Active energy ray-curable coating composition

Abstract

To provide an active energy ray-curable coating composition which has a small environmental load, exhibits excellent adhesiveness and can impart excellent glossiness when applied to a printed matter (especially a printed matter printed by an electrophotographic system).SOLUTION: There is provided an active energy ray-curable coating composition having viscosity at 25°C of 40 to 380 mPa s, which comprises a resin, an ethylenically unsaturated compound, an initiator and a polymerization inhibitor, wherein the resin includes an amine-modified styrene (meth)acrylic resin, the content of the amine-modified styrene (meth)acrylic resin is 5 to 30 mass%, the ethylenically unsaturated compound includes at least one of acryloyl morpholine and vinylcaprolactam, the total of the content of at least one of acryloyl morpholine and vinylcaprolactam is 41 mass% or more, the polymerization inhibitor contains a piperidine derivative and the content of the piperidine derivative is 0.05 to 1 mass%.SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to an active energy ray-curable coating composition. More specifically, the present invention relates to an active energy ray-curable coating composition that, when applied to a printed matter (particularly a printed matter printed by an electrophotographic method), exerts a small load on the environment, exhibits excellent adhesion, and can impart excellent glossiness. [Background technology]

[0002] Conventionally, printed matter printed by electrophotography is subjected to lamination processing to protect the printed surface and to impart beauty. In response to this, active energy ray-curable overprint varnishes have been developed to reduce costs and impart further beauty (Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 3246671 Summary of the Invention [Problem to be solved by the invention]

[0004] However, the varnish described in Patent Document 1 had problems in that it did not have sufficient adhesion when applied to printed matter (especially printed matter printed by an electrophotographic method) and was unable to impart sufficient gloss.

[0005] The present invention has been made in consideration of the above circumstances, and an object of the present invention is to provide an active energy ray-curable coating composition which, when applied to printed matter (particularly printed matter printed by an electrophotographic method), imparts little environmental load, exhibits excellent adhesion, and can impart excellent gloss. [Means for solving the problem]

[0006] The active energy ray-curable coating composition of the present invention that solves the above problems mainly comprises the following components.

[0007] (1) An active energy ray-curable coating composition comprising a resin, an ethylenically unsaturated compound, an initiator, and a polymerization inhibitor, wherein the resin comprises an amine-modified styrene (meth)acrylic resin, the content of the amine-modified styrene (meth)acrylic resin being 5 to 30 mass %, the ethylenically unsaturated compound comprises at least one of acryloylmorpholine and vinylcaprolactam, the total content of at least one of the acryloylmorpholine and the vinylcaprolactam being 41 mass % or more, the polymerization inhibitor comprises a piperidine derivative, the content of the piperidine derivative being 0.05 to 1 mass %, and the viscosity at 25°C being 40 to 380 mPa s.

[0008] According to such a configuration, the active energy ray-curable coating composition, when applied to a printed matter (particularly a printed matter printed by an electrophotographic method), can impart a small load to the environment, exhibit excellent adhesion, and impart excellent glossiness.

[0009] (2) The active energy ray-curable coating composition according to (1), wherein the content of the amine-modified styrene (meth)acrylic resin is 15 to 25 mass %.

[0010] According to such a configuration, the active energy ray-curable coating composition exhibits better adhesion and can impart better gloss when applied to a printed matter (particularly a printed matter printed by an electrophotographic method).

[0011] (3) The active energy ray-curable coating composition according to (1) or (2), which has a viscosity at 25° C. of 40 to 299 mPa·s.

[0012] According to this configuration, the active energy ray-curable coating composition has excellent leveling properties and is easy to apply.

[0013] (4) The active energy ray-curable coating composition according to any one of (1) to (3), which is applied to a printed matter printed by an electrophotographic method.

[0014] According to such a configuration, the active energy ray-curable coating composition, when applied to an electrophotographically printed matter, imparts little environmental load, exhibits excellent adhesion, and can impart excellent gloss.

[0015] (5) A coated printed material, in which the active energy ray-curable coating composition according to any one of (1) to (4) is applied to a printed material printed by an electrophotographic method.

[0016] According to this configuration, the coated printed matter exhibits excellent adhesion and excellent gloss. Effect of the Invention

[0017] According to the present invention, it is possible to provide an active energy ray-curable coating composition which, when applied to a printed matter (particularly a printed matter printed by an electrophotographic method), imparts a small load to the environment, exhibits excellent adhesion, and can impart excellent glossiness. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0018] <Active energy ray curable coating composition> An active energy ray curable coating composition (hereinafter also referred to as coating composition) according to one embodiment of the present invention contains a resin, an ethylenically unsaturated compound, an initiator, and a polymerization inhibitor. The resin contains an amine-modified styrene (meth)acrylic resin. The content of the amine-modified styrene (meth)acrylic resin is 5 to 30 mass %. The ethylenically unsaturated compound contains at least one of acryloylmorpholine and vinylcaprolactam. The total content of at least one of acryloylmorpholine and vinylcaprolactam is 41 mass % or more. The polymerization inhibitor contains a piperidine derivative. The content of the piperidine derivative is 0.05 to 1 mass %. The viscosity at 25°C is 40 to 380 mPa·s. Each of these will be described below.

[0019] (resin) The resin includes an amine-modified styrene (meth)acrylic resin. As long as the amine-modified styrene (meth)acrylic resin is a styrene (meth)acrylic resin having an amino group, any resin obtained by a known technique can be used. Specifically, the amine-modified styrene (meth)acrylic resin is an α,β-unsaturated double bond group-containing compound having an amino group, a copolymer of a styrene-based compound and an α,β-unsaturated double bond group-containing compound (excluding styrene-based compounds), a styrene-acrylic copolymer having a carboxylic acid group reacted with ethyleneimine (aminoethylation), and the like. Among these, the amine-modified styrene (meth)acrylic resin is preferably an α,β-unsaturated double bond group-containing compound having an amino group, a copolymer of a styrene-based compound and an α,β-unsaturated double bond group-containing compound (excluding styrene-based compounds).

[0020] Examples of the α,β-unsaturated double bond group-containing compound having an amino group include acrylic acid esters such as N,N-dimethylaminoethyl (meth)acrylate, N,N-diethylaminoethyl (meth)acrylate, and N,N-dimethylaminopropyl (meth)acrylate, and acrylamides such as N,N-dimethylaminoethyl (meth)acrylamide, N,N-dimethylaminoethyl (meth)acrylamide, and N,N-dimethylaminopropyl (meth)acrylamide.

[0021] The styrene-based compounds include styrene, α-methylstyrene, and vinylstyrene.

[0022] The α,β-unsaturated double bond group-containing compound is not particularly limited as long as it is other than the acrylic acid ester and styrene monomer having the above-mentioned amino group. For example, the α,β-unsaturated double bond group-containing compound is methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, isopropyl (meth)acrylate, butyl (meth)acrylate, isobutyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, cyclohexyl (meth)acrylate, etc.

[0023] The weight average molecular weight of the amine-modified styrene (meth)acrylic resin is preferably 3000 or more, more preferably 5000 or more. The weight average molecular weight of the amine-modified styrene (meth)acrylic resin is preferably 30000 or less, more preferably 20000 or less. When the weight average molecular weight is within the above range, the coating composition suppresses penetration into paper and obtains good coating properties due to moderate viscosity. The coating composition can also improve adhesion. In this embodiment, the weight average molecular weight is a polystyrene-equivalent weight average molecular weight measured by gel permeation chromatography (hereinafter, GPC) measurement method. Specific measurement of GPC can be performed using HLC-8020 manufactured by Tosoh Corporation as an apparatus, TSKgel SuperHM-M manufactured by Tosoh Corporation as a column, and tetrahydrofuran as an eluent, and can be calculated by comparing with the molecular weight of standard polystyrene.

[0024] The amine value of the amine-modified styrene (meth)acrylic resin is preferably 10 mgKOH / g or more, more preferably 30 mgKOH / g or more. The amine value is preferably 130 mgKOH / g or less, more preferably 100 mgKOH / g or less. In this embodiment, the amine value is a total amine value (mgKOH) measured according to the method of ASTM D2074.

[0025] The glass transition point (Tg) of the amine-modified styrene (meth)acrylic resin is preferably 10°C or higher, more preferably 20°C or higher. Moreover, Tg is preferably 100°C or lower, more preferably 80°C or lower. By having Tg within the above range, the coating composition can have improved curability, improved flexibility after curing, and improved adhesion. In this embodiment, Tg may be calculated from the Tg of the homopolymer of the monomer constituting the resin, or may be measured experimentally. The method of calculation from the Tg of the homopolymer of the monomer is, for example, a method of calculation from the FOX formula. The method of experimental measurement is a method of measuring a DSC curve using a differential scanning calorimeter.

[0026] The content of the amine-modified styrene (meth)acrylic resin may be 5% by mass or more, and preferably 15% by mass or more. The content of the amine-modified styrene (meth)acrylic resin may be 30% by mass or less, and preferably 25% by mass or less. If the content of the amine-modified styrene (meth)acrylic resin is less than 5% by mass, the coating composition may suffer from coating defects such as penetration into paper and repelling (a phenomenon in which circular unevenness occurs), and the adhesion may decrease. On the other hand, if the content of the amine-modified styrene (meth)acrylic resin exceeds 30% by mass, the coating composition may suffer from leveling defects and the adhesion may decrease. By having the content of the amine-modified styrene (meth)acrylic resin within the above range, the coating composition may exhibit better adhesion and impart better gloss when applied to a printed matter (especially a printed matter printed by an electrophotographic method).

[0027] Returning to the description of the resin as a whole, the resin of this embodiment may contain other resins other than the above-mentioned amine-modified styrene (meth)acrylic resin. The other resins are not particularly limited. For example, the other resins are acrylic resins, polyester resins, allyl resins, petroleum resins, epoxy resins, etc.

[0028] When other resins are contained, the content of the other resins is not particularly limited, and is, for example, 5 to 15% by mass.

[0029] (Ethylenically unsaturated compounds) The ethylenically unsaturated compound includes at least one of acryloylmorpholine and vinylcaprolactam.

[0030] The total content of at least one of acryloylmorpholine and vinylcaprolactam may be 41% by mass or more, and is preferably 50% by mass or more. If the total content of at least one of acryloylmorpholine and vinylcaprolactam is less than 41% by mass, the coating composition has a reduced adhesion.

[0031] Returning to the description of the ethylenically unsaturated compounds as a whole, the resin of the present embodiment may contain other ethylenically unsaturated compounds other than the above-mentioned acryloylmorpholine and vinylcaprolactam. The other ethylenically unsaturated compounds are not particularly limited. By way of example, other ethylenically unsaturated compounds include methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, butyl (meth)acrylate, amyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, octyl (meth)acrylate, nonyl (meth)acrylate, dodecyl (meth)acrylate, hexadecyl (meth)acrylate, octadecyl (meth)acrylate, cyclohexyl (meth)acrylate, methoxyethyl (meth)acrylate, butoxyethyl (meth)acrylate, phenoxyethyl (meth)acrylate, nonylphenoxyethyl (meth)acrylate, glycidyl (meth)acrylate, dimethylaminoethyl (meth)acrylate, diethylaminoethyl (meth)acrylate, isobornyl (meth)acrylate, dicyclopentanyl (meth)acrylate, dicyclopentenyl (meth)acrylate, dicyclo Monofunctional (meth)acrylates such as pentenyloxyethyl (meth)acrylate, 2-hydroxy-3-phenoxypropyl (meth)acrylate, tetrahydrofurfuryl (meth)acrylate, 2-hydroxyethyl (meth)acrylate, benzyl (meth)acrylate, phenylbenzyl (meth)acrylate, and mono(2-acryloyloxyethyl)succinate, N-[2-(acryloyloxy)ethyl]phthalimide, N-[2-(acryloyloxy)ethyl]phthalimide, phthalimides such as [ethyl]tetrahydrophthalimide (p-tolyloxy)ethyl]tetrahydrophthalimide, 1,3-butylene glycol di(meth)acrylate, 1,4-butanediol di(meth)acrylate, 1,5-pentanediol di(meth)acrylate, 3-methyl-1,5-pentanediol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, neopentyl glycol di(meth)acrylate, 1,8-octanediol di(meth)acrylate, 1,9-Nonanediol di(meth)acrylate, tricyclodecane dimethanol di(meth)acrylate, ethylene glycol di(meth)acrylate, polyethylene glycol di(meth)acrylate, propylene glycol di(meth)acrylate, dipropylene glycol di(meth)acrylate, tripropylene glycol di(meth)acrylate, polypropylene glycol di(meth)acrylate, neopentyl glycol hydroxypivalate di(meth)acrylate, tris(2-hydroxyethyl)isocyanurate, two water-soluble di(meth)acrylates in which the acid group is substituted with a (meth)acryloyloxy group; di(meth)acrylates in which two hydroxyl groups of a diol obtained by adding 4 or more moles of ethylene oxide or propylene oxide to 1 mole of neopentyl glycol are substituted with a (meth)acryloyloxy group; di(meth)acrylates in which two hydroxyl groups of a diol obtained by adding 2 moles of ethylene oxide or propylene oxide to 1 mole of bisphenol A are substituted with a (meth)acryloyloxy group; Bifunctional (meth)acrylates such as di(meth)acrylates in which two hydroxyl groups of a triol obtained by adding 1 mole or more of ethylene oxide or propylene oxide are substituted with (meth)acryloyloxy groups, and di(meth)acrylates in which two hydroxyl groups of a diol obtained by adding 4 moles or more of ethylene oxide or propylene oxide to 1 mole of bisphenol A are substituted with (meth)acryloyloxy groups, trimethylolpropane tri(meth)acrylate, glycerin triacrylate, pentaerythritol tri(meth)acrylate, trifunctional (meth)acrylates such as tri(meth)acrylate, in which three hydroxyl groups of a triol obtained by adding 3 or more moles of ethylene oxide or propylene oxide to 1 mole of trimethylolpropane are substituted with (meth)acryloyloxy groups; and polyfunctional (meth)acrylates having 4 or more functional groups such as ditrimethylolpropane tetra(meth)acrylate, pentaerythritol tetra(meth)acrylate, dipentaerythritol penta(meth)acrylate, and dipentaerythritol hexa(meth)acrylate.

[0032] When other ethylenically unsaturated compounds are contained, the content of the other ethylenically unsaturated compounds is not particularly limited. For example, the content of the other ethylenically unsaturated compounds is 5 to 50 mass %.

[0033] (Initiator) The initiator is a component that generates radicals when irradiated with active energy rays, and is blended in order to cure the coating composition.

[0034] The initiator is not particularly limited. For example, the initiator may be benzophenone, diethylthioxanthone, 2-methyl-1-(4-methylthio)phenyl-2-morpholinopropan-1-one, 4-benzoyl-4'-methyldiphenyl sulfide, 1-chloro-4-propoxythioxanthone, isopropylthioxanthone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 1-hydroxycyclohexyl phenyl ketone, bis-2,6-dimethoxybenzoyl -2,4,4-trimethylpentylphosphine oxide, 1-[4-(2-hydroxyethoxy)-phenyl]-2-hydroxy-2-methyl-1-propan-1-one, 2,2-dimethyl-2-hydroxyacetophenone, 2,2-dimethoxy-2-phenylacetophenone, 2,4,6-trimethylbenzyl-diphenylphosphine oxide, 2-benzyl-2-dimethylamino-1-(morpholinophenyl)-butan-1-one, etc.

[0035] The content of the initiator is not particularly limited. For example, the content of the initiator in the coating composition is preferably 1% by mass or more, more preferably 2% by mass or more. The content of the initiator in the coating composition is preferably 20% by mass or less, more preferably 15% by mass or less. By having the content of the initiator within the above range, the coating composition is easily cured sufficiently.

[0036] (Polymerization inhibitor) The polymerization inhibitor includes a piperidine derivative. The piperidine derivative is not particularly limited. For example, the piperidine derivative may be a linear or cyclic condensation product of N,N'-bis(2,2,6,6-tetramethyl-4-piperidyl)hexamethylenediamine and 4-tert-octylamino-2,6-dichloro-1,3,5-triazine, a linear or cyclic condensation product of N,N'-bis(2,2,6,6-tetramethyl-4-piperidyl)-hexamethylenediamine and 4-morpholino-2,6-dichloro-1,3,5-triazine, a linear or cyclic condensation product of 2-chloro-4,6-di(4-n-butylamino-2,2,6,6-tetramethylpiperidyl)-1,3,5-triazine and 1,2-bis( 3-aminopropylamino)ethane condensation product, 2-chloro-4,6-di(4-n-butylamino-1,2,2,6,6-pentamethylpiperidyl)-1,3,5-triazine and 1,2-bis(3-aminopropylamino)ethane condensation product, N,N'-bis-(2,2,6,6-tetramethyl-4-piperidyl)hexamethylenediamine and 4-chlorohexylamino-2,6-dichloro-1,3,5-triazine condensation product, 2,2,6,6-tetramethylpiperidine 1-oxyl, 4-hydroxy-2,2,6,6-tetramethylpiperidine 1-oxyl, etc.

[0037] The content of the piperidine derivative may be 0.05% by mass or more, preferably 0.1% by mass or more, and more preferably 0.2% by mass or more. The content of the piperidine derivative may be 1% by mass or less, preferably 0.8% by mass or less, and more preferably 0.5% by mass or less. If the content of the piperidine derivative is less than 0.05% by mass, the coating composition will gel under fluorescent light and the viscosity will increase over time. On the other hand, if the content of the piperidine derivative is more than 1% by mass, the curability of the coating composition will decrease.

[0038] Returning to the explanation of the polymerization inhibitor as a whole, the polymerization inhibitor of the present embodiment may contain other polymerization inhibitors other than the piperidine derivatives described above. The other polymerization inhibitors are not particularly limited. For example, the other polymerization inhibitors are nitroso compounds, phenol compounds, quinone compounds, etc.

[0039] When the other polymerization inhibitor is contained, the content of the other polymerization inhibitor is not particularly limited, and is, for example, 0.05 to 1 mass %.

[0040] (optional ingredient) The coating composition of the present embodiment may contain optional components in addition to the above components. The optional components are not particularly limited. Examples of the optional components include leveling agents, antibacterial agents, antistatic agents, surfactants, antifoaming agents, antioxidants, waxes, slip agents, etc.

[0041] Returning to the description of the coating composition as a whole, the active energy ray is not particularly limited. For example, the active energy ray may be ultraviolet light, electron beam, X-ray, ionizing radiation such as α-ray, β-ray, γ-ray, microwave, high frequency wave, etc., or may be visible light, infrared light, laser beam, etc.

[0042] 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.

[0043] The viscosity of the coating composition of the present embodiment at 25°C should be 40 mPa·s or more, preferably 60 mPa·s or more. Also, the viscosity should be 380 mPa·s or less, preferably 299 mPa·s or less. When the viscosity of the coating composition is within the above range, the leveling property is excellent and it is easy to apply. In the present embodiment, the viscosity is measured at 25°C using a rheometer (Discovery HR-2, manufactured by TA instruments) at a shear rate of 100 s -1 and reading the viscosity.

[0044] The object to which the coating composition of the present embodiment is applied is not particularly limited. For example, the object may be a printed matter printed by an electrophotographic method, a printed matter printed by an inkjet method, an offset-printed matter, a flexo-printed matter, plastic, paper, cardboard, etc. Among these, the coating composition of the present embodiment is preferably applied to a printed matter printed by an electrophotographic method. That is, a printed matter printed by an electrophotographic method has a difference in that it contains more wax and silicone components compared to, for example, an offset-printed matter. Therefore, a printed matter printed by an electrophotographic method is more likely to have inferior adhesion of the coating composition and is less likely to be imparted with glossiness compared to an offset-printed matter. However, the coating composition of the present embodiment has a small environmental load, exhibits excellent adhesion, and can impart excellent glossiness. In the present embodiment, the "printed matter printed by an electrophotographic method" includes all printed matters printed by a method of electrostatically adhering toner to a drum and transferring it to an output material.

[0045] The base material of the printed matter is not particularly limited. For example, the base material may be coated paper such as art paper, coated paper, cast paper, uncoated paper such as fine paper and medium paper, synthetic paper such as Yupo paper, or plastic films such as PET (polyethylene terephthalate), PP (polypropylene), and OPP (biaxially stretched polypropylene).

[0046] The coating composition can be cured in a short time by irradiating it with active energy rays after application to form a film, which helps reduce production costs. Furthermore, the coating composition does not contain organic solvents and does not release VOCs into the atmosphere, so it has a low environmental impact.

[0047] The method for preparing the coating composition of the present embodiment is not particularly limited. As an example, the coating composition can be prepared by appropriately mixing the above-mentioned components and stirring them with a stirrer.

[0048] The method of applying the coating composition of the present embodiment to a printed matter (particularly a printed matter printed by an electrophotographic method) is not particularly limited. For example, the coating composition can be applied to the printed matter by a known method such as bar coating, gravure coating, flexo coating, roll coating, reverse roll coating, or comma coating.

[0049] The applied coating composition can be cured by irradiation with active energy rays. The irradiation conditions of the active energy rays are not particularly limited. The irradiation conditions may be any conditions that allow the applied coating composition to be sufficiently cured.

[0050] The thickness of the obtained cured film is not particularly limited. For example, the thickness is preferably 4 μm or more, more preferably 6 μm or more. The thickness is preferably 10 μm or less, more preferably 8 μm or less.

[0051] As described above, according to the present embodiment, the coating composition imparts little environmental load, exhibits excellent adhesion, and can impart excellent glossiness when applied to a printed matter (particularly a printed matter printed by an electrophotographic method). As a result, the resulting coating composition exhibits excellent adhesion and excellent glossiness. EXAMPLES

[0052] The present invention will be described in more detail below with reference to examples and comparative examples. The present invention is not limited to these examples. Each value in the table is based on mass %.

[0053] The raw materials used are as follows: <Resin> The amine-modified styrene (meth)acrylic resins 1 and 2, the amine-modified (meth)acrylic resin, and the styrene (meth)acrylic resin were used, each having the components and properties shown in the following Table 1. The abbreviations in Table 1 are as follows. DM N,N-Dimethylaminoethyl methacrylate St Styrene BA Butyl Acrylate 2-HEA 2-Ethylhexyl acrylate BMA Butyl Methacrylate CHMA Cyclohexyl methacrylate MMA Methyl methacrylate

[0054] (Synthesis Example 1 of Amine Modified Styrene (Meth) Acrylic Resin 1) A reaction vessel equipped with a nitrogen gas inlet tube, a thermometer, a condenser, and a stirrer was charged with 90.1 parts of methyl ethyl ketone (MEK) and replaced with nitrogen gas. The reaction vessel was heated to 110°C, and a mixture of 33.0 parts of N,N-dimethylaminoethyl methacrylate, 57.0 parts of styrene, 10.0 parts of butyl acrylate, and a 9.0% mixture of 2,2'-azobis(2-methylpropionate)dimethyl (V-601, manufactured by Wako Pure Chemical Industries, Ltd.) as a polymerization initiator was added dropwise over 2 hours to carry out a polymerization reaction. After the dropwise addition, the mixture was reacted at 110°C for another 3 hours, and then 0.9 parts of V-601 was added and reacted at 110°C for 1 hour. MEK was then removed under reduced pressure to obtain an amine-modified styrene-acrylic polymer 1 (weight average molecular weight 9800, amine value 118mgKOH / g).

[0055] Amine-modified styrene (meth)acrylic resin 2, amine-modified (meth)acrylic resin and styrene (meth)acrylic resin were also obtained in the same manner as in Synthesis Example 1, except that the raw materials and amounts were changed to those shown in Table 1.

[0056] [Table 1]

[0057] <Resin> Vylon 220: Polyester resin (Toyobo Co., Ltd., amorphous polyester resin, molecular weight 3,000, hydroxyl value 50 mgKOH / g, Tg 53°C) Neopolymer S: Petroleum resin (ENEOS Corporation, aromatic (C9) hydrocarbon resin, molecular weight 1,100, softening point 92°C) UN-7770: Urethane oligomer (manufactured by Negami Chemical Industries, urethane oligomer with ester structure, molecular weight 20,000, Tg-41℃) <Ethylenically unsaturated compounds> ACMO: Acryloylmorpholine (KJ Chemicals, monofunctional monomer) VCAP: Vinylcaprolactam (BASF Japan, monofunctional monomer) Viscoat 160: Benzyl acrylate (manufactured by Osaka Organic Chemical Industry Co., Ltd., monofunctional acrylate) LA: Lauryl acrylate (Osaka Organic Chemical Industry Co., Ltd., monofunctional acrylate) TPGDA: Tripropylene glycol diacrylate (Osaka Organic Chemical Industry, Ltd., bifunctional acrylate) A-NOD-N: 1,9-nonanediol diacrylate (manufactured by Shin-Nakamura Chemical Co., Ltd., bifunctional acrylate) <Initiator> DAIDO UV-CURE 819: Phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide (manufactured by Daido Chemical Industry Co., Ltd.) <Photosensitizer> Tinopal OBCO: 2,5-bis(5'-t-butylbenzoxazolyl-2')thiophene (manufactured by BASF Japan) Chemark DETX: 2,4-diethylthioxanthone (manufactured by Chemark Chemical) <Polymerization inhibitor> Polystop 7300P: Piperidine derivative (Hakutosha) TEMPO: 2,2,6,6 - Tetramethylpiperidine 1 - oxyl (manufactured by Sankyo Chemical Co., Ltd.) H - BHT: Dibutylhydroxytoluene (manufactured by Honshu Chemical Industry Co., Ltd.) TBHQ FINE: t - Butylhydroquinone (manufactured by Kusumoto Chemical Co., Ltd.) Q - 1301: N - Nitroso - N - phenylhydroxylamine aluminum (manufactured by Wako Pure Chemical Industries, Ltd.) ADK STAB 260: 4,4’ - Butylidenebis(3 - methyl - 6 - t - butylphenyl - di - tridecyl phosphite) (manufactured by ADEKA Corporation)

[0058] <Example 1> According to the formulation described in Table 2, each component was mixed and stirred and mixed with a disper at 60°C for 30 minutes to prepare the coating composition of Example 1. For the obtained coating composition, viscosity, coatability, adhesion, curability, and fluorescent lamp stability were evaluated by the following evaluation methods. The results are shown in Table 2.

[0059] <Examples 2 to 11, Comparative Examples 1 to 20> Coating compositions were prepared and evaluated in the same manner as in Example 1, except that the formulations described in Tables 2 to 4 were changed. The results are shown in Tables 2 to 4.

[0060] <Paint Performance Confirmation Conditions> (Viscosity) Measured using a rheometer Discovery HR - 2 manufactured by TA Instruments at 25°C and a shear rate of 100 s -1 under the conditions of. (Fluorescent Lamp Stability) The presence or absence of gelation at 1 m (825 lux) under a 25°C, three - wavelength daylight white fluorescent lamp was evaluated according to the following evaluation criteria. ○: The coating composition did not gel for 5 hours or more. △○: The coating composition gelled in more than 3 hours and less than 5 hours. △: The coating composition gelled in more than 1 hour and less than 3 hours. ×: The coating composition gelled in less than 1 hour.

[0061] <Conditions for checking coating performance> (Conditions for preparing test specimens) Printed matter 1 to 3 were produced by electrophotography using printing machines of the following three companies that are widely used in this field. A coating composition was applied to each of the obtained electrophotographic printed matter 1 to 3 using a bar coater #5, and the coating composition was applied using LED-UV (385 nm) UVA integrated light amount of 300 mJ / cm. 2 Under these conditions, the resin was irradiated with ultraviolet light and cured. Electrophotographic printing 1 (using HP printer) Electrophotographic printing 2 (using a Ricoh printer) Electrophotographic printing 3 (using Canon printer) (Coatability) The coating composition was applied to the printed matter using a bar coater #5, and the leveling was evaluated according to the following criteria. ◯: Smooth and good leveling. △◯: Slight flow marks (phenomenon in which coating streaks (unevenness) occur along the coating direction), repelling (phenomenon in which circular unevenness occurs), and soaking into the paper were observed. △: There were some flow marks, repelling, and penetration into the paper. ×: Flow marks, repelling, and soaking into the paper were observed over the entire surface, and the leveling properties were poor. (gloss value) The 60° reflected gloss value of the coated surface of the test piece was determined using a VG8000 gloss meter manufactured by Nippon Denshoku Industries Co., Ltd. (curable) The test pieces prepared by the above method were evaluated for dryness to touch according to the following criteria. ◯: The coating film had no tack. △◯: The coating film was slightly tacky. △: The coating film was tacky. ×: The coating film left a mark when touched with a finger. (Adhesion) The adhesion of the test pieces prepared by the above method to various printed materials 1 to 3 (printed using HP, RICOH, and CANON printing machines) was evaluated according to the following evaluation criteria by attaching a 12 mm wide adhesive tape (Nichiban Co., Ltd., cellophane tape) to the test piece and peeling it off at an angle of 90° to the test piece. A: The coating film did not peel off. △◯: The coating film remaining rate was 70% or more. △: The coating film remaining rate was 30 to 69%. ×△: The coating film remaining rate was 1 to 29%. ×: The coating film peeled off over the entire surface.

[0062] [Table 2]

[0063] [Table 3]

[0064] [Table 4]

[0065] As shown in Tables 2 to 4, it was found that the coating compositions of Examples 1 to 11 of the present invention exhibited excellent adhesion and were capable of imparting excellent gloss.

Claims

1. A composition comprising a resin, an ethylenically unsaturated compound, an initiator, and a polymerization inhibitor, the resin comprises an amine-modified styrene (meth)acrylic resin, The content of the amine-modified styrene (meth)acrylic resin is 5 to 30% by mass, The ethylenically unsaturated compound includes at least one of acryloylmorpholine and vinylcaprolactam, The total content of at least one of the acryloylmorpholine and the vinylcaprolactam is 41 mass% or more, The polymerization inhibitor includes a piperidine derivative, The content of the piperidine derivative is 0.05 to 1% by mass, The active energy ray-curable coating composition has a viscosity at 25° C. of 40 to 380 mPa·s.

2. 2. The active energy ray-curable coating composition according to claim 1, wherein the content of the amine-modified styrene (meth)acrylic resin is 15 to 25 mass %.

3. 3. The active energy ray-curable coating composition according to claim 1, wherein the viscosity at 25° C. is 40 to 299 mPa·s.

4. 3. The active energy ray-curable coating composition according to claim 1 or 2, which is applied to a printed matter printed by an electrophotographic method.

5. 3. A coated printed material, comprising: a coating composition according to claim 1 or 2 applied to a printed material printed by an electrophotographic method.

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