TWI506098B - Photo-curable ink composition for ink jet - Google Patents

Description

Photocurable ink composition for inkjet

The present invention relates to an inkjet photocuring suitable for use in the production of a display element such as a liquid crystal display element or an electroluminescence (EL) display element, or an electronic circuit board such as a printed wiring board or a flexible wiring board. Sexual ink composition. More specifically, the present invention relates to an inkjet photocurable ink composition suitable for a cover film or the like which protects a surface of a metal wiring forming a predetermined circuit pattern.

When an electronic circuit board such as a printed wiring board, a flexible wiring board, or a semiconductor package substrate is manufactured, a polymer-based cover film is used as a protective film for protecting a conductor surface such as a metal wiring forming a predetermined circuit pattern. The coating film is generally required to have plating resistance, heat resistance, adhesion to a substrate, and flame retardancy.

The method of adhering the cover film to the conductor surface is generally as follows: a surface of the cover film is processed into a predetermined shape, an adhesive is applied to the processed surface, and the film is overlaid on the electronic circuit substrate and aligned. After that, it is heat-pressed by pressing or the like.

In the above method, workability or positional accuracy is a problem in processing the cover film, applying an adhesive to the processed surface, and then performing alignment.

Therefore, in order to improve the above-mentioned problems, a method of forming a protective layer by applying a photosensitive coating agent to a conductor surface has been proposed (for example, refer to Japanese Laid-Open Patent Publication No. SHO45-115541 (Patent Document 1), Japanese Patent Laid-Open No. 51-40922 (Patent Document 2), and Japanese Patent Laid-Open No. 2004-156012 (Patent Document 3)).

Further, after the protective layer is formed, a protective film which constitutes a predetermined fine pattern is formed by performing etching treatment and development using a photoresist.

However, in order to form a protective film using such a photosensitive cover film, patterning of a film exposed by a pattern, etching of the film as described above, and development of a photoresist are required, and many steps are required. Further, the production of the photomask required for the above pattern exposure takes a long time and a lot of cost.

In order to solve such problems, a method of forming a pattern by directly applying a photosensitive material to a substrate by using an inkjet method has been developed (for example, refer to JP-A-2008-239926 (Patent Document 4), Japanese Patent Laid-Open Japanese Patent Publication No. 2009-13269 (Patent Document 6), Japanese Patent Laid-Open Publication No. 2009-13286 (Patent Document 7), Japanese Patent Laid-Open Publication No. 2009-102498 (Patent Document 8), JP-A-2009-102499 (Patent Document 9), JP-A-2007-106892 (Patent Document 10), and JP-A-2007-106893 (Patent Document 11) ). In this method, since the pattern exposure, etching treatment, and development which were previously necessary are not required, the above method is expected as a method having an advantage that the amount of equipment investment is small and the loss of material is small.

However, the photosensitive material for inkjet described in the above-mentioned Patent Documents 4 to 9 is premised on the use of a thermal method (also referred to as "Bubble Jet (registered trademark)), and therefore, a photosensitive component is required. Since it is soluble in water, the raw materials used for the above-mentioned photosensitive materials are limited, and material design becomes difficult. Further, since the temperature of the ink is locally raised by the heater during the ejection, there is a fear that the ink may be deteriorated, or the photosensitive material is aqueous, so that the coating film obtained from the photosensitive material is plated. The aqueous solution is unstable, that is, the plating resistance is insufficient.

In addition, the photosensitive material for inkjet described in the above-mentioned Patent Document 10 and Patent Document 11 is piezoelectrically sprayed, but in order to ensure the ejection property (reducing the viscosity of the photosensitive material), the organic solvent is added to the photosensitive material. The organic solvent has a risk of invading the member of the inkjet apparatus or the electronic circuit board manufacturing apparatus used for the necessary conditions. Further, in order to reduce the environmental load, inkjet inks which are used as much as possible without adding a solvent are desired.

As described above, there is no need to obtain water or an organic solvent, and it is possible to apply an inkjet method, and it is possible to form a coating film having excellent plating resistance, heat resistance, and adhesion to a substrate and flame retardancy. A hardening composition.

[Previous Technical Literature]

[Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open No. 45-115541

[Patent Document 2] Japanese Patent Laid-Open No. 51-40922

[Patent Document 3] Japanese Patent Laid-Open Publication No. 2004-156012

[Patent Document 4] Japanese Patent Laid-Open Publication No. 2008-239926

[Patent Document 5] Japanese Patent Laid-Open Publication No. 2008-239927

[Patent Document 6] Japanese Patent Laid-Open Publication No. 2009-13269

[Patent Document 7] Japanese Patent Laid-Open Publication No. 2009-13286

[Patent Document 8] Japanese Patent Laid-Open Publication No. 2009-102498

[Patent Document 9] Japanese Patent Laid-Open Publication No. 2009-102499

[Patent Document 10] Japanese Patent Laid-Open Publication No. 2007-106892

[Patent Document 11] Japanese Patent Laid-Open Publication No. 2007-106893

In view of the above circumstances, an object of the present invention is to provide a photocurable ink composition for inkjet which has high plating resistance, heat resistance, adhesion to a substrate, and resistance at a high level. The flammability can form a cured film which is particularly excellent in adhesion, and is excellent in sprayability and photocurability.

Further, an object of the present invention is to provide a photocurable ink for inkjet which does not require the addition of water or an organic solvent, has a simple material design, and has a small environmental load.

The present inventors have found that a photocurable ink composition for inkjet containing a specific compound and having a viscosity within a fixed range can solve the above problems, and the present invention has been completed based on the findings.

Further, in addition to the above-described photocurable ink composition for inkjet, the present invention provides an electronic circuit board or the like having a cured film obtained from the composition.

That is, the gist of the present invention is as follows.

[1] A photocurable ink composition for inkjet, comprising:

Compound (A) represented by the following formula (1):

(in the formula (1), R is a divalent organic group having 1 to 100 carbon atoms); and has a group selected from the group consisting of an oxiranyl group, an oxetanyl group, an alkoxyalkyl group, and a hydroxyl group. The compound (B) having at least one functional group; wherein the photocurable ink composition for inkjet has a viscosity at 25 ° C of 200 mPa‧s or less.

[2] The photocurable ink composition for inkjet according to [1], wherein, in the above formula (1), R is a divalent organic group having 1 to 50 carbon atoms.

[3] The photocurable ink composition for inkjet according to [1] or [2] wherein, in the above formula (1), R is an arbitrary discontinuous -CH ₂ - may be an ether bond or an ester bond And a decyl bond, a urethane bond or a carbonyl group substituted with an alkyl group having 1 to 50 carbon atoms, a cycloalkyl group having 3 to 50 carbon atoms or an extended aryl group having 6 to 50 carbon atoms.

[4] The photocurable ink composition for inkjet according to [3], wherein, in the above formula (1), R is an alkylene group having 1 to 50 carbon atoms.

[5] The photocurable ink composition for inkjet according to any one of [1] to [4] wherein the compound (B) has an oxiranyl group and/or an oxetanyl group.

[6] The photocurable ink composition for inkjet according to [5], wherein the compound (B) has an oxirane group.

[7] The photocurable ink composition for inkjet according to [6] wherein the compound (B) is an epoxy compound, and the epoxy compound is selected from the group consisting of a phenol novolak type, a cresol novolac type, and a bisphenol A type. , bisphenol F type, hydrogenated bisphenol A type, hydrogenated bisphenol F type, bisphenol S type, bisphenol A phenol type, trisphenol methane type, tetraphenol ethane type, bisphenol type, biphenol type, At least one of a group consisting of an alicyclic, heterocyclic, dicyclopentadiene or naphthalene type structure.

[8] The photocurable ink composition for inkjet according to any one of [1], wherein the compound (C) other than the compound (B) is further contained, and the compound (C) is selected from the group consisting of At least one polymerizable group of the group consisting of (meth)acryloyl group, allyl group and vinyl group.

[9] The photocurable ink composition for inkjet according to [8], wherein the compound (C) has a (meth) acrylonitrile group.

[10] The photocurable ink composition for inkjet according to any one of [1] to [9], further comprising a photopolymerization initiator (D).

[11] The photocurable ink composition for inkjet according to any one of [1] to [10] further comprising a flame retardant (E).

[12] The photocurable ink composition for inkjet according to any one of [1], wherein the compound (F) other than the compound (A) is further contained, and the compound (F) is selected from the ring. At least one of the group consisting of an oxygen hardener, a melamine resin, and a phenol resin.

[13] An electronic circuit board comprising: a circuit formed on a surface of the substrate; and a cured film formed on at least a part of the substrate and the circuit, wherein the cured film is one of [1] to [12] The inkjet photocurable ink composition described in the section is obtained by curing.

[Effects of the Invention]

The photocurable ink composition for inkjet according to the present invention is excellent in ejectability and photocurability, and can form a cured film which is excellent in plating resistance, heat resistance, adhesion to a substrate, and flame retardancy.

[1. Photocurable ink composition for inkjet according to the present invention]

The photocurable ink composition for inkjet according to the present invention (hereinafter also referred to simply as "the ink composition of the present invention") contains the compound (A) represented by the above formula (1) as described above (hereinafter also referred to as only And "compound (A)") and a compound (B) having at least one functional group selected from the group consisting of an oxiranyl group, an oxetanyl group, an alkoxyalkyl group, and a hydroxyl group (hereinafter) Also known as "compound (B)").

In addition, the ink composition of the present invention may contain a compound having at least one polymerizable group selected from the group consisting of a (meth) acrylonitrile group, an allyl group, and a vinyl group, other than the compound (B), which will be described later. (C), a photopolymerization initiator (D), a flame retardant (E), and a compound (F) may further contain a coloring agent, a solvent, a surfactant, a polymerization inhibitor, etc., if necessary. Further, the ink composition of the present invention may be colorless or colored.

<1.1 Compound (A) represented by the formula (1)>

The compound (A) is represented by the following formula (1), which itself is photopolymerized by a carbon-carbon double bond moiety, and the structural unit derived from the compound (A) is formed into a chain-shaped cured product, and The compound (B) described later is reacted to form a rigid structure, and a cured product excellent in heat resistance and plating resistance is formed.

In the above formula, R is a divalent organic group having 1 to 100 carbon atoms. From the viewpoint of forming a cured product excellent in heat resistance and plating resistance, R is preferably a divalent organic group having 1 to 50 carbon atoms.

Examples of the above-mentioned divalent organic group having 1 to 50 carbon atoms include any discontinuous -CH ₂ - carbon number which may be substituted by an ether bond, an ester bond, a guanamine bond, a urethane bond or a carbonyl group. ～50 alkylene, or a cycloalkylene group having 3 to 50 carbon atoms and an extended aryl group having 6 to 50 carbon atoms.

Specific examples of the above R include a methylene group, an exoethyl group, a propyl group, a butyl group, an ethyloxymethylene group, and a phenyl group. Preferred examples are a methylene group, an exoethyl group and a propylene group. The base is an alkyl group.

From the viewpoint of balance between heat resistance, plating resistance, and adhesion properties of the cured product obtained from the ink composition of the present invention, R is more preferably an alkylene group having 1 to 50 carbon atoms.

The compound (A) represented by the above formula (1) may be used singly or in combination of two or more kinds in the ink composition of the present invention.

If the content of the above compound (A) in the ink composition of the present invention is 15% by weight (% by weight) to 50% by weight based on the total amount of the ink composition, the cured film obtained from the ink composition exhibits It is preferred because of its high plating resistance and heat resistance. The above content is more preferably 15% by weight to 45% by weight, and particularly preferably 15% by weight to 40% by weight, in terms of the balance between the plating resistance and the heat resistance and the sprayability of the ink composition.

Further, the compound (A) can be obtained by reacting the compound (a1) represented by the following formula with methyl maleic anhydride.

In the above formula, R has the same meaning as R in the formula (1). The compound (A) is obtained by reacting the compound (a1) with methyl maleic anhydride to form a quinone imine. Known conditions can be employed in the reaction as the reaction conditions in the quinone imine formation reaction.

The compound (A) used in the present invention has a methyl maleimide structure formed in the above manner, and constitutes an ink composition of the present invention as compared with a compound having a maleimide structure. The solubility in other components is excellent. The compound having a maleimide structure is mostly insoluble to the above other components and is not used in the ink composition of the present invention.

<1.2. A compound (B) having at least one functional group selected from the group consisting of an oxiranyl group, an oxetanyl group, an alkoxyalkyl group, and a hydroxyl group.

The photocurable ink composition for inkjet according to the present invention contains the above compound (B).

The compound (B) is not particularly limited as long as it has at least one functional group selected from the group consisting of an oxiranyl group, an oxetanyl group, an alkoxyalkyl group, and a hydroxyl group.

In the ink composition of the present invention, the functional group of the compound (B) reacts with the carboxyl group of the compound (A) to form a cured product.

When the compound (B) has two or more of the above functional groups, the ink composition of the present invention is excellent in curability. In addition, as described above, the compound (A) is linked to form a chain by photopolymerization, and when the number of the functional groups in the compound (B) is two or more, the free carboxyl group derived from the compound (A) formed of a plurality of chains is expected. Reacts with a functional group in the above compound (B), and a plurality of chains are linked (crosslinked) by the compound (B) to form a plate structure having better firmness, heat resistance, and adhesion to a substrate. A cured film excellent in properties is preferred. Further, the number of the above functional groups in the compound (B) is usually 6 or less.

The compound (B) preferably has an oxirane group and/or an oxetanyl group, and more preferably has a plating resistability, heat resistance and adhesion to the substrate. Ethylene oxide based.

Specific examples of the compound (B) having an oxirane group include a phenol novolak type, a cresol novolac type, a bisphenol A type, a bisphenol F type, a hydrogenated bisphenol A type, and a hydrogenated bisphenol F type. Bisphenol S type, bisphenol A phenol type, trisphenol methane type, tetraphenol ethane type, bisphenol type, biphenol type, alicyclic type, heterocyclic type, dicyclopentadiene type, or naphthalene type The structure constitutes an epoxy compound of at least one structure in the group.

Among the above-mentioned compounds, from the viewpoints of plating resistance, heat resistance and adhesion to a substrate of the cured film obtained from the ink composition of the present invention, a phenol novolak type, a cresol novolak type, and a bisphenol are preferable. A type and bisphenol F type epoxy compound, among which bisphenol A type and bisphenol F type epoxy compound are especially preferable.

Commercial products of the epoxy compound exemplified above include Epikote 828, Epikote 834, Epikote 1001, Epikote 1004 (trade name, manufactured by Mitsubishi Chemical Corporation), Epicor 840, Epicron 850, Epicron 1050, and Epicron 2055 (products). Name, Di Ai Sheng (DIC) (manufactured), Epotohto YD-011, Epotohto YD-013, Epotohto YD-127, Epotohto YD-128 (trade name, manufactured by Dongdu Chemical Co., Ltd.), DER317, DER331, DER661, DER664 (trade name, manufactured by Dow Chemical Japan), Araldite 6071, Araldite 6084, Araldite GY250, Araldite GY260 (trade name, manufactured by BASF Japan) , Sumi-Epoxy ESA-011, Sumi-Epoxy ESA-014, Sumi-Epoxy ELA-115, Sumi-Epoxy ELA-128 (trade name, manufactured by Sumitomo Chemical Industries Co., Ltd.), and AER330, AER331, AER661 , AER664 (trade name, manufactured by Asahi Kasei E-Materials), bisphenol A type epoxy compound; Epikote 152, Epikote 154 (trade name, manufactured by Mitsubishi Chemical Corporation), Dow Epoxy DEN-431, Dow Epoxy DEN-438, Dow Epoxy DEN-439, Dow Epoxy D EN-485 (trade name, manufactured by Dow Chemical Japan), Araldite EPN-1138, Araldite EPN-1139 (trade name, manufactured by BASF Japan), Epicron N-730, Epicron N-738, Epicron N- Phenolic novolac type epoxy compound such as 740 (trade name, manufactured by DIC); Epicron N-660, Epicron N-665, Epicron N-670, Epicron N-673, Epicron N-695 (trade name, DIC) )) cresol novolac type epoxy compound such as EOCN-1020, EOCN-102S, EOCN-104S (trade name, manufactured by Nippon Chemical Co., Ltd.); Epicron 830 (trade name, manufactured by DIC), JER807 (trade name, manufactured by Mitsubishi Chemical Co., Ltd.), Epotohto YDF-170 (trade name, manufactured by Tohto Kasei Co., Ltd.), and YDF-175, YDF-2001, YDF-2004, Araldite XPY306 (trade name, BASF Japan ( Bisphenol F-type epoxy compound; Epotohto ST-2004, Epotohto ST-2007, Epotohto ST-3000 (trade name, manufactured by Tosho Kasei Co., Ltd.), etc. Hydrogenated bisphenol A epoxy compound; Celloxide 2021 (trade name, manufactured by Daicel Chemical Industry Co., Ltd.), and alicyclic epoxidation such as Araldite CY175 and Araldite CY179 (trade name, manufactured by BASF Japan) YL-933 (trade name, manufactured by Mitsubishi Chemical Corporation), EPPN-501, EPPN-502 (trade name, manufactured by Dow Chemical Japan), Tecmoa VG3101L (manufactured by Mitsui Chemicals Co., Ltd.) Methane type epoxy compound; YL-6056, YX-4000, YL-6121 (trade name, manufactured by Mitsubishi Chemical Corporation), etc., such as bisphenol type or biphenol type epoxy compound or a mixture thereof; EBPS-200 ( Trade name, manufactured by Nippon Kayaku Co., Ltd., bisphenol S-type epoxy compound such as EPX-30 (trade name, manufactured by ADEKA) and EXA-1514 (trade name, manufactured by DIC); JER157S ( Trade name, manufactured by Mitsubishi Chemical Co., Ltd.), bisphenol A phenolic epoxy compound; YL-931 (trade name, manufactured by Mitsubishi Chemical Corporation) and Araldite 163 (trade name, manufactured by BASF Japan) Phenolethane type epoxy compound; Araldite PT810 (trade name, manufactured by BASF Japan) and TEPIC (trade name, manufactured by Nissan Chemical Industries Co., Ltd.); heterocyclic epoxy compounds; HP-4032, EXA-4750 , a naphthalene type epoxy compound such as EXA-4700 (trade name, manufactured by DIC); a dicyclopentadiene type ring such as HP-7200, HP-7200H, HP-7200HH (trade name, manufactured by DIC) Compound.

Further, examples of the compound having an oxetanyl group as the compound (B) include 3-ethyl-3-(hydroxymethyl)oxetane (3-ethyl-3-(hydroxymethyl)oxetane). , 3-ethyl-3-[(phenoxy)methyl]oxetane, 3-ethyl-3-(hexyloxymethyl)oxetane, 3-ethyl-3- (2-ethylhexyloxymethyl)oxetane, 3-ethyl-3-(chloromethyl)oxetane, 1,4-bis[(3-ethyl-3-oxo) Heterocyclic butylmethoxy)methyl]benzene and bis{[1-ethyl(3-oxetanyl)]methyl}ether and the like.

As the compound (B), examples of the compound having an alkoxyalkylalkyl group include methyltrimethoxydecane, ethyltrimethoxydecane, butyltrimethoxydecane, tetramethoxydecane, and tetraethoxy. Alkoxydecane such as decane, N-(2-aminoethyl)-3-aminopropylmethyldimethoxydecane, 3-aminopropyltriethoxydecane, 3-aminopropyl Trimethoxy decane and the like.

As the compound (B), examples of the compound having a hydroxyl group include amyl alcohol, octyl alcohol, lauryl alcohol, myristyl alcohol, and stearyl alcohol. ), behenyl alcohol, oleyl alcohol, hexanediol, glycerin, monoethanolamine, diethanolamine, triethanolamine, benzyl alcohol Benzyl alcohol, phenethyl alcohol, and the like.

The compound (B) described above may be used singly or in combination of two or more kinds in the ink composition of the present invention.

Further, when the content of the compound (B) is 15% by weight to 50% by weight based on the total amount of the ink composition of the present invention, the plating resistability, heat resistance and adhesion to the substrate of the cured film obtained from the composition are excellent. The affinity is improved, so it is preferably 15 wt% to 45 wt%, more preferably 15 wt% to 40 wt%.

<1.3. Compound (C) having at least one polymerizable group selected from the group consisting of (meth) acryloyl group, allyl group and vinyl group>

As described above, the photocurable ink composition for inkjet according to the present invention may contain the compound (C).

The compound (C) is a compound other than the above compound (B), and is a compound having at least one polymerizable group selected from the group consisting of a (meth) acryl fluorenyl group, an allyl group, and a vinyl group. There is no special limit.

When the compound (C) is contained in the ink composition of the present invention, the photocurability of the ink composition is improved, and the viscosity of the ink composition is lowered, and the ejection property of the ink composition is improved. Therefore, the compound (C) can be used as a photocurable diluted monomer in the ink composition of the present invention.

When the amount of the polymerizable group in the compound (C) is large, the crosslinking density is improved in the cured film obtained by photocuring the ink composition of the present invention, and the heat resistance and plating resistance of the cured film are improved. . The number of the polymerizable groups in the compound (C) is usually 6 or less.

In addition, among the above-mentioned polymerizable groups, among the three kinds of polymerizable groups, a (meth)acryl fluorenyl group is particularly preferable.

Specific examples of the compound having a (meth) acrylonitrile group include isomeric cyanuric acid ethylene oxide modified di(meth)acrylate, pentaerythritol di(meth)acrylate, and pentaerythritol di(methyl). Acrylate monostearate, pentaerythritol tri(meth)acrylate, trimethylolpropane di(meth)acrylate, dipentaerythritol di(meth)acrylate, dipentaerythritol tri(meth)acrylate, Dipentaerythritol tetra(meth)acrylate, glycidyl (meth)acrylate, 3,4-epoxycyclohexyl (meth)acrylate, methyl glycidyl (meth)acrylate, (meth)acrylic acid , methyl (meth) acrylate, ethyl (meth) acrylate, isopropyl (meth) acrylate, butyl (meth) acrylate, isobutyl (meth) acrylate, third (meth) acrylate Butyl ester, 2-hydroxyethyl (meth)acrylate, cyclohexyl (meth)acrylate, tetrahydrofurfuryl (meth)acrylate, benzyl (meth)acrylate, dicyclopentene (meth)acrylate Oxyethyl ester, isobornyl (meth)acrylate, phenyl (meth)acrylate, glycerol mono(meth)acrylate, bisphenol F-type ethylene oxide Diacrylate, bisphenol A type ethylene oxide modified diacrylate, dipropylene glycol diacrylate, polyethylene glycol diacrylate, polypropylene glycol diacrylate, 1,4-butanediol diacrylate, 1,6-hexanediol diacrylate, 1,9-nonanediol diacrylate, 1,4-cyclohexanedimethanol diacrylate, 2-n-butyl-2-ethyl-1,3- Propylene glycol diacrylate, trimethylolpropane tri(meth)acrylate, ethylene oxide modified trimethylolpropane tri(meth)acrylate, propylene oxide modified trimethylolpropane tris(A) Acrylate, epichlorohydrin modified trimethylolpropane tri(meth)acrylate, di-trimethylolpropane tetra(meth)acrylate, tris(meth)acrylate, Epichlorohydrin modified triglyceride (meth) acrylate, diglycerin tetra (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol hexa (meth) acrylate, caprolactone modified dipentaerythritol Hexa(meth)acrylate, ethylene oxide modified tris(meth)acrylate, and urethane (meth)acrylate.

In the ink composition of the present invention, the compound (C) may be used alone or in combination of two or more.

In addition, when the content of the compound (C) in the ink composition of the present invention is from 20% by weight to 70% by weight based on the total amount of the ink composition, the photocurability and the jettability of the ink composition are improved. The balance with other characteristics is more preferably 20 wt% to 65 wt%, and particularly preferably 20 wt% to 60 wt%.

<1.4. Photopolymerization initiator (D)>

In order to further improve photocurability, the photocurable ink composition for inkjet according to the present invention may further contain a photopolymerization initiator (D). The photopolymerization initiator (D) is not particularly limited as long as it can generate a radical by irradiation with ultraviolet light or visible light, and is preferably an alkylphenone or a decylphosphine oxide (acyl). A phosphine oxide-based or titanocene-based photopolymerizable compound is particularly preferably a fluorenylphosphine oxide-based photopolymerization initiator from the viewpoint of photocurability.

Specific examples of the photopolymerization initiator (D) include benzophenone, Michler's ketone, 4,4'-bis(diethylamino)benzophenone, and oxygen. Xanthone, thioxanthone, isopropyl oxazinone, 2,4-diethylthioxanthone, 2-ethyl anthraquinone, acetophenone Acetphenone), 2-hydroxy-2-methylpropiophenone, 2-hydroxy-2-methyl-4'-isopropylpropiophenone, 1-hydroxycyclohexyl phenyl ketone , isopropyl benzoin ether, isobutyl benzoin ether, 2,2-diethoxyacetophenone, 2,2-dimethoxy-2-phenylacetophenone, camphorquinone ( Camphorquinone), benzantrone, 2-methyl-1-[4-(methylthio)phenyl]-2-morpholinylpropan-1-one, 2-benzyl-2-di Methylamino-1-(4-morpholinylphenyl)-butanone-1,4-dimethylaminobenzoic acid ethyl ester, 4-dimethylaminobenzoic acid isoamyl ester, 4,4 '-Di(t-butylperoxycarbonyl)benzophenone, 3,4,4'-tris(t-butylperoxycarbonyl)benzophenone, 3,3',4,4'-four (t-butylperoxycarbonyl)benzophenone, 3,3',4,4'-tetra(trihexylperoxycarbonyl)benzophenone, 3,3'-bis(methoxycarbonyl)-4,4'-di(t-butylperoxide) Carbonyl)benzophenone, 3,4'-bis(methoxycarbonyl)-4,3'-bis(t-butylperoxycarbonyl)benzophenone, 4,4'-di(methoxy Carbonyl)-3,3'-bis(t-butylperoxycarbonyl)benzophenone, 2-(4'-methoxystyryl)-4,6-bis(trichloromethyl)- Triazine, 2-(3',4'-dimethoxystyryl)-4,6-bis(trichloromethyl)-s-triazine, 2-(2',4'-dimethoxy Styryl)-4,6-bis(trichloromethyl)-s-triazine, 2-(2'-methoxystyryl)-4,6-bis(trichloromethyl)-s-triazine , 2-(4'-pentyloxystyryl)-4,6-bis(trichloromethyl)-s-triazine, 4-[p-N,N-di(ethoxycarbonylmethyl)] -2,6-bis(trichloromethyl)-s-triazine, 1,3-bis(trichloromethyl)-5-(2'-chlorophenyl)-s-triazine, 1,3-double ( Trichloromethyl)-5-(4'-methoxyphenyl)-s-triazine, 2-(p-dimethylaminostyryl)benzoxazole, 2-(p-dimethylamino) Styryl)benzothiazole, 2-mercaptobenzothiazole, 3,3'-carbonylbis(7-diethylaminocoumarin), 2-(o-chlorophenyl)-4,4',5 , 5'-tetraphenyl -1,2'-biimidazole, 2,2'-bis(2-chlorophenyl)-4,4',5,5'-tetrakis(4-ethoxycarbonylphenyl)-1,2'- Biimidazole, 2,2'-bis(2,4-dichlorophenyl)-4,4',5,5'-tetraphenyl-1,2'-biimidazole, 2,2'-bis (2 ,4-dibromophenyl)-4,4',5,5'-tetraphenyl-1,2'-biimidazole, 2,2'-bis(2,4,6-trichlorophenyl)- 4,4',5,5'-tetraphenyl-1,2'-biimidazole, 3-(2-methyl-2-dimethylaminopropionyl)carbazole, 3,6-bis ( 2-methyl-2-morpholinylpropanyl)-9-n-dodecylcarbazole, 1-hydroxycyclohexyl phenyl ketone, bis(η ⁵ -2,4-cyclopentadiene-1- Bis(2,6-difluoro-3-(1H-pyrrol-1-yl)-phenyl)titanium, bis(2,4,6-trimethylbenzylidene)phenylphosphine oxide, 2,4,6-trimethylbenzimidyldiphenylphosphine oxide, oxyphenylacetic acid, 2-[2-oxo-2-phenylethenyloxyethoxy]ethyl ester, 2- (2-hydroxyethoxy)ethyl ester, 2-(dimethylamino)-2-[(4-methylphenyl)methyl]-1-[4-(4-morpholinyl)phenyl ]-1-butanone, 1,2-octanedione, 1-[4-(phenylthio)-, 2-(O-benzylidenehydrazine), ethyl ketone, 1-[9-ethyl -6-(2-methylbenzhydryl)-9H-indazol-3-yl]-,1-(O-ethylindenyl), 2-hydroxy-1-{4-[4-(2 -hydroxy-2-methyl-propenyl)-benzyl]phenyl} 2-methyl-propan-1-one, 2,2-dimethoxy-1,2-diphenylethane-1-one, and methyl phenylglyoxylate.

In the ink composition of the present invention, the photopolymerization initiator (D) may be used singly or in combination of two or more.

When the content of the photopolymerization initiator (D) in the ink composition of the present invention is from 0.5% by weight to 20% by weight based on the total amount of the ink composition, the ink composition is highly sensitive to ultraviolet rays, and thus it is preferable. More preferably, it is 1 wt% to 15 wt%, and particularly preferably 2 wt% to 10 wt%.

<1.5. Flame Retardant (E)>

The photocurable ink composition for inkjet according to the present invention may contain a flame retardant (E). In the present specification, the flame retardant (E) is not particularly limited as long as it is a compound capable of imparting flame retardancy, and is preferably organic phosphorus from the viewpoint of low toxicity, low pollution, and safety. A flame retardant is used as the flame retardant (E). Further, a compound having a (meth) acrylonitrile group is also present in the flame retardant, and such a flame retardant does not conform to the above compound (C) in the present specification, but conforms to the flame retardant (E).

Specific examples of the organic phosphorus-based flame retardant include triphenyl phosphate, tricresyl phosphate, tris(xylylene) phosphate, tolylphenyl phosphate, 2-ethylhexyl diphenyl phosphate, and 9,10. -1,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide, 10-(2,5-dihydroxyphenyl) -10H-9-oxa-10-phosphaphenanthrene-10-oxide and condensed 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide.

Among these flame retardants, in particular, the condensed 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide HFA-3003 represented by the following formula (E-1) is used. In the case where the cured film obtained from the ink composition of the present invention is exposed to a high temperature, the flame retardant (E) does not bleed out, which is preferable.

In the ink composition of the present invention, the flame retardant (E) may be used singly or in combination of two or more.

The flame retardant (E) described above can be produced by a known method, and is also commercially available as HFA-3003 manufactured by Showa Denko Electric Co., Ltd. as described above.

In the ink composition of the present invention, when the content of the flame retardant (E) is 5 wt% to 25 wt% of the total amount of the ink composition, the plating resistance of the cured film obtained from the ink composition And a good balance of heat resistance and sprayability, and excellent in flame retardancy, and therefore more preferably, it is 7 wt% to 20 wt%, particularly preferably 10 wt% to 20 wt%, and particularly preferably 12 wt% to 20 wt%. Wt%.

<1.6. At least one compound (F) selected from the group consisting of an epoxy hardener, a melamine resin, and a phenol resin other than the compound (A)

As described above, the photocurable ink composition for inkjet according to the present invention may further contain at least one compound (F) selected from the group consisting of epoxy hardeners, melamine resins, and phenol resins other than the compound (A). .

(1.6.1. Epoxy hardener)

In the case where the ink composition of the present invention contains an epoxy compound as the compound (B) or the like, in order to further improve the plating resistance and heat resistance of the cured film obtained from the ink composition, the ink composition may be further included. An epoxy curing agent other than the compound (A).

Specific examples of the epoxy curing agent include maleic anhydride, methyl maleic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, and methylhexahydrophthalic anhydride. , hexahydrotrimellitic anhydride, phthalic anhydride, trimellitic anhydride, styrene-maleic anhydride copolymer, di-ethyltriamine, tri-ethyltetramine, tetraethylidene pentaamine , dicyandiamide, polyamidamine (polyamide resin), ketimine compound, isophorone diamine, m-xylene diamine, meta-phenylenediamine, 1,3-bis (amino group) Methyl)cyclohexane, N-aminoethylpiperazine, 4,4'-diaminodiphenylmethane, 4,4'-diamino-3,3'-diethyldiphenylmethane , diaminodiphenyl hydrazine, phthalic anhydride, pyromellitic anhydride, methyltetrahydrophthalic anhydride, 3,6-endomethylenetetrahydrophthalic anhydride, hexachloro Methylenetetrahydrophthalic anhydride and methyl-3,6-endomethylenetetrahydrophthalic anhydride.

In the ink composition of the present invention, the epoxy curing agent may be used singly or in combination of two or more kinds.

When the content of the epoxy curing agent in the ink composition of the present invention is from 0.5% by weight to 50% by weight based on the total amount of the ink composition, the plating resistance and heat resistance of the cured film obtained from the ink composition It is preferable to increase, and it is more preferably 0.5 wt% to 40 wt%, and particularly preferably 0.5 wt% to 30 wt%, in consideration of balance with other characteristics.

(1.6.2. Melamine resin)

The photocurable ink composition for inkjet according to the present invention may contain a melamine resin in order to improve plating resistance and heat resistance.

The melamine resin is not particularly limited as long as it is a resin produced by polycondensation of melamine and formaldehyde, and specific examples thereof include methylol melamine, etherified methylol melamine, benzoguanamine, and hydroxymethylbenzene. And decylamine, etherified methylol benzoguanamine, and condensates thereof. In the specific examples, when the etherified methylol melamine is contained, the cured ink film having good plating resistance can be obtained from the ink composition of the present invention.

Further, specific examples of commercially available melamine resins include Nikalac MW-30, Nikalac MW-30HM, Nikalac MW-390, Nikalac MW-100LM, and Nikalac MX-750LM (trade name, Sanwa Chemical (Sanwa Chemical) ( Stock) manufacturing).

In the ink composition of the present invention, the melamine resin may be used singly or in combination of two or more.

When the content of the melamine resin in the ink composition of the present invention is from 0.5% by weight to 255% by weight based on the total amount of the ink composition, the plating resistance and heat resistance of the cured film obtained from the ink composition are improved. Therefore, it is preferably from 1.0 wt% to 20 wt%, more preferably from 1.5 wt% to 20 wt%, in consideration of balance with other characteristics.

(1.6.3. Phenol resin)

The photocurable ink composition for inkjet according to the present invention may contain a phenol resin in order to improve the plating resistance and heat resistance of the cured film obtained from the ink composition.

The phenol resin is preferably a phenol resin obtained by a condensation reaction of an aromatic compound having a phenolic hydroxyl group with an aldehyde, a homopolymer of a vinyl phenol (including a hydride), or a vinyl phenol and may be co-polymerized therewith. A vinyl phenol-based copolymer (including a hydride) of a polymerized compound or the like.

Specific examples of the aromatic compound having a phenolic hydroxyl group include phenol, o-cresol, m-cresol, p-cresol, o-ethylphenol, m-ethylphenol, p-ethylphenol, o-butylphenol, and Butyl phenol, p-butyl phenol, o-xylenol, 2,3-xylenol, 2,4-xylenol, 2,5-xylenol, 3,4-xylenol, 3,5- Xylenol, 2,3,5-trimethylphenol, 3,4,5-trimethylphenol, p-phenylphenol, resorcinol, hydroquinone, hydroquinone monomethyl Hydroquinone monomethylether, pyrogallol, bisphenol A, bisphenol F, terpene-containing diphenol, gallic acid, gallic acid ester, alpha-naphthol and beta - Naphthol.

Similarly, examples of the aldehydes include formaldehyde, para-formaldehyde, furfural, benzaldehyde, nitrobenzaldehyde, and acetaldehyde.

Specific examples of the compound copolymerizable with the vinyl phenol include (meth)acrylic acid or a derivative thereof, styrene or a derivative thereof, maleic anhydride, vinyl acetate, and acrylonitrile.

Specific examples of the commercial product of the phenol resin described above include Resitop PSM-6200 (trade name, manufactured by Kyoei Chemical Co., Ltd.), Shonol BRG-555 (trade name, manufactured by Showa Denko), Maruka Lyncur MS-2P, Maruka Lyncur CST70 and Maruka Lyncur PHM-C (trade name, manufactured by Maruzen Petrochemical Co., Ltd.).

In the ink composition of the present invention, the phenol resin may be used singly or in combination of two or more kinds.

When the content of the phenol resin in the ink composition of the present invention is from 0.5% by weight to 20% by weight based on the total amount of the ink composition, the plating resistance and heat resistance of the cured film obtained from the ink composition are improved. Therefore, it is preferably from 0.5 wt% to 10 wt%, more preferably from 0.5 wt% to 7 wt%, in consideration of balance with other characteristics.

<1.7. Other ingredients>

In order to further improve various characteristics, the photocurable ink composition for inkjet according to the present invention may contain a colorant, a solvent, a surfactant, a polymerization inhibitor, and the like.

(1.7.1. Colorants)

For example, in order to form a cured film from the ink composition on the substrate and to easily distinguish the substrate from the substrate when the cured film is inspected, the inkjet photocurable ink composition of the present invention may contain a colorant. The colorant is preferably a dye and a pigment.

In the ink composition of the present invention, the coloring agent may be used singly or in combination of two or more.

When the content of the coloring agent in the ink composition of the present invention is from 0.1% by weight to 5% by weight based on the total amount of the ink composition, the cured film is easily inspected, so that it is preferable to consider the balance with other characteristics. More preferably, it is 0.1 wt% to 1 wt%, and particularly preferably 0.1 wt% to 0.5 wt%.

(1.7.2. Solvents)

The photocurable ink composition for inkjet according to the present invention has sufficient ejection properties even if it does not contain a solvent (water or an organic solvent), and therefore is an ink composition which is easy to design and has a low environmental load, and in order to further improve the ejection property, A solvent may be included.

With regard to the above solvent, when the ink composition of the present invention is sprayed, in the case of heating the ink jet head, if the ink composition contains a solvent having a low boiling point, the solvent is volatilized, and the viscosity of the ink composition rises, resulting in an ink jet head. The condition of the nozzle opening is blocked. Therefore, a solvent having a boiling point of from 100 ° C to 300 ° C is preferred.

Specific examples of the solvent having a boiling point of 100 ° C to 300 ° C include butyl acetate, butyl propionate, ethyl lactate, methyl oxyacetate, ethyl oxyacetate, butyl oxyacetate, methyl methoxyacetate, Ethyl methoxyacetate, butyl methoxyacetate, methyl ethoxyacetate, ethyl ethoxyacetate, methyl 3-oxopropionate, ethyl 3-oxopropionate, 3-methoxypropane Methyl ester, ethyl 3-methoxypropionate, methyl 3-ethoxypropionate, ethyl 3-ethoxypropionate, methyl 2-oxopropionate, ethyl 2-oxopropionate, Propyl 2-oxopropionate, methyl 2-methoxypropionate, ethyl 2-methoxypropionate, propyl 2-methoxypropionate, methyl 2-ethoxypropionate, 2- Ethyl ethoxypropionate, methyl 2-oxy-2-methylpropanoate, ethyl 2-oxy-2-methylpropionate, methyl 2-methoxy-2-methylpropionate , 2-ethoxy-2-methylpropionic acid ethyl ester, methyl pyruvate, ethyl pyruvate, propyl pyruvate, methyl acetate, ethyl acetate, 2-butoxybutyric acid Ester, ethyl 2-oxobutanoate, dioxane, ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, dipropylene glycol, tripropylene glycol, 1,4-butanediol, Glycol monoisopropyl ether, ethylene glycol monobutyl ether, propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, propylene glycol monopropyl ether acetate, dipropylene glycol monoethyl ether acetate, Dipropylene glycol monobutyl ether acetate, ethylene glycol monobutyl ether acetate, cyclohexanone, cyclopentanone, diethylene glycol monomethyl ether, diethylene glycol monomethyl ether acetate, diethylene glycol Monoethyl ether, diethylene glycol monoethyl ether acetate, diethylene glycol monobutyl ether, acetate, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol methyl ether, diethyl Glycol monobutyl ether acetate, γ-butyrolactone, N,N-dimethylacetamide, N-methyl-2-pyrrolidone and dimethylimidazolidinone.

These solvents may be used alone or in combination of two or more.

When the content of the solvent in the ink composition of the present invention is from 0 wt% to 60 wt% of the total amount of the ink composition, the balance between the sprayability and other characteristics is good, and more preferably from 0 wt% to 50 wt%. Preferably, it is 0 wt% to 40 wt%.

(1.7.3. Surfactant)

The inkjet photocurable ink composition of the present invention may contain a surfactant in order to improve the wettability to the base substrate or the film surface uniformity of the cured film obtained from the ink composition. In the present invention, the surfactant is a ruthenium-based surfactant, an acrylic surfactant, a fluorine-based surfactant, or the like.

Specific examples of the above-mentioned lanthanoid surfactants include Byk-300, Byk-306, Byk-335, Byk-310, Byk-341, Byk-344, and Byk-370 (trade name, BYK-Chemical Japan (BYK-Chemie) Japan) (manufactured by the company); specific examples of the acrylic surfactant described above include Byk-354, Byk-358, and Byk-361 (trade name, manufactured by BYK-Chemie Japan Co., Ltd.); the above-mentioned fluorine-based surfactant Specific examples thereof include DFX-18, Ftergent 250, and Ftergent 251 (trade name, manufactured by Neos), and Megafac F-477, Megafac 479, Megafac 553, Megafac 554, RS-72-K, and RS-211 ( Trade name, DIC (share) manufacturing).

In the ink composition of the present invention, the surfactant may be used singly or in combination of two or more.

When the content of the surfactant in the ink composition of the present invention is from 0.001% by weight to 1% by weight based on the total amount of the ink composition, the uniformity of the film surface of the cured film obtained from the ink composition is improved, so Preferably, it is more preferably from 0.001 wt% to 0.1 wt%, particularly preferably from 0.001 wt% to 0.05 wt%, in consideration of balance with other characteristics.

(1.7.4. Polymerization inhibitors)

In order to improve storage stability, the photocurable ink composition for inkjet according to the present invention may contain a polymerization inhibitor.

Specific examples of the polymerization inhibitor include 4-methoxyphenol, hydroquinone, and phenothiazine. In these examples, when phenothiazine is contained, the ink composition of the present invention preferably has a small change in viscosity during long-term storage.

In the ink composition of the present invention, the polymerization inhibitor may be used singly or in combination of two or more kinds.

If the content of the polymerization inhibitor in the ink composition of the present invention is from 0.01% by weight to 1% by weight based on the total amount of the ink composition, the change in viscosity of the ink composition during long-term storage is small, so that it is preferred. If it considers the balance with other characteristics, it is more preferably 0.01 wt% to 0.5 wt%.

<1.8. Viscosity of Photocurable Ink Composition for Inkjet>

The viscosity of the photocurable ink composition for inkjet according to the present invention is measured at 25 ° C using an E-type viscometer and is 200 mPa ‧ s or less. Therefore, the ink composition of the present invention has excellent ejection properties even without a solvent. Further, the above ink composition may contain a solvent as needed, as described above.

From the viewpoint of ejectability, the viscosity of the ink composition of the present invention is preferably from 2 mPa ‧ to 200 mPa ‧ , more preferably from 10 mPa ‧ to 180 mPa ‧ , and particularly preferably from 20 mPa ‧ s 150 mPa‧s.

Further, in the case of using an ink composition having a viscosity at 25 ° C of more than 30 mPa ‧ s, if the ink jet head is heated to lower the viscosity at the time of discharge, it can be ejected more stably. In the case of spraying by heating the ink jet head, the viscosity of the ink composition of the present invention at a heating temperature (preferably 40 ° C to 120 ° C) is preferably from 1 mPa ‧ to 30 mPa ‧ s, particularly preferably 2 mPa‧s ~ 25 mPa‧s, especially 3 mPa‧s ~ 20 mPa‧s.

In the case of warming the ink jet head, it is preferred to use a solvent-free ink composition as the ink composition of the present invention. In this case, the viscosity of the ink composition is preferably adjusted by appropriately selecting the type and content of the diluent (compound (C)). Further, in the case where a solvent is contained, it is preferred to use a solvent having a boiling point of from 100 ° C to 300 ° C as described above.

On the other hand, in the case where the ink jet head is not heated, the viscosity of the ink composition can be adjusted by adding a solvent so that the amount of the solvent is 60 wt% or less of the total amount of the ink composition.

<1.9. Preparation method of photocurable ink composition for inkjet according to the present invention>

The photocurable ink composition for inkjet according to the present invention can be produced by mixing the components which are raw materials by a known method. In particular, the ink composition of the present invention preferably has the above-mentioned (A) component, (B) component, and optionally the above-mentioned (C) component to (F) component or other components, and the resulting solution is filtered. And degassed to prepare.

For example, the ink composition of the present invention prepared as described above is excellent in ejectability and photocurability, and can form a cured film which is excellent in plating resistance, heat resistance, adhesion to a substrate, and flame retardancy. Further, for the above filtration, for example, a membrane filter made of a fluororesin or the like is used.

<1.10. Preservation of the photocurable ink composition for inkjet according to the present invention>

When the inkjet ink of the present invention is stored at -20 ° C to 25 ° C, the viscosity change (increased) during storage is small, and the storage stability is good.

[2. Coating of photocurable ink composition for inkjet of the present invention by an inkjet method]

The photocurable ink composition for inkjet according to the present invention can be applied by a known inkjet coating method. The inkjet coating method includes, for example, a method in which mechanical energy is applied to an ink composition to eject (coat) an ink composition from an inkjet head (so-called piezoelectric method); and thermal energy is applied to the ink composition to eject ink. Method of composition (so-called bubble (registered trademark) method).

The inkjet photocurable ink composition of the present invention can be applied in advance to a predetermined pattern by using an inkjet coating method. Thereby, the ink can be applied only to the necessary portions, and the cost is reduced as compared with the photolithography method.

The coating unit which is preferably used for coating the photocurable ink composition for inkjet according to the present invention is, for example, an ink jet unit including an ink containing portion for storing the ink compositions and an ink jet head. For example, the inkjet module may be an inkjet module that applies thermal energy corresponding to a coating signal to the ink composition, and performs coating corresponding to the coating signal while generating droplets of the ink composition using the energy. (draw).

The ink jet head may, for example, be an ink jet head having a liquid contact surface of a heat generating portion containing a metal and/or a metal oxide. Specific examples of the metal and/or metal oxide include metals such as Ta, Zr, Ti, Ni, and Al, and oxides of these metals.

For the application of the ink composition of the present invention, a preferred coating apparatus includes, for example, an ink composition in an ink jet head having an ink containing portion that accommodates an ink composition, and a coating composition. The energy corresponding to the cloth signal is applied (painting) corresponding to the coating signal while generating droplets of the ink composition by the energy.

The inkjet coating device is not limited to a device in which the inkjet head is separated from the ink containing portion, and an apparatus in which the inkjet head is inseparably integrated with the ink containing portion may be used. In addition, the ink accommodating portion may be attached to the ink accommodating portion of the cradle in addition to the ink accommodating portion that is detachably integrated with the ink jet head or integrated in the cradle, and may be provided at a fixed portion of the device via the ink supply member. For example, the tube supplies the ink composition to the ink jet head in the form of an ink composition.

Further, the heating temperature of the photocurable ink composition for inkjet is preferably from 40 ° C to 120 ° C, and the viscosity of the ink composition at the heating temperature is preferably from 1 mPa ‧ to 30 mPa ‧ s.

<2.1. Formation of hardened film>

After the photocurable ink composition for inkjet according to the present invention is applied onto the surface of the substrate by an inkjet method, the ink composition is irradiated with light such as ultraviolet rays or visible light to cure the coating film, thereby obtaining a cured film.

In the case of irradiating ultraviolet rays, visible light rays, etc., the amount of exposure to be irradiated depends on the composition of the ink composition, and the integrated light meter UIT-201 of the light-receiver UVD-365PD manufactured by the Ushio motor (unit) is mounted. The measurement is preferably from about 10 mJ/cm ² to about 1,000 mJ/cm ² , more preferably from about 20 mJ/cm ² to about 800 mJ/cm ² , and more preferably from about 40 mJ/cm ² to about 500 mJ/cm ² . . Further, the wavelength of the ultraviolet ray or the visible ray to be irradiated is preferably from 250 nm to 500 nm, more preferably from 300 nm to 450 nm.

In addition, the exposure apparatus is not particularly limited as long as it is a device that emits ultraviolet light or visible light in a range of 250 nm to 500 nm, such as a high-pressure mercury lamp, an ultrahigh pressure mercury lamp, a metal halide lamp, or a halogen lamp.

Further, the cured film which is hardened by irradiation with light may be further heated and calcined as needed, and it is particularly preferably heated at 100 ° C to 250 ° C for 10 minutes to 60 minutes, more preferably at 120 ° C to 230 ° The mixture is heated at ° C for 10 minutes to 60 minutes, and more preferably at 150 ° C to 200 ° C for 10 minutes to 60 minutes. The cured film can be hardened more firmly by heating and calcining. Specifically, it is considered that the compound (A) and the compound (B) are reacted by heating or calcination, and it is considered that a solid network in which a plurality of chains obtained by polymerizing the above compound (A) are linked by a compound (B) is considered. Eye structure.

The "substrate" to which the ink composition of the present invention can be applied in the present invention is not particularly limited as long as it can be a target to which the ink composition of the present invention is applied, and the shape thereof is not limited to a flat plate shape, and may be Curved.

Further, the material of the substrate is not particularly limited, and examples thereof include polyester resins such as polyethylene terephthalate (PET) and polybutylene terephthalate (PBT). Polyolefin resin such as ethylene and polypropylene, plastic film such as polyvinyl chloride, fluororesin, acrylic resin, polyamide, polycarbonate and polyimine, cellophane, acetate, metal foil, polyfluorene A laminate film of imine and metal foil, a glasse paper with a filling effect, a parchment paper, and a polyethylene, a clay binder, a polyvinyl alcohol, a starch or a carboxymethyl cellulose. Paper and glass subjected to filling treatment such as (carboxy methyl cellulose, CMC).

Among the substances constituting the substrate, pigments, dyes, antioxidants, anti-deterioration agents, fillers, ultraviolet absorbers, antistatic agents, and/or anti-electromagnetic waves may be further contained within a range that does not adversely affect the effects of the present invention. Additives such as agents. Further, a coating layer or a solder resist film of a material different from the substrate may be formed on a part of the surface of the substrate.

The thickness of the substrate is not particularly limited, but is usually about 10 μm to 2 mm, and is appropriately adjusted depending on the purpose to be used, and is preferably 15 μm to 500 μm, and particularly preferably 20 μm to 200 μm.

When the cured film is formed on the substrate, the water-repellent treatment, the corona treatment, the plasma treatment, or the sandblasting treatment may be performed on the surface of the substrate before the formation of the cured film as needed, and the surface may be easily disposed. Protective film for adhesive layer or color filter.

The use of the substrate is not particularly limited, and the cured film obtained from the photocurable ink composition for inkjet according to the present invention is excellent in plating resistance, heat resistance, adhesion to a substrate, and flame retardancy. An electronic component or the like obtained by mounting an IC wafer or the like on an electronic circuit board having a metal circuit on the surface of the substrate.

The metal forming the above circuit is not particularly limited, and is preferably gold, silver, copper, aluminum or indium tin oxide (ITO). The ink composition of the present invention is applied to a predetermined pattern by an inkjet device on a substrate formed of a wiring including the metal, and is cured. The cured film thus obtained has a cover film as the wiring. Features.

Such an electronic circuit board in which a circuit is formed on the surface of the substrate and at least a part of the substrate and the circuit are formed with the cured film is also included in the scope of the present invention. Further, the thickness of the cured film which functions as a cover film or the like is not particularly limited, but is usually 5 μm to 50 μm.

By mounting an IC chip, a capacitor, a resistor, a fuse, or the like on the electronic circuit board of the present invention manufactured as described above, for example, a liquid crystal display element or an electronic component for an EL display element can be produced.

[Example]

Hereinafter, the present invention will be further illustrated by examples, but the present invention is not limited by the examples.

First, a method of synthesizing the compounds used in Examples 1 to 4 and Comparative Example 2, Comparative Example 3, and Comparative Example 5 will be described. Next, preparation and use of the photocurable ink composition for inkjet using the compound will be described. The obtained cured film pattern forming substrate will be described.

<Synthesis of Compound (A) Represented by General Formula (1)>

[Synthesis example]

To a 50 mL eggplant type flask, 0.15 mol (13.29 g) of β-alanine (manufactured by Tokyo Chemical Industry Co., Ltd.) and 0.15 mol (16.72 g) of methyl maleic anhydride (manufactured by Tokyo Chemical Industry Co., Ltd.) were added. ), stirring at 150 ° C for 3 hours. After stirring, toluene was added to a 50 mL eggplant type flask, and the water generated by the reaction was removed while refluxing for 1 hour.

After the water was removed, toluene was removed from the reaction liquid using a rotary evaporator, whereby 27.37 g of a compound represented by the following formula (hereinafter referred to as "compound A1") was obtained.

<Synthesis of a compound represented by the following formula (2)>

[Comparative Synthesis Example]

Dissolved maleic anhydride 1.0 mol (98.1 g) (manufactured by Tokyo Chemical Industry Co., Ltd.) and p-aminobenzoic acid 1.0 mol (137.1 g) in 320 ml of N,N-dimethylformamide Chemical Industry Co., Ltd.), the resulting solution was stirred at room temperature for 5 hours under a nitrogen atmosphere. After stirring, the above solution was added to a large amount of water to precipitate a reaction product. The precipitate was filtered, dried, and purified by recrystallization in water.

Next, 100 mL of acetic anhydride and 2.5 g of sodium acetate were added to 0.2 mol (43.5 g) of the purified product, and the resulting mixed solution was stirred at 55 ° C to 60 ° C for 2 hours. After stirring, the above mixture was added to a large amount of water to precipitate a reaction product. The obtained precipitate was filtered, washed with water, dried, and recrystallized in a mixed solution of methanol-water (V/V = 6/1) to obtain the target compound (the compound represented by the following formula (2), the following Called "Compound MI" 37.0 g.

<Production of Photocurable Ink Composition for Inkjet and Cured Film Pattern Forming Substrate>

Next, the photocurable ink composition for inkjet produced in Examples 1 to 4 and Comparative Examples 1 to 6 and the cured film pattern forming substrate obtained using the same will be described.

[Example 1]

Compound A1 synthesized in the above synthesis example of the compound (A), bisphenol A type epoxy compound Epikote 828 (trade name, manufactured by Mitsubishi Chemical Corporation) as the compound (B), and A as the compound (C) 2-hydroxyethyl acrylate (trade name: manufactured by Tokyo Chemical Industry Co., Ltd., hereinafter referred to as HEMA), 2,4,6-trimethylbenzimidyl diphenyl as photopolymerization initiator (D) Phosphine oxide DAROCUR TPO (trade name, manufactured by BASF Japan Co., Ltd.) and phenothiazine as a polymerization inhibitor were mixed and dissolved in the following composition ratio, and the obtained composition was filtered through a 1 μm PTFE membrane filter. A photocurable ink composition 1 for inkjet was prepared.

(A) Compound Al 0.6000 g

(B) Epikote 828 0.6000 g

(C) HEMA 0.8000 g

(D) TPO 0.1000 g

Other phenothiazine 0.0010 g

The viscosity of the above ink composition 1 at 25 ° C was measured using an E-type viscometer (TV-22 manufactured by Toki Sangyo Co., Ltd., the same applies hereinafter), and the viscosity was 111 mPa·s.

The ink composition 1 was injected into an ink jet cartridge, and the ink jet cartridge was mounted on an ink jet apparatus (DMP-2831 manufactured by FUJI FILM Dimatix Co., Ltd.), and a discharge voltage (piezoelectric voltage) was 16 using a 10 pl nozzle. V, the nozzle temperature is 70 ° C, the driving frequency is 5 kHz, the number of coating times is 1 time, and the copper-clad laminate Veloflex (trade name, having a copper foil thickness of 35 μm) is laminated on the polyimide. A predetermined pattern is formed on the copper surface of Toyobo Co., Ltd.

On the substrate patterned using the ink composition 1, ultraviolet rays having a wavelength of 365 nm were irradiated with a UV exposure amount of 250 mJ/cm ² , and then heat-hardened at 190 ° C for 30 minutes, thereby obtaining a thickness of 13 μm. The cured film pattern of the substrate 1.

[Example 2]

In Example 1, except that dipropylene glycol diacrylate SR508 (trade name, manufactured by Sartomer Japan Co., Ltd.) was further added as the compound (C) to have the following composition ratio, photohardening for inkjet was prepared in the same manner as in Example 1. Ink composition 2.

(A) Compound A1 0.6000 g

(B) Epikote 828 0.6000 g

(C) HEMA 0.8000 g

(C) SR508 0.4000 g

(D) TPO 0.1200 g

Other phenothiazine 0.0012 g

The viscosity of the above ink composition 2 at 25 ° C was measured using an E-type viscometer, and as a result, the viscosity was 85 mPa ‧ s.

Using the ink composition 2, a substrate 2 formed with a cured film pattern having a thickness of 12 μm was obtained in the same manner as in Example 1.

[Example 3]

In Example 1, except that the condensed 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide HFA-3003 (manufactured by Showa Denko Co., Ltd.) was added as a flame retardant (E) A photocurable ink composition 3 for inkjet was prepared in the same manner as in Example 1 except for the composition ratio.

(A) Compound A1 0.6000 g

(B) Epikote 828 0.6000 g

(C) HEMA 0.8000 g

(D) TPO 0.1200 g

(E) HFA-3003 0.4000 g

Other phenothiazine 0.0012 g

The viscosity of the above ink composition 3 at 25 ° C was measured using an E-type viscometer, and as a result, the viscosity was 135 mPa ‧ s.

Using the ink composition 3, a substrate 3 formed with a cured film pattern having a thickness of 15 μm was obtained in the same manner as in Example 1.

[Example 4]

In Example 1, an inkjet was prepared in the same manner as in Example 1 except that the methylol melamine resin Nikalac MW-30 (trade name, manufactured by Sanwa Chemical Co., Ltd.) was added as the compound (F) to have the following composition ratio. Photocurable ink composition 4.

(A) Compound A1 0.6000 g

(B) Epikote 828 0.6000 g

(C) HEMA 0.8000 g

(D) TPO 0.1200 g

(F) Nikalac MW-30 0.4000 g

Other phenothiazine 0.0012 g

The viscosity of the ink composition 4 at 25 ° C was measured using an E-type viscometer, and as a result, the viscosity was 125 mPa ‧ s.

Using the ink composition 4, a substrate 4 formed with a cured film pattern having a thickness of 13 μm was obtained in the same manner as in Example 1.

[Comparative Example 1]

In Example 1, a photocurable ink composition 5 for inkjet was prepared in the same manner as in Example 1 except that the compound A1 was used instead of the following composition ratio.

(B) Epikote 828 0.6000 g

(C) HEMA 0.8000 g

(D) TPO 0.0700 g

Other phenothiazine 0.0007 g

The viscosity of the ink composition 5 at 25 ° C was measured using an E-type viscometer, and as a result, the viscosity was 61 mPa ‧ s.

Using the ink composition 5, a substrate 5 formed with a cured film pattern having a thickness of 11 μm was obtained in the same manner as in Example 1.

[Comparative Example 2]

In Example 1, a photocurable ink composition 6 for inkjet was prepared in the same manner as in Example 1 except that the following composition ratio was used without using Epikote 828.

(A) Compound A1 0.6000 g

(C) HEMA 0.8000 g

(D) TPO 0.0700 g

Other phenothiazine 0.0007 g

The viscosity of the ink composition 6 at 25 ° C was measured using an E-type viscometer, and as a result, the viscosity was 73 mPa·s.

Using the ink composition 6, a substrate 6 formed with a cured film pattern having a thickness of 12 μm was obtained in the same manner as in Example 1.

[Comparative Example 3]

In Example 1, a photocurable ink composition for inkjet 7 was prepared in the same manner as in Example 1 except that the blending ratio of each component was set to the following composition ratio.

(A) Compound A1 0.6000 g

(B) Epikote 828 0.6000 g

(C) HEMA 0.2000 g

(D) TPO 0.0700 g

Other phenothiazine 0.0007 g

The viscosity of the ink composition 7 at 25 ° C was measured using an E-type viscometer, and as a result, the viscosity was 255 mPa ‧ s.

Using the ink composition 7, inkjet printing was attempted in the same manner as in Example 1, but the ejection property was poor, and a predetermined pattern could not be formed. Therefore, the subsequent test described later was interrupted.

[Comparative Example 4]

In the example 1, except that 2-methylpropenyloxyethylphthalic acid CB-1 (trade name, manufactured by Shin-Nakamura Chemical Co., Ltd.) was used as a substitute for the compound A1, the following composition ratio was obtained. A photocurable ink composition 8 for inkjet was prepared in the same manner as in Example 1.

CB-1 0.6000 g

(B) Epikote 828 0.6000 g

(C) HEMA 0.8000 g

(D) TPO 0.1200 g

Other phenothiazine 0.0012 g

The viscosity of the ink composition 8 at 25 ° C was measured using an E-type viscometer, and as a result, the viscosity was 89 mPa·s.

Using the ink composition 8, a substrate 8 formed with a cured film pattern having a thickness of 12 μm was obtained in the same manner as in Example 1.

[Comparative Example 5]

In Example 1, the compound MI synthesized in the above comparative synthesis example was used as a substitute for the compound A1. However, MI was not dissolved in other components, and the ink composition could not be obtained. Therefore, the subsequent test described later was interrupted.

[Comparative Example 6]

In Example 1, except that N-cyclohexylmethyleneimineimine Imilex-C (trade name, manufactured by Nippon Shokubai Co., Ltd.) was used as a substitute for the compound A1 to have the following composition ratio, The photocurable ink composition 10 for inkjet was prepared in the same manner.

Imilex-C 0.6000 g

(B) Epikote 828 0.6000 g

(C) HEMA 0.8000 g

(D) TPO 0.1200 g

Other phenothiazine 0.0012 g

The viscosity of the ink composition 10 at 25 ° C was measured using an E-type viscometer, and as a result, the viscosity was 92 mPa ‧ s.

Using the ink composition 10, a substrate 10 formed with a cured film pattern having a thickness of 12 μm was obtained in the same manner as in Example 1.

<Evaluation of Photocurable Ink Composition and Patterned Cured Film for Inkjet>

In the production of the cured film pattern forming substrate, and after the production, the inkjet photocurable ink composition is sprayable and photocurable, and the cured film is resistant to plating, adhesion to the substrate, and resistance. Evaluation of flammability and heat resistance. Each test method is as follows, and the evaluation results are shown in Table 1 below.

(Evaluation of the ejection properties of the ink composition)

The disorder of the pattern on the substrate (except Comparative Example 5) obtained in each of the examples and the comparative examples and the whitening of the printing were observed, and the ejection properties of the ink composition were evaluated. The evaluation criteria are as follows.

○: The disorder of the pattern and the whiteness of the printing were not produced at all.

△: The pattern is confusing, and the whiteness of printing is small.

×: The pattern is confusing, and the printing is white.

(Evaluation of light hardenability of ink)

After UV exposure (500 mJ/cm ² ) of the substrate (substrate 1 to substrate 6, substrate 8 and substrate 10) obtained in each of the examples and the comparative examples, the surface was touched with a finger, and the surface state of the cured film was observed under a microscope. The evaluation criteria are as follows. In addition, the light source used for UV exposure was a metal halide lamp MJ-1500L manufactured by Harison Toshiba Lighting Co., Ltd., and the exposure amount was a cumulative light meter UIT- using a light receiver UVD-365PD manufactured by Ushio motor (stock). 201 to determine.

◎: There is no fingerprint touch on the surface of the cured film at all.

○: Only a small amount of finger touch marks remained on the surface of the cured film.

△: Finger touch marks were completely left on the surface of the cured film.

×: Not hardened at all.

(Evaluation of plating resistance)

The cured film pattern forming substrate obtained in each of the examples and the comparative examples (excluding Comparative Example 3 and Comparative Example 5) was poured into a palladium aqueous solution at 30 ° C (trade name: KA'T-450, Pd concentration was 12 mg/L, Shangcun After immersing for 1 minute in industrial (manufactured), it was immersed in an electroless nickel plating solution (trade name: Nimuden NPR-4, Ni concentration: 4.5 g/L, manufactured by Uemura Industrial Co., Ltd.) at 80 ° C for 30 minutes. The water was washed in minutes, and then the surface state of the cured film was observed under a microscope.

Thereafter, the cured film pattern forming substrate was immersed in an electroless gold plating solution (trade name: Goblite TAM-55, Au concentration: 1 g/L, manufactured by Uemura Industrial Co., Ltd.) at 80 ° C for 10 minutes, and then washed with water. , do the same observation. The evaluation criteria are as follows.

◎: No swelling or discoloration or discoloration was observed on the cured film.

○: Although a little discoloration was observed on the cured film, there was no swelling or peeling at all.

△: Many bulging or peeling and discoloration were observed on the cured film.

×: The cured film was completely peeled off.

(evaluation of adhesion)

In order to evaluate the adhesion of the cured film to the copper-clad laminate in the cured film pattern forming substrate obtained in each of the examples and the comparative examples (excluding Comparative Example 3 and Comparative Example 5), the mesh method was carried out (JIS K 5400 (1990). )), investigate whether the cured film is peeled off. The test was carried out under the conditions of a temperature of 25 ° C and a humidity of 65%. The evaluation criteria are as follows.

◎: One of the 100 was not peeled off.

○: One to 20 of 100 were peeled off.

△: 21 to 50 of 100 were peeled off.

×: 51 to 100 peeling off of 100.

(evaluation of flame retardancy)

In order to evaluate the flame retardancy of the cured film obtained from the photocurable ink composition for inkjet, a dressing was used on a Kapton 200H (manufactured by Toray DuPont Co., Ltd.) as a polyimide film (thickness: 50 μm). The ink composition obtained in each of the examples and the comparative examples (excluding Comparative Example 3 and Comparative Example 5) was applied to the surface so that the film thickness was 25 μm, and the irradiation wavelength was 365 nm at an exposure amount of 500 mJ/cm ² . The ultraviolet rays were calcined at 200 ° C for 30 minutes to form a cured film.

Further, a cured film was formed on the back surface of the polyimide film in the same manner as the surface to prepare a test piece. The prepared test piece was cut into a size of 50 mm in width and 200 mm in length, and the test piece was wound into a cylindrical shape in accordance with the VTM test of UL-94 to prepare a sample for combustion test.

The flame with a height of 20 mm is made close to the sample for the combustion test for 3 seconds, and will be extinguished within 5 seconds after leaving the flame. The case where the flame does not reach the height of 125 mm is recorded as "◎", which will not meet the evaluation of ◎, after leaving the flame If it is extinguished within 10 seconds and the flame does not reach the height of 125 mm, it is marked as "○". It will not meet the ○ evaluation. It takes 10 seconds to 1 minute after the flame is extinguished, and the flame reaches the height of 125 mm. △", which does not meet the △ evaluation, does not extinguish even after one minute after leaving the flame, or does not extinguish even after one minute, and the flame reaches a height of 125 mm, which is called "X".

In addition, this evaluation was evaluated based on the vertical burning test of the thin-walled material of UL-94, and the case of "◎" or "○" corresponded to VTM-0.

(Evaluation of heat resistance)

The cured film of the substrate obtained in each of the examples and the comparative examples (excluding Comparative Example 3 and Comparative Example 5) was cut out to 10 mg, respectively, and subjected to a thermogravimetry/differential thermal analysis (TG/DTA) apparatus ( TG/DTA6200, manufactured by SII Nanotechnology Co., Ltd.) The measurement of the thermal weight was carried out. The evaluation result of heat resistance is represented by the temperature at which 5% weight is reduced.

Further, in the case where the above-mentioned cured film is used as a cover film, it is required that the temperature is only 300 ° C or higher when the weight is reduced by 5%.

The results of the above evaluation tests are shown in Table 1.

The substrate 1 to the substrate 4 obtained by using the photocurable ink composition for inkjet of the present invention and the substrate obtained by using the photocurable ink composition for inkjet of the comparative example are shown by the results shown in Table 1. 5. On the substrate 6, the substrate 8, and the substrate 10, no disorder of the pattern and whitening of the printing were observed at all, and the ejection property was good.

On the other hand, the inkjet photocurable ink composition 7 of Comparative Example 3 in which the amount of the compound (C) is small and the viscosity at 25 ° C is as high as 255 mPa ‧ is poor in discharge property, and the printing pattern is disordered and whitened. More, no uniform film was obtained. Therefore, the evaluation other than the ejection property is interrupted.

Then, the photocurability, the nickel plating resistance, and the gold plating resistance of the substrate 1 to the substrate 4, the substrate 5, the substrate 6, the substrate 8, and the substrate 10 were evaluated. As a result, the substrate 1 to the substrate 4 were good. On the other hand, after the Ni plating treatment on the substrate 5 and the substrate 6, the cured film was completely peeled off, and after the Au plating treatment on the substrate 8 and the substrate 10, a lot of swelling and discoloration were observed on the cured film.

In the adhesion test, the substrate 1 to the substrate 4, the substrate 5, the substrate 6, the substrate 8, and the substrate 10 were evaluated in the same manner. As a result, no self-clad copper laminate was observed for the cured films of the substrates 1 to 4. The upper layer is peeled off, but all of the substrate 5, the substrate 6, the substrate 8, and the substrate 10 are peeled off.

As the flame retardancy test, the photocurable ink composition for inkjet 1 to the photocurable ink composition for inkjet 4, the photocurable ink composition for inkjet 5, and the photocurable ink composition for inkjet 6 are used. The photocurable ink composition 8 for inkjet and the photocurable ink composition 10 for inkjet were evaluated. As a result, the ink composition 1 to the ink composition 4 were extinguished within 10 seconds after leaving the flame, and the flame did not reach 125. Mm height. In particular, the ink composition 3 was extinguished within 5 seconds, and the flame retardancy was very good. However, the ink composition 5, the ink composition 6, the ink composition 8, and the ink composition 10 have a height of 125 mm or more within 3 seconds after contact with the flame. Further, the ink composition 8 and the ink composition 10 are extinguished within one minute after leaving the flame, but the ink composition 5 and the ink composition 6 are not extinguished even after one minute or more.

Finally, as a heat resistance test, the temperature at which the cured film obtained from the substrate 1 to the substrate 4, the substrate 5, the substrate 6, the substrate 8, and the substrate 10 was reduced by 5% was measured, and as a result, the substrate 1 to the substrate 4 were obtained. The cured film exceeded 300 ° C, which was a good result.

On the other hand, the cured film obtained from the substrate 5, the substrate 6, the substrate 8, and the substrate 10 could not reach a temperature of 300 ° C when the weight was reduced by 5%.

As described above, according to the present invention, it is possible to provide an inkjet photocurability of a cured film which is excellent in ejectability and photocurability and which is excellent in plating resistance, adhesion to a substrate, flame retardancy, and heat resistance. Ink composition. Since this composition can be ejected without adding water or an organic solvent, it is useful as an ink composition which is easy to design and has a small environmental load.

Claims (12)

A photocurable ink composition for inkjet, comprising: a compound (A) represented by the formula (1): (in the formula (1), R is a divalent organic group having 1 to 100 carbon atoms); and the compound (B) having at least one selected from the group consisting of an oxiranyl group and an oxetanyl group. One type of functional group, and the viscosity of the inkjet photocurable ink composition at 25 ° C is 200 mPa ‧ s or less. The photocurable ink composition for inkjet according to claim 1, wherein in the above formula (1), R is a divalent organic group having 1 to 50 carbon atoms. The photocurable ink composition for inkjet according to claim 2, wherein in the above formula (1), R is an arbitrary discontinuous -CH ₂ - may be an ether bond, an ester bond, or a guanamine The alkyl group having 1 to 50 carbon atoms, the alkylene group having 3 to 50 carbon atoms or the aryl group having 6 to 50 carbon atoms which are substituted by a bond, a urethane bond or a carbonyl group. Photocurable ink for inkjet according to item 3 of the patent application scope In the composition, in the above formula (1), R is an alkylene group having 1 to 50 carbon atoms. The photocurable ink composition for inkjet according to claim 1, wherein the compound (B) has an oxiranyl group. The photocurable ink composition for inkjet according to claim 5, wherein the compound (B) is an epoxy compound, and the epoxy compound has a phenol novolak type, a cresol novolac type, and a bisphenol A. Type, bisphenol F type, hydrogenated bisphenol A type, hydrogenated bisphenol F type, bisphenol S type, bisphenol A phenol type, trisphenol methane type, tetraphenol ethane type, bisphenol type, biphenol type At least one of the group consisting of an alicyclic, heterocyclic, dicyclopentadiene or naphthalene type structure. The photocurable ink composition for inkjet according to claim 1, further comprising a compound (C) other than the above compound (B), wherein the compound (C) has a (meth) acrylonitrile group selected from the group consisting of At least one polymerizable group in the group consisting of allyl groups and vinyl groups. The photocurable ink composition for inkjet according to claim 7, wherein the compound (C) has a (meth) acrylonitrile group. The photocurable ink composition for inkjet according to claim 1, which further comprises a photopolymerization initiator (D). The photocurable ink composition for inkjet according to claim 1, which further comprises a flame retardant (E). The photocurable ink composition for inkjet according to claim 1, further comprising a compound (F) other than the compound (A), wherein the compound (F) is selected from the group consisting of an epoxy hardener and a melamine resin. At least one of the groups consisting of phenol resins. An electronic circuit board characterized in that a circuit is formed on a surface of a substrate, and at least a part of the substrate and the circuit are formed with a cured film, and the cured film is made according to any one of items 1 to 11 of the patent application scope. The inkjet photocurable ink composition according to the item is obtained by curing.