Active energy ray-curable composition

Abstract

To provide: an active energy ray-curable composition with excellent fluidity which causes little dot shape collapse and can form sharp printed matter; and printed matter employing the same.SOLUTION: An active energy ray-curable composition contains a (meth)acrylate compound (A), and a carboxylic acid or carboxylic acid anhydride (B) having a molecular weight of 500 or less and not having a (meth)acryloyl group, where the content of the carboxylic acid or carboxylic acid anhydride (B) having a molecular weight of 500 or less and not having a (meth)acryloyl group is 3 mass% or less based on the total mass of the composition.SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to an active energy ray-curable composition for use in packaging and the like, and relates to an active energy ray-curable composition that makes it possible to provide clear printed matter. [Background technology]

[0002] Active energy beam-curable inks are solvent-free and instantly dry when exposed to active energy beams. As such, they are environmentally friendly, have excellent printability, and produce high-quality printed matter. As a result, they are widely used in a range of fields, from printing information such as magazines and flyers to packaging for food packaging such as paper containers.

[0003] In recent years, there has been an increasing demand for labor saving, labor saving, automation, and high speed in printing, and in particular, printing speeds are becoming increasingly faster. In addition, there is a demand for inks and varnishes that can stably produce high-quality printed matter over a long period of time without any trouble under various printing conditions, and various improvements to inks have been investigated.

[0004] Patent Document 1 discloses an active energy ray-curable ink containing a metal complex and a compound having a polar group, and although an evaluation is performed on the presence or absence of smearing during printing, it does not obtain clear printed matter, which meets market demand. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Patent Publication No. 2021-195503 Summary of the Invention [Problem to be solved by the invention]

[0006] The present invention provides an active energy ray-curable composition which produces clear prints with little distortion of dot shape and has excellent flowability, and a print using the same. [Means for solving the problem]

[0007] As a result of intensive research by the present inventors to solve the above problems, they found that the above problems can be solved by the active energy ray-curable composition shown below, and thus completed the present invention.

[0008] That is, the present invention provides an active energy ray-curable composition comprising a (meth)acrylate compound (A) and a carboxylic acid or carboxylic acid anhydride (B) having a molecular weight of 500 or less and no (meth)acryloyl group, The present invention relates to an active energy ray-curable composition, in which the content of the carboxylic acid or carboxylic acid anhydride (B) having a molecular weight of 500 or less and no (meth)acryloyl group is 3 mass % or less based on the total amount of the composition.

[0009] The present invention also relates to the above active energy ray-curable composition, wherein the carboxylic acid or carboxylic acid anhydride (B) having a molecular weight of 500 or less and no (meth)acryloyl group has a cyclic hydrocarbon structure in its structure.

[0010] The present invention also relates to the above-mentioned active energy ray-curable composition, wherein the carboxylic acid or carboxylic acid anhydride (B) having a molecular weight of 500 or less and no (meth)acryloyl group includes one or more selected from the group consisting of tert-butylbenzoic acid, benzoic acid, methylbenzoic acid, maleic anhydride, 1,2,3,6-tetrahydrophthalic anhydride, phthalic anhydride, 1,4-cyclohexanedicarboxylic acid, isophthalic acid, terephthalic acid, abietic acid, dehydroabietic acid, and trimellitic anhydride.

[0011] The present invention also relates to the above active energy ray-curable composition, which further contains a resin (C).

[0012] The present invention also relates to the above active energy ray-curable composition, which further contains a colorant (D).

[0013] The present invention also relates to the above active energy ray-curable composition, wherein the content of the resin (C) is 2 to 40 mass % based on the total amount of the composition.

[0014] Furthermore, the present invention relates to a laminate having a substrate and a layer formed by curing the above-mentioned active energy ray-curable composition with active energy rays. Effect of the Invention

[0015] According to the present invention, it is possible to provide an active energy ray-curable composition which exhibits little distortion of the halftone dot shape and has excellent fluidity, and a printed matter using the same. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0016] Hereinafter, the 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 spirit and scope of the present invention.

[0017] The terms used in this specification are explained below. "(Meth)acrylate" means acrylate and / or methacrylate. "Active energy rays" means energy rays that have the property of causing chemical changes such as chemical reactions in objects irradiated with ultraviolet light. "PO" stands for "propylene oxide" and "EO" stands for "ethylene oxide."

[0018] <(Meth)acrylate compound (A)> The active energy ray-curable composition of the present invention (hereinafter also referred to as "the composition") contains a (meth)acrylate compound (A). The (meth)acrylate compound (A) in the present invention is a compound having one or more (meth)acryloyl groups in the molecule. Specific examples of the (meth)acrylate compound (A) include 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-trimethylcyclo Monofunctional (meth)acrylate compounds having one (meth)acryloyl group, such as hexanol (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, and acryloylmorpholine; 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)acrylate (t) acrylate, 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, and bifunctional (meth)acrylate compounds having two (meth)acryloyl groups, such as tris(2-hydroxyethyl)isocyanurate di(meth)acrylate, trifunctional (meth)acrylate compounds having three (meth)acryloyl groups, such as 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, and pentaerythritol tri(meth)acrylate; tetrafunctional (meth)acrylate compounds having four (meth)acryloyl groups, such as pentaerythritol tetra(meth)acrylate and ditrimethylolpropane tetra(meth)acrylate; Pentafunctional (meth)acrylate compounds having five (meth)acryloyl groups, such as dipentaerythritol penta(meth)acrylate; and hexafunctional (meth)acrylate compounds having six (meth)acryloyl groups, such as dipentaerythritol hexa(meth)acrylate.

[0019] Furthermore, as the (meth)acrylate compound (A), urethane acrylate, polyester acrylate, epoxy acrylate, etc. can also be used.

[0020] Urethane acrylates include, for example, those obtained by reacting a diisocyanate with a (meth)acrylate having a hydroxyl group, and those obtained by reacting an isocyanate group-containing urethane prepolymer obtained by reacting a polyol with a polyisocyanate under conditions of an excess of isocyanate groups with a (meth)acrylate having a hydroxyl group, etc. Alternatively, they can also be obtained by reacting a hydroxyl group-containing urethane prepolymer obtained by reacting a polyol with a polyisocyanate under conditions of an excess of hydroxyl groups with a (meth)acrylate having an isocyanate group.

[0021] The polyester 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.

[0022] Examples of epoxy acrylates include 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 a (meth)acrylic acid adduct of a bisphenol A type epoxy resin and a (meth)acrylic acid adduct of a novolac type epoxy resin.

[0023] The (meth)acrylate compound (A) in the present invention may be used alone or in combination of two or more kinds.

[0024] As the (meth)acrylate compound (A) in the present invention, from the viewpoint of coating film strength after curing, it is preferable to use a (meth)acrylate compound having two or more (meth)acryloyl groups, and it is more preferable to use a (meth)acrylate compound having three or more (meth)acryloyl groups.

[0025] In the present invention, the content of the (meth)acrylate compound (A) is preferably from 20 to 95% by mass, and more preferably from 25 to 90% by mass, of the total amount of the composition from the viewpoint of curability.

[0026] <Carboxylic acid or carboxylic acid anhydride (B) having a molecular weight of 500 or less and no (meth)acryloyl group> The composition of the present invention contains 3% by mass or less of a carboxylic acid or carboxylic acid anhydride (B) having a molecular weight of 500 or less and no (meth)acryloyl group, based on the total amount of the composition.

[0027] Specific examples of the carboxylic acid or carboxylic acid anhydride (B) having a molecular weight of 500 or less and no (meth)acryloyl group in the present invention include: Examples of compounds having one carboxylic acid include aromatic monobasic acids such as benzoic acid, methylbenzoic acid, tert-butylbenzoic acid, naphthoic acid, and orthobenzoylbenzoic acid; resin acids such as abietic acid, neoabietic acid, parastric acid, dehydroabietic acid, pimaric acid, isopimaric acid, sandaracopimaric acid, and communic acid; and compounds such as stearic acid, palmitic acid, oleic acid, linoleic acid, abietic acid, neoabietic acid, parastric acid, dehydroabietic acid, pimaric acid, isopimaric acid, sandaracopimaric acid, and communic acid.

[0028] Examples of compounds having two or more carboxylic acids include 1,2,3,6-tetrahydrophthalic acid, 3-methyl-1,2,3,6-tetrahydrophthalic acid, 4-methyl-1,2,3,6-tetrahydrophthalic acid, 1,2-cyclohexanedicarboxylic acid, 1,3-cyclohexanedicarboxylic acid, 1,4-cyclohexanedicarboxylic acid, oxalic acid, malonic acid, succinic acid, glutaric acid, pimelic acid, sebacic acid, azelaic acid, alkenylsuccinic acids such as dodecenylsuccinic acid and pentadecenylsuccinic acid, o-phthalic acid, terephthalic acid, isophthalic acid, trimellitic acid, pyromellitic acid, maleic acid, fumaric acid, citraconic acid, itaconic acid, crotonic acid, isocrotonic acid, dihydroagatoic acid, and acid anhydrides thereof.

[0029] The carboxylic acid or carboxylic acid anhydride (B) having no (meth)acryloyl group and a molecular weight of 500 or less can be used alone or in combination of two or more kinds.

[0030] When the molecular weight is 500 or less, the fluidity of the composition is not impaired, and the clarity of the printed paper surface can be achieved.

[0031] Furthermore, from the viewpoint of the fluidity of the composition and the clarity of printing, it is preferable that the carboxylic acid or carboxylic acid anhydride (B) having a molecular weight of 500 or less and no (meth)acryloyl group is a carboxylic acid compound having a cyclic hydrocarbon structure in its structure. Among the carboxylic acid compounds having a cyclic hydrocarbon structure in their structure, compounds having one carboxylic acid include aromatic monobasic acids such as benzoic acid, methylbenzoic acid, tert-butylbenzoic acid, naphthoic acid, and orthobenzoylbenzoic acid, and resin acids such as abietic acid, neoabietic acid, palustric acid, dehydroabietic acid, pimaric acid, isopimaric acid, sandaracopimaric acid, and communic acid. Among the carboxylic acid compounds having a cyclic hydrocarbon structure in the structure, examples of compounds having two or more carboxylic acids include 1,2,3,6-tetrahydrophthalic acid, 3-methyl-1,2,3,6-tetrahydrophthalic acid, 4-methyl-1,2,3,6-tetrahydrophthalic acid, 1,2-cyclohexanedicarboxylic acid, 1,3-cyclohexanedicarboxylic acid, 1,4-cyclohexanedicarboxylic acid, o-phthalic acid, terephthalic acid, isophthalic acid, trimellitic acid, pyromellitic acid, maleic acid, fumaric acid, dihydroagatoic acid, and acid anhydrides thereof.

[0032] Furthermore, from the viewpoints of compatibility with (meth)acrylate compounds and printing clarity, the carboxylic acid or carboxylic acid anhydride (B) having a molecular weight of 500 or less and no (meth)acryloyl group preferably contains, as a carboxylic acid compound having a cyclic hydrocarbon structure in its structure, one or more selected from the group consisting of tert-butylbenzoic acid, benzoic acid, methylbenzoic acid, maleic anhydride, 1,2,3,6-tetrahydrophthalic anhydride, phthalic anhydride, 1,4-cyclohexanedicarboxylic acid, isophthalic acid, terephthalic acid, abietic acid, dehydroabietic acid, and trimellitic anhydride, and particularly preferably contains one or more selected from the group consisting of benzoic acid, maleic anhydride, 1,2,3,6-tetrahydrophthalic anhydride, phthalic anhydride, isophthalic acid, terephthalic acid, abietic acid, and dehydroabietic acid.

[0033] The content of the carboxylic acid or carboxylic anhydride (B) having no (meth)acryloyl group and having a molecular weight of 500 or less is 3% by mass or less based on the total amount of the composition. If it exceeds 3% by mass, the compatibility with the (meth)acrylate compound (A) deteriorates, and the flowability deteriorates. The content of the carboxylic acid or carboxylic anhydride (B) having no (meth)acryloyl group and a molecular weight of 500 or less is preferably 0.001% by mass to 2% by mass, and more preferably 0.003% by mass to 1% by mass. By setting it within this range, the flowability and the clarity of the printed matter are favorable.

[0034] <Resin (C)> The composition of the present invention preferably contains a resin (C), which provides suitable fluidity. The resin (C) in the present invention is preferably one having excellent compatibility with (meth)acrylate compounds, and examples thereof include diallyl phthalate resins, rosin-modified resins, polyvinyl chloride, poly(meth)acrylic acid esters, epoxy resins, polyester resins, polyurethane resins, cellulose derivatives (e.g., ethyl cellulose, cellulose acetate, nitrocellulose), vinyl chloride-vinyl acetate copolymers, polyamide resins, polyvinyl acetal resins, alkyd resins, petroleum resins, urea resins, and synthetic rubbers such as butadiene-acrylonitrile copolymers. Among these, from the viewpoint of fluidity, it is preferable to use one or more resins selected from the group consisting of diallyl phthalate resins, rosin-modified resins, epoxy resins, polyester resins, polyurethane resins, alkyd resins, and petroleum resins.

[0035] From the viewpoint of the flowability of the active energy ray-curable composition, the content of the resin (C) is preferably from 2 to 40 mass % relative to the total amount of the composition, and more preferably from 3 to 30 mass %.

[0036] The weight average molecular weight of the resin (C) is preferably from 1,000 to 50,000, and more preferably from 1,500 to 40,000, from the viewpoints of compatibility with the (meth)acrylate compound and flowability.

[0037] <Colorant (D)> A colorant (D) can also be used in the composition of the present invention. As the colorant (D), 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.

[0038] The pigment in the present invention is not particularly limited, and any known pigment can be used. Both inorganic and organic pigments can be used.

[0039] Examples of inorganic pigments include carbon blacks such as furnace black, lamp black, acetylene black, and channel black, iron oxide, and titanium oxide.

[0040] Examples of organic pigments include soluble azo pigments such as β-naphthol, β-oxynaphthoic acid, β-oxynaphthoic acid anilide, acetoacetate anilide, and pyrazolone; Examples of the pigments include insoluble azo pigments such as β-naphthol, β-oxynaphthoic acid anilide, acetoacetate anilide monoazo, acetoacetate anilide disazo, and pyrazolone pigments; phthalocyanine pigments such as copper phthalocyanine blue, halogenated (e.g., chlorinated or brominated) copper phthalocyanine blue, sulfonated copper phthalocyanine blue, and metal-free phthalocyanine; and polycyclic pigments and heterocyclic pigments such as quinacridone, dioxazine, threne (pyranthrone, anthranthrone, indanthrone, anthrapyrimidine, flavanthrone, thioindigo, anthraquinone, perinone, perylene, etc.), isoindolinone, metal complex, quinophthalone, and diketopyrrolopyrrole.

[0041] More specifically, in terms of the CI color index, black pigments include CI Pigment Black 1, 6, 7, 9, 10, 11, 28, 26, 31, and the like.

[0042] Examples of white pigments include CI Pigment White 5, 6, 7, 12, and 28.

[0043] Examples of yellow pigments include CI 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, and 213.

[0044] Blue or cyan pigments include CI Pigment Blue 1, 2, 14, 15, 15:1, 15:2, 15:3, 15:4, 60, 62, and the like.

[0045] Red or crimson pigments include CI Pigment RED 1, 3, 5, 19, 21, 22, 31, 38, 42, 43, 48:1, 48:2, 48:3, 48:4, 48:5, 49:1, 50, 52, 53:1, 57:1, 57:2, 58:4, 63:1, 81, 81:1, 81:2, 81:3, 81:4, 83, 90, 104, 108, 11 2, 114, 122, 144, 146, 148, 149, 150, 166, 168, 169, 170, 172, 173, 176, 177, 178, 184, 185, 187, 193, 202, 209, 214, 242, 254, 255, 264, 266, 269, CI Pigment Violet 19, etc.

[0046] Green pigments include CI Pigment Green 1, 2, 3, 4, 7, 8, 10, 15, 17, 26, 36, 45, 50, and the like.

[0047] Purple pigments include CI Pigment Violet 1, 2, 3, 4, 5:1, 12, 13, 15, 16, 17, 19, 23, 25, 29, 31, 32, 36, 37, 39, and 42. Orange pigments include CI Pigment Orange 13, 16, 20, 34, 36, 38, 39, 43, 51, 61, 63, 64, 74, and the like.

[0048] In the present invention, the above pigments may be used alone or in combination of two or more.

[0049] The colorant in the present invention can be used in any content as long as the desired concentration can be reproduced, and is preferably used in an amount of 5 to 60% by mass based on the total mass of the composition.

[0050] <Extender pigment> An extender pigment may be added to the composition of the present invention. As the body pigment in the present invention, inorganic fine particles are preferably used.

[0051] Specific examples of extender pigments include inorganic extender pigments such as lime carbonate powder, 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, etc., as well as silicone, glass beads, etc. These inorganic fine particles can add effects such as adjusting the flowability of the composition, preventing misting, and preventing penetration into printing substrates such as paper.

[0052] The extender pigment in the present invention can be used in any content as long as it is possible to impart the intended effects, such as adjusting flowability, preventing misting, and preventing penetration into printing substrates such as paper, and it is preferable that the content be 0.1 to 10% by mass based on the total mass of the composition.

[0053] <Additives> Depending on the purpose, the composition of the present invention may further contain various additives such as an anti-friction agent, an anti-blocking agent, a slipping agent, etc. Various additives can be added to the composition by a conventional method. When various additives are added to the composition of the present invention, it is preferable to adjust the amount of each additive to a range that does not inhibit the effects of other materials. The amount of each additive is preferably 20 mass % or less of the total amount of the composition.

[0054] <Photopolymerization initiator> The composition of the present invention may contain a photopolymerization initiator. The polymerization initiator in the present invention is a compound that undergoes a chemical change and generates radicals through the action of light or through interaction with the electronically excited state of the sensitizing dye, and among them, a photoradical polymerization initiator is preferable from the viewpoint of being able to initiate polymerization by exposure to light.

[0055] The photopolymerization initiator that can be used in the present invention is not particularly limited, and any known photopolymerization initiator can be used. Specific examples include benzophenone compounds, dialkoxyacetophenone compounds, α-hydroxyalkylphenone compounds, α-aminoalkylphenone compounds, acylphosphine oxide compounds, and thioxanthone compounds. The photopolymerization initiator may be used alone or in combination of two or more kinds.

[0056] Examples of the benzophenone-based compounds include benzophenone, 4-methylbenzophenone, 4-phenylbenzophenone, 4,4'-bis(diethylamino)benzophenone, 4,4'-bis(dimethylamino)benzophenone, and [4-(methylphenylthio)phenyl]-phenylmethanone.

[0057] Examples of the dialkoxyacetophenone compounds include 2,2-dimethoxy-2-phenylacetophenone, dimethoxyacetophenone, and diethoxyacetophenone.

[0058] Examples of the α-hydroxyalkylphenone compounds include 1-hydroxy-cyclohexyl phenyl ketone, 2-hydroxy-2-methyl-1-phenyl-propan-1-one, 1-[4-(2-hydroxymethoxy)-phenyl]-2-hydroxy-2-methyl-1-propan-1-one, and 2-hydroxy-1-{4-[4-(2-hydroxy-2-methyl-propionyl)-benzyl]phenyl}-2-methyl-propan-1-one.

[0059] Examples of the α-aminoalkylphenone compounds include 2-methyl-1-[4-(methoxythio)-phenyl]-2-morpholinopropan-1-one, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-butanone-1, and 2-(dimethylamino)-2-[(4-methylphenyl)methyl]-1-[4-(4-morpholinyl)phenyl]-1-butanone.

[0060] Examples of the acylphosphine oxide compound include diphenylacylphenylphosphine oxide, 2,4,6-trimethylbenzoyl-diphenylphosphine oxide, bis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide, 2,4,6-trimethylbenzoyl-bis(4-methylphenyl)phosphine oxide, and ethoxyphenyl(2,4,6-trimethylbenzoyl)phosphine oxide.

[0061] Examples of the thioxanthone compounds include 2-isopropylthioxanthone, 2,4-dimethylthioxanthone, and 2,4-diethylthioxanthone.

[0062] The content of the photopolymerization initiator is preferably 1 to 20% by mass, and more preferably 5 to 15% by mass, based on the total amount of the ink.

[0063] When the composition of the present invention is cured by irradiating it with ultraviolet light, it is sufficient to add a photopolymerization initiator to the composition. In order to further improve the curability, a photosensitizer can also be used in combination. Examples of photosensitizers 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.

[0064] <Photopolymerization inhibitor> The composition of the present invention may contain a photopolymerization inhibitor, which can provide excellent storage stability.

[0065] From the viewpoint of storage stability, the photopolymerization inhibitor in the present invention preferably contains one selected from the group consisting of nitroso-based compounds, phenol-based compounds, quinone-based compounds, and piperidine-based compounds.

[0066] Examples of nitroso compounds include nitrosobenzene, aluminum N-nitrosophenylhydroxylamine, tri-p-nitrophenylmethyl, picric acid, cupferron, butyraldoxime, methyl ethyl ketoxime, and cyclohexanone oxime.

[0067] Examples of the phenol-based compounds include (alkyl)phenols, p-methoxyphenol, o-isopropylphenol, catechol, resorcin, t-butylcatechol, pyrogallol, dibutylcresol, and guaiacol.

[0068] Examples of quinone compounds include hydroquinone, t-butylhydroquinone, p-benzoquinone, and 2,5-di-tert-butyl-p-benzoquinone.

[0069] Examples of the piperidine compounds include phenothiazine.

[0070] In addition, the photopolymerization inhibitor in the present invention may be used in combination with photopolymerization inhibitors other than the above-mentioned nitroso compounds, phenolic compounds, quinone compounds, and piperidine compounds (also referred to as "other photopolymerization inhibitors"). Specific examples of other photopolymerization inhibitors include 1,1-picrylhydrazyl, dithiobenzoyl disulfide, N-(3-oxyanilino-1,3-dimethylbutylidene)aniline oxide, cyclohexanone oxime cresol, and the like.

[0071] The content of the photopolymerization inhibitor is preferably from 0.05 to 5.0% by mass, and more preferably from 0.1 to 1.0% by mass, based on the total mass of the composition.

[0072] It is preferable that the active energy ray-curable composition of the present invention does not substantially contain an organic solvent. In the present invention, "substantially does not contain" means that it is not intentionally added and the content due to unintentional addition is less than 1 mass%. Unintentional addition includes cases where it is contained in trace amounts in each raw material, contamination in the composition production process, the print production process, etc. Organic solvents used as viscosity modifiers in printing inks are of concern as they may contain MOSH / MOAH, which are persistent organic pollutants. Furthermore, the absence of volatile components (Non-VOC) is expected to reduce the environmental load and improve work safety. Therefore, in the present invention, it is preferable that the ink is substantially free of organic solvents.

[0073] In this specification, the active energy rays typically include ultraviolet rays, electron beams, X-rays, ionizing radiation such as α-rays, β-rays, and γ-rays, microwaves, high frequency waves, and the like, but may be any energy species capable of generating radical active species, including visible light, infrared light, and laser beams. Examples of devices that emit 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.

[0074] The composition of the present invention can be applied to various substrates and printed materials such as various printed materials for books, various printed materials for packaging such as paper, various printed materials for plastics, printed materials for stickers / labels, fine art printed materials, and printed materials for metals (fine art printed materials, printed materials for beverage cans, printed materials for canned food such as canned foods).

[0075] <Laminate> The laminate of the present invention is obtained by printing or coating the composition of the present invention on a substrate and curing it with active energy rays. There is no particular limitation on the substrate, and any known substrate can be used. Specific examples include coated paper such as art paper, coated paper, and cast paper, uncoated paper such as fine paper, medium-quality paper, and newsprint, synthetic paper such as Yupo paper, and plastic films such as PET (polyethylene terephthalate), PP (polypropylene), and OPP (biaxially oriented polypropylene).

[0076] Methods for printing or coating the composition of the present invention on a substrate include a roll coater, a gravure coater, a flexo coater, an air doctor coater, a blade coater, an air knife coater, a squeeze coater, an impregnation coater, a transfer roll coater, a kiss coater, a curtain coater, a cast coater, a spray coater, a die coater, offset printing (normal lithographic printing using dampening water and waterless lithographic printing not using dampening water), flexo printing, gravure printing, screen printing, and the like. EXAMPLES

[0077] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples. In the present specification, "parts" refers to parts by mass, and "%" refers to % by mass.

[0078] (Varnish manufacturing example 1) In a four-neck flask equipped with a stirrer, a Dean-Stark tube, a thermometer, and a gas inlet tube, 35 parts of Daiso DAP A (weight average molecular weight 30,000, manufactured by Osaka Soda Co., Ltd.), 10 parts of MIRAMER M600 (dipentahexaacrylate, manufactured by Bigen Specialty Chemical Co., Ltd.), and 55 parts of LAROMER LR8863 (trimethylolpropane EO-modified (3) triacrylate, manufactured by BASF) were placed, heated to 100°C with stirring, and stirred and melted at 100°C for 2 hours to obtain Daiso DAP-A varnish.

[0079] (Varnish manufacturing example 2) In a four-neck flask equipped with a stirrer, a Dean-Stark tube, a thermometer, and a gas inlet tube, 50 parts of Petrotac 90 (weight average molecular weight 1,600, manufactured by Tosoh Corporation), 30 parts of MIRAMER M360 (trimethylolpropane PO-modified (3) acrylate, manufactured by Bigen Specialty Chemical Co., Ltd.), and 20 parts of MIRAMER M220 (tripropylene glycol diacrylate, manufactured by Bigen Specialty Chemical Co., Ltd.) were placed, heated to 100°C with stirring, and stirred and melted at 100°C for 2 hours to obtain a Petrotac 90 varnish.

[0080] The active energy ray-curable compositions of Examples 1 to 68 and Comparative Examples 1 to 8 were obtained by milling in a triple roll mill according to the compositions in Table 1. The evaluation results of the obtained active energy ray-curable compositions are also shown in Table 1.

[0081] [Table 1]

[0082] [Table 1]

[0083] [Table 1]

[0084] [Table 1]

[0085] [Table 1]

[0086] [Table 1]

[0087] [Table 1]

[0088] Details of the materials listed in Table 1 are given below. <(Meth)acrylate compounds> · MIRAMER M600: Dipentaerythritol hexaacrylate, manufactured by Bigen Specialty Chemical Co., Ltd. MIRAMER M410: Ditrimethylolpropane tetraacrylate, manufactured by Bigen Specialty Chemical Co., Ltd. LAROMER LR8863: Trimethylolpropane EO modified (3) triacrylate, manufactured by BASF ETERMER 2381: Trimethylolpropane PO modified (3) triacrylate, manufactured by Choko Materials Industry Co., Ltd. EBECRYL OTA480: Glycerin PO modified (3) triacrylate, manufactured by Daicel Allnex Co., Ltd. TPGDA: Tripropylene glycol diacrylate, manufactured by Daicel Allnex Co., Ltd. <Coloring agent> Carbon black: Mitsubishi Chemical Corporation, Carbon Black MA11 <Photopolymerization initiator> Omnirad379EG: iGM RESINS, 2-dimethylamino-2-(4-methylbenzyl)-1-(4-morpholin-4-yl-phenyl)-butan-1-one ·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

[0089] <Evaluation of active energy ray-curable composition> The examples and comparative examples were evaluated according to the following methods.

[0090] <How to measure dot gain> Printing was carried out at a speed of 10,000 sheets per hour under the following conditions using an offset sheet-fed printing machine LITHRONE L426 (Komori Corporation). The amount of expansion (dot gain) of 50% dots on the plate surface during continuous printing of 5,000 sheets was compared. A dot gain rating of 2 or higher is a practically acceptable level. A rating of 3 or higher is even more preferable, as it provides clear printed matter. (Evaluation Criteria) 5: Dot gain of less than 17%, providing extremely clear prints that far exceed market demands 4: Dot gain is between 17% and 19%, providing clear prints that fully meet market demands. 3: Dot gain is between 19% and 22%, providing prints that meet the market standards. 2: Dot gain is 22% or more but less than 25%, which is the lower limit acceptable to the market. 1: Dot gain is over 25%, not meeting market demand (Printing conditions) Printing machine: LITHRONE26 (manufactured by Komori Corporation) Paper: Oji Paper Co., Ltd., OK Topcoat+ (79.1g / m 2 ) Print speed: 10,000 sheets / hour Lamp: Eye Graphics metal halide lamp (output 120W / cm, 3 lamps used)

[0091] <Method of evaluating liquidity> 2.1cc of ink was poured onto a metal plate with a hemispherical depression, left to stand for 2 minutes, then tilted at 60 degrees and the length of ink that flowed over 10 minutes was measured and rated based on the following evaluation criteria. The higher the value, the less ink was tightly packed and the better the fluidity. A rating of 2 or more is a practically acceptable level, with 3 or more being more preferable. (Evaluation Criteria) 4: 50mm or more 3: 35mm to less than 50mm 2: 20mm to less than 35mm 1: Less than 20mm

[0092] As shown in Table 1, in Examples 1 to 68, both the dot gain and fluidity were good and practically problem-free. Moreover, in the Examples containing 3% by mass or less of a carboxylic acid compound having a ring structure in the molecule, the dot gain was particularly good. On the other hand, Comparative Example 1, which did not contain a carboxylic acid compound, had poor dot gain. Comparative Examples 2 and 3 had poor dot gain because they were not carboxylic acid compounds, although their molecular weights were 500 or less. Furthermore, as shown by Comparative Examples 4 to 8, when the amount of the carboxylic acid compound added exceeded 3% by mass, the dot gain and fluidity were poor.

Claims

1. An active energy ray-curable composition comprising a (meth)acrylate compound (A) and dehydroabietic acid, The content of the dehydroabietic acid is 0.001% by mass or more and 3% by mass or less based on the total amount of the composition, An active energy ray-curable composition for use in any printing method selected from the group consisting of offset printing, flexographic printing, gravure printing, and screen printing (excluding the case where the composition is for use in a color filter).

2. The active energy ray-curable composition according to claim 1 , further comprising a resin (C).

3. The active energy ray-curable composition according to claim 1 , further comprising a colorant (D).

4. The active energy ray-curable composition according to claim 2, wherein the content of the resin (C) is 2 to 40 mass% based on the total amount of the composition.

5. The active energy ray curable composition according to claim 1, for use on any substrate selected from the group consisting of coated paper, uncoated paper, synthetic paper, and plastic film.

6. A laminate comprising a substrate and a layer obtained by curing the active energy ray-curable composition according to any one of claims 1 to 5 with active energy rays.

7. The laminate described in claim 6, which is any printed material selected from the group consisting of printed materials for books, printed materials for packaging, printed materials for plastics, printed materials for stickers / labels, art printed materials, and printed materials for metal.