomer containing a specific amount of chlorine and a non-conjugated diene-based hydrocarbon.

Those showing rubber elasticity have a chlorine content of 50 to 10% by weight
Polymers having a glass transition temperature (hereinafter referred to as Tg) of 5 ° C. or lower include polymerization of monomers containing a chlorine atom,
Alternatively, it is obtained from copolymerization with another monomer which can be copolymerized with a monomer containing a chlorine atom. It can be obtained by reacting chlorine or an active substance containing chlorine with a polymer not containing a chlorine atom, and specific examples thereof include the following. Epichlorohydrin polymer, epichlorohydrin-
Ethylene oxide copolymer, epichlorohydrin-propylene oxide copolymer and / or epichlorohydrin rubber which is a copolymer of these with allyl glycidyl ether [Epichromer, Goodvich manufactured by Osaka Soda Kogyo Co., Ltd.
HYDRIN manufactured by ZEON Corporation, GECHRON manufactured by Zeon Corporation, Zeospan, HERCLOR manufactured by Hevcules Co., Ltd., chlorinated polyethylene [Eraslen manufactured by Showa Denko Co., Ltd .; Daisorak manufactured by Osaka Soda Kogyo Co., Ltd., manufactured by Hoechst Co., Ltd. HORTALIT
Z, DOWCPE manufactured by Dow Chemical Co., Ltd.], vinyl chloride copolymer, vinylidene chloride, polypropylene chloride, chlorinated ethylene-propylene rubber, and the like. These polymers may be used alone or in combination of two or more. .

The chlorine content of the polymer is 10 to 50% by weight, and if it is out of this range, the flexibility is impaired or the heat stability is deteriorated, and the photosensitive resin composition is too hard or colored. It is not preferable because it becomes easy. Since the conjugated diene-based hydrocarbon polymer containing a chlorine atom or its copolymer contains a carbon unsaturated bond in the main chain, there is a drawback that the chemical stability such as weather resistance is inferior to the case of only a saturated bond. Since the physical properties of the photosensitive resin composition after light irradiation greatly depend on the properties of the hydrophobic component in the present invention, it is preferable that the hydrophobic component is essentially a rubber elastic body. Therefore, its Tg
Must be 5 ° C. or lower, and particularly preferably −10 ° C. or lower.

In the present invention, not only the above-mentioned hydrophobic polymer but also an elastomer having good compatibility and ozone resistance, for example, an acrylic rubber or a polyurethane elastomer may be blended.

The content of the hydrophobic polymer in the entire composition in the present invention is 20 in consideration of the physical properties and shape retention of the printing plate.
It is preferably at least 30% by weight, and more preferably at most 80% by weight, particularly preferably at most 70% by weight, from the viewpoint of photopolymerizability.

Next, the hydrophilic polymer in the present invention means water or a polymer containing water as a main component and soluble or swelling (dispersing) in a developing solution containing an alkaline aqueous solution, an acidic aqueous solution, an organic solvent, a surfactant or the like. -CO ₂ M group, -SO ₃ M
Groups, (M is a hydrogen atom, a I, II, III group elements of the periodic table, showing amine, ammonium), - is NH _2, have a hydrophilic group such as -OH, and no crosslinking a chain-like polymer .

Examples of such hydrophilic polymers include general-purpose resins such as polyvinyl alcohol (PVA) and carboxymethyl cellulose, as well as a diene rubber obtained by copolymerizing (meth) acrylic acid and a diene compound, and a liquid polybutadiene modified with maleic anhydride. And a particularly effective skeleton is -COOM
A polymer having 50 to 50,000 equivalents / 10 ⁶ g of a group (M represents a hydrogen atom, a group I, II, or III element of the periodic table, an amine or ammonium), and the group I, II, or III element of the periodic table includes Alkali metals such as sodium, potassium, and lithium; alkaline earth metals such as calcium and magnesium; boron; and aluminum. Incidentally it is difficult to develop in neutral water poor affinity for water in -COOM groups less than 50 equivalents / 10 ⁶ g in the present invention, whereas 50,0
If it exceeds 00 equivalents / 10 ⁶ g, it is not preferable because the water-based ink resistance is inferior.

Specific examples of the hydrophilic polymer include -COOM group-containing polyurethane, -COOM group-containing polyurea urethane, -COOM group-containing polyester, -COOM group-containing epoxy compound, -COOM
Group-containing polyamic acid, -COOM group-containing acrylonitrile-
Butadiene copolymer, -COOM group-containing styrene-butadiene copolymer, -COOM group-containing polybutadiene, polyacrylamide, sodium polyacrylate, polyvinyl alcohol (PVA), carboxymethyl cellulose (C
MC), hydroxyethylcellulose (HEC), methylcellulose (MC), polyethylene oxide, polyethyleneimine, and derivatives of such compounds, but are not limited thereto.

Examples of the compound used to neutralize at least a part of the carboxyl group contained in the hydrophilic polymer include hydroxides of alkali metals such as lithium hydroxide, potassium hydroxide and sodium hydroxide, and lithium carbonate. , Potassium carbonate, sodium carbonate and other alkali metal carbonates, potassium t-butoxide, alkali metal alkoxides such as sodium methoxide, calcium hydroxide, magnesium hydroxide, polyhydric metal hydroxides such as aluminum hydroxide, aluminum Polyvalent metal alkoxides such as isopropoxide, triethylamine, tri-n-
Tertiary amines such as propylamine; secondary amines such as diethylamine and di-n-propylamine; primary amines such as ethylamine and n-propylamine; cyclic amines such as morpholine; N, N-dimethylaminoethyl (Meta)
Examples include acrylates, amino group-containing (meth) acrylates such as N, N-diethylaminoethyl (meth) acrylate, ammonium carbonate, and ammonium salts. These may be used alone or in combination of two or more.

Further, the hydrophilic polymer may have a polyoxyalkylene chain as a hydrophilic part other than the -COOM group, and may contain an ethylenically unsaturated group so as to act as a crosslinking agent.

In the present invention, in addition to the hydrophilic polymer, for example, a polymer having a hydrophilic group such as a hydroxyl group, an amino group, a sulfonic acid group and / or a polyoxyalkylene chain may be used in combination.

The content of the hydrophilic polymer in the whole composition is preferably 5 to 50% by weight, particularly preferably 5 to 40% by weight, and more preferably 7 to 20% by weight in consideration of aqueous phenomena and water-resistant ink properties. .

As the compound containing an ethylenically unsaturated group polymerizable by actinic light compounded in the present invention, as a function hydrophobic in addition to the photosensitivity, hydrophilic or hydrophobic,
It may have a hydrophilic amphoteric and contain at least one terminal ethylenic group, and this compound is capable of forming a high molecular weight polymer by free radical-initiated chain propagation addition polymerization. . Suitable ethylenically unsaturated compounds are unsaturated esters of polyols, especially such esters with α-methylene carboxylic acid, such as ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, glycerol diacrylate, 1 1,3-propanediol di (meth) acrylate, 1,4-butanediol di (meth) acrylate,
2,4-butanetriol tri (meth) acrylate, 1,4
-Cyclohexanediol di (meth) acrylate, 1,
6-hexanediol di (meth) acrylate, trimethylolpropane tri (meth) acrylate, diallyl phthalate, fumaric acid diethyl ester, maleic acid dibutyl ester and the like, and N-methylmaleimide, N-ethylmaleimide, N-lauryl N-substituted maleimide compounds such as maleimide, oligonitrile / butadiene (meth) acrylate, oligonitrile / urethane (meth) acrylate, oligourethanedi (meth)
Oligo (meth) acrylates such as acrylate, oligobutadiene di (meth) acrylate, and oligobutadiene-urethane di (meth) acrylate may be mentioned, and these may be used alone or in combination.

The content of the compound containing an ethylenically unsaturated group in the composition is preferably 1 to 50% by weight, and if it is less than 1% by weight, the photopolymerizability is hindered, so that no image remains after development. Conversely, if it is more than 50% by weight, shape retention will be impaired.
Further, the plate after light irradiation is hard and brittle, which is not preferable as a material for flexographic printing plates, which is not preferable. More preferably, it is 5 to 40% by weight.

The compound containing an ethylenically unsaturated group exists in a continuous phase or a dispersed phase due to its polarity, that is, hydrophobicity or hydrophilicity.

Next, as the photopolymerization initiator compounded in the present invention, for example, benzophenones, benzoins, acetophenones, benzyls, benzoin alkyl ethers, benzylalkyl ketals, anthraquinones,
Thioxanthones and the like. Specifically, 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 Thioxanthone, 2-chlorothioxanthone and the like. These are preferably contained in the composition in an amount of 0.01 to 5% by weight. If the amount is less than 0.01%, the photopolymerization initiation ability is impaired. If the amount is more than 5%, the curing depth cannot be obtained by the light itself, and the image tends to be chipped by development, which is not preferable. More preferably, it is 0.1 to 3% by weight.

In the present invention, in order to simply prevent thermal polymerization without suppressing the photocrosslinking reaction, a thermal polymerization inhibitor may be contained in an amount of 0.001 to 5% by weight in addition to the composition. Useful thermal polymerization inhibitors include, for example, hydroquinone, hydroquinone monoethyl ether, catechol, pt-
Butyl catechol, 2,6-di-t-phthyl-p-cresol and the like can be mentioned.

In the present invention, as a plasticizer in addition to the composition, liquid polybutadiene rubber, liquid polyacrylonitrile butadiene rubber, liquid polystyrene butadiene rubber, liquid isoprene rubber and the like, liquid rubber, polyvinyl chloride, chlorinated polyethylene, chlorinated polypropylene, , Etc., and fine powders of silica, diatomaceous earth and the like having a relatively low molecular weight.

In the printing plate of the present invention, the method for forming the phase structure as shown in FIG. 1 is not limited. For example, a preferable method includes the addition of a solvent that swells the hydrophilic polymer. That is, this is a method in which a solvent that swells and dissolves the hydrophilic polymer but has a small degree of swelling with respect to the hydrophobic polymer is added. Specific examples of such a solvent include water, water containing a surfactant, and anionic surfactants such as sodium alkyl benzene sulfonate, sodium alkyl naphthalene sulfonate, sodium alkyl ether sulfonate, and fatty acid as the surfactant. Surfactants, nonionic surfactants, cationic surfactants, lithium hydroxide, potassium hydroxide, sodium hydroxide, sodium borate, sodium carbonate, sodium acetate, water containing salts including magnesium acetate, methyl, etc. Alcohol, ethyl alcohol, propyl alcohol, isopropyl alcohol, butyl alcohol, isobutyl alcohol, t-butyl alcohol, pentyl alcohol, neopentyl alcohol, and alcohols containing the above salts, and the like can be mentioned. Can be used in combination it is. Further, solvents which can swell the hydrophilic polymer include esters, ketones and amides. Specifically, solvents including but not limited to ethyl acetate, propyl acetate, isopropyl acetate, butyl acetate, isobutyl acetate, methyl cellosolve, ethyl cellosolve, acetone, methyl ethyl ketone, methyl isobutyl ketone formamide, dimethyl formamide, dimethyl acetamide, etc. It is not something to be done. These solvents can be used alone or in combination.

The phase structure of the photosensitive resin printing plate, which is a feature of the present invention, can be easily obtained by blending the solvent for swelling the hydrophilic polymer and the solvent for swelling the hydrophobic polymer in an arbitrary ratio and performing phase separation. I can do it. In addition, as a method of forming a phase structure, fine particles having a structure in the present invention are prepared in advance by means such as emulsion polymerization, melt extrusion, mill blending and the like, and dispersed at the time of preparing the photosensitive resin composition. The present invention is not limited to these methods.

Further, as a method of preparing a printing original plate using the photosensitive resin plate composition, the respective components are swelled with a suitable solvent in an arbitrary order, for example, a hydrophobic polymer such as tetrahydrofuran, dioxane, methyl ethyl ketone, toluene cyclohexanone, and chloroform. Solvent and water,
Dissolving and mixing in a solvent that swells, dissolves, and disperses hydrophilic polymers such as alcohols, removes the solvent to some extent, and heats and presses on a suitable support, for example, a film of polyester, polyethylene, or polypropylene. Can be created. A similar film or a film coated or laminated with a thin layer of polyvinyl alcohol, polyacrylamide, hydroxypropyl cellulose or the like soluble in an aqueous developer may be provided on a surface different from the support.

The ultraviolet light used for curing the photosensitive resin plate obtained by the method is a wavelength of 150 to 500 mμ, particularly 300 to
It is effective in the wavelength region of 400mμ, and the light source used is a low-pressure mercury lamp, high-pressure mercury lamp, carbon arc lamp,
Ultraviolet fluorescent lamps, chemical lamps, xenon lamps, and zirconium lamps are desirable. The photosensitive resin printing plate of the present invention is prepared by irradiating a negative film having a transparent image with the above light source and irradiating the image with ultraviolet rays and exposing the non-image portion which is not exposed using a developing solution. Is obtained.

As the developer, pH 5.0 to 9.0 containing water for daily use in general
Is most suitable, and may contain an alkaline compound such as sodium hydroxide or sodium carbonate, a surfactant, a water-soluble organic solvent, or the like as a main component of the water. As the above-mentioned surfactant, sodium alkylnaphthalenesulfonate, sodium alkylbenzenesulfonate and the like are most suitable, and in addition, anionic surfactants, nonionic surfactants, cationic surfactants, and amphoteric surfactants are preferable. Can be used.

 The developer is preferably used at a temperature of 25 ° C to 45 ° C.

The photosensitive resin printing plate of the present invention has rubber elasticity and is useful as a flexographic printing plate. In addition, it has excellent ink resistance, ink transferability and printing durability. In addition, the photosensitive resin composition used in the present invention is mainly useful as a flexographic printing plate, but can also be applied to photoresists, sandplasts, and other applications as an elastomer which is cured by ultraviolet rays, such as adhesion. It can also be used for agents, films, paints and others.

(Operation) A feature of the printing plate of the present invention is that particles having a phase mainly composed of a hydrophobic polymer and a phase mainly composed of a hydrophilic polymer are used as a dispersed phase, and a phase having a hydrophilic component and a hydrophobic component is used as a dispersed phase. Examples of the phase structure include a continuous phase. During development, the phase mainly composed of the hydrophilic polymer in the continuous phase and the dispersed phase particles is swelled and dispersed by water absorption, and mainly composed of the hydrophobic polymer of the dispersed phase. Disperse the phases. According to this mechanism, water development is possible even when the content of the hydrophobic polymer is increased and the content of the hydrophilic polymer is reduced, and therefore the content of the hydrophilic component can be reduced. Is expected to be improved.

(Examples) Hereinafter, the present invention will be described specifically with reference to examples, but the present invention is not limited to these examples.

 In the examples, “parts” means “parts by weight”.

The hardness, rebound resilience and phase structure of the printing plate of the present invention were confirmed by the following methods.

Hardness: Measured at 20 ° C. by a spring-type hardness test (A type) method according to JIS-K6301.

Rebound resilience: 20 steel balls of φ10m / m (weight 4.16g)
The height (a), which was dropped from the height of the cm ground and bounced back, was read and displayed as (a / 20) × 100%.

Confirmation of the phase structure: obtained relief created sections of 2μm in cryomicrotome (Lai Heldt Ultracut N) at the -60 ° C., by staining with vapor of O _s S _4, only the hydrophobic polymer is dyed FT-IR microscopy (BIOLAD Digilab FTS-40)
/ UMA-300).

Alternatively, by immersing the obtained relief in a 1.0% aqueous solution of primocyanin (crystal violet) at 25 ° C. for 30 minutes, the hydrophilic polymer is selectively stained, and a 2 μm section is cut with a cryomicrotome (Reichert Ultracut N). It was prepared and observed with a reflection microscope.

Example 1 21.8 parts of hexamethylene diisocyanate, 15.4 parts of dimethylolpropionic acid, 7.6 parts of polytetramethylene glycol (PG-100 manufactured by Nippon Polyurethane Industry Co., Ltd.), and 1.0 part of di-n-butyltin dilaurate in 300 parts of tetrahydrofuran Dissolve the solution with a stirrer
The flask was placed in a flask, and the flask was heated to 65 ° C. while stirring, and the reaction was continued for 3 hours. In a separate container, acrylonitrile-butadiene oligomer containing terminal amino groups (Hycar AT
A solution prepared by dissolving 55.3 parts of BNX 1300 × 16 (produced by Ube Industries, Ltd.) in 100 parts of methyl ethyl ketone was added to the above one flask while stirring at room temperature. The obtained polymer solution was dried under reduced pressure to remove tetrahydrofuran and methyl ethyl ketone to obtain a polymer having a number average molecular weight of 21,000. Next, 100 parts of the polymer was treated with 100 parts of methyl ethyl ketone.
A solution prepared by dissolving 4.8 parts of lithium hydroxide in 100 parts of methyl alcohol was added to the solution dissolved in 100 parts of the solution while stirring at room temperature, and further stirred for 30 minutes to obtain a hydrophilic polymer [I].

10 parts of the above hydrophilic polymer [I] and chlorinated polyethylene (H-135 Osaka Soda Co., Ltd.) as the hydrophobic polymer
45 parts, styrene / butadiene rubber (SBR1507 manufactured by Nippon Synthetic Rubber Co., Ltd.) 15 parts, butadiene oligoacrylate (PB-A Kyoeisha Yushi Co., Ltd.) 28.5 parts, benzyldimethylketanol (Irgacure 651, Ciba Geigy)
1 part) and hydroquinone monomethyl ether 0.5
Toluene 40 parts, dissolved in water 10 parts, dispersed, kneaded at 105 ° C. using a heating kneader and defoamed, the resulting photosensitive resin composition at 105 ° C., 100 kg / cm ^{3 in} a heat press machine Pressure is applied between a polyester film having a thickness of 125 μm and a polyester film having the same polyester film coated with 2 μm of polyvinyl alcohol on one side so that the polyvinyl alcohol coat layer is heated and pressed for 1 minute so that the photosensitive resin is in contact with the polyester film. mm sheet was made.

The top layer of polyester film is peeled off to leave a polyvinyl alcohol film on the photosensitive resin layer, and a negative film having an image is adhered on top of it, and a mercury lamp (manufactured by Dainippon Screen Co., Ltd.) is used to illuminate 25 W / m ² , Exposure was performed for 5 minutes. After removing the negative film, development was carried out with a brush at 40 ° C. for 15 minutes in neutral water containing 2% by weight of sodium alkylnaphthalenesulfonate. As a result, an image pattern having a relief depth of 1.2 mm was obtained. This image pattern faithfully reproduced the image of the negative film used. Further, the obtained relief had a good transferability of the ink and showed a clear image.

Obtained relief created sections of 2μm in cryomicrotome (Lai Heldt Ultracut N) at the -60 ℃, O _{s S 4} steam stained, and observed by the reflection type microscope, phase structure the FT-IR microscopy (BIOLAD Digilab FTS-40 / UMA-30
The local composition was analyzed at 0).

Only chlorine polyethylene, which is a hydrophobic component, was not dyed in each composition but contained a hydrophilic component, and other components containing a butadiene component were dyed.

The dispersed phase has a particle size of 10 to several tens of μm,
m and a non-stained phase. In addition, the continuous phase was stained. According to IR analysis, both the dispersed phase and the continuous phase contain a hydrophobic component, chlorinated polyethylene, and a butadiene component containing a hydrophilic component, but the continuous phase has a higher content of butadiene component than the dispersed phase. It has been shown.

The obtained relief is immersed in a 1.0% aqueous solution of primocyanin (crystal violet) at 25 ° C. for 30 minutes,
Cryomicrotome (Reichert Ultra Cut N)
A 2 μm section was prepared using the above method and observed with a reflection microscope. Hydrophilic polymer [I] of each composition is selectively stained, within a portion of the particles having a year O _s S ₄ stained the same order of magnitude, be ambient and the continuous phase is dyed shown Was done.

Example 2 A relief pattern was obtained in the same manner as in Example 1 except that 4.56 parts of sodium hydroxide was used instead of 4.8 parts of lithium hydroxide in the hydrophilic polymer [I] of Example 1, and an image of a negative film was obtained. Was faithfully reproduced, and a relief having excellent ink transferability was obtained.

The stained similarly by O _s S ₄ and crystal violet as in Example 1, the same phase structure as in Example 1 and examined microscopically were observed.

Example 3 A relief pattern was obtained in the same manner as in Example 1 except that 17.9 parts of N, N-dimethylethyl methacrylate was used in place of 4.8 parts of lithium hydroxide in the hydrophilic polymer [I] of Example 1. The image of the negative film was faithfully reproduced, and a relief excellent in ink transferability was obtained.

The stained similarly by O _s S ₄ and crystal violet as in Example 1, the same phase structure as in Example 1 and examined microscopically were observed.

Example 4 A relief pattern was obtained in the same manner as in Example 1, except that 2.4 parts of lithium hydroxide and 6.1 parts of magnesium acetate were used instead of 4.8 parts of lithium hydroxide in the hydrophilic polymer [I] of Example 1. As a result, an image of the negative film was faithfully reproduced, and a relief excellent in ink receiving transferability was obtained.

Example 5 In the same manner as in Example 1, except that the hydrophilic polymer [I] of Example 1 was replaced by a polyisoprene containing sodium carboxyl chloride (Kurapre LIR840 Kuraray Co., Ltd.) instead of the hydrophilic polymer [I]. When a relief pattern was obtained, the image of the negative film was faithfully reproduced, and a relief excellent in ink receiving transferability was obtained.

The stained similarly by O _s S ₄ and crystal violet as in Example 1, the same phase structure as in Example 1 and examined microscopically were observed.

Example 6 A relief pattern was formed in the same manner as in Example 1 except that in place of the hydrophilic biopolymer [I], a nitrile-butadiene rubber containing sodium chloride and a carboxyl group (NIPOL 1072 Nippon Zeon Co., Ltd.) was used. As a result, a negative film image was faithfully reproduced, and a relief excellent in ink receiving transferability was obtained.

The stained similarly by O _s S ₄ and crystal violet as in Example 1, the same phase structure as in Example 1 and examined microscopically were observed.

Example 7 A relief pattern was prepared in the same manner as in Example 1 except that styrene-butadiene (SN-307 Sumitomo Nogatack Co., Ltd.) containing a sodium chloride carboxyl group was used in place of the hydrophilic biopolymer [I]. As a result, the image of the negative film was faithfully reproduced, and a relief having excellent ink transferability was obtained.

The stained similarly by O _s S ₄ and crystal violet as in Example 1, the same phase structure as in Example 1 and examined microscopically were observed.

Example 8 In Example 1, epichlorohydrin rubber (Epichromer H Osaka Soda Co., Ltd.) was used instead of chlorinated polyethylene.
When a relief pattern was obtained in the same manner as in Example 1 except that the negative pattern was used, an image of a negative film was faithfully reproduced, and a relief having excellent ink transferability was obtained.

The stained similarly by O _s S ₄ and crystal violet as in Example 1, the same phase structure as in Example 1 and examined microscopically were observed.

Example 9 A relief pattern was obtained in the same manner as in Example 1 except that a styrene-butadiene-styrene block copolymer (Clayton 1101 (trade name) manufactured by Shell Petrochemical Co., Ltd.) was used instead of the chlorinated polyethylene. As a result, a negative film image was faithfully reproduced, and a relief having excellent ink transferability was obtained.

The stained similarly by O _s S ₄ and crystal violet as in Example 1, the same phase structure as in Example 1 and examined microscopically were observed.

Example 10 In Example 1, 7.5 parts of hydrophilic biopolymer [I] and 47.5 parts of chlorinated polyethylene (H-135, manufactured by Osaka Soda Co., Ltd.)
Parts, styrene-butadiene rubber (SBR 1507, Nippon Rubber Co., Ltd.) 15 parts, butadiene oligoacrylate (PB-
A 28.5 parts of Kyoeisha Oil & Fat Co., Ltd., 1 part of benzyldimethyl ketal (Irgacure 651 Ciba Geigy Co., Ltd.) and 0.5 part of hydroquinone monomethyl-ether were used, and a relief pattern was obtained in the same manner as in Example 1. The image of the film was faithfully reproduced, and a relief excellent in ink receiving transferability was obtained.

The stained similarly by O _s S ₄ and crystal violet as in Example 1, the same phase structure as in Example 1 and examined microscopically were observed.

Example 11 A relief pattern was obtained in the same manner as in Example 1 except that methyl alcohol was used in place of water in Example 1, and the image of the negative film was faithfully reproduced, and the relief was excellent in ink receiving transferability. was gotten.

The stained similarly by O _s S ₄ and crystal violet as in Example 1, the same phase structure as in Example 1 and examined microscopically were observed.

Example 12 In Example 4, a relief pattern was obtained in the same manner as in Example 4 except that methyl alcohol was used instead of water. When the relief pattern was faithfully reproduced, the relief of the negative film was excellent. Obtained.

The dyed same phase structure as in Example 1 to microscopic observation by O _s S ₄ and crystal violet in the same manner as in Example 1 was observed.

Reference Example Table 1 shows the developing speed, hardness and rebound resilience of the reliefs obtained in Examples 1 to 12.

(Effects of the Invention) The printing plate of the present invention having the above-described configuration has sufficient rubber elasticity, is capable of being developed with water, and has contradictory properties such as water-based ink resistance. It is great to contribute to such things.

[Brief description of the drawings]

FIG. 1 is a schematic view showing a section of a printing plate of the present invention observed at a magnification of about 300 times with a microscope. 1 is a phase mainly composed of a hydrophobic polymer, and 2 is a phase mainly composed of a hydrophilic polymer. Are shown.

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-1-219833 (JP, A) JP-A-3-171139 (JP, A) JP-A-1-108542 (JP, A) JP-A-1- 300246 (JP, A) JP-A-3-196604 (JP, A) JP-A-2-305805 (JP, A) JP-A-63-186232 (JP, A) JP-A-2-175702 (JP, A) (58) Field surveyed (Int. Cl. ⁶ , DB name) G03F 7/00, 7/004

Claims (1)

(57) [Claims] 1. A particle comprising a phase mainly composed of a hydrophilic polymer around a phase mainly composed of a non-crosslinked hydrophobic polymer, a compound containing an ethylenically unsaturated group and a photopolymerization initiator. A photosensitive resin printing plate obtained by developing a photosensitive resin printing original plate to be developed.