JP2008169231A - Active energy ray curing type composition, active energy ray curing type ink, method for curing active energy ray curing type composition and method for forming image - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an active energy ray curing type composition having high sensitivity even in a long wavelength region, good preservation stability of the composition and excellent adhesiveness of a cured product to a substrate, to provide an active energy ray curing type ink having high image quality and good preservation stability, excellent curability and high adhesiveness to the substrate hardly susceptible to environmental effects and to provide a method for curing the composition and the ink. <P>SOLUTION: The active energy ray curing type composition, the active energy ray curing type ink and the method for curing the composition and the ink are characterized by comprising at least one compound represented by general formula (1) and at least one cationically polymerizable compound. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an actinic radiation curable composition containing a photoacid generator, an actinic radiation curable ink, and a curing method thereof.

  The actinic ray curable composition, in particular, the ultraviolet curable cationic polymerizable composition, and the cured product thereof are useful materials for various applications such as adhesives, inkjet inks, resists, display members such as color filters, and the like. Are known.

  By using a triarylsulfonium salt having a specific structure as a photoacid generator, the present applicant does not release benzene harmful to the human body and can be cured stably in various environments. (For example, refer to Patent Document 1). However, the sensitivity is still insufficient for actinic rays in the long wavelength region, and there is a problem with the substrate adhesion of the cured product.

On the other hand, a photoacid generator having a structure in which two aryl groups of a triarylsulfonium salt are linked to each other is disclosed (see, for example, Patent Document 2). When this is used for an actinic ray curable composition, curing is performed. Various physical properties such as storage stability and odor are insufficient. Moreover, although the sulfonium salt which has the special substituent in the isolated aryl group of the triarylsulfonium salt which two aryl groups connected mutually is disclosed (for example, refer patent document 3, 4), These are disclosed. The technology has not sufficiently improved the sensitivity to actinic rays in the long wavelength region and various physical properties of the cured product.
JP 2006-104185 A U.S. Pat. No. 4,161,478 International Publication Number WO2003 / 008404 Pamphlet International Publication Number WO2003 / 072567 Pamphlet

  The object of the present invention is an actinic ray curable composition having high sensitivity in a long wavelength region, good composition storage stability, excellent cured substrate adhesion, and high image quality and storage stability. The present invention provides an actinic ray curable ink having excellent curability and high substrate adhesion, and a method for curing the same.

  The above object of the present invention can be achieved by the following configuration.

  1. An actinic ray curable composition comprising at least one compound represented by the following general formula (1) and at least one cationically polymerizable compound.

(In the formula, R ₁ , R ₂ and R ₄ are substituents, and m, n and p each represents an integer of 0 to _4. X is a divalent linking group which is a single bond or the following moiety. R ₃ is any group selected from the structural formula group (A-1), R ₃ is any group selected from the following partial structural formula group (B-1), and Z ⁻ represents a counter anion. .)

(In the formula, * part represents a bonding site. R ₅ represents a hydrogen atom or a substituent. K represents an integer of 1 to 6.)

(In the formula, * part is a bonding site. R _A represents a substituent, Alk represents an unsubstituted alkyl group or an unsubstituted cycloalkyl group, Ar represents a substituted or unsubstituted aryl group, and H _Ar represents Represents a substituted or unsubstituted heteroaryl group, R ₆ represents a hydrogen atom or a substituent, a bond whose terminal is drawn inside the ring structure is bonded to any carbon atom on the ring, and t Is an integer from 0 to 11.)
2. 2. The actinic ray curable composition according to 1 above, wherein X in the general formula (1) is any one of a single bond, a sulfur atom, and a carbonyl group.

  3. 3. The actinic ray curable composition according to 2 above, wherein X in the general formula (1) is a carbonyl group.

4). R ₁ and R _{2 in} the general formula (1) are each independently a halogen atom, an alkyl group, an alkoxy group, an alkylthio group, or an alkylamino group, and R ₄ is a halogen atom, a hydroxyl group, or an alkyl group. , An alkoxy group, an alkylthio group, an alkylamino group, and in the partial structural formula group (A-1), R ₅ is a hydrogen atom, an alkyl group, an aryl group, an acyl group, or any hydrogen atom. The atoms are removed to form a linking group and bond to any carbon atom of the general formula (1) to form a ring structure, and R _{A of the} partial structural formula group (B-1) is a halogen atom, an alkyl group, an alkoxy group group, an alkylthio group, or an alkylamino group, R ₆ is a hydrogen atom or an alkyl group, an aryl group, or, or any linking group removed a hydrogen atom of the acyl group It is in any photocurable composition according to any one of the 1 to 3, wherein the configuring a ring structure with the carbon atoms of the general formula (1).

  5. 5. The actinic ray curable composition according to any one of 1 to 4, wherein the cationic polymerizable compound is an alicyclic epoxy compound represented by the following general formula (C).

(Wherein R ₂₀₁ and R ₂₀₂ each independently represents a halogen atom, an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, an acyl group, an acyloxy group, an alkoxycarbonyl group, m20, n20 represents 0, 1 or 2. r0 represents 1 to 3. L ₀ represents an r0 + 1-valent linking group or a single bond having 1 to 15 carbon atoms which may contain an oxygen atom or a sulfur atom in the main chain. )
6). 6. The actinic ray curable ink comprising the actinic ray curable composition according to any one of 1 to 5 above.

  7. A curing method for an actinic radiation curable composition, wherein the actinic radiation curable composition according to any one of 1 to 5 is cured by irradiating the actinic radiation.

  8). 7. The method for curing an actinic ray curable ink, wherein the actinic ray curable ink according to 6 is cured by irradiating the actinic ray.

  9. 7. An image forming method, wherein the actinic ray curable ink described in 6 is ejected imagewise onto a recording material from an ink jet recording head, and printing is performed on the recording material.

  According to the present invention, high sensitivity in the long wavelength region, good storage stability of the composition, actinic ray curable composition excellent in substrate adhesion of the cured product, and good image quality and storage stability Thus, it was possible to provide an actinic ray curable ink having excellent curability and high substrate adhesion that are hardly affected by the environment, and a curing method thereof.

  The present invention will be described in more detail.

In the general formula (1), R ₁ and R ₂ are substituents, and the substituents are not particularly limited, and may be alkyl groups (for example, methyl group, ethyl group, propyl group, isopropyl group, butyl group, tert-butyl). Group, isobutyl group, sec-butyl group, pentyl group, tert-pentyl group, hexyl group, 2-methylpentyl group, isohexyl group, heptyl group, isoheptyl group, 1-propylbutyl group, octyl group, 2-ethylhexyl group, Isooctyl group, nonyl group, isononyl group, decyl group, isodecyl group, undecyl group, dodecyl group, etc.), cycloalkyl group (for example, cyclopropyl group, cyclobutyl group, cyclopentyl group, cyclohexyl group, cycloheptyl group, etc.), alkenyl group ( For example, vinyl group, 1-propenyl group, 2-propenyl group, butenyl group, -Butenyl group, allyl group, etc.), cycloalkenyl group (cyclopentenyl group, cyclopentadienyl group, cyclohexenyl group, cyclooctadienyl group, etc.), alkynyl group (for example, acetylenyl group, propynyl group, butynyl group, propargyl group) Group), aryl group (for example, phenyl group, naphthyl group, anthracenyl group, phenanthrenyl group, pyrenyl group, pentacenyl group, etc.), heterocyclic group (for example, furyl group, thienyl group, pyridyl group, pyridazinyl group, pyrimidyl group, Aromatic groups such as pyrazyl group, triazyl group, imidazolyl group, pyrazolyl group, thiazolyl group, benzoimidazolyl group, benzoxazolyl group, quinazolyl group, phthalazyl group, pyrrolyl group, 2-quinolyl group, 1-isoquinyl group, etc. Pyrrolidyl group, imidazolidyl group, Ruphorino group, oxazolidyl group, 2-tetrahydrofuranyl group, 2-tetrahydrothienyl group, 2-tetrahydropyranyl group, non-aromatic group such as 3-tetrahydropyranyl group), halogen atom (fluorine atom, chlorine atom, bromine atom) An iodine atom), a cyano group, a hydroxyl group, a carboxyl group, an alkoxy group (for example, an alkoxy group formed by combining the above-described alkyl group and oxygen atom), an aryloxy group (the aryl group is the same as the above-mentioned aryl group) Synonyms), silyloxy groups, heterocyclic oxy groups (heterocycles are as defined above for heterocyclic groups), acyloxy groups, carbamoyloxy groups, alkoxycarbonyloxy groups (alkoxy moieties are as defined above for alkoxy groups) , Aryloxycarbonyloxy group (aryl part) Is synonymous with the above-mentioned aryl group), amino group, alkyl and arylamino group (the alkyl moiety and the aryl moiety are as defined above for alkyl group and aryl group, respectively), anilino group, acylamino group, aminocarbonylamino Group, alkoxycarbonylamino group (alkoxy moiety is as defined above for alkoxy group), aryloxycarbonylamino group (aryl moiety is as defined for aryl group as described above), sulfamoylamino group, alkyl and arylsulfonylamino Groups (the alkyl moiety and the aryl moiety are as defined above for the alkyl group and the aryl group, respectively), the mercapto group, the alkylthio group (the alkyl moiety is the same as the alkyl group described above), and the arylthio group (the aryl group moiety is as defined above) The aryl As defined above), a heterocyclic thio group (the heterocyclic ring is as defined above for the heterocyclic group), sulfamoyl group, sulfo group, alkyl and arylsulfinyl group, alkyl and arylsulfonyl group (alkyl moiety) The aryl moiety is as defined above for the alkyl group and aryl group), the acyl group, the aryloxycarbonyl group (the aryl moiety is as defined above for the aryl group), and the alkoxycarbonyl group (alkoxy moiety). Is synonymous with the aforementioned alkoxy group), carbamoyl group, aryl and heterocyclic azo group (aryl moiety and heterocyclic moiety are synonymous with the aforementioned aryl group and heterocyclic group), imide group, silyl group, hydrazino group, ureido group, Boronic acid group, phosphato group, sulfato group, other A well-known substituent is mentioned. These groups may be further substituted with the same substituent. m and n are integers from 0 to 4, preferably 0 to 3, and more preferably 0 to 2. When m and n are each 2 or more, the plurality of R ₁ and R ₂ may be the same or different. R ₁ and R ₂ are each formed by removing a hydrogen atom at an arbitrary position to form a bond, and R ₁ and R ₂ , or a plurality of R _{1 s} , or a plurality of R _{2 s} bonded together to form a ring. May be.

R ₁ and R ₂ are preferably a halogen atom, an alkyl group, an alkoxy group, an alkylthio group, or an alkylamino group, and more preferably a halogen atom, an alkyl group, or an alkoxy group.

R ₄ is a substituent and includes a substituent having the same meaning as R ₁ , but these are not further substituted. p is an integer from 0 to 4, preferably 0 to 3, and more preferably 0 to 2. When p is 2 or more, the plurality of R ₄ may be the same or different.

R ₄ is preferably a halogen atom, a hydroxyl group, an alkyl group, an alkoxy group, an alkylthio group, or an alkylamino group.

X is a divalent linking group, and is a single bond or any group selected from the partial structural formula group (A-1). Examples of the substituent represented by R ₅ include the same substituents as R ₁ , R ₂ and R _4, and an alkyl group, an aryl group or an acyl group is preferred. R ₅ may remove any hydrogen atom to form a linking group and bond to any carbon atom of the general formula (1) to form a ring structure. X is preferably a single bond, a sulfur atom or a carbonyl group, more preferably a carbonyl group.

R ₃ is any group selected from the above partial structural formula group (B-1).

There is no restriction | limiting in particular as a substituent which _RA represents, For example, the substituent synonymous with R < ₁ >, R < ₂ > is mentioned, Furthermore, you may substitute by the synonymous substituent. The alkyl group or cycloalkyl group represented by Alk has the same meaning as the above-described alkyl group or cycloalkyl group, respectively, but this is not further substituted. The aryl group represented by Ar is as defined above, and the heteroaryl group represented as H _Ar is as defined above. Ar and H _Ar may be substituted, and examples of the substituent include a substituent having the same meaning as R _A.

R ₆ has the same meaning as R ₅ . When t is 2 or more, the plurality of R _A may be the same or different.

More preferred as R ₃ are those listed in the following partial structural formula group (B-2).

(In the formula, * part is a bonding site. R _A represents a substituent, Alk represents an unsubstituted alkyl group or an unsubstituted cycloalkyl group, Ar represents a substituted or unsubstituted aryl group, and H _Ar represents Represents a substituted or unsubstituted heteroaryl group, and R ₆ represents a hydrogen atom or a substituent.)
In the actinic ray curable composition of the present invention, even if any of the compounds represented by the general formula (1) is used, the substrate adhesion of the cured product is improved, but from the viewpoint of the flexibility of the cured product. R ₃ in the general formula (1) is a part of the partial structural formula group (B-1)

From the viewpoint of the scratch strength of the cured product, R ₃ is preferably

From the viewpoint of storage stability of the cured product, R ₃ is preferably

From the viewpoint of curing stability against changes in humidity of the composition, R ₃ is preferably

From the viewpoint of curling suppression of the cured product, R ₃ is preferably

It is preferable that it is either.

R ₃ and R ₄ may be bonded to each other by removing a hydrogen atom from an arbitrary position and may be bonded to each other to form a ring.

Z ⁻ represents a counter anion. Counter anions include complex ions such as BF ₄ ⁻ , B (C ₆ F ₅ ) ₄ ⁻ , PF ₆ ⁻ , AsF ₆ ⁻ and SbF ₆ ⁻ , p-CH ₃ C ₆ H ₄ SO ₃ ⁻ and CF _3. Examples thereof include sulfonate ions such as SO ₃ ^−, from the viewpoint of acid generation ability, borate ions and PF ₆ ⁻ are preferable, and PF ₆ ⁻ is more preferable.

  Specific examples of the compound represented by the general formula (1) are shown below, but the present invention is not limited thereto.

  A method for synthesizing the compound represented by the general formula (1) will be described. The compound represented by the general formula (1) may be synthesized by any method. For example, an existing cyclic sulfide compound is oxidized with various oxidizing agents to form a cyclic sulfoxide compound, which reacts with an oxygen atom of the sulfoxide. Together with a compound that forms a leaving group from a sulfur atom, in the presence of a suitable acid catalyst, a nucleophilic reagent such as an alkylating agent, an arylating agent (relative to the leaving group on S). A desired sulfonium structure can be formed by adding a nucleophilic compound) to the compound by salt exchange using a conventionally known method to synthesize a compound represented by the general formula (1). I can do it.

  The method for synthesizing the compound represented by the general formula (1) will be described below with specific examples, but the present invention is not limited to this.

(Synthesis of 1-11: General synthesis method of the compound represented by the general formula (1))
To 24 g of isopropylthioxanthone, 1200 ml of acetonitrile and 400 ml of water were added and dissolved, and then 207 g of ceric ammonium nitrate was further added and stirred for 4 hours. Water was added, the organic matter was extracted with ethyl acetate, washed with water, and dried over magnesium sulfate. After concentration by filtration, the residue was purified by silica gel chromatography to obtain 15 g of a sulfoxide form of isopropylthioxanthone.

15 g of sulfoxide, 13.4 g of diphenyl sulfide, 48 ml of acetic acid, 48 ml of acetic anhydride and 12 ml of methylene chloride were added, and 18 ml of concentrated sulfuric acid was added dropwise with stirring in an ice-water bath. After 2 hours, water was added to stop the reaction, extraction was performed with methylene chloride, and concentration was performed, followed by purification by silica gel chromatography. This was dissolved in acetic acid and added dropwise to the stirring KPF ₆ aqueous solution, and the resulting solid was collected by filtration and dried to obtain 3 g of 1-11.

  In the actinic ray curable composition of the present invention, the content of the compound represented by the general formula (1) is not limited, but is 0.2 to 20 parts by mass with respect to 100 parts by mass of the cationic polymerizable compound described later. It is preferable to make it contain in the ratio. Moreover, the compound represented by General formula (1) can select and use 1 type (s) or 2 or more types.

[Cationically polymerizable compound]
Next, the cationic polymerizable compound will be described.

  The cationically polymerizable compound according to the present invention is a type in which polymerization is caused by cationic polymerization, (1) a compound having an oxirane ring (also referred to as an epoxy compound), (2) a styrene derivative, (3) a vinylnaphthalene derivative, (4) Vinyl ethers, (5) N-vinyl compounds, and (6) compounds having an oxetane ring, and the like. Among them, particularly in the present invention, a compound having an oxirane ring (also referred to as an epoxy compound). It is preferable to use a compound having an oxetane ring.

(1) A compound having an oxirane ring (also referred to as an epoxy compound)
Although there is no restriction | limiting in particular as a compound which has an oxirane ring, The compound which has an oxirane ring in 1 molecule can be mentioned. Examples of such epoxy compounds include alicyclic epoxies (also referred to as alicyclic epoxies and alicyclic epoxy compounds), glycidyl esters of polybasic acids, glycidyl ethers of polyhydric alcohols, and polyoxyalkylene glycols. Glycidyl ethers, aromatic polyol glycidyl ethers, aromatic polyol glycidyl ether hydrogenated compounds, urethane polyepoxy compounds and epoxidized polybutadienes. These compounds can be used alone or in a mixture of two or more. An epoxy compound that can be suitably used in the present invention is an alicyclic epoxy compound.

  In the actinic ray curable composition of the present invention, by using a polyfunctional alicyclic epoxy compound in combination, a further sensitivity enhancement effect or a cured film physical property improvement effect can be obtained.

  Among the polyfunctional alicyclic epoxies, the polyfunctional epoxy compound represented by the general formula (C) is preferable.

Examples of the substituent represented by R ₂₀₁ and R ₂₀₂ include a halogen atom (eg, chlorine atom, bromine atom, fluorine atom), an alkyl group having 1 to 6 carbon atoms (eg, methyl group, ethyl group, propyl group, Isopropyl group, butyl group), alkoxy group having 1 to 6 carbon atoms (for example, methoxy group, ethoxy group, n-propoxy group, iso-propoxy group, n-butoxy group, t-butoxy group), acyl group (for example, Acetyl group, propionyl group, trifluoroacetyl group), acyloxy group (for example, acetoxy group, propionyloxy group, trifluoroacetoxy group), alkoxycarbonyl group (for example, methoxycarbonyl group, ethoxycarbonyl group, t-butoxycarbonyl group) ). As the substituent, an alkyl group, an alkoxy group, and an alkoxycarbonyl group are preferable.

In L ₀ , examples of the divalent linking group having 1 to 15 carbon atoms that may contain an oxygen atom or a sulfur atom in the main chain include the following groups and these groups and —O— group, —S— group, Examples include groups formed by combining a plurality of —CO— groups and —CS— groups.

Methylene group [—CH ₂ —]
Ethylidene group [> CHCH ₃ ]
Isopropylidene [> C (CH ₃ ) ₂ ]
1,2-ethylene group [—CH ₂ CH ₂ —]
1,2-propylene group [—CH (CH ₃ ) CH ₂ —]
1,3-propanediyl group [—CH ₂ CH ₂ CH ₂ —]
2,2-dimethyl-1,3-propanediyl group [—CH ₂ C (CH ₃ ) ₂ CH ₂ —]
2,2-dimethoxy-1,3-propanediyl group [—CH ₂ C (OCH ₃ ) ₂ CH ₂ —]
2,2-dimethoxymethyl-1,3-propanediyl group [—CH ₂ C (CH ₂ OCH ₃ ) ₂ CH ₂ —]
1-methyl-1,3-propanediyl group [—CH (CH ₃ ) CH ₂ CH ₂ —]
1,4-butanediyl group [—CH ₂ CH ₂ CH ₂ CH ₂ —]
1,5-pentanediyl group [—CH ₂ CH ₂ CH ₂ CH ₂ CH ₂ —]
Oxydiethylene group [—CH ₂ CH ₂ OCH ₂ CH ₂ —]
Thiodiethylene group [—CH ₂ CH ₂ SCH ₂ CH ₂ —]
3-oxothiodiethylene group [—CH ₂ CH ₂ SOCH ₂ CH ₂ —]
3,3-dioxothiodiethylene group [—CH ₂ CH ₂ SO ₂ CH ₂ CH ₂ —]
1,4-dimethyl-3-oxa-1,5-pentanediyl group [—CH (CH ₃ ) CH ₂ OCH (CH ₃ ) CH ₂ —]
3-oxopentanediyl group [—CH ₂ CH ₂ COCH ₂ CH ₂ —]
1,5-dioxo-3-oxapentanediyl group [—COCH ₂ OCH ₂ CO—]
4-Oxa-1,7-heptanediyl group [—CH ₂ CH ₂ CH ₂ OCH ₂ CH ₂ CH ₂ —]
3,6-dioxa-1,8-octanediyl group [—CH ₂ CH ₂ OCH ₂ CH ₂ OCH ₂ CH ₂ —]
1,4,7-trimethyl-3,6-dioxa-1,8-octanediyl group [—CH (CH ₃ ) CH ₂ OCH (CH ₃ ) CH ₂ OCH (CH ₃ ) CH ₂ —]
5,5-dimethyl-3,7-dioxa-1,9-nonanediyl group [—CH ₂ CH ₂ OCH ₂ C (CH ₃ ) ₂ CH ₂ OCH ₂ CH ₂ —]
5,5-dimethoxy-3,7-dioxa-1,9-nonanediyl group [—CH ₂ CH ₂ OCH ₂ C (OCH ₃ ) ₂ CH ₂ OCH ₂ CH ₂ —]
5,5-dimethoxymethyl-3,7-dioxa-1,9-nonanediyl group [—CH ₂ CH ₂ OCH ₂ C (CH ₂ OCH ₃ ) ₂ CH ₂ OCH ₂ CH ₂ —]
4,7-dioxo-3,8-dioxa-1,10-decandiyl group [—CH ₂ CH ₂ O—COCH ₂ CH ₂ CO—OCH ₂ CH ₂ —]
3,8-dioxo-4,7-dioxa-1,10-decandiyl group [—CH ₂ CH ₂ CO—OCH ₂ CH ₂ O—COCH ₂ CH ₂ —]
1,3-cyclopentanediyl group [-1,3-C ₅ H ₈ —]
1,2-cyclohexanediyl group [-1,2-C ₆ H _10- ]
1,3-cyclohexanediyl group [-1,3-C ₆ H _10- ]
1,4-cyclohexanediyl group [-1,4-C ₆ H _10- ]
2,5-tetrahydrofurandiyl group [2,5-C ₄ H ₆ O—]
p- phenylene _{[-p-C 6 H 4 -} ]
m- phenylene group _{[-m-C 6 H 4 -} ]
α, α′-o-xylylene group [—o—CH ₂ —C ₆ H ₄ —CH ₂ —]
α, α'-m- xylylene group _{[-m-CH 2 -C 6 H} 4 -CH 2 -]
α, α'-p- xylylene group _{[-p-CH 2 -C 6 H} 4 -CH 2 -]
Furan-2,5-diyl - bismethylene group _{[2,5-CH 2 -C 4 H} 2 O-CH 2 -]
Thiophene-2,5-diyl-bismethylene group [2,5-CH ₂ —C ₄ H ₂ S—CH ₂ —]
Isopropylidenebis -p- phenylene group _{[-p-C 6 H 4 -C} (CH 3) 2 -p-C 6 H 4 -].

  Examples of the trivalent or higher linking group include a group formed by removing a hydrogen atom at an arbitrary site from the divalent linking group described above as much as necessary, and an —O— group, —S— group, —CO—. And a group formed by combining a plurality of groups and -CS- groups.

L ₀ may have a substituent. Examples of the substituent include a halogen atom (for example, chlorine atom, bromine atom, fluorine atom), an alkyl group having 1 to 6 carbon atoms (for example, methyl group, ethyl group, propyl group, isopropyl group, butyl group), An alkoxy group having 1 to 6 carbon atoms (for example, methoxy group, ethoxy group, n-propoxy group, iso-propoxy group, n-butoxy group, t-butoxy group), acyl group (for example, acetyl group, propionyl group, Trifluoroacetyl group), acyloxy group (for example, acetoxy group, propionyloxy group, trifluoroacetoxy group), alkoxycarbonyl group (for example, methoxycarbonyl group, ethoxycarbonyl group, t-butoxycarbonyl group) and the like. As the substituent, an alkyl group, an alkoxy group, and an alkoxycarbonyl group are preferable.

L ₀ is preferably a divalent linking group having 1 to 8 carbon atoms which may contain an oxygen atom or a sulfur atom in the main chain, and more preferably a divalent linking group having 1 to 5 carbon atoms in which the main chain is composed solely of carbon. preferable.

  Particularly preferred alicyclic epoxies are those represented by the following general formula (C-I) or (C-II) in terms of producing a cured film with high hardness and further improving the adhesion of the cured film to the substrate. A compound.

In the formula, R ₂₁₁ and R ₂₁₂ represent substituents, and m21 and n21 represent 0, 1 or 2. p1 and q1 each represents 0 or 1. r1 represents 1-3. L ₁ represents a C 1-15 r 1 + 1 valent linking group or single bond that may contain an oxygen atom or a sulfur atom in the main chain.

In the formula, R ₂₃₁ and R ₂₃₂ each represent a substituent, and m22 and n22 each represent 0, 1 or 2. p2 and q2 each represents 0 or 1. r2 represents 1-3. L ₂ represents an r2 + 1-valent linking group or a single bond having 1 to 15 carbon atoms which may contain an oxygen atom or a sulfur atom in the main chain.

In the above formula, as R ₂₁₁ , R ₂₁₂ , R ₂₂₁ , and R ₂₂₂ , a halogen atom (eg, chlorine atom, bromine atom, fluorine atom), an alkyl group having 1 to 20 carbon atoms (eg, methyl group, ethyl group) Group, propyl group, isopropyl group, butyl group), alkoxy group having 1 to 20 carbon atoms (for example, methoxy group, ethoxy group, n-propoxy group, iso-propoxy group, n-butoxy group, tert-butoxy group) An acyl group (for example, acetyl group, propionyl group, trifluoroacetyl group), an acyloxy group having 1 to 20 carbon atoms (for example, an acetoxy group, propionyloxy group, trifluoroacetoxy group), 1 to 20 carbon atoms An alkoxycarbonyl group (for example, a methoxycarbonyl group, an ethoxycarbonyl group, a t-butoxycarbonyl group), an alkyl group having 2 to 20 carbon atoms Examples include a thiothiocarbonyl group (for example, methylthiocarbonyl group, ethylthiocarbonyl group, t-butylthiocarbonyl group), aryloxycarbonyl group, alkylsulfonyl group, arylsulfonyl group, cyano group, nitro group and the like. As the substituent, an alkyl group, an alkoxy group, and an alkoxycarbonyl group are preferable.

Examples of the divalent linking group having 1 to 15 carbon atoms that may contain an oxygen atom or a sulfur atom in the main chain represented by L ₁ and L ₂ are the same as those described in the description of L ₀ . L ₁ and L ₂ are preferably a C 1-8 divalent linking group that may contain an oxygen atom or a sulfur atom in the main chain, and the C 1-5 divalent linking group in which the main chain consists only of carbon. Groups are more preferred.

  A particularly preferred alicyclic epoxy is a compound represented by the following general formula (C-III) or (C-IV) in that the curing sensitivity is high and the curing sensitivity is not easily affected by changes in the printing environment. is there.

In the formula, R ₂₃₁ and R ₂₃₂ represent a substituent, and m23 and n23 represent 0 or 1. p3 and q3 each represents 0 or 1. r3 represents 1-3. L ₃ represents a C 1-15 r 3 + 1 valent linking group or single bond that may contain an oxygen atom or a sulfur atom in the main chain.

In the formula, R ₂₄₁ and R ₂₄₂ represent substituents, and m24 and n24 represent 0 or 1. p4 and q4 each represents 0 or 1. r4 represents 1-3. L ₄ represents an r4 + 1-valent linking group or a single bond having 1 to 15 carbon atoms, which may contain an oxygen atom or a sulfur atom in the main chain.

In the above formula, R ₂₃₁ , R ₂₃₂ , R ₂₄₁ and R ₂₄₂ have the same _{meanings as} R ₂₁₁ , R ₂₁₂ , R ₂₂₁ and R _{222 in the} general formula (CI) or (C-II). Examples of the divalent linking group having 1 to 15 carbon atoms that may contain an oxygen atom or a sulfur atom in the main chain represented by L ₃ and L ₄ are the same as those described in the description of L ₀ .

  Specific examples of preferable alicyclic epoxies include EP-1 to EP-146 described in paragraph numbers 0172 to 0191 of JP-A No. 2005-307162.

  The addition amount of the epoxy compound is preferably 10 to 40% by mass. If it is less than 10% by mass, the curability is remarkably changed depending on the curing environment (temperature, humidity) and cannot be used. If it exceeds 50% by mass, the film properties after curing are weak and cannot be used. A more preferable addition amount is preferably 20 to 40% by mass. In the present invention, one type of polyfunctional epoxy compound may be used alone, or two or more types may be used in appropriate combination.

  These alicyclic epoxy compounds may be produced by any method, for example, see Maruzen KK Publishing, 4th edition Experimental Chemistry Course 20 Organic Synthesis II, 213, 1992, Ed. By Alfred Hasfner, The Chemistry of Heterocyclic Compounds-Small Ring Heterocycles part3, Oxilanes, John & Wiley and Sons, An Interc. 42, 1986, Yoshimura, Adhesion, Vol. 30, No. 7, 42, 1986, JP-A Nos. 11-100308, 4-36263, and 4-69360.

  In the actinic ray curable composition of the present invention, a further sensitivity improvement effect or a cured film physical property improvement effect can be obtained by using a monofunctional epoxy together. Although there will be no restriction | limiting in particular if it is a monofunctional epoxy, In this invention, a monofunctional alicyclic epoxy is preferable and the monofunctional alicyclic epoxy represented by the following general formula (D) is more preferable.

In the formula, R ₁₀₁ represents a substituent not containing a cationic polymerizable or radical polymerizable reactive functional group, and m10 represents 1, 2, 3 or 4.

R _{101 in the} general formula (D) represents a substituent that does not contain a cationic polymerizable or radical polymerizable reactive functional group. Examples of the substituent include a halogen atom (for example, a chlorine atom, a bromine atom, a fluorine atom). Atom), an alkyl group having 1 to 20 carbon atoms (for example, methyl group, ethyl group, propyl group, isopropyl group, butyl group), cycloalkyl group having 3 to 6 carbon atoms (for example, cyclopropyl group, cyclobutyl group) , Cyclopentyl group, cyclohexyl group), alkoxy group having 1 to 20 carbon atoms (for example, methoxy group, ethoxy group, n-propoxy group, iso-propoxy group, n-butoxy group, t-butoxy group), carbon number 2 ~ 20 acyl group (for example, acetyl group, propionyl group, trifluoroacetyl group), C2-C20 acyloxy group (for example, acetoxy group) , Propionyloxy group, trifluoroacetoxy group, etc.), C2-C20 acylthio group (for example, acetylthio group, propionylthio group, trifluoroacetylthio group), C2-C20 alkoxycarbonyl group (for example, methoxy) Carbonyl group, ethoxycarbonyl group, t-butoxycarbonyl group), C2-C20 alkylthiocarbonyl group (for example, methylthiocarbonyl group, ethylthiocarbonyl group, t-butylthiocarbonyl group) and the like.

  These groups may further have a substituent. Examples of the substituent include a halogen atom (eg, chlorine atom, bromine atom, fluorine atom), an alkoxy group having 1 to 20 carbon atoms (eg, methoxy group, ethoxy group, n-propoxy group, iso-propoxy group, n- Butoxy group, t-butoxy group), acyl group having 2 to 20 carbon atoms (for example, acetyl group, propionyl group, trifluoroacetyl group), acyloxy group having 2 to 20 carbon atoms (for example, acetoxy group, propionyloxy group, Trifluoroacetoxy group etc.), C2-C20 alkoxycarbonyl group (e.g. methoxycarbonyl group, ethoxycarbonyl group, t-butoxycarbonyl group), C2-C20 alkylthiocarbonyl group (e.g. methylthiocarbonyl group, Ethylthiocarbonyl group, t-butylthiocarbonyl group), aryloxy Carbonyl group, an alkylsulfonyl group, an arylsulfonyl group, a cyano group, and nitro group go up. As the substituent, a halogen atom, an alkoxy group, an acyloxy group, and an alkoxycarbonyl group are preferable.

  A more preferred alicyclic epoxy is a compound represented by the following general formula (D-I) from the viewpoint of producing a cured film with high hardness and further improving the adhesion of the cured film to the substrate.

In the formula, R ₁₁₁ represents a substituent, and m11 represents 0, 1, 2, or 3. R ₁₁₂ , R ₁₁₃ and R ₁₁₄ each independently represent a hydrogen atom or a substituted or unsubstituted alkyl group. Y ₁₁ and Y ₁₂ each independently represent O or S, p11 represents 0, 1 or 2, q11 represents 0 or 1, r11 represents 0 or 1, and s11 represents 0 or 1.

In the above formula, examples of the substituent represented by R ₁₁₁ include a halogen atom (for example, chlorine atom, bromine atom, fluorine atom), an alkyl group having 1 to 20 carbon atoms (for example, methyl group, ethyl group, propyl group). Group, isopropyl group, butyl group), alkoxy group having 1 to 20 carbon atoms (for example, methoxy group, ethoxy group, n-propoxy group, iso-propoxy group, n-butoxy group, t-butoxy group), acyl group (For example, acetyl group, propionyl group, trifluoroacetyl group), acyloxy group having 1 to 20 carbon atoms (for example, acetoxy group, propionyloxy group, trifluoroacetoxy group), alkoxycarbonyl group having 1 to 20 carbon atoms (For example, methoxycarbonyl group, ethoxycarbonyl group, t-butoxycarbonyl group), alkylthiocarbon having 2 to 20 carbon atoms Bonyl groups (for example, methylthiocarbonyl group, ethylthiocarbonyl group, t-butylthiocarbonyl group), aryloxycarbonyl group, alkylsulfonyl group, arylsulfonyl group, cyano group, nitro group and the like can be mentioned. As the substituent, an alkyl group, an alkoxy group, and an alkoxycarbonyl group are preferable.

R ₁₁₂ , R ₁₁₃ and R ₁₁₄ represent a hydrogen atom or a substituted or unsubstituted alkyl group. As an example of an alkyl group, the same group as the example of the alkyl group of _R111 mentioned above can be mentioned. Examples of the substituent of the alkyl group having a substituent include a halogen atom (eg, chlorine atom, bromine atom, fluorine atom), an alkoxy group having 1 to 20 carbon atoms (eg, methoxy group, ethoxy group, n-propoxy). Group, iso-propoxy group, n-butoxy group, t-butoxy group), acyl group (for example, acetyl group, propionyl group, trifluoroacetyl group), acyloxy group having 1 to 20 carbon atoms (for example, acetoxy group, Propionyloxy group, trifluoroacetoxy group), C1-C20 alkoxycarbonyl group (for example, methoxycarbonyl group, ethoxycarbonyl group, t-butoxycarbonyl group), C2-C20 alkylthiocarbonyl group (for example, Methylthiocarbonyl group, ethylthiocarbonyl group, t-butylthiocarbonyl group) An aryloxycarbonyl group, an alkylsulfonyl group, an arylsulfonyl group, a cyano group, a nitro group and the like, Preferable substituents are an alkoxy group, an alkoxycarbonyl group.

Y ₁₁ and Y ₁₂ represent O or S, and O is preferable. m11 represents 0 to 3 and is preferably 1 or 2. p11 represents 0, 1 or 2, and q11, r11 and s11 represent 0 or 1.

  A particularly preferred alicyclic epoxy is a compound represented by the following general formula (D-II) from the viewpoint of producing a cured film having high hardness and further improving the adhesion of the cured film to the substrate.

In the formula, R ₁₂₁ represents a substituent, and m12 represents 0, 1 or 2. R ₁₂₂ , R ₁₂₃ and R ₁₂₄ each independently represent a hydrogen atom or a substituted or unsubstituted alkyl group. Y ₂₁ and Y ₂₂ each independently represent O or S, p12 represents 0, 1 or 2, q12 represents 0 or 1, r12 represents 0 or 1, and s12 represents 0 or 1.

In the above formula, R ₁₂₁ has the same meaning as R ₁₁₁ . Y ₂₁ and Y ₂₂ represent O or S, and O is preferred. m12 represents 0 to 2, and 0 or 1 is preferable. p12 represents 0, 1 or 2, and q12, r12 and s12 represent 0 or 1. R ₁₂₂ , R ₁₂₃ , and R ₁₂₄ are synonymous with R ₁₁₂ , R ₁₁₃ , and R ₁₁₄ .

  The alicyclic epoxy that is more preferable in terms of high curing sensitivity, improved substrate adhesion of the cured film, and is less susceptible to curing sensitivity due to changes in the printing environment, is represented by the following general formula (D-III): It is a compound represented by general formula (D-IV) or general formula (D-V).

In the formula, R ₁₃₁ represents a substituent, and m13 represents 0, 1 or 2. R ₁₃₂ , R ₁₃₃ and R ₁₃₄ each independently represents a hydrogen atom or a substituted or unsubstituted alkyl group. p13 represents 0, 1 or 2, and q13 represents 0 or 1.

In the formula, R ₁₄₁ represents a substituent, and m14 represents 0, 1 or 2. R ₁₄₂ , R ₁₄₃ and R ₁₄₄ each independently represent a hydrogen atom or a substituted or unsubstituted alkyl group. p14 represents 0, 1 or 2.

In the formula, R ₁₅₁ represents a substituent, and m15 represents 0, 1 or 2. R ₁₅₄ represents a hydrogen atom or a substituted or unsubstituted alkyl group. s15 represents 0 or 1.

In the above formula, R ₁₃₁ , R ₁₄₁ and R ₁₅₁ are as defined above for R ₁₁₁ . m13, m14 and m15 represent 0 to 2, and 0 or 1 is preferable. p13 and p14 represent 0, 1 or 2, and q13 and s15 represent 0 or 1. R ₁₃₂ , R ₁₃₃ , R ₁₃₄ , R ₁₄₂ , R ₁₄₃ , R ₁₄₄ , and R ₁₅₄ are synonymous with R ₁₁₂ , R ₁₁₃ , and R ₁₁₄ .

  A particularly preferred alicyclic epoxy is represented by the following general formula (D-VI) in that it has high curing sensitivity, improves the adhesion of the cured film to the substrate, and is less susceptible to curing sensitivity due to changes in the printing environment. It is a compound.

In the formula, R ₁₆₁₁ and R ₁₆₁₂ each independently represent a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. R ₁₆₂ , R ₁₆₃ and R ₁₆₄ each independently represent a hydrogen atom or a substituted or unsubstituted alkyl group. q16 represents 0 or 1.

In the above formula, R ₁₆₁₁ and R ₁₆₁₂ are a hydrogen atom or an alkyl group having 1 to 6 carbon atoms (for example, methyl group, ethyl group, propyl group, isopropyl group, butyl group, sec-butyl group, t-butyl group). , A pentyl group, a hexyl group), and an alkyl group is preferably a methyl group, an ethyl group or a propyl group. R ₁₆₂ , R ₁₆₃ and R ₁₆₄ have the same _meanings as R ₁₁₂ , R ₁₁₃ and R ₁₁₄ . q16 represents 0 or 1.

  Specific examples of the monofunctional epoxy compound according to the present invention include SEP-1 to EP-170 described in paragraph numbers 0087 to 0099 of JP-A-2005-307162.

  The addition amount of the monofunctional epoxy compound according to the present invention is preferably 10 to 20% by mass. When the amount is less than 10% by mass, imparting flexibility to the cured film becomes insufficient, and when it exceeds 20% by mass, the film physical properties after curing are weak and cannot be used. In the present invention, one type of monofunctional epoxy compound according to the present invention may be used alone, or two or more types may be used in appropriate combination.

  These alicyclic epoxy compounds may be produced by any method, for example, see Maruzen KK Publishing, 4th Edition Experimental Chemistry Course 20 Organic Synthesis II, 213, 1992, Ed. by Alfred Hasfner, The Chemistry of Heterocyclic compounds, Vol. 30, Advertisement, Small Ring Heterocycles part3, Oxilanes, John & Wiley and Sons, An Inc. No. 5, 42, 1986, Yoshimura, Adhesion, Vol. 30, No. 7, 42, 1986, JP-A-11-100308, JP-A-4-36263, JP-A-4-69360, etc. Can be synthesized.

(2) Styrene derivatives For example, styrene, p-methylstyrene, p-methoxystyrene, β-methylstyrene, p-methyl-β-methylstyrene, α-methylstyrene, p-methoxy-β-methylstyrene and the like.

(3) Vinylnaphthalene derivatives For example, 1-vinylnaphthalene, α-methyl-1-vinylnaphthalene, β-methyl-1-vinylnaphthalene, 4-methyl-1-vinylnaphthalene, 4-methoxy-1-vinylnaphthalene and the like.

(4) Vinyl ethers For example, isobutyl ether, ethyl vinyl ether, phenyl vinyl ether, p-methylphenyl vinyl ether, p-methoxyphenyl vinyl ether, α-methylphenyl vinyl ether, β-methylisobutyl vinyl ether, β-chloroisobutyl vinyl ether, and the like.

(5) N-vinyl compounds For example, N-vinylcarbazole, N-vinylpyrrolidone, N-vinylindole, N-vinylpyrrole, N-vinylphenothiazine, N-vinylacetanilide, N-vinylethylacetamide, N-vinylsuccinimide N-vinylphthalimide, N-vinylcaprolactam, N-vinylimidazole and the like.

(6) Compound having an oxetane ring As the compound having an oxetane ring, any known oxetane compound as introduced in JP-A Nos. 2001-220526 and 2001-310937 can be used. Further, the combined use of a monofunctional oxetane compound containing one oxetane ring and a polyfunctional oxetane compound containing two or more oxetane rings improves the film strength after curing and the adhesion to the recording material. preferable. However, when a compound having 5 or more oxetane rings is used, the viscosity of the ink composition becomes high, which makes it difficult to handle and the glass transition temperature of the ink composition becomes high. Will not be enough. The compound having an oxetane ring used in the present invention is preferably a compound having 1 to 4 oxetane rings.

  In the actinic ray curable composition of the present invention, it is preferable to use an oxetane compound in which the 2-position of the oxetane ring is not substituted together with the compound represented by the general formula (SX).

  Hereinafter, the oxetane compound in which the 2-position is not substituted will be described. As an example of the oxetane compound in which the 2-position is not substituted, a compound represented by the following general formula (101) can be given.

In General Formula (101), 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, an allyl group, or an aryl group. , Furyl group or thienyl group. R ² is an alkyl group having 1 to 6 carbon atoms such as methyl group, ethyl group, propyl group, butyl group, 1-propenyl group, 2-propenyl group, 2-methyl-1-propenyl group, 2-methyl-2. -Alkenyl groups having 2 to 6 carbon atoms such as propenyl group, 1-butenyl group, 2-butenyl group and 3-butenyl group, aromatic groups such as phenyl group, benzyl group, fluorobenzyl group, methoxybenzyl group and phenoxyethyl group A group having a ring, an alkylcarbonyl group having 2 to 6 carbon atoms such as an ethylcarbonyl group, a propylcarbonyl group and a butylcarbonyl group, an alkoxy having 2 to 6 carbon atoms such as an ethoxycarbonyl group, a propoxycarbonyl group and a butoxycarbonyl group Carbonyl group, ethylcarbamoyl group, propylcarbamoyl group, butylcarbamoyl group, pentylcarbamoyl group Number 2-6 carbons of an N- alkylcarbamoyl group.

  As the oxetane compound used in the present invention, it is particularly preferable to use a compound having two oxetane rings because the resulting composition has excellent tackiness, low viscosity and excellent workability.

  An example of a compound having two oxetane rings includes a compound represented by the following general formula (102).

In the general formula (102), R ¹ is the same group as that in the general formula (101). R ³ is, for example, a linear or branched alkylene group such as an ethylene group, a propylene group or a butylene group, a linear or branched poly (alkyleneoxy) such as a poly (ethyleneoxy) group or a poly (propyleneoxy) group. ) Group, propenylene group, methylpropenylene group, butenylene group or other linear or branched unsaturated hydrocarbon group, alkylene group containing carbonyl group or carbonyl group, alkylene group containing carboxyl group, alkylene containing carbamoyl group Group.

R ³ may also be a polyvalent group selected from the groups represented by the following general formulas (103), (104) and (105).

In the general formula (103), 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 carbon such as a methoxy group, an ethoxy group, a propoxy group, or a butoxy group. A C 1-4 alkoxy group, a halogen atom such as a chlorine atom or a bromine atom, a nitro group, a cyano group, a mercapto group, a lower alkyl carboxyl group, a carboxyl group, or a carbamoyl group.

In the general formula (104), R ⁵ represents an oxygen atom, a sulfur atom, a methylene group, NH, SO, SO ₂ , C (CF ₃ ) ₂ , or C (CH ₃ ) ₂ .

In General Formula (105), 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 an integer of 0-2000. R ⁷ is a methyl group, an ethyl group, a propyl group, a butyl group having 1 to 4 carbon atoms, or an aryl group. Examples of R ^{7 also} include a group selected from the group represented by the following general formula (106).

In General Formula (106), R ⁸ 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. m is an integer of 0-100.

In the compound having two oxetane rings, a preferred example other than the above compound is a compound represented by the following general formula (107). In formula (107), R ¹ has the same meaning as R ¹ in the general formula (101).

  Moreover, as an example of a compound having 3 to 4 oxetane rings, a compound represented by the following general formula (108) can be given.

In formula (108), R ¹ has the same meaning as R ¹ in the general formula (101). As R ⁹ , for example, a branched alkylene group having 1 to 12 carbon atoms such as groups represented by the following A to C, a branched poly (alkyleneoxy) group such as a group represented by the following D, or the following E And branched polysiloxy groups such as those shown. j is 3 or 4.

In the above A, R ¹⁰ is a lower alkyl group such as a methyl group, an ethyl group or a propyl group. In D, p is an integer of 1 to 10.

  Further, examples of the compound having 1 to 4 oxetane rings other than those described above include compounds represented by the following general formula (109).

In formula (109), R ⁸ has the same meaning as R ⁸ in the general formula (106). 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.

  Preferable specific examples of oxetane compounds that can be used in the present invention include, for example, Exemplified Compounds 11 and 12 described in Paragraph No. 0121 of JP-A No. 2005-307162, Exemplified Compound 13 described in Paragraph No. 0131 , Exemplified compounds 14 to 19 described in paragraph numbers 0136 and 0137, and the like can be mentioned.

  The production method of each compound having an oxetane ring described above is not particularly limited, and may be a conventionally known method. For example, Pattison (DB Pattison, J. Am. Chem. Soc., 3455, 79 ( 1957)) discloses a method for synthesizing an oxetane ring from a diol. In addition to these, compounds having 1 to 4 oxetane rings having a high molecular weight of about 1000 to 5000 are also included. Specific examples of these compounds include the compounds described in paragraph No. 0139 of JP-A No. 2005-307162.

[Other photoacid generators]
In the actinic ray curable composition of the present invention, in addition to the compound represented by the general formula (1), a compound that generates an acid upon irradiation with an actinic ray (also simply referred to as a photoacid generator) is used. I can do it.

  As a compound that generates an acid upon irradiation with actinic rays, for example, a chemically amplified photoresist or a compound used for photocationic polymerization is used (Organic Materials Research Group, “Organic Materials for Imaging”, Bunshin Publishing) (1993), pages 187-192). Examples of compounds suitable for the present invention are listed below.

  Specific examples of the sulfonium salt that can be used in the present invention are shown below, but the present invention is not limited thereto.

[Pigments / Other additives]
In addition to the constituent elements described above, various additives can be used in the actinic ray curable composition of the present invention.

  The actinic ray curable ink using the actinic ray curable composition of the present invention, and the ink jet ink using the actinic ray curable ink of the present invention (hereinafter also referred to as “inkjet ink of the present invention” or “inkjet ink”). ), A colorant that can be dissolved or dispersed in the main component of the polymerizable compound can be used, but a pigment is preferred from the viewpoint of weather resistance.

  The pigments that can be preferably used in the present invention are listed below.

C. I. Pigment Yellow-1, 3, 12, 13, 14, 17, 81, 83, 87, 95, 109, 42,
C. I. Pigment Orange-16, 36, 38,
C. I. Pigment Red-5, 22, 38, 48: 1, 48: 2, 48: 4, 49: 1, 53: 1, 57: 1, 63: 1, 144, 146, 185, 101,
C. I. Pigment Violet-19, 23,
C. I. Pigment Blue-15: 1, 15: 3, 15: 4, 18, 60, 27, 29,
C. I. Pigment Green-7, 36,
C. I. Pigment White-6, 18, 21,
C. I. Pigment Black-7,
For the dispersion of the pigment, for example, a ball mill, sand mill, attritor, roll mill, agitator, Henschel mixer, colloid mill, ultrasonic homogenizer, pearl mill, wet jet mill, paint shaker, or the like can be used. It is also possible to add a dispersant when dispersing the pigment. As the dispersant, a polymer dispersant is preferably used, and examples of the polymer dispersant include Solsperse series manufactured by Avecia. Moreover, it is also possible to use a synergist according to various pigments as a dispersion aid. These dispersants and dispersion aids are preferably added in an amount of 1 to 50 parts by mass with respect to 100 parts by mass of the pigment.

  The dispersion medium is used using a solvent or a polymerizable compound, but the actinic ray curable ink used in the present invention is preferably solventless because it reacts and cures immediately after ink landing. If the solvent remains in the cured image, the solvent resistance deteriorates and the VOC of the remaining solvent arises. Therefore, it is preferable in view of dispersibility that the dispersion medium is not a solvent but a polymerizable compound, and among them, a monomer having the lowest viscosity is selected.

  The pigment is preferably dispersed so that the average particle diameter of the pigment particles is 0.08 to 0.5 μm, and the maximum particle diameter is 0.3 to 10 μm, preferably 0.3 to 3 μm. The selection of the dispersion medium, the dispersion conditions, and the filtration conditions are appropriately set. By controlling the particle size, clogging of the head nozzle can be suppressed, and ink storage stability, ink transparency, and curing sensitivity can be maintained.

  In the inkjet ink of the present invention, the color material concentration is preferably 1% by mass to 10% by mass with respect to the entire ink.

  In the present invention, a thermal base generator can also be used for the purpose of improving ejection stability and storage stability.

  Examples of the thermal base generator include compounds that release amines by decomposition by reactions such as organic acid and base salts that are decomposed by decarboxylation by heating, intramolecular nucleophilic substitution reaction, Rossen rearrangement, Beckmann rearrangement, etc. Those which cause some kind of reaction by heating and release a base are preferably used. Specifically, the salt of trichloroacetic acid described in British Patent No. 998,949, the salt of alpha-sulfonylacetic acid described in US Pat. No. 4,060,420, and the propionic acids described in JP-A-59-157737 Salts, 2-carboxycarboxamide derivatives, salts with a base component described in JP-A-59-168440 and a thermally decomposable acid using an alkali metal or an alkaline earth metal in addition to an organic base, JP-A-59-180537 Hydroxam carbamates utilizing the Lossen rearrangement described in No. 5, and aldoxime carbamates described in JP-A No. 59-195237 that generate nitriles by heating. In addition, British Patent No. 998,945, US Pat. No. 3,220,846, British Patent No. 279,480, Japanese Patent Laid-Open Nos. 50-22625, 61-32844, 61-51139, 61 The thermal base generators described in Nos. -52638, 61-51140, 61-53634 to 61-53640, 61-55644, 61-55645 and the like are useful. More specifically, guanidine trichloroacetate, methylguanidine trichloroacetate, potassium trichloroacetate, guanidine phenylsulfonylacetate, guanidine p-chlorophenylsulfonylacetate, guanidine p-methanesulfonylphenylsulfonylacetate, potassium phenylpropiolate, phenylpropiool Examples include acid guanidine, cesium phenylpropiolate, guanidine p-chlorophenylpropiolate, guanidine p-phenylene-bis-phenylpropiolate, tetramethylammonium phenylsulfonylacetate, and tetramethylammonium phenylpropiolate. The thermal base generator can be used in a wide range.

  The ink of the present invention contains an acid proliferating agent that newly generates an acid by an acid generated by irradiation with actinic rays, which is already known, including JP-A-8-248561 and JP-A-9-34106. Is also possible.

  The ink-jet ink of the present invention is produced by well dispersing the pigment together with an active energy ray-curable compound and a pigment dispersant using an ordinary dispersing machine such as a sand mill. It is preferable to prepare a concentrated solution having a high pigment concentration in advance and dilute with an active energy ray-curable compound. Sufficient dispersion is possible even with dispersion by a normal disperser, so it does not take excessive dispersion energy and does not require a great amount of dispersion time. Ink excellent in the quality is prepared. The ink is preferably filtered through a filter having a pore diameter of 3 μm or less, more preferably 1 μm or less.

[Viscosity / Other physical properties]
The actinic ray curable composition of the present invention may be used after adjusting the viscosity or the like so as to impart desired physical properties depending on the application. When the actinic ray curable composition of the present invention is used as an actinic ray curable ink or an inkjet ink using an actinic ray curable ink, it is preferable to adjust the viscosity at 25 ° C. to a high level of 7 to 40 mPa · s. An ink having a viscosity of 7 to 40 mPa · s at 25 ° C. exhibits stable ejection characteristics even from a head having a normal frequency of 4 to 10 KHz to a head having a high frequency of 10 to 50 KHz. When the viscosity is less than 5 mPa · s, a decrease in the followability of the discharge is recognized in the high-frequency head. When the viscosity exceeds 40 mPa · s, the discharge characteristic itself is obtained even if the mechanism for reducing the viscosity by heating is incorporated in the head. Drop, the stability of the discharge becomes poor, and it becomes impossible to discharge at all.

  The ink-jet ink of the present invention preferably has a conductivity of 10 μS / cm or less in a piezo head and does not cause electrical corrosion inside the head. Further, in the continuous type, it is necessary to adjust the electric conductivity by the electrolyte. In this case, it is necessary to adjust the electric conductivity to 0.5 mS / cm or more.

  In the present invention, the surface tension of the ink at 25 ° C. is preferably in the range of 25 to 40 mN / m. If the surface tension of the ink at 25 ° C. is less than 25 mN / m, stable emission is difficult to obtain, and if it exceeds 40 mN / m, a desired dot diameter cannot be obtained. Outside the range of 25 to 40 mN / m, it is difficult to obtain uniform dot diameters for various supports even when the light is emitted and irradiated with light while controlling the viscosity and moisture content of the ink as in the present invention. It becomes.

  In order to adjust the surface tension, a surfactant may be contained as necessary. Examples of the surfactant preferably used in the ink according to the present invention include anionic surfactants such as dialkylsulfosuccinates, alkylnaphthalenesulfonates, and fatty acid salts, polyoxyethylene alkyl ethers, and polyoxyethylene alkyl. Nonionic surfactants such as allyl ethers, acetylene glycols, polyoxyethylene / polyoxypropylene block copolymers, cationic surfactants such as alkylamine salts and quaternary ammonium salts, and surfactants having a polymerizable group Compound etc. are mentioned. Of these, particularly preferred are surface active compounds having a polymerizable group such as an unsaturated bond, oxirane, or oxetane ring, such as silicone-modified acrylate, fluorine-modified acrylate, silicone-modified epoxy, fluorine-modified epoxy, silicone-modified oxetane, and fluorine-modified oxetane. .

  Various additives other than those described above can be used in the ink of the present invention. For example, leveling additives, matting agents, polyester resins for adjusting film properties, polyurethane resins, vinyl resins, acrylic resins, rubber resins, and waxes can be added. In order to improve the adhesion with the recording medium, it is also effective to add a trace amount of organic solvent. In this case, it is effective to add in the range where the solvent resistance and VOC problems do not occur, and the amount used is in the range of 0.1 to 5%, preferably 0.1 to 3%. It is also possible to combine a radically polymerizable monomer and an initiator into a radical / cation hybrid type curable ink.

[Drop volume / irradiation timing / head heating]
In the image forming method of the present invention, the ink composition is ejected and drawn on a recording material by an ink jet recording method, and then the ink is cured by irradiation with an actinic ray such as ultraviolet rays.

  In the image forming method of the present invention, it is preferable that the ink is heated together with the ink jet nozzles during ink ejection so that the ink liquid has a low viscosity. As heating temperature, it is 35-100 degreeC, 35-80 degreeC, Preferably it is 35-60 degreeC.

  In the present invention, the total ink film thickness after the ink has landed and cured by irradiation with actinic rays is preferably 2 to 20 μm. In the actinic ray curable inkjet recording in the screen printing field, the total ink film thickness currently exceeds 20 μm, but in the flexible packaging printing field where the recording material is often a thin plastic material, the recording material described above is used. Not only because of curling and wrinkling problems, but also because it has the problem of changing the texture and texture of the entire printed matter. Moreover, in this invention, it is preferable that the amount of droplets discharged from each nozzle is 2 to 15 pl.

  In the present invention, in order to form a high-definition image, it is preferable that the irradiation timing is as early as possible. However, in the present invention, light irradiation is started at a timing at which the viscosity or moisture content of the ink is in a preferable state. Is preferred.

  Specifically, as the irradiation condition of the generated light, actinic light irradiation is preferably started within 0.001 to 1.0 seconds after ink landing, and more preferably 0.001 to 0.4 seconds. Also, it is preferable to terminate the light irradiation after 0.1 to 3 seconds, preferably within 0.2 to 1 second, until the ink fluidity is lost. By setting it as the above condition, enlargement of the dot diameter and bleeding between the dots can be prevented.

  As a method for irradiating actinic rays, the basic method is disclosed in JP-A-60-132767. According to this, the light source is provided on both sides of the recording head unit, and the recording head and the light source are scanned by the shuttle method. Irradiation is performed after a certain period of time after ink landing. Further, the curing is completed by another light source that is not driven. In US Pat. No. 6,145,979, as an irradiation method, a method using an optical fiber or a method of applying a collimated light source to a mirror surface provided on the side surface of a recording head unit and irradiating the recording unit with UV light is disclosed. ing. Any of these irradiation methods can be used in the image forming method of the present invention.

  In addition, irradiation with actinic rays is divided into two stages. First, actinic rays are irradiated by the above-described method within 0.001 to 1.0 seconds after ink landing, and further, actinic rays are irradiated after all printing is completed. The method is also a preferred embodiment. By dividing the irradiation of actinic rays into two stages, it is possible to further suppress the shrinkage of the recording material that occurs during ink curing.

Examples of light sources used for actinic ray irradiation include mercury arc lamps, xenon arc lamps, fluorescent lamps, carbon arc lamps, tungsten-halogen copying lamps, high pressure mercury lamps, metal halide lamps, electrodeless UV lamps, low pressure mercury lamps, UV There are lasers, xenon flash lamps, insect traps, black lights, germicidal lamps, cold cathode tubes, LEDs, etc. Among them, fluorescent tubes are preferred because of their low energy and low cost, but the present invention is not limited to these. . As the light source wavelength, a light source having an emission wavelength peak at 200 to 400 nm is preferable in terms of sensitivity. The illuminance is 1 to 3000 mW / cm ² , preferably 1 to 200 mW / cm ² .

  The inkjet ink of the present invention is used to print an image on a recording medium (also referred to as a base material). As the recording medium, all of a wide range of conventional synthetic resins used in various applications are used. Specific examples include polyester, polyvinyl chloride, polyethylene, polyurethane, polypropylene, acrylic resin, polycarbonate, polystyrene, acrylonitrile-butadiene-styrene copolymer, polyethylene terephthalate, polybutadiene terephthalate, and the like. The thickness and shape of the synthetic resin base material are not limited at all.

  As a base material that can be used in the present invention, a non-absorbent support can be used in addition to normal uncoated paper, coated paper, etc. Among them, a non-absorbent support is used as the base material. It is preferable.

  In the present invention, various non-absorbing plastics and films thereof can be used as the non-absorbing support. Examples of the various plastic films include PET film, OPS film, OPP film, ONy film, and PVC film. , PE film, and TAC film. As other plastics, polycarbonate, acrylic resin, ABS, polyacetal, PVA, rubbers and the like can be used. Moreover, it is applicable also to metals and glass. Among these recording materials, the structure of the present invention is effective particularly when an image is formed on a PET film, an OPS film, an OPP film, an ONy film, or a PVC film that can be shrunk by heat. These substrates are not only susceptible to curling and deformation of the film due to ink curing shrinkage and heat generation during the curing reaction, but also the ink film is difficult to follow the substrate shrinkage.

  The surface energies of these various plastic films differ greatly, and it has been a problem in the past that the dot diameter after ink landing varies depending on the recording material. The constitution of the present invention includes an OPP film having a low surface energy, an OPS film, and a PET having a relatively large surface energy, but the substrate preferably has a wetting index of 40 to 60 mN / m.

  In the present invention, it is more advantageous to use a long (web) recording material in terms of the cost of the recording material such as packaging cost and production cost, the production efficiency of the print, and the ability to cope with printing of various sizes. is there.

Example 1
A compound represented by the general formula (1) or a comparative compound, a cationic polymerizable compound, and other photoacid generators were mixed as shown in Tables 1 and 2 to prepare actinic ray curable compositions 1 to 36.

  The compounds used are shown below.

<Polymerizable compound 1>
Celoxide 2021P: manufactured by Daicel Chemical Industries, Ltd. Celoxide 3000: manufactured by Daicel Chemical Industries, Ltd. <polymerizable compound 2>
OXT-101: Toagosei Co., Ltd. OXT-212: Toagosei Co., Ltd. OXT-221: Toagosei Co., Ltd. (photopolymerization initiator)
TAG-382: Ion type compound having sulfonium cation (manufactured by Toyo Ink Manufacturing Co., Ltd.)
Using the obtained actinic ray curable compositions 1 to 36, a curing test was performed as follows, and the evaluation results are shown in Tables 3 and 4.

(Curing of actinic ray curable composition)
The actinic ray curable composition shown in Tables 1 and 2 was applied to a PET film so as to have a thickness of 3 μm. Irradiation was performed within 2 seconds using a 3 kW power source as a light source. At this time, a Pyrex (registered trademark) glass plate having a thickness of 2 mm was used as a filter, and light having a wavelength of 300 nm or less was cut.

  The curing test was performed three times each under a low humidity condition of 30% humidity and a high humidity condition of 70% humidity, and the light source distances were 10 cm, 5 cm, and 3 cm, respectively.

(Evaluation of curability)
After 5 minutes from irradiation with actinic light, the surface of the cured product was strongly rubbed with Kimwipe and visually observed.

◎: Cured sufficiently at 10 cm (Kimwipe does not have a cured product component) ○: Not cured sufficiently at 10 cm, but cured sufficiently at 5 cm △: Not cured sufficiently at 5 cm, but sufficient at 3 cm Curing ×: Thing that does not cure sufficiently even at 3 cm ◎, ○, Δ are at a level where there is no practical problem.

(Evaluation of storage stability)
<Precipitation of solid>
The actinic ray curable compositions shown in Tables 1 and 2 were sealed in a sealed glass container, stored at −10 ° C. for 2 months, and the inside of the container was visually observed.

A: No solid precipitation is observed. O: Solid precipitation is hardly observed. X: Solid precipitation is clearly observed.

<Coloring>
The actinic ray curable compositions of Tables 1 and 2 were sealed in a sealed polypropylene bottle and stored at 70 ° C. for 4 days. Compared to the initial composition,
A: No discoloration is observed at all. B: Almost no discoloration is observed. X: Discoloration is clearly observed.

[Evaluation of cured product]
The physical properties and storage stability were evaluated using a cured product that was cured by irradiation with actinic rays under the same conditions as in the above-described curing test except that the light source distance was set to 2 cm.

(Evaluation of substrate adhesion)
Cello tape (registered trademark) was applied in the range of 2 cm × 1 cm square of the cured product and strongly pressed, peeled off perpendicularly to the surface of the cured product, and the state of the subsequent cured product was visually observed.

A: The cured product is not peeled off from the substrate at all. ○: A part is peeled off. X: Most part is peeled off.

(Evaluation of flexibility)
The cured product was completely folded in two, and the state of the cured product thereafter was visually observed.

◎: No streaks appear in the folded part ○: Streaks appear in a part of the folded part △: Streaks remain in the entire folded part ×: The folded part is cracked ◎, ○ is practical There is no problem level and Δ is a usable level.

(Evaluation of scratch strength)
Using a pencil of HB, a certain force was applied, and a 3 cm straight line was quickly drawn on the surface of the cured product three times, and the surface was visually observed.

◎: All three drawn lines are not damaged ○: One of the three lines is damaged within 5mm △: Two of the three lines are damaged within 5mm Or, one of the three lines has scratches exceeding 5 mm ×: all three lines have scratches, or two of the three lines have scratches exceeding 5 mm ◎, ○ A practically acceptable level, Δ is a usable level.

(Evaluation of curl)
The state of the cured product after 5 minutes of the curing test was visually observed.

A: The film is not curled at all. B: The edge is partially curled. X: The curl is greatly curled over the whole.

(Evaluation of storage stability)
The cured product was stored at 70 ° C. for 4 days.

<Coloring>
Compare the cured product after storage with the cured product in the initial state.
A: No discoloration is observed at all. B: Almost no discoloration is observed. X: Discoloration is clearly observed.

<Odor>
A: The smell of the cured product after storage is smelled and there is no odor. O: The odor is slightly felt. X: Obvious odor. A, O is a level having no practical problem.

  As is apparent from Tables 3 and 4, the actinic ray curable composition of the present invention has extremely good curability by long-wavelength light irradiation, storage stability of the composition, and substrate adhesion of the cured product. Recognize.

Example 2
<Ink composition>
5 parts by mass of a dispersant (PB822 manufactured by Ajinomoto Fine Techno Co., Ltd.) and each photopolymerizable compound shown in Table 3 were put into a stainless beaker and stirred and mixed for 1 hour while heating on a hot plate at 65 ° C. And dissolved. Next, after adding 3 parts by mass of the following various pigments to this solution, it was sealed in a plastic bottle together with 200 g of zirconia beads having a diameter of 1 mm, and subjected to dispersion treatment for 2 hours using a paint shaker. Next, the zirconia beads are removed, and various additives such as photoacid generators, photopolymerization initiators, basic compounds, and surfactants are added in combinations shown in Tables 5 and 6 to prevent clogging of the printer. Therefore, the ink composition was prepared by filtration through a 0.8 μm membrane filter. The above operation was performed for each color of K, C, Y, M, and W to prepare ink composition sets 101 to 138.

  The following pigments were used.

K: C.I. I. Pigment Black-7
C: C.I. I. Pigment Blue-15: 3
M: C.I. I. Pigment Red-57: 1
Y: C.I. I. Pigment Yellow-13
W: Titanium oxide (anatase type: particle size 0.2 μm)

  The compounds used are shown below.

(Photopolymerization initiator)
UVI6992: Dow Chemical Company Propion Carbonate 50% solution (basic compound)
Basic compound A: N-ethyldiethanolamine (surfactant)
F1405: Megafax F1405 Perfluoroalkyl group-containing ethylene oxide adduct (manufactured by Dainippon Ink & Chemicals, Inc.)
(Compatibilizer)
145P: Halitack 145P (Rosin-modified maleic resin, Harima Chemical Co., Ltd.)
<< Inkjet image forming method >>
Image forming method A (no filter)
Each ink composition set 101 to 138 prepared above is loaded into an ink jet recording apparatus equipped with a piezo type ink jet nozzle, and the recording material is 600 mm wide and 20 m long (synthetic paper YUPO FGS manufactured by YUPO Corporation). The following image recording was performed continuously. The ink supply system was composed of an ink tank, a supply pipe, a front chamber ink tank immediately before the head, a pipe with a filter, and a piezo head. The ink was insulated from the front chamber tank to the head portion and heated at 50 ° C. In addition, the head portion is heated according to the viscosity of each curable composition ink, and multi-size dots having a droplet amount of 2 to 15 pl are set to 720 × 720 dpi (where dpi is the number of dots per inch, that is, 2.54 cm). The cured composition ink described above was continuously ejected by being driven so as to be ejected at a resolution of (represented). The recording material was heated to 50 ° C. by a surface heater. After landing, it was cured instantaneously (less than 0.5 seconds after landing) with an irradiation light source (metal halide lamp) on both sides of the carriage (MAL400NL power: 3 kW · hr 120 W / cm, manufactured by Nippon Batteries Co., Ltd.). When the total ink film thickness was measured after image recording, it was in the range of 2.3 to 13 μm. The inkjet image was formed by printing in an environment of 30 ° C./80% RH and 25 ° C./20% RH according to the above method.

  In addition, the illumination intensity of each irradiation light source measured the integrated illumination intensity of 254 nm using UVPF-A1 by Iwasaki Electric Co., Ltd.

Image forming method B (with filter)
An image was formed in the same manner as in the image forming method A, except that one Pyrex (registered trademark) glass having a thickness of 1 mm was used as a filter (wavelength of 300 nm or less was substantially cut) during exposure.

[Evaluation of inkjet recording image]
Each image recorded by the above image forming method was subjected to the following evaluations.

(Character quality)
A 6-point MS Mincho type character was printed at the target density, and the character roughness was magnified with a loupe, and the character quality was evaluated according to the following criteria.

◎: No rusting ○: Slight rustling is visible △: Gashesiness is visible, but it can be recognized as characters and can be used at the last minute ×: Levels that are harsh and characters are faint and cannot be used.

(Mixed colors (bleeds, wrinkles))
Print at 720 dpi so that each dot of each color Y, M, C, K, W is adjacent to each other, enlarge each adjacent color dot with a loupe, visually observe the state of bleeding and wrinkles, and mix colors according to the following criteria Was evaluated.

◎: Adjacent dot shape keeps perfect circle and no blur ○: Adjacent dot shape keeps almost perfect circle and almost no blur △: Adjacent dots are slightly blurred and dot shape is slightly displaced , The level that can be used at the end ×: The level where the adjacent dots are blurred and mixed, and there is a wrinkle in the overlapping part, so it cannot be used.

(Evaluation of ink storage stability 1)
The prepared ink composition was put into a sealed container for each color and stored at room temperature for 1 month in a dark place. Then, image formation and tests similar to those described above were performed to determine storage stability.

○: No significant change in test results even after storage for 1 month △: A large change was observed in one or more items in any test ×: Ink viscosity increased and image formation failed ○ is storage stability with no practical problem.

(Evaluation of ink storage stability 2)
Among the ink compositions prepared, yellow ink was sealed in a glass sample tube, stored at −20 ° C. for 1 week, filtered through a filter paper having a retained particle diameter of 3 μm, and the residue on the filter paper was visually confirmed. .

◯: No precipitation was confirmed Δ: Slight precipitation was confirmed ×: Clear precipitation was confirmed ○ is a level having no practical problem.

(Evaluation of substrate adhesion of ink cured film)
Cellotape (registered trademark) was applied in the range of 2 cm × 1 cm square of the ink cured film and strongly pressure-bonded, quickly peeled perpendicularly to the ink cured film surface, and the state of the ink cured film thereafter was visually observed.

◯: The ink cured film is not peeled off from the substrate at all. Δ: Partly peeled off. X: Most part is peeled off.

  From the results of Tables 7 and 8, it can be seen that the sample of the present invention has high image quality and excellent storage stability, and exhibits good curability regardless of environmental differences. It turns out that the sample of this invention is excellent in base-material adhesiveness.

Claims (9)

An actinic ray curable composition comprising at least one compound represented by the following general formula (1) and at least one cationically polymerizable compound.

(In the formula, R ₁ , R ₂ and R ₄ are substituents, and m, n and p each represents an integer of 0 to _4. X is a divalent linking group which is a single bond or the following moiety. R ₃ is any group selected from the structural formula group (A-1), R ₃ is any group selected from the following partial structural formula group (B-1), and Z ⁻ represents a counter anion. .)

(In the formula, * part represents a bonding site. R ₅ represents a hydrogen atom or a substituent. K represents an integer of 1 to 6.)

(In the formula, * part is a bonding site. R _A represents a substituent, Alk represents an unsubstituted alkyl group or an unsubstituted cycloalkyl group, Ar represents a substituted or unsubstituted aryl group, and H _Ar represents Represents a substituted or unsubstituted heteroaryl group, R ₆ represents a hydrogen atom or a substituent, a bond whose terminal is drawn inside the ring structure is bonded to any carbon atom on the ring, and t Is an integer from 0 to 11.) The actinic ray curable composition according to claim 1, wherein X in the general formula (1) is any one of a single bond, a sulfur atom, and a carbonyl group. The actinic ray curable composition according to claim 2, wherein X in the general formula (1) is a carbonyl group. R ₁ and R _{2 in} the general formula (1) are each independently a halogen atom, an alkyl group, an alkoxy group, an alkylthio group, or an alkylamino group, and R ₄ is a halogen atom, a hydroxyl group, or an alkyl group. , An alkoxy group, an alkylthio group, an alkylamino group, and in the partial structural formula group (A-1), R ₅ is a hydrogen atom, an alkyl group, an aryl group, an acyl group, or any hydrogen atom. The atoms are removed to form a linking group and bond to any carbon atom of the general formula (1) to form a ring structure, and R _{A of the} partial structural formula group (B-1) is a halogen atom, an alkyl group, an alkoxy group group, an alkylthio group, or an alkylamino group, R ₆ is a hydrogen atom or an alkyl group, an aryl group, or, or any linking group removed a hydrogen atom of the acyl group It is in any radiation curable composition according to any one of claims 1 to 3, characterized in that it constitutes a ring structure with the carbon atoms of the general formula (1). The actinic ray curable composition according to any one of claims 1 to 4, wherein the cationically polymerizable compound is an alicyclic epoxy compound represented by the following general formula (C).

(Wherein R ₂₀₁ and R ₂₀₂ each independently represents a halogen atom, an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, an acyl group, an acyloxy group, an alkoxycarbonyl group, m20, n20 represents 0, 1 or 2. r0 represents 1 to 3. L ₀ represents an r0 + 1-valent linking group or a single bond having 1 to 15 carbon atoms which may contain an oxygen atom or a sulfur atom in the main chain. ) An actinic ray curable ink comprising the actinic ray curable composition according to any one of claims 1 to 5. A curing method for an actinic radiation curable composition, wherein the actinic radiation curable composition according to any one of claims 1 to 5 is cured by irradiating the actinic radiation. A method of curing an actinic radiation curable ink, wherein the actinic radiation curable ink according to claim 6 is cured by irradiation with an actinic ray. An image forming method, wherein the actinic ray curable ink according to claim 6 is ejected imagewise onto a recording material from an ink jet recording head, and printing is performed on the recording material.