JP2006152064A - Active ray-curable composition, active ray-curable ink-jet ink, image-forming method and ink-jet recording apparatus using the ink - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an active ray-curable composition and an active ray-curable ink-jet ink capable of forming strong coating films having high flexibility, and to provide an active ray-curable ink-jet ink producing no wrinkles even when thick films are cured, an image-forming method and an ink-jet recording apparatus. <P>SOLUTION: The active ray-curable composition comprises a radically polymerizable monomer as a photopolymerizable compound and an inorganic oxide colloid. Alternatively, the active ray-curable composition comprises a compound having an oxetane ring and an epoxy compound as a photopolymerizable compound, a photo acid generator and an inorganic oxide colloid. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an actinic ray curable composition, an actinic ray curable ink jet ink, an image forming method, and an ink jet recording apparatus, which are cured with low viscosity and high sensitivity, and the formed coating film has excellent adhesion and hardness. About.

  Conventionally, curable compositions that are cured by active energy rays such as ultraviolet rays and electron beams or heat are various kinds of paints, adhesives, printing inks, printed circuit boards, and electrical insulation relations such as plastic, paper, woodwork and inorganic materials. Has been put to practical use. In recent years, printing inks, paints, adhesives and the like have been desired to further improve weather resistance and adhesion. Ink jet inks using these include ultraviolet curable jet inks that are cured by ultraviolet rays. This inkjet system using ultraviolet curable ink has been attracting attention in recent years because it has a relatively low odor and can be recorded on a recording medium having no quick drying and no ink absorbability, and an ultraviolet curable inkjet ink has been disclosed. (See, for example, Patent Documents 1 and 2).

Inks using radically polymerizable compounds are subject to an oxygen inhibiting action, and therefore, when the amount of ink droplets is small, curing inhibition tends to occur. Ink using a cationically polymerizable compound does not have an oxygen inhibition effect, but has a problem that it is easily affected by moisture (humidity) at a molecular level (see, for example, Patent Documents 3 to 6).
In this field, the film to be formed is required to be strong and flexible and to have good adhesion.

  Further, improvement in productivity, that is, improvement in printing speed is also demanded. Although the printing speed is increased by increasing the ink discharge amount per time, when the ink discharge amount is increased, that is, when UV curing is performed with a thick ink film, fine wrinkles are generated on the surface. It was newly found that the physical properties of the cured film may be deteriorated.

Although it is disclosed that silica fine particles are added to ink-jet ink (see, for example, Patent Documents 7 and 8), both are inks mainly composed of water, and the purpose thereof is wear resistance and printing characteristics. There is no description on improvement of wrinkles during thick film curing as in the present invention.
JP-A-6-200204 Special Table 2000-504778 JP 2001-220526 A (Claims, Examples) JP 2002-188025 A (Claims, Examples) JP 2002-317139 A (Claims, Examples) JP 2003-55449 A (Claims, Examples) JP 2000-53901 A (Claims, Examples) Japanese Patent Laid-Open No. 10-287035 (Claims, Examples)

  The present invention has been made in view of the above problems, and an object of the present invention is to provide an actinic ray curable composition and an actinic ray curable inkjet ink capable of forming a highly sensitive, flexible and strong coating film. Furthermore, another object of the present invention is to provide an actinic ray curable inkjet ink, an image forming method, and an inkjet recording apparatus that do not generate wrinkles even during thick film curing.

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

(Claim 1)
An actinic ray curable composition containing a radical polymerizable monomer as a photopolymerizable compound and an inorganic oxide colloid.

(Claim 2)
An actinic ray curable composition comprising a compound having an oxetane ring and an epoxy compound as a photopolymerizable compound, and a photoacid generator and an inorganic oxide colloid.

(Claim 3)
The actinic ray curable composition according to claim 1 or 2, wherein the inorganic oxide colloid is colloidal silica or alumina colloid.

(Claim 4)
The actinic ray curable composition according to any one of claims 1 to 3, which does not contain 5% or more of water.

(Claim 5)
The photoacid generator is at least one of sulfonium salts represented by the following general formulas (1) to (4) that do not generate benzene by actinic ray irradiation. Item 4. The actinic ray curable composition according to item.

[Wherein R _{S1 to} R _S17 each represents a hydrogen atom or a substituent, R _{S1 to} R _S3 do not simultaneously represent a hydrogen atom, and R _{S4 to} R _S7 do not represent a hydrogen atom at the same time, R _{S8 to} R _S11 do not represent hydrogen atoms at the same time, and R _{S12 to} R _S17 do not represent hydrogen atoms at the same time. X represents a non-nucleophilic anionic residue. ]
(Claim 6)
6. The actinic ray according to claim 5, wherein the sulfonium salt represented by the general formulas (1) to (4) is at least one of sulfonium salts selected from the following general formulas (5) to (13). A curable composition.

[Wherein, X represents a non-nucleophilic anion residue having the same meaning as in the general formulas (1) to (4). ]
(Claim 7)
The actinic ray curable composition according to any one of claims 2 to 6, wherein the compound having an oxetane ring is a disubstituted oxetane compound.

(Claim 8)
The actinic ray curable composition according to any one of claims 2 to 6, wherein the epoxy compound is an epoxidized fatty acid ester or an epoxidized fatty acid glyceride.

(Claim 9)
The actinic ray curable composition according to any one of claims 2 to 6, wherein the epoxy compound is an alicyclic epoxy compound.

(Claim 10)
An actinic ray curable composition, wherein the alicyclic epoxy compound is a compound represented by the following general formula (A).

Wherein, R ₁₀₀ represents a substituent, m0 represents 0-2. r0 represents 1-3. L ₀ represents a C 1-15 r 0 + 1 valent linking group or single bond that may contain an oxygen atom or a sulfur atom in the main chain. ]
(Claim 11)
The alicyclic epoxy compound represented by the general formula (A) is selected from at least one of the alicyclic epoxy compounds represented by the following general formula (I), (II), (III) or (IV) An actinic ray curable composition, which is characterized by

[Wherein R ₁₀₁ represents a substituent, and m1 represents 0 to 2. 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. ]

[Wherein, R ₁₀₂ represents a substituent, and m2 represents 0 to 2. r2 represents 1-3. L ₂ represents a C 1-15 r 2 + 1 valent linking group or single bond which may contain an oxygen atom or a sulfur atom in the main chain. ]

[Wherein, R ₂₀₀ represents an aliphatic group other than the α and β positions of the oxirane ring, and m3 represents 0 to 2. X ₁ represents — (CH ₂ ) _n0 — or — (O) _n0 —, and n0 represents 0 or 1. p1 and q1 each represents 0 or 1, and are not 0 at the same time. r3 represents 1-3. L ₃ represents a linking group or a single bond having an R ₃ + 1 valent branched structure having 1 to 15 carbon atoms, which may contain an oxygen atom or a sulfur atom in the main chain. ]

[Wherein, R ₂₀₁ represents an aliphatic group other than the α and β positions of the oxirane ring, and m4 represents 0 to 2. X ₂ represents — (CH ₂ ) _n1 — or — (O) _n1 —, and n1 represents 0 or 1. p2 and q2 each represent 0 or 1, and are not 0 at the same time. r4 represents 1-3. L ₄ represents a linking group or a single bond having an r4 + 1-valent branched structure having 1 to 15 carbon atoms, which may contain an oxygen atom or a sulfur atom in the main chain. ]
(Claim 12)
The actinic ray curable composition according to any one of claims 1 to 11, wherein the viscosity at 25 ° C is 7 to 40 mPa · s.

(Claim 13)
The actinic ray curable inkjet ink according to claim 1, wherein the actinic ray curable composition according to claim 1 contains a pigment.

(Claim 14)
14. An image forming method in which the actinic radiation curable inkjet ink according to claim 13 is jetted onto a recording material from an inkjet recording head, and printing is performed on the recording material, after the actinic radiation curable inkjet ink has landed. Irradiating actinic rays for 0.001 to 1.0 seconds.

(Claim 15)
An image forming method in which the actinic ray curable ink-jet ink according to claim 13 is jetted onto a recording material from an ink-jet recording head, and printing is performed on the recording material, the minimum being ejected from each nozzle of the ink-jet recording head An image forming method, wherein the ink droplet amount is 2 to 15 pl.

(Claim 16)
The inkjet recording apparatus used for the image forming method according to claim 14 or 15, wherein the inkjet recording apparatus includes an actinic ray curable inkjet ink and an inkjet recording head that are heated to 35 ° C to 100 ° C and then discharged. apparatus.

(Claim 17)
The inkjet recording apparatus used for the image forming method of Claim 14 or 15 has a mechanism which discharges actinic-light curable inkjet ink to the recording medium heated at 35-60 degreeC.

  According to the present invention, an actinic ray curable composition that can form a highly sensitive, flexible, and strong coating film and that does not generate wrinkles even during thick film curing (hereinafter simply referred to as a curable composition). And actinic ray curable inkjet ink (hereinafter also simply referred to as inkjet ink or ink), an image forming method, and an inkjet recording apparatus.

The present invention will be described in more detail. Examples of the inorganic oxide colloid that can be preferably used in the present invention include colloidal silica and alumina colloid. These are generally colloidal solutions in which ultrafine particles such as SiO ₂ and Al ₂ O ₃ are dispersed in water or an organic solvent. As a commercially available inorganic oxide colloid, the dispersion medium is water, methanol, 2-propanol, n-propanol, xylene or the like, and the particle diameter of particles such as SiO ₂ and Al ₂ O ₃ is 5 to 100 nm. Things are common. In many cases, the pH of the inorganic oxide colloid solution is adjusted to be acidic or alkaline rather than neutral. This is because the stable dispersion region of the inorganic oxide colloid exists on the acidic side or the alkaline side. When added to the actinic ray curable inkjet ink, the pH of the stable dispersion region of the inorganic oxide colloid and the ink It is necessary to add in consideration of pH.

  The addition amount of the inorganic oxide colloid of the present invention to the actinic ray curable composition or the actinic ray curable inkjet ink is preferably 0.1 to 15% by mass, and two or more additions are also possible. Is possible. If it is less than 0.1%, the effect is small, and if it is 15% or more, the ejection property may be deteriorated.

In the present invention, “does not generate benzene by actinic ray irradiation” means that benzene is not substantially generated. Specifically, the ink composition contains 5% by mass of an onium salt (photoacid generator). Using ink, an image of about 100 m ² is printed with a thickness of 15 μm, and the amount of benzene generated when irradiated with an actinic ray in an amount sufficient to decompose the photoacid generator with the ink film surface kept at 30 ° C. It means that the amount is very little or less than 5 μg. The onium salt is preferably a sulfonium salt or an iodonium salt, and satisfies the above conditions as long as it has a substituent on the benzene ring bonded to S ⁺ or I ⁺ . The sulfonium salt is preferably a sulfonium salt compound represented by the above general formulas (1) to (4), and satisfies the above conditions as long as it has a substituent on the benzene ring bonded to S ⁺ .

In the general formulas (1) to (4), R _{S1 to} R _S17 each represent a hydrogen atom or a substituent. However, R _{S1 to} R _S3 do not represent hydrogen atoms at the same time, R _{S4 to} R _S7 do not represent hydrogen atoms at the same time, R _{S8 to} R _S11 do not represent hydrogen atoms at the same time, R _S12 to R R _S17 does not represent a hydrogen atom at the same time.

As the substituent represented by R _{S1 to} R _S17 , an alkyl group such as methyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group, t-butyl group, pentyl group, hexyl group, Group, ethoxy group, propyl group, butoxy group, hexyloxy group, decyloxy group, dodecyloxy group, alkoxy group, acetoxy group, propionyloxy group, decylcarbonyloxy group, dodecylcarbonyloxy group, methoxycarbonyl group, ethoxycarbonyl group , A carbonyl group such as a benzoyloxy group, a phenylthio group, a halogen atom such as fluorine, chlorine, bromine and iodine, a cyano group, a nitro group and a hydroxyl group.

X represents a non-nucleophilic anion residue. For example, halogen atoms such as F, Cl, Br, and I, B (C ₆ F ₅ ) ₄ , R ₁₈ COO, R ₁₉ SO ₃ , SbF ₆ , AsF ₆ , PF ₆ , BF _{4 and the} like. R ₁₈ and R ₁₉ are each an alkyl group such as a methyl group, an ethyl group, a propyl group or a butyl group, a halogen atom such as fluorine, chlorine, bromine or iodine, a nitro group, a cyano group, a methoxy group or an ethoxy group. An alkyl group or a phenyl group which may be substituted with an alkoxy group or the like is represented. Among these, B (C ₆ F ₅ ) ₄ and PF ₆ are preferable from the viewpoint of safety.

  The above compounds can be obtained from THE CHEMICAL SOCIETY OF JAPAN Vol. 71 no. It can be easily synthesized by a known method in the same manner as the photoacid generator described in 11, 1998, Organic Electronics Materials Research Group, “Organic Materials for Imaging”, Bunshin Publishing (1993).

  In the present invention, the sulfonium salt represented by the general formulas (1) to (4) is particularly preferably at least one of the sulfonium salts selected from the general formulas (5) to (13). X represents a non-nucleophilic anion residue and is the same as described above.

Illustrative compounds including iodonium salts include the following compounds in addition to X = PF _{6 in} the formulas (5) to (13).

  The radical polymerizable monomer according to the present invention is a compound having an ethylenically unsaturated bond capable of radical polymerization, and any compound having at least one ethylenically unsaturated bond capable of radical polymerization in the molecule. However, those having chemical forms such as monomers, oligomers and polymers are included. Only one type of radically polymerizable monomer may be used, or two or more types may be used in combination at an arbitrary ratio in order to improve the desired properties.

  Examples of compounds having an ethylenically unsaturated bond capable of radical polymerization include unsaturated carboxylic acids such as acrylic acid, methacrylic acid, itaconic acid, crotonic acid, isocrotonic acid, maleic acid and their salts, esters, urethanes, amides. And radically polymerizable compounds such as various unsaturated polyesters, unsaturated polyethers, unsaturated polyamides and unsaturated urethanes. Specifically, 2-ethylhexyl acrylate, 2-hydroxyethyl acrylate, butoxyethyl acrylate, carbitol acrylate, cyclohexyl acrylate, tetrahydrofurfuryl acrylate, benzyl acrylate, bis (4-acryloxypolyethoxyphenyl) propane, neopentyl glycol Diacrylate, 1,6-hexanediol diacrylate, ethylene glycol diacrylate, diethylene glycol diacrylate, triethylene glycol diacrylate, tetraethylene glycol diacrylate, polyethylene glycol diacrylate, polypropylene glycol diacrylate, pentaerythritol triacrylate, pentaerythritol Tetraacrylate, dipentaery Acrylic acid derivatives such as lithol tetraacrylate, trimethylolpropane triacrylate, tetramethylolmethane tetraacrylate, oligoester acrylate, N-methylol acrylamide, diacetone acrylamide, epoxy acrylate, methyl methacrylate, n-butyl methacrylate, 2-ethylhexyl methacrylate , Lauryl methacrylate, allyl methacrylate, glycidyl methacrylate, benzyl methacrylate, dimethylaminomethyl methacrylate, 1,6-hexanediol dimethacrylate, ethylene glycol dimethacrylate, triethylene glycol dimethacrylate, polyethylene glycol dimethacrylate, polypropylene glycol dimethacrylate, trimethylol Methacryl derivatives such as tan trimethacrylate, trimethylolpropane trimethacrylate, 2,2-bis (4-methacryloxypolyethoxyphenyl) propane, and other derivatives of allyl compounds such as allyl glycidyl ether, diallyl phthalate, triallyl trimellitate More specifically, Shinzo Yamashita, “Cross-linking agent handbook”, (1981 Taiseisha); Kato Kiyomi, “UV / EB curing handbook (raw material)” (1985, Polymer publication) ); Radtech Study Group, “Application and Market of UV / EB Curing Technology”, 79 pages, (1989, CMC); Eiichiro Takiyama, “Polyester Resin Handbook”, (1988, Nikkan Kogyo Shimbun) Commercially available products described in the above, or radically polymerizable or crosslinkable monomers known in the industry -Oligomers and polymers can be used. The amount of the radical polymerizable compound added is preferably 1 to 97% by mass, more preferably 30 to 95% by mass.

  Examples of the radical polymerization initiator include triazine derivatives described in JP-B-59-1281, JP-A-69-1621, and JP-A-60-60104, JP-A-59-1504 and JP-A-61-2243807. And other publications such as JP-B Nos. 43-23684, 44-6413, 44-6413, and 47-1604, and US Pat. No. 3,567,453. Diazonium compounds described in the specification, organic azide compounds described in U.S. Pat. Nos. 2,848,328, 2,852,379 and 2,940,853, Japanese Patent Publication No. 36-22062, Ortho-quinonediazides described in JP-A-37-13109, JP-A-38-18015, JP-A-45-9610, JP-B-55-39162, JP-A-59-1 No. 023 etc. and various onium compounds described in “Macromolecules, Vol. 10, Volume 1307 (1977)”, azo compounds described in JP-A-59-142205, 1-54440, European Patent Nos. 109,851 and 126,712, “Journal of Imaging Science” (J. Imag. Sci.), Vol. 30, No. 174 Page (1986), metal allene complexes described in JP-A-4-213861 and JP-A-4-255347, organoboron complexes described in JP-A-4-151197, and titanocene described in JP-A-61-151197. "Coordination Chemistry Review" try Review) ", Vol. 84, pages 85-277 (1988) and transition metal complexes containing transition metals such as ruthenium described in JP-A-2-182701, JP-A-3-209477 Examples include 2,4,5-triarylimidazole dimer, carbon tetrabromide, and organic halogen compounds described in JP-A-59-107344. These polymerization initiators are preferably contained in the range of 0.01 to 10 parts by mass with respect to 100 parts by mass of the compound having an ethylenically unsaturated bond capable of radical polymerization.

  The compound having an oxetane ring according to the present invention will be described below.

(Oxetane compound having an oxetane ring substituted at the 2-position)
In the actinic ray curable composition of the present invention, it is preferable to use an oxetane compound having at least one oxetane ring substituted at the 2-position represented by the following general formula (14) in the molecule.

In the general formula (14), R _{1 to} R ₆ each represent a hydrogen atom or a substituent. However, at least one of the groups represented by R _{3 to} R ₆ is a substituent. In the general formula (14), examples of the substituent represented by R _{1 to} R ₆ include a fluorine atom and an alkyl group having 1 to 6 carbon atoms (for example, a methyl group, an ethyl group, a propyl group, or a butyl group). ), A C1-C6 fluoroalkyl group, an allyl group, an aryl group (for example, a phenyl group, a naphthyl group, etc.), a furyl group, or a thienyl group. Moreover, these groups may further have a substituent.

(Oxetane compound having one oxetane ring in the molecule)
Furthermore, among the general formula (14), compounds having an oxetane ring represented by the following general formulas (15) to (18) are preferably used.

In the formula, R _{1 to} R ₆ each represent a hydrogen atom or a substituent, R ₇ and R ₈ each represent a substituent, and Z independently represents an oxygen or sulfur atom, or contains an oxygen or sulfur atom in the main chain. The divalent hydrocarbon group which may be sufficient. In the general formula (15) to (18), the substituent represented by R ₁ to R ₆ have the same meanings as the substituents represented by R ₁ to R ₆ in the general formula (14).

In the general formulas (15) to (18), the substituent represented by R ₇ or R ₈ is an alkyl group having 1 to 6 carbon atoms (for example, a methyl group, an ethyl group, a propyl group, or a butyl group). An alkenyl group having 1 to 6 carbon atoms (for example, 1-propenyl group, 2-propenyl group, 2-methyl-1-propenyl group, 2-methyl-2-propenyl group, 1-butenyl group, 2-butenyl group) Or a 3-butenyl group), an aryl group (for example, a phenyl group, a naphthyl group, etc.), an aralkyl group (for example, a benzyl group, a fluorobenzyl group, a methoxybenzyl group, etc.), an acyl group having 1 to 6 carbon atoms (for example, , A propylcarbonyl group, a butylcarbonyl group or a pentylcarbonyl group), an alkoxycarbonyl group having 1 to 6 carbon atoms (for example, an ethoxycarbonyl group, a propoxycarbonyl group). Group, butoxycarbonyl group etc.), represents the number 1-6 alkylcarbamoyl group having a carbon (e.g., propylcarbamoyl group, butyl pentylcarbamoyl group), alkoxy carbamoyl group (e.g., such as ethoxy carbamoyl groups).

  In the general formulas (15) to (18), an oxygen or sulfur atom represented by Z or a divalent hydrocarbon group which may contain an oxygen or sulfur atom in the main chain is an alkylene group (for example, ethylene Group, trimethylene group, tetramethylene group, propylene group, ethylethylene group, pentamethylene group, hexamethylene group, heptamethylene group, octamethylene group, nonamethylene group, decamethylene group, etc.), alkenylene group (for example, vinylene group, propenylene group) Etc.) and alkynylene groups (for example, ethynylene group, 3-pentynylene group, etc.), and the carbon atom of the alkylene group, alkenylene group or alkynylene group may be replaced by an oxygen atom or a sulfur atom.

Among the above substituents, R ₁ is preferably a lower alkyl group (eg, a methyl group, an ethyl group, a propyl group, etc.), and an ethyl group is particularly preferably used. R ₇ and R ₈ are preferably a propyl group, a butyl group, a phenyl group or a benzyl group, and Z is preferably a hydrocarbon group containing no oxygen or sulfur atom (an alkylene group, an alkenylene group, an alkynylene group or the like).

(Compound having two or more oxetane rings in the molecule)
In the present invention, a compound having two or more oxetane rings in a molecule represented by the following general formulas (19) and (20) can be used.

In the formula, Z is synonymous with the group used in the general formulas (15) to (18), and m represents 2, 3 or 4. R _{1 to} R ₆ are a hydrogen atom, a fluorine atom, an alkyl group having 1 to 6 carbon atoms (for example, methyl group, ethyl group, propyl group, butyl group, etc.), a fluoroalkyl group having 1 to 6 carbon atoms, allyl Represents a group, an aryl group (for example, a phenyl group, a naphthyl group, etc.) or a furyl group. However, in General formula (19), at least one of R < ₃ > -R < ₆ > is a substituent.

In the formula, R ₉ is selected from the group consisting of a linear or branched alkylene group having 1 to 12 carbon atoms, a linear or branched poly (alkyleneoxy) group, or the following general formulas (22), (23) and (24). Represents a divalent group.

  As an example of the branched alkylene group having 1 to 12 carbon atoms, an alkylene group represented by the following general formula (21) is preferably used.

Wherein, R ₁₀ represents a lower alkyl group (e.g., methyl group, ethyl group, propyl group).

In the formula, n represents 0 or an integer of 1 to 2000, and R ₁₂ represents an alkyl group having 1 to 10 carbon atoms (for example, methyl group, ethyl group, propyl group, butyl group, pentyl group, hexyl group, heptyl group). R ₁₁ represents an alkyl group having 1 to 10 carbon atoms (for example, methyl group, ethyl group, propyl group, butyl group, pentyl group, hexyl group, heptyl group, octyl group, Nonyl group or the like) or a group represented by the following general formula (25).

In the formula, j represents 0 or an integer of 1 to 100, and R ₁₃ represents an alkyl group having 1 to 10 carbon atoms (for example, methyl group, ethyl group, propyl group, butyl group, pentyl group, hexyl group, heptyl group). Octyl group, nonyl group and the like.

In the formula, R ₁₄ is a hydrogen atom, an alkyl group having 1 to 10 carbon atoms (for example, methyl group, ethyl group, propyl group, butyl group, pentyl group, hexyl group, heptyl group, octyl group, nonyl group, etc.), C1-C10 alkoxy group (for example, methoxy group, ethoxy group, propoxy group, butoxy group, pentoxy group, etc.), halogen atom (for example, fluorine atom, chlorine atom, bromine atom, iodine atom, etc.), nitro group , A cyano group, a mercapto group, an alkoxycarbonyl group (for example, a methyloxycarbonyl group, an ethyloxycarbonyl group, a butyloxycarbonyl group, etc.) or a carboxyl group.

In the formula, R ₁₅ represents an oxygen atom, a sulfur atom, —NH—, —SO—, —SO ₂ —, —CH ₂ —, —C (CH ₃ ) ₂ —, or —C (CF ₃ ) ₂ —. To express.

Preferred embodiments of the partial structure of the compound having an oxetane ring used in the present invention include, for example, in the above general formulas (19) and (20), R ₁ is a lower alkyl group (for example, a methyl group, an ethyl group, a propyl group). Group, etc.), preferably an ethyl group. Further, R ₉ is preferably a hexamethylene group or one in which R ₁₄ is a hydrogen atom in the general formula (23).

In the general formula (21), R ₁₀ is an ethyl group, R ₁₂ and R ₁₃ are methyl groups, and Z is a hydrocarbon group containing no oxygen or sulfur atom.

  Furthermore, as an example of the preferable aspect of the compound which has an oxetane ring which concerns on this invention, the compound represented by following General formula (26) is mentioned.

In the formula, r is an integer of 25 to 200, and R ₁₆ represents an alkyl group having 1 to 4 carbon atoms (for example, a methyl group, an ethyl group, a propyl group, a butyl group, etc.) or a trialkylsilyl group. R ₁ , R ₃ , R ₅ and R ₆ have the same meanings as the substituents represented by R _{1 to} R ₆ in the general formula (14). However, at least one of R _{3 to} R ₆ is a substituent.

  Hereinafter, although the specific example of the compound which has an oxetane ring substituted by 2-position which concerns on this invention is shown as exemplary compounds 1-15, this invention is not limited to these.

1: trans-3-tert-butyl-2-phenyloxetane 2: 3,3,4,4-tetramethyl-2,2-diphenyloxetane 3: di [3-ethyl (2-methoxy-3-oxetanyl)] Methyl ether 4: 1,4-bis (2,3,4,4-tetramethyl-3-ethyl-oxetanyl) butane 5: 1,4-bis (3-methyl-3-ethyloxetanyl) butane 6: di ( 3,4,4-trimethyl-3-ethyloxetanyl) methyl ether 7: 3- (2-ethyl-hexyloxymethyl) -2,2,3,4-tetramethyloxetane 8: 2- (2-ethyl-hexyl) Oxy) -2,3,3,4,4-pentamethyl-oxetane 9: 4,4'-bis [(2,4-dimethyl-3-ethyl-3-oxetanyl) methoxy] biphenyl 1 : 1,7-bis (2,3,3,4,4- pentamethyl - oxetanyl) heptane)
11: Oxetanyl silsesquioxane 12: 2-methoxy-3,3-dimethyloxetane 13: 2,2,3,3-tetramethyloxetane 14: 2- (4-methoxyphenyl) -3,3-dimethyloxetane 15: Di (2- (4-methoxyphenyl) -3-methyloxetane-3-yl) ether According to the present invention, the synthesis of a compound having an oxetane ring substituted at least at the 2-position is described in the literature described below. It can be synthesized for reference.

(1) Hu Xianming, Richard M. et al. Kellogg, Synthesis, 533-538, May (1995)
(2) A. O. Fitton, J .; Hill, D.C. Ejane, R.A. Miller, Synth. , 12, 1140 (1987)
(3) Toshiro Imai and Shinya Nishida, Can. J. et al. Chem. Vol. 59, 2503-2509 (1981)
(4) Nobujiro Shimizu, Shintaro Yamaoka, and Yuho Tsuno, Bull. Chem. Soc. Jpn. 56, 3853-3854 (1983)
(5) Walter Fisher and Cyril A.M. Grob, Helv. Chim. Acta. , 61, 2336 (1978)
(6) Chem. Ber. 101, 1850 (1968)
(7) “Heterocyclic Compounds with Three- and Four-membered Rings”, Part Two, Chapter IX, Interscience Publishers, John Wiley & Sons, NewYor (1964).
(8) Bull. Chem. Soc. Jpn. 61, 1653 (1988)
(9) Pure Appl. Chem. , A29 (10), 915 (1992)
(10) Pure Appl. Chem. , A30 (2 &amp; 3), 189 (1993)
(11) Japanese Patent Application Laid-Open No. 6-16804 (12) German Patent No. 1,021,858 In the actinic ray curable ink-jet ink of a compound having an oxetane ring substituted at least 2-position according to the present invention The content is preferably 1 to 97% by mass, more preferably 30 to 95% by mass.

(Combination of oxetane compound and other monomers)
In addition, the compound having an oxetane ring substituted at least at the 2-position according to the present invention may be used alone, or two types having different structures may be used in combination, and a photopolymerizable monomer described later. And photopolymerizable compounds such as polymerizable monomers can be used in combination. When used in combination, the mixing ratio is preferably adjusted so that the compound having an oxetane ring substituted at least at the 2-position is 10 to 98% by mass in the mixture, and other photopolymerizable monomers and polymerizable monomers. It is preferable to adjust the photopolymerizable compound such as 2 to 90% by mass.

(Oxetane compound having a substituent only at the 3-position)
In the present invention, the oxetane compound having a substituent at the 2-position and a conventionally known oxetane compound can be used in combination, and among them, an oxetane compound having a substituent only at the 3-position can be preferably used together.

  Here, as the oxetane compound having a substituent only at the 3-position, for example, known compounds introduced in JP-A Nos. 2001-220526 and 2001-310937 can be used.

  Examples of the compound having a substituent only at the 3-position include a compound represented by the following general formula (27).

In the general formula (27), 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 a methyl group, an ethyl group, a propyl group, butyl alkyl group having 1 to 6 carbon atoms such as, 1-propenyl, 2-propenyl, 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 one oxetane ring because of excellent adhesiveness, low viscosity and excellent workability.

  An example of a compound having two oxetane rings includes a compound represented by the following general formula (28).

In the general formula (28), R ¹ is the same group as that in the general formula (27). 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 can also include a polyvalent group selected from the groups represented by the following general formulas (29), (30) and (31).

In the general formula (29), 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, or a carbon such as a methoxy group, an ethoxy group, a propoxy group or a butoxy group. It is 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 alkoxycarbonyl group, a carboxyl group or a carbamoyl group.

In the general formula (30), 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 (31), 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. The R ^7, may also be mentioned groups selected from the groups represented further by the following general formula (32).

In the general formula (32), 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.

  Specific examples of the compound having two oxetane rings include the following compounds.

Illustrative compound 1 is a compound in which R ¹ is an ethyl group and R ³ is a carboxyl group in the general formula (28). Exemplary compound 2 is a compound in which R ¹ is an ethyl group, R ³ is the general formula (31), R ⁶ and R ⁷ are methyl groups, and n is 1 in the general formula (28).

In the compound having two oxetane rings, a preferred example other than the above compound is a compound represented by the following general formula (33). In the general formula (33), R ¹ has the same meaning as R ¹ in the general formula (27).

  An example of a compound having 3 to 4 oxetane rings is a compound represented by the following general formula (34).

In the general formula (34), R ¹ has the same meaning as R ¹ in the general formula (27). 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. Moreover, in said D, p is an integer of 1-10.

  Illustrative compound 3 is an example of a compound having 3 to 4 oxetane rings.

  Furthermore, examples of the compound having 1 to 4 oxetane rings other than those described above include compounds represented by the following general formula (35).

In the general formula (35), R ⁸ has the same meaning as R ⁸ in the general formula (32). 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.

  Preferred specific examples of the oxetane compound according to the present invention include exemplified compounds 4, 5, and 6 shown below.

  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 following exemplified compounds 7, 8, and 9.

  As the epoxy compound according to the present invention, any of a monomer having an epoxy group and an oligomer thereof can be used. Specific examples include conventionally known aromatic epoxy compounds, alicyclic epoxy compounds, and aliphatic epoxy compounds. Hereinafter, the epoxy compound means a monomer or an oligomer thereof. As the oligomer in the present invention, a low molecular weight compound is preferable, and an oligomer having a molecular weight of less than 1000 is more preferable.

  A preferable aromatic epoxy compound is a di- or polyglycidyl ether produced by the reaction of a polyhydric phenol having at least one aromatic nucleus or an alkylene oxide adduct thereof and epichlorohydrin, for example, bisphenol A or its Examples thereof include di- or polyglycidyl ethers of alkylene oxide adducts, hydrogenated bisphenol A or di- or polyglycidyl ethers of alkylene oxide adducts thereof, and novolak-type epoxy resins. Here, examples of the alkylene oxide include ethylene oxide and propylene oxide.

  As the alicyclic epoxy compound, cyclohexene oxide obtained by epoxidizing a compound having at least one cycloalkane ring such as cyclohexene or cyclopentene ring with a suitable oxidizing agent such as hydrogen peroxide or peracid. Alternatively, a cyclopentene oxide-containing compound is preferable, and specific examples include the compounds shown below.

  Preferred examples of the aliphatic epoxy compound include di- or polyglycidyl ethers of aliphatic polyhydric alcohols or alkylene oxide adducts thereof, and typical examples thereof include diglycidyl ether of ethylene glycol and diglycidyl ether of propylene glycol. Or polyglycidyl ether of polyhydric alcohol such as diglycidyl ether of alkylene glycol such as diglycidyl ether of 1,6-hexanediol, glycerin or alkylene oxide adduct thereof, polyethylene glycol or alkylene oxide thereof Diglycidyl ether, poly (alkylene glycol) such as polypropylene glycol or diglycidyl ether of alkylene oxide adducts thereof Include diglycidyl ether of. Here, examples of the alkylene oxide include ethylene oxide and propylene oxide.

  In addition to these compounds, monoglycidyl ethers of aliphatic higher alcohols and monoglycidyl ethers of phenol and cresol, which are monomers having one oxirane ring in the molecule, can also be used. Among these epoxy compounds, in view of fast curability, aromatic epoxy compounds and alicyclic epoxy compounds are preferable, and alicyclic epoxy compounds are particularly preferable. In the present invention, one of the above epoxy compounds may be used alone, but two or more may be used in appropriate combination.

  The alicyclic epoxy compound represented by the general formula (A), (I) or (II) will be described.

In the general formula (A), (I) or (II), R ₁₀₀ , R ₁₀₁ , R ₁₀₂ represent a substituent. Examples of the substituent include a halogen atom (for example, chlorine atom, bromine atom, fluorine atom). Etc.), an alkyl group having 1 to 6 carbon atoms (for example, methyl group, ethyl group, propyl group, isopropyl group, butyl group, etc.), 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 etc.), acyl group (eg acetyl group, propionyl group, trifluoroacetyl group etc.), acyloxy group (eg acetoxy group, propionyloxy) Group, trifluoroacetoxy group, etc.), alkoxycarbonyl group (for example, methoxycarbonyl group, ethoxycarbonyl group, t-butoxycarbonyl group, etc.) It is below. As the substituent, an alkyl group, an alkoxy group, and an alkoxycarbonyl group are preferable.

  m0, m1, and m2 represent an integer of 0 to 2, and 0 or 1 is preferable. M0, m1, and m2 may be different within the same molecule.

L ₀ represents an r0 + 1 valent linking group or single bond having 1 to 15 carbon atoms which may contain an oxygen atom or a sulfur atom in the main chain, and L ₁ represents 1 to carbon atoms which may contain an oxygen atom or a sulfur atom in the main chain. 15 represents an r1 + 1 valent linking group or a single bond, and 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.

  Examples of the divalent linking group having 1 to 15 carbon atoms which 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, —CO— group. , A group formed by combining a plurality of —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 O—CH (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 O—CH (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 as many hydrogen atoms as necessary from the divalent linking groups listed above, an —O— group, an —S— group, and a —CO— group. , A group formed by combining a plurality of —CS— groups.

L ₀ , L ₁ and L ₂ may each have a substituent. Examples of the substituent include a halogen atom (for example, chlorine atom, bromine atom, fluorine atom, etc.), an alkyl group having 1 to 6 carbon atoms (for example, methyl group, ethyl group, propyl group, isopropyl group, butyl group, etc.) ), 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, etc.), acyl group (for example, acetyl group, Propionyl group, trifluoroacetyl group, etc.), acyloxy group (eg, acetoxy group, propionyloxy group, trifluoroacetoxy group, etc.), alkoxycarbonyl group (methoxycarbonyl group, ethoxycarbonyl group, t-butoxycarbonyl group, etc.), etc. Can be mentioned. As the substituent, an alkyl group, an alkoxy group, and an alkoxycarbonyl group are preferable. L ₀ , L ₁ and L ₂ are each 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 the main chain having 1 to 5 carbon atoms consisting only of carbon. The divalent linking group is more preferable.

  In the present invention, a photopolymerizable compound includes a compound having an oxetane ring and an alicyclic epoxy compound having two or more ester bonds. A compound represented by any one of the general formulas (III) and (IV) is preferable.

In the above formula, R ₂₀₀ and R ₂₀₁ each represents an aliphatic group. Examples of the aliphatic group include an alkyl group having 1 to 6 carbon atoms (for example, methyl group, ethyl group, propyl group, isopropyl group, butyl group, etc.), and a cycloalkyl group having 3 to 6 carbon atoms (for example, cyclopropyl group). Group, cyclobutyl group, cyclopentyl group, cyclohexyl group, etc.), alkenyl group having 1 to 6 carbon atoms (for example, vinyl group, 1-propenyl group, 2-propenyl group, 2-butenyl group, etc.), carbon number 1 To 6 alkynyl groups (for example, acetylenyl group, 1-propynyl group, 2-propynyl group, 2-butynyl group, etc.). Preferably it is a C1-C3 alkyl group, and a methyl group and an ethyl group are more preferable.

  m3 and m4 represent 0 to 2, and preferably 1 or more.

X ₁ represents — (CH ₂ ) _n0 — or — (O) _n0 —, and X ₂ represents — (CH ₂ ) _n1 — or — (O) _n1 —. n0 and n1 represent 0 or 1, and when n0 and n1 are 0, it represents that X ₁ and X ₂ do not exist.

  m3 + n0 or m4 + n1 is preferably 1 or more.

L ₃ may contain a linking group or a single bond having an R3 + 1 valent branched structure having 1 to 15 carbon atoms which may contain an oxygen atom or a sulfur atom in the main chain, and L ₄ may contain an oxygen atom or a sulfur atom in the main chain A linking group or a single bond having an r4 + 1 valent branched structure having 1 to 15 carbon atoms is represented. Examples of the divalent linking group having 1 to 15 carbon atoms which 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, —CO— group. , A group formed by combining a plurality of —CS— groups.

Ethylidene group [> CHCH ₃ ]
Isopropylidene [> C (CH ₃ ) 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-dimethyl-3-oxa-1,5-pentanediyl group [—CH (CH ₃ ) CH ₂ OCH (CH ₃ ) 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 —]
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 as many hydrogen atoms as necessary from the divalent linking groups listed above, an —O— group, an —S— group, and a —CO— group. , A group formed by combining a plurality of —CS— groups.

L ₃ and L ₄ may have a substituent. Examples of the substituent include a halogen atom (eg, chlorine atom, bromine atom, fluorine atom, etc.), an alkyl group having 1 to 6 carbon atoms (eg, methyl group, ethyl group, propyl group, isopropyl group, butyl group). Etc.), 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, etc.), acyl group (for example, Acetyl group, propionyl group, trifluoroacetyl group, etc.), acyloxy group (for example, acetoxy group, propionyloxy group, trifluoroacetoxy group, etc.), alkoxycarbonyl group (for example, methoxycarbonyl group, ethoxycarbonyl group, t- Butoxycarbonyl group, etc.). As the substituent, a halogen atom, an alkyl group, and an alkoxy group are preferable.

  Examples of the general formulas (A), (I), (II), (III), and (IV) are shown below.

  As addition amount of an alicyclic epoxy compound, it is preferable to contain 10-80 mass%. If it is less than 10% by mass, the curability changes remarkably depending on the curing environment (temperature, humidity) and cannot be used. If it exceeds 80% by mass, the film properties after curing are weak and cannot be used. In the present invention, one type of alicyclic 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, Vol. 5, No. 5, Advertisement, Small Ring Heterocycles Part 3, Oxilanes, John & Wiley and Sons, An Inc. 42, 1986, Yoshimura, Adhesion, Vol. 30, No. 7, 42, 1986, Japanese Patent Application Laid-Open No. 11-1000037, Japanese Patent No. 2906245, Japanese Patent No. 2926262, and the like.

  The actinic ray curable composition of the present invention contains an epoxidized fatty acid ester or an epoxidized fatty acid glyceride as an epoxy compound.

  By using epoxidized fatty acid ester or epoxidized fatty acid glyceride in combination with oxetane compound / alicyclic epoxy compound system, it is not only preferable from the viewpoint of safety / environment such as AMES and sensitization, skin irritation, odor, etc. Conventional problems such as generation of wrinkles due to curing shrinkage and poor curability and dischargeability can be solved depending on the curing environment (temperature, humidity).

  The epoxidized fatty acid ester and epoxidized fatty acid glyceride that can be used in the present invention are not particularly limited as long as an epoxy group is introduced into the fatty acid ester or fatty acid glyceride.

  The epoxidized fatty acid ester is produced by epoxidizing an oleic acid ester, and examples thereof include methyl epoxy stearate, butyl epoxy stearate, octyl epoxy stearate and the like. Similarly, epoxidized fatty acid glyceride is produced by epoxidizing soybean oil, linseed oil, castor oil and the like, and epoxidized soybean oil, epoxidized linseed oil, epoxidized castor oil and the like are used.

  The actinic ray curable ink-jet ink of the present invention contains a pigment as a coloring material. The pigments that can be preferably used in the present invention are listed below.

C. I Pigment Yellow-1, 3, 12, 13, 14, 17, 42, 74, 81, 83, 87, 93, 95, 109, 120, 128, 138, 139, 151, 166, 180, 185
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, 101, 122, 144, 146, 177, 185
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. As the dispersion medium, it is preferable in view of dispersion suitability to select a photopolymerizable compound, and among them, a monomer having the lowest viscosity.

  The pigment is preferably dispersed so that the average particle size of the pigment particles is 0.08 to 0.5 μm, and the maximum particle size is 0.3 to 10 μm, preferably 0.3 to 3 μm. Select the dispersion medium, dispersion conditions, and filtration conditions as appropriate. 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 actinic ray curable inkjet ink of the present invention, the colorant concentration is preferably 1% by mass to 10% by mass of the whole ink.

  As the pigment dispersant, one having a basic anchor portion is preferably used, and a polymer dispersant having a comb structure is more preferably used.

  Specific examples of pigment dispersants that can be used in the present invention include Solsperse 9000, 17000, 18000, 19000, 20000, 24000SC, 24000GR, 24000GR, 28000, 32000, Ajinomoto Fine-Techno Co., Ltd. manufactured by Avecia. Examples include Addispar PB821, PB822, PLAAD ED214, ED251, DISPARLON DA-325, DA-234, EFKA-5207, 5244, 6220, 6225, etc. manufactured by EFKA. In addition, pigment derivatives (synergists) that can be used in combination with the pigment dispersant include specific examples of pigment derivatives such as Avecia Solsperse 5000, 12000, 22000, EFKA EFKA-6746, 6750, and the like. Can be mentioned.

  The actinic ray curable composition of the present invention contains a 4- to 10-membered aliphatic cyclic ester compound or a 5- or more-membered cyclic ether compound to improve curability and adhesion to various substrates. preferable.

  The cyclic ester compound is a 4- to 10-membered aliphatic cyclic ester compound. Specifically, ε-caprolactone-6-hydroxyhexanoic acid-1,6 lactone, β-propiolactone, β-butyrolactone, α-methyl-β-butyrolactone, γ-butyrolactone, γ-valerolactone, δ-valero Lactone, ε-caprolactone, γ-caprolactone, γ-heptanolactone, coumarin, tetronic acid, pyrone, phthalide, 3-methyl-1,4-dioxa-2,5-dione, p-dioxanone, morpholinedione, morpholine Etc. In addition, a mixture thereof may be used.

  The cyclic ether compound is a cyclic ether compound having 5 or more members. More preferred is a cyclic ether compound having no carbonate ester structure. Specifically, 1,3-dioxolane, tetrahydrofuran, 1,4-dioxane, 1,3,5-trioxane, crown ether (12-crown-4 etc.), 1,2-dimethyltetrahydrofuran, 2-methyltetrahydrofuran, 2-methyldioxolane, 4-methyldioxolane and the like.

  The content of the 4- to 10-membered aliphatic cyclic ester compound and the 5- or more-membered cyclic ether compound is preferably 1 to 10% by mass.

  In the actinic ray curable composition of the present invention, various additives other than those described above can be used. For example, surfactants, leveling additives, matting agents, polyester resins for adjusting film properties, polyurethane resins, vinyl resins, acrylic resins, rubber resins, and waxes can be added. In addition, for the purpose of improving storage stability, any known basic compound can be used, but representative examples include basic alkali metal compounds, basic alkaline earth metal compounds, amines and other basic organic compounds. Etc. It is also possible to use a radical-cation hybrid type curable ink.

  Basic compounds can also be added. By containing the basic compound, not only the ejection stability becomes good, but also the generation of wrinkles due to curing shrinkage is suppressed even under low humidity. As the basic compound, any known compounds can be used, and representative examples include basic alkali metal compounds, basic alkaline earth metal compounds, and basic organic compounds such as amines.

  Examples of the basic alkali metal compound include alkali metal hydroxides (lithium hydroxide, sodium hydroxide, potassium hydroxide, etc.), alkali metal carbonates (lithium carbonate, sodium carbonate, potassium carbonate, etc.), alkali metals. Alcoholate (sodium methoxide, sodium ethoxide, potassium methoxide, potassium ethoxide, etc.). Examples of the basic alkaline earth metal compound include alkaline earth metal hydroxides (magnesium hydroxide, calcium hydroxide, etc.), alkali metal carbonates (magnesium carbonate, calcium carbonate, etc.), alkali metal Examples include alcoholates (magnesium methoxide, etc.).

  Examples of the basic organic compound include amines and nitrogen-containing heterocyclic compounds such as quinoline and quinolidine. Among these, amines are preferable from the viewpoint of compatibility with the photopolymerizable monomer, for example, octylamine, naphthylamine, Xylenediamine, dibenzylamine, diphenylamine, dibutylamine, dioctylamine, dimethylaniline, quinuclidine, tributylamine, trioctylamine, tetramethylethylenediamine, tetramethyl-1,6-hexamethylenediamine, hexamethylenetetramine and triethanolamine, etc. Is mentioned.

  The concentration when the basic compound is present is preferably in the range of 10 to 1000 ppm by mass, particularly 20 to 500 ppm by mass relative to the total amount of the photopolymerizable monomer. In addition, a basic compound may be used individually or may be used in combination of multiple.

  In the actinic ray curable ink-jet ink of the present invention, the actinic ray curable composition having a viscosity at 25 ° C. of 7 to 40 mPa · s is stable and discharges regardless of the curing environment (temperature and humidity). In order to obtain a good curability.

  As a recording material that can be used in the present invention, in addition to ordinary uncoated paper, coated paper, etc., various non-absorbable plastics and films used for so-called soft packaging can be used. Examples thereof include PET film, OPS film, OPP film, ONy film, 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.

  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.

  Next, the image forming method of the present invention will be described.

  In the image forming method of the present invention, a method is preferred in which the ink 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.

(Total ink film thickness after ink landing)
In the present invention, the total ink film thickness after the ink has landed on the recording material and cured by irradiation with actinic rays is preferably 2 to 25 μm. In the actinic ray curable ink jet recording in the screen printing field, the total ink film thickness currently exceeds 25 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. In addition to the problem of curling and wrinkles, there is a problem in that the entire printed material is changed in its strain and texture.

  Here, “total ink film thickness” means the maximum value of the film thickness of the ink drawn on the recording material, and even for a single color, other two colors are superimposed (secondary color), three colors are superimposed, four colors are used. Even when recording is performed by the overlapping (white ink base) inkjet recording method, the meaning of the total ink film thickness is the same.

(Ink ejection conditions)
As the ink ejection conditions, it is preferable from the viewpoint of ejection stability that the recording head and ink are heated to 35 to 100 ° C. and ejected. Actinic radiation curable inkjet ink has a large range of viscosity variation due to temperature fluctuations, and the viscosity fluctuations directly affect the droplet size and droplet ejection speed, causing image quality degradation. It is necessary to keep. The control range of the ink temperature is set temperature ± 5 ° C., preferably set temperature ± 2 ° C., more preferably set temperature ± 1 ° C. Moreover, in this invention, it is preferable that the amount of droplets discharged from each nozzle is 2 to 15 pl.

(Light irradiation conditions after ink landing)
In the image forming method of the present invention, the active light is preferably irradiated for 0.001 second to 1 second after the ink landing, more preferably 0.001 second to 0.5. Seconds. In order to form a high-definition image, it is particularly important that the irradiation timing is as early as possible.

In the ink jet recording method according to the present invention, after the ink composition is attached to a recording medium, light irradiation is performed. The light irradiation may be visible light irradiation or ultraviolet irradiation, and ultraviolet irradiation is particularly preferable. When performing ultraviolet irradiation, ultraviolet ray irradiation quantity is 100 mJ / cm ² or more, preferably 500 mJ / cm ² or more and 10,000 / cm ² or less, preferably performed at 5,000 mJ / cm ² or less. An ultraviolet irradiation amount within such a range is advantageous because a sufficient curing reaction can be carried out and the colorant can be prevented from fading due to ultraviolet irradiation. Examples of ultraviolet irradiation include lamps such as metal halide lamps, xenon lamps, carbon arc lamps, chemical lamps, low-pressure mercury lamps, and high-pressure mercury lamps. For example, a commercially available product such as an H lamp, a D lamp, or a V lamp manufactured by Fusion System can be used.

  The metal halide lamp has a continuous spectrum as compared with a high-pressure mercury lamp (main wavelength is 365 nm), has high luminous efficiency in the range of 200 to 450 nm, and has a long wavelength range. Therefore, when a pigment is used as in the actinic ray curable composition of the present invention, a metal halide lamp is suitable.

  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 head unit, and the 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. US Pat. No. 6,145,979 discloses a method using an optical fiber as an irradiation method, and a method of irradiating a recording unit with UV light by applying a collimated light source to a mirror surface provided on the side surface of the head unit. ing. Any of these irradiation methods can be used in the image forming method of the present invention.

  Further, a method of irradiating actinic rays in two stages, first irradiating actinic rays by the above-described method within 0.001 to 2 seconds after ink landing, and irradiating actinic rays after completion of all printing is also preferable. This is one aspect. 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.

  Conventionally, in the UV ink jet system, a light source with high illuminance in which the total power consumption of the light source exceeds 1 kW · hr is usually used in order to suppress dot spreading and bleeding after ink landing. However, when these light sources are used, particularly in printing on a shrink label or the like, the shrinkage of the recording material is so large that it cannot be practically used.

  In the present invention, it is preferable to use an actinic ray having the highest illuminance in the wavelength region of 254 nm, and even if a light source having a total power consumption of 1 kW · hr or more is used, a high-definition image can be formed and the recording material can be shrunk. Within practically acceptable level.

  In the present invention, it is preferable that the total power consumption of the light source for irradiating actinic rays is less than 1 kW · hr. Examples of the light source having a total power consumption of less than 1 kW · hr include, but are not limited to, a fluorescent tube, a cold cathode tube, a hot cathode tube, and an LED.

  Next, an ink jet recording apparatus (hereinafter simply referred to as a recording apparatus) of the present invention will be described.

  The recording apparatus of the present invention will be described below with reference to the drawings as appropriate. Note that the recording apparatus of the drawings is merely one aspect of the recording apparatus of the present invention, and the recording apparatus of the present invention is not limited to this drawing.

  FIG. 1 is a front view showing the configuration of the main part of the recording apparatus of the present invention. The recording apparatus 1 includes a head carriage 2, a recording head 3, an irradiation unit 4, a platen unit 5, and the like. In the recording apparatus 1, the platen unit 5 is installed under the recording material P. The platen unit 5 has a function of absorbing ultraviolet rays, and absorbs excess ultraviolet rays that have passed through the recording material P. As a result, a high-definition image can be reproduced very stably.

  The recording material P is guided by the guide member 6 and moves from the near side to the far side in FIG. 1 by the operation of the conveying means (not shown). A head scanning unit (not shown) scans the recording head 3 held by the head carriage 2 by reciprocating the head carriage 2 in the Y direction in FIG.

  The head carriage 2 is installed on the upper side of the recording material P, and stores a plurality of recording heads 3 to be described later according to the number of colors used for image printing on the recording material P, with the discharge ports arranged on the lower side. The head carriage 2 is installed with respect to the main body of the recording apparatus 1 in such a manner that it can reciprocate in the Y direction in FIG. 1, and reciprocates in the Y direction in FIG. 1 by driving the head scanning means.

  In FIG. 1, the head carriage 2 is illustrated as accommodating the recording heads 3 of yellow (Y), magenta (M), cyan (C), and black (K). The number of colors of the recording head 3 housed in the head carriage 2 can be determined as appropriate.

  The recording head 3 is operated by a discharge means (not shown) provided with a plurality of actinic ray curable inkjet inks (for example, UV curable ink) supplied by an ink supply means (not shown). The ink is discharged from the discharge port toward the recording material P. The UV ink ejected by the recording head 3 is composed of a coloring material, a polymerizable monomer, an initiator, and the like, and the monomer crosslinks when the initiator acts as a catalyst when irradiated with ultraviolet rays. It has the property of being cured by a polymerization reaction.

  During the scanning in which the recording head 3 moves from one end of the recording material P to the other end of the recording material P in the Y direction in FIG. 1 by driving the head scanning means, a certain area (landing possible area) in the recording material P On the other hand, UV ink is ejected as ink droplets, and ink droplets are landed on the landable area.

  The above scanning is performed as many times as necessary, and after UV ink is ejected toward one landable area, the recording material P is appropriately moved from the front to the back in FIG. 1, the recording head 3 discharges UV ink to the next landable area adjacent in the depth direction in FIG.

  An image is formed on the recording material P by repeating the above operation and ejecting the UV ink from the recording head 3 in conjunction with the head scanning means and the conveying means.

  The irradiation unit 4 includes an ultraviolet lamp that emits ultraviolet light in a specific wavelength region with stable exposure energy and a filter that transmits ultraviolet light of a specific wavelength. Here, as the ultraviolet lamp, a mercury lamp, a metal halide lamp, an excimer laser, an ultraviolet laser, a cold cathode tube, a hot cathode tube, a black light, an LED (Light Emitting Diode) and the like can be applied. A cathode tube, a hot cathode tube, a mercury lamp or black light is preferred. In particular, a low-pressure mercury lamp, a hot cathode tube, a cold cathode tube, and a germicidal lamp that emit ultraviolet light having a wavelength of 254 nm are preferable because they can effectively prevent bleeding and control the dot diameter. By using black light as the radiation source of the irradiation means 4, the irradiation means 4 for curing the UV ink can be produced at low cost.

  The irradiating means 4 has substantially the same shape as the maximum one that can be set by the recording apparatus (UV inkjet printer) 1 among the landable areas in which the recording head 3 ejects UV ink by one scan driven by the head scanning means. , Having a shape larger than the landable area.

  The irradiation means 4 is fixed on both sides of the head carriage 2 so as to be substantially parallel to the recording material P.

  As described above, as a means for adjusting the illuminance of the ink discharge portion, not only the entire recording head 3 is shielded, but in addition, the ink discharge of the recording head 3 is determined from the distance h1 between the irradiation means 4 and the recording material P. It is effective to increase the distance h2 between the portion 31 and the recording material P (h1 <h2), or to increase the distance d between the recording head 3 and the irradiation means 4 (d is increased). Further, it is more preferable that a bellows structure 7 is provided between the recording head 3 and the irradiation means 4.

  Here, the wavelength of the ultraviolet rays irradiated by the irradiation means 4 can be changed as appropriate by replacing the ultraviolet lamp or filter provided in the irradiation means 4.

  The actinic ray curable inkjet ink of the present invention can also form an image using a line head type recording apparatus.

  FIG. 2 is a top view illustrating another example of the configuration of the main part of the ink jet recording apparatus. The ink jet recording apparatus shown in FIG. 2 is called a line head system, and a plurality of ink jet recording heads 3 of each color are fixedly arranged on the head carriage 2 so as to cover the entire width of the recording material P. Yes.

  On the other hand, on the downstream side of the head carriage 2, there is provided irradiation means 4 arranged so as to cover the entire width of the recording material P and cover the entire area of the ink printing surface. As the ultraviolet lamp used in the illuminating means 4, the same one as described in FIG. 1 can be used.

  In this line head system, the head carriage 2 and the irradiating means 4 are fixed, and only the recording material P is conveyed, and ink ejection and curing are performed to form an image. In the present invention, the recording material P is desirably heated to 35 to 60 ° C.

  Examples of the present invention will be specifically described below, but the embodiments of the present invention are not limited to these examples.

Example 1
A photopolymerizable compound, a photopolymerization initiator, the compound of the present invention, and other additives were added and dissolved as shown in Tables 1 and 2 to prepare curable compositions. The addition amount in the table indicates mass%.

  The compounds used in the table are as follows.

Celoxide 2021P: Daicel Chemical Industries, Ltd. Vf7010: Vikoflex 7010 (manufactured by ATOFINA)
OXT-221: Toagosei Co., Ltd. OXT-101: Toagosei Co., Ltd. UVI6992: Dow Chemical Co., Ltd. Propion Carbonate 50% solution Irgacure 184: Ciba Specialty Chemicals Co., Ltd. Snowtex 40: Nissan Chemical Co., Ltd. silica sol ( Silica sol solid content obtained by evaporating water having a silica sol solid content of 40% by mass, an aqueous dispersion, and an average particle size of 10 to 20 nm Snowtex S: manufactured by Nissan Chemical Co., Ltd., colloidal silica SiO ₂ content of 30% by mass
Snowtex C: Nissan Chemical Co., colloidal silica, average particle size 0.015μm
IPA-ST: NISSAN CHEMICAL, SiO ₂ content 30% by mass, iso-propyl alcohol-dispersed colloidal silica Ludox AM: DuPont—concentration 20% by mass, alumina modified colloidal silica Viscosity measurement 25 ° C., shear rate The viscosity at 10001 / s was measured.

Evaluation of Curing Sensitivity After applying the obtained curable composition to synthetic paper (synthetic paper YUPO FGS manufactured by YUPO Corporation) so that the film thickness becomes 3 μm, ultraviolet light is changed by changing the amount of ultraviolet light. Irradiation, and after irradiation, the coated cured film was rubbed with a nail to determine whether the film was cured or not. Table 3 shows the minimum irradiation energy (mJ / cm ² ) at which the film cannot be peeled off as the curing sensitivity.

Evaluation of Flexibility After applying the curable composition to synthetic paper (synthetic paper YUPO FGS manufactured by YUPO Corporation) to a film thickness of 80 μm, a hot cathode tube (special order manufactured by NIPPO) 200 W power supply Then, a light amount of 180 mW / cm ² was irradiated 0.1 seconds after landing to obtain a cured product. The obtained cured film was evaluated in accordance with the method for evaluating flex resistance of JIS K 5600.

Evaluation of wrinkles The surface of the curable composition coated or printed and cured so that the cured film thickness was 16 μm was visually evaluated.
5: No generation of wrinkles 4: Slight generation of wrinkles, but no problem in use Level 3: Occurrence of wrinkles, but lower limit of use level 2: Generation of wrinkles, Level 1 causing problems in use : Level at which wrinkles occur and cannot be used.
The results are shown in Table 3.

  From Table 3, it can be seen that the sample of the present invention is strong and flexible with no decrease in sensitivity, and the generation of wrinkles upon thick film curing is improved.

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 4 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 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 dispersed for 2 hours in a paint shaker. Next, the zirconia beads were removed, and various additives such as each photopolymerization initiator, acid proliferating agent, basic compound, and surfactant were added in the combinations shown in Table 4, and this was added to prevent the printer from clogging. An ink composition set was prepared by filtration through an 8 μm membrane filter. The ink viscosity was adjusted to 20 mPaS to 30 mPaS by adjusting the addition amount of the compound having an oxetane ring and the epoxy compound. In Table 4, the addition amount is mass%.

  The compounds used in the table are as follows.

OXT-212: Toagosei Co., Ltd. KF351: Silicone oil (manufactured by Shin-Etsu Chemical Co., Ltd.)
Sumizer MDP-S: manufactured by Sumitomo Chemical Co., Ltd., 2,2′-methylenebis (4-methyl-6-t-butylphenol)
Pigment of each color K: CI pigment black 7
C: CI pigment Blue 15: 3
M: CI pigment Red 57: 1
Y: CI pigment Yellow13
Lk: CI pigment black 7
LC: CI pigment Blue 15: 3
Lm: CI pigment Red 57: 1
Ly: CI pigment Yellow13
* Light color pigment concentration is 1/5
<< Inkjet image forming method >>
Each of the prepared curable composition inks is loaded into an ink jet recording apparatus having the configuration shown in FIG. 1 having a piezo ink jet nozzle, and each of the recording materials having a width of 600 mm and a length of 20 m is subjected to 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 1 inch, that is, the number of dots per 2.54 cm). And the curable composition ink described above was continuously discharged. The recording material was heated to 40 ° C. by a surface heater. After landing, a hot cathode tube on both sides of the carriage (NIPPO's custom-made product) was irradiated with a light amount of 180 mW / cm ² using a 200 W power source and cured instantaneously (less than 0.5 seconds after landing). When the total ink film thickness was measured after image recording, it was in the range of 2 to 60 μm. The inkjet image was formed by printing in an environment of 30 ° C. and 80% 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. The injection properties were all good.

  The details of the abbreviations of each recording material described are as follows.

Synthetic paper: Synthetic paper manufactured by YUPO Corporation YUPO FGS
PVC: polyvinyl chioride
Evaluation method [Evaluation of bleeding]
Printing was performed so that one dot of each color of Y, M, C, K was adjacent to each other at 720 dpi, each adjacent color dot was enlarged with a loupe, the degree of bleeding was visually observed, and color mixing was evaluated according to the following criteria. .

◎: 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 that cannot be used because the adjacent dots are blurred and mixed.

[Evaluation of cocoons]
The same operation as in Example 1 was performed.

[Evaluation of flexibility]
The cured composition is printed on synthetic paper (synthetic paper YUPO FGS manufactured by YUPO Corporation) to a film thickness of 40 μm, and a hot cathode tube (NIPPO custom-made product) using a 200 W power supply, 180 mW / cm Irradiation with a light quantity of ² was performed 0.1 seconds after landing to obtain a cured product. In accordance with the method for evaluating bending resistance of JIS K 5600, the resulting cured film was evaluated for cracking when it was wound around a 5 mmφ rod.
5: No occurrence of cracks 4: Slight occurrence, but no problem in use 3: There is occurrence of cracks, lower limit of use level 2: Frequent cracks, difficult to use Level 1: Frequent cracks, unusable level.
The results are shown in Table 5.

  From the results shown in Table 5, the sample of the present invention was highly sensitive and had no deterioration in ejection properties and image quality. It can be seen that the sample of the present invention is strong and flexible without a decrease in sensitivity, and has improved wrinkle generation upon thick film curing.

It is a front view which shows an example of a structure of the principal part of the inkjet recording device of this invention. It is a top view which shows another example of a structure of the principal part of the inkjet recording device of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Inkjet recording device 2 Head carriage 3 Inkjet recording head 31 Ink ejection port 4 Irradiation means 5 Platen part 6 Guide member 7 Bellows structure P Recording material

Claims (17)

An actinic ray curable composition containing a radical polymerizable monomer as a photopolymerizable compound and an inorganic oxide colloid. An actinic ray curable composition comprising a compound having an oxetane ring and an epoxy compound as a photopolymerizable compound, and a photoacid generator and an inorganic oxide colloid. The actinic ray curable composition according to claim 1 or 2, wherein the inorganic oxide colloid is colloidal silica or alumina colloid. The actinic ray curable composition according to any one of claims 1 to 3, which does not contain 5% or more of water. The photoacid generator is at least one of sulfonium salts represented by the following general formulas (1) to (4) that do not generate benzene by actinic ray irradiation. Item 4. The actinic ray curable composition according to item.

[Wherein R _{S1 to} R _S17 each represents a hydrogen atom or a substituent, R _{S1 to} R _S3 do not simultaneously represent a hydrogen atom, and R _{S4 to} R _S7 do not represent a hydrogen atom at the same time, R _{S8 to} R _S11 do not represent hydrogen atoms at the same time, and R _{S12 to} R _S17 do not represent hydrogen atoms at the same time. X represents a non-nucleophilic anionic residue. ] 6. The actinic ray according to claim 5, wherein the sulfonium salt represented by the general formulas (1) to (4) is at least one of sulfonium salts selected from the following general formulas (5) to (13). A curable composition.

[Wherein, X represents a non-nucleophilic anion residue having the same meaning as in the general formulas (1) to (4). ] The actinic ray curable composition according to any one of claims 2 to 6, wherein the compound having an oxetane ring is a disubstituted oxetane compound. The actinic ray curable composition according to any one of claims 2 to 6, wherein the epoxy compound is an epoxidized fatty acid ester or an epoxidized fatty acid glyceride. The actinic ray curable composition according to any one of claims 2 to 6, wherein the epoxy compound is an alicyclic epoxy compound. An actinic ray curable composition, wherein the alicyclic epoxy compound is a compound represented by the following general formula (A).

Wherein, R ₁₀₀ represents a substituent, m0 represents 0-2. r0 represents 1-3. L ₀ represents a C 1-15 r 0 + 1 valent linking group or single bond that may contain an oxygen atom or a sulfur atom in the main chain. ] The alicyclic epoxy compound represented by the general formula (A) is selected from at least one of the alicyclic epoxy compounds represented by the following general formula (I), (II), (III) or (IV) An actinic ray curable composition, which is characterized by

[Wherein R ₁₀₁ represents a substituent, and m1 represents 0 to 2. 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. ]

[Wherein, R ₁₀₂ represents a substituent, and m2 represents 0 to 2. r2 represents 1-3. L ₂ represents a C 1-15 r 2 + 1 valent linking group or single bond which may contain an oxygen atom or a sulfur atom in the main chain. ]

[Wherein, R ₂₀₀ represents an aliphatic group other than the α and β positions of the oxirane ring, and m3 represents 0 to 2. X ₁ represents — (CH ₂ ) _n0 — or — (O) _n0 —, and n0 represents 0 or 1. p1 and q1 each represents 0 or 1, and are not 0 at the same time. r3 represents 1-3. L ₃ represents a linking group or a single bond having an R ₃ + 1 valent branched structure having 1 to 15 carbon atoms, which may contain an oxygen atom or a sulfur atom in the main chain. ]

[Wherein, R ₂₀₁ represents an aliphatic group other than the α and β positions of the oxirane ring, and m4 represents 0 to 2. X ₂ represents — (CH ₂ ) _n1 — or — (O) _n1 —, and n1 represents 0 or 1. p2 and q2 each represent 0 or 1, and are not 0 at the same time. r4 represents 1-3. L ₄ represents a linking group or a single bond having an r4 + 1-valent branched structure having 1 to 15 carbon atoms, which may contain an oxygen atom or a sulfur atom in the main chain. ] The actinic ray curable composition according to any one of claims 1 to 11, wherein the viscosity at 25 ° C is 7 to 40 mPa · s. The actinic ray curable inkjet ink according to claim 1, wherein the actinic ray curable composition according to claim 1 contains a pigment. 14. An image forming method in which the actinic radiation curable inkjet ink according to claim 13 is jetted onto a recording material from an inkjet recording head, and printing is performed on the recording material, after the actinic radiation curable inkjet ink has landed. Irradiating actinic rays for 0.001 to 1.0 seconds. An image forming method in which the actinic ray curable ink-jet ink according to claim 13 is jetted onto a recording material from an ink-jet recording head, and printing is performed on the recording material, the minimum being ejected from each nozzle of the ink-jet recording head An image forming method, wherein the ink droplet amount is 2 to 15 pl. The inkjet recording apparatus used for the image forming method according to claim 14 or 15, wherein the inkjet recording apparatus includes an actinic ray curable inkjet ink and an inkjet recording head that are heated to 35 ° C to 100 ° C and then discharged. apparatus. The inkjet recording apparatus used for the image forming method of Claim 14 or 15 has a mechanism which discharges actinic-light curable inkjet ink to the recording medium heated at 35-60 degreeC.

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