Active energy ray-curable composition and laminate

Abstract

An active energy ray-curable composition which contains (A) a (meth) acrylate compound and (B) a carboxylic acid or carboxylic acid anhydride that does not have a (meth) acryloyl group and that has a molecular weight of 500 or less, 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 relative to the total amount of the composition.

Description

Technical Field

[0001] Embodiments of the present invention relate to an active energy ray-curable composition used in packages and the like, and more particularly, to an active energy ray-curable composition capable of providing a clear printed matter (a laminate having a printed layer). Background Art

[0002] Active energy ray-curable inks are solvent-free and are instantaneously cured and dried by active energy rays. Therefore, printed matters with excellent environmental responsiveness, printing workability, and high quality can be obtained. Therefore, they are widely used in the fields of printed information such as magazines and leaflets to the field of packages for food packaging such as paper boxes.

[0003] In recent years, the requirements for labor saving, labor reduction, automation, and high speed in printing have been gradually increasing, especially the printing speed has been increasing at a high rate. Moreover, inks and varnishes that can stably obtain high-quality printed matters without failure and for a long time under various printing conditions are desired, and various improvements to inks have been studied so far.

[0004] Patent Document 1 discloses an active energy ray-curable ink containing a metal complex and a compound having a polar group. The disclosed ink was evaluated for the presence or absence of stains during printing, but a clear printed matter that meets market requirements was not obtained.

[0005] Prior Art Documents

[0006] Patent Documents

[0007] Patent Document 1: Japanese Unexamined Patent Application Publication No. 2021-195503 Summary of the Invention

[0008] Problems to be Solved by the Invention

[0009] The present invention provides an active energy ray-curable composition that can obtain a printed matter with little collapse of the dot shape and clear, and has excellent fluidity, and a printed matter using the same.

[0010] Means for Solving the Problems

[0011] The present inventors conducted in-depth research to solve the above problems, and as a result, found that the above problems can be solved by the active energy ray-curable composition shown below, and thus completed the present invention.

[0012] That is, the embodiments of the present invention include the following. However, the present invention is not limited to the following embodiments.

[0013] [1]A radiation curable composition comprising a (meth)acrylate compound (A) and a carboxylic acid or carboxylic anhydride (B) having no (meth)acryloyl group and a molecular weight of 500 or less.

[0014] The content of the carboxylic acid or carboxylic anhydride (B) having no (meth)acryloyl group and a molecular weight of 500 or less is 3% by mass or less based on the total amount of the composition.

[0015] [2]The radiation curable composition according to the above [1], wherein the carboxylic acid or carboxylic anhydride (B) having no (meth)acryloyl group and a molecular weight of 500 or less has a cyclic hydrocarbon structure in the molecule.

[0016] [3]The radiation curable composition according to the above [1] or [2], wherein the carboxylic acid or carboxylic anhydride (B) having no (meth)acryloyl group and a molecular weight of 500 or less contains 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.

[0017] [4]The radiation curable composition according to any one of the above [1] to [3] further contains a resin (C).

[0018] [5]The radiation curable composition according to any one of the above [1] to [4] further contains a colorant (D).

[0019] [6]The radiation curable composition according to the above [4] or [5], wherein the content of the resin (C) is 2 to 40% by mass based on the total amount of the composition.

[0020] [7]A laminate having a substrate and a layer obtained by curing the radiation curable composition according to any one of the above [1] to [6] with radiation.

[0021] The disclosure of the present application is related to the subject matter described in Japanese Patent Application No. 2023-145706 filed on September 8, 2023, and the entire disclosure thereof is incorporated herein by reference.

[0022] Advantages of the Invention

[0023] According to the present invention, it is possible to provide a radiation curable composition that can obtain a printed matter with little collapse and distinct dot shape and has excellent fluidity, and a printed matter using the same. Detailed Description

[0024] 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 can be made without departing from the gist of the present invention.

[0025] The terms used in this specification will be described. “(Meth)acrylate” means acrylate and / or methacrylate. “Actinic energy ray” means an energy ray such as ultraviolet ray having a property of causing a chemical change such as a chemical reaction in the irradiated substance. In addition, “PO” represents “propylene oxide” and “EO” represents “ethylene oxide”.

[0026] <(Meth)acrylate compound (A)>

[0027] The actinic energy ray curable composition (hereinafter, also referred to as “composition”) according to one embodiment of the present invention contains a (meth)acrylate compound (A).

[0028] The above-mentioned (meth)acrylate compound (A) is a compound having one or more (meth)acryloyl groups in the molecule.

[0029] Specific examples of the (meth)acrylate compound (A) include the following compounds:

[0030] 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, isopentyl (meth)acrylate, 2-phenoxyethyl (meth)acrylate, isodecyl (meth)acrylate, 3,3,5-trimethylcyclohexanol (meth)acrylate, cyclohexyl (meth)acrylate, isobornyl (meth)acrylate, norbornyl (meth)acrylate, dicyclopentyl (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;

[0031] 1,3 - butanediol 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, 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, dimethylol tricyclodecane di(meth)acrylate, EO - modified(4) bisphenol A di(meth)acrylate, PO - modified(4) bisphenol A di(meth)acrylate, cyclohexane dimethanol di(meth)acrylate, dimethylol tricyclodecane di(meth)acrylate, dicyclopentyl di(meth)acrylate, tris(2 - hydroxyethyl) isocyanurate di(meth)acrylate and other difunctional (meth)acrylate compounds having 2 (meth)acryloyl groups;

[0032] trimethylolpropane tri(meth)acrylate, EO - modified(3) trimethylolpropane tri(meth)acrylate, PO - modified(3) trimethylolpropane tri(meth)acrylate, ε - caprolactone - modified tris(2 - acryloyloxyethyl) isocyanurate, ethoxylated isocyanuric acid tri(meth)acrylate, tris(2 - hydroxyethyl) isocyanurate tri(meth)acrylate, pentaerythritol tri(meth)acrylate, PO - modified(3) glycerol triacrylate and other trifunctional (meth)acrylate compounds having 3 (meth)acryloyl groups;

[0033] pentaerythritol tetra(meth)acrylate, bis(trimethylolpropane) tetra(meth)acrylate and other tetrafunctional (meth)acrylate compounds having 4 (meth)acryloyl groups;

[0034] dipentaerythritol penta(meth)acrylate and other pentafunctional (meth)acrylate compounds having 5 (meth)acryloyl groups; and

[0035] dipentaerythritol hexa(meth)acrylate and other hexafunctional (meth)acrylate compounds having 6 (meth)acryloyl groups.

[0036] In addition, as the (meth)acrylate compound (A), urethane acrylate, polyester acrylate, epoxy acrylate, etc. can also be used.

[0037] Urethane acrylate is, for example, a substance obtained by reacting a diisocyanate with a (meth)acrylate having a hydroxyl group, or a substance obtained by reacting a urethane prepolymer containing an isocyanate group, which is obtained by reacting a polyol and a polyisocyanate under conditions where the isocyanate group is in excess, with a (meth)acrylate having a hydroxyl group, etc. Alternatively, it can also be obtained by reacting a hydroxyl group-containing urethane prepolymer, which is obtained by reacting a polyol and a polyisocyanate under conditions where the hydroxyl group is in excess, with a (meth)acrylate having an isocyanate group.

[0038] Polyester acrylate can be obtained, for example, by reacting a polyester polycarboxylic acid obtained by polycondensing a polybasic acid and a polyol with a (meth)acrylate containing a hydroxyl group, etc.

[0039] Epoxy acrylate includes, for example, epoxy acrylate in which the glycidyl group of an epoxy resin is esterified with (meth)acrylic acid to make the functional group a (meth)acrylate group, such as a (meth)acrylic acid adduct of bisphenol A type epoxy resin, a (meth)acrylic acid adduct of novolac type epoxy resin, etc.

[0040] The above-mentioned (meth)acrylate compound (A) can be used alone as one kind, or two or more kinds can be used in combination. In some embodiments, from the viewpoint of the strength of the cured coating film, the above-mentioned (meth)acrylate compound (A) is preferably a (meth)acrylate compound having two or more (meth)acryloyl groups, and more preferably a (meth)acrylate compound having three or more (meth)acryloyl groups.

[0041] In some embodiments, the (meth)acrylate compound (A) preferably contains at least one selected from the group consisting of tripropylene glycol di(meth)acrylate, EO-modified (3) trimethylolpropane tri(meth)acrylate, PO-modified (3) trimethylolpropane tri(meth)acrylate, PO-modified (3) glycerol triacrylate, bis(trimethylolpropane) tetra(meth)acrylate, and dipentaerythritol hexa(meth)acrylate, and more preferably contains two or more kinds.

[0042] In some embodiments, the (meth)acrylate compound (A) preferably contains two or more selected from the group consisting of EO-modified (3) trimethylolpropane tri(meth)acrylate, PO-modified (3) trimethylolpropane tri(meth)acrylate, PO-modified (3) glycerol triacrylate, bis(trimethylolpropane) tetra(meth)acrylate, and dipentaerythritol hexa(meth)acrylate.

[0043] Among them, the above-mentioned (meth)acrylate compound (A) preferably contains at least one selected from EO-modified (3) trimethylolpropane tri(meth)acrylate, PO-modified (3) trimethylolpropane tri(meth)acrylate, and PO-modified (3) glycerol triacrylate, and at least one selected from the group consisting of bis(trimethylolpropane) tetra(meth)acrylate and dipentaerythritol hexa(meth)acrylate. In some embodiments, the above-mentioned (meth)acrylate compound (A) preferably contains EO-modified (3) trimethylolpropane tri(meth)acrylate and bis(trimethylolpropane) tetra(meth)acrylate.

[0044] From the viewpoint of curability, the content of the above-mentioned (meth)acrylate compound (A) is preferably 20 to 95% by mass, more preferably 25 to 90% by mass, based on the total amount of the composition.

[0045] <Carboxylic acid or carboxylic anhydride (B) having no (meth)acryloyl group with a molecular weight of 500 or less>

[0046] In the composition of the present embodiment, the content of the carboxylic acid or carboxylic anhydride (B) having no (meth)acryloyl group with a molecular weight of 500 or less is 3% by mass or less based on the total amount of the composition.

[0047] In the present embodiment, the carboxylic acid or carboxylic anhydride (B) having no (meth)acryloyl group with a molecular weight of 500 or less may specifically be a compound having one or more carboxylic acids described below.

[0048] Examples of the compound having one carboxylic acid include aromatic monocarboxylic acids such as benzoic acid, methylbenzoic acid, tert-butylbenzoic acid, naphthoic acid, and o-benzoylbenzoic acid; resin acids such as abietic acid, neoabietic acid, palustric acid, dehydroabietic acid, pimaric acid, isopimaric acid, sandaracopimaric acid, and pinus elliottii var. elliottii acid; stearic acid, palmitic acid, oleic acid, and linoleic acid.

[0049] Examples of the compound 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, alkenyl succinic acids such as dodecenyl succinic acid and pentadecenyl succinic acid, phthalic acid, terephthalic acid, isophthalic acid, trimellitic acid, pyromellitic acid, maleic acid, fumaric acid, citraconic acid, itaconic acid, crotonic acid, isocrotonic acid, dihydroagathenic acid, and their acid anhydrides.

[0050] The carboxylic acid or carboxylic anhydride (B) having no (meth)acryloyl group and having a molecular weight of 500 or less can be used alone as one kind, or two or more kinds can be used in combination.

[0051] By making the molecular weight of the above compound 500 or less, the sharpness of the printed paper surface can be exhibited without impairing the fluidity of the composition. In some embodiments, the molecular weight of the above compound can be 400 or less, can be 350 or less, or can be 300 or less. In some embodiments, the molecular weight of the above compound can be 284.5 or less. Although not particularly limited, the molecular weight of the above compound can be 50 or more.

[0052] Furthermore, from the viewpoints of the fluidity of the composition and the printing sharpness, the carboxylic acid or carboxylic anhydride (B) having no (meth)acryloyl group and having a molecular weight of 500 or less preferably contains a carboxylic acid compound having a cyclic hydrocarbon structure in the structure (in the molecule). The cyclic hydrocarbon structure can be either an aromatic ring or an alicyclic structure.

[0053] Among the carboxylic acid compounds having a cyclic hydrocarbon structure in the molecule, as the compound having one carboxylic acid, there can be mentioned aromatic monocarboxylic acids such as benzoic acid, methylbenzoic acid, tert-butylbenzoic acid, naphthoic acid, o-benzoylbenzoic acid, and resin acids such as abietic acid, neoabietic acid, longifolene acid, dehydroabietic acid, pimaric acid, isopimaric acid, sandaracopimaric acid, and pinus elliottii var. elliottii acid. Among them, at least one selected from the group consisting of benzoic acid, methylbenzoic acid, tert-butylbenzoic acid, abietic acid, and dehydroabietic acid can be appropriately used.

[0054] Among the carboxylic acid compounds having a cyclic hydrocarbon structure in the molecule, as the compound having two or more carboxylic acids, there can be mentioned 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, phthalic acid, terephthalic acid, isophthalic acid, trimellitic acid, pyromellitic acid, maleic acid, fumaric acid, dihydroagathic acid, and their acid anhydrides, etc. Among them, at least one selected from the group consisting of maleic anhydride, 1,2,3,6-tetrahydrophthalic anhydride, phthalic anhydride, 1,4-cyclohexanedicarboxylic acid, isophthalic acid, terephthalic acid, and trimellitic anhydride can be appropriately used.

[0055] In some embodiments, from the viewpoints of compatibility with the (meth)acrylate compound and print sharpness, the carboxylic acid or carboxylic anhydride (B) having no (meth)acryloyl group and a molecular weight of 500 or less is preferably a carboxylic acid compound having a cyclic hydrocarbon structure in the molecule. As the carboxylic acid compound having a cyclic hydrocarbon structure, it preferably contains one or more selected from the group consisting of tert-butylbenzoic acid, benzoic acid, methylbenzoic acid, rosin acid, dehydroabietic acid, maleic anhydride, 1,2,3,6-tetrahydrophthalic anhydride, phthalic anhydride, 1,4-cyclohexanedicarboxylic acid, isophthalic acid, terephthalic acid, and trimellitic anhydride. As the carboxylic acid compound having a cyclic hydrocarbon structure, it is more preferably one or more selected from the group consisting of benzoic acid, rosin acid, dehydroabietic acid, maleic anhydride, 1,2,3,6-tetrahydrophthalic anhydride, phthalic anhydride, isophthalic acid, and terephthalic acid.

[0056] In some embodiments, the carboxylic acid compound having a cyclic hydrocarbon structure may be a compound having one carboxylic acid, and among them, benzoic acid, rosin acid, and dehydroabietic acid are preferred, and benzoic acid and dehydroabietic acid are more preferred. In some embodiments, the carboxylic acid compound having a cyclic hydrocarbon structure may be a compound having two or more carboxylic acids, and among them, 1,2,3,6-tetrahydrophthalic anhydride and phthalic anhydride are preferred.

[0057] The content of the carboxylic acid or carboxylic anhydride (B) having no (meth)acryloyl group and a molecular weight of 500 or less is 3% by mass or less relative to the total amount of the composition. When it exceeds 3% by mass, the compatibility with the (meth)acrylate compound (A) deteriorates, and there is a tendency for the fluidity to deteriorate.

[0058] The content of the carboxylic acid or carboxylic anhydride (B) having no (meth)acryloyl group and a molecular weight of 500 or less may be 0.0005% by mass or more, 0.001% by mass or more, 0.003% by mass or more, and may be 3% by mass or less, 2% by mass or less, 1% by mass or less. The content of the above (B) is preferably 0.001% by mass to 2% by mass, and more preferably 0.003% by mass to 1% by mass.

[0059] By adjusting the content of the above (B) to the above range, the fluidity and the sharpness of the printed matter become appropriate. Although not bound by theory, when the carboxylic acid or carboxylic anhydride (B) having no (meth)acryloyl group and a molecular weight of 500 or less is present in the composition in the above range, it is presumed to function in a manner that affects the compatibility of the (meth)acrylate compound and improves the cohesion of the ink. If the cohesion of the ink is exhibited during printing, it appropriately acts to increase the dot gain, and a sharp printed matter is easily obtained.

[0060] <Resin (C)>

[0061] The composition of the present embodiment preferably contains a resin (C). By containing the resin (C), the fluidity becomes appropriate.

[0062] In the present embodiment, as the resin (C), it preferably has excellent compatibility with the (meth)acrylate compound. Specific examples of the resin (C) include diallyl phthalate resins, rosin-modified resins, polyvinyl chloride, poly(meth)acrylates, epoxy resins, polyester resins, polyurethane resins, cellulose derivatives (such as ethyl cellulose, cellulose acetate, nitrocellulose), vinyl chloride-vinyl acetate copolymers, polyamide resins, polyvinyl acetal resins, alkyd resins, petroleum resins, urea resins, synthetic rubbers such as butadiene-acrylonitrile copolymers, and the like.

[0063] Among them, from the viewpoint of fluidity, it is preferable to use one or more selected from the group consisting of diallyl phthalate resins, rosin-modified resins, epoxy resins, polyester resins, polyurethane resins, alkyd resins, and petroleum resins.

[0064] From the viewpoint of the fluidity of the active energy ray-curable composition, the content of the resin (C) is preferably 2 to 40% by mass, more preferably 3 to 30% by mass, based on the total amount of the composition. In some embodiments, the content of the resin (C) can be 10 to 30% by mass, or can be 10 to 20% by mass, based on the total amount of the composition.

[0065] From the viewpoints of compatibility with the (meth)acrylate compound and fluidity, the weight-average molecular weight of the resin (C) is preferably 1,000 to 50,000, more preferably 1,500 to 40,000.

[0066] <Colorant (D)>

[0067] In the composition of the present embodiment, a colorant (D) may be further used.

[0068] As the colorant (D), at least one of a pigment and a dye can be used, but from the viewpoint of light resistance, a pigment is preferably used.

[0069] In the present embodiment, there is no particular limitation on the pigment, and known pigments can be used. Either an inorganic pigment or an organic pigment can be used as the pigment.

[0070] 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.

[0071] Examples of organic pigments include soluble azo pigments such as β-naphthol, β-hydroxynaphthoic acid, β-hydroxynaphthoic acid aniline, acetoacetanilide, and pyrazolone; insoluble azo pigments such as β-naphthol, β-hydroxynaphthoic acid aniline, acetoacetanilide monoazo, acetoacetanilide disazo, and pyrazolone; phthalocyanine pigments such as copper phthalocyanine blue, halogenated (e.g., chlorinated or brominated) copper phthalocyanine blue, sulfonated copper phthalocyanine blue, and metal-free phthalocyanine; polycyclic pigments and heterocyclic pigments such as quinacridone, dioxazine, threne (pyranthrone, anthraquinone, indanthrone, anthrapyrimidine, flavonol, thioindigo, anthraquinone, perinone, and perylene), isoindolinone, metal complex, quinophthalone, and diketopyrrolopyrrole.

[0072] More specifically, when indicated by CI Pigment Index, examples of the black pigment include CI Pigment Black 1, 6, 7, 9, 10, 11, 28, 26, and 31.

[0073] Examples of the white pigment include CI Pigment White 5, 6, 7, 12, and 28.

[0074] Examples of the yellow pigment 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.

[0075] Examples of the blue or cyan pigment include CI Pigment Blue 1, 2, 14, 15, 15:1, 15:2, 15:3, 15:4, 60, and 62.

[0076] Examples of the magenta or red pigment 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, 1 04, 108, 112, 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.

[0077] Examples of the green pigment include C.I. Pigment Green 1, 2, 3, 4, 7, 8, 10, 15, 17, 26, 36, 45, 50, etc.

[0078] Examples of the purple pigment 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.

[0079] Examples of the orange pigment include C.I. Pigment Orange 13, 16, 20, 34, 36, 38, 39, 43, 51, 61, 63, 64, 74, etc.

[0080] In the present invention, the above pigments may be used alone or in combination of two or more.

[0081] In the present embodiment, the colorant can be used in any content as long as it can reproduce the target concentration, and is preferably 5 to 60% by mass based on the total mass of the composition.

[0082] <Fine particles>

[0083] The composition of the present embodiment may further contain fine particles. When fine particles are used, effects such as adjusting the fluidity of the composition, preventing ink splashing, and preventing penetration into printing substrates such as paper can be added. The fine particles can be extender pigments, silicone, glass beads, etc., and extender pigments can be suitably used.

[0084] (Extender pigment)

[0085] Specific examples of the extender pigment include extender pigments such as limestone powder, precipitated calcium carbonate, precipitated barium sulfate, gypsum, clay (China Clay), titanium oxide, silicon dioxide, diatomaceous earth, talc, kaolin, aluminum oxide white, barium sulfate, aluminum stearate, calcium stearate, calcium carbonate, magnesium carbonate, barite powder, and ground powder. The above extender pigments can also be used as white pigments (colorants).

[0086] In the present embodiment, the content of the extender pigment is not particularly limited. As long as the target effects such as adjusting fluidity, preventing ink splashing, and preventing penetration into printing substrates such as paper can be added, the extender pigment can be used in any content. In some embodiments, the content of the extender pigment is preferably 0.1 to 10% by mass based on the total mass of the composition.

[0087] <Additives>

[0088] The composition of the present embodiment may further contain various additives such as rub resistance agents, anti-blocking agents, and slip agents as additives according to the purpose. The various additives can be added to the composition by conventional methods.

[0089] When adding various additives to the composition, it is preferable to adjust the blending amount within the range that does not hinder the effects of other materials. The blending amount of various additives is preferably 20% by mass or less relative to the total amount of the composition.

[0090] <Photopolymerization initiator>

[0091] The composition of the present embodiment may contain a photopolymerization initiator. The polymerization initiator in the present invention may be a compound that undergoes a chemical change by the action of light or the interaction with the electronically excited state of a sensitizing dye to generate free radicals. Among them, from the viewpoint of being able to initiate polymerization by means such as exposure, a photo radical polymerization initiator is preferred.

[0092] The photopolymerization initiator that can be used in the present embodiment is not particularly limited, and known photopolymerization initiators can be used. As specific examples, benzophenone-based compounds, dialkoxyacetophenone-based compounds, α-hydroxyalkylbenzophenone-based compounds, α-aminoalkylbenzophenone-based compounds, acylphosphine oxide-based compounds, thioxanthone-based compounds, etc. can be cited.

[0093] In addition, the photopolymerization initiator can be used alone or in combination of two or more.

[0094] As the above benzophenone-based compounds, benzophenone, 4-methylbenzophenone, 4-phenylbenzophenone, 4,4'-bis(diethylamino)benzophenone, 4,4'-bis(dimethylamino)benzophenone, [4-(methylphenylthio)phenyl]phenylmethanone, etc. can be cited.

[0095] As the above dialkoxyacetophenone-based compounds, 2,2-dimethoxy-2-phenylacetophenone, dimethoxyacetophenone, diethoxyacetophenone, etc. can be cited.

[0096] As the above α-hydroxyalkylbenzophenone-based compounds, 1-hydroxycyclohexyl phenyl ketone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 1-[4-(2-hydroxy-methoxy)phenyl]-2-hydroxy-2-methyl-1-propan-1-one, 2-hydroxy-1-{4-[4-(2-hydroxy-2-methylpropionyl)benzyl]phenyl}-2-methylpropan-1-one, etc. can be cited.

[0097] As the above α-aminoalkylbenzophenone-based compounds, 2-methyl-1-[4-(methoxythio)phenyl]-2-morpholinopropan-1-one, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)butan-1-one, 2-dimethylamino-2-(4-methylbenzyl)-1-(4-morpholin-4-ylphenyl)-butan-1-one, etc. can be cited.

[0098] Examples of the above acylphosphine oxide compounds 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, ethoxyphenyl(2,4,6-trimethylbenzoyl)phosphine oxide, and the like.

[0099] Examples of the above thioxanthone compounds include 2-isopropylthioxanthone, 2,4-dimethylthioxanthone, 2,4-diethylthioxanthone, and the like.

[0100] Relative to the total amount of the composition (ink), the content of the above photoinitiator is preferably 1 to 20% by mass, more preferably 5 to 15% by mass. In some embodiments, the photoinitiator preferably contains an α-aminoalkylphenone compound and a thioxanthone compound. The photoinitiator preferably contains, for example, 2-dimethylamino-2-(4-methylbenzyl)-1-(4-morpholin-4-ylphenyl)butan-1-one and 2,4-diethylthioxanthone.

[0101] When irradiating the composition of the present embodiment with ultraviolet rays to cure it, it is sufficient to add a photoinitiator to the composition, but in order to further improve the curability, a photosensitizer can also be used in combination.

[0102] Examples of the photosensitizer include amines such as triethanolamine, methyldiethanolamine, dimethylethanolamine, triisopropanolamine, methyl 4-dimethylaminobenzoate, ethyl 4-dimethylaminobenzoate, isopentyl 4-dimethylaminobenzoate, (2-dimethylamino)ethyl benzoate, (n-butoxy)ethyl 4-dimethylaminobenzoate, and 2-ethylhexyl 4-dimethylaminobenzoate.

[0103] <Photo-polymerization inhibitor>

[0104] The composition of the present embodiment may contain a photo-polymerization inhibitor. By containing a photo-polymerization inhibitor, excellent storage stability can be exhibited.

[0105] In the present embodiment, as the photo-polymerization inhibitor, from the viewpoint of storage stability, it is preferably to contain one selected from the group consisting of nitroso compounds, phenolic compounds, quinone compounds, and piperidine compounds.

[0106] Examples of the nitroso compounds include nitrosobenzene, aluminum N-nitrosophenylhydroxylamine, tris(p-nitrophenyl)methyl, picric acid, cupferron, butyraldoxime, methyl ethyl ketoxime, cyclohexanone oxime, and the like.

[0107] Examples of phenolic compounds include (alkyl)phenol, p-methoxyphenol, o-isopropylphenol, catechol, resorcinol, tert-butylcatechol, pyrogallol, dibutylcresol, guaiacol, and the like.

[0108] Examples of quinone compounds include hydroquinone, tert-butylhydroquinone, p-benzoquinone, 2,5-di-tert-butyl-p-benzoquinone, and the like.

[0109] Examples of piperidine compounds include phenothiazine and the like.

[0110] In addition, in the present embodiment, a photopolymerization inhibitor may be used in combination with a photopolymerization inhibitor 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-diphenyl-2-picrylhydrazyl, dibenzoyl disulfide, N-(3-hydroxyanilino-1,3-dimethylbutylene)aniline oxide, cyclohexanone oxime cresol, and the like.

[0111] Based on the total mass of the composition, the content of the photopolymerization inhibitor is preferably 0.05 to 5.0% by mass, more preferably 0.1 to 1.0% by mass.

[0112] The active energy ray-curable composition of the present embodiment preferably substantially does not contain an organic solvent. In the present specification, "substantially does not contain" means that it is not intentionally added and the content of non-intentionally added substances is less than 1% by mass. The case where a trace amount is contained in each raw material, or contaminants in the manufacturing process of the composition and the printing process of the printed matter, etc. belong to non-intentionally added substances.

[0113] Representative organic solvents used as viscosity regulators for printing inks may contain MOSH / MOAH as residual organic pollutants. In addition, by not containing volatile components (Non-VOC), it is possible to expect a reduction in environmental load and an improvement in operation safety. Therefore, the composition of one embodiment of the present invention preferably substantially does not contain an organic solvent.

[0114] <Laminate>

[0115] One embodiment of the present invention relates to a laminate having a substrate and a layer formed of a cured product of the composition of the above embodiment. The laminate of the present embodiment is formed by printing or coating the composition of the present embodiment described above on the substrate to form a printed layer, and then curing the printed layer with active energy rays.

[0116] In this specification, representative examples of active energy rays include ionizing radiation rays such as ultraviolet rays, electron beams, X-rays, α-rays, β-rays, and γ-rays, microwaves, high-frequency waves, etc. However, it is not limited thereto, and any energy type can be used as long as it can generate free radical active species, and it can also be visible light, infrared rays, and laser light.

[0117] As a source for generating ultraviolet rays, for example, LED, ultra-high pressure mercury lamp, high pressure mercury lamp, medium pressure mercury lamp, low pressure mercury lamp, metal halide lamp, xenon lamp, carbon arc lamp, helium-cadmium laser, YAG laser, excimer laser, and argon laser, etc. can be cited.

[0118] As the base material that can be used in the laminate of the present embodiment, there is no particular limitation, and known base materials can be used. Specific examples of the base material include coated papers such as art paper, coated paper, cast-coated paper, uncoated papers such as fine paper, medium paper, newsprint paper, synthetic papers such as YUPO paper, plastic films such as PET (polyethylene terephthalate), PP (polypropylene), OPP (biaxially oriented polypropylene), metal foils, and metal plates used in containers such as cans, etc.

[0119] In some embodiments, the base material can be fine paper, coated paper, art paper, molded paper, thin paper, thick paper, etc. of paper, various synthetic papers, etc. for printing in catalogs, posters, flyers, CD cases, direct mail, brochures, and packaging of cosmetics, beverages, pharmaceuticals, toys, equipment, etc. In some embodiments, the base material can be films, sheets, and cellophane of polyester resin, acrylic resin, vinyl chloride resin, vinylidene chloride resin, polyvinyl alcohol, polyethylene, polypropylene, polyacrylonitrile, ethylene-vinyl acetate copolymer, ethylene-vinyl alcohol copolymer, ethylene-methyl methacrylate copolymer, nylon, polylactic acid, polycarbonate, etc.

[0120] In some embodiments, the base material can be metal foils such as aluminum foil, metal plates such as steel, copper, stainless (Stainless), stainless steel, aluminum, tinplate, tin-free steel, etc., or metal-based substrates provided with a primer layer on the above metal plates.

[0121] As a method of printing or coating the composition of the present embodiment on a substrate, examples include a roll coater, a gravure coater, a flexographic coater, an air doctor coater, a blade coater, an air knife coater, an extrusion 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 (ordinary lithography using dampening solution and waterless lithography without using dampening solution), flexographic printing, gravure printing, screen printing, etc. Among them, from the viewpoint of manufacturing printed matter in the field of packages and the like, methods such as offset printing, flexographic printing, gravure printing, and screen printing are preferred. In these printing methods, the composition of the present embodiment can be suitably used as printing ink.

[0122] The composition of the present embodiment can be suitably used to form a printed layer on various substrates, and can provide various printed matter for books, various printed matter for packaging such as paper, various plastic printed matter, printed matter for seals / labels, art printed matter, metal printed matter (art printed matter, printed matter for beverage cans, printed matter for foods such as cans), etc.

[0123] In some embodiments, the composition of the present embodiment can be used as a top coat for printed matter that requires high gloss, heat resistance, abrasion resistance, etc. The heat resistance and abrasion resistance of the layer (cured layer) formed by the cured product of the composition of the present embodiment are excellent. Therefore, it can be suitably used to form a printed layer for cosmetic cases, paper boxes, labels, catalogs, shopping bags, book covers, posters, etc. used in the packaging of foods, pharmaceuticals, cosmetics, etc., which require immediate label pasting after high-temperature filling treatment and require resistance to label friction during handling in the filling production line process and logistics.

[0124] Examples

[0125] Hereinafter, the present invention will be described more specifically with reference to examples, but the present invention is not limited by these examples. It should be noted that "parts" described in this specification represent parts by mass, and "%" represents mass%.

[0126] (Varnish Production Example 1)

[0127] 35 parts of DAISODAP-A (weight average molecular weight 30,000, manufactured by Osaka Soda Co., Ltd.), 10 parts of MIRAMER M600 (dipentaerythritol hexaacrylate, manufactured by Miyazaki Seika Co., Ltd.), and 55 parts of LAROMER LR8863 (trimethylolpropane EO-modified (3) triacrylate, manufactured by BASF) were added into a four-necked flask equipped with a stirrer, a Dean-Stark tube, a thermometer, and a gas inlet tube, and heated to 100 °C with stirring, and stirred and melted at 100 °C for 2 hours to obtain DAISO DAP-A varnish.

[0128] (Example of Varnish Production 2)

[0129] Into a four-necked flask equipped with a stirrer, Dean-Stark tube, thermometer, and gas inlet tube, add 50 parts of Petrotack 90 (weight-average molecular weight 1,600, manufactured by Tosoh Corporation), 30 parts of MIRAMER M360 (pentaerythritol PO-modified (3) triacrylate, manufactured by MITSUBISHI CHEMICAL CORPORATION), and 20 parts of MIRAMER M220 (tripropylene glycol diacrylate, manufactured by MITSUBISHI CHEMICAL CORPORATION). Heat with stirring to 100 °C and stir and melt at 100 °C for 2 hours to obtain a Petrotack 90 varnish.

[0130] According to the composition in Table 1, the active energy ray-curable compositions of Examples 1 to 68 and Comparative Examples 1 to 8 were obtained by kneading using a three-roll mill. The evaluation results of the obtained active energy ray-curable compositions are shown together in Table 1.

[0131] Table 1

[0132]

[0133] Table 1-1

[0134]

[0135] Table 1-2

[0136]

[0137] Table 1-3

[0138]

[0139] Table 1-4

[0140]

[0141] Table 1-5

[0142]

[0143] Table 1-6

[0144]

[0145] The details of the materials described in Table 1 are as follows.

[0146] <(Meth)acrylate Compound (A)>

[0147] ·MIRAMER M600: Dipentaerythritol hexaacrylate, manufactured by MITSUBISHI CHEMICAL CORPORATION

[0148] ·MIRAMER M410: Bis(trimethylolpropane) tetraacrylate, manufactured by Miramer Co., Ltd.

[0149] ·LAROMER LR8863: Trimethylolpropane EO-modified (3) triacrylate, manufactured by BASF

[0150] ·ETERMER 2381: Trimethylolpropane PO-modified (3) triacrylate, manufactured by Changxing Materials Industry Co., Ltd.

[0151] ·EBECRYL OTA480: Glycerol PO-modified (3) triacrylate, manufactured by Daicel-Allnex Co., Ltd.

[0152] ·TPGDA: Tripropylene glycol diacrylate, manufactured by Daicel-Allnex Co., Ltd.

[0153] <Resin (C)>

[0154] DAISO DAP A varnish: The varnish prepared in Varnish Preparation Example 1

[0155] Petrotack90: The varnish prepared in Varnish Preparation Example 2

[0156] <Colorant (D)>

[0157] ·Carbon black: Manufactured by Mitsubishi Chemical Corporation, carbon black MA11

[0158] <Photoinitiator>

[0159] ·Omnirad379EG: Manufactured by iGM RESINS, 2-dimethylamino-2-(4-methylbenzyl)-1-(4-morpholin-4-ylphenyl)butan-1-one

[0160] ·KAYACURE DETX-S: Manufactured by Nippon Kayaku Co., Ltd., 2,4-diethylthioxanthone

[0161] <Photopolymerization inhibitor>

[0162] ·TBHQ: Manufactured by Seiko Chemical Co., Ltd., phenolic compound, 2-tert-butylhydroquinone

[0163] <Evaluation of the active energy ray-curable composition>

[0164] The examples and comparative examples were evaluated according to the following method.

[0165] <Method for measuring dot gain>

[0166] Printing was performed at a speed of 10,000 sheets per hour using a single-sheet offset printing press LITHRONE L426 (Komori Corporation) under the following conditions. The amount of swelling (dot gain) of 50% dots on the layout during 5,000 consecutive prints was compared. An evaluation of dot gain of "2" or more is a level where there are no practical problems. An evaluation of "3" or more is further preferred and can provide a clear printed matter.

[0167] (Evaluation criteria)

[0168] 5: Can provide a very clear printed matter with a dot gain of less than 17%, far exceeding the market requirements.

[0169] 4: Can provide a clear printed matter with a dot gain of 17% or more and less than 19%, fully meeting the market requirements.

[0170] 3: Can provide a printed matter with a dot gain of 19% or more and less than 22%, at an acceptable level in the market. 2: The dot gain is 22% or more and less than 25%, which is the lower limit level acceptable in the market.

[0171] 1: The dot gain is 25% or more, not meeting the market requirements.

[0172] (Printing conditions)

[0173] Printing press: LITHRONE 26 (manufactured by Komori Corporation)

[0174] Paper: Manufactured by Oji Paper Co., Ltd., OK TOP COAT+ (79.1 g / m 2 )

[0175] Printing speed: 10,000 sheets per hour

[0176] Lamp: Manufactured by EYE GRAPHICS Co., Ltd., metal halide lamp (output 120 W / cm, using 3 lamps)

[0177] <Method for evaluating fluidity>

[0178] Add 2.1 cc of ink to a metal plate with a hemispherical depression. After standing for 2 minutes, tilt it 60 degrees and measure the length of flow in 10 minutes. Evaluate based on the following evaluation criteria. The higher the value, the less the ink bleeding and the better the fluidity. An evaluation of "2" or more is a level where there are no practical problems, and an evaluation of "3" or more is more preferred.

[0179] (Evaluation criteria)

[0180] 4: 50 mm or more

[0181] 3: 35 mm or more and less than 50 mm

[0182] 2: More than 20 mm and less than 35 mm

[0183] 1: Less than 20 mm

[0184] As shown in Table 1, the dot gain and fluidity of Examples 1 to 68 are all practically acceptable and good. In addition, in the examples containing carboxylic acid compounds having a ring structure in the molecule at 3 mass% or less, the dot gain is particularly good as a result.

[0185] On the other hand, the dot gain of Comparative Example 1 without a carboxylic acid compound is poor. The molecular weights of Comparative Examples 2 and 3 are 500 or less, but since they are not carboxylic acid compounds, the dot gain is poor. In addition, as shown in Comparative Examples 4 to 8, when the addition amount of the carboxylic acid compound exceeds 3 mass%, the dot gain and fluidity are poor.

Claims

1. A radiation-curable composition, which is a radiation-curable composition containing a (meth)acrylate compound (A) and a carboxylic acid or carboxylic anhydride (B) having a molecular weight of 500 or less and not having a (meth)acryloyl group. The content of the carboxylic acid or carboxylic anhydride (B) having a molecular weight of 500 or less and not having a (meth)acryloyl group is 3% by mass or less based on the total amount of the composition.

2. The radiation-curable composition according to claim 1, wherein the carboxylic acid or carboxylic anhydride (B) having a molecular weight of 500 or less and not having a (meth)acryloyl group has a cyclic hydrocarbon structure in the molecule.

3. The radiation-curable composition according to claim 1, wherein the carboxylic acid or carboxylic anhydride (B) having a molecular weight of 500 or less and not having a (meth)acryloyl group contains 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, rosin acid, dehydroabietic acid, and trimellitic anhydride.

4. The radiation-curable composition according to claim 1, which further contains a resin (C).

5. The radiation-curable composition according to claim 1, which further contains a colorant (D).

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

7. A laminate having a substrate and a layer formed of a cured product of the radiation-curable composition according to any one of claims 1 to 6.

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