Active energy ray-curable inkjet printing ink composition

Abstract

The present invention aims to provide an active energy ray-curable inkjet printing ink composition having low viscosity, no odor in the cured coating film, excellent curability, no tackiness, and excellent bending resistance, abrasion resistance and water resistance of the cured coating film. The active energy ray-curable inkjet printing ink composition satisfies the following conditions A to E. (A) 1.0 to 20.0% by mass of an amine-modified oligomer; (B) 2.0 to 20.0% by mass of a (meth)acrylate monomer having an alkoxy group; (C) 2.0 to 25.0% by mass of a (meth)acrylate monomer having an alkyl group having 6 to 20 carbon atoms; (D) 30.0 to 60.0% by mass of at least one selected from 1,6-hexanediol diacrylate, 3-methyl-1,5-pentanediol diacrylate, dipropylene glycol diacrylate, 1,10-decanediol diacrylate, propoxylated (2) neopentyl glycol diacrylate and hydroxypivalate neopentyl glycol diacrylate; and (E) a photopolymerization initiator, which is contained in an active energy ray-curable inkjet printing ink composition in an amount of 6.0 to 25.0% by mass.

Description

Technical Field

[0001] The present invention relates to an active energy ray-curable inkjet printing ink composition and a printed matter obtained using the same. The active energy ray-curable inkjet printing ink composition is suitable for printing on substrates such as sheets composed of resins such as paper, vinyl chloride polymers or ethylene-vinyl acetate copolymers, especially on paper such as corrugated cardboard. Background Art

[0002] As described in Patent Document 1, it is well known that preventing the occurrence of curing wrinkles during the curing of photocurable inkjet inks is a major issue.

[0003] In addition, an inkjet ink composition containing an amine-modified oligomer and an alkoxy-containing monomer is also known, as described in Patent Document 2. However, this ink composition does not satisfy the conditions C or D of the present invention.

[0004] Furthermore, as awareness of environmental protection increases, attention is also being paid to the need to minimize waste generation by reconsidering the materials of items used in daily life.

[0005] Patent Literature

[0006] Patent Document 1: International Publication No. 2007 / 074768

[0007] Patent Document 2: International Publication No. 2017 / 073654 Summary of the invention

[0008] The problem to be solved by the present invention is to provide an active energy ray-curable inkjet printing ink composition having low viscosity, no odor in the cured coating film, excellent curability, no tackiness, and excellent bending resistance, abrasion resistance and water resistance of the cured coating film.

[0009] The present inventors have conducted intensive studies to solve the above-mentioned problems, and as a result, have found that the above-mentioned problems can be solved by a specific composition, thereby completing the present invention.

[0010] That is, the present invention is as follows.

[0011] 1. An active energy ray-curable inkjet printing ink composition, characterized in that it satisfies the following conditions (A) to (E):

[0012] (A) The content of the amine-modified oligomer is 1.0 to 20.0% by mass in the active energy ray-curable inkjet printing ink composition;

[0013] (B) the active energy ray-curable inkjet printing ink composition contains 2.0 to 20.0% by mass of a (meth)acrylate monomer having an alkoxy group;

[0014] (C) an active energy ray-curable inkjet printing ink composition containing 2.0 to 25.0% by mass of a (meth)acrylate monomer having an alkyl group having 6 to 20 carbon atoms;

[0015] (D) an active energy ray-curable inkjet printing ink composition containing 30.0 to 60.0% by mass of at least one selected from 1,6-hexanediol diacrylate, 3-methyl-1,5-pentanediol diacrylate, dipropylene glycol diacrylate, 1,10-decanediol diacrylate, propoxylated (2) neopentyl glycol diacrylate, and hydroxypivalate neopentyl glycol diacrylate;

[0016] (E) As a photopolymerization initiator, the active energy ray-curable ink jet printing ink composition contains 3.0 to 15.0 mass % of ethoxy(2,4,6-trimethylbenzoyl)phenylphosphine oxide, and the active energy ray-curable ink jet printing ink composition contains 2.0 to 10.0 mass % of oligo(2-hydroxy-2-methyl-1-(4-(1-methylvinyl)phenyl)propanone) and / or 2-hydroxy-1-{4-〔4-(2-hydroxy-2-methylpropionyl)phenoxy〕phenyl}-2-methylpropanone, and the total content of the photopolymerization initiators is 6.0 to 25.0 mass % in the active energy ray-curable ink jet printing ink composition.

[0017] 2. The active energy ray-curable ink composition for inkjet printing according to 1, characterized in that at least a part of the (meth)acrylate monomer having an alkoxy group of (B) is a multifunctional (meth)acrylate monomer, and the active energy ray-curable ink composition for inkjet printing contains 5.0 to 20.0% by mass of the multifunctional (meth)acrylate monomer.

[0018] 3. The active energy ray-curable inkjet printing ink composition according to 1 or 2, wherein the one of the (meth)acrylate monomers having an alkyl group having 6 to 20 carbon atoms is lauryl acrylate and / or stearyl acrylate.

[0019] 4. The active energy ray-curable inkjet printing ink composition according to any one of 1 to 3, wherein one of the (meth)acrylate monomers having an alkyl group having 6 to 20 carbon atoms is lauryl acrylate synthesized using a plant-derived compound.

[0020] 5. The active energy ray-curable inkjet printing ink composition according to any one of 1 to 4, wherein the 1,10-decanediol diacrylate is synthesized using a plant-derived compound.

[0021] 6. The active energy ray-curable inkjet printing ink composition according to any one of 1 to 5, further comprising (F) a colorant.

[0022] The active energy ray-curable inkjet printing ink composition of the present invention has low viscosity, and the cured coating film has no odor, excellent curability, no tackiness, and the cured coating film has excellent bending resistance, abrasion resistance and water resistance. DETAILED DESCRIPTION

[0023] The active energy ray-curable inkjet printing ink composition of the present invention satisfies the above conditions A to E, which will be described in order below.

[0024] <Condition A>

[0025] As condition A, the content of the amine-modified oligomer in the active energy ray-curable inkjet printing ink composition is 1.0 to 20.0% by mass. Among them, acrylated amine compounds having two photopolymerizable functional groups and two amino groups in the molecule are preferred.

[0026] Here, the acrylated amine compound having two photopolymerizable functional groups and two amino groups in the molecule is not particularly limited. For example, the photopolymerizable functional group in the acrylated amine compound can be a functional group that can form a cross-linked bond between molecules by polymerization reaction by visible light or invisible light including ionizing radiation such as ultraviolet rays or electron beams. In addition, the photopolymerizable functional group includes both the following: a photopolymerizable functional group in a narrow sense that undergoes photopolymerization reaction by direct activation by light irradiation; and a photopolymerizable functional group in a broad sense that initiates polymerization reaction and is promoted by the action of active species generated by the photopolymerization initiator when the photopolymerizable functional group and the photopolymerization initiator coexist and are irradiated with light.

[0027] The photopolymerizable functional group is a functional group reactive with photo-radical polymerization such as ethylenic double bonds, a functional group reactive with photo-cationic polymerization and photo-anionic polymerization such as cyclic ether groups such as epoxy groups, etc. Among them, the photopolymerizable functional group is preferably an ethylenic double bond such as (meth)acryloyl, vinyl, and allyl, and more preferably a (meth)acryloyl.

[0028] In the acrylated amine compound having two photopolymerizable functional groups and two amino groups in the molecule, both of the two photopolymerizable functional groups are (meth)acryloyl groups, and the amine value is preferably 130 to 142 KOHmg / g. In addition, the amine value refers to the amine value per 1g of the solid content, which is measured using a 0.1N hydrochloric acid aqueous solution by a potentiometric titration method (for example, COMTITE (AUTOTITRATOR COM-900, BURET B-900, TITSTATION K-900), manufactured by Hiranuma Sangyo Co., Ltd.), and then converted into a value equivalent to potassium hydroxide.

[0029] The acrylated amine compound having two photopolymerizable functional groups and two amino groups in the molecule is preferably an acrylated amine compound obtained by reacting a bifunctional (meth)acrylate with an amine compound.

[0030] The bifunctional (meth)acrylates include alkylene glycol di(meth)acrylates such as 1,4-butanediol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, 1,9-nonanediol di(meth)acrylate, propylene glycol di(meth)acrylate, 1,3-butanediol di(meth)acrylate, and neopentyl glycol di(meth)acrylate, di(meth)acrylates of ethylene oxide adducts of bisphenol A, and di(meth)acrylates of ethylene oxide adducts of bisphenol F. Bisphenol alkylene oxide adduct di(meth)acrylates such as bisphenol S ethylene oxide adduct di(meth)acrylate, bisphenol S ethylene oxide adduct di(meth)acrylate, bisphenol S ethylene oxide adduct di(meth)acrylate, bisphenol A bromide ethylene oxide adduct di(meth)acrylate, polyethylene glycol di(meth)acrylate, polypropylene glycol di(meth)acrylate, etc., di(meth)acrylate of neopentyl glycol hydroxypivalate, etc. Among them, the bifunctional (meth)acrylate is preferably 1,6-hexanediol di(meth)acrylate.

[0031] The amine compound includes monofunctional amine compounds such as benzylamine, phenylethylamine, ethylamine, n-propylamine, isopropylamine, n-butylamine, isobutylamine, n-pentylamine, isopentylamine, n-hexylamine, cyclohexylamine, n-heptylamine, n-octylamine, 2-ethylhexylamine, n-nonylamine, n-decylamine, n-dodecylamine, n-tetradecylamine, n-hexadecylamine, and n-octadecylamine, and polyfunctional amine compounds such as diethylenetriamine, triethylenetetramine, tetraethylenepentamine, 1,6-hexamethylenediamine, 1,8-octamethylenediamine, 1,12-dodecamethylenediamine, o-phenylenediamine, p-phenylenediamine, m-phenylenediamine, o-xylylenediamine, p-xylylenediamine, m-xylylenediamine, menthanediamine, bis(4-amino-3-methylcyclohexyl)methane, isophoronediamine, 1,3-diaminocyclohexane, and spiroacetal diamine. Furthermore, the amine compound may be a high molecular weight type polyfunctional amine compound such as polyethyleneimine, polyvinylamine, polyallylamine, or the like.

[0032] The acrylated amine compound having two photopolymerizable functional groups and two amino groups in the molecule is preferably a compound obtained by reacting 1,6-hexanediol di(meth)acrylate with an amine compound. Specifically, it is an acrylated amine compound such as CN371, CN373, CN383, CN386 (manufactured by Sartomer) which is an oligomer of an acrylated amine compound having two active energy ray polymerizable functional groups and two amino groups in the molecule. Furthermore, EB7100 (EBECRYL7100, manufactured by SITECH) and Agi008 (manufactured by DSM) can also be used.

[0033] The content of the amine-modified oligomer in the active energy ray-curable inkjet printing ink composition is 1.0% by mass or more, preferably 3.0% by mass or more, more preferably 4.0% by mass or more, and even more preferably 5.0% by mass or more.

[0034] The content of the amine-modified oligomer in the active energy ray-curable inkjet printing ink composition is 20.0% by mass or less, preferably 15.0% by mass or less, more preferably 12.0% by mass or less, and most preferably 9.0% by mass or less.

[0035] When the content of the amine-modified oligomer is less than 1.0% by mass, the curability of the active energy ray-curable inkjet printing ink composition tends to be poor. On the other hand, when the content exceeds 20.0% by mass, the storage stability and ejection stability of the ink composition tend to be reduced.

[0036] The content of the amine-modified oligomer is preferably 2.0% by mass or more, more preferably 3.0% by mass or more, and even more preferably 4.0% by mass or more, based on the total photopolymerizable components in the active energy ray-curable inkjet printing ink composition.

[0037] The content of the amine-modified oligomer is preferably 16.0% by mass or less, more preferably 10.0% by mass or less, and even more preferably 8.0% by mass or less, based on the total photopolymerizable components in the active energy ray-curable inkjet printing ink composition.

[0038] <Condition B>

[0039] As condition B, the active energy ray-curable inkjet printing ink composition contains 2.0 to 20.0% by mass of the (meth)acrylate monomer having an alkoxy group in the total polymerizable components.

[0040] The (meth)acrylate monomer having an alkoxy group is not particularly limited. For example, the (meth)acrylate monomer includes various monofunctional (meth)acrylate monomers with little odor, bifunctional (meth)acrylate monomers, trifunctional (meth)acrylate monomers, and polyfunctional acrylate monomers having four or more functions. In consideration of the environment, a (meth)acrylate monomer having an alkoxy group derived from biomass can be used.

[0041] Specifically, there can be mentioned: monofunctional alkoxyalkyl (meth)acrylates such as 2-methoxyethyl (meth)acrylate, 2-ethoxyethyl (meth)acrylate, 2-methoxybutyl (meth)acrylate, 2-(2-ethoxyethoxy)ethyl acrylate, 3-methoxybutyl (meth)acrylate, and 2-butoxyethyl (meth)acrylate; 2-butoxydiethylene glycol (meth)acrylate, methoxydiethylene glycol (meth)acrylate, methoxytriethylene glycol (meth)acrylate, and methoxytriethylene glycol (meth)acrylate. Monofunctional (meth)acrylates containing a polyalkylene glycol structure and an alkoxy group, such as glycol (meth)acrylate, ethoxydiethylene glycol (meth)acrylate, methoxydipropylene glycol (meth)acrylate, methoxytripropylene glycol (meth)acrylate, methoxypolyethylene glycol (meth)acrylate, octyloxypolyethylene glycol-polypropylene glycol-mono(meth)acrylate, dodecyloxypolyethylene glycol mono(meth)acrylate, and stearyloxypolyethylene glycol mono(meth)acrylate.

[0042] Furthermore, polyfunctional (meth)acrylates containing an alkoxy group such as ethoxylated (3) trimethylolpropane tri(meth)acrylate, propoxylated (2) neopentyl glycol di(meth)acrylate, propoxylated (2) neopentyl glycol diacrylate, etc. can also be used.

[0043] The alkoxy group-containing (meth)acrylate in condition B preferably contains 30 to 100 mass % of the alkoxy group-containing polyfunctional (meth)acrylate in condition B. When the alkoxy group-containing polyfunctional (meth)acrylate is within this range, the abrasion resistance is excellent.

[0044] The content of the alkoxy group-containing (meth)acrylate monomer in the active energy ray-curable inkjet printing ink composition is preferably 5.0% by mass or more, and more preferably 10.0% by mass or more.

[0045] The content of the alkoxy group-containing (meth)acrylate monomer in the active energy ray-curable inkjet printing ink composition is preferably 18.0% by mass or less, more preferably 16.0% by mass or less, and even more preferably 14.0% by mass or less.

[0046] If the content of the alkoxy group-containing (meth)acrylate monomer in the active energy ray-curable inkjet printing ink composition is less than 2.0 mass %, the bending resistance will be poor, and if it exceeds 20.0 mass %, the water resistance will be poor.

[0047] The content of the alkoxy-containing (meth)acrylate monomer in the total polymerizable components of the active energy ray-curable inkjet printing ink composition is preferably 6.0% by mass or more, more preferably 10.0% by mass or more, and even more preferably 12.0% by mass or more. In addition, it is preferably 20.0% by mass or less, even more preferably 18.0% by mass or less, and even more preferably 16.0% by mass or less.

[0048] <Condition C>

[0049] As condition C, the active energy ray-curable inkjet printing ink composition contains 2.0 to 25.0 mass % of a (meth)acrylate having an alkyl group having 6 to 20 carbon atoms. The alkyl group having 6 to 20 carbon atoms may have any of a linear, branched, and alicyclic structure.

[0050] Here, the (meth)acrylate containing an alkyl group having 6 to 20 carbon atoms is a monofunctional (meth)acrylate.

[0051] Examples thereof include tridecyl (meth)acrylate, lauryl (meth)acrylate, stearyl (meth)acrylate, isoamyl (meth)acrylate, isodecyl (meth)acrylate, isotetradecyl (meth)acrylate, isobornyl (meth)acrylate, cyclohexyl (meth)acrylate, etc. Preferred are stearyl acrylate and lauryl acrylate.

[0052] The content of the (meth)acrylate containing an alkyl group having 6 to 20 carbon atoms in the active energy ray-curable inkjet printing ink composition is 2.0% by mass or more, preferably 5.0% by mass or more, and more preferably 7.0% by mass or more.

[0053] The active energy ray-curable inkjet printing ink composition contains a (meth)acrylate having an alkyl group having 6 to 20 carbon atoms in an amount of 25.0% by mass or less, more preferably 18.0% by mass or less, and even more preferably 15.0% by mass or less.

[0054] If the content of the (meth)acrylate containing a C 6-20 alkyl group in the active energy ray-curable inkjet printing ink composition is less than 2.0 mass %, the bending resistance will be poor, and if it exceeds 25.0 mass %, the abrasion resistance will be poor.

[0055] The content of the (meth)acrylate containing an alkyl group having 6 to 20 carbon atoms in the total polymerizable components of the active energy ray-curable inkjet printing ink composition is preferably 7.0% by mass or more, more preferably 9.0% by mass or more, and even more preferably 10.0% by mass or more. In addition, it is preferably 25.0% by mass or less, more preferably 22.0% by mass or less, and even more preferably 18.0% by mass or less.

[0056] One of the raw materials of the (meth)acrylate containing an alkyl group having 6 to 20 carbon atoms is (meth)acrylic acid, and the other raw material is an alcohol having 6 to 20 carbon atoms. The alcohol can be obtained from a plant-derived raw material, for example, and is a substance having renewable carbon. The plant-derived raw material includes plant raw materials such as palm oil, palm kernel oil, and coconut oil.

[0057] Since the alkyl group having 6 to 20 carbon atoms has a large number of carbon atoms, the more (meth)acrylate used as a raw material in the active energy ray-curable inkjet printing ink composition is used, the more biomass-derived carbon can be used in the entire composition.

[0058] <Condition D>

[0059] As condition D, at least one selected from 1,6-hexanediol diacrylate, 3-methyl-1,5-pentanediol diacrylate, dipropylene glycol diacrylate, 1,10-decanediol diacrylate, propoxylated (2) neopentyl glycol diacrylate, and hydroxypivalate neopentyl glycol diacrylate is used. The total content of the compounds in condition D is 30.0 to 60.0% by mass in the active energy ray-curable inkjet printing ink composition.

[0060] In addition, when the total amount under condition D is less than 30.0 mass %, the friction resistance is poor, and when it exceeds 60.0 mass %, the bending resistance is poor.

[0061] In addition, plant-derived substances are used as raw materials for these compounds.

[0062] <Condition E>

[0063] In condition E, the active energy ray-curable inkjet printing ink composition contains 3.0 to 15.0 mass% of ethoxy(2,4,6-trimethylbenzoyl)phenylphosphine oxide as a photopolymerization initiator, and the active energy ray-curable inkjet printing ink composition contains 2.0 to 10.0 mass% of oligo(2-hydroxy-2-methyl-1-(4-(1-methylvinyl)phenyl)propanone) and / or 2-hydroxy-1-{4-〔4-(2-hydroxy-2-methylpropionyl)phenoxy〕phenyl}-2-methylpropanone, and the total content of the photopolymerization initiator is 6.0 to 25.0 mass% in the active energy ray-curable inkjet printing ink.

[0064] Regarding the content of the photopolymerization initiator used in condition E, for example, when ultraviolet rays (UV lamp) or ultraviolet rays (light emitting diode (LED)) are used as the light source, the content of the photopolymerization initiator is preferably 6.0% by mass or more, and more preferably 8.0% by mass or more in the active energy ray-curable inkjet printing ink composition. In addition, the content of the photopolymerization initiator is preferably 25.0% by mass or less, and more preferably 15.0% by mass or less in the active energy ray-curable inkjet printing ink composition. When the content of the photopolymerization initiator is within the above range, the active energy ray-curable inkjet printing ink composition can have sufficient curability, internal curability, and low cost.

[0065] The active energy ray-curable inkjet printing ink composition of the present invention may further contain a photopolymerization initiator other than the above-mentioned ones within the range not impairing the effects of the present invention. In addition, when electron beams are used as active energy beams, a photopolymerization initiator may or may not be contained.

[0066] As the photopolymerization initiator which can be used, for example, the following can be mentioned.

[0067] Examples of the acylphosphine oxide-based polymerization initiator include bis-2,6-dimethoxybenzoyl-2,4,4-trimethylpentylphosphine oxide, 2,4,6-trimethylbenzyl-diphenylphosphine oxide (TPO), and bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide.

[0068] As α-hydroxyketone polymerization initiators, there are 2-hydroxy-1-{4-〔4-(2-hydroxy-2-methyl-propionyl)-benzyl〕-phenyl}-2-methyl-propane-1-one (Irgacure 127), 2-hydroxy-4'-hydroxyethoxy-2-methylpropiophenone (Irgacure 2959), 1-hydroxycyclohexyl phenyl ketone (Irgacure 184), 2-hydroxy-2-methyl-1-phenylpropane-1-one, 1-[4-(2-hydroxyethoxy)-phenyl]-2-hydroxy-2-methyl-1-propane-1-one, 1-hydroxycyclohexyl phenyl ketone, and the like.

[0069] In addition, there are benzophenone compounds (4,4'-diethylaminobenzophenone, etc.) and thioxanthone compounds (2,4-diethylthioxanthone), 2-methyl-1-(4-methylthio)phenyl-2-morpholinopropane-1-one, 4'-(methylthio)-α-morpholino-α-methylpropiophenone, phenylthio compounds (4-benzoyl-4'-methyldiphenyl sulfide), 1-chloro-4-propoxythioxanthone, isopropylthioxanthone, 2,2-dimethyl-2-hydroxyacetophenone, 2,2-dimethoxy-2-phenylacetophenone, 2-benzyl-2-dimethylamino-1-(morpholinophenyl)-butane-1-one, 4-benzoyl-4'-methyldiphenyl sulfide, ethyl Michler's ketone, polymer type initiators (Omnipol TP, Omnipol BP), 1-〔4-(4-benzoylphenylsulfanyl)phenyl〕-2-methyl-2-(4-methylphenylsulfonyl)propan-1-one (ESACURE1001M).

[0070] Such photopolymerization initiators are commercially available, and can be obtained, for example, by purchasing trade names such as Irgacure 907, Irgacure 369, Irgacure 184, Irgacure 379, Irgacure 819, and TPO. A plurality of photopolymerization initiators may be used in combination.

[0071] (Sensitizer)

[0072] Furthermore, in order to promote the curing property of ultraviolet rays using a light emitting diode (LED) as a light source, the active energy ray-curable inkjet printing ink composition of the present invention may further use the following photosensitizer (compound) together with the polymerization initiator: having light absorption characteristics mainly in the ultraviolet wavelength region of 400 nm or more, and exhibiting a sensitizing function of the curing reaction by light of wavelengths in this range. In addition, the so-called "exhibiting a sensitizing function by light of wavelengths of 400 nm or more" means having light absorption characteristics in the wavelength region of 400 nm or more. By using such a sensitizer, the ink composition of this embodiment can promote LED curing.

[0073] Examples of such sensitizers include anthracene-based sensitizers and thioxanthone-based sensitizers, and thioxanthone-based sensitizers are preferred. These sensitizers may be used alone or in combination of two or more.

[0074] Specifically, anthracene sensitizers such as 9,10-dibutoxyanthracene, 9,10-diethoxyanthracene, 9,10-dipropoxyanthracene, and 9,10-bis(2-ethylhexyloxy)anthracene; and thioxanthone sensitizers such as 2,4-diethylthioxanthone, 2-isopropylthioxanthone, and 4-isopropylthioxanthone can be mentioned. As representative examples of commercial products, anthracene sensitizers include DBA and DEA (manufactured by Kawasaki Chemical Industries, Ltd.), and thioxanthone sensitizers include DETX, ITX, and CPTX (manufactured by Lambson), and Omnipol TX (manufactured by IGM).

[0075] The content of the sensitizer is preferably 0 to 8.0% by mass relative to the total mass of the active energy ray-polymerizable component. Even if it exceeds 8.0% by mass, no improvement in effect is observed, and excessive addition is undesirable.

[0076] In addition, when a thioxanthone sensitizer is used as a sensitizer, since there is a tendency for the active energy ray-curable inkjet printing ink composition to turn yellow, the hue will become more yellow than the color based on pigments (original hue), so it is preferred to appropriately determine the content of the thioxanthone sensitizer for each color.

[0077] Specifically, it is preferred that a thioxanthone compound is not included as a sensitizer in a white ink composition and a transparent ink composition that are easily affected by a change in hue. In addition, since a magenta ink composition and a cyan ink composition may have a problem with a change in hue, it is preferred to use them within a range where there is no problem with the hue. In addition, a black ink composition and a yellow ink composition do not affect the hue even if there is a color change, and the active energy ray polymerizability is inferior to other hues, so it is preferred to use a thioxanthone compound as a sensitizer.

[0078] (Condition G)

[0079] As the condition G that can be adopted, the content of the (meth)acrylate monomer having a hydroxyl group is 0 to 25.0% by mass based on the total polymerizable components in the active energy ray-curable inkjet printing ink composition.

[0080] In the case other than white ink, the content of the (meth)acrylate monomer having a hydroxyl group is preferably 5.0 to 25.0% by mass, and more preferably 7.0 to 25.0% by mass, in the total polymerizable components in the active energy ray-curable inkjet printing ink composition. However, the active energy ray-curable inkjet printing ink composition may contain or not contain the (meth)acrylate monomer having a hydroxyl group.

[0081] In the case of white ink, the active energy ray-curable inkjet printing ink composition preferably does not contain a (meth)acrylate monomer having a hydroxyl group. The active energy ray-curable inkjet printing ink composition may contain a (meth)acrylate monomer having a hydroxyl group.

[0082] As the (meth)acrylate monomer having a hydroxyl group, one or more of the following monomers can be used.

[0083] Hydroxyalkyl (meth)acrylates such as 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, 3-hydroxybutyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, 6-hydroxyhexyl (meth)acrylate, and 8-hydroxyoctyl (meth)acrylate; polyethylene glycol mono(meth)acrylates such as diethylene glycol monoethyl ether (meth)acrylate, polypropylene glycol mono(meth)acrylate, and glycol mono(meth)acrylates such as 1,4-cyclohexanedimethanol mono(meth)acrylate; caprolactone-modified (meth)acrylates; hydroxyethyl acrylamide; and EO (ethylene oxide)-modified succinic acid (meth)acrylate.

[0084] Furthermore, a (meth)acrylate monomer having a hydroxyl group such as 4-hydroxybutyl (meth)acrylate having little odor is preferred.

[0085] <Condition H>

[0086] As the condition H that can be adopted, a vinyl monomer may be contained. The active energy ray-curable inkjet printing ink composition may contain 1.0 to 20.0% by mass of the vinyl monomer in the total polymerizable components. By containing the vinyl monomer, when printing on corrugated cardboard or the like, and the corrugated cardboard or the like is bent, the bending resistance can be further improved.

[0087] However, the active energy ray-curable inkjet printing ink composition may or may not contain a vinyl monomer.

[0088] The vinyl monomer is not particularly limited and can be, for example, ethylene glycol divinyl ether, triethylene glycol divinyl ether, diethylene glycol divinyl ether, 1,4-cyclohexanedimethanol divinyl ether, ethylene glycol monovinyl ether, propylene glycol divinyl ether, dipropylene glycol divinyl ether, butanediol divinyl ether, hexanediol divinyl ether, trimethylolpropane trivinyl ether, or the like.

[0089] Among them, the vinyl monomer is preferably triethylene glycol divinyl ether or the like which has little odor.

[0090] <Other polymerizable compounds>

[0091] In the present invention, in addition to the above-mentioned polymerizable components, other polymerizable compounds may be contained within a range in which performance is not deteriorated and within a range in which odor is reduced.

[0092] In the description of the following compounds, (poly) before the polyol portion means a condensate of mono- or di- or more polyols.

[0093] Benzyl methacrylate, butyl (meth)acrylate, ethyl carbitol (meth)acrylate, caprolactone (meth)acrylate, methoxytripropylene glycol (meth)acrylate, phenoxyethyl (meth)acrylate.

[0094] In addition, examples thereof include acryloylmorpholine, acrylonitrile, acrylamide, diethylacrylamide, styrene, (meth)acrylic acid, polyurethane (meth)acrylate, epoxy (meth)acrylate, polyester (meth)acrylate, pentaerythritol ethoxytetraacrylate, caprolactam-modified dipentaerythritol hexaacrylate, ethoxylated bisphenol A diacrylate, alkoxylated tetrahydrofurfuryl acrylate, dimethylol-tricyclodecane di(meth)acrylate, hydroxypivalic acid neopentyl glycol di(meth)acrylate, polytetramethylene glycol diacrylate, trimethylolpropane tri(meth)acrylate and its ethylene oxide modified product, pentaerythritol tri(meth)acrylate, and the like.

[0095] (Alkylene glycol di(meth)acrylate)

[0096] (Poly)alkylene glycol di(meth)acrylates such as ethylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, propylene glycol di(meth)acrylate, dipropylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate, tripropylene glycol di(meth)acrylate, 1,4-butylene glycol di(meth)acrylate, 1,5-propylene glycol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, 1,2-hexanediol di(meth)acrylate, 1,5-hexanediol di(meth)acrylate 1,2-decanediol di(meth)acrylate, 2-methyl-2-propyl-1,3-propanediol di(meth)acrylate, 2,4-dimethyl-2,4-pentanediol di(meth)acrylate, 2,2-diethyl-1,3-propanediol di(meth)acrylate, 2,5-hexanediol di(meth)acrylate, 1,7-heptanediol di(meth)acrylate, 1,8-octanediol di(meth)acrylate, 1,2-octanediol di(meth)acrylate, 1,9-nonanediol di(meth)acrylate, 1,2-decanediol di(meth)acrylate, 2-methyl-2-propyl-1,3-propanediol di(meth)acrylate, 2,4-dimethyl-2,4-pentanediol di(meth)acrylate, 2,2-diethyl-1,3-propanediol di(meth)acrylate ) acrylate, 2,2,4-trimethyl-1,3-pentanediol di(meth)acrylate, 1,12-dodecanediol di(meth)acrylate, 1,2-dodecanediol di(meth)acrylate, 1,14-tetradecanediol di(meth)acrylate, 1,2-tetradecanediol di(meth)acrylate, 1,16-hexadecanediol di(meth)acrylate, 1,2-hexadecanediol di(meth)acrylate, 2-methyl-2,4-pentanediol di(meth)acrylate, 3-methyl-1, 5-pentanediol di(meth)acrylate, dimethyloloctane di(meth)acrylate, 2-ethyl-1,3-hexanediol di(meth)acrylate, 2,5-dimethyl-2,5-hexanediol di(meth)acrylate, 2-methyl-1,8-octanediol di(meth)acrylate, 2-butyl-2-ethyl-1,3-propanediol di(meth)acrylate, 2,4-diethyl-1,5-pentanediol di(meth)acrylate, polyethylene glycol di(meth)acrylate, polypropylene glycol di(meth)acrylate.

[0097] ((Poly)glycerol poly(meth)acrylate)

[0098] Glyceryl di(meth)acrylate, glyceryl tetra(meth)acrylate, diglyceryl tetra(meth)acrylate.

[0099] ((Poly)trimethylolpropane poly(meth)acrylate)

[0100] Trimethylolpropane (meth)acrylate, trimethylolpropane di(meth)acrylate, trimethylolpropane tri(meth)acrylate, trimethylolpropane tetra(meth)acrylate, ditrimethylolpropane (meth)acrylate, ditrimethylolpropane di(meth)acrylate, ditrimethylolpropane tri(meth)acrylate, ditrimethylolpropane tetra(meth)acrylate.

[0101] ((Poly)pentaerythritol poly(meth)acrylate)

[0102] Pentaerythritol tetra(meth)acrylate and its ethylene oxide modified products, dipentaerythritol penta(meth)acrylate and its ethylene oxide modified products, dipentaerythritol hexa(meth)acrylate and its ethylene oxide modified products, tripentaerythritol hexa(meth)acrylate, tripentaerythritol hepta(meth)acrylate, tripentaerythritol octa(meth)acrylate, dipentaerythritol hexa(meth)acrylate.

[0103] (Other poly(meth)acrylates)

[0104] As the polyacrylate not included in the above, the following compounds can be used.

[0105] Monomers having four or more functions such as pentaerythritol tetracaprolactone tetra(meth)acrylate, ditrimethylolpropane tetracaprolactone tetra(meth)acrylate, ditrimethylolbutane tetra(meth)acrylate, ditrimethylolhexane tetra(meth)acrylate, ditrimethyloloctane tetra(meth)acrylate, and tripentaerythritol polyalkylene oxide hepta(meth)acrylate.

[0106] Hydroxypivaloyl hydroxypivalate di(meth)acrylate, hydroxypivaloyl hydroxypivalate dicaprolactone di(meth)acrylate, and the like.

[0107] Furthermore, 2-(2-vinyloxyethoxy)ethyl acrylate, 2-(allyloxymethyl)methyl acrylate, or an amide group-containing monomer may or may not be contained.

[0108] As resins other than the acrylic resins, for example, vinyl chloride resins, vinyl chloride-vinyl acetate resins and ethylene-vinyl acetate resins, styrene-acrylic resins, styrene-maleic acid resins, rosin resins, rosin ester resins, petroleum resins, coumarone resins, rosin phenol resins, phenolic resins, ketone resins, polyurethane resins, melamine resins, urea-formaldehyde resins, epoxy resins, cellulose resins, xylene resins, alkyd resins, aliphatic hydrocarbon resins, butyral resins, maleic acid resins, fumaric acid resins, etc. may be used in combination, within a range that does not reduce the performance of the active energy ray-curable ink jet printing ink composition of the present invention.

[0109] (Condition F)

[0110] As the colorant contained in the active energy ray-curable inkjet printing ink composition of the present invention, known pigments and dyes used in conventional active energy ray-curable inkjet printing ink compositions can be used, preferably pigments such as organic coloring pigments and inorganic coloring pigments. The ink composition of this embodiment preferably contains a colorant as component (I).

[0111] By containing a colorant, the ink composition can be made into an ink composition of various colors.

[0112] The organic coloring pigments include dye lake pigments, azo pigments, benzimidazolone pigments, phthalocyanine pigments, quinacridone pigments, anthraquinone pigments, dioxazines pigments, indigo pigments, thioindigo pigments, perylene pigments, perindole pigments, dione pyrrolopyrrole pigments, isoindolinone pigments, nitro pigments, nitroso pigments, flavonoid pigments, quinophthalone pigments, pyranthrone pigments, and indanthrone pigments.

[0113] Inorganic coloring pigments include colored pigments such as titanium oxide, red iron oxide, antimony red, cadmium yellow, cobalt blue, ultramarine, Prussian blue, iron black, chromium oxide green, carbon black, black lead, etc. (also including non-color coloring pigments such as white and black), and physical pigments such as calcium carbonate, kaolin, clay, barium sulfate, aluminum hydroxide, talc, etc.

[0114] Specific examples of the coloring pigments of each representative hue of the ink composition of the present invention are as follows. Yellow pigments include CI Pigment Yellow 1, 2, 3, 12, 13, 14, 16, 17, 42, 73, 74, 75, 81, 83, 87, 93, 95, 97, 98, 108, 109, 114, 120, 128, 129, 138, 139, 150, 151, 155, 166, 180, 184, 185, 213, etc., preferably CI Pigment Yellow 150, 155, 180, 213, etc.

[0115] Magenta pigments include CI Pigment Red 5, 7, 12, 19, 22, 38, 48:1, 48:2, 48:4, 49:1, 53:1, 57, 57:1, 63:1, 101, 102, 112, 122, 123, 144, 146, 149, 168, 177, 178, 179, 180, 184, 185, 190, 202, 209, 224, 242, 254, 255, 270, CI Pigment Violet 19, etc., preferably CI Pigment Red 122, 202, CI Pigment Violet 19, etc.

[0116] The cyan pigment is CI Pigment Blue 1, 2, 3, 15, 15:1, 15:2, 15:3, 15:4, 15:6, 16, 18, 22, 27, 29, 60, etc., preferably CI Pigment Blue 15:4, etc.

[0117] The black pigment is carbon black (CI Pigment Black 7) or the like.

[0118] The white pigment is titanium oxide, aluminum oxide, or the like, and titanium oxide or the like surface-treated with various materials such as aluminum oxide and silicon dioxide is preferred.

[0119] The content of the colorant is preferably 1% by mass or more in the ink composition, and is preferably 20% by mass or less in the ink composition. When the content of the colorant is within the above range, the image quality of the printed material obtained from the ink composition is appropriate and the viscosity characteristics are excellent.

[0120] (Pigment dispersant)

[0121] When the active energy ray-curable inkjet printing ink composition of the present invention contains a pigment, the pigment dispersant that may be contained is an ionic or nonionic surfactant, or an anionic, cationic or nonionic polymer compound.

[0122] Among them, preferred are polymer compounds, for example, carbodiimide compounds described in Japanese Patent Application Laid-Open No. 2004-083872, International Publication No. WO2003 / 076527, International Publication No. WO2004 / 000950, Ajisper PB821, 822 (manufactured by Ajinomoto Fine Technology Co., Ltd.) (acid value and amine value are both 10 to 20 mgKOH / g), SOLSPERSE 56000 (manufactured by LUBRIZOL), SOLSPERSE 32000 (manufactured by LUBRIZOL), SOLSPERSE 39000 (manufactured by LUBRIZOL), DISPERBYK (manufactured by BYK JAPAN), etc. These pigment dispersants can be used alone or in combination of two or more.

[0123] Among them, copolymers containing a basic functional group having an amine value of 10 to 40 mgKOH / g are preferred.

[0124] The pigment dispersant may be appropriately selected and used according to the type of the pigment and the type of the organic solvent used.

[0125] (Organic Solvent)

[0126] The active energy ray-curable inkjet printing ink composition of the present invention may be a so-called solvent-free type in which all liquid components are cured by a curing reaction, or a solvent-based type in which the printed coating is dried to remove the solvent and then cured. However, water is not used as a solvent.

[0127] Hereinafter, the case where the active energy ray-curable inkjet printing ink composition of the present invention contains an organic solvent will be described.

[0128] The organic solvent that may be contained in the active energy ray-curable inkjet printing ink composition of the present invention is propylene carbonate, diethylene glycol dialkyl ether, dipropylene glycol alkyl ether acetate, and the like.

[0129] As the diethylene glycol dialkyl ether, diethylene glycol ethyl methyl ether and / or diethylene glycol diethyl ether are preferably used, and other diethylene glycol dialkyl ethers may be used in combination.

[0130] As the dipropylene glycol alkyl ether acetate, those having an alkyl group with 6 or less carbon atoms are preferred, those having an alkyl group with 3 or less carbon atoms are more preferred, and those having an alkyl group with 2 or less carbon atoms are further preferred.

[0131] Furthermore, in order to adjust the drying properties and further improve the anti-spotting property, an alkylene glycol derivative having a flash point of 50 to 150° C. may be used in combination with diethylene glycol dialkyl ether.

[0132] Examples of such alkylene glycol derivatives having a flash point of 50 to 150° C. include (poly)ethylene glycol dialkyl ethers such as triethylene glycol dimethyl ether, triethylene glycol diethyl ether, and tetraethylene glycol dimethyl ether, (poly)propylene glycol dialkyl ethers such as propylene glycol dimethyl ether, propylene glycol diethyl ether, dipropylene glycol dimethyl ether, dipropylene glycol diethyl ether, tetrapropylene glycol diethyl ether, and tetrapropylene glycol dimethyl ether, (poly)propylene glycol monoalkyl ethers such as propylene glycol monobutyl ether, dipropylene glycol monomethyl ether, and dipropylene glycol monoethyl ether, (poly)propylene glycol monoalkyl ethers such as propylene glycol monoethyl ether acetate, propylene glycol monobutyl ether acetate, dipropylene glycol monomethyl ether acetate, dipropylene glycol monoethyl ether acetate, and dipropylene glycol monobutyl ether acetate, and (poly)propylene glycol monoalkyl ether monoalkyl esters such as ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, diethylene glycol monomethyl ether, and dipropylene glycol monoethyl ether. (Poly)ethylene glycol monoalkyl ethers such as methyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, triethylene glycol monomethyl ether, triethylene glycol monoethyl ether, triethylene glycol monobutyl ether and tetraethylene glycol monobutyl ether, (Poly)ethylene glycol monoalkyl ether monoalkyl esters such as ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, ethylene glycol monobutyl ether acetate, diethylene glycol monomethyl ether acetate and triethylene glycol monomethyl ether acetate, (Poly)ethylene glycol diesters such as ethylene glycol diacetate, diethylene glycol diacetate and triethylene glycol diacetate, (Poly)ethylene glycol monoether monoesters such as ethylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether acetate, diethylene glycol monobutyl ether acetate, diethylene glycol monopropyl ether acetate, triethylene glycol monomethyl ether, triethylene glycol monoethyl ether acetate and triethylene glycol monobutyl ether acetate, and the like.

[0133] Among the alkylene glycol derivatives having a flash point of 50 to 150° C., diethylene glycol ethyl methyl ether and diethylene glycol diethyl ether are mentioned first.

[0134] Furthermore, within the range that does not significantly change the flash point of the entire solvent, ethylene glycol diethyl ether, ethylene glycol dimethyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monomethyl ether acetate, etc., which have a flash point outside the range of 50 to 150°C, may be used in combination.

[0135] (Other ingredients)

[0136] Furthermore, the active energy ray-curable inkjet printing ink composition of the present invention may contain various additives such as surfactants, plasticizers, polymerization inhibitors, surface conditioners, UV inhibitors, light stabilizers, and antioxidants as needed.

[0137] (Viscosity of Active Energy Ray-Curable Inkjet Printing Ink Composition)

[0138] The viscosity of the active energy ray-curable inkjet printing ink composition of the present invention at 25° C. is preferably 30.0 mPa·s or less. If the viscosity exceeds 30.0 mPa·s, it may be difficult to discharge the ink composition from the inkjet printing nozzle.

[0139] The viscosity is measured at 25° C. and 20 rpm using an E-type viscometer (trade name: RE100L type viscometer, manufactured by Toki Sangyo Co., Ltd.).

[0140] (Manufacture of Active Energy Ray-Curable Inkjet Printing Ink Composition)

[0141] Next, a method for producing the active energy ray-curable inkjet printing ink composition of the present invention using these materials will be described.

[0142] The active energy ray-curable inkjet printing ink composition of the present invention can be obtained by, for example, dispersing and mixing using a disperser such as a wet circulation mill, a bead mill, a ball mill, a sand mill, an attritor, a roll mill, a DCP mill, a stirrer, a Henschel mixer, a colloid mill, an ultrasonic homogenizer, a high-pressure homogenizer (Micro fluidizer, Nanomizer, Ultimizer, GenusPY, DeBEE2000, etc.), or a pearl mill, and adjusting the viscosity of the active energy ray-curable inkjet printing ink composition to 2 to 10 mPa·s.

[0143] The total organic solvent content in the active energy ray-curable inkjet printing ink composition of the present invention is the amount obtained by deducting the total amount of each solid component and other additives used as needed from the total amount of the ink composition, and the ink viscosity is preferably appropriately changed so as to fall within the above range.

[0144] The active energy ray-curable inkjet printing ink composition of the present invention obtained as described above can be used on a paper substrate such as printing paper or corrugated cardboard paper using an inkjet printer.

[0145] (Method for producing printed matter)

[0146] Next, a method for producing a printed matter using the active energy ray-curable inkjet printing ink composition of the present invention will be described.

[0147] The production method includes the step of printing the active energy ray-curable inkjet printing ink composition on a substrate by an inkjet method.

[0148] The substrate is not particularly limited. For example, the substrate includes various resin substrates, paper, capsules, gels, metal foils, glass, wood, cloth and the like, and in particular, paper such as corrugated cardboard. After being printed on the substrate, the ink composition of this embodiment exhibits excellent bending resistance even when the substrate is bent. Therefore, the ink composition is particularly suitable for use when the substrate is a substrate for bending purposes such as corrugated cardboard.

[0149] When the substrate is a corrugated cardboard such as C cardboard (Jute liner) or K cardboard (kraft liner), the ink composition can be directly applied to the corrugated cardboard, or a pre-coat layer (primer layer) can be provided on the corrugated cardboard and then applied after corona discharge treatment. That is, in recent years, due to environmental considerations, corrugated cardboard sometimes uses old paper or recycled paper. When K cardboard is used as the corrugated cardboard, the surface is rough and the color is not bright, and the ink permeability during printing is high. Therefore, when the ink composition is printed on the corrugated cardboard,

[0150] Especially when the color of the substrate appears in the printed part, the inkjet image looks darker, which may damage the beauty of the printed material. For this kind of corrugated board, in order to solve the above-mentioned unevenness, etc., a pre-coating layer can be appropriately set.

[0151] The purpose of providing the pre-coat layer is to adjust the whiteness and color tone of the cardboard base paper constituting the corrugated cardboard and to improve the whiteness of the base, etc. The pre-coat layer can be formed by applying a pre-coat agent containing a pigment and a binder.

[0152] The pigment is not particularly limited. For example, the pigment may include, in addition to titanium dioxide (anatase, rutile), body pigments such as aluminum hydroxide, barium sulfate, calcium carbonate, amorphous silica, and clay. In addition, the content of the white pigment is preferably 20 to 85 parts by mass, more preferably 20 to 80 parts by mass, in 100 parts by mass of the pre-coat agent.

[0153] The binder resin used for the pre-coat layer of the corrugated board is preferably an aqueous resin. The aqueous resin is preferably a natural resin, a synthetic resin, etc., and more preferably a starch derivative, casein, shellac, a polyvinyl alcohol derivative, an acrylic acid and a maleic acid resin, etc. More specifically, the aqueous resin is suitable for using acrylic acid or methacrylic acid and its alkyl esters, or an aqueous acrylic resin, aqueous styrene-acrylic resin, aqueous styrene-maleic acid resin, aqueous styrene-acrylic acid-maleic acid resin, aqueous polyurethane resin, aqueous polyester resin, etc., which are copolymerized with styrene as the main monomer component. The content of the binder resin is preferably 1 to 25 parts by mass in 100 parts by mass of the pre-coating agent, and more preferably 1 to 15 parts by mass.

[0154] The aqueous medium that can be used in the pre-coat layer (primer layer) can be water or a mixture of water and a water-miscible solvent. The water-miscible solvent includes lower alcohols, polyols and their alkyl ethers or alkyl esters. Specifically, the water-miscible solvent includes lower alcohols such as methanol, ethanol, n-propanol, isopropanol, ethylene glycol, propylene glycol, diethylene glycol, dipropylene glycol, glycerol and the like, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monoacetate, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monoacetate, diethylene glycol monomethyl ether, dipropylene glycol monomethyl ether and the like.

[0155] In addition to the above-mentioned components, the pre-coat layer may also contain various additives such as film formers, pigment dispersants or pigment dispersing resins, anti-caking agents, wetting agents, viscosity regulators, pH regulators, defoaming agents, general surfactants, etc., as appropriate.

[0156] The method for producing the pre-coat agent using the above-mentioned various materials is not particularly limited. For example, the method for producing the pre-coat agent includes a general method as follows: a white pigment, an aqueous binder resin, water, a water-miscible solvent as required, and a pigment dispersant or a pigment dispersion resin are mixed and kneaded, and an additive, water, a water-miscible solvent as required, and the remainder of the prescribed material are further added and mixed.

[0157] The pre-coat agent can be easily obtained by mixing the required amounts of the above-mentioned components and mixing and dispersing them using a high-speed stirrer such as a homomixer or a laboratory mixer or a disperser such as a three-roll mill or a bead mill.

[0158] When a primer layer is provided, the thickness of the primer layer (the amount of the pre-coating agent applied) is not particularly limited. The primer layer preferably has a solid content applied amount of 0.1 to 5 g / m 2 By keeping the thickness of the primer layer (the amount of the pre-coating agent applied) within the above range, it is easy to appropriately adjust the whiteness or color tone of the corrugated cardboard.

[0159] Specific examples of the printing and curing methods of the active energy ray-curable inkjet printing ink composition of the present invention include a method in which the active energy ray-curable inkjet printing ink composition of the present invention is ejected onto a substrate through an inkjet head, and then the coating film of the ink composition of the present invention deposited on the substrate is exposed to light to cure the ink composition.

[0160] For example, the ejection onto the substrate (printing of the image) can be performed by providing the active energy ray-curable inkjet printing ink composition of the present invention to a low viscosity corresponding print head of an inkjet recording printer, and ejecting the ink composition from the print head in such a manner that the film thickness of the coating on the substrate reaches, for example, 1 to 60 μm. In addition, light exposure and curing (curing of the image) can be performed by irradiating the coating of the active energy ray-curable inkjet printing ink composition of the present invention applied as an image on the substrate with active energy rays.

[0161] As the inkjet printing device for printing the active energy ray-curable inkjet printing ink composition of the present invention, a conventionally used inkjet printing device can be used. In addition, when a continuous inkjet printing device is used, a conductive agent is further added to the active energy ray-curable inkjet printing ink composition of the present invention to adjust the conductivity.

[0162] As the active energy ray source during the curing of the above-mentioned coating film, ultraviolet rays (UV lamp), ultraviolet rays (light emitting diode (LED)), electron rays, visible rays, etc. can be listed. As a specific device, for example, one or more selected from ultra-high pressure mercury lamps, high pressure mercury lamps, low pressure mercury lamps, mercury xenon lamps, metal halide lamps, high power metal halide lamps, xenon lamps, pulsed light emitting xenon lamps, deuterium lamps, fluorescent lamps, Nd-YAG 3-fold frequency lasers, He-Cd lasers, nitrogen lasers, Xe-Cl excimer lasers, Xe-F excimer lasers, semiconductor excitation solid lasers, LED lamps, etc. can be used. From an environmental perspective, it is preferably a light emitting diode (LED) that generates ultraviolet rays with a luminescence peak wavelength in the range of 350 to 420 nm.

[0163] Ultraviolet light using a light emitting diode (LED) as a light source refers to “light irradiated from a light emitting diode that generates ultraviolet light with a peak emission wavelength in the range of 350 to 420 nm”.

[0164] The temperature of the ink composition during printing may be room temperature, which is approximately 20 to 26° C., or another temperature.

[0165] Example

[0166] The present invention is further described in detail by way of examples below, but the present invention is not limited to these examples. In addition, unless otherwise specified, "%" means "mass %" and "parts" means "mass parts".

[0167] The materials used in the following examples and comparative examples are as follows: The unit of the numerical values ​​in the columns of pigment, dispersant, resin, solvent and total in the table is "mass %".

[0168] (pigment)

[0169] PB15:4: Pigment Blue 15:4

[0170] Titanium oxide

[0171] CN371 (manufactured by Sartomer) (amine-modified oligomer)

[0172] EOTMPTA: Ethoxytrimethylolpropane triacrylate (photopolymerizable compound containing an alkoxy group)

[0173] HDDA: 1,6-Hexanediol diacrylate

[0174] LA: Lauryl acrylate

[0175] STA: Stearyl Acrylate

[0176] 4HBA: 4-Hydroxybutyl Acrylate

[0177] (Photopolymerization Initiator)

[0178] TPO: 2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide

[0179] Irgacure819: Bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide

[0180] TPOL: Ethoxy(2,4,6-trimethylbenzoyl)phenylphosphine oxide

[0181] Esacure ONE: Oligo{2-hydroxy-2-methyl-1-[4-(1-methylvinyl)phenyl]propanone}

[0182] KIP160: 2-Hydroxy-1-{4-[4-(2-hydroxy-2-methylpropionyl)phenoxy]phenyl}-2-methylpropanone

[0183] (Sensitizer)

[0184] DETX: diethylthioxanthone (produced by Lambson)

[0185] TX1: Omnipol TX (manufactured by IGM)

[0186] (Inhibitor)

[0187] UV-5

[0188] (Surface Conditioner)

[0189] BYK-331: silicone surfactant

[0190] (Pigment dispersant)

[0191] PB822 (manufactured by Ajinomoto Fine Technologies Co., Ltd.)

[0192] (Examples 1 to 12, Comparative Examples 1 to 8)

[0193] <Production of Active Energy Ray-Curable Inkjet Printing Ink Composition>

[0194] According to the formulation in Table 1, active energy ray-curable inkjet printing ink compositions of Examples and Comparative Examples were obtained.

[0195] <Corrugated cardboard base material>

[0196] K paperboard, C paperboard

[0197] <Pre-coat>

[0198] 45 parts by mass of calcium carbonate with an average particle size of 0.05 μm, 25 parts by mass of styrene-maleic acid resin (solid content 25%) with an acid value of 170 mgKOH / g, and 30 parts by mass of water were dispersed with a bead mill to obtain a 45% slurry of calcium carbonate. 80 parts by mass of 45% slurry of calcium carbonate and 20 parts by mass of styrene-maleic acid resin (solid content 25%) with an acid value of 170 mgKOH / g were mixed and stirred to obtain a pre-coating agent.

[0199] <Applying pre-coating agent to K paperboard>

[0200] Use a 0.1 mm Mayer bar to achieve a coating amount of about 4 g / m 2 The pre-coating agent prepared as described above is applied to the K paperboard in a coating amount of . Next, the pre-coating agent-coated surface is dried by hot air drying.

[0201] <Evaluation Method and Evaluation Criteria>

[0202] The evaluation criteria described in Table 1 are as follows.

[0203] (Viscosity)

[0204] The viscosity of the active energy ray-curable inkjet printing ink compositions obtained in Examples and Comparative Examples was measured using an E-type viscometer (trade name: RE100L viscometer, manufactured by Toki Sangyo Co., Ltd.) at a temperature of 25° C. and a rotor speed of 20 rpm.

[0205] (Coating odor)

[0206] After forming a coating film on the substrate in a size of 8 cm x 12 cm and curing it, the substrate was placed in a 24 cm x 34 cm zipper bag and the odor inside the bag was checked after one hour. Ten people were asked to smell it and evaluate it using the following five levels. The average value of the ten people is rounded off to the nearest decimal point in the table.

[0207] 5: Odorless

[0208] 4: Low odor

[0209] 3: Medium odor

[0210] 2: Strong odor

[0211] 1: Strong odor

[0212] (Curing property)

[0213] The inkjet recording device and the active energy ray-curable inkjet printing ink composition were left at an ambient temperature of 25° C. for 24 hours to allow the temperature of the inkjet recording device and the active energy ray-curable inkjet printing ink composition to reach 25° C. Then, the active energy ray-curable inkjet printing ink composition was continuously printed (printed) on K paperboard and C paperboard coated with a pre-coating agent at 25° C., and then the UV-LED light lamp manufactured by Phoseon Technology was used at a distance of 2 cm between the lamp and the ink coating surface at a UV cumulative light dose of 180 mJ / cm 2 The obtained curable coating film was rubbed with a cotton swab, and the curability was evaluated based on the degree of peeling according to the following evaluation criteria.

[0214] ○: No peeling.

[0215] △: There is some peeling.

[0216] ×: There is peeling.

[0217] (Adhesion)

[0218] The inkjet printing (recording) device equipped with an inkjet nozzle for low-viscosity ink and each ink composition were left at an ambient temperature of 25° C. for 24 hours to allow the temperature of the inkjet printing device and each ink composition to reach 25° C. Then, each ink composition was continuously printed (printed) on PVC80 (vinyl chloride resin sheet (12 cm×18 cm), manufactured by LINTEC) at 25° C., and then UV-LED light lamp manufactured by Phoseon Technology was used at a distance of 2 cm between the lamp and the ink coating surface at a UV cumulative light dose of 180 mJ / cm 2 The coating film surface was touched with a finger, and the state of the coating film after touching was visually confirmed to evaluate the adhesiveness.

[0219] ○: No fingerprints adhere to the coating film.

[0220] △: There are a few fingerprints on the coating film.

[0221] ×: Fingerprints adhere to the coating film.

[0222] (Bending resistance)

[0223] The ink composition was printed on K paperboard or C paperboard coated with a precoat agent, and the paperboard was folded 90 degrees with the printed surface facing outward (with the backs of the non-printed surfaces of the K paperboard and C paperboard facing each other), and evaluated according to the following evaluation criteria.

[0224] ○: No linear cracks or fine cracks were generated in the coating film when it was bent.

[0225] △: Micro cracks occurred when bending.

[0226] ×: Linear cracks occurred when the sample was bent.

[0227] (Abrasion resistance)

[0228] The cured film obtained in the evaluation of curability was rubbed 200 times with a bleached cloth soaked in water at 500 g using a Gakushin type fastness tester (manufactured by Daiei Kagaku Seiki Mfg. Co., Ltd.), and peeling of the cured film from the K paper board and C paper board coated with the pre-coating agent was visually observed, and evaluation was performed according to the following evaluation criteria.

[0229] ○: There is no peeling of the cured film.

[0230] △: The surface of the cured film has scratches.

[0231] ×: The cured film peeled off and the sheet was visible.

[0232] (Water resistance)

[0233] The cured film obtained in the evaluation of curability was rubbed with a bleached cloth soaked in water at a weight of 500 g for 30 times using a Gakushin type fastness tester (manufactured by Daiei Kagaku Seiki Mfg. Co., Ltd.), and peeling of the cured film from the K paper board and C paper board coated with the pre-coating agent was visually observed, and evaluation was performed according to the following evaluation criteria.

[0234] ○: There is no peeling of the cured film.

[0235] △: The surface of the cured film has scratches.

[0236] ×: The cured film peeled off and the sheet was visible.

[0237] [Table 1]

[0238]

[0239]

[0240] According to the examples of the present invention, that is, according to each embodiment, an active energy ray-curable ink composition for inkjet printing can be obtained, which has low viscosity, no odor in the coating film, excellent curability, no tackiness in the cured coating film, and excellent bending resistance, friction resistance and water resistance.

[0241] In contrast, according to Comparative Example 1 which does not contain ESACURE ONE and KIP160, the coating film has an odor, and is inferior in curability, adhesion, adhesion to some substrates, abrasion resistance, and water resistance. Similarly, according to Comparative Example 2 which does not contain ESACURE ONE and KIP160 and has a large total content of Irgacure 819 and TPOL, adhesion and abrasion resistance are inferior.

[0242] In addition, according to Comparative Example 3 in which the total content of TPOL is small, the coating film has odor, and the curing property, adhesion, friction resistance and water resistance are poor. According to Comparative Example 4 which does not contain amine-modified oligomers, the coating film has odor, and the curing property, adhesion, bending resistance and friction resistance are poor. According to Comparative Example 5 in which the content of the compound under Condition D is small, the coating film has odor, and the curing property, adhesion, friction resistance and water resistance are poor.

[0243] Furthermore, according to Comparative Example 6 which does not contain the compound of Condition C and does not contain a (meth)acrylate monomer having an alkyl group with 6 to 20 carbon atoms, the bending resistance is poor. According to Comparative Example 7 which contains the component of Condition D in excess, the coating film has an odor, and the curing property, adhesion, bending resistance and abrasion resistance are poor. Furthermore, according to Comparative Example 8 which contains the compound of Condition C in excess, the coating film has an odor, and the curing property, adhesion and abrasion resistance are poor.

Claims

1. An active energy ray-curable inkjet printing ink composition, characterized in that: Satisfy the following conditions A~E: The content of (A) the amine-modified oligomer in the active energy ray-curable inkjet printing ink composition is 1.0 to 20.0% by mass; (B) the active energy ray-curable inkjet printing ink composition contains 2.0 to 20.0% by mass of a (meth)acrylate monomer having an alkoxy group; (C) an active energy ray-curable inkjet printing ink composition containing 2.0 to 25.0% by mass of a (meth)acrylate monomer having an alkyl group having 6 to 20 carbon atoms; (D) an active energy ray-curable inkjet printing ink composition containing 30.0 to 60.0% by mass of at least one selected from 1,6-hexanediol diacrylate, 3-methyl-1,5-pentanediol diacrylate, dipropylene glycol diacrylate, 1,10-decanediol diacrylate, propoxylated (2) neopentyl glycol diacrylate, and hydroxypivalate neopentyl glycol diacrylate; (E) The active energy ray-curable inkjet printing ink composition contains 3.0 to 15.0% by mass of ethoxy(2,4,6-trimethylbenzoyl)phenylphosphine oxide as a photopolymerization initiator, and the active energy ray-curable inkjet printing ink composition contains 2.0 to 10.0% by mass of oligo(2-hydroxy-2-methyl-1-(4-(1-methylvinyl)phenyl)propanone) and / or 2-hydroxy-1-{4-〔4-(2-hydroxy-2-methylpropanoyl)phenoxy]phenyl}-2-methylpropanone, and the total content of the photopolymerization initiator is 6.0 to 25.0% by mass in the active energy ray-curable inkjet printing ink composition.

2. The active energy ray-curable inkjet printing ink composition according to claim 1, wherein At least a part of the (meth)acrylate monomers having an alkoxy group in (B) is a polyfunctional (meth)acrylate monomer, and the active energy ray-curable inkjet printing ink composition contains 5.0 to 20.0% by mass of the polyfunctional (meth)acrylate monomer.

3. The active energy ray-curable inkjet printing ink composition according to claim 1 or 2, wherein: The (meth)acrylate monomer having an alkyl group having 6 to 20 carbon atoms includes one or two selected from lauryl acrylate and stearyl acrylate.

4. The active energy ray-curable inkjet printing ink composition according to claim 1 or 2, wherein: One of the (meth)acrylate monomers having an alkyl group having 10 to 20 carbon atoms is lauryl acrylate synthesized using a plant-derived compound.

5. The active energy ray-curable inkjet printing ink composition according to claim 1 or 2, wherein: 1,10-Decanediol diacrylate is a substance synthesized using a plant-derived compound.

6. The active energy ray-curable ink composition for inkjet printing according to claim 1 or 2, wherein: Contains (F) colorant.

Images