JP2903840B2 - Lithographic printing plate manufacturing method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a lithographic printing plate, and more particularly, to a method for producing a water-developable positive-working photosensitive lithographic printing plate.

[0002]

2. Description of the Related Art Conventionally, a lithographic printing plate is prepared by applying a photosensitive resin on an aluminum substrate having a water-retaining surface, irradiating active energy rays such as ultraviolet rays through a negative film or the like to form a latent image, and then forming a solvent. It is manufactured by developing using a developing solution such as an alkaline aqueous solution to form an image area which repels water and receives oily ink and a non-image area which receives water and repels oily ink. However, in order to keep the aluminum substrate water-retained, its surface must be roughened by graining or an anodic oxide film must be formed. Alternatively, a planographic printing plate obtained as described above has a disadvantage that it requires a large amount of power and is considerably expensive.

In order to eliminate the above-mentioned adverse effects, a method using a water-insoluble acrylic resin layer as a hydrophilic layer (Japanese Patent Publication No. 49-2286), a water-soluble melamine resin, polyvinyl alcohol,
A method of applying a composition containing a water-insoluble inorganic powder has been proposed (JP-A-62-280766). However, even with these methods, there is still a need for a step of forming an image by further coating a photosensitive resin on the hydrophilic layer.

[0004]

SUMMARY OF THE INVENTION Accordingly, the present inventors
By providing a resin layer that satisfies water retention and photosensitivity at the same time, we conducted intensive research to easily realize water retention and image formation, and found that on a lipophilic adhesive layer provided on a plastic film or a support In addition, by providing a hydrophilic resin layer mainly composed of photosensitive microgel fine particles having a polymerizable double bond and a hydrophilic group on the surface, it is possible to easily achieve both image formation and water retention by irradiation with active energy rays. The inventors have found that the present invention can be performed, and have reached the present invention.

[0005]

That is, the present invention relates to a plastic film comprising a core comprising a lipophilic material and a shell comprising a hydrophilic material.
A hydrophilic resin layer was formed by applying and drying an aqueous dispersion mainly composed of photosensitive microgel fine particles having a polymerizable double bond and a hydrophilic group on the surface of the fine particles having a shell structure. Thereafter, a method for producing a lithographic printing plate is provided, in which the non-image portion is cured by irradiation with active energy rays, and the image portion is removed by development. Further, the present invention provides a lipophilic adhesive layer on a support, and further, on the adhesive layer, fine particles having a core / shell structure comprising a core formed of a lipophilic material and a shell formed of a hydrophilic material. After coating and drying an aqueous dispersion mainly containing photosensitive microgel fine particles having a polymerizable double bond and a hydrophilic group on the surface of the fine particles to form a hydrophilic resin layer, A method for producing a lithographic printing plate, characterized in that an image area is cured by irradiation with an active energy ray and the image area is removed by development.

A photosensitive microgel fine particle having a polymerizable double bond and a hydrophilic group on its surface, which is used for a resin layer having a hydrophilic function in a lithographic printing plate, has already been disclosed in JP-A-2-263805. As described above, the core / shell structure is adopted, and a lipophilic material is used for a core portion which occupies most of the core, and a hydrophilic material is used for a shell portion. However, since the crosslinking is carried out by irradiation with active energy rays, a lithographic printing plate having water retention, good water resistance, and hardly swelling in the solvent in the ink can be produced. The hydrophilic groups on the photosensitive microgel surface (shell part) include carboxyl groups,
Hydroxyl group, sulfonic group, sulfate group, phosphate group or their alkali metal salts, ammonium salts,
Amine salts and the like. Of these, a carboxyl group is particularly preferred. In addition, although a lipophilic material is used for the core portion, no particular problem occurs even when a hydrophilic material is used in combination within a range that does not impair the lipophilicity.

[0007] The polymerizable double bond on the surface of the photosensitive microgel fine particles is formed by utilizing the reaction between a carboxyl group and an epoxy group to form a microgel fine particle having a carboxyl group on the surface and an epoxy group and at least one It can be introduced by reacting with a compound having a polymerizable double bond. The microgel fine particles having a carboxyl group on the surface can be obtained by emulsion polymerization of a monomer having a polymerizable double bond using (A) a carboxyl group-containing polymer emulsifier, or (B) using a surfactant or the like. It can be obtained by a method such as seed polymerization of a polymerizable monomer having a carboxyl group onto polymer fine particles obtained by emulsion polymerization.

Among the monomers having a polymerizable double bond forming the core, monofunctional monomers include (a) (meth) acrylates: methyl (meth) acrylate, ethyl (meth) acrylate, and (meth) acrylate. Propyl acrylate,
(Meth) such as isopropyl (meth) acrylate, (butyl methacrylate, hexyl (meth) acrylate, octyl (meth) acrylate, lauryl (meth) acrylate, etc.
C1-C18 alkyl esters of acrylic acid: Glycidyl (meth) acrylate: C2-C20 alkenyl esters of (meth) acrylic acid such as allyl (meth) acrylate: (e.g., hydroxyethyl (meth) acrylate, hydroxypropyl (meth) acrylate) C2-C20 hydroxylalkyl esters of (meth) acrylic acid: C3-C19 alkenyloxylalkyl esters of (meth) acrylic acid such as allyloxylethyl (meth) acrylate: (b) vinyl aromatic compounds such as (meth) acrylic acid: Styrene, α-methylstyrene, vinyltoluene,
(c) Others: acrylonitrile, methacrylonitrile, methyl isopropenyl ketone: vinyl acetate, vinyl propionate, and the like.

The crosslinkable monomer having two or more polymerizable double bonds for three-dimensionally crosslinking the inside of the microgel fine particles includes (a) (meth) acrylate: trimethylolpropanetri (meth) acrylic. (B) polyolefins such as acid esters, di (meth) acrylates of glycols, di (methacrylates of polyols, di (meth) acrylates of polyurethanes, and di (meth) acrylates of polyesters Compounds: butadiene, isoprene, chloroprene,
And divinylbenzene.

[0010] These monomers are appropriately selected according to the desired physical properties, and may be used alone or in combination.
Species or more can be used in combination.
However, when a monofunctional monomer is used, the inside of the microgel fine particles is not three-dimensionally crosslinked by itself, and physical properties such as strength of a lithographic printing plate are impaired. Therefore, a crosslink having two or more polymerizable double bonds is used. It is desirable to improve the physical properties by three-dimensionally cross-linking the inside of the microgel fine particles by using in combination with a reactive monomer or using a reactive emulsifier as an emulsifier. The ratio when the monofunctional monomer and the crosslinkable monomer are used in combination is usually 100: 0.1 to 50, preferably 100: 0.1 to 30 in molar ratio.

The monomer having a polymerizable double bond is obtained by emulsion polymerization using (A) a carboxyl group-containing polymer emulsifier, or (B) emulsion polymerization using a surfactant or the like. Microgel fine particles having a carboxyl group on the surface are obtained by, for example, seed polymerizing a polymerizable monomer having a carboxyl group onto the polymer fine particles.
In the method (A), the carboxyl group-containing polymer emulsifier has an effect as an emulsifier, and usually, the carboxyl group in the carboxyl group-containing polymer compound is neutralized with an alkali metal, ammonium or the like to form a carboxylate. Is used.

Examples of the carboxyl group-containing polymer emulsifier include a homopolymer of a reaction product of a carboxyl group-containing polymerizable monomer such as acrylic acid, methacrylic acid, maleic acid, and itaconic acid with an alkali metal or ammonium, or the above-mentioned polymerizable emulsifier. A reactant of a monomer with an alkali metal or ammonium or the like and another polymerizable monomer such as methyl (meth) acrylate, ethyl (meth) acrylate,
C1-C18 alkyl esters of (meth) acrylic acid such as propyl (meth) acrylate, butyl (meth) acrylate, hexyl (meth) acrylate: glycidyl (meth)
Acrylate: C2-C8 alkenyl ester of (meth) acrylic acid such as allyl (meth) acrylate: vinyl monomer 1 selected from C3-C19 alkenyloxyl alkyl ester of (meth) acrylic acid such as allyloxylethyl acrylate And those obtained by copolymerizing at least one species. Further, by polymerizing a hydroxyl group-containing polymerizable monomer such as hydroxyethyl (meth) acrylate and a sulfonic acid group-containing polymerizable monomer such as methallyl sulfonic acid and styrene sulfonic acid, a hydroxyl group and a sulfonic acid group are added to the polymer emulsifier. And other hydrophilic groups can be introduced.

When synthesizing a polymer emulsifier, the reaction between the carboxyl group-containing polymerizable monomer and an alkali metal or ammonia may be carried out before homopolymerization or copolymerization with another vinyl monomer. Alternatively, it may be performed after copolymerization with another vinyl monomer. The polymerization initiator can be used without any particular limitation as long as it is used in ordinary emulsion polymerization. These polymer emulsifiers can be used as such or as a reactive emulsifier into which a polymerizable double bond is introduced by reacting an epoxy group such as glycidyl (meth) acrylate with a part of a carboxyl group. When a reactive emulsifier is used, it reacts with a monomer having a polymerizable double bond forming a core at the time of synthesizing microgel fine particles, so that physical properties such as strength of a lithographic printing plate can be improved. Since a polymer emulsifier can control the degree of water solubility, it is a preferable emulsifier in applications requiring water resistance.

Further, for the purpose of assisting emulsification, a nonionic or anionic low molecular surfactant may be used in combination with a high molecular emulsifier as long as physical properties such as water resistance are not impaired. As nonionic surfactants, polyoxyethylene lauryl ether, polyoxyethylene stearyl ether,
Polyoxyethylene alkyl ethers such as polyoxyethylene cetyl ether, polyoxyethylene alkyl allyl ethers such as polyoxyethylene octyl phenyl ether and polyoxyethylene nonyl phenyl ether, polyoxyethylene derivatives, oxyethylene / oxypropylene block polymers, glycerin fatty acids Esters and pooxyethylene fatty acid esters.

Examples of the anionic surfactant include sodium dodecylbenzenesulfonate, sodium dodecylsulfate, sodium dialkylsulfosuccinate, formalin condensate of naphthalenesulfonic acid, and ammonium salt of polyoxyethylene alkylphenyl ether sulfate. A monomer having a polymerizable double bond is emulsion-polymerized using the above-mentioned emulsifier to obtain an aqueous dispersion of microgel fine particles having a carboxyl group on the surface. The polymerization initiator used at the time of emulsion polymerization is not particularly limited as long as it is used at the time of ordinary emulsion polymerization.

As the surfactant in the method (B), the above-mentioned nonionic and anionic low molecular surfactants can be used alone or in combination of two or more. In the method (B), a polymer fine particle obtained by emulsion polymerization using a surfactant is used as a seed particle, and a carboxyl group-containing polymerizable monomer is seed-polymerized in the presence of the polymer particle. The polymer fine particles to be subjected to seed polymerization have a polymerization rate of less than 100%, more preferably 10 to 90%. If the polymerization rate of the polymer fine particles is 100%, the polymer fine particles and the carboxyl group-containing polymerizable monomer do not polymerize, resulting in disadvantages in physical properties such as strength.

Examples of the carboxyl group-containing polymerizable monomer include acrylic acid, methacrylic acid, maleic acid, itaconic acid, and acrylic acid esters and methacrylic acid esters of glycols such as ethylene glycol, propylene glycol and butanediol. A part or all of which is converted to an alkali metal salt or an ammonium salt is used. The method of adding the carboxyl group-containing polymerizable monomer to the polymer-particle aqueous dispersion may be any of batch addition, continuous addition by a drip method, or a combination thereof. In the step of polymerizing the carboxyl group-containing polymerizable monomer, an emulsifier may not be added at all. However, in order to maintain the polymerization stability at a high level, the above-mentioned nonionic or anionic surfactant may be added as necessary.

Regarding the polymerization initiator, any of those used in ordinary emulsion polymerization can be used for the emulsion polymerization of a monomer having a polymerizable double bond and the seed polymerization of a carboxyl group-containing polymerizable monomer. It can be used without limitation. Thus, an aqueous dispersion of microgel fine particles having a carboxyl group on the surface can be obtained.
The amount of the emulsifier used for obtaining the microgel fine particles having a carboxyl group on the surface by the method (A) or (B) is 0.1 to 0.1% based on the monomer having a polymerizable double bond.
It is 1 to 80% by weight, preferably 1 to 40% by weight.
If the amount is less than 0.1% by weight, sufficient emulsification cannot be achieved, and if it exceeds 80% by weight, the water resistance of the obtained microgel fine particles deteriorates.

The temperature during the emulsion polymerization is preferably from 50 to 95 ° C., more preferably from 65 to 80 ° C. The solid content of the monomer having a polymerizable double bond and the emulsifier is 10 to 60% by weight. , Desirably 20 to 50% by weight. Functional group density of the carboxyl groups of the microgel in ^{microparticles, 1 * 10 -4 ~1 * 10} 1 mol / g, more preferably 1
* 10 ^{-3 to 1} mol / g. Here, the functional group density refers to m of the carboxyl group contained in 1 g of the microgel fine particles.
ol number. If the functional group density of the carboxyl groups in the microgel fine particles is less than 1 * 10 ^-4 mol / g, the hydrophilicity of the lithographic printing plate is not sufficient, and 1 * 10 ¹ mo
If it is more than 1 / g, the hydrophilicity is increased, but the water absorption is too large, so that the image dimensional property is deteriorated. The particle size of the microgel fine particles having a carboxyl group on the surface obtained as described above was measured by a light scattering method.
５００500 nm.

Thereafter, a carboxyl group on the surface of the obtained microgel fine particles is reacted with an epoxy group and an epoxy group of a compound having at least one polymerizable double bond in one molecule. Introduce a double bond. Epoxy group and at least one
Examples of the compound having two polymerizable double bonds include epoxy compounds having a polymerizable double bond such as glycidyl (meth) acrylate, N-glycidyl (meth) acrylamide, glycidyl allyl ether, and 1,2-epoxy-5-hexene. And glycidyl cinnamate. These compounds are appropriately selected according to desired physical properties, and may be used alone or in combination of two or more. The epoxy compound can be reacted with the carboxyl group on the surface of the microgel fine particles in a molar ratio within a range of 100%, and the reaction ratio is appropriately selected according to various physical properties such as hydrophilicity, strength, and hardness.

The reaction is carried out by mixing the above-mentioned compound having an epoxy group and at least one polymerizable double bond with an aqueous dispersion of microgel fine particles having a carboxyl group on the surface.
The stirring is completed only by stirring for 2 hours or more at a temperature of 0 ° C to 90 ° C, preferably 60 ° C to 80 ° C. In this manner, photosensitive microgel fine particles having a carboxyl group and a polymerizable double bond introduced on the surface of the fine particles can be obtained, but the present invention has an advantage that the reaction can be performed even in an aqueous dispersion.

The microgel fine particles having a hydrophilic group and a polymerizable double bond on the surface are prepared by utilizing a reaction between a tertiary ammonium salt and an epoxy group as described in JP-A-2-263805. It can also be manufactured. In addition, an aqueous dispersion containing photosensitive microgel fine particles includes:
Monomers, oligomers, and high molecular compounds having a polymerizable double bond, or high molecular compounds without a polymerizable double bond, if necessary, for the purpose of having various functions, do not impair the original purpose. You may add in the range. The non-photosensitive microgel fine particles having a carboxyl group and a polymerizable double bond on the surface of the present invention, which are obtained during the manufacturing process and have no polymerizable double bond on the surface, also include one of these. Examples can be given. Further, additives such as an antifoaming agent, an antioxidant, and a preservative may be added as long as the intended purpose is not impaired.

The aqueous dispersion containing the photosensitive microgel fine particles produced as described above as a main component is applied to a plastic film or a lipophilic adhesive layer provided on a support and dried to form a resin layer. After the formation, the non-image portion is cured by irradiation with active energy rays such as ultraviolet rays and electron beams, and the non-image portion is removed by water development to obtain a lithographic printing plate. As the support, conventionally used aluminum plates, steel plates, polyethylene terephthalate, polyethylene naphthalate, polyethylene, polypropylene, 6-nylon, 6,6-nylon, 12-
Plastic films such as nylon, polyurethane, and vinyl chloride are exemplified. The thickness of the support is not particularly limited as long as it does not impair the purpose of lithographic printing,
Desirably, it is in the range of 50 μm to 500 μm.

The purpose of the lipophilic adhesive layer is to firmly adhere the support to the resin layer containing photosensitive microgel fine particles as a main component, and to facilitate the reception of ink during printing. Examples of the adhesive used for the adhesive layer include a combination of isocyanate / polyol, isocyanate / amines, epoxy / amines, epoxy / carboxylic acid, epoxy / imidazole and the like.

The dry coating thickness of the aqueous dispersion containing photosensitive microgel fine particles as a main component is preferably about 0.5 μm to 5 μm. The coating method is not particularly limited, and a commonly used coater or the like can be appropriately used according to the viscosity of the aqueous dispersion and the coating thickness. Irradiation with an active energy ray can be performed by a method such as irradiation of the entire surface through a positive film, or irradiation of only a non-image portion using a laser or the like. In addition, a photopolymerization initiator can be added to an aqueous dispersion containing photosensitive microgel fine particles as a main component, if necessary, for the purpose of promoting a crosslinking reaction by irradiation with active energy rays.

As the photopolymerization initiator, benzophenone,
2-hydroxy-2-methyl-1-phenylpropane-
1-one, 1- (4-isopropylphenyl) 2-hydroxy-2-methylpropan-1-one, 2-methyl-
1- [4- (methylthio) phenyl] 2-morpholinopropanone and the like. The photopolymerization initiator is used in an amount of 0.1 to 100 parts by weight of the solid content of the photosensitive microgel fine particles.
Used in the range of 10 parts by weight. After the non-image part is cured by irradiation with active energy rays, the uncured part (image part) is removed by development. The temperature of the developer during development is
The temperature can be set in the range of 5 ° C to 70 ° C, and development is performed by a spray method or the like. After development, a lithographic printing plate is produced by drying. By development, a lipophilic adhesive layer provided on the plastic film or the support appears on the surface, and ink receptivity of the image area is obtained. In addition, a cured hydrophilic resin layer is formed on the non-image portion that has not been removed, and the non-image portion has water receptivity.

[0027]

EXAMPLES Hereinafter, the present invention will be described in more detail with reference to examples. In the examples, “parts” and “%” refer to
The "parts by weight" and "% by weight" are respectively shown. (Example 1) (a) Synthesis of reactive polymer emulsifier 70 parts of acrylic acid, 2-ethylhexyl acrylate 7
0 parts and 140 parts of 2-propanol were heated to 80 ° C. in a nitrogen atmosphere with stirring in a 1 liter reaction vessel. Azobisisobutyronitrile (hereinafter AI)
BN) (1.1 parts), and kept at 80 ° C. for 2 hours.
Then, 0.3 parts of AIBN was added, and then the reaction mixture was kept at 80 ° C. for 4 hours to complete the polymerization. Then 10
A mixture of 272.2 parts of a 20% aqueous sodium hydroxide solution and 200 parts of water was added, and the mixture was heated to remove 2-propanol and water by azeotropic distillation to obtain a polymer emulsifier. After standing overnight, 13.8 parts of glycidyl methacrylate was added, and the mixture was heated to 80 ° C. in an air atmosphere and maintained for 4 hours to obtain a reactive polymer emulsifier. Thereafter, the solid content of the reactive polymer emulsifier was adjusted to 25%.

(B) Synthesis of photosensitive microgel 100 parts of dimethacrylate modified polybutadiene (R-45ACR-LC manufactured by Idemitsu Petrochemical Co., Ltd.)
40 parts of the reactive polymer emulsifier synthesized in (a) (solid content 1
0 parts) and 280 parts of deionized water were heated to 80 ° C. in a nitrogen atmosphere with stirring in a 1 liter reaction vessel. 16 parts of a 5% aqueous solution of azobisamidinopropane dihydrochloride (hereinafter referred to as AAPD) was added, and the mixture was kept at 80 ° C. for 2 hours. Next, 4 parts of a 5% AAPD aqueous solution was added, and after completion of the addition, the reaction mixture was kept at 80 ° C. for 4 hours to complete the polymerization to obtain a microgel fine particle aqueous dispersion. After leaving the obtained aqueous dispersion of microgel fine particles overnight, 6.8 parts of glycidyl methacrylate was added, heated to 80 ° C. in an air atmosphere, and maintained for 4 hours to obtain an aqueous dispersion of photosensitive microgel fine particles. . Measurement result of particle size by light scattering method is about 1
It was 80 nm.

(C) Production of a lithographic printing plate The solid content of the photosensitive microgel fine particle aqueous dispersion obtained in (b) was adjusted to 30%, and photopolymerization was carried out to 50 parts of the aqueous dispersion (solid content: 15 parts). Initiator (Darocure 29 manufactured by Merck)
59) was added to a 100 μm-thick corona-treated polyester film (hereinafter referred to as a treated PET film) so that the dry coating thickness was 2 μm. After drying in an oven at 80 ° C., ultraviolet irradiation was performed through a positive film to cure the irradiated portion.
The lithographic printing plate was obtained by washing out the uncured portion by spraying using water at 5 ° C. and drying.

Example 2 An aqueous dispersion of photosensitive microgel fine particles was obtained in the same manner as in Example 1 except that 2-ethylhexyl acrylate was used instead of the polymethadiene-modified dimethacrylate. The measurement result of the particle size of the photosensitive microgel fine particles by the light scattering method is about 110 n.
m. Then, a lithographic printing plate was obtained in the same manner as in Example 1.

Example 3 A polyester adhesive AD-335A / CAT-10 was applied on a treated PET film so as to have a dry coating thickness of 1 μm, and an aqueous dispersion of photosensitive microgel fine particles was further applied thereon. A lithographic printing plate was obtained in the same manner as in Example 1 except that the coating was performed.

Example 4 Dimethacrylate-modified polybutadiene (R-45AC manufactured by Idemitsu Petrochemical Co., Ltd.)
R-LC) 100 parts, nonionic surfactant (Emulgen 810 manufactured by Kao Corporation) 5 parts and deionized water 30
0 parts was heated to 80 ° C. under a nitrogen atmosphere while stirring in a 1 liter reaction vessel, and 16 parts of a 5% AAPD aqueous solution was added and maintained for 15 minutes to obtain an aqueous dispersion containing polymer fine particles.
The polymerization rate of the polymer fine particles was 30%. Continued
5 parts of acrylic acid (70 mol% neutralized with 10% aqueous sodium hydroxide solution) and 4 parts of 5% AAPD aqueous solution are added to the obtained polymer-particle aqueous dispersion, and after the addition is completed, the reaction mixture is brought to 80 ° C. After holding for 4 hours to complete the polymerization, an aqueous dispersion of microgel fine particles having a carboxyl group on the surface was obtained.

After leaving the obtained aqueous dispersion overnight, 8.9 parts of glycidyl methacrylate was added, the mixture was heated to 80 ° C. in an air atmosphere, and stirred for 4 hours.
An aqueous dispersion of photosensitive microge fine particles having a polymerizable double bond on the surface of the microgel fine particles was obtained. The particle size of the photosensitive microgel fine particles was about 200 as measured by the light scattering method.
μm. Next, the solid content of the photosensitive microgel fine particle aqueous dispersion was adjusted to 30%, and a photoinitiator (Darocur 29 manufactured by Merck & Co., Ltd.) was added to 50 parts (solid content: 15 parts) of the aqueous dispersion.
59), and a polyester-based adhesive AD-335A / CA was applied on a treated PET film having a thickness of 100 μm.
T-10 was applied so that the dry coating thickness was 2 μm on the adhesive layer formed by applying the dry coating thickness to 1 μm. After drying in an oven at 80 ° C., ultraviolet irradiation is performed through a positive film to cure the irradiated portion, and then the uncured portion is washed out with a spray method using 25 ° C. water and dried to perform lithography. A printing plate was obtained.

(Comparative Example 1) Acrylic acid (70% neutralized with sodium hydroxide) was modified with polymethadiene dimethacrylate (R-45ACR manufactured by Idemitsu Petrochemical Co., Ltd.).
−), A nonionic surfactant (Emulgen 810, manufactured by Kao Corporation) and deionized water were charged into a reaction vessel at the same time, and polymerization was carried out to obtain an aqueous dispersion of polymer-fine particles having no core / shell structure. Subsequently, denaturation with glycidyl methacrylate was performed. Thereafter, in the same manner as in Example 4, a lithographic printing plate was obtained. Table 1 shows the results of a printing test of the obtained lithographic printing plate. The lithographic printing plate is
First, it was immersed in water, and after the water had been applied to the hydrophilic layer, it was attached to an offset printing machine (AD-80, manufactured by Ryobi Printing Machine Co., Ltd.), and printing was performed.

[0035]

According to the method for producing a lithographic printing plate of the present invention, an image is easily formed by irradiating active energy rays by the action of a polymerizable double bond and a hydrophilic group on the surface of photosensitive microgel fine particles. And water retention can be achieved at the same time. Further, water can be used as a developer. Further, by providing the lipophilic adhesive layer on the support, the printing durability can be further improved.

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int.Cl. ⁶ , DB name) G03F 7/00

Claims (2)

(57) [Claims] 1. A lipophilic material on a plastic film .
And a shell formed from a hydrophilic material
And particles having a core / shell structure comprising:
After applying and drying an aqueous dispersion mainly composed of photosensitive microgel fine particles having a polymerizable double bond and a hydrophilic group on the surface of the resin layer to form a hydrophilic resin layer, the non-image area is exposed to active energy rays. A method for producing a lithographic printing plate, comprising curing by irradiation and removing an image portion by development. 2. A lipophilic adhesive layer is provided on a support, and a core formed of a lipophilic material and a hydrophilic material are further provided on the adhesive layer.
Core / shell structure consisting of a shell formed from the
After applying and drying an aqueous dispersion mainly composed of photosensitive microgel fine particles having a polymerizable double bond and a hydrophilic group on the surface of the fine particles, a hydrophilic resin layer is formed. A method for producing a lithographic printing plate, comprising: curing an image area by irradiation with an active energy ray; and removing the image area by development.