JP2010115792A - Method for manufacturing original cylindrical printing plate for laser engraving - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a manufacturing method which is suited for manufacturing a large number of original cylindrical printing plates designed for forming an uneven pattern on the surface by means of laser engraving. <P>SOLUTION: This method of manufacturing the original cylindrical printing plate for laser engraving comprises (1) the process to form a surface regulating layer by applying a curable resin composition to the surface of a hollow cylindrical support (a) with an uneven part, (2) the process to bring the a sheet-like resin into contact with the surface regulating layer by winding the sheet-like resin around the surface of the surface regulating layer, and (3) the process to cure the surface regulating layer. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a method for producing a cylindrical printing original plate for laser engraving.

In recent years, when producing resin relief printing such as flexographic printing, dry offset printing, and letterpress printing, or when performing surface processing such as embossing, the resin in the irradiated part is removed by laser irradiation. Thus, a laser engraving method for forming a concavo-convex pattern on the surface has come to be used.
Materials applied to the laser engraving method include vulcanized rubber, a cured photosensitive resin obtained by photocuring a photosensitive resin composition, and a thermosetting obtained by thermosetting a thermosetting resin composition. A cured resin is used. In particular, in recent years, a technique for laser engraving a cured photosensitive resin has been increasing from the viewpoint of shortening the processing time.

  Patent Document 1 describes a laser engraving printing original plate obtained by photocuring a photosensitive resin composition containing a thermoplastic elastomer as a main raw material, and winding a sheet-like photosensitive resin on a cylindrical support, A method for producing a cylindrical printing original plate by welding the parts is described.

Japanese Patent No. 2846954

However, in patent document 1, there is no description regarding the surface state of the cylindrical support body to be used.
In addition, the hollow cylindrical support made of fiber-reinforced plastic used in the printing field is usually manufactured on the premise that a sheet-like printing plate is attached to the surface, so that a ribbon-like glass cloth or the like is spirally wound. It is manufactured by impregnating the fiber with a liquid epoxy resin or the like, and then undergoes thermosetting, surface grinding, and polishing processes.
Therefore, the surface of the cylindrical support has few irregularities, but the cylindrical support with few irregularities becomes very expensive due to long manufacturing time and complicated process. Therefore, there is a need for a manufacturing method that simplifies the manufacturing process of the cylindrical printing original plate including the manufacturing of the cylindrical support and can be produced in large quantities.

  The problem to be solved by the present invention is to provide a production method suitable for producing a large amount of a cylindrical printing original plate for forming an uneven pattern on the surface by laser engraving.

  In view of the above circumstances, the present inventors have intensively studied to solve the above-mentioned problems. As a result, (1) a curable resin composition is applied to the surface of the hollow cylindrical support (a) where the uneven portion exists. A step of forming a surface adjustment layer, (2) a step of winding a sheet-like resin on the surface adjustment layer and bringing it into contact with the surface adjustment layer, and (3) a step of curing the surface adjustment layer It has been found that the above-mentioned problems can be solved by the method for producing a cylindrical printing original plate for engraving, and the present invention has been completed.

The present invention is as follows.
1. A method for producing a cylindrical printing original for laser engraving,
(1) The process of apply | coating a curable resin composition to the surface of a hollow cylindrical support body (a) in which an uneven | corrugated | grooved part exists, and forming a surface adjustment layer,
(2) A step of winding a sheet-like resin on the surface adjustment layer and bringing it into contact with the surface adjustment layer;
(3) A method for producing a cylindrical printing original plate for laser engraving, comprising a step of curing the surface adjustment layer.
2. In the step (3), the surface conditioning layer is cured by at least one curing method selected from the group consisting of thermosetting, photocuring, and moisture absorption curing. A method for producing a cylindrical printing original plate for laser engraving as described in 1.
3. The hollow cylindrical support (a) contains a fiber reinforced plastic; Or 2. A method for producing a cylindrical printing original plate for laser engraving as described in 1.
4). 2. The fiber reinforced plastic contains at least one resin selected from the group consisting of polyester, polyamide, epoxy, polyurethane, and polyimide; A method for producing a cylindrical printing original plate for laser engraving as described in 1.
5). The fiber reinforced plastic contains at least one fiber selected from the group consisting of polyester fiber, polyimide fiber, polyamide fiber, polyolefin fiber, cellulose fiber, glass fiber, carbon fiber, metal fiber, and ceramic fiber; . Or 4. A method for producing a cylindrical printing original plate for laser engraving as described in 1.
6). 4. The fiber is at least one type of fiber selected from the group consisting of woven fabric, non-woven fabric, and knitted fabric. A method for producing a cylindrical printing original plate for laser engraving as described in 1.
7). 4. The thickness of the fiber is 10 nm or more and 50 μm or less. Or 6. A method for producing a cylindrical printing original plate for laser engraving as described in 1.
8). 1. The thickness of the hollow cylindrical support (a) is 0.1 mm or more and 2 mm or less. To 7. The manufacturing method of the printing original plate for laser engraving of any one of these.
9. The ten-point average roughness Rz of the concavo-convex portion is 5 μm or more and 100 μm or less. To 8. The manufacturing method of the cylindrical printing original plate for laser engraving of any one of these.
10. 1. The thickness of the surface adjustment layer is 20 μm or more and 200 μm or less. To 9. The manufacturing method of the cylindrical printing original plate for laser engraving of any one of these.
11. 1. The surface of the surface adjustment layer has adhesiveness, and the surface tack of the surface adjustment layer is 300 gf / cm or more and 2 kgf / cm or less. To 10. The manufacturing method of the cylindrical printing original plate for laser engraving of any one of these.
12 The sheet-like resin is selected from the group consisting of polyamide, polyester, polyurethane, polycarbonate, polyether polyol, polyvinyl alcohol, vinyl alcohol-vinyl acetate copolymer, styrene-butadiene copolymer, and styrene-isoprene copolymer. At least one kind of resin. To 11. The manufacturing method of the cylindrical printing original plate for laser engraving of any one of these.
13. 1. The thickness of the sheet-like resin is 0.1 mm or more and 5 mm or less. To 12. The manufacturing method of the cylindrical printing original plate for laser engraving of any one of these.
14 1. To 13. A method for producing a laser engraving cylindrical printing plate, comprising a laser engraving step of forming a concave pattern by irradiating a laser beam onto a cylindrical printing original plate for laser engraving produced by the method according to any one of the above.
15. 13. the laser engraved cylindrical printing plate is used in an application selected from flexographic printing, dry offset printing, and gravure printing; The manufacturing method of the laser-engraving cylindrical printing plate of description.
16. 15. A dry offset printing method for printing on the surface of a cylindrical substrate using the laser engraved cylindrical printing plate described in 1.
17. 15. Use ink containing aliphatic hydrocarbon and / or aromatic hydrocarbon. The dry offset printing method described in 1.

  ADVANTAGE OF THE INVENTION According to this invention, the manufacturing method suitable for manufacturing the cylindrical printing original plate for forming an uneven | corrugated pattern on the surface by laser engraving with high productivity can be provided.

  Hereinafter, the best mode for carrying out the present invention (hereinafter referred to as “the present embodiment”) will be described in detail. In addition, this invention is not limited to the following embodiment, It can implement by changing variously within the range of the summary.

[Method for producing cylindrical printing original plate]
The method for producing a cylindrical printing original plate for laser engraving according to the present embodiment includes (1) applying a curable resin composition to the surface of a hollow cylindrical support (a) having a concavo-convex portion, and forming a surface adjustment layer. A cylindrical printing for laser engraving, comprising: (2) winding a sheet-like resin on the surface adjustment layer and bringing it into contact with the surface adjustment layer; and (3) curing the surface adjustment layer. This is a method for producing an original plate.
The manufacturing method of the cylindrical printing original plate for laser engraving according to the present embodiment uses the hollow cylindrical support (a) having a concavo-convex portion on the surface to form the cylindrical printing original plate by forming the surface adjustment layer. It can be manufactured with high productivity.

[Step (1)]
In the step (1), the surface adjustment layer is formed by applying the curable resin composition to the surface of the hollow cylindrical support (a) where the uneven portion is present.
By applying the curable resin composition on the hollow cylindrical support (a), a surface adjustment layer can be laminated on the surface of the hollow cylindrical support (a).

Examples of the curable resin composition include a photocurable adhesive, a thermosetting adhesive, and an anaerobic adhesive.
The photocurable adhesive may be liquid or solid at 20 ° C.
When it is liquid at 20 ° C., the viscosity is preferably 100 Pa · s or more and 10 kPa · s or less, more preferably 500 Pa · s or more and 5 kPa · s or less, and further preferably 1 kPa · s or more and 5 kPa · s or less. is there.
If the viscosity at 20 ° C. is within the above range, the shape can be maintained without causing dripping by resisting gravity when coated on the hollow cylindrical support (a).

  When it is solid at 20 ° C., it is preferably heated to a temperature at which the photocurable adhesive is softened when the sheet-like resin is wound around the hollow cylindrical support (a) in the step (2). The photocurable adhesive that is solid at 20 ° C. is preferably dissolved in a solvent and applied using a method such as spray coating, blade coating, or roll coating, and then the solvent is removed by drying. A solventless type hot-melt photocurable adhesive may be applied in a heated state.

  The thermosetting adhesive contains a radical polymerization type thermosetting adhesive containing a type of thermal polymerization initiator that generates radicals upon heating, and a microcapsule type thermal polymerization initiator that generates an acid or base upon heating. Examples thereof include a ring-opening polymerization type thermal polymerization adhesive. These heat-polymerizable adhesives may be liquid or solid at 20 ° C., but are preferably liquid from the viewpoint of ease of moldability. A solid method is preferably a method of laminating while heating on a cylindrical support, and a liquid material can be laminated by a method such as spray coating, blade coating or roll coating.

  The anaerobic adhesive is an adhesive that cures by absorbing moisture in the air, and preferably contains an isocyanate compound or the like from the viewpoint of high reactivity and ease of handling. The anaerobic adhesive may be liquid or solid at 20 ° C., but is preferably liquid from the viewpoint of ease of moldability. A solid method is preferably a method of laminating while heating on a cylindrical support, and a liquid material can be laminated by a method such as spray coating, blade coating or roll coating.

[Hollow cylindrical support (a)]
The hollow cylindrical support (a) has an uneven portion on the surface.
The ten-point average roughness Rz of the uneven portion on the surface of the hollow cylindrical support (a) is preferably 5 μm or more and 100 μm or less, more preferably 5 μm or more and 50 μm or less, and further preferably 10 μm or more and 30 μm or less. It is.
If the height difference is within the above range as the ten-point average roughness Rz, the ten-point average roughness Rz can be sufficiently covered with the surface adjustment layer and obtained by polishing the surface irregularities, and is 3 μm or less. It is not necessary to use an expensive hollow cylindrical support (a), and the manufacturing time of the hollow cylindrical support (a) can be shortened.
In the present embodiment, the ten-point average roughness Rz is a reference length extracted from the roughness curve in the direction of the average line, and measured from the average line of the extracted portion in the direction of the vertical magnification, from the highest peak. The sum of the average absolute value of the elevations up to the 5th summit and the average value of the absolute values of the elevations from the lowest valley bottom to the 5th, and expressed in micrometers (μm) It is.
The ten-point average roughness Rz can be measured by the method described in the following examples.

The hollow cylindrical support (a) is preferably a fiber reinforced plastic, and more preferably a fiber reinforced plastic sleeve.
The fiber reinforced plastic preferably contains at least one resin selected from the group consisting of polyester, polyamide, epoxy, polyurethane, and polyimide.
The fiber reinforced plastic preferably contains at least one fiber selected from the group consisting of polyester fiber, polyimide fiber, polyamide fiber, polyolefin fiber, cellulose fiber, glass fiber, carbon fiber, metal fiber, and ceramic fiber. . The fibers are preferably at least one type of fiber selected from the group consisting of woven fabrics, non-woven fabrics, and knitted fabrics, and the thickness of the fibers is preferably 10 nm to 50 μm. The thickness of the fiber is more preferably 100 nm or more and 25 μm or less, and still more preferably 100 nm or more and 10 μm or less.
If the thickness of the fiber is within the above range, the mechanical strength can be secured and the degree of surface irregularities can be reduced.

The thickness of the hollow cylindrical support (a) is preferably from 0.1 mm to 2 mm, more preferably from 0.3 mm to 1 mm, and further preferably from 0.4 mm to 0.8 mm. is there.
If the thickness of the hollow cylindrical support (a) is within the above range, sufficient mechanical strength can be ensured without breaking or cracking, and the weight can be reduced.

[Surface Treatment of Hollow Cylindrical Support (a)]
By performing a physical or chemical treatment on the surface of the hollow cylindrical support (a), the adhesion with the curable resin composition 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, and an ultraviolet ray or vacuum ultraviolet ray irradiation method.
Examples of the chemical treatment method include a strong acid / strong alkali treatment method, an oxidant treatment method, and a coupling agent treatment method.

[Surface adjustment layer]
By forming the surface adjustment layer, the irregularities on the surface of the hollow cylindrical support (a) can be sufficiently covered.
The thickness of the surface adjustment layer can be set appropriately according to the unevenness of the hollow cylindrical support (a) to cover the unevenness of the surface of the hollow cylindrical support (a). it can. The thickness of the surface adjustment layer is preferably 20 μm or more and 200 μm or less, more preferably 30 μm or more and 150 μm or less, and further preferably 50 μm or more and 100 μm or less.
In the present embodiment, by appropriately setting the thickness of the surface adjustment layer with respect to the ten-point average roughness Rz of the concavo-convex portion within the above range, the height difference of the concavo-convex on the surface of the hollow cylindrical support (a) can be reduced. It can be fully coated.
By providing the surface adjustment layer, it is possible to cover the irregularities on the surface of the hollow cylindrical support (a), and the 10-point average surface roughness Rz can be 3 μm or less. Is more preferably 2 μm or less, and further preferably 1 μm or less.

[Step (2)]
In the step (2), a sheet-like resin is wound on the surface adjustment layer and brought into contact with the surface adjustment layer.
Specifically, a sheet-like resin is wound on the surface adjustment layer laminated on the surface of the cylindrical support (a).
As a method of winding the sheet-shaped resin, it is preferable to wind the sheet-shaped resin in a cylindrical shape, and it may be wound around the entire circumference of the cylindrical support (a), or may be wound around a part of the circumferential direction. May be. Further, it may be wound manually or using a jig. After winding the sheet-like resin, it is preferable to temporarily fix the surface adjustment layer on the surface adjustment layer using a tape or the like and then cure the surface adjustment layer in the step (3).

[Sheet resin]
The sheet-like resin is preferably made of at least one material selected from the group consisting of a thermoplastic resin, a photosensitive resin composition, and a thermosetting resin composition.
As a sheet-like resin, a photosensitive resin cured product or a thermosetting resin cured product on a sheet-like support made of a thermoplastic resin from the viewpoint of ensuring laser engraving property, image forming property, flexibility, and mechanical strength. It is preferable that it is a sheet-like laminated body with which is laminated | stacked.

In the present embodiment, the cured photosensitive resin is a cured resin obtained by photocuring the photosensitive resin composition, and the cured thermosetting resin is obtained by thermosetting the thermosetting resin composition. (Hereinafter simply referred to as “photosensitive resin composition and thermosetting resin composition”, “resin composition”, “photosensitive resin cured product and thermosetting resin cured product”, “resin curing”) May be described as "thing").
The resin composition is selected from the group consisting of polyamide, polyimide, polyurethane, polyester, polycarbonate, polyether polyol, polyvinyl alcohol, vinyl alcohol-vinyl acetate copolymer, styrene-butadiene copolymer, and styrene-isoprene copolymer. It is preferable to contain at least one kind of resin.

When the cylindrical printing original plate is for flexographic printing, the resin composition may be a polyurethane having a relatively low hardness, such as polyurethane, polyester, polycarbonate, polyether polyol, styrene-butadiene copolymer, and styrene-isoprene copolymer. It is preferable to contain a material.
When the cylindrical printing original plate is for dry offset printing or gravure printing, the resin composition is made of a material such as polyamide, polyimide, polyvinyl alcohol, vinyl alcohol-vinyl acetate copolymer, and polycarbonate having a relatively high hardness. It is preferable to contain.

The sheet-like support preferably has a thickness of 10 μm or more and 500 μm or less from the viewpoint of dimensional stability, lightness, flexibility, and flatness. The thickness of the sheet-like support is more preferably 50 μm or more and 300 μm or less, and still more preferably 50 μm or more and 200 μm or less.
Examples of the material for the sheet-like support include metals such as nickel, aluminum, and iron, and a thermoplastic resin that is at least one selected from the group consisting of polyester, polyamide, and polyimide.

  The sheet-like resin is preferably a material that transmits the light to be used, and the light transmittance of the sheet-like resin at the wavelength of the light to be used is preferably 50% or more and 100% or less, more preferably 70% or more. 100% or less, more preferably 80% or more and 100% or less.

The thickness of the sheet-like resin is preferably from 0.1 mm to 5 mm.
If the thickness of the sheet-like resin is within this range, it can be used for printing applications such as flexographic printing, dry offset printing, and gravure printing.

[Step (3)]
In the step (3), the surface adjustment layer is cured. By curing the surface adjustment layer, the hollow cylindrical support (a) and the sheet-like resin can be fixed.

It is preferable that the curing method of the surface adjustment layer is at least one curing method selected from the group consisting of thermal curing, photocuring, and moisture absorption curing.
Hygroscopic curing is a method of curing with moisture in the air, and thermal curing and photocuring are curing methods described below.

It is preferable that the surface of the surface adjustment layer has adhesiveness. The surface tack is preferably 300 gf / cm or more and 2 kgf / cm or less, and more preferably 500 gf / cm or more and 2 kgf / cm or less.
If the surface tack of the surface of the surface adjustment layer is within the above range, it is effective for temporarily fixing the sheet-like resin.

In the present embodiment, a cylindrical printing original plate for laser engraving with high productivity and high accuracy can be manufactured by steps (1) to (3).
As the cylindrical printing original plate for laser engraving, the outer diameter accuracy is preferably ± 30 μm or less, more preferably ± 20 μm or less.

  In this Embodiment, it is preferable that the resin composition of a sheet-like resin contains resin (b) and the organic compound (c).

[Resin (b)]
The number average molecular weight of the resin (b) is preferably 1000 or more and 300,000 or less, more preferably 2000 or more and 200,000 or less, and further preferably 5000 or more and 150,000 or less.
If the number average molecular weight of the resin (b) is 1000 or more, the cured resin obtained by crosslinking later maintains strength, and can be used repeatedly when used as a printing substrate or the like.
If the number average molecular weight of the resin (b) is 300,000 or less, the melt viscosity of the resin composition does not rise excessively during extrusion molding, and a sheet-like resin cured product can be produced.

  In the present embodiment, the number average molecular weight means a value measured by gel permeation chromatography, calibrated with polystyrene having a known molecular weight, and converted.

The resin (b) may have a polymerizable unsaturated group in the molecule.
Preferred examples of the resin (b) include compounds having an average number of polymerizable unsaturated groups of 0.7 or more per molecule.
If the average number of polymerizable unsaturated groups is 0.7 or more per molecule, the cured resin has excellent mechanical strength and good durability, and can withstand repeated use, particularly as a printing substrate. It is preferable.
From the viewpoint of the mechanical strength of the cured resin, the number of polymerizable unsaturated groups in the resin (b) is preferably 0.7 or more per molecule, more preferably 1 or more, more preferably 1 or more. 10 or less, more preferably 1 or more and 5 or less.
The upper limit of the number of polymerizable unsaturated groups per molecule of the resin (b) is not particularly limited, but the number of polymerizable unsaturated groups per molecule is preferably 20 or less. If the number of polymerizable unsaturated groups per molecule of the resin (b) is 20 or less, shrinkage during curing can be suppressed to a low level, and occurrence of cracks in the vicinity of the surface can also be suppressed.

  In the present embodiment, having a polymerizable unsaturated group in the molecule means that the polymerizable unsaturated group is directly in the end of the polymer main chain, the end of the polymer side chain, in the polymer main chain, and in the polymer side chain. This includes cases where groups are attached.

Examples of the resin (b) include compounds having a polymerizable unsaturated group in the molecule with a polymer as shown below as a skeleton.
Examples of polymers include polyolefins such as polyethylene and polypropylene; polydienes such as polybutadiene and polyisoprene; polyhaloolefins such as polyvinyl chloride and polyvinylidene chloride; polystyrene, polyacrylonitrile, polyvinyl alcohol, polyvinyl acetate, polyvinyl acetal , Polymers having hetero atoms in the main chain such as polyacrylic acid, poly (meth) acrylic acid esters, poly (meth) acrylamide, polyester, polycarbonate, polyacetal, polyurethane, polyamide, polyurea, polyether polyol, and polyimide, One or two selected from the group consisting of vinyl alcohol-vinyl acetate copolymer, styrene-butadiene copolymer, styrene-isoprene copolymer and the like It may be used or more polymers. When using a plurality of polymers, either a copolymer or a blend may be used.

When a flexible relief image is required as in flexographic printing plate applications, as part of the resin (b), a liquid resin having a glass transition temperature of 20 ° C. or lower, preferably a liquid resin having a glass transition temperature of 0 ° C. or lower. Can also be added.
Liquid resins include, for example, hydrocarbons such as polyethylene, polybutadiene, hydrogenated polybutadiene, polyisoprene, and hydrogenated poisoprene; polyesters such as adipate and polycaprolactone; polyethylene such as polyethylene glycol, polypropylene glycol, and polytetramethylene glycol Examples include ethers; aliphatic polycarbonates; silicones such as polydimethylsiloxane; polymers of (meth) acrylic acid and / or derivatives thereof, and mixtures and copolymers thereof.
The content of the liquid resin is preferably 30% by mass to 100% by mass with respect to the entire resin (b).
As the liquid resin, unsaturated polyurethanes having a polycarbonate structure are preferable from the viewpoint of weather resistance. Examples of the unsaturated polyurethane include a resin having a polymerizable unsaturated group such as an acrylate group or a methacrylate group at the end of the polyurethane molecular chain, and a resin having a double bond in the polyurethane molecular chain.

As a method of introducing a polymerizable unsaturated group into the molecule of the resin (b), for example, a method of directly polymerizing using a monomer having a polymerizable unsaturated group introduced into the molecular end or molecular chain thereof. Can be mentioned.
As another method, a method in which a resin (polymer) and a compound having a polymerizable unsaturated group are reacted to introduce a polymerizable unsaturated group into the terminal of the resin can also be mentioned. Specifically, it has a plurality of reactive groups such as a hydroxyl group, amino group, epoxy group, carboxyl group, acid anhydride group, ketone group, hydrazine residue, isocyanate group, isothiocyanate group, cyclic carbonate group, and ester group. The compound is allowed to react with a binder having a plurality of functional groups capable of binding to a reactive group (for example, when the reactive group is a hydroxyl group or an amino group, examples of the binder include polyisocyanate), and the molecular weight. The resin obtained by the reaction is reacted with a compound having a functional group capable of reacting with the terminal binding group of the resin and a polymerizable unsaturated group. Then, a polymerizable unsaturated group is introduced into the terminal of the resin.

When the cured resin is used as a printing substrate for laser engraving, it is preferable to use a polymer having high thermal decomposability as the resin (b). For example, polymers having α-methylstyrene, methacrylic acid ester, and acrylic acid ester units, or a carbonate bond and a carbamate bond in the molecule are known as highly thermally decomposable compounds.
As an index of thermal decomposability, thermogravimetric data obtained by measuring weight loss when a sample is heated in an inert gas atmosphere can be used.
The temperature at which the weight of the resin (b) is halved is preferably in the range of 150 ° C. or higher and 450 ° C. or lower. The temperature at which the weight of the resin (b) is halved is more preferably in the range of 250 ° C. or higher and 400 ° C. or lower, and still more preferably in the range of 250 ° C. or higher and 380 ° C. or lower.

  As the resin (b), a compound in which thermal decomposition occurs in a narrow temperature range is preferable. As an indicator that thermal decomposition occurs in a narrow temperature range, in thermogravimetric analysis, the difference between the temperature at which the weight decreases to 80% of the initial weight and the temperature at which the weight decreases to 20% of the initial weight is 100 ° C. or less. It is preferable that The temperature difference is more preferably 80 ° C. or less, and further preferably 60 ° C. or less.

[Organic compound (c)]
The organic compound (c) is a compound having a polymerizable unsaturated group involved in radical polymerization reaction or ring-opening polymerization reaction, and the number average molecular weight is 1000 or less in consideration of easiness of dilution with the resin (b). It is preferable that
Examples of the organic compound (c) include olefins such as ethylene, propylene, styrene and divinylbenzene; acetylenes; (meth) acrylic acid and derivatives thereof; haloolefins; unsaturated nitriles such as acrylonitrile; (meth) acrylamide Allyl compounds such as allyl alcohol and allyl isocyanate; unsaturated dicarboxylic acids such as maleic anhydride, maleic acid, fumaric acid, and itaconic acid and their derivatives; vinyl acetates; N-vinylpyrrolidone; Carbazole; cyanate esters and the like.
As the organic compound (c), derivatives such as (meth) acrylic acid and (meth) acrylic acid ester are preferable from the viewpoint of variety and price.

  As the derivative, an alicyclic compound having a functional group such as a cycloalkyl group, a bicycloalkyl group, a cycloalkene group, and a bicycloalkene group; a functional group such as a benzyl group, a phenyl group, a phenoxy group, a methylstyryl group, and a styryl group An aromatic compound having a group; an ester compound or an amide compound such as a compound having a functional group such as an alkyl group, a halogenated alkyl group, an alkoxyalkyl group, a hydroxyalkyl group, an aminoalkyl group, a tetrahydrofurfuryl group, and a glycidyl group; And ester compounds of polyhydric alcohols such as alkylene glycol, polyoxyalkylene glycol, (alkyl / allyloxy) polyalkylene glycol and trimethylolpropane.

  The organic compound (c) having a polymerizable unsaturated group can be selected from one or more compounds depending on the purpose. For example, when a cylindrical printing original plate is used as a printing plate, a long-chain aliphatic, alicyclic, or aromatic is used as the organic compound (c) in order to suppress swelling with respect to an organic solvent such as alcohol or ester as a printing ink solvent. It is preferable to select at least one kind of group derivative.

  In order to increase the mechanical strength of the cured resin, it is preferable to select at least one compound having a substituent (functional group) such as an alicyclic group or an aromatic group as the organic compound (c). The compound having a substituent such as an alicyclic group or an aromatic group is preferably 20% by mass or more and 100% by mass or less, more preferably 50% by mass or more and 100% by mass with respect to the total amount of the organic compound (c). It is as follows.

  The sheet-like resin in the present embodiment may be a photosensitive resin composition or a photosensitive resin cured product, and preferably contains a photopolymerization initiator in the photosensitive resin composition.

[Photopolymerization initiator]
As light at the time of photocuring the photosensitive resin composition, high energy rays such as ultraviolet rays, visible rays, electron beams, and X-rays can be used.
When photocuring using ultraviolet rays or visible light, it is preferable to add a photopolymerization initiator to the photosensitive resin composition. Examples of the photopolymerization initiator include a hydrogen abstraction type photopolymerization initiator (d) and / or a decay type photopolymerization initiator (e).

[Hydrogen extraction type photopolymerization initiator (d)]
Although it does not specifically limit as a hydrogen abstraction type photoinitiator (d), An aromatic ketone can be mentioned.
An aromatic ketone is efficiently brought into an excited triplet state by photoexcitation. As this excited triplet state, a chemical reaction mechanism has been proposed in which hydrogen is extracted from the surrounding medium to generate radicals. The generated radical is considered to be involved in the photocrosslinking reaction.

The hydrogen abstraction type photopolymerization initiator (d) is not particularly limited as long as it is a compound that generates radicals by extracting hydrogen from a 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 the group consisting of the aforementioned compounds.

Examples of benzophenones include benzophenone and derivatives thereof. Specifically, 3,3 ′, 4,4′-benzophenone tetracarboxylic anhydride, 3,3 ′, 4,4′-tetramethoxybenzophenone, etc. Can be mentioned.
Examples of Michler ketones include Michler ketone and derivatives thereof.
Examples of xanthenes include xanthene and derivatives substituted with an alkyl group, a phenyl group, or a halogen group.
Examples of thioxanthones include thioxanthone and derivatives substituted with an alkyl group, a phenyl group, and a halogen group. Specific examples include ethylthioxanthone, methylthioxanthone, and chlorothioxanthone.
Examples of anthraquinones include anthraquinone and derivatives substituted with an alkyl group, a phenyl group, or a halogen group.

The addition amount of the hydrogen abstraction type photopolymerization initiator (d) is preferably 0.3% by mass or more and 10% by mass or less, more preferably 0.5% by mass or more and 5% by mass with respect to the total amount of the photosensitive resin composition. % Or less.
If the addition amount of the hydrogen abstraction type photopolymerization initiator (d) is within the above range, when the photosensitive resin composition is photocured in the atmosphere, the curability of the cured product surface can be sufficiently secured, and As a cured product, cracks and the like are not generated on the surface during long-term storage, and weather resistance can be ensured.

"Collapse photopolymerization initiator (e)"
The collapsible photopolymerization initiator (e) means a compound that generates an active radical by generating a cleavage reaction in the molecule after light absorption, and is not particularly limited.
Specifically, benzoin alkyl ethers, 2,2-dialkoxy-2-phenylacetophenones, acetophenones, acyloxime esters, azo compounds, organic sulfur compounds, acylphosphine oxides, diketones, etc. Can be mentioned.
As the collapsible photopolymerization initiator (e), it is preferable to use at least one compound selected from the group consisting of the aforementioned compounds.

Examples of benzoin alkyl ethers include benzoin isopropyl ether and benzoin isobutyl ether.
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, and 2,2-diethoxyacetophenone.
Examples of acyloxime 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 diketones include benzyl and methylbenzoyl formate.

The addition amount of the collapsible photopolymerization initiator (e) is preferably 0.3% by mass or more and 10% by mass or less, more preferably 0.5% by mass or more and 5% by mass based on the total amount of the photosensitive resin composition. It is as follows.
If the addition amount of the collapsible photopolymerization initiator (e) is within the above 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.
Examples of the photopolymerization initiator include α-aminoacetophenones.
Examples of α-aminoacetophenones include 2-methyl-1- (4-methylthiophenyl) -2-morpholino-propan-1-one and 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -Butanone etc. can be mentioned.

The addition amount of the photopolymerization initiator 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 0.3% by mass of the total amount of the photosensitive resin composition. The content is preferably 10% by mass or less, more preferably 0.5% by mass or more and 3% by mass or less.
If the addition amount of the photopolymerization initiator is within the above range, the mechanical properties of the cured product can be sufficiently ensured even when the photosensitive resin composition is photocured in the atmosphere.

[Photoacid generator, photobase generator]
A photoacid generator or photobase generator that generates an acid or a base by light irradiation can be used as a photopolymerization initiator.
By using a photoacid generator or a photobase generator, a compound having a functional group that undergoes a ring-opening polymerization reaction, such as an epoxy compound or an oxetane compound, can be subjected to ring-opening polymerization.

  The sheet-like resin in the present embodiment may be a thermosetting resin composition or a thermosetting resin cured product, and preferably contains a thermal polymerization initiator in the thermosetting resin composition.

[Thermal polymerization initiator]
As thermal polymerization initiators, suitable compounds are all thermal polymerization initiators that can be used in radical polymerization reactions or ring-opening polymerization reactions.
Examples of the thermal polymerization initiator used in the radical polymerization reaction include organic peroxides, inorganic peroxides, organic silicon peroxides, hydroperoxides, azo compounds, thiol compounds, phenol resins, amino resins, halogen compounds, and aldehydes. A compound etc. can be mentioned.
Examples of the thermal polymerization initiator used in the ring-opening polymerization reaction include a latent thermal polymerization initiator in which a thermal polymerization initiator is placed in a microcapsule.

The thermal polymerization initiator is preferably liquid at 20 ° C. from the viewpoint of easy mixing with the resin (b) or the organic compound (c).
The content of the thermal polymerization initiator is preferably 0.1% by mass or more and 10% by mass or less with respect to the total amount of the thermosetting resin composition. The content of the thermal polymerization initiator is more preferably 0.5% by mass or more and 5% by mass or less, and further preferably 1% by mass or more and 5% by mass or less.
If the content of the thermal polymerization initiator is within the above range, the thermosetting resin composition can be sufficiently cured, and the tackiness of the surface of the thermosetting product can be reduced.

In the present embodiment, selection of a thermal polymerization initiator is important in order to perform thermal polymerization suitably. The thermal stability of the thermal polymerization initiator is usually free by the 10 hour half-life temperature (10 h-t1 / 2), ie 50% of the initial amount of thermal polymerization initiator decomposes after 10 hours. Indicated at the temperature at which the radical is formed.
Details regarding the 10-hour half-life temperature are given in “Encyclopedia of Polymer Science and Engineering”, Volume 11, p. 1 and later, John Wiley & Sons, New York, 1988.
The 10-hour half-life temperature of the thermal polymerization initiator is preferably at least 60 ° C, more preferably at least 70 ° C, and even more preferably 80 ° C to 150 ° C.

As the thermal polymerization initiator, an organic peroxide is particularly preferable from the viewpoint of thermosetting and compatibility with the thermosetting resin composition.
Examples of the thermal polymerization initiator include t-butyl peroctanoate, t-amyl peroctanoate, t-butyl peroxyisobutyrate, t-butyl peroxymaleate, t-amyl perbenzoate, di-peroxyphthalate di- Peroxyesters such as t-butyl, t-butyl perbenzoate, t-butyl peracetate, and 2,5-di (benzoylperoxy) -2,5-dimethylhexane; 1,1-di (t-amylperoxy) ) Diperoxyketals such as cyclohexane, 1,1-di (t-butylperoxy) cyclohexane, 2,2-di (t-butylperoxy) butane, and ethyl 3,3-di (t-butylperoxy) butyrate; Di-t-butyl peroxide, t-butyl cumyl peroxide, dicumyl peroxide, and 2,5-di (t-butyl peroxide) Dialkyl peroxides such as dibenzoyl peroxide and diacetyl peroxide; t such as t-butyl hydroperoxide, t-amyl hydroperoxide, pinane hydroperoxide, and cumyl hydroperoxide -Alkyl hydroperoxides can be mentioned.

As a thermal polymerization initiator, an azo compound can be mentioned as a preferable compound when forming a cushion layer containing bubbles.
Examples of the azo compound include 1- (t-butylazo) formamide, 2- (t-butylazo) isobutyronitrile, 1- (t-butylazo) cyclohexanecarbonitrile, 2- (t-butylazo) -2-methylbutane. Nitriles, 2,2′-azobis (2-acetoxypropane), 1,1′-azobis (cyclohexanecarbonitrile), 2,2′-azobis (isobutyronitrile), and 2,2′-azobis (2- Methylbutanenitrile) and the like.

[Fine particles]
Inorganic fine particles, organic fine particles, and / or organic-inorganic composite fine particles can be added to the resin composition. Improvement of mechanical properties of cured resin obtained by curing by adding these fine particles, improvement of wettability of resin cured product surface, adjustment of viscosity of resin composition, viscoelastic properties of cured resin Adjustment and the like are possible.
The material of the inorganic fine particles or organic fine particles is not particularly limited, and known fine particles can be used.
Examples of the organic / inorganic composite fine particles include fine particles in which an organic layer or organic fine particles are formed on the surface of inorganic fine particles, or fine particles in which an inorganic layer or inorganic fine particles are formed on the surface of organic fine particles.

As the fine particles, for the purpose of improving the mechanical properties of the cured resin, inorganic fine particles having high rigidity such as silicon nitride, boron nitride, and silicon carbide, or organic fine particles such as polyimide can be used.
In order to improve the solvent resistance of the obtained resin cured product, inorganic fine particles or organic fine particles formed of a material having a good swelling property in the solvent to be used can be added.

  For the purpose of forming a pattern that penetrates the surface of the resin cured product layer or the resin cured product by laser engraving, inorganic porous fine particles with excellent adsorption and removal characteristics of viscous liquid residue generated during laser engraving can be added. Good.

  The fine particles are not particularly limited, and examples thereof include porous silica, mesoporous silica, silica-zirconia porous gel, porous alumina, and porous glass.

  It is preferable that the number average particle diameter of the fine particles is 0.01 to 100 μm. The number average particle diameter of the fine particles is preferably 0.1 to 20 μm, more preferably 1 to 10 μm. When fine particles having a number average particle size within the above range are used, there are inconveniences such as increase in viscosity, entrainment of bubbles, and generation of a large amount of dust when mixing with the resin (b) and the organic compound (c). As a result, unevenness does not occur on the surface of the cured resin.

  In the present embodiment, the average particle size of the fine particles means a value measured using a laser scattering type particle size distribution measuring device.

  The particle shape of the fine particles is not particularly limited, and as the fine particles, spherical, flat, needle-shaped, amorphous, or particles having protrusions on the surface can be used, and from the viewpoint of wear resistance, Spherical particles are preferred.

The surface of the fine particles can be coated with a silane coupling agent, a titanium coupling agent, and other organic compounds and subjected to a surface modification treatment to use finer particles that are made more hydrophilic or hydrophobic.
In the present embodiment, one kind or two or more kinds of these fine particles can be selected.

[Composition ratio of resin composition]
The ratio of the resin (b), the organic compound (c), and the fine particles in the resin composition is preferably 5 to 200 parts by mass of the organic compound (c) with respect to 100 parts by mass of the resin (b). More preferably, it is 100 parts by mass.
The fine particles are preferably 1 to 100 parts by mass, more preferably 2 to 50 parts by mass, and further preferably 2 to 20 parts by mass with respect to 100 parts by mass of the resin (b).
When the ratio of the organic compound (c) is within the above range, it is easy to balance the hardness and tensile strength / elongation of the resulting resin cured product, and the shrinkage at the time of curing is within a small range to ensure thickness accuracy. Can do.

  A polymerization inhibitor, an ultraviolet absorber, a lubricant, a surfactant, a plasticizer, a fragrance, and the like can be added to the resin composition according to the use and purpose.

[Method for producing sheet-like resin]
As a method for producing the sheet-like resin, an existing resin molding method can be used.
Sheet resin production methods include, 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, a method of adjusting the thickness with a blade, a method of adjusting a thickness by calendaring with a roll, a spray, and the like The method of spraying using can be mentioned.
When the sheet-like resin is molded, it is possible to perform the molding while heating in a range that does not cause thermal decomposition, and rolling treatment, grinding treatment, and the like may be performed as necessary.

[Photocuring method]
The molded photosensitive resin composition is crosslinked by light irradiation to form a cured photosensitive resin.
While forming the photosensitive resin composition, it can be crosslinked by irradiation with light to form a cured photosensitive resin.
Examples of the light source used for photocuring 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 irradiated to the photosensitive resin composition preferably has light having a wavelength of 200 nm to 400 nm.
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 400 nm, sufficiently ensure the curability of the surface of the photosensitive resin cured product. Can do. The light source used for photocuring may be one type, but since the curability of the resin may be improved by curing using two or more types of light sources having different wavelengths, two or more types of light sources may be used. preferable.

[Thermosetting method]
When the curable resin composition is a thermosetting resin composition, a thermosetting resin cured product is obtained by heat treatment.
Examples of the heating method include a method of irradiating infrared rays, a method of exposing to an atmosphere heated by an oven, a method of contacting an object such as a heated metal, and the like. The heating temperature is selected according to the type of thermal polymerization initiator.

[Cushion layer]
In the present embodiment, the surface adjustment layer may also serve as a cushion layer, and a cushion layer made of an elastomer can be formed below the sheet-like resin (on the side in contact with the cylindrical support (a)). In addition, a cushion layer may be formed on the surface of the cylindrical support (a).
The cushion layer is preferably an elastomer layer having a Shore A hardness of 10 to 70 degrees, or an ASKER-C hardness of 20 to 85 degrees measured with an ASKER-C hardness meter.
When the Shore A hardness is 10 degrees or more, or the ASKER-C hardness is 20 degrees or more, the print quality can be ensured because it is appropriately deformed.
When the Shore A hardness is 70 degrees or less or the ASKER-C hardness is 85 degrees or less, it can serve as a cushion layer.
It is preferable that the Shore A hardness is 20 to 60 degrees or the ASKER-C hardness is 45 to 75 degrees. The Shore A hardness and the ASKER-C hardness are preferably selected depending on the material used for the cushion layer. The difference between the two types of hardness stems from the difference in the shape of the pushers of the hardness meter used for measurement. In the case of a uniform resin composition, it is preferable to use Shore A hardness, and in the case of a non-uniform resin composition such as a foamable base material such as foamed polyurethane and foamed polyethylene, it is preferable to use ASKER-C hardness. ASKER-C hardness is a measuring method based on JIS K7312 standard.

The material for the cushion layer is not particularly limited, and examples thereof include elastomers having rubber elasticity such as thermoplastic elastomers, photocurable elastomers, and thermosetting elastomers.
From the viewpoint of processability to a 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 an elastomer after curing.

  The cushion layer preferably contains a cured resin and contains bubbles or organic fine particles. It is preferable to use organic microparticles that are hollow microcapsules, in which inorganic microparticles are attached to the surface of the hollow microcapsules. The average particle diameter of the organic fine particles is preferably 1 μm or more and 500 μm or less, more preferably 10 μm or more and 300 μm or less, and further preferably 80 μm or more and 200 μm or less.

The density of the cushion layer is preferably 0.1 g / cm ³ or more and 0.9 g / cm ³ or less, more preferably 0.3 g / cm ³ or more and 0.7 g / cm ³ or less, and still more preferably 0. .4g / cm ³ or more 0.6g / cm ³ or less.
If the density of the cushion layer is within the above range, the impact applied to the laser engraving layer in the printing process can be sufficiently absorbed.

  Examples of the thermoplastic elastomer used for the cushion layer include styrene thermoplastic elastomers such as SBS (polystyrene-polybutadiene-polystyrene), SIS (polystyrene-polyisoprene-polystyrene), and SEBS (polystyrene-polyethylene / polybutylene-polystyrene), Examples include olefin-based thermoplastic elastomers, urethane-based thermoplastic elastomers, ester-based thermoplastic elastomers, amide-based thermoplastic elastomers, silicon-based thermoplastic elastomers, and fluorine-based thermoplastic elastomers.

  The photocurable elastomer used for the cushion layer is a composition in which a thermoplastic elastomer is mixed with a photopolymerizable monomer, a plasticizer, a photopolymerization initiator, etc., and a liquid resin is mixed with a photopolymerizable monomer, a photopolymerization initiator, etc. And the like.

  The elastomer used for the cushion layer may be a sulfur cross-linked rubber, organic peroxide, phenol resin initial condensate, quinone dioxime, metal oxide, and non-sulfur cross-linked rubber using a compound such as thiourea as a cross-linking agent. . It is also possible to use an elastomer obtained by three-dimensional crosslinking using a curing agent that reacts with telechelic liquid rubber.

  The cushion layer may be a cushion layer made of foamed polyurethane, foamed polyethylene or the like and having independent or open cells in the layer, and commercially available cushion materials and cushion tapes can also be used. An adhesive or a pressure-sensitive adhesive may be applied to one side or both sides of the layer.

By forming a modified layer on the surface of the photosensitive resin cured product of the present embodiment, tack on the surface of the printing substrate can be reduced and 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. Groups, trichlorosilyl groups, diethoxysilyl groups, dimethoxysilyl groups, dimonochlorosilyl groups, monoethoxysilyl groups, monomethoxysilyl groups, and monochlorosilyl groups.
At least one of these functional groups exists in the molecule, and is immobilized on the surface of the substrate by reacting with the surface hydroxyl group of the substrate.

  The compound constituting the silane coupling agent is selected from the group consisting of 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. A compound having at least one functional group or a compound having a long-chain alkyl group can be used.

[Laser engraving]
In the present embodiment, when the cured resin is used as a printing substrate on which a pattern is formed by using a laser engraving method, the laser engraving method uses a computer as a digital data to form an image to be formed. To create a relief image on the printing substrate. Any laser beam may be used for the laser engraving as long as the original plate includes a wavelength having absorption. However, in order to perform engraving at a high speed, a laser beam having a high output is preferable. And infrared or infrared emitting solid lasers such as YAG lasers and semiconductor lasers.
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 organic Ablation processing that cuts the bond of molecules is possible, and it is suitable for fine processing. The laser may be continuous irradiation or pulse irradiation.

[How to remove laser engraving residue]
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.

[Laser engraved cylindrical printing plate surface treatment]
In this embodiment, after engraving to form a concave pattern by irradiating laser light, 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 Post-exposure by irradiating with 450 nm light can also be performed. This is an effective method for 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 treated and 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 drawing-type photoinitiator.

[Usage]
Examples of the use of the cylindrical printing original plate for laser engraving manufactured by the manufacturing method of the present embodiment include a printing original plate or a printing plate used in printing techniques such as flexographic printing, dry offset printing, and gravure printing. Narrow webs such as flexographic label printing, which require a highly accurate printed matter, and curved offset printing such as can offset printing and tube printing are preferred applications.

In printing, when the ink contains an aliphatic hydrocarbon and / or an aromatic hydrocarbon, the sheet-like resin preferably contains a polycarbonate, polyurethane, polyamide, polyvinyl alcohol, or vinyl alcohol-vinyl acetate copolymer. These resin materials are preferable because they have resistance to the above-mentioned solvents.
Examples of aliphatic hydrocarbons include compounds such as hexane, heptane, octane, nonane, decane, cyclohexane, methylcyclohexane, cyclooctane, cyclodecane, dipentene, rubber volatile oil, mineral spirits, and high boiling point petroleum solvent (ink oil). Can do.
Aromatic hydrocarbons include compounds such as toluene, xylene, dimethylbenzene, dichlorobenzene, solvent naphtha, and tetralin.

  Hereinafter, the present embodiment will be described more specifically with reference to examples and comparative examples. However, the present embodiment is not limited to only these examples. The measurement method and the evaluation method used in this embodiment are as follows.

[Measuring method]
(1) Laser engraving Laser engraving is a carbon dioxide laser engraving machine (UK, ZED, ZED-mini-1000; USA, Coherent, output 250W carbon dioxide laser, laser oscillation wavelength is 10.6 μm) Used. Engraving was performed by creating a dot pattern (120 lines / inch, area ratio 10%). The engraving depth was 0.55 mm.

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

(3) Measurement of number average molecular weight The number average molecular weights of the resin (b) and the organic compound (c) were determined by conversion with polystyrene having a known molecular weight using a gel permeation chromatography method (GPC method). Using a high-speed GPC device (manufactured by Tosoh Corporation, HLC-8020) and a polystyrene-filled column (manufactured by Tosoh Corporation, TSKgel GMHXL), measurement was carried out by developing with tetrahydrofuran. The column temperature was set to 40 ° C. As a sample to be injected into the GPC apparatus, a tetrahydrofuran solution having a resin concentration of 1% by mass was prepared, and the injection amount was 10 μL. A differential refractometer was used as the detector.

(4) Measurement of ten-point average surface roughness Rz Using a surface roughness measuring device “SE500” manufactured by Kosaka Laboratory, stylus R (radius of curvature) 2 μm, cutoff λc = 0.8 mm, measurement length Measurement was performed under conditions of 4 mm and a feed rate of 0.5 m / sec, and a ten-point average surface roughness Rz was measured.

Example 1
As resin (b), 70 parts by mass of polycarbonate polyurethane having a number average molecular weight of approximately 100,000 (manufactured by Dainichi Seika Co., Ltd., “Resamine (registered trademark) P890”), and as organic compound (c), phenoxyethyl methacrylate (molecular weight 190) 30 parts by mass and 1 part by mass of trimethylolpropane triacrylate (molecular weight 338), as fine particles, porous fine powder silica (manufactured by Fuji Silysia Chemical Co., Ltd., “Cyrossphere (registered trademark) C-1504”, number average particle diameter 4 0.5 μm, 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, the same applies hereinafter.) 5 parts by mass, photopolymerization initiator As 0.5 parts by weight of benzophenone and 0.6 parts by weight of 2,2-dimethoxy-2-phenylacetophenone, stable As the 2,6-di -t- butyl-acetophenone 0.5 part by weight, a kneader (Moriyama Co., "D1-5") and mixed at 130 ° C. was used to adjust the photosensitive resin composition. Using the biaxial extrusion device (“KZW-TW”, manufactured by Technobel Co., Ltd.), the obtained photosensitive resin composition is a PET film having a thickness of 50 μm (manufactured by Toray Industries, Inc.) on which the urethane adhesive is thinly applied. The sheet-like resin was formed by sandwiching it with a cover sheet (manufactured by Fujimori Kogyo Co., Ltd.) having a thickness of 50 μm which was extruded with a thickness of 0.4 mm and further subjected to silicone release treatment. The photosensitive resin composition of sheet-like resin was solid at 20 ° C.
The obtained sheet-like resin was cut into a width of 180 mm and a length of 710 mm. A type in which the cover film is peeled off and cured with moisture in the air on a fiber reinforced plastic sleeve (made by AKL, Germany) with an inner diameter of 226.12 mm, a thickness of 0.45 mm, and a width of 200 mm attached to the air cylinder. Of anaerobic adhesive (manufactured by ThreeBond, “TB-1530”) was applied at a thickness of 0.1 mm and left for 10 minutes. The sheet-like resin was wound on the resin, a polyethylene heat-shrinkable tube was covered on the outside, and the resin was shrunk using an infrared heater (Ushio Corp., “UH-USF-CL300”). The temperature of the polyethylene surface was about 100 ° C. The fiber reinforced plastic sleeve used was made of epoxy resin reinforced with glass cloth. The thickness of the glass cloth was about 50 μm. The surface of the hollow cylindrical support had irregularities due to grinding with a grindstone, and the ten-point average surface roughness Rz was about 5 μm. The ten-point average surface roughness Rz after applying the anaerobic adhesive to form the surface adjustment layer was 0.5 μm, and the irregularities were covered.
When measuring the light of a metal halide lamp (“F450V type UV lamp” manufactured by Fusion, Inc.) while rotating the air cylinder using a light amount measuring device (“M02 + UV35” manufactured by Oak Manufacturing Co., Ltd.) having a central wavelength of sensitivity at 350 nm. To 4000 mJ / cm ² , the photosensitive resin composition was photocured to obtain a cylindrical printing original plate.
The Shore D hardness of the cured photosensitive resin was 50 degrees. Moreover, the outer diameter of the obtained cylindrical printing original plate was measured about five places using the laser length measuring device. At each location, the cylinder was rotated once to measure the deviation of the outer diameter. The outer diameter accuracy was within ± 20 μm.
An uneven pattern was formed on the surface of the obtained cylindrical printing original plate for laser engraving using a carbon dioxide laser engraving machine. Eight cylindrical printing plates having a pattern formed on the surface were prepared and set in a dry offset can printing machine (manufactured by Stora Machinery Inc., USA), and eight colors were printed on the surface of the aluminum can. The time required for the operation of attaching the cylindrical printing plate to the air cinder and performing the alignment was within 2 minutes per one. Compared with the time (about 20 minutes per one) required for the operation of attaching and aligning the conventional sheet plate, the time was significantly reduced. Printing on aluminum cans was performed at a speed of 25 lines per second. It was confirmed that the surface of the aluminum can was printed with good print quality. Even after printing 1 million copies, there was no particular problem in durability.

(Example 2)
As the resin (b), 70 parts by mass of a styrene-butadiene-styrene block copolymer having a number average molecular weight of about 100,000, 15 parts by mass of liquid polybutadiene having a number average molecular weight of 2000, an alicyclic hydrocarbon plasticizer (Shin Nippon Petrochemical Co., Ltd.) 10 parts by mass of “B2000” manufactured by the company, 10 parts by mass of hexamethylene diacrylate (molecular weight 254) as the organic compound (c), and porous fine powder silica (manufactured by Fuji Silysia Chemical Co., Ltd. (Registered trademark) C-1504 ") 5 parts by weight, 0.5 parts by weight of benzophenone and 0.6 parts by weight of 2,2-dimethoxy-2-phenylacetophenone as a photopolymerization initiator, -0.5 part by mass of t-butylacetophenone was mixed at a temperature of 130 ° C using a kneader ("D1-5", manufactured by Moriyama Co., Ltd.), and photosensitive. To prepare a fat composition. Using the biaxial extrusion device (“KZW-TW”, manufactured by Technobel Co., Ltd.), the obtained photosensitive resin composition is a PET film having a thickness of 50 μm (manufactured by Toray Industries, Inc.) on which the urethane adhesive is thinly applied. The sheet-like resin was formed by sandwiching it with a cover sheet (manufactured by Fujimori Kogyo Co., Ltd.) having a thickness of 50 μm which was extruded with a thickness of 0.4 mm and further subjected to silicone release treatment. The photosensitive resin composition of sheet-like resin was solid at 20 ° C.
In the same manner as in Example 1, a cylindrical printing original plate was obtained. The Shore D hardness of the sheet-form printing original plate was 25 degrees. The outer diameter accuracy of the cylindrical printing original plate was within ± 20 μm.
Thereafter, a cylindrical printing plate was produced in the same manner as in Example 1.
The obtained cylindrical printing plate was set in a flexographic printing machine (manufactured by Iyo Machinery Co., Ltd.) having a metal cylinder with an outer diameter of 226.12 mm, and printing was performed on the surface of the polyethylene film. The installation of the cylindrical printing plate on the plate cylinder of the printing press could be carried out within 2 minutes.

(Example 3)
The sheet-like resin produced in Example 1 was placed on a glass flat plate, and ultraviolet rays emitted from a chemical lamp (“10R”, manufactured by Philips, Lankoku) from both sides were 4000 mJ / cm ² (integrated light quantity at 350 nm). ) Irradiated to form a sheet-like resin.
The obtained sheet-like resin was cut into a width of 180 mm and a length of 710 mm. An anaerobic adhesive (manufactured by Three Bond Co., “TB-1530”) on a fiber reinforced plastic sleeve (manufactured by AKL, Germany) having an inner diameter of 226.12 mm, a thickness of 0.45 mm, and a width of 200 mm attached to the air cylinder. It was applied at a thickness of 0.1 mm and left for 10 minutes. The sheet-like resin was wound thereon, both ends were fixed with tape, and left for 1 hour. Moreover, the outer diameter of the obtained cylindrical printing original plate was measured about five places using the laser length measuring device. The outer diameter accuracy was ± 15 μm. The fiber reinforced plastic sleeve was a woven fabric reinforced with aramid fibers and woven with yarn having a fiber diameter of 10 μm. Irregularities having a 10-point average surface roughness Rz of 10 μm were not visually observed by the anaerobic adhesive used as the surface adjustment layer.
An uneven pattern was formed on the surface of the obtained laser engraved cylindrical printing original plate using a carbon dioxide laser engraving machine, and used for dry offset printing in the same manner as in Example 1.

Example 4
Into a 1 L separable flask equipped with a thermometer, a stirrer, and a reflux condenser, 447.24 parts by mass of polycarbonate diol (manufactured by Asahi Kasei Corporation, “PCDL (registered trademark) L4672”, number average molecular weight 1990, OH number 56.4) After adding 30.83 parts by mass of tolylene diisocyanate and reacting at 80 ° C. for about 3 hours under heating, 14.83 parts by mass of 2-methacryloyloxyisocyanate is added and further reacted for about 3 hours. A resin (A) having a number average molecular weight of about 10,000, which is a methacrylic group (average of about 2 polymerizable unsaturated groups in the molecule) was produced. This resin was in the shape of a syrup at 20 ° C., flowed when an external force was applied, and did not recover its original shape even when the external force was removed.
Resin (b): 70 parts by mass of resin (a); Organic compound (c): 10 parts by mass of phenoxyethyl methacrylate (molecular weight 190); Polypyrene glycol monomethacrylate (molecular weight 400): 10 parts by mass; Fine powdered silica (manufactured by Fuji Silysia Chemical Co., Ltd., “Cyrossphere C-1504”), as photopolymerization initiator, 0.5 parts by mass of benzophenone and 2,2-dimethoxy-2-phenylacetophenone 0.6 A photosensitive resin composition in which 0.5 parts by mass of 2,6-di-t-butylacetophenone was mixed as a part by mass and a stabilizer was prepared.
The obtained photosensitive resin composition was liquid at 20 ° C. The viscosity measured using a B-type viscometer was 1200 Pa · s at 20 ° C.
The prepared liquid photosensitive resin composition was applied on a 50 μm-thick PET film (manufactured by Toray Industries, Inc.) placed on a surface-polished stainless steel plate to a thickness of 0.4 mm, and a chemical lamp (Rankoku, Philips) from above and below. (10R)) was irradiated with 4000 mJ / cm ² (integrated light quantity at 350 nm) to obtain a sheet-like resin. A cylindrical printing original plate was produced in the same manner as in Example 3 except that the obtained sheet resin was used.
The accuracy of the outer diameter of the obtained cylindrical printing original plate was ± 15 μm.
Although printing was performed on the surface of the aluminum can in the same manner as in Example 1, no particular problem occurred in terms of print quality.

(Example 5)
Materials other than using an anaerobic adhesive (manufactured by ThreeBond, “TB-1530”), a photo-curing adhesive (manufactured by Notape Kogyo Co., “Acrytac (registered trademark)”) A cylindrical printing original plate was produced in the same manner. Instead of applying the anaerobic adhesive in Example 1 and leaving it for 10 minutes, a photo-curing adhesive (manufactured by No-Tape Kogyo Co., Ltd., “Acrytac (registered trademark)”) was applied, and the sheet resin was immediately cylindrical. The cylindrical printing original plate was produced in the same process as Example 1 except having passed the process wound around a shape support.
The accuracy of the outer diameter of the obtained cylindrical printing original plate was ± 15 μm.
Although printing was performed on the surface of the aluminum can in the same manner as in Example 1, no particular problem occurred in terms of print quality.

(Example 6)
As resin (b), 70 parts by mass of resin (a), as organic compound (c), 20 parts by mass of phenoxyethyl methacrylate (molecular weight 206) and 10 parts by mass of polypyrene glycol monomethacrylate (molecular weight 400), as a thermal polymerization initiator , T-butyl peroxy-2-ethylhexyl carbonate (“Perbutyl E (registered trademark)” manufactured by NOF Corporation) at 70 ° C., and further, 2,6-di-t as a stabilizer. -A thermosetting resin composition was prepared by mixing 0.5 parts by mass of butylacetophenone.
The obtained thermosetting resin composition was applied to a PET cover film (manufactured by Toray Industries, Inc.) fixed on a metal plate at a thickness of 1.5 mm, and a PET film (50 μm thick manufactured by Toray Industries Inc.) was formed thereon. In addition, a metal plate was placed thereon, placed in an oven adjusted to 130 ° C., and heated for 20 minutes to form a sheet-like resin.
The obtained sheet-like resin was cut into a width of 180 mm and a length of 710 mm. An anaerobic adhesive (manufactured by Three Bond Co., “TB-1530”) on a fiber reinforced plastic sleeve (manufactured by AKL, Germany) having an inner diameter of 226.12 mm, a thickness of 0.45 mm, and a width of 200 mm attached to the air cylinder. It was applied at a thickness of 0.1 mm and left for 10 minutes. The sheet-like resin is wound on the cover film, the cover film is peeled off, and a polyethylene heat-shrinkable tube is covered on the outside in the same manner as in Example 1, and an infrared heater (UH-USF-CL300, manufactured by USHIO INC.) Is covered. )) And allowed to stand for 1 hour.
Thereafter, the heat-shrinkable tube was cut with a cutter to obtain a cylindrical printing original plate. Moreover, the outer diameter of the obtained cylindrical printing original plate was measured about five places using the laser length measuring device. The outer diameter accuracy was ± 25 μm.
A concavo-convex pattern was formed on the surface of the obtained laser engraved cylindrical printing original plate using a carbon dioxide laser engraving machine and used for flexographic printing.

(Comparative Example 1)
A glass fiber reinforced plastic sleeve having a 10-point average surface roughness Rz of 120 μm on the surface was used as a hollow cylindrical support. The same anaerobic adhesive as in Example 1 was used as the surface adjustment layer, but it was visually confirmed that the surface irregularities were not covered. In this state, a cylindrical printing original plate was produced in the same manner as in Example 1.
Voids were observed in some places between the hollow cylindrical support of the obtained cylindrical printing original plate and the sheet-like resin. The outer diameter accuracy of the cylindrical printing original plate was ± 80 μm.
The obtained cylindrical printing original plate was laser engraved to form an image pattern on the surface, and then dry offset printing was performed in the same manner as in Example 1. However, printing defects corresponding to the irregularities occurred due to the irregularities on the surface.

(Comparative Example 2)
A cylindrical printing original plate was produced in the same manner as in Comparative Example 1 except that the thickness of the anaerobic adhesive used as the surface adjustment layer was 0.3 mm. The thick part of the anaerobic adhesive is not cured, and it is mounted on an air cylinder and rotated at a linear speed of 10 m / sec in order to form an uneven pattern on the surface with a laser engraving machine. It was in a state of peeling and floating inside. The outer diameter accuracy of the cylindrical printing original plate exceeded ± 100 μm.

The present invention is suitable as a production method suitable for producing a large amount of a cylindrical printing original plate for forming an uneven pattern on the surface by laser engraving.
The method for producing a cylindrical printing original plate for laser engraving of the present invention has industrial applicability in printing fields such as flexographic printing, dry offset printing, and gravure printing.

Claims (17)

A method for producing a cylindrical printing original for laser engraving,
(1) The process of apply | coating a curable resin composition to the surface of a hollow cylindrical support body (a) in which an uneven | corrugated | grooved part exists, and forming a surface adjustment layer,
(2) A step of winding a sheet-like resin on the surface adjustment layer and bringing it into contact with the surface adjustment layer;
(3) A method for producing a cylindrical printing original plate for laser engraving, comprising a step of curing the surface adjustment layer.   The cylindrical printing for laser engraving according to claim 1, wherein in the step (3), the surface adjustment layer is cured by at least one curing method selected from the group consisting of thermosetting, photocuring, and moisture absorption curing. Production method of the original plate.   The method for producing a cylindrical printing original plate for laser engraving according to claim 1 or 2, wherein the hollow cylindrical support (a) contains a fiber-reinforced plastic.   The method for producing a cylindrical printing original plate for laser engraving according to claim 3, wherein the fiber reinforced plastic contains at least one resin selected from the group consisting of polyester, polyamide, epoxy, polyurethane, and polyimide.   The fiber-reinforced plastic contains at least one fiber selected from the group consisting of polyester fiber, polyimide fiber, polyamide fiber, polyolefin fiber, cellulose fiber, glass fiber, carbon fiber, metal fiber, and ceramic fiber. Item 5. The method for producing a cylindrical printing original plate for laser engraving according to Item 3 or 4.   The method for producing a cylindrical printing original plate for laser engraving according to claim 5, wherein the fibers are at least one type of fibers selected from the group consisting of woven fabrics, nonwoven fabrics, and knitted fabrics.   The method for producing a cylindrical printing original plate for laser engraving according to claim 5 or 6, wherein the fiber has a thickness of 10 nm or more and 50 µm or less.   The manufacturing method of the cylindrical printing original plate for laser engraving of any one of Claim 1 to 7 whose thickness of the said hollow cylindrical support body (a) is 0.1 mm or more and 2 mm or less.   The method for producing a cylindrical printing original plate for laser engraving according to any one of claims 1 to 8, wherein the ten-point average roughness Rz of the concavo-convex portion is 5 µm or more and 100 µm or less.   The method for producing a cylindrical printing original plate for laser engraving according to any one of claims 1 to 9, wherein the surface adjustment layer has a thickness of 20 µm or more and 200 µm or less.   The cylinder for laser engraving according to any one of claims 1 to 10, wherein a surface of the surface adjustment layer has adhesiveness, and a surface tack of the surface adjustment layer is 300 gf / cm or more and 2 kgf / cm or less. A method for producing a letter printing original plate.   The sheet-like resin is selected from the group consisting of polyamide, polyester, polyurethane, polycarbonate, polyether polyol, polyvinyl alcohol, vinyl alcohol-vinyl acetate copolymer, styrene-butadiene copolymer, and styrene-isoprene copolymer. The method for producing a cylindrical printing original plate for laser engraving according to any one of claims 1 to 11, comprising at least one kind of resin.   The method for producing a cylindrical printing original plate for laser engraving according to any one of claims 1 to 12, wherein the thickness of the sheet-like resin is 0.1 mm or more and 5 mm or less.   A laser engraving cylindrical printing plate comprising a laser engraving step of irradiating a laser beam to form a concave pattern on the laser engraving cylindrical printing original plate produced by the method according to any one of claims 1 to 13. Manufacturing method.   The method for producing a laser engraved cylindrical printing plate according to claim 14, wherein the laser engraved cylindrical printing plate is used in an application selected from flexographic printing, dry offset printing, and gravure printing.   A dry offset printing method for printing on a cylindrical substrate surface using the laser engraved cylindrical printing plate according to claim 15.   The dry offset printing method according to claim 16, wherein an ink containing an aliphatic hydrocarbon and / or an aromatic hydrocarbon is used.