JPH08143806A - Composition for ink curable by actinic ray - Google Patents

Abstract

PURPOSE: To obtain the subject composition composed of a compound having oxetane ring, a cationic photopolymerization initiator and a pigment, having excellent curability and various printing properties such as fluidity, pigment dispersibility and low misting tendency, etc., and useful for various printing methods. CONSTITUTION: This composition contains (A) a compound having 1-4 oxetane rings e.g. a compound of formula I (R<1> is H, a 1-6C alkyl, allyl, etc.; R<2> is a 1-6C alkyl, a 2-6C alkenyl, phenyl, a group having aromatic ring such as benzyl, etc.), a compound of formula II [R<3> is a lxnear or branched alkylene, a poly(alkylenoxy), etc.] or a compound of formula III (R<9> is a 1-12C branched alkylene, branched polysiloxy, etc.; (j) is 3 or 4), (B) a cationic photopolymerization initiator (preferably diaryliodonium salt or triarylsulfonium salt) and (C) a pigment. The composition is preferably further incorporated with a compound containing epoxy group, a compound containing vinyl ether group, etc.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an active energy ray-curable ink composition comprising a compound having an oxetane ring, and is used in the field of producing and using ink. In addition, in this specification, an acryloyl group or a methacryloyl group is represented as a (meth) acryloyl group.

[0002]

2. Description of the Related Art Conventionally, a printing ink in which a resin is dissolved in an organic solvent has been used. For example, as an ink used in offset printing, there is a so-called high viscosity ink including a varnish obtained by dissolving a rosin phenolic resin, a rosin maleic acid resin or an oil-modified alkyd resin in a high boiling point petroleum solvent. However, such an organic solvent-based ink has a slow drying property and is inferior in abrasion resistance and solvent resistance of the printed matter,
When it is used as an ink, it requires forced drying, which requires a drying facility, and requires a large amount of energy for drying, which is disadvantageous in that it requires a great deal of cost. . As an ink composition that solves these problems, active energy ray-curable ink compositions have come to be used. The active energy ray-curable ink composition has many advantages such as no environmental pollution because it is essentially solvent-free, and does not require forced drying because it does not require forced drying. It is a thing.

[0003]

The majority of conventional active energy ray-curable ink compositions are concentrated in polyfunctional acrylates and unsaturated polyesters which are cured by active energy ray-initiated radical polymerization. Even today, these compounds are still used in large quantities. However, when these compounds are used as a composition for active energy ray-curable ink, the viscosity of the composition may be too high to be used, and the curability and surface hardness are not impaired. There was no one satisfying all the printability such as fluidity, pigment dispersibility and misting. As an active energy ray curing technique other than the active energy ray initiated radical polymerization, an active energy ray initiated ionic polymerization technique has been put into practical use. In particular, active energy ray-initiated cationic polymerization is
Since the polymerization is not hindered by oxygen, there is no particular limitation that it must be carried out under an inert atmosphere, and it has the advantage that rapid and complete polymerization can be carried out in air. To date, the development of active energy ray initiated cationic polymerization technology has focused on two types of monomers: epoxy resins and vinyl ethers. In particular, the photocurable epoxy resin has excellent adhesiveness, and the cured film has good heat resistance and chemical resistance. However, the conventional photocurable epoxy resin has a defect that the photopolymerization rate is relatively slow, and thus cannot be used in applications where rapid photocuring is required. or,
Low-molecular-weight photocurable epoxy resins have been pointed out to have toxicity such as mutagenicity, and their danger has been a problem. On the other hand, many photo-curable vinyl ethers are volatile and have a strong odor, and many of them have shrinkage upon curing as compared with photo-curable epoxy. The present inventors have solved these problems and are excellent in printability and curability such as fluidity, pigment dispersibility and misting, and the cured film thereof is an active energy ray curable ink excellent in surface hardness and solvent resistance. The inventors have made diligent studies to find a composition for use.

[0004]

Means for Solving the Problems The inventors of the present invention have made various investigations to solve the above problems as a composition for an active energy ray-curable ink, in which a composition comprising a cyclic ether having a specific structure is used. The present invention has been completed by finding that the above can be achieved. That is, the first invention of the present invention is a composition for an active energy ray-curable ink comprising a compound having 1 to 4 oxetane rings, a cationic photopolymerization initiator and a pigment, and a second invention is a compound having an epoxy group. The composition for active energy ray-curable ink of the first invention further contains, the composition for active energy ray-curable ink of the first invention further contains a compound having a vinyl ether group, and the fourth invention is ) The active energy ray-curable ink composition of the first invention, which further comprises a compound having an acryloyl group and a photoradical polymerization initiator. Hereinafter, the present invention will be described in detail.

Compound Having 1 to 4 Oxetane Rings The compound having an oxetane ring used in the present invention has 1 to 4 oxetane rings. When a compound having 5 or more oxetane rings is used, the fluidity of the composition may be lost and the composition may not be suitable for printing. The compound having an oxetane ring used in the present invention has 1 to 4 oxetane rings.
Various compounds can be used as long as they have individual compounds. 1
Specific examples of the compound having one oxetane ring include compounds represented by the following general formula (1).

[0006]

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In the formula (1), R ¹ is a hydrogen atom, an alkyl group having 1 to 6 carbon atoms such as a methyl group, an ethyl group, a propyl group or a butyl group, a fluoroalkyl group having 1 to 6 carbon atoms, It is an allyl group, an aryl group, a furyl group or a thienyl group. R ² is an alkyl group having 1 to 6 carbon atoms such as a methyl group, an ethyl group, a propyl group or a butyl group, 1-
Alkenyl having 2 to 6 carbon atoms such as propenyl group, 2-propenyl group, 2-methyl-1-propenyl group, 2-methyl-2-propenyl group, 1-butenyl group, 2-butenyl group or 3-butenyl group. Group, phenyl group, benzyl group,
A group having an aromatic ring such as fluorobenzyl group, methoxybenzyl group or phenoxyethyl group, alkylcarbonyl group having 2 to 6 carbon atoms such as ethylcarbonyl group, propylcarbonyl group or butylcarbonyl group, ethoxycarbonyl group, propoxycarbonyl group Alternatively, it is an alkoxycarbonyl group having 2 to 6 carbon atoms such as butoxycarbonyl group, or an N-alkylcarbamoyl group having 2 to 6 carbon atoms such as ethylcarbamoyl group, propylcarbamoyl group, butylcarbamoyl group or pentylcarbamoyl group. .

Next, examples of the compound having two oxetane rings include compounds represented by the following general formula (2).

[0009]

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In the formula (2), R ¹ is the same group as in the general formula (1). R ³ is, for example, a linear or branched alkylene group such as ethylene group, propylene group or butylene group, poly (ethyleneoxy)
Group or a linear or branched poly (alkyleneoxy) group such as a poly (propyleneoxy) group, a propenylene group, a linear or branched unsaturated hydrocarbon group such as a methylpropenylene group or a butenylene group, a carbonyl group, An alkylene group containing a carbonyl group, an alkylene group containing a carboxyl group, an alkylene group containing a carbamoyl group, and the like.
R ³ is also a polyvalent group selected from the groups represented by the following formulas (3), (4) and (5).

[0011]

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In the formula (3), R ⁴ is a hydrogen atom, an alkyl group having 1 to 4 carbon atoms such as a methyl group, an ethyl group, a propyl group or a butyl group, a methoxy group, an ethoxy group, a propoxy group or a butoxy group. An alkoxy group having 1 to 4 carbon atoms such as, a halogen atom such as a chlorine atom or a bromine atom,
It is a nitro group, a cyano group, a mercapto group, a lower alkylcarboxyl group, a carboxyl group, or a carbamoyl group.

[0013]

[Chemical 4]

In the formula (4), R ⁵ is an oxygen atom, a sulfur atom, a methylene group, NH, SO, SO ₂ , C (C
F ₃ ) ₂ or C (CH ₃ ) ₂ .

[0015]

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In the formula (5), R ⁶ is an alkyl group having 1 to 4 carbon atoms such as a methyl group, an ethyl group, a propyl group or a butyl group, or an aryl group. n is 0 to 20
00 is an integer. R ⁷ is an alkyl group having 1 to 4 carbon atoms such as methyl group, ethyl group, propyl group or butyl group,
Or, it is an aryl group. R ⁷ is also a polyvalent group selected from the groups represented by the following formula (6).

[0017]

[Chemical 6]

In the formula (6), R ⁸ is an alkyl group having 1 to 4 carbon atoms such as a methyl group, an ethyl group, a propyl group and a butyl group, or an aryl group. m is 0 to 100
Is an integer. Specific examples of the compound having two oxetane rings include compounds represented by the following formulas (7) and (8).

[0019]

[Chemical 7]

The compound represented by the formula (7) is a compound of the formula (2) in which R ¹ is an ethyl group and R ³ is a carboxyl group.

[0021]

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The compound represented by the formula (8) is a compound represented by the general formula (2), wherein R ¹ is an ethyl group and R ³ is R in the formula (5)
^A compound in which ⁶ and R ⁷ are methyl groups and n is 1.

Among the compounds having two oxetane rings, preferred examples other than the above compounds include compounds represented by the following general formula (9).

[0024]

[Chemical 9]

Examples of the compound having 3 to 4 oxetane rings include compounds represented by the following general formula (10).

[0026]

[Chemical 10]

In the formula (10), R ¹ is the same group as in the general formula (1). R ⁹ represents, for example, a group represented by the following formulas (11) to (13) having 1 to 1 carbon atoms.
And 12 branched alkylene groups, branched poly (alkyleneoxy) groups such as the group represented by the following formula (14), branched polysiloxy groups such as the group represented by the following formula (15), and the like. . j is 3 or 4.

[0028]

[Chemical 11]

[In the formula (11), R ¹⁰ is a methyl group,
A lower alkyl group such as an ethyl group or a propyl group. ]

[0030]

[Chemical 12]

[0031]

[Chemical 13]

[0032]

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[In the formula (14), l is an integer of 1 to 10. ]

[0034]

[Chemical 15]

Specific examples of the compound having 3 to 4 oxetane rings include a compound represented by the following formula (16).

[0036]

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Further, as an example of the compound having 1 to 4 oxetane rings other than the above, there is a compound represented by the following formula (17).

[0038]

[Chemical 17]

In the formula (17), R ⁸ is the same group as in the formula (6). R ¹¹ is an alkyl group having 1 to 4 carbon atoms such as a methyl group, an ethyl group, a propyl group or a butyl group, or a trialkylsilyl group, and r is 1 to 4.

More preferred examples of the oxetane compound used in the present invention include the compounds shown below.

[0041]

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[0042]

[Chemical 19]

[0043]

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[0044]

[Chemical 21]

In addition to these, the molecular weight is from 1000 to 5
A compound having a high molecular weight of about 000 and having 1 to 4 oxetane rings is also included. Examples of these include the following compounds.

[0046]

[Chemical formula 22] Here, p is 20 to 200.

[0047]

[Chemical formula 23] Here, q is 15 to 100.

[0048]

[Chemical formula 24] Here, s is 20 to 200.

Photocationic Polymerization Initiator As the photocationic polymerization initiator used in the composition of the present invention, various kinds can be used. Preferred examples of these initiators include diaryliodonium salts and triarylsulfonium salts. A typical cationic photopolymerization initiator is shown below.

[0050]

[Chemical 25]

[0051]

[Chemical formula 26]

[0052]

[Chemical 27]

[0053]

[Chemical 28]

In the formula, R ¹² is a hydrogen atom and has 1 to 18 carbon atoms.
Or an alkoxy group having 1 to 18 carbon atoms, R ¹³ is a hydrogen atom, a hydroxyalkyl group or a hydroxyalkoxy group, and preferably a hydroxyethoxy group. M is a metal, preferably antimony,
X is halogen, preferably fluorine, and k is the valence of the metal, for example 5 in the case of antimony. The cationic photopolymerization initiator is preferably contained in the compound having an oxetane ring in a proportion of 0.1 to 20% by weight, more preferably 0.1 to 10% by weight. When the composition of the first invention further contains a compound having an epoxy group and / or a compound having a vinyl ether group, which will be described later, a compound having an oxetane ring, a compound having an epoxy group and / or a compound having a vinyl ether group can be used. The content is preferably 0.1 to 20% by weight, more preferably 0.1 to 10% by weight, based on the total amount. If the amount is less than 0.1% by weight, the curability is not sufficient. On the other hand, if the amount exceeds 20% by weight, the light transmittance is poor and uniform curing cannot be performed or the coating surface is not smooth. The sex may be lost.

Pigment As the pigment of the essential component of the invention, various pigments such as organic pigments and / or inorganic pigments can be used. Specifically, white pigments such as titanium oxide, zinc white, lead white, lithobon and antimony oxide, black pigments such as aniline black, iron black and carbon black, yellow lead, yellow iron oxide, Hansa Yellow (100, 50, 30 etc.), yellow pigments such as titanium yellow, benzine yellow and permanent yellow, orange pigments such as chrome vermilion, permanent orange, balkan first orange and indanthrene brilliant orange, iron oxide, brown such as permanent brown and para brown. Pigment, red iron oxide, cadmium red, antimony vermillion, permanent red, rhodamine lake, alizarin lake, thioindigo red, PV
Red pigments such as carmine, monolite fast red and quinacridone red pigments, cobalt purple, manganese purple,
First violet, methyl violet rake,
Purple pigments such as indanthrene brilliant violet and dioxazine violet, ultramarine blue, navy blue, cobalt blue, alkali blue lake, metal-free phthalocyanine blue, copper phthalocyanine blue, blue pigments such as indanthrene blue and indigo, chrome green, chromium oxide In addition to green pigments such as, emerald green, naphthol green, green gold, acid green lake, malachite green lake, phthalocyanine green and polychlorobrom copper phthalocyanine, various fluorescent pigments, metal powder pigments, extender pigments and the like can be mentioned. The content of the pigment is preferably 1 to 100 parts by weight, more preferably 10 parts by weight, based on 100 parts by weight of the compound having an oxetane ring.
˜50 parts by weight. When the compound having an epoxy group, the compound having a vinyl ether group and / or the compound having a (meth) acryloyl group described below is added to the compound having an oxetane ring, the total amount of these curable components is 100% by weight. The content of the pigment is preferably 1 to 100 parts by weight, more preferably 10 to 5 parts by weight.
0 parts by weight. When the content of the pigment is less than 1 part by weight based on 100 parts by weight of the curable component, it is difficult to color the composition, and when it exceeds 100 parts by weight, the curability of the composition may be poor.

Other Compounds In addition to the above-mentioned essential components, other components can be blended in the composition of the present invention as required. A second invention of the present invention is an active energy ray-curable ink composition, which further comprises a compound having an epoxy group in the composition of the first invention. In this case, by including an epoxy compound in the composition, the curing rate of the composition can be further improved. Various compounds can be used as the compound having an epoxy group. For example, 1 epoxy group
As the epoxy compound having one, there are phenylglycidyl ether and butylglycidyl ether, and as the epoxy compound having two or more epoxy groups, hexanediol diglycidyl ether, tetraethylene glycol diglycidyl ether, trimethylolpropane triglycidyl ether, Examples thereof include bisphenol A diglycidyl ether and novolac type epoxy compounds. Particularly in the present invention, it is preferable to use an alicyclic epoxy compound, and examples thereof include the compounds shown below.

[0057]

[Chemical 29]

[0058]

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[0059]

[Chemical 31]

In this case, the compounding ratio of the compound having an epoxy group is 5 to 95 parts by weight based on 100 parts by weight of the total amount of the compound having 1 to 4 oxetane rings and the compound having an epoxy group. preferable.

A third invention of the present invention is an active energy ray-curable ink composition, which further comprises a compound having a vinyl ether group in the composition of the first invention. In this case, by including the compound having a vinyl ether group in the composition, the curing rate of the composition can be further improved. Various compounds can be used as the compound having a vinyl ether group. For example, examples of the compound having one vinyl ether group include hydroxyethyl vinyl ether, hydroxybutyl vinyl ether, dodecyl vinyl ether, propenyl ether propylene carbonate and cyclohexyl vinyl ether. Examples of the compound having two or more vinyl ether groups include cyclohexanedimethanol divinyl ether, triethylene glycol divinyl ether, and novolak type divinyl ether. In this case, the compounding ratio of the compound having a vinyl ether group is 1
5 to 5 parts by weight based on 100 parts by weight of the total amount of the compound having 4 oxetane rings and the compound having a vinyl ether group.
95 parts by weight is preferred.

A fourth invention of the present invention is an active energy ray-curable ink composition, which further comprises a compound having a (meth) acryloyl group and a photoradical polymerization initiator in the composition of the first invention. In this case, by including a compound having a (meth) acryloyl group in the composition, the composition viscosity can be adjusted and the coating film hardness of the composition can be modified. Various compounds can be used as the compound having a (meth) acryloyl group. For example, (meta)
Examples of the compound having one acryloyl group include (meth) acrylates of phenol, nonylphenol and 2-ethylhexanol, and (meth) acrylates of alkylene oxide adducts of these alcohols. Examples of the compound having two (meth) acryloyl groups include bisphenol A, isocyanuric acid, di (meth) acrylate of ethylene glycol and propylene glycol, and di (meth) acrylate of an alkylene oxide adduct of these alcohols. . Examples of compounds having three (meth) acryloyl groups include penta (erythritol), tri (meth) acrylate of trimethylolpropane and isocyanuric acid, and tri (meth) acrylate of an alkylene oxide adduct of these alcohols. Examples of the compound having four or more acryloyl groups include pentaerythritol and poly (meth) acrylate of dipentaerythritol. Further, conventionally known acrylic-based monomers / oligomers such as urethane acrylate having a urethane bond as a main chain, polyester acrylate having an ester bond as a main chain, and epoxy (meth) acrylate obtained by adding acrylic acid to an epoxy compound are also included. In this case, as the compounding ratio of the compound having a (meth) acryloyl group, the total amount of the compound having 1 to 4 oxetane rings and the compound having a (meth) acryloyl group is 1
5 to 95 parts by weight is preferable with respect to 00 parts by weight. In the fourth aspect of the present invention, a photoradical polymerization initiator is added to the composition. As the photo-radical polymerization initiator, various ones can be used, and preferred ones are benzophenone and its derivatives, benzoin alkyl ether, and 2-methyl [4- (methylthio) phenyl] -2-.
Morpholino-1-propanone, benzyl dimethyl ketal, 1-hydroxycyclohexyl phenyl ketone,
2-hydroxy-2-methyl-1-phenylpropane-
Examples thereof include 1-one, alkylphenyl glyoxylate, diethoxyacetophenone, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -1-butanone and acylphosphine oxide. The content of these photoradical polymerization initiators is preferably 0.01 to 20% by weight based on the compound having a (meth) acryloyl group.

In the present invention, the composition of the first invention is selected from the above-mentioned compound having an epoxy group, compound having a vinyl ether group and [compound having a (meth) acryloyl group and photoradical polymerization initiator]. It is also possible to mix two or more of the above. In this case, the compounding ratio thereof is 100 parts by weight with respect to the total amount of the compound having 1 to 4 oxetane rings, the compound having an epoxy group, the compound having a vinyl ether group and the compound having a (meth) acryloyl group. And the total amount of the compound having an epoxy group, the compound having a vinyl ether group and the compound having a (meth) acryloyl group is 5 to 95.
It is preferably part by weight.

The composition of the present invention contains 10 parts in addition to the above components.
Inert ingredients such as inorganic fillers, dyes, viscosity modifiers, treating agents, organic solvents and UV blockers can be incorporated in amounts of up to 100 parts by weight per 0 parts by weight of curable components. Examples of the inorganic filler include, for example, zinc oxide, aluminum oxide, antimony oxide, calcium oxide, chromium oxide, tin oxide, titanium oxide, iron oxide, copper oxide, lead oxide, bismuth oxide, magnesium oxide and manganese oxide. Metal / nonmetal oxides, aluminum hydroxide, hydroxides such as ferrous hydroxide and calcium hydroxide, salts such as calcium carbonate and calcium sulfate, silicon compounds such as silicon dioxide, kaolin, bentonite, clay and talc. Natural pigments, natural zeolites, Oya stone, minerals such as natural mica and ionite, synthetic inorganic substances such as artificial mica and synthetic zeolite, and various metals such as aluminum, iron and zinc. Some of these may overlap with the above-mentioned pigments, but these may be added to the composition as a filler, if necessary, in addition to the above-mentioned pigment as an essential component.

In addition to the photocationic polymerization initiator and / or photoradical polymerization initiator, a photosensitizer may be added to the composition of the present invention to adjust the wavelength in the UV region. Typical sensitizers that can be used in the present invention include Clevero [JV Crivello, Adv. In Polymer Sc
i., 62, 1 (1984)], and specific examples thereof include pyrene, perylene, acridine orange, thioxanthone, 2-chlorothioxanthone and benzoflavin.

Method of Use The composition of the present invention is used in various printing methods such as lithographic printing such as offset printing, letterpress printing, silk screen printing or gravure printing using paper, film or sheet as a substrate. be able to. After the printing, the composition is irradiated with active energy rays to be cured. Examples of active energy rays include ultraviolet rays, X-rays, and electron rays.
As the light source that can be used when it is cured by ultraviolet rays, various light sources can be used, and examples thereof include a pressurized or high pressure mercury lamp, a metal halide lamp, a xenon lamp, an electrodeless discharge lamp or a carbon arc lamp. In the case of curing with an electron beam, various irradiation devices can be used, and examples thereof include Cockloft-Waltsin type, Van de Graaff type, or resonance transformer type, and the electron beam having an energy of 50 to 1000 eV is preferable. , And more preferably 100 to 300 eV. In the present invention, it is preferable to use ultraviolet rays for curing the composition, because an inexpensive device can be used.

[0067]

EXAMPLES The present invention will be described more specifically with reference to Examples and Comparative Examples below. The parts in the following examples are based on weight.

Example 1 Preparation of Composition As a compound having an oxetane ring, the following compound (32) having the following two oxetane rings (hereinafter referred to as component A)
100 parts, and the following compound (3
3) 4 parts (hereinafter component G), 20 parts of pigment (Shimla First Yellow-GTF235D), 1.5 parts of talc and 2 parts of wax are mixed, and the mixture is kneaded with a three-roll mill to be an active energy ray-curable type. An ink composition was produced.

[0069]

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[0070]

[Chemical 33]

Evaluation The following evaluations were performed on the obtained composition and cured film. The results are shown in Table 2 below.

O Misting test When the incometer was operated under the condition of 1200 rpm, the state in which the ink was scattered in the form of mist around was visually evaluated and judged. ○: Does not scatter. Δ: Slightly scattered. X: Scatter.

Curable property The obtained composition was applied on a bonderite steel plate having a thickness of 0.8 mm, a width of 50 mm and a length of 150 mm to a thickness of 10 μm, and the composition was condensed at 80 W / cm at a light concentration of 80 W / cm. 10 cm below the high pressure mercury lamp of the mold, conveyer speed 10
Under a condition of m / min, it was repeatedly passed under a mercury lamp to be cured. Under the above-mentioned curing conditions, the number of passes (the number of passes) until the tackiness disappeared from the surface was evaluated.

Pencil Hardness The cured film obtained above was evaluated according to JIS K 5400.

Solvent resistance The cured film obtained above was rubbed with a cotton swab impregnated with methyl ethyl ketone, and the number of times until the base became visible was displayed.

Examples 2 to 7 Active energy ray-curable ink compositions were produced in the same manner as in Example 1 except that the components shown in Table 1 were used. About the obtained composition and cured film, Example 1
It evaluated similarly to. Table 2 shows the results.

Comparative Examples 1 to 3 Active energy ray-curable ink compositions were produced in the same manner as in Example 1 except that the components shown in Table 1 were used. About the obtained composition and cured film, Example 1
It evaluated similarly to. Table 2 shows the results.

[0078]

[Table 1]

In Table 1, each numeral indicates a part. Further, in Table 1, components B to H represent the following compounds.

Component B (compound having three oxetane rings)

[0081]

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Component C (compound having one oxetane ring)

[0083]

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Component D (compound having two epoxy groups)

[0085]

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Component E (compound having two vinyl ether groups)

[0087]

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Component F (compound having two acryloyl groups)

[0089]

[Chemical 38]

Component H (photoradical polymerization initiator)

[0091]

[Chemical Formula 39]

[0092]

[Table 2]

[0093]

Industrial Applicability The active energy ray-curable ink composition of the present invention has a high curing rate, excellent printability such as misting, and excellent surface hardness and solvent resistance as a printed matter after curing. It has high quality.

Claims (4)

[Claims] 1. A compound having 1 to 4 oxetane rings,
An active energy ray-curable ink composition comprising a photocationic polymerization initiator and a pigment. 2. The active energy ray-curable ink composition according to claim 1, further comprising a compound having an epoxy group. 3. The active energy ray-curable ink composition according to claim 1, further comprising a compound having a vinyl ether group. 4. The active energy ray-curable ink composition according to claim 1, further comprising a compound having a (meth) acryloyl group and a photoradical polymerization initiator.