Active energy ray curable inks and laminates

Abstract

The object of the present invention is to provide an active energy ray curable ink that has excellent adhesion and excellent curability, and a printed material that has high abrasion resistance, and a laminate using the ink. [Solution] An active energy ray curable ink containing a (meth)acrylate compound (a) having a weight-average molecular weight of less than 1000 and a (meth)acrylate compound (b) having a weight-average molecular weight of 1000 or more, wherein the (meth)acrylate compound (a) contains a (meth)acrylate compound having an isocyanurate ring.

Description

Technical Field

[0001] The present invention relates to an active energy ray-curable ink and a laminate using the ink.

Background Art

[0002] In recent years, active energy ray-curable inks can be cured by irradiating active energy rays such as ultraviolet rays, visible light rays, and electron beams in a very short time, have high productivity, and can obtain high coating film resistance, so they are widely used in fields where durability is required.

[0003] On the other hand, in printing, high-quality printed matter (laminates) is required, and accordingly, the types of substrates to be targeted have become diverse. For example, in order to impart physical properties that could not be achieved with conventional paper, such as polyolefin materials with high transparency from the viewpoint of beauty, and synthetic paper having a PET (polyethylene terephthalate) film substrate from the viewpoint of water resistance, the use of chemically synthesized materials as substrates has rapidly spread.

[0004] Conventional active energy ray-curable inks have the characteristic of instant curing by photopolymerization, but it has been difficult to achieve compatibility with the adhesion to substrates to be coated and printed, particularly olefin-based substrates such as polyethylene and polypropylene with low polarity. That is, as the instant curing property is pursued, volume shrinkage occurs in the cured film of the ink, or the flexibility of the film is impaired, resulting in a significant decrease in the adhesion to the substrate, and various studies have been conducted.

[0005] In Patent Document 1, as a method for expressing adhesion to an olefin-based resin film, an active energy ray-curable resin composition having adhesion containing rosin epoxy acrylate, a polyurethane resin having a carbon-carbon unsaturated group, and an acrylic compound is provided.

[0006] Furthermore, Patent Document 2 provides an active energy ray curable ink composition containing C5-C7 petroleum resins that exhibits adhesion and transferability to olefin resin films.

[0007] Furthermore, Patent Document 3 proposes an active energy ray curable ink composition that can be used in can applications and has excellent processability and blocking resistance, comprising a pigment, a polyester resin, an acrylate compound, and a photopolymerization initiator, wherein the acrylate compound includes an acrylate compound having an isocyanurate ring, a bifunctional acrylate, and a monofunctional acrylate.

[0008] In both methods, suppressing volume shrinkage (curing shrinkage) associated with the photopolymerization reaction is essential for achieving adhesion. As a result, the resulting ink film had a low degree of polymerization and insufficient abrasion resistance. [Prior art documents] [Patent Documents]

[0009] [Patent Document 1] Japanese Patent Application Publication No. 8-143635 [Patent Document 2] Japanese Patent Publication No. 2010-189537 [Patent Document 3] Patent No. 7319506 [Overview of the project] [Problems that the invention aims to solve]

[0010] The object of the present invention is to provide an active energy ray curable ink that has excellent adhesion and excellent curability, and a printed material that has high abrasion resistance, and a laminate using the ink. [Means for solving the problem]

[0011] The inventors of this invention have conducted extensive research to solve the above problems and have found that the above problems can be solved by the activated energy ray curing ink described below, thus completing the present invention.

[0012] In other words, embodiments of the present invention relate to the following. However, the present invention is not limited to the following embodiments and includes various embodiments. <1> An active energy ray curable ink containing (a) a (meth)acrylate compound having a weight-average molecular weight of less than 1000 and (b) a (meth)acrylate compound having a weight-average molecular weight of 1000 or more, An active energy ray curable ink in which the (meth)acrylate compound (a) comprises an (meth)acrylate compound (a1) having an isocyanurate ring.

[0013] <2> Furthermore, the above, including wax <1> The described active energy ray curing ink.

[0014] <3> The wax is polyethylene wax, as described above. <2> The described active energy ray curing ink.

[0015] <4> The viscosity of polyethylene wax at 25°C is 100 to 3,000 mPa·s, as stated above. <3> The described active energy ray curing ink.

[0016] <5> The mass ratio of (meth)acrylate compound (a) to (meth)acrylate compound (b) is such that (meth)acrylate compound (a):(meth)acrylate compound (b) = 50:50 to 95:5. <1> ~ <4> One of the active energy ray curing inks described below.

[0017] <6> The above is the case where the content of the (meth)acrylate compound having an isocyanurate ring is 5 to 70% by mass of the total amount of (meth)acrylate compound (a). <1> ~ <5> One of the active energy ray curing inks described below.

[0018] <7>The active energy ray-curable ink according to any one of <1> to <6> above, wherein the (meth)acrylate compound (b) contains one or more selected from the group consisting of epoxy (meth)acrylate, polyester (meth)acrylate, and urethane (meth)acrylate.

[0019] <8>The active energy ray-curable ink according to any one of <1> to <7> above, further containing a pigment.

[0020] <9>The active energy ray-curable ink according to any one of <1> to <8> above, which is for resin letterpress printing.

[0021] <10>A laminate having a layer of a cured product of the active energy ray-curable ink according to any one of <1> to <9> above on a substrate.

[0022] <11>The laminate according to <10> above, wherein the substrate is a paper substrate or a plastic film.

Advantages of the Invention

[0023] According to the present invention, it has been possible to provide an active energy ray-curable ink having excellent adhesion and excellent curability, and a laminate using the ink, and the laminate has high abrasion resistance.

Modes for Carrying Out the Invention

[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 are possible without departing from the gist of the present invention.

[0025] The terms used in this specification will be explained. "(Meth)acrylate" means acrylate and / or methacrylate, and "(meth)acryloyl group" means acryloyl group and / or methacryloyl group. Also, "PO" represents "propylene oxide" and "EO" represents "ethylene oxide".

[0026] <Activated energy ray curing ink> The active energy ray-curable ink of the present invention is an active energy ray-curable ink containing a (meth)acrylate compound (a) having a weight-average molecular weight (hereinafter also referred to as Mw) of less than 1000 and a (meth)acrylate compound (b) having a weight-average molecular weight of 1000 or more, wherein the (meth)acrylate compound (a) contains an (meth)acrylate compound (a) having an isocyanurate ring. By including a (meth)acrylate compound (a1) having an isocyanurate ring and a weight-average molecular weight of less than 1000, and a (meth)acrylate compound (b) having a weight-average molecular weight of 1000 or more, it is possible to achieve both excellent adhesion and excellent curability, which are often trade-off effects. As a result, the laminate can have high abrasion resistance.

[0027] The following describes the components included in, or potentially included in, the active energy ray curable ink of the present invention (hereinafter also simply referred to as "ink").

[0028] [(meth)acrylate compound (a)] The ink of the present invention contains a (meth)acrylate compound (a) having a weight-average molecular weight of less than 1000. The (meth)acrylate compound (a) is not particularly limited as long as it has a weight-average molecular weight of less than 1000 and contains one or more (meth)acryloyl groups in its molecule.

[0029] In this invention, the weight-average molecular weight (Mw) shall be determined by the value listed in the product catalog or other documentation used, or by the value measured by gel permeation chromatography (GPC) if no value is listed. Specifically, GPC measurements were performed using a gel permeation chromatography system (HLC-8320) manufactured by Tosoh Corporation. Calibration curves were prepared using standard polystyrene samples, tetrahydrofuran was used as the eluent, and three TSKgel SuperHM-M columns (manufactured by Tosoh Corporation) were used. Measurements were taken at a flow rate of 0.6 ml / min, an injection volume of 10 μl, and a column temperature of 40°C.

[0030] The ink of the present invention contains (meth)acrylate compound (a1) having an isocyanurate ring as (meth)acrylate compound (a).

[0031] Examples of (meth)acrylate compounds (a1) include isocyanuric acid EO-modified triacrylate, isocyanuric acid EO-modified diacrylate, and isocyanuric acid ε-caprolactone-modified triacrylate. (Meth)acrylate compounds (a1) may be used alone or in combination of two or more.

[0032] The content of (meth)acrylate compound (a1) is preferably 5 to 70% by mass, and more preferably 20 to 55% by mass, of the total amount of (meth)acrylate compound (a).

[0033] (Meth)acrylate compound (a) can be any (meth)acrylate compound (a2) other than (meth)acrylate compound (a1). Specifically, (meth)acrylate compounds (a2) include 2-ethylhexyl (meth)acrylate, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, β-carboxyethyl (meth)acrylate, 4-tert-butylcyclohexinol (meth)acrylate, tetrahydrofurfuryl acrylate, alkoxylated tetrahydrofurfuryl acrylate, caprolactone (meth)acrylate, lauryl (meth)acrylate, stearyl (meth)acrylate, isoamyl (meth)acrylate, 2-phenoxyethyl (meth)acrylate, and isodecyl (meth)acrylate. Monofunctional (meth)acrylate compounds having one (meth)acryloyl group in the molecule, such as 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 trimethylolpropaneformal (meth)acrylate, benzyl (meth)acrylate, EO-modified (2)nonylphenol acrylate, 2-methyl-2-ethyl-1,3-dioxolan-4-yl)methyl acrylate, acryloylmorpholine, and 2-(2-vinyloxyethoxy)ethyl acrylate. 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, Neopentyl glycol di(meth)acrylate hydroxypivalate , 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, cyclohexanedimethanol di(meth)acrylate, dimethylol-tricyclodecane di(meth)acrylate, dicyclopentanyl di(meth)acrylate, and other bifunctional (meth)acrylate compounds having two (meth)acryloyl groups in the molecule, Trifunctional (meth)acrylate compounds having three (meth)acryloyl groups in their molecule, such as trimethylolpropane tri(meth)acrylate, EO-modified (3) trimethylolpropane tri(meth)acrylate, EO-modified (6) trimethylolpropane tri(meth)acrylate, PO-modified (3) trimethylolpropane tri(meth)acrylate, and pentaerythritol tri(meth)acrylate. tetrafunctional (meth)acrylate compounds such as pentaerythritol tetra(meth)acrylate, ditrimethylolpropane tetra(meth)acrylate, EO-modified (4) pentaerythritol tetra(meth)acrylate, PO-modified (4) pentaerythritol tetra(meth)acrylate, EO-modified (4) ditrimethylolpropane tetra(meth)acrylate, and PO-modified (4) ditrimethylolpropane tetra(meth)acrylate. Pentafunctional (meth)acrylate compounds such as dipentaerythritol penta(meth)acrylate, EO-modified (5) dipentaerythritol penta(meth)acrylate, and PO-modified (5) dipentaerythritol penta(meth)acrylate. Examples include hexafunctional (meth)acrylate compounds such as dipentaerythritol hexa(meth)acrylate, EO-modified (6) dipentaerythritol hexa(meth)acrylate, and PO-modified (6) dipentaerythritol hexa(meth)acrylate. The (meth)acrylate compound (a2) may be used alone or in combination of two or more types.

[0034] The content of (meth)acrylate compound (a2) is preferably 10 to 80% by mass of the total amount of ink, and more preferably 30 to 70% by mass.

[0035] From the viewpoint of curability, the (meth)acrylate compound (a2) preferably contains a 2- to 6-functional (meth)acrylate compound.

[0036] [(meth)acrylate compound (b)] The ink in this invention contains a (meth)acrylate compound (b) having a weight-average molecular weight of 1000 or more. The (meth)acrylate compound (b) is not particularly limited as long as it has a weight-average molecular weight of 1000 or more and contains one or more (meth)acryloyl groups in its molecule. From the viewpoint of maintaining curability by increasing the crosslinking density using the (meth)acrylate compound, the weight-average molecular weight of the (meth)acrylate compound (b) is preferably 1000 to 6000.

[0037] As the (meth)acrylate compound (b), urethane (meth)acrylate, polyester (meth)acrylate, epoxy (meth)acrylate, etc. can be used.

[0038] Examples of urethane (meth)acrylates include those obtained by reacting diisocyanate with (meth)acrylates having hydroxyl groups, and those obtained by reacting an isocyanate group-containing urethane prepolymer, which is obtained by reacting a polyol with polyisocyanate under conditions of excess isocyanate groups, with (meth)acrylates having hydroxyl groups. Alternatively, a hydroxyl group-containing urethane prepolymer, which is obtained by reacting a polyol with polyisocyanate under conditions of excess hydroxyl groups, can also be obtained by reacting an isocyanate group-containing (meth)acrylate.

[0039] Commercially available products that can be used as urethane (meth)acrylate include: Daicel Ornex's "EBECRYL 220", "EBECRYL 225", "EBECRYL 230", "EBECRYL 270", "EBECRYL 284", "EBECRYL 280 / 15IB", "EBECRYL 8307", "EBECRYL 8402", "EBECRYL 8804", "EBECRYL 9270", "EBECRYL 4820", "EBECRYL 9260", and "EBECRYL 210"; Arakawa Chemical Industries, Ltd.'s "Beamset 550B"; and Miwon Specialty Chemical's "Miramer UA5216", "Miramer SC2404", "Miramer SC2565", "Miramer PU210", "Miramer PU256", "Miramer PU2050", and "Miramer". Examples include the "PU2100," "Miramer PU2300C," "Miramer PU2560," "Miramer PU320," "Miramer PU340," "Miramer PU3200," and "Miramer PU3450."

[0040] Polyester (meth)acrylates can be obtained, for example, by reacting a polyester polycarboxylic acid, which is obtained by polycondensation of a polybasic acid and a polyhydric alcohol, with a hydroxyl group-containing (meth)acrylate.

[0041] Commercially available polyester (meth)acrylate compounds that can be used include "EBECRYL 80", "EBECRYL 83", "EBECRYL L436", "EBECRYL 810", "EBECRYL 1830", "EBECRYL 1846", "EBECRYL 1870", "EBECRYL 884", and "EBECRYL 885" from Daicel Ornex, and "ETERCURE63571", "ETERCURE63575H", "ETERCURE63578", "ETERCURE63595", "ETERCURE635961", "ETERCURE63597", and "ETERCURE63161" from Choko Materials Industry Co., Ltd.

[0042] It is preferable to use rosin-modified polyester (meth)acrylate as the polyester (meth)acrylate. Using rosin-modified polyester (meth)acrylate allows for good wettability to the pigment and good dispersion, resulting in good hue development.

[0043] Rosin-modified polyester (meth)acrylate compounds include, but are not limited to, those obtained by reacting a rosin-modified polyester compound, which is produced by a Diels-Alder addition reaction between a conjugated rosinic acid and an ethylenically unsaturated double bond-containing compound having a carboxyl group, and further by an esterification reaction between the carboxyl group of the reaction compound and the hydroxyl group of a polyol, with a hydroxyl-containing (meth)acrylate compound.

[0044] Commercially available products that can be used as rosin-modified polyester (meth)acrylate include "ETERCURE63571", "ETERCURE63575H", "ETERCURE63578", "ETERCURE63595", "ETERCURE635961", "ETERCURE63597", and "ETERCURE63161" manufactured by Choko Materials Industry Co., Ltd.

[0045] Epoxy (meth)acrylates are obtained by esterifying the glycidyl group of an epoxy resin with (meth)acrylic acid, resulting in a functional group of (meth)acrylate group. Examples include (meth)acrylic acid adducts to bisphenol A type epoxy resins and (meth)acrylic acid adducts to novolac type epoxy resins.

[0046] Commercially available epoxy (meth)acrylate products that can be used include "EBECRYL 860" and "EBECRYL 3708" from Daicel Ornex, "Miramer PE310" and "Miramer EA2280" from Miwon Specialty Chemical, and "PHOTOMER3005" from IGM Resins.

[0047] It is preferable to use vegetable oil-modified epoxy acrylate as the epoxy (meth)acrylate. By using vegetable oil-modified epoxy acrylate, good wettability to the pigment and good dispersion can be obtained, resulting in good hue development.

[0048] Vegetable oil-modified epoxy acrylates can be any known compounds, such as those obtained by adding acrylic acid to the epoxy group of an epoxidized vegetable oil, which is formed by epoxidizing the double bonds of an unsaturated vegetable oil with peracetic acid or perbenzoic acid. Preferred vegetable oils to be modified include soybean oil, rapeseed oil, sunflower oil, and corn oil.

[0049] Commercially available vegetable oil-modified epoxy acrylates that can be used include "EBECRYL 860" from Daicel Ornex, "Miramer PE310" from Miwon Specialty Chemical, and "PHOTOMER3005" from IGM Resins.

[0050] In the ink of the present invention, the (meth)acrylate compound (b) may be used alone or in combination of two or more types.

[0051] In the ink of the present invention, it is preferable that the mass ratio of (meth)acrylate compound (a) to (meth)acrylate compound (b) is (meth)acrylate compound (a):(meth)acrylate compound (b) = 50:50 to 95:5. A mass ratio of 50:50 to 95:5 between (meth)acrylate compound (a) and (meth)acrylate compound (b) results in an appropriate ink viscosity and good printability.

[0052] [Non-reactive resin] The ink of the present invention may contain a non-reactive resin that does not have (meth)acryloyl groups in its molecule. By including a non-reactive resin, it is possible to ensure appropriate ink viscosity and fluidity, resulting in good printability.

[0053] As non-reactive resins, those having excellent compatibility with (meth)acrylate compound (a) are preferred, and examples include diallyl phthalate resin, non-phthalate allyl resin, rosin-modified resin, polyvinyl chloride, poly(meth)acrylic acid ester, epoxy resin, polyester resin, styrene acrylic resin, polyurethane resin, cellulose derivative (e.g., ethylcellulose, cellulose acetate, nitrocellulose), vinyl chloride-vinyl acetate copolymer, polyamide resin, polyvinyl acetal resin, petroleum resin, alkyd resin, urea resin, and synthetic rubber such as butadiene-acrylonitrile copolymer.

[0054] [Pigments] The ink of the present invention may contain pigments. The pigments in the present invention include colored pigments as colorants and extender pigments. If colored pigments are not included, it becomes a clear ink (also called varnish).

[0055] There are no particular restrictions on the colored pigments that can be used in the present invention; any known colored pigments can be used. Both inorganic and organic colored pigments can be used.

[0056] Examples of inorganic pigments include carbon blacks such as furnace black, lamp black, acetylene black, and channel black, as well as iron oxide and titanium dioxide.

[0057] Organic pigments include soluble azo pigments such as β-naphthol-based, β-oxynaphthoic acid-based, β-oxynaphthoic acid-based anilide-based, acetoacetate anilide-based, and pyrazolone-based; insoluble azo pigments such as β-naphthol-based, β-oxynaphthoic acid-based anilide-based, acetoacetate anilide-based monoazo, acetoacetate anilide-based disazo, and pyrazolone-based; copper phthalocyanine blue, halogenated (e.g., chlorinated or brominated) copper phthalocyanine blue, and sulfo Examples include phthalocyanine pigments such as copper phthalocyanine blue and metal-free phthalocyanines; polycyclic and heterocyclic pigments such as quinacridone, dioxazine, slene (pyrantrone, anthantrone, indanthrone, anthrapyrimidine, flavanthrone, thioindigo, anthraquinone, perinone, perylene, etc.), isoindolinone, metal complex, quinophthalone, and diketopyrrolopyrrole.

[0058] More specifically, using the CI color index, examples of black pigments include CIPigment Black 1, 6, 7, 9, 10, 11, 28, 26, and 31.

[0059] Examples of white pigments include CIPigment White 5, 6, 7, 12, and 28.

[0060] Examples of yellow pigments include CIPigment 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.

[0061] Examples of blue or cyan pigments include CIPigment Blue 1, 2, 14, 15, 15:1, 15:2, 15:3, 15:4, 60, and 62.

[0062] As red or crimson pigments, CIPigment 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 Examples include 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, and CIPigment Violet 19.

[0063] Examples of green pigments include CIPigment Green 1, 2, 3, 4, 7, 8, 10, 15, 17, 26, 36, 45, and 50.

[0064] Examples of purple pigments include CIPigment Violet 1, 2, 3, 4, 5:1, 12, 13, 15, 16, 17, 19, 23, 25, 29, 31, 32, 36, 37, 39, and 42.

[0065] Examples of orange pigments include CIPigment Orange 13, 16, 20, 34, 36, 38, 39, 43, 51, 61, 63, 64, and 74.

[0066] In the present invention, the above-mentioned colored pigment may be used alone or in combination of two or more types.

[0067] In the present invention, the above-mentioned colored pigment can be used in any amount as long as the desired concentration can be reproduced, and is preferably 5 to 60% by mass of the total mass of the composition.

[0068] There are no particular restrictions on the extender pigments that can be used in the present invention; known extender pigments can be used. 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, and polishing powder, as well as silicone and glass beads. 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. The above extender pigments may be used individually or in combination of two or more types.

[0069] In the present invention, the content of the extender pigment is preferably 1 to 10% by mass, based on the total mass of the ink.

[0070] [Photopolymerization initiator] The ink 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 interaction with the electronically excited state of a sensitizing dye, and among these, a photoradical polymerization initiator is preferred from the viewpoint that polymerization can be initiated by exposure.

[0071] It is preferable to use one or more photopolymerization initiators selected from the group consisting of α-aminoalkylphenone initiators, thioxanthone initiators, benzophenone initiators, dialkoxyacetophenone initiators, α-hydroxyalkylphenone initiators, and acylphosphine oxide initiators.

[0072] Examples of α-aminoalkylphenone initiators include 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-butanone-1, 2-dimethylamino-2-(4-methyl-benzyl)-1-(4-morpholin-4-yl-phenyl)-butan-1-one, 2-benzyl-2-dimethylamino-1-(4-piperidinophenyl)-butan-1-one, 1-[4-(butylsulfanyl)phenyl]-2-methyl-2-(morpholin-4-yl)propan-1-one, 1,2-octanedione, 1-[4-(phenylthio)-,2-(O-benzoyloxime)], ethanone, 1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazole-3-yl]-,1-(O-acetyloxime), and 3,6-bis(2-methyl-2-morpholinopropanonyl) Examples include )-9-butylcarbazole, 2-methyl-1-[4-(methylthio)phenyl]-2-morpholinopropan-1-one, 2-hydroxy-1-{4-[4-(2-hydroxy-2-methylpropionyl)-benzyl]-phenyl}-2-methyl-propan-1-one, 2,2-dimethoxy-1,2-diphenylethane-1-one, 2,2-diethoxy-1,2-diphenylethane-1-one, etc., which may be used alone or in combination of two or more.

[0073] Examples of thioxanthone-based initiators include 2,4-diethylthioxanthone, 2,4-dimethylthioxanthone, 2,4-diisopropylthioxanthone, 2-isopropylthioxanthone, 4-isopropylthioxanthone, 2,4-dichlorothioxanthone, α-[(4-benzoylphenoxy)acetyl]-ω-{[(4-benzoylphenoxy)acetyl]oxy}poly(oxybutane-1,4-diyl), 2-chlorothioxanthone, 1-chloro-4-propoxythioxanthone, and 2-hydroxy-3-(3,4-dimethyl-9-oxo-9Hthioxanthone-2-yloxy-N,N,N-trimethyl-1-propanamine hydrochloride).

[0074] Examples of benzophenone-based initiators include benzophenone, 4-methylbenzophenone, 4-phenylbenzophenone, 4,4'-bis(diethylamino)benzophenone, 4,4'-bis(dimethylamino)benzophenone, and [4-(methylphenylthio)phenyl]phenylmethanone.

[0075] Examples of dialkoxyacetophenone initiators include 2,2-dimethoxy-2-phenylacetophenone, dimethoxyacetophenone, and diethoxyacetophenone.

[0076] Examples of α-hydroxyalkylphenone initiators include 1-hydroxycyclohexylphenyl ketone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 1-[4-(2-hydroxymethoxy)-phenyl]-2-hydroxy-2-methyl-1-propan-1-one, 2-hydroxy-1-{4-[4-(2-hydroxy-2-methylpropionyl)-benzyl]phenyl}-2-methylpropan-1-one, and 2-benzyl-2-dimethylamino-1-(4-piperidinophenyl)-butan-1-one.

[0077] Examples of acylphosphine oxide initiators include 2,4,6-trimethylbenzoyl-diphenylphosphine oxide, bis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide, 2,4,6-trimethylbenzoyl-bis(4-methylphenyl)phosphinyl oxide, and ethoxyphenyl(2,4,6-trimethylbenzoyl)phosphine oxide.

[0078] To ensure sufficient curability, the amount of photopolymerization initiator added is preferably 2 to 15% by mass of the total ink mass. More preferably, it is 3 to 12% by mass of the total ink mass.

[0079] When ultraviolet light is used as the active energy ray for curing the ink of the present invention, a photosensitizer can also be used in combination to further improve curability. 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.

[0080] [Photopolymerization inhibitor] The ink in this invention may contain a photopolymerization inhibitor. The inclusion of a photopolymerization inhibitor allows for excellent storage stability.

[0081] Examples of photopolymerization inhibitors, from the viewpoint of storage stability, include nitroso compounds, phenolic compounds, quinone compounds, and piperidine compounds.

[0082] Examples of nitroso compounds include nitrosobenzene, aluminum N-nitrosophenylhydroxylamine, tri-p-nitrophenylmethyl, picric acid, cuperone, butyraldoxime, methyl ethyl ketoxime, and cyclohexanone oxime.

[0083] Examples of phenolic compounds include (alkyl)phenol, p-methoxyphenol, o-isopropylphenol, catechol, resorcinol, t-butylcatechol, pyrogallol, dibutylcresol, and guaiacol.

[0084] Examples of quinone compounds include hydroquinone, t-butylhydroquinone, p-benzoquinone, and 2,5-di-tert-butyl-p-benzoquinone.

[0085] Examples of piperidine compounds include phenothiazines.

[0086] Furthermore, it is also possible to use photopolymerization inhibitors other than the nitroso compounds, phenol compounds, quinone compounds, and piperidine compounds mentioned above (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.

[0087] The amount of photopolymerization inhibitor added is preferably 0.01 to 5% by mass of the total ink amount.

[0088] [wax] The ink of the present invention may contain a wax. By adding a wax, high abrasion resistance can be maintained. The wax may include one or more selected from the group consisting of polyolefin wax, paraffin wax, acrylic beeswax, urethane beeswax, Fischer-Tropsch wax, microcrystalline wax, petrolatum, polytetrafluoroethylene wax, and carnauba wax. These waxes may be used individually or in combination. Examples of polyolefin waxes include polyethylene wax, polypropylene wax, ethylene-propylene copolymer wax, and oxidized polyethylene wax. Among these, polyethylene wax is preferable because it provides particularly high abrasion resistance.

[0089] While the addition of wax to ink can sometimes worsen adhesion and curability depending on the ink's composition, the ink of the present invention contains a (meth)acrylate compound (a1) having an isocyanurate ring and a weight-average molecular weight of less than 1000, a (meth)acrylate compound (b) having a weight-average molecular weight of 1000 or more, and wax. This allows for improved abrasion resistance of the resulting laminate without compromising excellent adhesion and curability.

[0090] As for the polyethylene wax, a liquid polyethylene wax with a viscosity of 100 to 3000 mPa·s at 25°C is more preferable. Being liquid makes it easier to expose to the ink surface, which is also good from the viewpoint of abrasion resistance.

[0091] The aforementioned liquid polyethylene wax can be any known product. Specifically, examples include Versaflow LV, Versaflow BASE, Versaflow EV, and Versaflow HV manufactured by SHAMROCK.

[0092] In this invention, the wax may be used alone or in combination of two or more types.

[0093] Furthermore, in the present invention, it is preferable to use liquid polyethylene wax and a wax that is solid at 25°C in combination, as this provides sustained abrasion resistance.

[0094] Furthermore, in the present invention, the wax used in combination with liquid polyethylene wax is preferably polyethylene wax, acrylic beeswax, or polytetrafluoroethylene wax, and more preferably polyethylene wax, polytetrafluoroethylene wax, and / or acrylic beeswax are used in combination. Polyethylene wax, which is solid at 25°C, has an irregular shape, and by using it in combination with polytetrafluoroethylene wax or acrylic beeswax, which have a granular shape, the abrasion resistance is improved.

[0095] The wax content is preferably 0.5 to 10% by mass of the total amount of the active energy ray curable composition. When the wax content is 0.5 to 10% by mass of the total amount of the composition, both abrasion resistance and gloss and printability are good. More preferably, the wax content is 1 to 5% by mass of the total amount of the composition.

[0096] [Additives] The ink in this invention may further contain various additives, such as pigment dispersants, anti-blocking agents, and lubricants, depending on the purpose. These additives can be added to the composition by conventional methods. When adding various additives, it is preferable to adjust the amount so as not to interfere with the effects of other materials. The amount of each additive is preferably 15% by mass or less of the total amount of ink.

[0097] <Laminate> The laminate of the present invention is obtained by printing the ink of the present invention onto a substrate and curing it with active energy rays.

[0098] Examples of substrates used in the laminate of the present invention include paper substrates such as coated paper such as art paper, coated paper, and cast paper; synthetic paper such as Yupo paper; and plastic films such as PET (polyethylene terephthalate), PP (polypropylene), and OPP (biaxially oriented polypropylene). Since the ink of the present invention exhibits excellent adhesion to plastic films in particular, plastic films are preferred as the substrate.

[0099] Methods for printing the ink of the present invention onto a substrate include resin letterpress printing without dampening solution, dry offset printing, and flexographic printing. Among these, resin relief printing is preferred over ink viscosity according to the present invention.

[0100] Active energy rays typically include ionizing radiation such as ultraviolet rays, electron beams, X-rays, alpha rays, beta rays, and gamma rays, as well as microwaves and radio waves. However, any energy species that can generate radical active species is acceptable, including visible light, infrared rays, and laser light. Examples of devices that generate ultraviolet light 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. In particular, the use of LEDs, high pressure mercury lamps, and metal halide lamps is preferred in the present invention.

[0101] The laminate of the present invention can be suitably used for printed materials for seals / labels, art prints, and the like. [Examples]

[0102] 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 this specification, "parts" refers to parts by mass, and "%" refers to mass percent.

[0103] [Manufacturing of active energy ray curing inks] Example 1 16.0 parts of MIRAMER M370 as a (meth)acrylate compound having an isocyanurate ring, and 16.3 parts of MIRAMER M320 as a (meth)acrylate compound with a weight-average molecular weight of less than 1000, MIRAMER 4.0 parts of M220, 35 parts of ETECURE63575H, a mixture of rosin-modified polyester acrylate (b), which is a (meth)acrylate compound (b) with a weight-average molecular weight of 1000 or more, and trimethylolpropane EO-modified triacrylate (a), which is a (meth)acrylate compound (a) with a weight-average molecular weight of less than 1000, 2.0 parts of Gantzpearl GM0105 as acrylic beeswax, 1.3 parts of Sunwax 161P as polyethylene wax, 0.5 parts of Versaflow LV as liquid polyethylene wax, 12.3 parts of blue pigment as a colored pigment, 1.0 part of Highfilar Talc 5000PJ as an extender pigment, 5.0 parts of OMNIRAD389 and 2.0 parts of OMNIRAD DETX as photopolymerization initiators. 4.0 parts of rosin-modified resin as a non-reactive resin, 0.5 parts of Adisper PB821 as an additive (pigment dispersant), and 0.1 parts of Q-1301 as a photopolymerization inhibitor were added. The mixture was stirred and mixed using a mixer, and dispersion was carried out using a three-roll roller to prepare the ink of Example 1.

[0104] Examples 2-24, Comparative Examples 1-2 Except for changing the raw materials and quantities listed in Table 1, the inks of Examples 2-24 and Comparative Examples 1-2 were obtained using the same method as in Example 1. Note that unless otherwise specified, the values ​​in the table represent "parts by mass," and blank spaces indicate that an ingredient was not included.

[0105] [Table 1]

[0106] [Table 1]

[0107] The manufacturing process for the above-mentioned active energy ray-curable ink, and the abbreviations in Table 1, are as follows: [(meth)acrylate compounds (a) with a weight-average molecular weight (Mw) of less than 1000] (a1) (meth)acrylate compound having an isocyanurate ring • MIRAMER M370: Manufactured by Bigen Specialty Chemicals Co., Ltd., isocyanuric acid EO modified triacrylate, Mw423 • Arronix M-215: Manufactured by Toagosei Co., Ltd., isocyanuric acid EO-modified diacrylate, Mw369 (a1) Other (meth)acrylate compounds (a2) • MIRAMER LR3130: Manufactured by Bigen Specialty Chemicals Co., Ltd., Trimethylolpropane EO-modified triacrylate, Mw428 • MIRAMER M320: Manufactured by Bigen Specialty Chemicals Co., Ltd., Glycerin Propoxy Triacrylate, Mw428, • MIRAMER M220: Manufactured by Bigen Specialty Chemicals Co., Ltd., Tripropylene glycol diacrylate, Mw300 • MIRAMER M2010: Manufactured by Bigen Specialty Chemicals Co., Ltd., 1,10-decanediol diacrylate, Mw282 • MIRAMER M410: Manufactured by Bigen Specialty Chemicals Co., Ltd., ditrimethylolpropanetetraacrylate, Mw466 • MIRAMER M142: Manufactured by Bigen Specialty Chemicals Co., Ltd., phenoxydiethylene glycol acrylate, Mw236 • MIRAMER M600: Manufactured by Bigen Specialty Chemicals Co., Ltd., contains dipentaerythritol hexaacrylate, Mw578 Trimethylolpropane EO-modified triacrylate: Trimethylolpropane EO-modified triacrylate (50% by mass) in ETECURE63575H manufactured by Choko Materials Industry Co., Ltd., Mw428 [(meth)acrylate compounds (b) with a weight-average molecular weight of 1000 or more] • Rosin-modified polyether acrylate: Rosin-modified polyether acrylate (50% by mass) in ETECURE63575H manufactured by Choko Material Industry Co., Ltd., Mw2500 • MIRAMER PE310: Manufactured by Bigen Specialty Chemicals Co., Ltd., soybean oil modified epoxy acrylate, Mw2200 • EBECRYL225: Manufactured by Daicel Ornex, urethane acrylate, Mw1200 • MIRAMER SC2565: Manufactured by Bigen Specialty Chemicals Co., Ltd., Urethane acrylate, Mw5200 [Non-reactive resin] • Rosin-modified resin: Using resin 4 (Mw23000) described in paragraph 0076 of International Publication No. 2017 / 164246. [Pigments (colored pigments)] LionolBlue FG7330, manufactured by Toyo Color Co., Ltd., indigo pigment. • Typeque CR-60-2, manufactured by Ishihara Sangyo Co., Ltd., white pigment [Pigments (extender pigments)] • High Filler 5000PJ: Manufactured by Matsumura Sangyo Co., Ltd.: Talc [wax] • Sanwax 161P: Manufactured by Sanyo Chemical Industries. Polyethylene wax (solids at 25°C) Versaflow LV: Liquid polyethylene wax, 100 mPa·s (25℃) Versaflow EV: Liquid polyethylene wax, 1000 mPa·s (25℃) • SST-3T1-RC: Made by Shamrocks, polytetrafluoroethylene wax • Gantzpearl GM0105: Manufactured by Gantz Chemicals, acrylic beeswax [Photopolymerization initiator] • Omnirad 389: Manufactured by IGM, α-aminoalkylphenone initiator, 2-benzyl-2-dimethylamino-1-(4-piperidinophenyl)-butan-1-one • Omnirad DETX: Manufactured by IGM, a thioxanthone initiator, 2,4-diethylthioxanthone • OmniradTPOL: Ethoxyphenyl (2,4,6-trimethylbenzoyl)phosphine oxide [Polymerization inhibitor] • Q-1301: Manufactured by Fujifilm Wako Pure Chemical Industries, Ltd., a nitroso compound, N-nitrosophenylhydroxylamine aluminum salt. [Additives (Pigment Dispersants)] • Azisper PB821: Pigment dispersant manufactured by Ajinomoto Fine Techno Co., Ltd.

[0108] The adhesion, curability, and abrasion resistance of the inks obtained in the examples and comparative examples were evaluated using the following method. The results are shown in Table 2.

[0109] <How to prepare test samples> The obtained ink was used to print a solid image onto the substrate, PET50(A)PAT18LK (Lintec), with a load of 0.25 ml using an RI tester (manufactured by Tester Industry Co., Ltd.). The ink was then cured using an LED lamp (Air Motion System Co., Ltd. "XP-9", irradiation distance 10 mm, output 70%) at a conveyor speed of 100 m / min to create a test sample. The RI tester is a testing machine used to print ink onto paper and film, and allows for adjustment of ink transfer amount and printing pressure.

[0110] <Adhesion> For each ink in Examples 1-24 and Comparative Examples 1-2, adhesive tape (Nichiban Cellotape®, 18mm wide) was applied to the cured ink layer of the test sample prepared using the method described above, and peeling was performed in a vertical direction. The adhesion to the substrate was evaluated from the percentage of the area where the ink film was peeled off. ◎, ○, and △ indicate a level that is acceptable for practical use, and preferably ◎ and ○ are considered to be even better. ◎: No peeling of the ink coating. ○: Less than 10% of the ink coating is peeled off. △: Ink coating peeling is between 10% and 50%. ×: More than 50% of the ink coating peels off.

[0111] <Abrasion resistance> For each ink in Examples 1-24 and Comparative Examples 1-2, abrasion resistance tests were performed on the cured ink layer of the test samples prepared using the method described above, using a JSPS-type friction fastness tester manufactured by Tester Sangyo Co., Ltd. (load 500g, 200 cycles, paper: high-quality paper). The scratches that occurred in the cured ink layer were evaluated. ◎, ○, and △ indicate a level that is not problematic for practical use, and preferably ◎ and ○ are considered to be even better levels. ◎: No scratches at all ○: The wound covers less than 10% of the area. △: The wound covers 10% or more but less than 50% of the total area. ×: The wound covers more than 50% of the area.

[0112] <Curability> The obtained ink was used to create a colored material (substrate: PET50(A)PAT18LK (Lintec)) using a 4-part roll RI tester (manufactured by Tester Industry Co., Ltd.) with an ink volume of 0.075 ml. The ink was then cured using an LED lamp (Air Motion System Co., Ltd. "XP-9", irradiation distance 30 mm, output 70%) at a conveyor speed of 100 m / min. The surface of the cured ink was evaluated by rubbing it with a cotton cloth. Less rubbing indicates better curability. The evaluation criteria are as shown below, with ◎, ○, and △ indicating a level that is acceptable for practical use, and preferably ◎ and ○ indicating an even better level. ◎: No rubbing of hardened ink onto the surface. ○: Can be rubbed down to the surface layer of the hardened ink. △: Can be rubbed up to the middle of the surface of the hardened ink. ×: The ink can be rubbed down to the bottom surface of the hardened material.

[0113] [Table 2]

[0114] As shown in Table 2, the adhesion, curability, and abrasion resistance of Examples 1 to 24 were within practical limits. On the other hand, Comparative Example 1 does not contain an isocyanurate ring-containing (meth)acrylate compound (a1), and therefore does not exhibit adhesion. Comparative Example 2 does not contain an isocyanurate ring-containing (meth)acrylate compound or (meth)acrylate compound (b), and therefore does not reach a practical level in terms of adhesion, curability, and abrasion resistance.

[0115] Based on the above, the present invention provides an active energy ray curable ink that offers a laminate with excellent adhesion, curability, and abrasion resistance.

Claims

1. An active energy ray curable ink containing (a) a (meth)acrylate compound having a weight-average molecular weight of less than 1000 and (b) a (meth)acrylate compound having a weight-average molecular weight of 1000 or more, The (meth)acrylate compound (a) is an active energy ray curable ink comprising an (meth)acrylate compound (a1) having an isocyanurate ring.

2. Furthermore, the active energy ray curable ink according to claim 1, further comprising wax.

3. The active energy ray curable ink according to claim 2, wherein the wax is polyethylene wax.

4. The active energy ray curable ink according to claim 3, wherein the viscosity of the polyethylene wax at 25°C is 100 to 3,000 mPa·s.

5. The active energy ray curable ink according to claim 1, wherein the mass ratio of (meth)acrylate compound (a) to (meth)acrylate compound (b) is (meth)acrylate compound (a):(meth)acrylate compound (b) = 50:50 to 95:

5.

6. The active energy ray curable ink according to claim 1, wherein the content of the (meth)acrylate compound (a1) having an isocyanurate ring is 5 to 70% by mass of the total amount of the (meth)acrylate compound (a).

7. The active energy ray curable ink according to claim 1, wherein the (meth)acrylate compound (b) comprises one or more selected from the group consisting of epoxy (meth)acrylate, polyester (meth)acrylate, and urethane (meth)acrylate.

8. Furthermore, the active energy ray curable ink according to claim 1, further comprising a pigment.

9. The active energy ray curable ink according to claim 1, for use in resin relief printing.

10. A laminate having a layer of cured product of an active energy ray curable ink according to any one of claims 1 to 9 on a substrate.

11. The laminate according to claim 10, wherein the base material is a paper base material or a plastic film.

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