Manufacturing method of printed matter

Abstract

To provide a manufacturing method of a printed matter capable of stably obtaining a high-quality printed matter for a long period of time, with excellent curing properties even with two or less active energy ray sources, when printing two or more kinds of active energy ray-curable compositions.SOLUTION: A manufacturing method of a printed matter includes: a printing step of printing two or more kinds of active energy ray-curable compositions onto a substrate P; and a curing step of emitting an active energy ray LB from an irradiation device 7 to cure the active energy ray-curable compositions on the substrate P. The two or more kinds of active energy ray-curable compositions include a (meth)acrylate compound. The irradiation device 7 is equipped with n pieces (n is an integer of 2 or larger) of active energy ray sources 7L. If the two or more kinds of active energy ray-curable compositions include one with an iodine value IV of lower than 100, n pieces of active energy ray sources 7L are lit and the active energy ray LB is emitted. If every iodine value IV is 100 or higher, (n-1) pieces or less of active energy ray sources 7L are lit and the active energy ray LB is emitted.SELECTED DRAWING: Figure 6A

Description

Technical Field

[0001] The present invention relates to a method for manufacturing printed matter.

Background Art

[0002] A printing method using an active energy ray curable composition is a solvent-free type and instantaneously cures and dries with active energy rays. Therefore, it is excellent in environmental compatibility and printing workability, and high-quality printed matter can be obtained. It is widely used from the field of printed information such as magazines and leaflets to the field of packages for food packaging such as paper containers.

[0003] In recent years, as an active energy ray source for curing an active energy ray curable composition, in addition to light sources such as high-pressure mercury lamps and metal halide lamps that have been conventionally used, a mercury-free metal halide lamp that does not generate ozone is used to generate ultraviolet rays of 230 to 420 nm, and light emitting diodes that generate ultraviolet rays in the range of a light emission peak wavelength of 350 to 420 nm are used. UV-LEDs and other various types of light sources are used. On the other hand, since a light source converts electric power into light, there is a limit to the output per light source due to its conversion efficiency and the influence of generated heat. In general, a plurality of light sources are arranged and used according to the required amount of light.

[0004] In particular, when using an active energy ray-curable composition containing a photoinitiator, in order to fully function the photoinitiator and to compensate for the reduction in surface curability due to the inhibition of radical reaction by oxygen in the air, it is common to use three or more light sources arranged side by side in the curing process of the printing line. However, using a large number of light sources has problems such as increased introduction costs, maintenance costs, and energy costs, as well as damage to the printed matter due to heat. Further, when three or more light sources are used, only the surface of the printed matter may be excessively cured, and cracks, wrinkles, etc. may occur in the cured product of the composition. Also, in a printing method using a transfer roll during printing, the roll temperature greatly affects the transferability of the composition, but increasing the number of lamps may cause the roll temperature to rise due to the heat from the lamps, resulting in deterioration of print quality. In this case, measures such as cooling the roll are necessary.

[0005] Furthermore, in recent years, there has been an increasing demand for labor saving, labor reduction, automation, and high speed during printing. The printing speed has been increasing more and more, and it is common to ensure curability by increasing the number of lamps. And, a composition that can stably obtain high-quality printed matter without trouble over a long period of time under various printing conditions is desired. Among them, when printing for a long time using two or more compositions, it is important that the dot gain, which is a change in the dot diameter of the composition, does not increase in order to obtain a clear printed matter.

[0006] In particular, in packages for filling beverages, confectionery, food containers, pouches and containers with lids, packaging containers such as cups and trays, and books such as comics, art, history, study reference books, specialized books, science, and photo albums, design is emphasized, and a printing method that does not cause problems such as clear image formation and blocking is important.

[0007] As an active energy ray-curable composition used for such printing and a printed matter using the composition, Patent Document 1 discloses a composition of a combination of a photopolymerization initiator and a diallyl phthalate resin and a printed matter using the composition, but there is no description of a method for manufacturing a high-quality printed matter using a plurality of compositions with a small number of lamps.

[0008] Further, Patent Document 2 discloses an improvement in the curability of an active energy ray-curable composition depending on a photopolymerization initiator composition, but there is no description of a method for manufacturing a high-quality printed matter using a plurality of compositions with a small number of lamps.

Prior Art Documents

Patent Documents

[0009]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0010] When using two or more active energy ray-curable compositions, the present invention provides a method for manufacturing a printed matter, which has excellent curability even when the number of active energy ray sources for generating active energy rays is two or less, and can stably obtain a high-quality printed matter for a long time.

Means for Solving the Problems

[0011] As a result of intensive studies to solve the above problems, the present inventors have found that the above problems can be solved by the following method for manufacturing a printed matter, and have completed the present invention.

[0012] 1) That is, the present invention relates to a method for manufacturing a printed matter, including: a printing step of printing two or more kinds of active energy ray-curable compositions on a substrate P using a transfer roll 8 respectively; and a curing step of irradiating active energy ray LB from an active energy ray irradiating device 7 after the printing step to cure the active energy ray-curable compositions printed on the substrate P. The two or more kinds of active energy ray-curable compositions contain a (meth)acrylate compound. When the active energy ray irradiating device 7 is equipped with n (n is an integer of 2 or more) active energy ray sources 7L and there is a composition among the two or more kinds of active energy ray-curable compositions with an iodine value IV of less than 100, all n active energy ray sources are lit to irradiate the active energy ray LB. When the iodine value IV of all the two or more kinds of active energy ray-curable compositions is 100 or more, (n - 1) or less of the n active energy ray sources 7L are lit to irradiate the active energy ray LB. 2) Further, the present invention relates to a method for manufacturing a printed matter, including: a printing step of printing two or more kinds of active energy ray-curable compositions on a substrate P using a transfer roll 8 respectively; and a curing step of irradiating active energy ray LB from an active energy ray irradiating device 7 after the printing step to cure the active energy ray-curable compositions printed on the substrate P. The two or more kinds of active energy ray-curable compositions contain a (meth)acrylate compound. The active energy ray irradiating device 7 is capable of being equipped with n (n is an integer of 2 or more) active energy ray sources 7L. When there is a composition among the two or more kinds of active energy ray-curable compositions with an iodine value IV of less than 100, n active energy ray sources 7L are mounted on the active energy ray irradiating device 7 to irradiate the active energy ray LB. When the iodine value IV of all the two or more kinds of active energy ray-curable compositions is 100 or more, (n - 1) or less of the n active energy ray sources 7L are mounted on the active energy ray irradiating device 7 to irradiate the active energy ray LB. The present invention also relates to the method for manufacturing a printed matter according to 1) above, which adjusts the amount of energy irradiated to the active energy ray-curable composition by the number of lit active energy ray sources 7L. The present invention also relates to the method for manufacturing the printed matter according to 2) above, which adjusts the amount of energy irradiated to the active energy ray-curable composition according to the number of active energy ray sources 7L mounted. The present invention also relates to the method for manufacturing the printed matter according to 1) or 2) above, wherein the number is (n - 1) or less and 2 or less.

[0013] The present invention also relates to the method for manufacturing the printed matter according to 1) or 2) above, wherein all of the two or more active energy ray-curable compositions have an iodine value IV of 110 or more and 220 or less.

[0014] The present invention also relates to the method for manufacturing the printed matter according to 1) or 2) above, wherein the surface temperature of the transfer roll 8 during printing is 16 to 40°C.

[0015] The present invention also relates to the method for manufacturing the printed matter according to 1) or 2) above, wherein the active energy ray-curable composition contains a photoinitiator.

[0016] The present invention also relates to the method for manufacturing the printed matter according to 1) or 2) above, wherein the content of the photoinitiator in the active energy ray-curable composition is 14% by mass or less in the total amount of the composition in each composition.

[0017] The present invention also relates to the method for manufacturing the printed matter according to 1) or 2) above, wherein the active energy ray-curable composition contains urethane (meth) acrylate.

[0018] The present invention also relates to the method for manufacturing the printed matter as described above, wherein the urethane (meth) acrylate contains urethane (meth) acrylate having 3 or more (meth) acryloyl groups.

[0019] The present invention also relates to the method for manufacturing the printed matter as described above, wherein the printed matter is a packaging container. The present invention also relates to the method for manufacturing the printed matter as described above, wherein the printed matter is a book.

Advantages of the Invention

[0020] According to the present invention, when using two or more active energy ray-curable compositions, even if the number of light sources that generate active energy rays is two or less, it has excellent curability and enables the stable production of high-quality printed matter over a long period of time. A method for manufacturing a printed matter has become possible.

Brief Description of the Drawings

[0021]

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Figure 7B

Best Mode for Carrying Out the Invention

[0022] Hereinafter, embodiments of the present invention will be described in detail. However, the present invention is not limited to the embodiments described below, and various modifications are possible without departing from the gist of the present invention.

[0023] The present invention is a method for manufacturing a printed matter in which two or more active energy ray-curable compositions, which were difficult in the prior art, are each printed using a transfer roll 8 (see FIG. 2), and after printing all the compositions, they are cured with two or fewer light sources. By using two or fewer light sources, power consumption can be reduced compared to the prior art, and reduction of energy consumption and carbon dioxide emissions can be achieved by the present invention without impairing printability. Furthermore, heat generated by using two or fewer light sources can also be suppressed.

[0024] The terms used in this specification will be explained. “(Meth)acrylate” means acrylate and / or methacrylate. “Active energy ray” means an energy ray having the property of causing a chemical change such as a chemical reaction in the irradiated material by irradiating ultraviolet rays. Also, “PO” represents “propylene oxide” and “EO” represents “ethylene oxide”.

[0025] <Active energy ray-curable composition> The active energy ray-curable composition in the present invention is a composition that cures by irradiating active energy rays and forms a cured film. The active energy ray-curable composition in the present invention contains a photopolymerization initiator and a (meth)acrylate compound.

[0026] <(Meth)acrylate compound> The active energy ray-curable composition in the present invention contains a (meth)acrylate compound.

[0027] As the (meth)acrylate compound, specifically, 2-ethylhexyl (meth)acrylate, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, β-carboxyethyl (meth)acrylate, 4-tert-butylcyclohexanol (meth)acrylate, tetrahydrofurfuryl acrylate, alkoxylated tetrahydrofurfuryl acrylate, caprolactone (meth)acrylate, lauryl (meth)acrylate, stearyl (meth)acrylate, isoamyl (meth)acrylate, 2-phenoxyethyl (meth)acrylate, isodecyl (meth)acrylate, 3,3,5-trimethylcyclohexanol (meth)acrylate, cyclohexyl (meth)acrylate, isobornyl (meth)acrylate, norbornyl (meth)acrylate, dicyclopentanyl (meth)acrylate, dicyclopentenyl(oxyethyl)(meth)acrylate, 1,4-cyclohexanedimethanol (meth)acrylate, cyclic trimethylolpropane formal (meth)acrylate, benzyl (meth)acrylate, EO-modified (2) nonylphenol acrylate, (2-methyl-2-ethyl-1,3-dioxolan-4-yl)methyl acrylate, acryloylmorpholine and other monofunctional (meth)acrylate compounds having one (meth)acryloyl group, 1,3-butylene glycol di(meth)acrylate, 1,4-butanediol di(meth)acrylate, 3-methyl-1,5-pentanediol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, 1,9-nonanediol di(meth)acrylate, 1,10-decanediol di(meth)acrylate, 1,2-dodecanediol di(meth)acrylate, neopentyl glycol di(meth)acrylate, polyethylene glycol (200) di(meth)acrylate, polyethylene glycol (300) di(meth)acrylate, polyethylene glycol (400) di(meth)acrylate, polyethylene glycol (600) di(meth)acrylate, hydroxypivalic acid neopentyl glycol di(meth)acrylate, dipropylene glycol di(meth)acryl Rate, tripropylene glycol di(meth)acrylate, EO-modified (2) 1,6-hexanediol di(meth)acrylate, PO-modified (2) neopentyl glycol di(meth)acrylate, (neopentyl glycol-modified) trimethylolpropane di(meth)acrylate, dimethyloltricyclodecane di(meth)acrylate, EO-modified (4) bisphenol A di(meth)acrylate, PO-modified (4) bisphenol A di(meth)acrylate, cyclohexanedimethanol di(meth)acrylate, dimethylol-tricyclodecane di(meth)acrylate, dicyclopentanyl di(meth)acrylate, tris(2-hydroxyethyl) isocyanurate di(meth)acrylate and other difunctional (meth)acrylate compounds having two (meth)acryloyl groups, Trimethylolpropane tri(meth)acrylate, EO-modified (3) trimethylolpropane tri(meth)acrylate, PO-modified (3) trimethylolpropane tri(meth)acrylate, ε-caprolactone-modified tris-(2-acryloxyethyl) isocyanurate, ethoxylated isocyanuric acid tri(meth)acrylate, tris(2-hydroxyethyl) isocyanurate tri(meth)acrylate, pentaerythritol tri(meth)acrylate and other trifunctional (meth)acrylate compounds having three (meth)acryloyl groups, Pentaerythritol tetra(meth)acrylate, ditrimethylolpropane tetra(meth)acrylate and other tetrafunctional (meth)acrylate compounds having four (meth)acryloyl groups, dipentaerythritol penta(meth)acrylate and other pentafunctional (meth)acrylate compounds having five (meth)acryloyl groups, Dipentaerythritol hexa(meth)acrylate and other hexafunctional (meth)acrylate compounds having six (meth)acryloyl groups, and the like can be mentioned.

[0028] Also, as the (meth)acrylate compound, urethane (meth)acrylate, polyester (meth)acrylate, epoxy (meth)acrylate, etc. can also be used.

[0029] Urethane (meth)acrylate can be obtained, for example, by reacting a diisocyanate with (meth)acrylates having a hydroxyl group, or by reacting an isocyanate group-containing urethane prepolymer obtained by reacting a polyol and a polyisocyanate under conditions of an excess of isocyanate groups with (meth)acrylates having a hydroxyl group. Alternatively, it can also be obtained by reacting a hydroxyl group-containing urethane prepolymer obtained by reacting a polyol and a polyisocyanate under conditions of an excess of hydroxyl groups with (meth)acrylates having an isocyanate group.

[0030] Polyester (meth)acrylate can be obtained, for example, by reacting a polyester polycarboxylic acid obtained by polycondensing a polybasic acid and a polyhydric alcohol with a hydroxyl group-containing (meth)acrylate or the like.

[0031] Epoxy (meth)acrylate includes, for example, those obtained by esterifying the glycidyl group of an epoxy resin with (meth)acrylic acid to convert the functional group into a (meth)acrylate group, such as (meth)acrylic acid adducts to bisphenol A type epoxy resins and (meth)acrylic acid adducts to novolak type epoxy resins.

[0032] Among the above (meth)acrylate compounds, it is preferable to contain urethane (meth)acrylate. By using urethane (meth)acrylate, a good balance between curability and printability can be achieved. As a compound containing urethane (meth)acrylate, for example, those described in Japanese Patent No. 7428842 or Japanese Patent Application No. 2023-066275 are suitable.

[0033] In the present invention, the above (meth)acrylate compound may be used alone or in combination of two or more.

[0034] From the viewpoint of curability, the active energy ray-curable composition in the present invention preferably contains a (meth)acrylate compound having three or more (meth)acryloyl groups, and more preferably contains a urethane (meth)acrylate having three or more (meth)acryloyl groups. The content of the (meth)acrylate compound having three or more (meth)acryloyl groups is preferably 10% by mass or more based on the total amount of the composition.

[0035] In the present invention, the iodine value IV of the active energy ray-curable composition is 100 or more from the viewpoint of curability. The iodine value IV is the number of grams of iodine that can be added to 100 g of the sample. The larger this value, the larger the number of double bonds in the sample. From the viewpoints of curability and stability, it is more preferably 110 or more and 220 or less, and even more preferably 120 or more and 170 or less in iodine value IV. When the iodine value IV is within this range, the curability and stability of the active energy ray-curable composition are good. The measurement of the iodine value IV is carried out in accordance with JIS K 0070-1992.

[0036] <Photoinitiator> In the present invention, the active energy ray-curable composition preferably contains a photoinitiator particularly when ultraviolet rays are used as the active energy ray source. The photoinitiator in the present invention is a compound that undergoes a chemical change and generates radicals through the action of light or interaction with the electronically excited state of a sensitizing dye. Among them, a photo radical polymerization initiator is preferably used from the viewpoint that polymerization can be initiated by means of exposure.

[0037] There is no particular limitation on the photoinitiator in the present invention, and known photoinitiators can be used. Specific examples include benzophenone-based compounds, dialkoxyacetophenone-based compounds, α-hydroxyalkylphenone-based compounds, α-aminoalkylphenone-based compounds, acylphosphine oxide-based compounds, thioxanthone-based compounds, and the like. Also, the photoinitiator may be used alone or in combination of two or more. To obtain excellent curability, it is more preferably two or more.

[0038] Examples of the benzophenone-based compound include benzophenone, methylbenzophenone, methyl o-benzoylbenzoate, 4-phenylbenzophenone, 4,4'-bis(diethylamino)benzophenone, (1-[4-(4-benzoylphenylsulfanyl)phenyl]-2-methyl-2-(4-methylphenylsulfonyl)propan-1-one, 4-(4-methylphenylthio)benzophenone, methyl o-benzoylbenzoate, 4,4'-dichlorobenzophenone, hydroxybenzophenone, 4-benzoyl-4'-methyl-diphenyl sulfide, acrylated benzophenone, 3,3',4,4'-tetra(t-butylperoxycarbonyl)benzophenone, 3,3'-dimethyl-4-methoxybenzophenone, thioxanthone-based compounds such as 2-isopropylthioxanthone, 2,4-dimethylthioxanthone, 2,4-diethylthioxanthone, 2,4-dichlorothioxanthone, Michler's ketone, 4,4'-bis(diethylamino)benzophenone, 3,3',4,4'-tetra(t-butylperoxycarbonyl)benzophenone, benzophenone derivative polymers, and the like.

[0039] Examples of the dialkoxyacetophenone-based compound include 2,2-dimethoxy-2-phenylacetophenone, dimethoxyacetophenone, diethoxyacetophenone, and the like.

[0040] Examples of the α-hydroxyalkylphenone-based compound include 1-hydroxy-cyclohexylphenylketone, 2-hydroxy-2-methyl-1-phenyl-propan-1-one, 1-[4-(2-hydroxymethoxy)-phenyl]-2-hydroxy-2-methyl-1-propan-1-one, 2-hydroxy-1-{4-[4-(2-hydroxy-2-methyl-propionyl)-benzyl]phenyl}-2-methyl-propan-1-one, and the like.

[0041] Examples of the above α-aminoalkylphenone compounds include 2-methyl-1-[4-(methoxythio)phenyl]-2-morpholinopropan-1-one, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)butanone-1, 2-(dimethylamino)-2-[(4-methylphenyl)methyl]-1-[4-(4-morpholinyl)phenyl]-1-butanone, ethoxyphenyl(2,4,6-trimethylbenzoyl)phosphine oxide, and the like.

[0042] Examples of the above acylphosphine oxide compounds include diphenylacylphenylphosphine oxide, 2,4,6-trimethylbenzoyl-diphenylphosphine oxide, bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide, ethoxyphenyl(2,4,6-trimethylbenzoyl)phosphine oxide, and the like.

[0043] Examples of the above thioxanthone compounds include 2-isopropylthioxanthone, 2,4-dimethylthioxanthone, 2,4-diethylthioxanthone, 2,4-dichlorothioxanthone, 1-chloro-4-propylthioxanthone, 2-chlorothioxanthone, 2-isopropylthioxanthone, isopropylthioxanthone dimer, and the like.

[0044] From the viewpoint of curability, a combination of a thioxanthone compound and other initiator compounds is preferable as the above photoinitiator. More preferably, it is a combined use of a thioxanthone compound and an α-aminoalkylphenone compound and / or an acylphosphine oxide compound.

[0045] From the viewpoints of curability and printing suitability, the content of the photoinitiator in the active energy ray-curable composition is preferably 14% by mass or less, more preferably 3 to 14% by mass, still more preferably 4 to 12% by mass, and particularly preferably 4 to 10% by mass. When it is 14% by mass or less, the halftone reproducibility during printing becomes good.

[0046] When the active energy ray-curable composition in the present invention is cured by irradiating with ultraviolet rays, it is only necessary to add a photoinitiator to the composition. However, in order to further improve the curability, a photosensitizer can also be used in combination. Examples of the photosensitizer include amines such as triethanolamine, methyldiethanolamine, dimethylethanolamine, triisopropanolamine, methyl 4-dimethylaminobenzoate, ethyl 4-dimethylaminobenzoate, isoamyl 4-dimethylaminobenzoate, (2-dimethylamino)ethyl benzoate, (n-butoxy)ethyl 4-dimethylaminobenzoate, and 2-ethylhexyl 4-dimethylaminobenzoate.

[0047] <Resin> The active energy ray-curable composition in the present invention can use a resin. The resin is preferably one having excellent compatibility with the (meth)acrylate compound. Specifically, diallyl phthalate resin, rosin-modified resin, polyvinyl chloride, poly(meth)acrylate ester, epoxy resin, polyester resin, polyurethane resin, cellulose derivative (for example, ethyl cellulose, cellulose acetate, nitrocellulose), vinyl chloride-vinyl acetate copolymer, polyamide resin, polyvinyl acetal resin, alkyd resin, petroleum resin, urea resin, synthetic rubber such as butadiene-acrylonitrile copolymer, and the like can be mentioned.

[0048] From the viewpoint of the fluidity of the active energy ray-curable composition, the resin in the present invention is preferably contained in an amount of 3 to 40% by mass based on the total amount of the composition. From the same viewpoint of fluidity, it is preferable to use diallyl phthalate resin, rosin-modified resin, epoxy resin, polyester resin, polyurethane resin, alkyd resin, or petroleum resin as the resin in the present invention.

[0049] <Colorant> In the active energy ray-curable composition of the present invention, a colorant can be used. By containing a colorant, a colored ink can be obtained, and by not using a colorant, a clear ink (hereinafter also referred to as "varnish") can be obtained. As the colorant, at least one of a pigment and a dye can be used, but from the viewpoint of light resistance, it is preferable to use a pigment.

[0050] There is no particular limitation on the pigment in the present invention, and known pigments can be used. Either an inorganic pigment or an organic pigment can be used as the pigment.

[0051] Examples of the inorganic pigment include carbon blacks such as furnace black, lamp black, acetylene black, and channel black, iron oxide, titanium oxide, and the like.

[0052] Examples of the organic pigment include soluble azo pigments such as β-naphthol-based, β-oxynaphthoic acid-based, β-oxynaphthoic acid anilide-based, acetoacetic acid anilide-based, and pyrazolone-based; insoluble azo pigments such as β-naphthol-based, β-oxynaphthoic acid anilide-based, acetoacetic acid anilide-based monoazo, acetoacetic acid anilide-based disazo, and pyrazolone-based; phthalocyanine-based pigments such as copper phthalocyanine blue, halogenated (for example, chlorinated or brominated) copper phthalocyanine blue, sulfonated copper phthalocyanine blue, and metal-free phthalocyanine; quinacridone-based, dioxazine-based, threne-based (such as pyranthrone, anthraanthrone, indanthrone, anthrapyrimidine, flavanthrone, thioindigo-based, anthraquinone-based, perinone-based, perylene-based, etc.), isoindolinone-based, metal complex-based, quinophthalone-based, diketopyrrolo Examples thereof include polycyclic pigments and heterocyclic pigments such as roll-based.

[0053] More specifically, as shown by the C.I. Color Index, examples of the black pigment include C.I. Pigment Black 1, 6, 7, 9, 10, 11, 28, 26, 31, and the like.

[0054] Examples of white pigments include C.I.Pigment White 5, 6, 7, 12, 28, etc.

[0055] Examples of yellow pigments include C.I.Pigment Yellow 1, 2, 3, 12, 13, 14, 16, 17, 18, 24, 73, 74, 75, 83, 93, 95, 97, 98, 100, 108, 109, 110, 114, 120, 128, 129, 138, 139, 174, 150, 151, 154, 155, 167, 180, 185, 213, etc.

[0056] Examples of blue or cyan pigments include C.I.Pigment Blue 1, 2, 14, 15, 15:1, 15:2, 15:3, 15:4, 60, 62, etc.

[0057] 214, 242, 254, 255, 264, 266, 269, C.I.Pi gment Violet 19, etc.

[0058] Examples of green pigments include C.I.Pigment Green 1, 2, 3, 4, 7, 8, 10, 15, 17, 26, 36, 45, 50, etc.

[0059] Examples of purple pigments include C.I.Pigment Violet 1, 2, 3, 4, 5:1, 12, 13, 15, 16, 17, 19, 23, 25, 29, 31, 32, 36, 37, 39, 42, etc. Examples of orange pigments include C.I.Pigment Orange 13, 16, 20, 34, 36, 38, 39, 43, 51, 61, 63, 64, 74, etc.

[0060] In the present invention, the above pigments may be used alone or in combination of two or more.

[0061] In the present invention, the colorant can be used in any content as long as the target concentration can be reproduced. When using the colorant, it is preferably 5 to 60% by mass based on the total mass of the composition.

[0062] <Extender pigment> The composition of the present invention can contain an extender pigment. As the extender pigment in the present invention, it is preferable to use inorganic fine particles.

[0063] Specific examples of the extender pigment include powdered calcium carbonate, precipitated calcium carbonate, precipitated barium sulfate, gypsum, clay (China Clay), silica, diatomaceous earth, talc, kaolin, alumina white, barium sulfate, aluminum stearate, calcium stearate, calcium carbonate, magnesium carbonate, barite powder, abrasive powder, silicone, glass beads, and the like. These inorganic fine particles can add effects such as adjusting the fluidity of the composition, preventing misting, and preventing penetration into printing substrates such as paper.

[0064] The extender pigment in the present invention can be used in any content to add the intended effects such as adjusting fluidity, preventing misting, and preventing penetration into printing substrates such as paper, and is preferably 0.1 to 10% by mass based on the total mass of the composition.

[0065] <Photopolymerization inhibitor> The composition of the present invention can contain a photopolymerization inhibitor. By containing a photopolymerization inhibitor, excellent storage stability can be exhibited.

[0066] As the photopolymerization inhibitor in the present invention, from the viewpoint of storage stability, it preferably contains one or more selected from the group consisting of nitroso compounds, phenolic compounds, quinone compounds, and piperidine compounds.

[0067] Examples of the nitroso compound include nitrobenzene, aluminum N-nitrosophenylhydroxylamine, tri-p-nitrophenylmethyl, picric acid, cupferron, butyraldoxime, methyl ethyl ketoxime, cyclohexanone oxime, and the like.

[0068] Examples of the phenolic compound include (alkyl)phenol, p-methoxyphenol, o-isopropylphenol, catechol, resorcinol, t-butylcatechol, pyrogallol, dibutylcresol, guaiacol, and the like.

[0069] Examples of the quinone compound include hydroquinone, t-butylhydroquinone, p-benzoquinone, 2,5-di-tert-butyl-p-benzoquinone, and the like.

[0070] Examples of the piperidine compound include phenothiazine and the like.

[0071] In addition, as the photopolymerization inhibitor in the present invention, it is also possible to use a photopolymerization inhibitor other than the above-described nitroso compound, phenolic compound, quinone compound, and piperidine compound (also referred to as "other photopolymerization inhibitor"). Specific examples of the other photopolymerization inhibitor include 1,1-picrylhydrazyl, dithiobenzoyl disulfide, N-(3-oxyanilino-1,3-dimethylbutylidene)aniline oxide, cyclohexanone oxime cresol, and the like.

[0072] The content of the photopolymerization inhibitor is preferably 0.05 to 5.0% by mass, more preferably 0.1 to 1.0% by mass, based on the total mass of the composition.

[0073] <Additive> The composition of the present invention may further contain various additives such as an antifriction agent, an antiblocking agent, a lubricant, etc. as additives according to the purpose. The various additives can be added to the composition by a conventional method. When adding various additives to the composition of the present invention, it is preferable to adjust the blending amount within a range that does not inhibit the effects of other materials. The blending amount of various additives is preferably 20% by mass or less in the total amount of the composition.

[0074] <Method for manufacturing printed matter> The printed matter in the present invention includes a step of printing two or more kinds of the active energy ray-curable compositions in the present invention on a substrate using a transfer roll respectively, and a step of curing the active energy ray-curable compositions using two or less active energy ray sources after printing all the compositions. The substrate is not particularly limited, and known ones can be used. Specifically, coated papers such as art paper, coated paper, and cast paper, uncoated papers such as high-quality paper, medium-quality paper, and newsprint, synthetic papers such as Yupo paper, and plastic films such as PET (polyethylene terephthalate), PP (polypropylene), and OPP (biaxially stretched polypropylene) can be mentioned. Also, the substrate may have a printing layer. In that case, it may be printed with the active energy ray-curable composition in the present invention on the printing layer.

[0075] As a method for printing the active energy ray-curable composition in the present invention on a substrate, there is no particular limitation as long as it is a printing method using a transfer roll 8 for supplying the active energy ray-curable composition, but printing methods such as offset printing (ordinary lithography using dampening water and waterless lithography not using dampening water), flexographic printing, gravure printing, and screen printing are preferable. More preferably, it is offset printing.

[0076] In this specification, the light source that generates active energy rays typically includes light sources that generate ionizing radiation such as ultraviolet rays, electron beams, X-rays, α-rays, β-rays, and γ-rays, and light sources that generate microwaves, high frequencies, etc. However, as long as it can generate radical active species, any energy species may be used, and light sources that generate visible light, infrared rays, and laser beams may also be used. Among these active energy ray sources, in order to cure the active energy ray curable composition in the present invention, it is preferable to use a light source that generates ultraviolet rays. Preferred light sources that generate ultraviolet rays include LEDs, ultra-high pressure mercury lamps, high pressure mercury lamps, medium pressure mercury lamps, low pressure mercury lamps, metal halide lamps, xenon lamps, carbon arc lamps, helium-cadmium lasers, YAG lasers, excimer lasers, and argon lasers.

[0077] The intensity of the light source that generates ultraviolet rays is represented by the power density (W / cm 2 ) in the case of an LED. From the viewpoints of curability and energy consumption, it is preferable to use an LED light source of 5 W / cm 2 or more and 30 W / cm 2 or less. By setting it to 5 W / cm 2 or more, troubles due to curability can be prevented, and by setting it to 30 W / cm 2 or less, the light source introduction cost and running cost can be suppressed, and it is excellent in economy. For those other than LEDs, the light source output is represented by W / cm obtained by dividing the total input watt (W) by the emission length (cm). From the viewpoints of curability and energy consumption, it is preferable to use a light source of 80 W / cm or more and 400 W / cm or less. By setting it to 80 W / cm or more, troubles due to curability can be prevented, and by setting it to 400 W / cm or less, the light source introduction cost and running cost can be suppressed, and it is excellent in economy.

[0078] In the production speed of the printed matter in the present invention, in the case of sheet-fed printing, regardless of the type of the substrate, it is preferably 20,000 sheets / hour or less from the viewpoint of curability. In the case of continuous printing in a roll-fed type such as a rotary printing machine, regardless of the type of the substrate, it is preferably 550 m / min or less from the viewpoint of curability.

[0079] In the method for manufacturing a printed matter of the present invention, from the viewpoint of printability, the surface temperature of the transfer roll 8 during printing is preferably 16 to 40°C, more preferably 20 to 40°C. When the surface temperature of the transfer roll 8 during printing is 16 to 40°C, the transferability of the ink, the halftone reproducibility, the curability, and the dot gain are good, and a clear printed matter can be provided.

[0080] The printed matter manufactured according to the present invention is applicable to various substrates, various printed matters for books, various printed matters for packaging such as paper, various plastic printed matters, printed matters for seals / labels, art printed matters, metal printed matters (art printed matters, printed matters for beverage cans, food printed matters such as canned foods), printed matters such as packaging containers.

[0081] Examples of the packaging container include a pack for filling beverages, containers for confectionery and food, pouches and lidded containers, cups and trays. These packaging containers contain at least a part of the printed matter printed according to the present invention.

[0082] A book is a bundle of papers printed according to the present invention, bound together, and provided with a cover, and examples include those in which information and patterns such as comics, art, history, study reference books, specialized books, science, and photo albums are described by printing.

Example

[0083] Hereinafter, the present invention will be described more specifically with reference to examples, but the present invention is not limited to these examples. In addition, "parts" described in this specification represent parts by mass, and "%" represents mass%.

[0084] (Varnish Production Example 1) Into a four-necked flask equipped with a stirrer, a Dean-Stark tube, a thermometer, and a gas introduction tube, 30 parts of Daiso Dap A (weight average molecular weight 30,000, manufactured by Osaka Soda Co., Ltd.) and 70 parts of MIRAMER M410 (trimethylolpropane tetraacrylate, manufactured by Misumi Specialty Chemicals Co., Ltd.) were placed, and the mixture was heated to 100°C while stirring and stirred and melted at 100°C for 2 hours to obtain a Daiso Dap A varnish with an iodine value IV of 169.

[0085] (Varnish Production Example 2) A varnish with an iodine value of IV 177 was obtained in the same procedure as in Varnish Production Example 1, except that Daiwa Isodap was used (manufactured by Osaka Soda Co., Ltd.) instead of Daiwa Dap A.

[0086] (Varnish Production Example 3) A RADOPAR AD-032 varnish with an iodine value of IV 173 was obtained in the same procedure as in Varnish Production Example 1, except that RADOPAR AD-032 (manufactured by Osaka Soda Co., Ltd.) was used instead of Daiwa Dap A.

[0087] (Varnish Production Example 4) A rosin-modified resin varnish with an iodine value of IV 152 was obtained in the same procedure as in Varnish Production Example 1, except that a rosin-modified resin (Resin 4 described in paragraph number 0076 of International Publication No. 2017 / 164246) was used instead of Daiwa Dap A.

[0088] (Production of Active Energy Ray-Curable Composition) According to the composition in Table 1, the raw materials were mixed and kneaded with a three-roll mill to obtain active energy ray-curable compositions 1 to 29.

[0089] The details of the materials described in Table 1 are described below. <(Meth)acrylate Compound> ·MIRAMER M600: Dipentaerythritol hexaacrylate, manufactured by Miwon Specialty Chemical Co., Ltd., iodine value IV 264 ·MIRAMER M410: Ditrimethylolpropane tetraacrylate, manufactured by Miwon Specialty Chemical Co., Ltd., iodine value IV 218 ·EBECRYL 1291: Urethane acrylate, manufactured by Daicel Allnex Co., Ltd., iodine value IV 152, 6 acryloyl groups in the molecule ·ETERMER 2381: Trimethylolpropane PO-modified (3) triacrylate, manufactured by Changxing Materials Industry Co., Ltd., iodine value IV 162 · EBECRYL 4101: Urethane acrylate, manufactured by Daicel Ornex Co., Ltd., iodine value IV 69, with 3 acryloyl groups in the molecule · TPGDA: Tripropylene glycol diacrylate, manufactured by Daicel Ornex Co., Ltd., iodine value IV 169 · EBECRYL 225: Urethane acrylate, manufactured by Daicel Ornex Co., Ltd., iodine value IV 212, with 10 acryloyl groups in the molecule <Colorant> · Carbon black: Manufactured by Mitsubishi Chemical Corporation, Carbon Black MA11 · Yellow pigment: Manufactured by Clariant, Permanent Yellow BHS (C.I.Pigment Yellow 174) · Red pigment: Manufactured by Clariant, Permanent Rubine L5B-01 (C.I.Pigment Red 57:1) · Blue pigment: Manufactured by BASF, HELIOGEN BLUE D7088 (C.I.Pigment Blue 15:3) <Extender pigment> · Calcium carbonate: Manufactured by Shiraishi Kogyo Co., Ltd., Hakuenka O · Talc: Manufactured by Matsumura Sangyo Co., Ltd., High Filler 5000PJ · Silica: Manufactured by Tokuyama Corporation, Leorosil MT-10C <Photoinitiator> · Omnirad379EG: Manufactured by IGM RESINS, 2-dimethylamino-2-(4-methylbenzyl)-1-(4-morpholin-4-yl-phenyl)-butan-1-one · Omnirad819: Bis(2,4,6-trimethylbenzoyl)-phenyl-phosphine oxide manufactured by IGM RESINS · OmniradTPO-L: Ethoxyphenyl(2,4,6-trimethylbenzoyl)phosphine oxide manufactured by IGM RESINS · KAYACURE DETX-S: 2,4-Diethylthioxanthone manufactured by Nippon Kayaku Co., Ltd. <Photopolymerization inhibitor> ·TBHQ: Manufactured by Seiko Chemical Co., Ltd., phenolic compound, 2-t-butylhydroquinone

[0090]

Table 1

[0091]

Table 1

[0092]

Table 1

[0093] (Manufacture of printed matter) Examples 1 to 49, Comparative Examples 1 to 14 Printing was performed on the obtained active energy ray-curable composition under the following conditions. (Printing conditions) · Printing machine LITHRONE 26 (manufactured by Komori Corporation) · Substrate Paper: Manufactured by Oji Paper Co., Ltd., OK Top Coat + (79.1 g / m 2 ) Plastic: Manufactured by Idemitsu Unitech Co., Ltd., Super Pure Ray SG140 (PP) · Printing speed 15,000 sheets / hour · Light source (active energy ray source) Metal halide lamp (output 80 W / cm) manufactured by Eye Graphics Co., Ltd. Mercury lamp (output 80 W / cm) manufactured by Eye Graphics Co., Ltd. LED lamp (power density 7.5 W / cm 2 ) · Roller temperature Cooling water and warm water were passed through the roller to change the surface temperature of the roller · Printing density Yellow: 1.40, Red: 1.50, Blue: 1.60, Black: 1.75 · Substrate Examples 1 to 46 and Comparative Examples 1 to 10 used OK Top Coat + (79.1 g / m 2 ), manufactured by Oji Paper Co., Ltd., and Examples 47 to 49 and Comparative Examples 11 to 14 used Super Pure Ray SG140, manufactured by Idemitsu Unitech Co., Ltd.

[0094] <Method for Evaluating Humid Heat Blocking> The overlapping part of 100% of the halftone dots of the printed matter manufactured as described above was cut out into a 4 cm × 5 cm square, and the ink-printed surfaces were overlapped. Then, it was held at a temperature of 40°C, a humidity of 80%, and a load of 2 kg / cm 2 for 24 hours, and the state of the printed matter was evaluated according to the following criteria. A score of 3 or more indicates a level with no practical problems. (Evaluation Criteria) 5: No change in the printed surface 4: Peeling is observed in less than 10% of the printed area 3: Peeling is observed in 10% or more and less than 50% of the printed area 2: Peeling is observed in 50% or more and less than 70% of the printed area 1: Peeling is observed in 70% or more of the printed area

[0095] <Method for Evaluating Dot Gain> Using the printed matter manufactured as described above, the dot gain, i.e., how much the 50% halftone dots on the plate expanded during continuous printing of 5,000 sheets, was compared. A dot gain evaluation score of 2 or more indicates a level with no practical problems. A score of 3 or more is more preferable and can provide a clear printed matter. (Evaluation Criteria) 5: Dot gain is less than 17%, and a very clear printed matter that greatly exceeds the market requirement level can be provided 4: Dot gain is 17% or more and less than 19%, and a clear printed matter that sufficiently meets the market requirements can be provided 3: Dot gain is 19% or more and less than 22%, and a printed matter at a level acceptable to the market can be provided 2: Dot gain is 22% or more and less than 25%, which is the lower limit level acceptable to the market 1: Dot gain is 25% or more, and the market requirements are not met

[0096]

Table 2

[0097]

Table 2

[0098]

Table 2

[0099]

Table 2

[0100] For Examples 1 to 49 and Comparative Examples 1 to 14, the manufacturing conditions and evaluation results of the printed matter are shown in Table 2. The iodine value IV of the composition was described according to the name of the composition in the column.

[0101] As shown in Table 2, in Examples 1 to 49, both the damp heat blocking and dot gain were within the practical range. On the other hand, in Comparative Examples 1 to 10, one or more compositions with an iodine value IV of less than 100 were used, and the damp heat blocking did not reach the practical level. In Comparative Examples 11 to 14 where plastic was used for the base material and three light sources were used, the damp heat blocking did not reach the practical level.

[0102] As described above, the present invention is a method for manufacturing a printed matter including a step of printing two or more active energy ray-curable compositions on a base material using a transfer roll, and a step of curing the active energy ray-curable compositions printed using an active energy ray source after printing all the compositions. By setting the iodine value IV of the active energy ray-curable compositions to 100 or more in each composition, a printed matter with excellent curability and high quality maintained over a long period can be obtained even with a small number of active energy ray sources. The method for manufacturing this printed matter will be described in detail below.

[0103] (Method for manufacturing printed matter: Details of printing machine 91) A specific example of the method for manufacturing a printed matter according to the present invention will be described with reference to FIGS. 1 to 4D. FIG. 1 is a schematic configuration diagram of a printing machine 91, which is an offset printing machine used in one aspect of the method for manufacturing a printed matter according to the present invention. FIG. 2 is a schematic diagram showing a second printing roll group R2 of the printing machine 91. FIG. 3 is a schematic diagram showing the configuration of a second printing roll group R2A when the printing machine 91 is a flexographic printing machine. FIG. 4A is a cross-sectional view for explaining the structure of a multi-lamp type UV irradiation device 7 provided in the printing machine 91. FIG. 4B is a perspective view for explaining the mounting and dismounting operation of a lamp unit 7L in the UV irradiation device 7. FIG. 4C is a cross-sectional view showing a state where one lamp unit 7L is mounted on the UV irradiation device 7. FIG. 4D is a cross-sectional view showing a modified example of the UV irradiation device 7, which is a UV irradiation device 7A.

[0104] The printing machine 91 shown in FIG. 1 is an offset printing machine. The printing machine 91 includes a supply unit 10, a printing unit PT, a discharge unit 6, a conveyance unit TR, and a control device 9C. The control device 9C controls the overall operation of the printing machine 91.

[0105] A UV irradiation device 7 or a UV irradiation device 7A is arranged in the discharge unit 6. Hereinafter, an example in which the UV irradiation device 7 is arranged will be described first. The printing unit PT has first to fifth printing units 1 to 5, which are five printing units, and can perform printing on a printing object P with, for example, 2 to 5 types of inks or 4 or less types of inks and varnishes. In FIG. 1, the conveyance path of the printing object P is indicated by a thick line. The conveyance unit TR has a plurality of conveyance rollers for conveying the printing object P and a discharge conveyor 61, and conveys the printing object P along a conveyance path from the supply unit 10 through the printing unit PT to the discharge unit 6. The printing unit PT may have six or more printing units and be capable of performing printing by combining five or more colors of inks and varnishes.

[0106] The supply unit 10 supplies the printing object P to the printing unit PT. The printing object P supplied from the supply unit 10 is a substrate for printing, and a ruled line is printed with ink of a desired color in the printing unit PT. Varnish may be printed as needed. The ink and varnish used are UV-curable, for example, an active energy ray-curable composition shown in Table 2. The printing object P printed with ink of a desired color is conveyed in the direction of arrow DR by the discharge conveyor 61 of the discharge unit 6, and is irradiated with UV light by the UV irradiation device 7 during the conveyance. The irradiation operation of the UV irradiation device 7 is controlled by the irradiation control unit 9C4 (see FIG. 5) of the control device 9C. By this irradiation of UV light, the ink printed on the printing object P is cured to become a printed matter P6, and is placed on the discharge table 62 to form a bundle of printed matters P6t.

[0107] As shown in FIG. 5, the control device 9C includes a CPU 9C1 which is a central processing unit, a printing control unit 9C2, a conveyance control unit 9C3, an irradiation control unit 9C4, and a storage unit 9C5. Further, a display unit 9C6 for displaying information as an image is connected to the control device 9C. The printing control unit 9C2 controls the operations of the first to fifth printing roll groups R1 to R5 (described later) of the printing unit PT. The conveyance control unit 9C3 controls the operation of the conveyance unit TR. The irradiation control unit 9C4 controls the operation of the UV irradiation device 7. The storage unit 9C5 stores printing information Jp which is information regarding the next printing to be executed. The printing information Jp includes information on the specifications of the active energy ray-curable compositions which are a plurality of colors of ink and varnish used in the next printing. Further, this specification information includes the types of the active energy ray-curable compositions (ink and varnish) used for printing, their respective curing information, and iodine value VI. The display unit 9C6 displays the operation state of the printing machine 91, the printing content, instructions to the operator, and the like.

[0108] Based on the iodine value IV of each of the plurality of inks and varnishes used in the next printing, which are stored in the storage unit 9C5, the irradiation control unit 9C4 sets the number of lamp units 7L to be lit in the UV irradiation device 7, or the number of lamp units 7L to be mounted on the UV irradiation device 7. Details of this setting method will be described later.

[0109] Next, the configuration and operation of the printing machine 91 will be described in detail. The printing machine 91 is an offset printing machine, and the object to be printed P is, for example, a sheet. The supply unit 10 has a liftable supply table 101, and on the supply table 101, a stack of sheets P1, which is a stack of sheets to be printed by the printing unit PT, is placed. The supply unit 10 has a paper feeding device (not shown). The paper feeding device repeatedly supplies the topmost sheet of the stack of sheets P1 to the printing unit PT.

[0110] The first to fifth printing units 1 to 5 of the printing unit PT each have first to fifth printing roll groups R1 to R5. As a printing process, different colors of UV ink or varnish are printed in order on the object to be printed P supplied from the supply unit 10 using the object to be printed P as a substrate. The colors of the UV ink are, for example, in the order of black, indigo, red, and yellow from the supply unit 10 side (upstream side). Also, varnish is printed in the fifth printing unit. The UV ink and varnish to be printed are each the active energy ray-curable composition described above. The printing in the printing unit PT is not limited to the combination of ink and varnish, and ink alone may be used.

[0111] The first to fifth printing units 1 to 5 have first to fifth printing roll groups R1 to R5 with the same configuration. The schematic configuration of the second printing roll group R2 of the second printing unit 2 is shown in FIG. 2 as a representative.

[0112] As shown in FIG. 2, the second printing unit 2 is configured as a group of rollers in general offset printing. That is, the second printing unit 2 includes a water pan 21, a water roller 22, an ink pan 23, an ink roller 24, an ink calling roller 28, ink applying rollers 291, 292, a plate cylinder 25, a blanket cylinder 26, and a pressure cylinder 27. The rotation direction of each roller is indicated by an arrow. A printing plate with a ruled part made lipophilic and an unruled part made hydrophilic is wound around the plate cylinder 25. Water from the water pan 21 is transferred to the unruled part by the water roller 22, and ink K in the ink pan 23 is transferred to the ruled part by the ink roller 24, the ink calling roller 28, and the ink applying rollers 291, 292. In FIG. 2, for ease of understanding, the ink K is shown as ink (solid filling). The ink K adhering to the ruled part of the plate cylinder 25 is transferred to the blanket cylinder 26 and printed on a printing object P conveyed in the direction of arrow DR while being sandwiched between the blanket cylinder 26 and the pressure cylinder 27 that rotates in the direction of arrow DR1.

[0113] In offset printing as shown in FIG. 2, the ink applying rollers 291, 292, the plate cylinder 25, and the blanket cylinder 26 each serve as a transfer roller 8.

[0114] The printing machine 91 is not limited to an offset printing device and may be a flexographic printing device. In the case of a flexographic printing device, the group of rollers of the second printing unit 2 is replaced with the group of rollers of flexographic printing generally shown in FIG. 3. The same applies to the first and third to fifth printing units 1, 3 to 5.

[0115] FIG. 3 shows the configuration of a second printing roller group R2A using an anilox roller as an example of a group of rollers for flexographic printing. In FIG. 3, the second printing roller group R2A includes an ink pan 2A1, a fountain roller 2A2, an anilox roller 2A3, a plate cylinder 2A4, and a pressure cylinder 2A5. The rotation direction of each roller is indicated by an arrow in FIG. 3, and the ink K is shown as a thick black line.

[0116] The ink K in the ink pan 2A1 is picked up by the fountain roller 2A2 and transferred to the fine depressions formed on the surface of the anilox roller 2A3. The ink K transferred to the anilox roller 2A3 is then transferred to the convex portion of the printing plate wrapped around the plate cylinder 2A4, and the ink K transferred to the convex portion of the printing plate is sandwiched between the impression cylinder 2A5 and printed on the printing object P of the continuous base material unwound from the roll and conveyed in the direction of arrow DR.

[0117] In flexographic printing as shown in FIG. 3, the fountain roller 2A2, the anilox roller 2A3, and the plate cylinder 2A4 each responsible for supplying the ink from the ink pan 2A1 are transfer rollers 8.

[0118] Next, the UV irradiation device 7 will be described with reference to FIGS. 1 and 4A to 4C, and the UV irradiation device 7A will be described with reference to FIG. 4D. As shown in FIG. 1, the UV irradiation devices 7 and 7A irradiate the printing object P printed with uncured ink being conveyed in the discharge unit 6 with UV light as a curing process to cure the ink K.

[0119] First, the UV irradiation device 7 will be described. FIG. 4A is a cross-sectional view for explaining the structure of the multi-lamp type UV irradiation device 7 provided in the printing machine 91. The UV irradiation device 7 is an active energy ray irradiation device. FIG. 4B is a perspective view for explaining the mounting and dismounting operation of the lamp unit 7L in the UV irradiation device 7. FIG. 4C is a cross-sectional view showing a state where one lamp unit 7L is mounted on the UV irradiation device 7. In FIGS. 4A to 4C, the respective directions of up, down, left, right, front, and rear are defined by the arrows shown in the figure. The front-rear direction is defined with the conveyance direction of the printing object P as the front, and the left-right direction is defined as the left-right direction toward the front.

[0120] The UV irradiation device 7 has a housing 71. The housing 71 is in the shape of a vertically thin and flat box with an open left side. A door 712 for opening and closing the left side is attached to the housing 71. On the bottom plate 71b of the housing 71, a plurality of irradiation openings 71a that are long in the left - right direction are formed in parallel in the front - rear direction. In this example, four irradiation openings 71a are formed. On the bottom plate 71b, a pair of guides 711, 711 are arranged sandwiching each of the irradiation openings 71a in the front - rear direction. The guide 711 is a long member in the left - right direction with an L - shaped cross - section, and guides the insertion and removal of the straight - bar - shaped lamp unit 7L in the left - right direction. The irradiation part L is composed of the irradiation opening 71a and the pair of guides 711, 711 on both sides thereof. That is, the UV irradiation device 7 has first to fourth irradiation parts L1 to L4 as four irradiation parts L.

[0121] Fig. 4A shows a mode in which lamp units 7L (first to fourth lamp units 7L1 to 7L4) are mounted on all four irradiation parts L to make it a four - lamp mode, and Fig. 4C shows a mode in which a lamp unit 7L is mounted on the first irradiation part L1 which is one of the four irradiation parts L to make it a one - lamp mode.

[0122] The lamp unit 7L is formed in an elongated prismatic shape and is an active energy ray source that emits UV light LB, which is an active energy ray, from an emission surface 7La which is one side surface. The irradiation part L is provided with a locking mechanism (not shown) for locking the lamp unit 7L mounted with the emission surface 7La facing downward at a predetermined insertion position. A power supply and a cooling system (not shown) are connected to the lamp unit 7L locked at the predetermined insertion position, and the UV light LB is emitted under the control of the irradiation control unit 9C4. The emitted UV light LB passes through the irradiation opening 71a of the housing 71 and irradiates the printed object P moving forward below the irradiation opening 71a for a time corresponding to its moving speed. Thereby, the printed object P printed with uncured UV ink has the UV ink cured to become a printed matter P6.

[0123] The irradiation control unit 9C4 is capable of controlling UV irradiation based on the curing information stored in advance in the storage unit 9C5 of the control device 9C so that uncured UV ink, i.e., the uncured active energy ray-curable composition, cures. Controllable parameters are, for example, the irradiation output according to the number of mounted lamp units 7L and the conveyance speed of the discharge conveyor 61. The distance between the printing object P and the UV irradiation device 7 is maintained in an unchanged installation state.

[0124] Next, the UV irradiation device 7A will be mainly described with reference to FIG. 4D. FIG. 4D is a cross-sectional view showing the UV irradiation device 7A which is a modified example of the UV irradiation device 7. As shown in FIG. 4D, the UV irradiation device 7A has a plurality of irradiation units 7T capable of mounting one lamp unit 7L. That is, the UV irradiation device 7A has a plurality of irradiation portions L. In the example shown in FIG. 4D, the UV irradiation device 7A has five irradiation units 7T. That is, the UV irradiation device 7A has five irradiation portions L. An operator can attach and detach the lamp unit 7L for each irradiation unit 7T. Further, the irradiation control unit 9C4 of the control device 9C independently controls the lighting and extinguishing of each of the plurality of irradiation units 7T.

[0125] As shown in FIG. 4D, the UV light LB emitted from the emission surface 7La of the lamp unit 7L mounted on the irradiation unit 7T passes through the irradiation opening 71a and is irradiated to the printing object P moving forward below the irradiation opening 71a for a time corresponding to its moving speed. Thereby, the printing object P printed with uncured UV ink cures the UV ink to become the printed matter P6.

[0126] Here, both the irradiation output and the conveyance speed are difficult for an operator to intuitively grasp the absolute values visually, and it is necessary to check by visually observing the numerical values of the conveyance speed and the irradiation output displayed on the display unit 9C6. Further, even if an abnormality occurs in which the displayed value differs from the actual output value or the conveyance speed value due to a malfunction of the UV irradiation devices 7, 7A, etc., the abnormality cannot be grasped immediately.

[0127] Therefore, in one aspect of the method for manufacturing a printed matter according to the present invention, the UV irradiation device 7 and the UV irradiation device 7A are of a multi-lamp type in which the UV irradiation device 7 has n irradiation units L (n is an integer of 2 or more) and can mount a maximum of n lamp units 7L, and the UV irradiation device 7A is provided with n irradiation units 7T of a single-lamp type having one irradiation unit L and capable of mounting one lamp unit 7L. Then, the amount of energy irradiated from the UV irradiation devices 7 and 7A toward the uncured UV ink printed on the printing object P is adjusted by the number of lit or mounted lamp units 7L. That is, the number of lit lamps is the number of lit lamp units 7L among, for example, the n lamp units 7L mounted on the UV irradiation devices 7 and 7A. Also, the number of mounted lamps is the number of lit lamp units 7L mounted and lit on the UV irradiation devices 7 and 7A. At this time, as shown in Table 2, depending on whether the iodine value IV of the active energy ray-curable composition is equal to or greater than a predetermined value or less than the predetermined value, the number of lamp units 7L lit or mounted and lit in the UV irradiation device 7 is changed.

[0128] The determination procedure for the number of lit or mounted lamp units 7L based on this iodine value IV will be described with reference to FIGS. 6A to 7B. FIG. 6A is a flowchart showing a method for determining the number of lit lamp units 7L by the control device 9C. FIG. 6B is a flowchart showing a method for determining the number of mounted lamp units 7L by the control device 9C. FIG. 7A is a first table showing the relationship between the iodine value IV of the composition and the UV irradiation mode. FIG. 7B is a second table showing the relationship between the iodine value IV of the composition and the UV irradiation mode.

[0129] First, the method for determining the number of lit lamps in FIG. 6A will be described. As a preliminary setting, it is assumed that the UV irradiation device 7 or the UV irradiation device 7A can mount a maximum of n lamp units 7L (n is an integer of 2 or more). Then, as is clear from the comparison between Example 1 and Comparative Examples 11 to 14 in Table 2, in the printing of a combination of black ink 2 and yellow ink 3 both having an iodine value IV of 100 or more, the following settings are made in advance. That is, the preliminary setting condition J is set in advance so as to satisfy the following two modes. First, for a printed object P printed with a plurality of types of uncured UV inks all having an iodine value IV of 100 or more, when n lamp units 7L, which is the maximum number that can be mounted, are mounted on the UV irradiation devices 7 and 7A and UV light is irradiated with all lamps to cure the UV inks, the value of the damp heat blocking is 2 or less. Second, for a printed object P printed with a plurality of types of uncured UV inks all having an iodine value IV of 100 or more, when only (n - 1) or fewer lamp units 7L out of the n lamp units mounted on the UV irradiation device 7 are lit to irradiate UV light and cure the UV inks, the damp heat blocking value is 3 or more. Find the combination of the irradiation output of the UV light and the conveyance speed of the printed object P that satisfies these two modes, set it in advance as the preset condition J, and store it in the storage unit 9C5.

[0130] After setting the preset condition J in this way, for each combination of a plurality of inks (including varnishes), the minimum number of lit lamp units 7L at which various evaluations after curing are at a practical level or higher may be obtained and stored in the storage unit 9C5 as a table. For example, in the case of the combination of the black ink 2 and the yellow ink 5 in Example 5 of Table 2, when n = 3, the minimum number of lit lamps is one.

[0131] Then, when executing the next printing, as shown in Fig. 6A, the control device 9C refers to the preset condition J stored in the storage unit 9C5 and sets the irradiation output of the UV light and the conveyance speed to the preset condition J (S1). This preset condition J is maintained without principle change during printing.

[0132] The control device 9C refers to the printing information Jp stored in the storage unit 9C5 and determines whether the IV values of the plurality of inks used for the next printing are all 100 or more (S2). If the determination in (S2) is No (NO), the control device 9C sets the number of lamp units 7L lit by the UV irradiation devices 7 and 7A to the maximum number n in the UV irradiation devices 7 and 7A (S3), and externally instructs to light n lamp units 7L via the display unit 9C6 (S4).

[0133] When the determination in (S2) is yes (YES), the control device 9C sets the number of lamp units 7L lit by the UV irradiation devices 7 and 7A to less than n (S5). Further, when the above-described table is stored in the storage unit 9C5, the table is referred to, and the minimum number of lit lamps k [1 ≤ k ≤ (n - 1)] in the set of UV inks to be used is selected (S6), and it is displayed externally via the display unit 9C6 that k lamp units 7L are lit. The lighting and extinguishing operations of the UV irradiation devices 7 and 7A are controlled by the irradiation control unit 9C4.

[0134] When the lighting and extinguishing operations of the lamp unit 7L are manual operations by the operator, the operator lights the lamp units 7L with the number of lit lamps displayed on the display unit 9C6 for the UV irradiation device 7.

[0135] According to the above method, in printing corresponding to each example in Table 2, where the iodine value IV of all the inks and varnishes used is 100 or more, there is one or more lamp units 7L that are not lit in the UV irradiation devices 7 and 7A. Also, the content of the print information Jp remains unchanged during printing. Therefore, the operator can directly visually confirm whether there is a lamp unit 7L that is not lit and extinguished among the lamp units 7L attached to the irradiation unit L of the UV irradiation devices 7 and 7A during the printing operation. If there is an extinguished one, it can be directly visually grasped that printing is being performed using only the active energy ray-curable composition with an iodine value IV of 100 or more and that the irradiation intensity of the UV light LB is low enough, and that the irradiation intensity of the UV light is appropriate.

[0136] Next, the mounting number determination method in FIG. 6B will be described. As a prior setting, assume that the UV irradiation devices 7 and 7A are of the nb-lamp type that can mount a maximum of nb (nb is an integer of 2 or more) lamp units 7L. And as is clear from the comparison between Example 1 and Comparative Examples 11 to 14 in Table 2, in the printing of the combination of the black ink 2 and the yellow ink 3 both having an iodine value IV of 100 or more, the following settings are made in advance. That is, the prior setting condition J is set in advance so as to satisfy the following two modes. First, when irradiating the printed object P printed with a plurality of types of uncured UV inks all having an iodine value IV of 100 or more with UV light by mounting the maximum number nb of lamp units 7L on the UV irradiation devices 7, 7A to cure the UV inks, the value of damp heat blocking becomes 2 or less. Second, when irradiating the printed object P printed with a plurality of types of uncured UV inks all having an iodine value IV of 100 or more with UV light by mounting (nb - 1) or fewer lamp units 7L on the UV irradiation devices 7, 7A to cure the UV inks, the damp heat blocking value becomes 3 or more. Obtain a set of the irradiation output of the UV light and the conveyance speed of the printed object P that satisfies these two modes, set it in advance as the preset condition Jb, and store it in the storage unit 9C5.

[0137] After setting the preset condition Jb in this way, for each combination of a plurality of inks (including varnishes), the minimum number of mounted lamp units 7L at which various evaluations after curing are at a practical level or higher may be obtained and stored in the storage unit 9C5 as a table. For example, in the case of the combination of the black ink 2 and the yellow ink 5 in Example 5 of Table 2, when n = 3, the minimum number of mounted units is one.

[0138] Then, when executing the next printing, as shown in FIG. 6, the control device 9C refers to the preset condition Jb stored in the storage unit 9C5 and sets the irradiation output of the UV light and the conveyance speed to the preset condition Jb (S11). This preset condition Jb is maintained without being changed in principle during printing.

[0139] The control device 9C refers to the printing information Jp stored in the storage unit 9C5 and determines whether or not the IV values of the plurality of inks used for the next printing are all 100 or more (S12). When the determination in (S12) is No, the control device 9C sets the number of lamp units 7L to be mounted on the UV irradiation devices 7 and 7A as the maximum number n in the UV irradiation devices 7 and 7A (S13), and externally instructs via the display unit 9C6 to mount n lamp units 7L (S14). When the attachment / detachment of the lamp units 7L of the UV irradiation devices 7 and 7A is performed by an automatic attachment / detachment machine (not shown), the control device 9C instructs the automatic attachment / detachment machine to mount n lamp units 7L.

[0140] When the determination in (S12) is Yes, the control device 9C sets the number of lamp units 7L to be mounted on the UV irradiation devices 7 and 7A to be less than nb (S15). Further, when the above-described table is stored in the storage unit 9C5, the table is referred to, and the minimum number of mounted units kb [1 ≤ kb ≤ (nb - 1)] in the set of UV inks to be used is selected (S16), and externally instructed via the display unit 9C6 to mount kb lamp units 7L (S17). When the attachment / detachment of the lamp units 7L of the UV irradiation devices 7 and 7A is performed by an automatic attachment / detachment machine (not shown), the control device 9C instructs the automatic attachment / detachment machine to mount kb lamp units 7L.

[0141] When the attachment / detachment of the lamp unit 7L is performed manually by an operator, the operator mounts the number of lamp units 7L displayed on the display unit 9C6 on the UV irradiation devices 7 and 7A.

[0142] According to the above method, in printing corresponding to each example in Table 2, where the iodine value IV of all the inks and varnishes used is 100 or more, there is one or more empty irradiation portions L on the UV irradiation devices 7 and 7A on which the lamp units 7L are not mounted. Also, the content of the print information Jp is unchanged in the printing. Therefore, the operator can directly visually confirm whether there is an empty space on the irradiation portion L of the UV irradiation device 7 and 7A during the printing operation where the lamp unit 7L is not mounted, and if there is an empty space, that printing using only the active energy ray curable composition with an iodine value IV of 100 or more is being executed and that the irradiation intensity of the UV light LB is appropriate.

[0143] The table in FIG. 7A shows an example of the correspondence between the iodine value IV of each of the three types of active energy ray-curable compositions to be printed on the object to be printed P (Compositions 1 to 3) and the UV irradiation mode set by the control device 9C. In this case, the active energy ray-curable compositions are, for example, inks of different colors, and the iodine value IV of 100 or more is indicated by ○, and less than 100 is indicated by ▲. Also, there are two types of UV irradiation modes, A and B. When controlling the irradiation amount by the number of lit lamp units 7L, B is a mode in which the maximum number n (n is an integer of 2 or more) of lamp units 7L that can be mounted on the UV irradiation devices 7 and 7A are mounted and all are lit. And A is a mode in which n lamp units 7L are mounted and only 1 or more and (n - 1) or less of the lamp units 7L are lit. On the other hand, when controlling the irradiation amount by the number of mounted lamp units 7L, B is a mode in which the maximum number nb (nb is an integer of 2 or more) of lamp units 7L that can be mounted on the UV irradiation devices 7 and 7A are mounted and all are lit. And A is a mode in which 1 or more and (n - 1) or less of the lamp units 7L are mounted and lit. In the above, the characters n and nb are used separately for convenience in order to distinguish between the case of controlling the irradiation amount of the active energy rays by the number of lit lamps and the case of controlling by the number of mounted lamps. There is no other meaning than just the difference in the characters indicating the variables.

[0144] FIG. 7B shows the correspondence between the iodine value IV of each of the m types of active energy ray-curable compositions (Compositions 1 to m) to be printed on the object to be printed P and the UV irradiation mode. In this case, the active energy ray-curable compositions are, for example, inks of different colors, and when the iodine value IV is 100 or more for all of Compositions 1 to Composition m, it is indicated by ○, and when there is one or more less than 100, it is indicated by ▲. Also, A and B of the UV irradiation mode are the same as the content shown in FIG. 7A.

[0145] One aspect of the present invention is not limited to the above-described configuration and method, and may be modified without departing from the gist of the present invention.

[0146] The active energy ray is not limited to UV light. Also, generally, the UV irradiation device 7 often has a four-lamp type, that is, it is equipped with four irradiation parts L. Therefore, when n = 4 and the iodine value IV of the active energy ray curable composition which is ink and varnish is all 100 or more, the lamp units 7L which are the active energy ray sources may be lit or mounted and lit with only two or less. In this case, since more than half of the four irradiation parts L are turned off or vacant, the turned-off state or the vacant state can be grasped more surely and instantaneously by visual inspection.

Explanation of Signs

[0147] 10 Supply Unit 101 Supply Table 1 First Printing Unit 2 Second Printing Unit 2A1 Ink Pan 2A2 Fountain Roller 2A3 Anilox Roller 2A4 Plate Cylinder 2A5 Impression Cylinder 21 Water Pan 22 Water Roller 23 Ink Pan 24 Ink Roller 25 Plate Cylinder 26 Blanket Cylinder 27 Impression Cylinder 28 Ink Calling Roller 291,292 Ink Application Roller 3 Third Printing Unit 4 Fourth Printing Unit 5 Fifth Printing Unit 6 Discharge Unit 61 Discharge Conveyor 62 Discharge Table 7,7A UV Irradiation Device (Active Energy Ray Irradiation Device) 7L Lamp Unit (Active Energy Ray Source) 7La Emission Surface 7L1~7L4 First~Fourth Lamp Units 7T Irradiation Unit 71 Housing 71a Irradiation opening 711 Guide 712 Door 8 Transfer roller 91 Printing machine 9C Control device 9C1 CPU (Central processing unit) 9C2 Printing control unit 9C3 Conveying control unit 9C4 Irradiation control unit 9C5 Memory unit 9C6 Display unit IV Iodine value J, Jb Preset conditions Jp Printing information K Ink LB UV light (Active energy ray) L Irradiation unit L1 - L4 First - Fourth irradiation units P Object to be printed (Substrate) P6 Printed matter PT Printing section P1 Stack of single sheets P6t Bundle of printed matter R2 Second printing roll group R2A Second printing roll group (for flexographic printing) R3 Third printing roll group R4 Fourth printing roll group R5 Fifth printing roll group TR Conveying section

Claims

1. A printing step of printing two or more types of active energy ray-curable compositions onto a substrate using a transfer roll; a curing step of curing the active energy ray-curable composition printed on the substrate by irradiating the active energy ray from an active energy ray irradiation device after the printing step; A method for producing a printed matter, comprising: The two or more active energy ray-curable compositions each contain a (meth)acrylate compound, The active energy ray irradiation device is equipped with n active energy ray sources (n is an integer of 2 or more), When one of the two or more active energy ray-curable compositions has an iodine value of less than 100, n active energy ray sources are turned on to irradiate the active energy rays, When the iodine values ​​of the two or more active energy ray-curable compositions are all 100 or more, (n-1) or less active energy ray sources out of the n active energy ray sources are turned on to irradiate the active energy rays. A method for producing printed matter.

2. A printing step of printing two or more types of active energy ray-curable compositions onto a substrate using a transfer roll; a curing step of curing the active energy ray-curable composition printed on the substrate by irradiating the active energy ray from an active energy ray irradiation device after the printing step; A method for producing a printed matter, comprising: The two or more active energy ray-curable compositions each contain a (meth)acrylate compound, The active energy ray irradiation device is capable of mounting n active energy ray sources (n is an integer of 2 or more), When one of the two or more active energy ray-curable compositions has an iodine value of less than 100, n active energy ray sources are attached to the active energy ray irradiation device, and the active energy rays are irradiated, When the iodine values ​​of the two or more active energy ray-curable compositions are all 100 or more, the active energy ray irradiation device is equipped with (n-1) or less active energy ray sources and the active energy ray is irradiated. A method for producing printed matter.

3. The method for producing a printed matter according to claim 1 , wherein the amount of energy irradiated to the active energy ray-curable composition is adjusted by changing the number of the active energy ray sources that are turned on.

4. The method for producing a printed matter according to claim 2 , wherein the amount of energy irradiated to the active energy ray-curable composition is adjusted by adjusting the number of the active energy ray sources attached.

5. The method for producing a printed matter according to any one of claims 1 to 4, wherein the (n-1) or less is 2 or less.

6. 3. The method for producing a printed matter according to claim 1, wherein all of the two or more active energy ray-curable compositions have an iodine value of 110 or more and 220 or less.

7. 3. The method for producing a printed matter according to claim 1, wherein the surface temperature of the transfer roll during printing is 16 to 40°C.

8. The method for producing a printed matter according to claim 1 or 2, wherein the active energy ray-curable composition contains a photopolymerization initiator.

9. The method for producing a printed matter according to claim 1 or 2, wherein the content of the photopolymerization initiator in each active energy ray-curable composition is 14 mass % or less based on the total amount of the composition.

10. The method for producing a printed matter according to claim 1 or 2, wherein the active energy ray-curable composition contains a urethane (meth)acrylate.

11. The method for producing a printed matter according to claim 10, wherein the urethane (meth)acrylate contains a urethane (meth)acrylate having three or more (meth)acryloyl groups.

12. The method for producing a printed matter according to any one of claims 1 to 4, wherein the printed matter is a packaging container.

13. The method for producing a printed matter according to any one of claims 1 to 4, wherein the printed matter is a book.

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