JP4502367B2 - Method for manufacturing cylindrical flexographic printing plate capable of laser engraving - Google Patents

Description

  The present invention provides relief image creation for flexographic printing plates, formation of patterns for surface processing such as embossing, relief image formation for printing of tiles, etc., conductors for electronic components, semiconductors, insulators, pattern formation, antireflection films for optical components , Pattern formation of functional materials such as color filters, (near) infrared cut filters, and alignment films, underlayers, light emitting layers, electron transport layers, sealing in the manufacture of display elements such as liquid crystal displays or organic electroluminescence displays The present invention relates to a photosensitive resin composition for flexographic printing original plate suitable for forming a coating film / pattern of a material layer and a cylindrical flexographic printing original plate.

  Flexographic printing used for packaging materials such as cardboard, paper containers, paper bags, flexible packaging films, wallpaper materials, decorative materials such as decorative boards, and label printing has increased its specific gravity among various printing methods. For the production of the printing plate used for this, a photosensitive resin is usually used, and a liquid resin or a solid resin plate formed into a sheet shape is used, a photomask is placed on the photosensitive resin, and the mask is used. A method of irradiating light through the substrate to cause a crosslinking reaction and then washing off the non-crosslinked portion with a developer has been used. In recent years, a thin light-absorbing layer called a black layer has been provided on the surface of a photosensitive resin, and this is irradiated with laser light to form a mask image directly on the photosensitive resin plate, and then light is irradiated through the mask to cause a crosslinking reaction. Later, a so-called flexo CTP (Computer to Plate) technology was developed in which the non-crosslinked portion of the light non-irradiated portion was washed away with a developing solution, and its adoption has been promoted due to the effect of improving the efficiency of printing plate production. However, this technique also has a limited efficiency improvement effect such as the development process remaining, and development of a technique that directly forms a relief image on a printing original plate using a laser and does not require development is required. . As the method, a method of engraving a printing original plate directly with a laser can be mentioned. Producing letterpress printing plates and stamps by this method has already been performed, and materials used therefor are also known.

Conventionally, printing is performed by fixing a sheet-shaped printing plate to the plate cylinder of a printing press. When fixing the printing plate to the plate cylinder, the printing plate is aligned, and cushion tape is applied under the printing plate. Work such as attaching was necessary, and it took a lot of time for these work. In recent years, a system has been developed that can perform printing only by forming a printing plate on a cylindrical support and mounting it on an air cylinder of a printing press.
For example, US Pat. No. 3,549,733 discloses the use of polyoxymethylene or polychloral. Further, Patent Document 1 (Japanese Patent Publication No. 10-512823 (German Patent A19625749)) describes the use of a silicone polymer or a silicone fluoropolymer. In this example, a filler such as amorphous silica is blended. is doing. However, in the inventions described in these publications, no photosensitive resin is used, and there is no description regarding a cylindrical printing original plate.

  On the other hand, Patent Document 2 (Japanese Patent No. 2846954 (US Pat. No. 5,798,202)) and Patent Document 1 (Japanese Patent No. 2846955 (US Pat. No. 5,804,353)) include SBS, SIS, SEBS and the like. It is disclosed to use a material in which a thermoplastic elastomer is mechanically, photochemically or thermochemically reinforced. However, in order to form a cylindrical printing original plate, first, a sheet having a laser engraveable layer formed on a flexible support is prepared, and this sheet is wound on the cylindrical support and fixed, or the surface is shaped. A method of forming a seamless cylindrical printing original is described. Therefore, the printing original plate is not directly formed on the cylindrical support.

  Patent Document 4 (Japanese Translation of PCT International Publication No. 2003-526697) describes a laser engraving printing original plate using a liquid photosensitive resin composition, and removes liquid residue generated in a large amount during laser engraving. I am using it. Although there is also a description regarding a laser-engravable cylindrical printing original plate, the liquid photosensitive resin composition to be used does not contain a solvent, and the polymer compound in the photosensitive resin composition is a liquid resin at 20 ° C.

Patent Document 5 (Japanese Patent Application Laid-Open No. 9-169060) discloses a method in which a photosensitive resin heated and melted on a cylindrical support is extruded using an extrusion molding apparatus and then molded by a calendar apparatus. . In order to heat and melt a photosensitive resin made of a thermoplastic elastomer used in the flexographic printing field, at least the temperature needs to be 100 ° C. or higher, and an extremely large apparatus such as an extruder is required. Moreover, it is difficult to freely control the film thickness of the molten resin extruded from a die attached to the tip of the extruder.
Japanese National Patent Publication No. 10-512823 Japanese Patent No. 2846954 Japanese Patent No. 2846955 Special table 2003-526697 gazette JP-A-9-169060

  A liquid that can easily form a cylindrical flexographic printing plate with an adjusted film thickness by directly applying a liquid photosensitive resin composition containing a volatile solvent on a cylindrical support and drying and removing the volatile solvent. It is an object of the present invention to provide a photosensitive resin composition and a cylindrical flexographic printing original plate.

The present inventors have intensively studied, a resin (a) having a polymerizable unsaturated group having a number average molecular weight of 1,000 to 300,000 at 20 ° C., and a polymerizable unsaturated group having a number average molecular weight of less than 1,000. organic compound having (b), a volatile solvent, hydrogen abstraction type photopolymerization initiator (d), a liquid photosensitive resin composition containing a disintegrating photopolymerization initiator (e), the liquid photosensitive A photosensitive resin layer having a viscosity of 10 Pa · s or more and 50 kPa · s or less at 20 ° C. is placed on a cylindrical support to form a photosensitive resin layer, and then the photosensitive resin layer formed in a cylindrical shape It was found that the above-mentioned problems can be solved by a method for producing a laser-engravable cylindrical flexographic printing original plate that is irradiated with light in the atmosphere to be crosslinked and cured to form a photosensitive resin cured product layer, and the present invention has been completed. It was.

The present invention is as follows.
1. Solid resin (a) at 20 ° C. having a polymerizable unsaturated group having a number average molecular weight of 1000 or more and 300,000 or less, an organic compound (b) having a polymerizable unsaturated group having a number average molecular weight of less than 1000, and volatility solvents, hydrogen abstraction type photopolymerization initiator (d), a liquid photosensitive resin composition containing a disintegrating photopolymerization initiator (e), the viscosity of the liquid photosensitive resin composition is 20 ° C. A photosensitive resin composition of 10 Pa · s or more and 50 kPa · s or less is placed on a cylindrical support to form a photosensitive resin layer, and then the photosensitive resin layer formed in a cylindrical shape is irradiated with light in the air to crosslink. A method for producing a laser-engravable cylindrical flexographic printing plate that is cured to form a cured photosensitive resin layer .
2. 1. The softening temperature of the resin (a) is 350 ° C. or less. A method for producing a cylindrical flexographic printing plate capable of laser engraving as described in 1.
3. 1. The resin (a) is a thermoplastic elastomer. 2. A method for producing a cylindrical flexographic printing original plate capable of laser engraving according to any one of the above .

4. The hydrogen abstraction type photopolymerization initiator (d) comprises at least one compound selected from benzophenones, xanthenes and anthraquinones, and the decay type photopolymerization initiator (e) comprises benzoin alkyl ethers, 2, 1. It consists of at least one compound selected from 2-dialkoxy-2-phenylacetophenones, acyloxime esters, azo compounds, organic sulfur compounds, and diketones . ~ 3 . The method for producing a cylindrical flexographic printing original plate capable of laser engraving according to any one of the above .

5 . The photosensitive resin composition further contains an inorganic porous body (f), the specific surface area of the inorganic porous body (f) is 10 m ² / g or more and 1500 m ² / g or less, and the average pore diameter is 1 nm or more and 1000 nm or less. The pore volume is 0.1 ml / g or more and 10 ml / g or less, and the oil absorption is 10 ml / 100 g or more and 2000 ml / 100 g or less. To 4 . A method for producing a cylindrical flexographic printing original plate capable of laser engraving according to any one of the above.
6 . The inorganic porous body (f) has a number average particle size of 0.1 μm or more and 100 μm or less, and at least 70% of the particles are spherical particles having a sphericity of 0.5 to 1. 5 . A method for producing a cylindrical flexographic printing plate capable of laser engraving as described in 1.
7 . Between the step of placing the photosensitive resin composition on a cylindrical support and providing a photosensitive resin layer, and the step of irradiating the photosensitive resin composition formed in a cylindrical shape with light in the air to cure by crosslinking. And 1. a step of drying and removing the volatile solvent . ~ 6. A method for producing a cylindrical flexographic printing original plate capable of laser engraving according to any one of the above .

8 . It includes 450nm or less light than the wavelength 200nm to light irradiated to the photosensitive resin layer formed into a cylindrical shape, and the illuminance on the plate surface of the light used for photo-crosslinking curing of the photosensitive resin composition, ORC Manufacturing If company made of UV Gauge "UV-M02" and (R) was measured using a UV-35-APR filter, it is 20 mW / cm ² or more and measured using the UV meter and UV-25 filter In this case, it is 5 mW / cm ² or more . ~ 7. The method for producing a cylindrical flexographic printing original plate capable of laser engraving according to any one of the above .

9 . 1. ~ 8. Including a step of forming a concave pattern by irradiating a laser beam onto a printing original plate obtained by the method for manufacturing a cylindrical flexographic printing original plate capable of laser engraving according to any one of the above, and removing the laser irradiation portion A method for producing a cylindrical flexographic printing plate formed by laser engraving.
10 . The method of manufacturing a record Za engravable cylindrical flexographic printing plate, after the step of forming a concave pattern by engraving the printing plate is irradiated with a laser beam, a step of washing away the debris generated during engraving, Thereafter, wavelength the 450nm light below or 200 nm, characterized in that it comprises a step of irradiating the printing plate surface to form a pattern 9. A method for producing a cylindrical flexographic printing plate according to 1.

  According to the present invention, a liquid photosensitive resin composition containing a volatile solvent is directly applied onto a cylindrical support, and the cylindrical flexographic printing plate can be easily formed by drying and removing the volatile solvent. The resin composition and the cylindrical flexographic printing original plate can be provided.

Hereinafter, preferred embodiments of the present invention will be described in more detail.
The cylindrical printing original plate of the present invention is composed of a cylindrical support or a structure in which a photosensitive resin layer is laminated on a cylindrical support, preferably a laminate in which a cushion layer is formed. The laminated photosensitive resin layer can be formed into a concavo-convex pattern using a general photoengraving technique, and the photosensitive resin cured product layer obtained by photocuring the entire photosensitive resin layer is irradiated with laser light. Then, the concave / convex pattern can be formed by using a laser engraving technique in which the resin in the irradiated portion is removed. General photoengraving technology means that the photosensitive resin layer is irradiated with light through an exposure mask and light-cured on the exposed portion, followed by a development step that removes the uncured portion, and then a concavo-convex pattern. Is a technology to form In the exposure process, the negative mask can be adhered to the photosensitive resin layer and irradiated with light, and as a recent technology, a black layer that can be ablated with a near infrared laser is laminated on the photosensitive resin layer, A method for producing an exposure mask by irradiating light and removing only the irradiated portion can also be applied. Furthermore, the irradiation part can be cured by scanning with ultraviolet laser light, and a cured pattern can be formed without using an exposure mask. In the development step, a developing solution in which the uncured portion is dissolved or dispersed can be used to remove the uncured portion, or a heat development method in which the uncured portion is melted by heat and absorbed and removed with a nonwoven fabric.

In the printing original plate of the present invention, when the photosensitive resin cured product layer obtained by photocuring the photosensitive resin layer is directly engraved using a laser beam to form a concavo-convex pattern, the portion of the resin irradiated with the laser beam is Removed to form a recess.
The resin (a) of the present invention preferably has a polymerizable unsaturated group having a number average molecular weight of 1,000 to 300,000 and is solid at 20 ° C. A more preferable range of the number average molecular weight of the resin (a) is 2000 or more and 200,000 or less, and a more preferable range is 5000 or more and 100,000 or less. If the number average molecular weight of the resin (a) is 1000 or more, the printing original plate produced by crosslinking later maintains strength, and the relief image produced from this original plate is strong, and when used as a printing plate, it can be used repeatedly. I can bear it. Further, if the number average molecular weight of the resin (a) is 300,000 or less, the viscosity at the time of molding of the photosensitive resin composition does not increase excessively, and a sheet-shaped or cylindrical laser engraving printing original plate is prepared. Can be produced. The number average molecular weight referred to here is a value measured by gel permeation chromatography, calibrated with polystyrene having a known molecular weight, and converted.

  The definition of “polymerizable unsaturated group” in the present invention is a polymerizable unsaturated group involved in a radical or addition polymerization reaction. Preferable examples of the polymerizable unsaturated group involved in the radical polymerization reaction include a vinyl group, an acetylene group, an acrylic group, and a methacryl group. Preferred examples of the polymerizable unsaturated group involved in the addition polymerization reaction include cinnamoyl group, thiol group, azide group, epoxy group that undergoes ring-opening addition reaction, oxetane group, cyclic ester group, dioxirane group, spiroorthocarbonate group, spiro An ortho ester group, a bicyclo ortho ester group, a cyclic imino ether group and the like can be mentioned.

  Particularly preferred are polymers having an average of 0.7 or more polymerizable unsaturated groups per molecule. When the average is 0.7 or more per molecule, the printing original plate obtained from the resin composition of the present invention is excellent in mechanical strength, and the relief shape is difficult to collapse during laser engraving. Furthermore, its durability is good, and it can withstand repeated use, which is preferable. Considering the mechanical strength of the printing original plate, the polymerizable unsaturated group of the resin (a) is preferably 0.7 or more per molecule, and more preferably more than 1. In the resin (a) of the present invention, the position of the polymerizable unsaturated group is preferably directly bonded to the end of the polymer main chain, the end of the polymer side chain, the polymer main chain, or the side chain. . The average number of polymerizable unsaturated groups contained in one molecule of the resin (a) can be obtained by a molecular structure analysis method using a nuclear magnetic resonance spectrum method (NMR method).

  As a method for producing the resin (a), for example, a direct introduction of a polymerizable unsaturated group may be used. Alternatively, a hydroxyl group, an amino group, an epoxy group, a carboxyl group, Can bind to the reactive groups of the above components having a molecular weight of about several thousand having a plurality of reactive groups such as acid anhydride groups, ketone groups, hydrazine residues, isocyanate groups, isothiocyanate groups, cyclic carbonate groups, and alkoxycarbonyl groups. A group that reacts with a terminal binding group after reacting with a binder having a plurality of groups (for example, polyisocyanate in the case of a hydroxyl group or an amino group), adjusting the molecular weight and converting to a terminal binding group And a method of introducing a polymerizable unsaturated group at the terminal by reacting with an organic compound having a polymerizable unsaturated group.

  In particular, the resin (a) used when forming a cylindrical flexographic printing original plate capable of laser engraving is preferably a resin that is easily liquefied or easily decomposed. Examples of resins that are easily decomposed include styrene, α-methylstyrene, α-methoxystyrene, acrylic esters, methacrylic esters, ester compounds, ether compounds, nitro compounds, carbonates as monomer units that are easily decomposed in the molecular chain. Preferably, compounds, carbamoyl compounds, hemiacetal ester compounds, oxyethylene compounds, aliphatic cyclic compounds, and the like are included. Especially polyethers such as polyethylene glycol, polypropylene glycol, polytetraethylene glycol, aliphatic polycarbonates, aliphatic carbamates, polymethyl methacrylate, polystyrene, nitrocellulose, polyoxyethylene, polynorbornene, polycyclohexadiene hydrogenated product Alternatively, a polymer having a molecular structure such as a dendrimer having many branched structures is a representative example of those that are easily decomposed. A polymer containing a large number of oxygen atoms in the molecular chain is preferred from the viewpoint of degradability. Among these, a compound having a carbonate group, a carbamate group, and a methacryl group in the polymer main chain is preferable because of its high thermal decomposability. For example, polyesters and polyurethanes synthesized from (poly) carbonate diol and (poly) carbonate dicarboxylic acid as raw materials, polyamides synthesized from (poly) carbonate diamine as raw materials, and the like can be cited as examples of polymers having good thermal decomposability. . These polymer main chains and side chains may contain a polymerizable unsaturated group. In particular, when a reactive functional group such as a hydroxyl group, an amino group, or a carboxyl group is present at the terminal, it is easy to introduce a polymerizable unsaturated group at the terminal of the main chain.

As the resin (a) used in the present invention, a thermoplastic elastomer can be mentioned as a preferred example, particularly when used for applications requiring rubber elasticity. For example, a copolymer of butadiene and styrene, a copolymer of isoprene and styrene, a styrene-diene-styrene triblock copolymer, and the like are preferable. Specifically, polystyrene-polybutadiene-polystyrene (SBS), polystyrene-poly Examples include isoprene-polystyrene (SIS) and polystyrene-poly (ethylenebutylene) -polystyrene (SEBS). Also, a hydrogenated product in which a part of the diene portion of the thermoplastic elastomer is replaced with hydrogen can be used. In particular, the softening temperature is preferably 350 ° C. or lower, more preferably 250 ° C. or lower, still more preferably 200 ° C. or lower. The measurement of the softening temperature of the present invention is defined by the first temperature at which the viscosity changes greatly (the slope of the viscosity curve changes) when the temperature is increased from room temperature using a dynamic viscoelasticity measuring device. To do.
In addition, examples of the rubber polymer compound include isoprene rubber, butadiene rubber, 1,2-polybutadiene rubber, styrene-butadiene rubber (SBR), nitrile rubber, butyl rubber, and ethylene-propylene rubber.

  Moreover, the compound which has a polymerizable unsaturated group in molecular principal chains or side chains, such as polydienes, such as polybutadiene and polyisoprene, can be mentioned. In addition, a polymer compound having a polymerizable unsaturated group introduced into the molecule by a chemical reaction such as a substitution reaction, elimination reaction, condensation reaction, or addition reaction using a polymer compound having no polymerizable unsaturated group as a starting material. It can also be mentioned. Examples of polymer compounds having no polymerizable unsaturated groups include polyolefins such as polyethylene and polypropylene, polyhaloolefins such as polyvinyl chloride and polyvinylidene chloride, polystyrene, polyacrylonitrile, polyvinyl alcohol, polyvinyl acetate, polyvinyl acetal, poly In addition to CC chain polymers such as acrylic acid, poly (meth) acrylic esters, poly (meth) acrylamide, and polyvinyl ether, polyethers such as polyphenylene ether, polythioethers such as polyphenylene thioether, and polyesters such as polyethylene terephthalate , Polycarbonate, polyacetal, polyurethane, polyamide, polyurea, polyimide, polydialkylsiloxane and other polymer compounds, or the main chain of these polymer compounds It may be mentioned a polymer compound having a hetero atom, a random copolymer synthesized from a plurality of types of monomer components, a block copolymer. Furthermore, it is possible to use a mixture of a plurality of polymer compounds having a polymerizable unsaturated group introduced in the molecule.

  In particular, when a flexible relief image is required as in flexographic printing plate applications, the resin (a) is partially a liquid resin having a glass transition temperature of 20 ° C. or lower, more preferably a liquid having a glass transition temperature of 0 ° C. or lower. It is particularly preferable to use a resin. Examples of such a liquid resin include hydrocarbons such as polyethylene, polybutadiene, hydrogenated polybutadiene, polyisoprene, and hydrogenated poisoprene, polyesters such as adipate and polycaprolactone, and polymers such as polyethylene glycol, polypropylene glycol, and polytetramethylene glycol. Synthesized by using ethers, aliphatic polycarbonates, silicones such as polydimethylsiloxane, polymers of (meth) acrylic acid and / or derivatives thereof, and mixtures and copolymers thereof. The compound which has can be used. The content is preferably 30 wt% or more based on the entire resin (a). In particular, unsaturated polyurethanes having a polycarbonate structure are preferred from the viewpoint of weather resistance. The liquid resin here means a polymer that has the property of being easily deformed by flow and solidified into a deformed shape by cooling. When an external force is applied, the liquid resin is instantly deformed according to the external force. When the external force is removed, the term corresponds to an elastomer having a property of restoring the original shape in a short time. The photosensitive resin composition of the present invention capable of obtaining good thickness accuracy and dimensional accuracy when the relief image forming original plate obtained from this is formed into a cylindrical shape, preferably has a viscosity at 20 ° C. of 10 Pa · s or more. 50 kPa · s or less. More preferably, it is 50 Pa · s or more and 20 kPa · s or less, and further preferably 100 Pa · s or more and 10 kPa · s or less. If the viscosity is 10 Pa · s or more, the mechanical strength of the produced printing original plate is sufficient, and the shape can be easily maintained and processed even when it is formed into a cylindrical printing original plate. When the viscosity is 50 kPa · s or less, it is easily deformed even at room temperature and is easy to process. When forming a liquid photosensitive resin layer on a cylindrical support, the photosensitive resin composition is dripped by gravity. It is desirable that the photosensitive resin composition has a relatively high viscosity so as not to cause such a phenomenon. Moreover, it is preferable that the photosensitive resin composition used by this invention has thixotropic property.

  The organic compound (b) of the present invention is a compound having a polymerizable unsaturated group having a number average molecular weight of less than 1,000. The number average molecular weight is preferably 1000 or less because of easy dilution with the resin (a). The definition of a polymerizable unsaturated group is a polymerizable unsaturated group that participates in a radical or addition polymerization reaction as described in the section of the resin (a).

  Specific examples of the organic compound (b) include radical reactive compounds such as olefins such as ethylene, propylene, styrene and divinylbenzene, acetylenes, (meth) acrylic acid and derivatives thereof, haloolefins, acrylonitrile and the like. Saturated nitriles, (meth) acrylamide and derivatives thereof, aryl compounds such as aryl alcohol and aryl isocyanate, unsaturated dicarboxylic acids such as maleic anhydride, maleic acid and fumaric acid and derivatives thereof, vinyl acetates, N-vinylpyrrolidone, N-vinyl carbazole and the like can be mentioned, and (meth) acrylic acid and derivatives thereof are preferable examples from the viewpoints of the abundance of the types, price, decomposability upon laser light irradiation, and the like. Examples of the derivative of the compound include alicyclic such as cycloalkyl-, bicycloalkyl-, cycloalkene-, bicycloalkene-, aromatic such as benzyl-, phenyl-, phenoxy-, fluorene-, alkyl-, halogen Alkyl-, alkoxyalkyl-, hydroxyalkyl-, aminoalkyl-, tetrahydrofurfuryl-, allyl-, glycidyl-, alkylene glycol-, polyoxyalkylene glycol-, (alkyl / allyloxy) polyalkylene glycol- and trimethylolpropane Examples thereof include esters of polyhydric alcohols such as polydimethylsiloxane and compounds having a polysiloxane structure such as polydiethylsiloxane. Moreover, you may be a heteroaromatic compound containing elements, such as nitrogen and sulfur.

  In addition, as a compound having an epoxy group that undergoes a ring-opening addition reaction, a compound obtained by reacting a polyol such as various diols or triols with epichlorohydrin, an epoxy compound obtained by reacting a peracid with an ethylene bond in the molecule, etc. Can be mentioned. Specifically, ethylene glycol diglycidyl ether, diethylene glycol diglycidyl ether, triethylene glycol diglycidyl ether, tetraethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, tripropylene glycol diglycidyl ether, polypropylene Glycol diglycidyl ether, neopentyl glycol diglycidyl ether, 1,6-hexanediol diglycidyl ether, glycerin diglycidyl ether, glycerin triglycidyl ether, trimethylolpropane triglycidyl ether, bisphenol A diglycidyl ether, hydrogenated bisphenol A Diglycidyl ether, bisphenol A Diglycidyl ether, polytetramethylene glycol diglycidyl ether, poly (propylene glycol adipate) diol diglycidyl ether, poly (ethylene glycol adipate) diol diglycidyl ether, poly (caprolactone) diol di of compounds with addition of lenoxide or propylene oxide Examples thereof include epoxy compounds such as glycidyl ether and epoxy-modified silicone oil (trade name “HF-105” manufactured by Shin-Etsu Chemical Co., Ltd.).

In this invention, the organic compound (b) which has these polymerizable unsaturated groups can select the 1 type (s) or 2 or more types according to the objective. For example, when used as a printing plate, it has at least one long-chain aliphatic, alicyclic or aromatic derivative as an organic compound used to suppress swelling with respect to an organic solvent such as alcohol or ester which is a solvent for printing ink. Is preferred.
In order to increase the mechanical strength of the printing original plate obtained from the resin composition of the present invention, the organic compound (b) preferably has at least one alicyclic or aromatic derivative. In this case, the organic compound It is preferable that it is 20 wt% or more of the whole quantity of (b), More preferably, it is 50 wt% or more. The aromatic derivative may be an aromatic compound having an element such as nitrogen or sulfur.

In order to increase the rebound resilience of the printing plate, for example, a methacrylic monomer as described in JP-A-7-239548 can be used, or it can be selected using the technical knowledge of known photosensitive resins for printing.
Hydrogen atom in which resin (a) or organic compound (b) is directly bonded to a sulfur atom such as thiol, a compound having a hydrogen atom that is in the α position with respect to an oxygen atom or nitrogen atom present in the molecular chain It is preferable to contain at least 20 wt% or more of the compound having a weight of the total amount of the photosensitive resin composition. More preferably, it is 40 wt% or more. Examples of the atomic group derived from the oxygen atom include alcohols, ethers, esters, and carbonates, and examples of the atomic group derived from the nitrogen atom include urethane, urea, and amide.

  Although the volatile solvent used by this invention is not specifically limited, Preferably a boiling point is 60 to 200 degreeC, More preferably, it is 70 to 150 degreeC, More preferably, it is 80 to 130 degreeC. When the boiling point of the solvent is in the range of 60 ° C. or more and 200 ° C. or less, the photosensitive resin composition can be stably applied to the cylindrical support without being excessively volatilized during the application. The solvent can be efficiently removed from the photosensitive resin composition layer. Moreover, the content rate of a solvent becomes like this. Preferably it is 5 to 60 wt% of the whole photosensitive resin composition, More preferably, it is 10 to 50 wt%, More preferably, it is 10 to 40 wt%. If it is this range, it can apply | coat stably to a comparatively thick film, without significantly reducing the viscosity of the photosensitive resin composition, and the generation | occurrence | production of the bubble in the process of removing a solvent, etc. is suppressed. Moreover, the solvent does not need to be single, and several types can be mixed and used. Although not particularly limited, for example, aromatic hydrocarbon solvents such as xylene and toluene, ester solvents such as ethyl acetate and ethyl benzoate, ketone solvents such as methyl ethyl ketone, ether solvents such as tetrahydrofuran, n- Examples include methylpyrrolidone and dimethylformamide.

  The photosensitive resin composition of the present invention is crosslinked by irradiation with light or an electron beam to develop physical properties as a printing plate, and a photopolymerization initiator can be added at that time. The photopolymerization initiator can be selected from commonly used ones. For example, radical polymerization, cationic polymerization, and anion polymerization illustrated in “Polymer Data Handbook-Fundamentals” edited by the Society of Polymer Sciences, published in 1986 by Fufukan. An agent can be used. In addition, crosslinking by photopolymerization using a photopolymerization initiator is useful as a method for producing a printing original plate with good productivity while maintaining the storage stability of the resin composition of the present invention, and is used in that case. Known initiators can also be used. As photopolymerization initiators that induce radical polymerization reactions, hydrogen abstraction type photopolymerization initiators (d) and decay type photopolymerization initiators (e) are widely used as particularly effective photopolymerization initiators.

  Although it does not specifically limit as a hydrogen abstraction type photoinitiator (d), It is preferable to use an aromatic ketone. Aromatic ketone is efficiently converted into an excited triplet state by photoexcitation, and a chemical reaction mechanism has been proposed in which this excited triplet state generates a radical by extracting hydrogen from the surrounding medium. The generated radical is considered to be involved in the photocrosslinking reaction. Any compound can be used as the hydrogen abstraction type photopolymerization initiator (d) used in the present invention as long as it is a compound that generates radicals by extracting hydrogen from the surrounding medium through an excited triplet state. Examples of aromatic ketones include benzophenones, Michler ketones, xanthenes, thioxanthones, and anthraquinones, and it is preferable to use at least one compound selected from these groups. The benzophenones refer to benzophenone or derivatives thereof, specifically 3,3 ', 4,4'-benzophenone tetracarboxylic anhydride, 3,3', 4,4'-tetramethoxybenzophenone, and the like. Michler ketones refer to Michler ketone and its derivatives. Xanthenes refer to derivatives substituted with xanthene and an alkyl group, phenyl group, or halogen group. Thioxanthones refer to thioxanthone and derivatives substituted with an alkyl group, a phenyl group, and a halogen group, and examples thereof include ethylthioxanthone, methylthioxanthone, and chlorothioxanthone. Anthraquinones are anthraquinone and derivatives substituted with alkyl groups, phenyl groups, halogen groups, and the like. The addition amount of the hydrogen abstraction type photopolymerization initiator is preferably 0.1 wt% or more and 10 wt% or less, more preferably 0.5 wt% or more and 5 wt% or less of the total amount of the photosensitive resin composition. If the addition amount is within this range, when the liquid photosensitive resin composition is photocured in the atmosphere, the curability of the cured product surface can be sufficiently secured, and the weather resistance can be secured.

  The decay type photopolymerization initiator (e) refers to a compound that generates an active radical by generating a cleavage reaction in the molecule after light absorption, and is not particularly limited. Specific examples include benzoin alkyl ethers, 2,2-dialkoxy-2-phenylacetophenones, acetophenones, acyloxime esters, azo compounds, organic sulfur compounds, diketones, and the like. It is preferable to use at least one compound selected from the group consisting of: Examples of benzoin alkyl ethers include benzoin isopropyl ether, benzoin isobutyl ether, and compounds described in “Photosensitive polymer” (Kodansha, 1977, page 228). Examples of 2,2-dialkoxy-2-phenylacetophenones include 2,2-dimethoxy-2-phenylacetophenone and 2,2-diethoxy-2-phenylacetophenone. Examples of acetophenones include acetophenone, trichloroacetophenone, 1-hydroxycyclohexylphenylacetophenone, 2,2-diethoxyacetophenone, and the like. Examples of acyl oxime esters include 1-phenyl-1,2-propanedione-2- (o-benzoyl) oxime. Examples of the azo compound include azobisisobutyronitrile, diazonium compound, and tetrazene compound. Examples of the organic sulfur compound include aromatic thiol, mono- and disulfide, thiuram sulfide, dithiocarbamate, S-acyl dithiocarbamate, thiosulfonate, sulfoxide, sulfinate, and dithiocarbonate. Examples of diketones include benzyl and methylbenzoyl formate. The addition amount of the collapsible photopolymerization initiator is preferably 0.1 wt% or more and 10 wt% or less, more preferably 0.3 wt% or more and 3 wt% or less of the total amount of the photosensitive resin composition. If the addition amount is within this range, when the photosensitive resin composition is photocured in the air, the curability inside the cured product can be sufficiently secured.

  A compound having a site functioning as a hydrogen abstraction type photopolymerization initiator and a site functioning as a decay type photopolymerization initiator in the same molecule can also be used as the photopolymerization initiator. There may be mentioned α-aminoacetophenones. Examples thereof include 2-methyl-1- (4-methylthiophenyl) -2-morpholino-propan-1-one and compounds represented by the following general formula (6).

(In the formula, each R ₂ independently represents a hydrogen atom or an alkyl group having 1 to 10 carbon atoms. X represents an alkylene group having 1 to 10 carbon atoms.)
The addition amount of the compound having a site functioning as a hydrogen abstraction type photopolymerization initiator and a site functioning as a decay type photopolymerization initiator in the same molecule is preferably 0.1 wt% or more of the total amount of the photosensitive resin composition It is 10 wt% or less, More preferably, it is 0.3 wt% or more and 3 wt% or less. When the addition amount is within this range, the mechanical properties of the cured product can be sufficiently ensured even when the photosensitive resin composition is photocured in the atmosphere.

  A photopolymerization initiator that induces an addition polymerization reaction by absorbing light and generating an acid can also be used. For example, photocationic polymerization initiators such as aromatic diazonium salts, aromatic iodonium salts, and aromatic sulfonium salts, or polymerization initiators that absorb light and generate bases. The addition amount of these photopolymerization initiators is preferably in the range of 0.1 wt% to 10 wt% of the total amount of the photosensitive resin composition.

  It is preferable to add an inorganic porous material (f) to the photosensitive resin composition of the present invention. The inorganic porous material (f) is an inorganic particle having fine pores or fine voids in the particle, and is added to absorb and remove viscous liquid residue generated in a large amount in laser engraving. It is an agent and has an effect of preventing tackiness of the plate surface. The inorganic porous material of the present invention is added for the purpose of removing viscous liquid waste, and the number average particle size, specific surface area, average pore size, pore volume, and loss on ignition greatly affect its performance. To do.

  The inorganic porous body (f) of the present invention preferably has a number average particle diameter of 0.1 to 100 μm. When a particle having a size smaller than the number average particle diameter is used, dust is likely to fly when engraving the original plate obtained from the resin composition of the present invention with a laser, the engraving apparatus is easily contaminated, and the resin (a) and organic When mixing with the compound (b), an increase in viscosity, entrainment of bubbles, generation of dust and the like are likely to occur. On the other hand, when a particle having a size larger than the above-mentioned number average particle size is used, the relief image is likely to be defective when laser engraving is performed, and the fineness of the printed matter is likely to be impaired. A more preferable range of the average particle diameter is 0.5 to 20 μm, and a further preferable range is 3 to 10 μm. The average particle size of the porous inorganic absorbent of the present invention is a value measured using a laser scattering type particle size distribution measuring device.

The range of the specific surface area of the inorganic porous material (f) of the present invention is preferably 10 m ² / g or more and 1500 m ² / g or less. A more preferable range is 100 m ² / g or more and 800 m ² / g or less. When the specific surface area is 10 m ² / g or more, removal of the liquid residue during laser engraving is sufficient, and when the specific surface area is 1500 m ² / g or less, an increase in the viscosity of the photosensitive resin composition is suppressed, and thixotropic properties are obtained. Can be suppressed. The specific surface area of this invention is calculated | required based on a BET type | formula from the adsorption isotherm of nitrogen in -196 degreeC.

  The average pore diameter of the inorganic porous material (f) of the present invention greatly affects the absorption amount of liquid residue generated during laser engraving. A preferable range of the average pore diameter is 1 nm to 1000 nm, more preferably 2 nm to 200 nm, and still more preferably 2 nm to 50 nm. If the average pore diameter is 1 nm or more, the absorbability of liquid debris generated during laser engraving can be ensured, and if it is 1000 nm or less, the specific surface area of the particles is large and the amount of liquid debris absorbed can be sufficiently ensured. When the average pore diameter is less than 1 nm, the reason why the amount of absorbed liquid debris is small is not clear, but because liquid debris is viscous, it is estimated that it is difficult to enter the micropores and the amount of absorption is small. is doing.

The average pore diameter of the present invention is a value measured using a nitrogen adsorption method. Those having an average pore diameter of 2 to 50 nm are particularly called mesopores, and the ability of porous particles having mesopores to absorb liquid waste is extremely high. The pore size distribution of the present invention is determined from the nitrogen adsorption isotherm at -196 ° C.
The pore volume of the inorganic porous material (f) of the present invention is preferably from 0.1 ml / g to 10 ml / g, more preferably from 0.2 ml / g to 5 ml / g. When the pore volume is 0.1 m / g or more, the amount of viscous liquid residue absorbed is sufficient, and when it is 10 ml / g or less, the mechanical strength of the particles can be ensured. In the present invention, a nitrogen adsorption method is used to measure the pore volume. The pore volume of the present invention is determined from an adsorption isotherm of nitrogen at −196 ° C.

As an index for evaluating the liquid residue adsorption amount of the present invention, there is an oil absorption amount. This is defined by the amount of oil absorbed by 100 g of the inorganic porous body. A preferable range of the oil absorption amount of the inorganic porous material used in the present invention is 10 ml / 100 g or more and 2000 ml / 100 g or less, more preferably 50 ml / 100 g or more and 1000 ml / 100 g or less. If the oil absorption is 10 ml / 100 g or more, the removal of liquid residue generated during laser engraving is sufficient, and if it is 2000 ml / 100 g or less, the mechanical strength of the inorganic porous body can be sufficiently secured. The oil absorption was measured according to JIS-K5101.
The inorganic porous material (f) of the present invention preferably retains its porosity without being deformed or melted by laser light irradiation in the infrared wavelength region. The loss on ignition when treated at 950 ° C. for 2 hours is preferably 15 wt% or less, more preferably 10 wt% or less.

  The particle shape of the inorganic porous material of the present invention is not particularly limited, and spherical, flat, needle-like, amorphous, or particles having protrusions on the surface can be used. In particular, spherical particles are preferable from the viewpoint of wear resistance. It is also possible to use particles having hollow inside particles, spherical granules having a uniform pore diameter such as silica sponge, and the like. Although not particularly limited, for example, porous silica, mesoporous silica, silica-zirconia porous gel, porous alumina, porous glass and the like can be mentioned. Moreover, since the pore diameter cannot be defined for a layer having a gap of several to 100 nm such as a layered clay compound, in the present invention, the gap between the layers is defined as the pore diameter.

Furthermore, organic pigments such as pigments and dyes that absorb light of the wavelength of the laser beam can be incorporated into these pores or voids.
Sphericality is defined as an index that defines spherical particles. The sphericity used in the present invention is the ratio (D ₁ / D) of the maximum value D ₁ of the circle that completely enters the projection figure when the particle is projected to the minimum value D ₂ of the circle that completely enters the projection figure. ₂ ). In the case of a true sphere, the sphericity is 1.0. The sphericity of preferable spherical particles used in the present invention is preferably 0.5 or more and 1.0 or less, more preferably 0.7 or more and 1.0 or less. If it is 0.5 or more, the wear resistance as a printing plate is good. The sphericity of 1.0 is an upper limit value of sphericity. As spherical particles, it is desirable that 70% or more, more preferably 90% or more of the particles have a sphericity of 0.5 or more. As a method of measuring the sphericity, a method of measuring based on a photograph taken using a scanning electron microscope can be used. At that time, it is preferable to take a photograph at a magnification at which at least 100 particles or more enter the monitor screen. The D ₁ and D ₂ are measured based on a photograph, but it is preferable to process the photograph using a digitizing device such as a scanner and then process the data using image analysis software.

Moreover, the surface of the inorganic porous body can be coated with a silane coupling agent, a titanium coupling agent, or other organic compounds, and subjected to a surface modification treatment to make particles more hydrophilic or hydrophobic.
In the present invention, one or two or more of these inorganic porous bodies (f) can be selected, and by adding the inorganic porous body (f), generation of liquid debris during laser engraving and relief Improvements such as tack prevention of the printing plate are effectively performed.
The ratio of the resin (a), the organic compound (b), and the inorganic porous body (f) in the photosensitive resin composition of the present invention is 5 for the organic compound (b) with respect to 100 parts by weight of the resin (a). -200 weight part is preferable and the range of 20-100 weight part is more preferable. The inorganic porous material (f) is preferably 1 to 100 parts by weight, and more preferably 2 to 50 parts by weight. A more preferable range is 2 to 20 parts by weight.

When the ratio of the organic compound (b) is smaller than the above range, it tends to cause inconveniences such as difficulty in balancing the hardness and tensile strength / elongation of the printing plate to be obtained, and when it is larger than the above range, cross-linking curing is performed. There is a tendency for the shrinkage during the process to increase and the thickness accuracy to deteriorate.
When the amount of the inorganic porous material (f) is smaller than the above range, depending on the types of the resin (a) and the organic compound (b), the generation of engraving liquid debris can be suppressed when laser engraving is performed. The effect may not be sufficiently exhibited, and if it is larger than the above range, the printing plate becomes brittle. Further, the transparency may be impaired, and particularly when used as a flexographic plate, the hardness may become too high. When a photosensitive resin composition is cured using light, particularly ultraviolet rays, to prepare a laser engraving printing original plate, light transmittance affects the curing reaction. Therefore, it is effective to use a material having a refractive index close to that of the photosensitive resin composition.

As a method of mixing the inorganic porous material in the photosensitive resin composition, a method of directly adding the inorganic porous material (f) in a state where the thermoplastic resin is heated and fluidized, or photopolymerization with the thermoplastic resin. Any method may be used in which the inorganic porous material (f) is added to the kneaded organic organic compound (b) first.
In addition, a polymerization inhibitor, an ultraviolet absorber, a dye, a pigment, a lubricant, a surfactant, a plasticizer, a fragrance, and the like can be added to the resin composition of the present invention according to the purpose and purpose.

  In the printing original plate capable of laser engraving of the present invention, the polymerizable unsaturated groups of the organic compound (b) or the polymerizable unsaturated group of the resin (a) reacts with the polymerizable unsaturated group of the organic compound (b). As a result, a three-dimensional cross-linked structure is formed and insolubilized in a commonly used ester, ketone, aromatic, ether, alcohol or halogen solvent. This reaction occurs between the organic compounds (b), between the resins (a), or between the resin (a) and the organic compound (b), and the polymerizable unsaturated group is consumed. In addition, when the photopolymerization initiator is used for crosslinking and curing, the photopolymerization initiator is decomposed by light. Therefore, the cross-linked cured product is extracted with a solvent, and mass-separated by GC-MS (gas chromatography). Analysis method), LC-MS method (method for mass spectrometry of those separated by liquid chromatography), GPC-MS method (method for separation and mass spectrometry by gel permeation chromatography), LC-NMR method (liquid chromatography) By analyzing using the method of analyzing the product separated in (1) by nuclear magnetic resonance spectrum, unreacted photopolymerization initiator and decomposition products can be identified. Furthermore, by using the GPC-MS method, LC-MS method, and GPC-NMR method, the unreacted polymer, the unreacted organic compound (b), and the polymerizable unsaturated group in the solvent extract are reacted. The resulting relatively low molecular weight product can also be identified from analysis of the solvent extract. For the high molecular weight component insoluble in the solvent in which the three-dimensional cross-linked structure is formed, by using the pyrolysis GC-MS method, the site formed by the reaction of the polymerizable unsaturated group is formed as a component constituting the high molecular weight body. It is possible to verify whether it exists. For example, it can be estimated from the mass spectrometry spectrum pattern that there is a site where a polymerizable unsaturated group such as a methacrylate group, an acrylate group, or a vinyl group has reacted. The pyrolysis GC-MS method is a method in which a sample is thermally decomposed and a generated gas component is separated by gas chromatography and then mass spectrometry is performed. The decomposition product derived from the photopolymerization initiator and the unreacted photopolymerization initiator are detected together with the unreacted polymerizable unsaturated group or the site obtained by the reaction of the polymerizable unsaturated group in the crosslinked cured product. Then, it can be concluded that the photosensitive resin composition was obtained by photocrosslinking and curing.

Identification of the organosilicon compound (c) present in the photosensitive resin composition or photocured cured product can be made by making full use of the various analytical methods described above.
Further, the amount of the inorganic porous fine particles present in the crosslinked cured product can be obtained by heating the crosslinked cured product in the air to burn off the organic component and measuring the weight of the residue. In addition, the presence of inorganic porous fine particles in the residue is due to morphological observation with a field emission type high resolution scanning electron microscope, particle size distribution with a laser scattering type particle size distribution measuring device, and nitrogen adsorption method. It can be identified from the measurement of pore volume, pore diameter distribution and specific surface area.

  In the case of the present invention, the photosensitive resin composition contains a volatile solvent, which is applied on a cylindrical support and dried to remove the solvent component. However, it seems difficult to completely remove the solvent component. is there. Therefore, the analysis of the volatile solvent component remaining in the photosensitive resin composition layer or the cured photosensitive resin layer can be quantitatively analyzed using the pyrolysis GC / MS method. In other words, since the solvent component contained in the pyrolysis gas can be separated by GC and identified by mass spectrometry, the solvent component having a known weight is analyzed by the same method for the identified solvent component. By comparing the peak intensities, the amount of the residence solvent contained in the photosensitive resin composition layer or the cured photosensitive resin layer can be known. There is a tendency that the concentration of the solvent remaining inside is higher than the surface of the photosensitive resin layer or the cured photosensitive resin layer. The concentration of the remaining solvent varies greatly depending on the drying conditions such as the drying temperature and the amount of warm air, the speed at which the liquid photosensitive resin composition is applied onto the cylindrical support, and the application method.

  The solvent component contained in the photosensitive resin composition layer or the cured photosensitive resin layer of the present invention is preferably 5 ppm to 1000 ppm. If the residual solvent is within this range, a fine pattern can be formed without any problem. The quantification of the solvent residual amount of the present invention is carried out by the following method. In the cross section of the photosensitive resin layer or the cured photosensitive resin layer formed on the cylindrical support, a small amount of resin in a portion within a thickness of 0.5 mm near the cylindrical support is collected, and this is used as an analysis sample. To do. This sample is analyzed using a pyrolysis GC / MS analyzer. The temperature of the pyrolysis furnace is set to 100 ° C. to 200 ° C., and the solvent component contained in the resin is evaporated. The generated gas was collected using a cryofocusing method in which liquid nitrogen was trapped with liquid nitrogen. The collected gas is analyzed using GC / MS. Since it is separated by gas chromatography and analyzed using a mass spectrometer, even if an organic compound having an unreacted polymerizable unsaturated group is generated as a gas component, it can be separated and the solvent component is identified. be able to. Furthermore, after the solvent component can be identified, the corresponding solvent having a known weight is analyzed by the same method, and it is confirmed how much strength can be detected by the detection unit of the analyzer, and compared with the analysis result of the resin component. Then, the weight of the solvent contained in the resin sample is obtained. Since the weight of the resin sample used for the analysis is initially weighed, the solvent content in the resin sample can be quantified from these values. It is desirable to change the temperature of the pyrolysis furnace depending on the sample. For example, it is desirable to grasp the decomposition characteristics of the resin in advance by thermogravimetric analysis. In the case of a resin that is easily decomposed, the temperature can be set lower. Components that interfere with the measurement are pyrolyzed components, but since this analysis method is equipped with a mass spectrometer, by changing the pyrolysis temperature and observing changes in the amounts of these components, It is also possible to separate a component that has been thermally decomposed or a component that has been present as a solvent.

  As a method of molding the resin composition of the present invention into a sheet or cylinder, an existing resin molding method can be used. For example, a casting method, a method of extruding a resin from a nozzle or a die with a machine such as a pump or an extruder, adjusting the thickness with a blade, and adjusting the thickness by calendering with a roll can be exemplified. In that case, it is also possible to perform the molding while heating within a range that does not deteriorate the performance of the resin. Moreover, you may perform a rolling process, a grinding process, etc. as needed. Usually, it is often formed on an underlay called a back film made of a material such as PET or nickel, but it may be formed directly on a cylinder of a printing machine. Further, a cylindrical support made of fiber reinforced plastic (FRP), plastic, or metal can also be used. The cylindrical support can be hollow with a constant thickness for weight reduction. The role of the back film or the cylindrical support is to ensure the dimensional stability of the printing original plate. Therefore, it is necessary to select one having high dimensional stability. When evaluated using the linear thermal expansion coefficient, the upper limit value of a preferable material is 100 ppm / ° C. or less, more preferably 70 ppm / ° C. or less. Specific examples of materials include polyester resin, polyimide resin, polyamide resin, polyamideimide resin, polyetherimide resin, polybismaleimide resin, polysulfone resin, polycarbonate resin, polyphenylene ether resin, polyphenylene thioether resin, polyethersulfone resin, all Examples thereof include liquid crystal resins composed of aromatic polyester resins, wholly aromatic polyamide resins, and epoxy resins. Further, these resins can be laminated and used. For example, a sheet or the like in which layers of polyethylene terephthalate having a thickness of 50 μm are laminated on both surfaces of a 4.5 μm thick wholly aromatic polyamide film may be used. In addition, a porous sheet, for example, a cloth formed by knitting fibers, a nonwoven fabric, a film in which pores are formed, or the like can be used as a back film. When a porous sheet is used as the back film, the photosensitive resin cured product layer is integrated with the back film by photocuring after impregnating the photosensitive resin composition into the pores, so that high adhesion is obtained. be able to. The fibers forming the cloth or nonwoven fabric include glass fibers, alumina fibers, carbon fibers, alumina / silica fibers, boron fibers, high silicon fibers, potassium titanate fibers, inorganic fibers such as sapphire fibers, natural materials such as cotton and hemp Examples thereof include semi-synthetic fibers such as fibers, rayon and acetate, and synthetic fibers such as nylon, polyester, acrylic, vinylon, polyvinyl chloride, polyolefin, polyurethane, polyimide, and aramid. Further, cellulose produced by bacteria is a highly crystalline nanofiber, and is a material capable of producing a thin nonwoven fabric with high dimensional stability.

  Examples of a method for reducing the linear thermal expansion coefficient of the back film include a method of adding a filler, a method of impregnating or coating a resin on a mesh cloth such as wholly aromatic polyamide, or a glass cloth. As the filler, generally used organic fine particles, inorganic fine particles such as metal oxide or metal, organic / inorganic composite fine particles, and the like can be used. In addition, porous fine particles, fine particles having cavities inside, microcapsule particles, and layered compound particles in which a low molecular compound intercalates can be used. In particular, metal oxide fine particles such as alumina, silica, titanium oxide, and zeolite, latex fine particles made of polystyrene / polybutadiene copolymer, natural product-based organic fine particles such as highly crystalline cellulose, and the like are useful.

  By performing physical and chemical treatments on the surface of the back film or cylindrical support used in the present invention, the adhesion with the photosensitive resin composition layer or the adhesive layer can be improved. Examples of the physical treatment method include a sand blast method, a wet blast method for injecting a liquid containing fine particles, a corona discharge treatment method, a plasma treatment method, an ultraviolet ray or vacuum ultraviolet ray irradiation method, and the like. The chemical treatment method includes a strong acid / strong alkali treatment method, an oxidant treatment method, a coupling agent treatment method, and the like.

  The molded photosensitive resin composition layer is crosslinked by light irradiation to form a printing original plate. Further, it can be crosslinked by light irradiation while molding. Examples of the light source used for curing include a high pressure mercury lamp, an ultrahigh pressure mercury lamp, an ultraviolet fluorescent lamp, a germicidal lamp, a carbon arc lamp, a xenon lamp, and a metal halide lamp. The light applied to the photosensitive resin composition layer preferably has a wavelength of 200 nm to 300 nm. In particular, since many hydrogen abstraction type photopolymerization initiators have strong light absorption in this wavelength region, when having light with a wavelength of 200 nm to 300 nm, sufficient curability of the surface of the cured photosensitive resin layer is ensured. be able to. Although the light source used for curing may be one type, the curability of the resin may be improved by curing using two or more types of light sources having different wavelengths, so two or more types of light sources may be used. There is no problem.

  The thickness of the original plate used for laser engraving may be arbitrarily set according to the purpose of use, but when used as a printing plate, it is preferably in the range of 0.1 to 7 mm. In some cases, a plurality of materials having different compositions may be stacked. For example, a layer that can be engraved using a laser having an oscillation wavelength in the near infrared region such as a YAG laser, a fiber laser, or a semiconductor laser is formed on the outermost surface, and an infrared laser such as a carbon dioxide laser or the like is formed under the layer. It is also possible to form a layer capable of laser engraving using a visible / ultraviolet laser. By forming such a laminated structure, a relatively high-power carbon dioxide laser is used to deeply engrave a relatively rough pattern, and a very fine pattern near the surface is used using a near-infrared laser such as a YAG laser or fiber laser. Can be engraved. Since an extremely fine pattern may be engraved relatively shallowly, the thickness of the layer sensitive to the near infrared laser is preferably in the range of 0.01 mm to 0.5 mm. Thus, by laminating a layer sensitive to the near infrared laser and a layer sensitive to the infrared laser, the depth of the pattern engraved using the near infrared laser can be accurately controlled. This is because a layer that is sensitive to an infrared laser utilizes a phenomenon that is difficult to engrave with a near infrared laser. The difference in the fineness of the engraving pattern is caused by the difference in oscillation wavelength inherent in the laser apparatus, that is, the difference in the diameter of the laser beam that can be narrowed. When laser engraving is performed in this way, engraving can be performed using separate laser engraving equipment equipped with infrared laser and near infrared laser, and laser engraving equipment equipped with both infrared laser and near infrared laser can be used. It is also possible to use.

  The wettability of the surface of the laser engraving printing original plate of the present invention is an extremely important factor in ink acceptance and transfer. In the surface wettability evaluation carried out at a temperature of 25 ° C., 20 μl of an indicator liquid having a surface energy of 30 mN / m was dropped on the surface of the laser engraving printing original plate, and after 30 seconds, the droplet spread. When the maximum diameter is measured, the diameter of the droplet is preferably 4 mm or more and 20 mm or less. A more preferable range is 5 mm or more and 15 mm or less. In many cases, the indicator liquid spreads concentrically, but depending on the state of the original surface, the concentric circle may not necessarily spread. In that case, the minimum value of the diameter of the circle in which the expanded portion completely enters is defined as the maximum diameter of the expanded portion of the indicator droplet. If the maximum diameter of the portion where the droplets are wide is in the range of 4 mm or more and 20 mm or less, the printed matter does not become non-uniform by repelling the ink, and the ink remaining on the plate surface is suppressed.

  In the present invention, a cushion layer made of an elastomer can be formed below the layer to be laser engraved. In general, since the thickness of the layer to be laser engraved is 0.1 to several mm, the other lower layers may be made of materials having different compositions. The cushion layer is preferably an elastomer layer having a Shore A hardness of 20 to 70 degrees. When the Shore A hardness is 20 degrees or more, the printing quality can be ensured because the film is appropriately deformed. Moreover, if it is 70 degrees or less, it can play the role as a cushion layer. A more preferable range of Shore A hardness is 30 to 60 degrees.

  The cushion layer is not particularly limited, and any cushion layer may be used as long as it has rubber elasticity, such as a thermoplastic elastomer, a photocurable elastomer, and a thermosetting elastomer. It may be a porous elastomer layer having nanometer-level micropores. In particular, from the viewpoint of processability to a sheet-like or cylindrical printing plate, it is convenient and preferable to use a liquid photosensitive resin composition that is cured by light and to use a material that becomes elastomer after curing.

  Specific examples of the thermoplastic elastomer used for the cushion layer include SBS (polystyrene-polybutadiene-polystyrene), SIS (polystyrene-polyisoprene-polystyrene), SEBS (polystyrene-polyethylene / polybutylene-polystyrene), which are styrenic thermoplastic elastomers, and the like. Olefin-based thermoplastic elastomer, urethane-based thermoplastic elastomer, ester-based thermoplastic elastomer, amide-based thermoplastic elastomer, silicon-based thermoplastic elastomer, fluorine-based thermoplastic elastomer, and the like.

Examples of the photocurable elastomer include those obtained by mixing a photopolymerizable monomer, a plasticizer, a photopolymerization initiator, and the like with the thermoplastic elastomer, and a liquid composition obtained by mixing a photopolymerizable monomer, a photopolymerization initiator, etc. with a plastomer resin. Can be mentioned. In the present invention, unlike the design concept of the photosensitive resin composition, in which the function of forming a fine pattern is an important element, it is not necessary to form a fine pattern using light, and by curing by overall exposure, Since it is sufficient to ensure a certain level of mechanical strength, the degree of freedom in selecting a material is extremely high.
Moreover, non-sulfur cross-linked rubbers such as sulfur cross-linked rubber, organic peroxide, phenol resin initial condensate, quinone dioxime, metal oxide, and thiourea can also be used.
Furthermore, it is also possible to use a three-dimensionally crosslinked elastomer obtained by using a curing agent that reacts with a telechelic liquid rubber.

In the case of multilayering in the present invention, the position of the back film is below the cushion layer, that is, at the bottom of the printing original plate, or between the photosensitive resin layer capable of laser engraving and the cushion layer, that is, on the printing original plate. It does not matter at any position in the center.
Further, by forming a modified layer on the surface of the laser engraving printing plate of the present invention, the tack of the printing plate surface can be reduced and the ink wettability can be improved. Examples of the modified layer include a film treated with a compound that reacts with a surface hydroxyl group such as a silane coupling agent or a titanium coupling agent, or a polymer film containing porous inorganic particles.

  A widely used silane coupling agent is a compound having in its molecule a functional group highly reactive with the surface hydroxyl group of the substrate. Examples of such a functional group include a trimethoxysilyl group and a triethoxysilyl group. Group, trichlorosilyl group, diethoxysilyl group, dimethoxysilyl group, dimonochlorosilyl group, monoethoxysilyl group, monomethoxysilyl group, monochlorosilyl group. Further, at least one of these functional groups exists in the molecule, and is immobilized on the surface of the base material by reacting with the surface hydroxyl group of the base material. Further, the compound constituting the silane coupling agent of the present invention is selected from acryloyl group, methacryloyl group, active hydrogen-containing amino group, epoxy group, vinyl group, perfluoroalkyl group, and mercapto group as reactive functional groups in the molecule. Those having at least one functional group or those having a long-chain alkyl group can be used.

  Examples of titanium coupling agents include isopropyl triisostearoyl titanate, isopropyl tris (dioctyl pyrophosphate) titanate, isopropyl tri (N-aminoethyl-aminoethyl) titanate, tetraoctyl bis (di-tridecyl phosphite) titanate, Tetra (2,2-diallyloxymethyl-1-butyl) bis (di-tridecyl) phosphite titanate, bis (octylpyrophosphate) oxyacetate titanate, bis (dioctylpyrophosphate) ethylene titanate, isopropyltrioctanoyl titanate, isopropyl Dimethacrylisostearoyl titanate, isopropyltridodecylbenzenesulfonyl titanate, isopropylisostearoyl diacryl titanate Over DOO, isopropyl tri (dioctyl sulfate) titanate, isopropyl tricumylphenyl titanate, tetraisopropyl bis (dioctyl phosphite) may include compounds such as titanates.

When the coupling agent molecule immobilized on the surface has a polymerizable reactive group in particular, it is possible to obtain a stronger coating by irradiating light, heat, or an electron beam and crosslinking after immobilization on the surface. .
In the present invention, the above-described coupling agent is diluted with water-alcohol or acetic acid water-alcohol mixed solution as necessary. The concentration of the coupling agent in the treatment liquid is preferably 0.05 to 10.0% by weight.
The coupling agent treatment method in the present invention will be described. The treatment liquid containing the coupling agent is applied to the printing original plate or the surface of the printing plate after laser engraving. The method for applying the coupling agent treatment liquid is not particularly limited, and for example, an immersion method, a spray method, a roll coating method, or a brush coating method can be applied. Further, the coating treatment temperature and the coating treatment time are not particularly limited, but are preferably 5 to 60 ° C., and the treatment time is preferably 0.1 to 60 seconds. Furthermore, it is preferable to dry the treatment liquid layer on the surface of the resin plate under heating, and the heating temperature is preferably 50 to 150 ° C.

Before treating the printing plate surface with a coupling agent, a method of irradiating light in a vacuum ultraviolet region with a wavelength of 200 nm or less such as a xenon excimer lamp, or by exposing it to a high energy atmosphere such as plasma, a hydroxyl group on the printing plate surface. And the coupling agent can be immobilized at a high density.
In addition, when the layer containing inorganic porous particles is exposed on the printing plate surface, it is treated in a high-energy atmosphere such as plasma, and the organic layer on the surface is slightly etched away to remove minute particles on the printing plate surface. Unevenness can be formed. By this treatment, the effect of improving the ink wettability can be expected by reducing the tack of the printing plate surface and making the inorganic porous particles exposed on the surface easy to absorb the ink.

  In laser engraving, a relief image is created on an original by operating a laser device using a computer as an image to be formed as digital data. Any laser may be used for the laser engraving as long as the original plate includes a wavelength having absorption, but in order to perform engraving at a high speed, a laser with a high output is desirable. Infrared or infrared emitting solid lasers such as YAG lasers and semiconductor lasers are preferred. In addition, the second harmonic of a YAG laser having an oscillation wavelength in the visible light region, a copper vapor laser, an ultraviolet laser having an oscillation wavelength in the ultraviolet region, such as an excimer laser, and a YAG laser wavelength-converted to the third or fourth harmonic are It can be ablated by cutting the bonds of organic molecules and is suitable for fine processing. The laser may be continuous irradiation or pulse irradiation. In general, resin has absorption in the vicinity of 10 μm of carbon dioxide laser, so it is not essential to add a component that helps the absorption of laser light, but YAG laser has a wavelength in the vicinity of 1.06 μm. There is not much that has. In that case, it is necessary to add dyes and pigments, which are components that assist in the absorption of these. Examples of such dyes include poly (substituted) phthalocyanine compounds and metal-containing phthalocyanine compounds; cyanine compounds; squarylium dyes; chalcogenopyrylarylidene dyes; chloronium dyes; Indolizine dyes; bis (aminoaryl) polymethine dyes; merocyanine dyes; and quinoid dyes. Examples of pigments include carbon black, graphite, copper chromite, chromium oxide, cobalt chrome aluminate, dark inorganic pigments such as copper oxide and iron oxide, and metal powders such as iron, aluminum, copper and zinc, and these metals And those doped with Si, Mg, P, Co, Ni, Y or the like. These dyes and pigments may be used alone, in combination of a plurality, or in any form such as a multilayer structure. However, in the case of a system in which the photosensitive resin composition is cured using light, the amount of the organic / inorganic compound that absorbs a large amount of light at the wavelength of light used for curing should be within a range that does not hinder the photocurability. The addition ratio with respect to the total amount of the photosensitive resin composition is preferably 5 wt% or less, more preferably 2 wt% or less.

  Laser engraving is carried out in an oxygen-containing gas, generally in the presence of air or an air stream, but can also be carried out in the presence of carbon dioxide or nitrogen gas. After engraving is finished, the powdery or liquid substance slightly generated on the relief printing plate surface is washed with an appropriate method such as water containing a solvent or a surfactant, or a water-based cleaning agent is irradiated by a high-pressure spray or the like. Alternatively, it may be removed using a method of irradiating high-pressure steam.

  In the present invention, when the laser engraving printing original plate is irradiated with laser light to form a concave pattern, the laser engraving printing original plate surface can be heated to assist laser engraving. Examples of the heating method of the laser engraving printing original plate include a method of heating a sheet or cylindrical surface plate of a laser engraving machine using a heater, and a method of directly heating the surface of the laser engraving printing original plate using an infrared heater. Can do. The laser engraving property can be improved by this heating step. The degree of heating is preferably in the range of 50 ° C to 200 ° C, more preferably in the range of 80 ° C to 200 ° C, and still more preferably in the range of 100 ° C to 200 ° C.

  In the present invention, after engraving to form a concave pattern by irradiating a laser beam, following the step of removing powdery or viscous liquid residue remaining on the plate surface, the surface of the printing plate on which the pattern is formed has a wavelength of 200 nm to 450 nm. Post-exposure can be performed by irradiating light. This method is effective in removing tack on the surface. The post-exposure may be performed in any environment such as air, inert gas atmosphere, and water. This is particularly effective when the photosensitive resin composition used contains a hydrogen abstraction type photopolymerization initiator. Furthermore, before the post-exposure step, the printing plate surface may be exposed to a treatment liquid containing a hydrogen abstraction type photopolymerization initiator. Moreover, you may expose in the state which immersed the printing plate in the process liquid containing a hydrogen abstraction type photoinitiator.

  The printing original plate of the present invention is a relief image for a printing plate, a stamp / stamp, a design roll for embossing, a relief image for patterning an insulator, a resistor, and a conductor paste used for creating an electronic component, and a reflection of an optical component. Pattern formation of functional materials such as prevention films, color filters, (near) infrared absorption filters, alignment films, underlayers, light-emitting layers, electron transport layers, sealing in the manufacture of display elements such as liquid crystal displays or organic electroluminescence displays It can be applied and used for various applications such as coating film / pattern formation of agent layers, relief images for mold materials of ceramic products, relief images for displays such as advertisements and display boards, and prototypes / mother molds of various molded products.

EXAMPLES Hereinafter, although this invention is demonstrated based on an Example, this invention is not restrict | limited by these.
(1) Laser engraving Laser engraving was performed using a carbon dioxide laser engraving machine (trademark: ZED-mini-1000, UK, manufactured by ZED, USA, coherent, equipped with an output 250 W carbon dioxide laser). Engraving was performed by creating a pattern including halftone dots (80 lines per inch, area ratio 10%), line drawing with a 500 μm wide convex line, and 500 μm wide white line. If the engraving depth is set large, the area of the top portion of the fine halftone dot pattern cannot be secured, and the shape is broken and unclear, so the engraving depth is set to 0.55 mm.

(2) Number of residue wiping and residue remaining rate The residue on the relief printing plate after laser engraving uses a nonwoven fabric impregnated with ethanol or acetone (trademark: BEMCOT M-3, manufactured by Asahi Kasei Corporation, Japan). The residue on the relief printing plate was wiped off. The number of wiping processes necessary to remove the viscous liquid residue generated after engraving was defined as the number of residue wiping operations. A large number of times means a large amount of liquid residue. The number of wiping off of the excellent printing plate is 5 times or less, preferably 3 times or less.
Furthermore, the weights of the printing original plate before laser engraving, the printing plate immediately after laser engraving, and the relief printing plate after wiping were measured, and the residue rate at the time of engraving was determined by the following formula.
(Weight of plate immediately after engraving-Weight of plate after wiping) ÷ (Weight of original plate before engraving-Weight of plate after wiping) x 100
The residue rate of the excellent printing plate is 15 wt% or less, preferably 10 wt% or less.
After removing the residue remaining on the relief, post-exposure was performed by irradiating the printing plate surface with ultraviolet rays. The light used for post-exposure was ultraviolet fluorescent lamp (chemical lamp, center wavelength: 370 nm) and germicidal lamp (germisidal lamp, center wavelength: 253 nm).

(3) Shape of halftone dot portion The shape of the halftone dot portion having an area ratio of about 10% at 80 lpi (Lines per inch) was observed with an electron microscope at a magnification of 200 to 500 times. In the case where the halftone dot is conical or pseudo-conical (a divergent shape obtained by cutting the vicinity of the apex of the cone with a plane parallel to the bottom of the cone), the printing plate is good.

(4) Pore volume, average pore diameter, and specific surface area of porous body and nonporous body 2 g of porous body or nonporous body was taken in a sample tube, and conditions of 150 ° C. and 1.3 Pa or less in a pretreatment device And dried under reduced pressure for 12 hours. The pore volume, average pore diameter, and specific surface area of the dried porous body or non-porous body were measured by adsorbing nitrogen gas in a liquid nitrogen temperature atmosphere using Autosoap 3MP (trademark) manufactured by Cantachrome, USA. Measured. Specifically, the specific surface area was calculated based on the BET formula. The pore volume and average pore diameter were calculated based on a pore distribution analysis method called BJH (Brrett-Joyner-Halenda) method, assuming a cylindrical model from the adsorption isotherm at the time of nitrogen desorption.

(5) Loss on ignition of porous body and nonporous body Record the weight of the porous body or nonporous body for measurement. Next, the measurement sample was placed in a high-temperature electric furnace (FG31 type; manufactured by Yamato Kagaku Co., Ltd., Japan) and treated for 2 hours in an air atmosphere at 950 ° C. The change in weight after treatment was defined as loss on ignition.

(6) Standard deviation in particle size distribution of porous body and nonporous body The particle size distribution of the porous body and nonporous body was measured by a laser diffraction type particle size distribution analyzer (SALD-2000J type; Japan, (Manufactured by Shimadzu Corporation). According to the specification of the apparatus, it is described in the catalog that a particle size range from 0.03 μm to 500 μm can be measured. Methyl alcohol was used as a dispersion medium, and ultrasonic waves were applied for about 2 minutes to disperse the particles to prepare a measurement solution.

(7) Viscosity The viscosity of the photosensitive resin composition was measured at 20 ° C. using a B-type viscometer (B8H type; manufactured by Tokyo Keiki Co., Ltd., Japan).

(8) Measurement of number average molecular weight The number average molecular weight of resin (a ) was calculated | required by converting into polystyrene with known molecular weight using the gel permeation chromatography method (GPC method). Using a high-speed GPC device (HLC-8020 manufactured by Tosoh Corporation, Japan) and a polystyrene-filled column (trademark: TSKgel GMHXL; manufactured by Tosoh Corporation, Japan), the measurement was performed with tetrahydrofuran (THF). The column temperature was set to 40 ° C. As a sample to be injected into the GPC apparatus, a THF solution having a resin concentration of 1 wt% was prepared, and the injection amount was 10 μl. As the detector, for the resin (a), an ultraviolet absorption detector was used, and 254 nm light was used as monitor light . The resin (a ) used in the examples or comparative examples of the present invention had a polydispersity (Mw / Mn) obtained by using the GPC method greater than 1.1, and thus the number obtained by the GPC method. Average molecular weight Mn was adopted.

(9) Measurement of the number of polymerizable unsaturated groups The average number of polymerizable unsaturated groups present in the molecule of the synthesized resin (a) was obtained by removing unreacted low molecular components using liquid chromatography. Thereafter, molecular structure analysis was performed using a nuclear magnetic resonance spectrum method (NMR method).

(10) Measurement of softening temperature The softening temperature was measured using a viscoelasticity measuring device and a rotational rheometer manufactured by Rheometric Scientific F.E. The measurement frequency is 10 rad / sec, the heating rate is 10 ° C./min, and heating starts from room temperature. First, extrapolate the viscosity curve in the temperature range where the viscosity decreases greatly, and the temperature at the point where the baseline intersects Was determined as the softening point.

(Examples 1-7 , Reference Example 8 )
As solid resin (a) at 20 ° C., a styrene - butadiene - styrene (SBS, manufactured by Asahi Kasei Chemicals Corporation, trade "Tufprene A", the number-average molecular weight: 73,000) have use a, as shown in Table 1 An organic compound (b) , an inorganic porous material (f), a photopolymerization initiator, and other additives were added and kneaded using a kneader to prepare a resin composition. To 10 parts by weight of the obtained resin composition, 20 parts by weight of toluene was added to prepare a liquid photosensitive resin composition.

In addition, as the inorganic porous body (f), a trademark “Pyrospher C-1504” (hereinafter abbreviated as C-1504, number average particle diameter: 4.5 μm), which is a porous fine powder silica manufactured by Fuji Silysia Chemical Ltd. , Specific surface area 520 m ² / g, average pore diameter 12 nm, pore volume 1.5 ml / g, loss on ignition 2.5 wt%, oil absorption 290 ml / 100 g), trademark “Silicia 450” (hereinafter abbreviated as CH-450, number) Average particle diameter 8.0 μm, specific surface area 300 m ² / g, average pore diameter 17 nm, pore volume 1.25 ml / g, loss on ignition 5.0 wt%, oil absorption 200 ml / 100 g), trademark “Silicia 470” (hereinafter abbreviated) C-470, number average particle size 14.1 μm, specific surface area 300 m ² / g, average pore size 17 nm, pore volume 1.25 ml / g, ignition loss 5.0 wt%, oil absorption 180 ml / 100 g) was used. The porosity of the porous fine powder silica used was calculated with a density of 2 g / cm ³ and was 780 for Pyrosphere C-1504 and 800 for Cylicia 450. When the sphericity of Pyrospher C-1504, which was added porous spherical silica, was observed using a scanning electron microscope, almost all of the particles were 0.9 or more. Silicia 450 and Silicia 470 were porous silica but not spherical silica.

  Cushion tape with an adhesive layer on both sides was affixed on a glass fiber reinforced plastic cylindrical support having a thickness of 2 mm and an inner diameter of 213.384 mm to produce a cylindrical support with a cushion layer. While rotating the cylindrical support, the liquid photosensitive resin composition is applied onto the cylindrical support using a doctor blade, and then the solvent is used while blowing hot air while rotating the cylindrical support. Toluene was removed by drying. The resulting photosensitive resin composition layer was shaped using a grinder so that the thickness was 1.7 mm.

For Examples 1 to 7, a metal halide lamp (trade name “M056-L21” manufactured by Eye Graphics, Inc.) comes out from the opening (opening size: 40 mm × 310 mm) while rotating the cylindrical support. The photosensitive resin composition layer was irradiated with light in the atmosphere to form a cured photosensitive resin layer capable of laser engraving. The amount of energy irradiated was 4000 mJ / cm ² (a value obtained by integrating the illuminance measured with the UV-35-APR filter over time). The lamp illuminance on the irradiated surface was measured using a UV meter (trade name “UV-M02” manufactured by Oak Manufacturing Co., Ltd.). The lamp illuminance measured using a UV-35-APR filter was 100 mW / cm ² , and the lamp illuminance measured using a UV-25 filter was 14 mW / cm ² .

Thereafter, a pattern was formed on the surface using a carbon dioxide laser engraving machine. The shape of the obtained fine halftone dot portion was almost conical and good.
In Reference Example 8, a photosensitive resin composition layer was formed in the same manner as in Example 1 on a cylindrical support with a cushion. A negative film with a release agent having a pattern formed is attached to the surface of the obtained photosensitive resin composition layer from the side of the release agent layer, and then light from a chemical lamp (center wavelength: 370 nm) is passed through the negative film. Irradiation formed a latent image in the photosensitive resin composition layer. Further, the negative film was removed, and the uncured portion was developed and removed with a hydrocarbon solvent. The shape of the obtained fine halftone dot portion was almost conical and good.

The sample containing 0.25 mg of the solvent content contained in the cured photosensitive resin layer of the example was analyzed and determined. Using a pyrolysis GC / MS apparatus, the temperature of the pyrolysis furnace was set to 120 ° C., and the generated gas was collected using a cryofocusing method in which liquid nitrogen was trapped. Results collected gas was analyzed using GC / MS, the amount of Ah Ru toluene solvent remaining had entered from 50ppm in the range of 300 ppm. The pyrolysis GC / MS apparatus used for the analysis is a pyrolysis apparatus (trade name “Py-2010D” manufactured by Frontier Laboratories), a capillary gas chromatograph apparatus (abbreviated as GC), and a mass spectrometer (abbreviated as MS, JEOL Ltd.) Made by the trademark "Automass Sun").

In the photopolymerization initiator used in the examples, benzophenone (BP) is a hydrogen abstraction photopolymerization initiator (d), and 2,2-dimethoxy-2-phenylacetophenone (DMMAP) is a decay photopolymerization initiator. there were. Among the double bond-containing organic compounds used in the examples of the present invention, the alicyclic and aromatic derivatives are BZMA, CHMA and PEMA.
The photosensitive resin compositions of Examples 1 to 7 were all liquid at 20 ° C. The viscosity measured using a B-type viscometer was 50 Pa · s or more and 5 kPa · s or less in any system at 20 ° C.
The softening temperature of SBS used in the present invention was 130 ° C.

  The present invention relates to the creation of relief images for flexographic printing plates by laser engraving, the formation of patterns for surface processing such as embossing, the formation of relief images for printing such as tiles, the conductors of electronic components, semiconductors, insulators, pattern formation, optical components Pattern formation of functional materials such as antireflection films, color filters, (near) infrared cut filters, and alignment films, base layers, light emitting layers, electron transport layers in the production of display elements such as liquid crystal displays or organic electroluminescence displays It is most suitable for forming a coating film / pattern of a sealing material layer.

Claims (10)

Solid resin (a) at 20 ° C. having a polymerizable unsaturated group having a number average molecular weight of 1000 or more and 300,000 or less, an organic compound (b) having a polymerizable unsaturated group having a number average molecular weight of less than 1000, and volatility solvents, hydrogen abstraction type photopolymerization initiator (d), a liquid photosensitive resin composition containing a disintegrating photopolymerization initiator (e), the viscosity of the liquid photosensitive resin composition is 20 ° C. A photosensitive resin composition of 10 Pa · s or more and 50 kPa · s or less is placed on a cylindrical support to form a photosensitive resin layer, and then the photosensitive resin layer formed in a cylindrical shape is irradiated with light in the air to crosslink. A method for producing a laser-engravable cylindrical flexographic printing plate that is cured to form a cured photosensitive resin layer . The method for producing a laser-engravable cylindrical flexographic printing original plate according to claim 1, wherein the temperature at which the resin (a) softens is 350 ° C or lower. The method for producing a laser-engravable cylindrical flexographic printing original plate according to claim 1, wherein the resin (a) is a thermoplastic elastomer. The hydrogen abstraction type photopolymerization initiator (d) comprises at least one compound selected from benzophenones, xanthenes and anthraquinones, and the decay type photopolymerization initiator (e) comprises benzoin alkyl ethers, 2, 4. It consists of at least one compound selected from 2-dialkoxy-2-phenylacetophenones, acyloxime esters, azo compounds, organic sulfur compounds, and diketones . A method for producing a cylindrical flexographic printing original plate capable of laser engraving according to one item . The photosensitive resin composition further contains an inorganic porous body (f), the specific surface area of the inorganic porous body (f) is 10 m ² / g or more and 1500 m ² / g or less, and the average pore diameter is 1 nm or more and 1000 nm or less. and a pore volume 0.1 ml / g or more 10 ml / g or less, and the oil absorption may possible laser engraving according to any one of claims 1 to 4, characterized in that not more than 10 ml / 100 g or more 2000 ml / 100 g A method for producing a cylindrical flexographic printing original plate . The inorganic porous body (f) has a number average particle size of 0.1 μm or more and 100 μm or less, and at least 70% of the particles are spherical particles having a sphericity of 0.5 to 1. The method for producing a laser-engravable cylindrical flexographic printing original plate according to claim 5 . Between the step of placing the photosensitive resin composition on a cylindrical support and providing a photosensitive resin layer, and the step of irradiating the photosensitive resin composition formed in a cylindrical shape with light in the air to cure by crosslinking. The method for producing a laser-engravable cylindrical flexographic printing original plate according to any one of claims 1 to 6, further comprising a step of drying and removing the volatile solvent. It includes 450nm or less light than the wavelength 200nm to light irradiated to the photosensitive resin layer formed into a cylindrical shape, and the illuminance on the plate surface of the light used for photo-crosslinking curing of the photosensitive resin composition, ORC Manufacturing If company made of UV Gauge "UV-M02" and (R) was measured using a UV-35-APR filter, it is 20 mW / cm ² or more and measured using the UV meter and UV-25 filter The method for producing a laser-engravable cylindrical flexographic printing original plate according to any one of claims 1 to 7 , wherein the method is 5 mW / cm ² or more. A laser beam is irradiated to the printing original plate obtained by the method for producing a cylindrical flexographic printing original plate capable of laser engraving according to any one of claims 1 to 8 , and the concave pattern is formed by removing the laser irradiation portion. circular cylindrical flexographic printing plate manufacturing method of you and a step of forming. After the step of forming a concave pattern by engraving the printing plate irradiated with Les Za light, washing removal of debris generated during engraving, Thereafter, the following light 450nm or more wavelength 200 nm, printing plate to form a pattern The method for producing a cylindrical flexographic printing plate according to claim 8 , comprising a step of irradiating the surface.