Photocurable resin composition for electronic devices

Abstract

The object of the present invention is to provide a photocurable resin composition for electronic devices having excellent coating properties and curability and having a low dielectric constant. The photocurable resin composition for electronic devices of the present invention contains a curable resin and a polymerization initiator, the curable resin contains a monofunctional polymerizable compound and a polyfunctional cationic polymerizable compound, the monofunctional polymerizable compound contains at least one selected from a monofunctional polymerizable compound having a dicyclopentenyl group that may be substituted, a monofunctional polymerizable compound having a dicyclopentanyl group that may be substituted, and a monofunctional polymerizable compound having a norbornene group that may be substituted, and the dielectric constant of the photocurable resin composition for electronic devices measured under the conditions of 25° C. and 100 kHz is 3.5 or less.

Description

Technical Field

[0001] The present invention relates to a photocurable resin composition for electronic devices having excellent coating properties and curability and a low dielectric constant. Background Art

[0002] In recent years, as a curable resin composition for electronic devices used in adhesives for touch panels, solder resists for circuit boards, and the like, a material having a moderate viscosity, excellent coating properties, and photocurability has been required.

[0003] Touch panels are used in electronic devices such as mobile phones, smartphones, car navigation systems, and personal computers. Among them, electrostatic capacitive touch panels are rapidly gaining popularity due to their excellent functionality.

[0004] An electrostatic capacitive touch panel is generally formed by laminating a cover plate, an adhesive layer, and a substrate. The adhesive layer is required to have excellent transparency and adhesion to an adherend. As such an adhesive layer, for example, Patent Document 1 discloses an adhesive layer comprising a (meth)acrylic polymer obtained by polymerizing a specific monomer component.

[0005] On the other hand, a circuit substrate generally has a circuit based on a wiring pattern formed on a substrate composed of an insulating material, and the outermost surface is coated with a protective film called a solder resist for the purpose of protecting the circuit and insulating the circuit from the outside. In addition, by using a solder resist, when installing components or connecting to external wiring, it is possible to prevent the generation of solder bridges that cause short circuits due to the adhesion of solder between wirings. For example, as disclosed in Patent Document 2, a photosensitive curable resin composition is used to form a pattern.

[0006] Prior art literature

[0007] Patent Literature

[0008] Patent Document 1: Japanese Patent Application Publication No. 2014-034655

[0009] Patent Document 2: Japanese Patent Application Laid-Open No. 08-259663 Summary of the invention

[0010] Problems to be solved by the invention

[0011] In recent years, as capacitive touch panels have become thinner and larger, the curable resin composition used in the adhesive layer is required to have dielectric properties such as a low dielectric constant and a low dielectric loss tangent in order to prevent the response speed of the touch panel from decreasing.

[0012] On the other hand, the curable resin used in the curable resin composition disclosed in Patent Document 2 has a polar group such as an acid group in order to impart photosensitivity, so the dielectric constant and dielectric loss tangent become high, and as a result, there are problems of transmission delay and signal loss when a high-frequency voltage is applied to the circuit. In addition, as a method for easily and effectively forming a fine solder resist pattern, a method of forming a solder resist pattern by printing has been carried out, but in the case of making a conventional curable resin composition into a composition having coating properties suitable for printing by an inkjet method or the like, there is a problem of difficulty in reducing the dielectric constant and dielectric loss tangent.

[0013] An object of the present invention is to provide a photocurable resin composition for electronic devices which has excellent coating properties and curability and has a low dielectric constant.

[0014] Means for solving problems

[0015] The present invention is a photocurable resin composition for electronic devices, characterized in that it contains a curable resin and a polymerization initiator, the curable resin includes a monofunctional polymerizable compound and a polyfunctional cationic polymerizable compound, the monofunctional polymerizable compound includes at least one selected from a monofunctional polymerizable compound having a substituted dicyclopentenyl group, a monofunctional polymerizable compound having a substituted dicyclopentanyl group, and a monofunctional polymerizable compound having a substituted norbornene group, and the dielectric constant of the photocurable resin composition for electronic devices measured under the conditions of 25°C and 100kHz is less than 3.5.

[0016] Hereinafter, the present invention will be described in detail.

[0017] The present inventors have found that a photocurable resin composition for electronic devices having excellent coating properties and curability and a low dielectric constant can be obtained by using a monofunctional polymerizable compound having a specific structure and a polyfunctional cationically polymerizable compound in combination as a curable resin, thereby completing the present invention.

[0018] The photocurable resin composition for electronic devices of the present invention contains a curable resin.

[0019] The curable resin contains a monofunctional polymerizable compound.

[0020] The monofunctional polymerizable compound includes at least one selected from a monofunctional polymerizable compound having a dicyclopentenyl group that may be substituted, a monofunctional polymerizable compound having a dicyclopentyl group that may be substituted, and a monofunctional polymerizable compound having a norbornene group that may be substituted. Hereinafter, the monofunctional polymerizable compound having a dicyclopentenyl group that may be substituted is also referred to as a "monofunctional polymerizable compound containing a dicyclopentenyl group". In addition, hereinafter, the monofunctional polymerizable compound having a dicyclopentyl group that may be substituted is also referred to as a "monofunctional polymerizable compound containing a dicyclopentyl group". In addition, hereinafter, the monofunctional polymerizable compound having a norbornene group that may be substituted is also referred to as a "monofunctional polymerizable compound containing a norbornene group". By containing at least one selected from the above-mentioned monofunctional polymerizable compound containing a dicyclopentenyl group, the above-mentioned monofunctional polymerizable compound containing a dicyclopentanyl group, and the above-mentioned monofunctional polymerizable compound containing a norbornene group, the photocurable resin composition for electronic devices of the present invention has excellent coating properties and a low dielectric constant.

[0021] The monofunctional polymerizable compound has one cationically polymerizable group in one molecule or one radically polymerizable group in one molecule.

[0022] Examples of the cationic polymerizable group possessed by the monofunctional polymerizable compound include epoxy, oxetanyl, vinyl ether, etc., and examples of the radical polymerizable group include acryloyl, methacryloyl, vinyl, allyl, etc. Among them, epoxy, oxetanyl, and acryloyl are preferred.

[0023] Specifically, the above-mentioned monofunctional polymerizable compound preferably includes at least one selected from the group consisting of a compound represented by the following formula (1-1), a compound represented by the following formula (1-2), a compound represented by the following formula (1-3), a compound represented by the following formula (1-4), a compound represented by the following formula (1-5), a compound represented by the following formula (1-6), and a compound represented by the following formula (1-7).

[0024]

Chemical formula 1

[0025]

[0026] The preferred lower limit of the content of the monofunctional polymerizable compound in 100 parts by weight of the curable resin is 20 parts by weight, and the preferred upper limit is 90 parts by weight. By making the content of the monofunctional polymerizable compound within this range, the obtained photocurable resin composition for electronic devices maintains excellent curability, has better coating properties, and has a lower dielectric constant. The more preferred lower limit of the content of the monofunctional polymerizable compound is 30 parts by weight, and the more preferred upper limit is 70 parts by weight.

[0027] The curable resin contains a polyfunctional cationically polymerizable compound.

[0028] By containing the above-mentioned polyfunctional cationically polymerizable compound, the photocurable resin composition for electronic devices of the present invention has excellent curability.

[0029] The polyfunctional cationically polymerizable compound has two or more cationically polymerizable groups in one molecule.

[0030] Examples of the cationically polymerizable group possessed by the polyfunctional cationically polymerizable compound include the same cationically polymerizable groups as those possessed by the monofunctional polymerizable compound, among which an epoxy group and an oxetanyl group are preferred.

[0031] From the perspective of maintaining a low dielectric constant and better curability of the obtained photocurable resin composition for electronic devices, the above-mentioned polyfunctional cationically polymerizable compound preferably includes at least one selected from a polyfunctional alicyclic epoxy compound without a silicone skeleton, a polyfunctional aliphatic glycidyl ether compound without a silicone skeleton, a polyfunctional oxetane compound without a silicone skeleton, and a silicone compound having two or more cationically polymerizable groups.

[0032] The polyfunctional alicyclic epoxy compound not having a silicone skeleton (hereinafter, also simply referred to as a "polyfunctional alicyclic epoxy compound") has an alicyclic epoxy group.

[0033] The polyfunctional alicyclic epoxy compound may have two or more alicyclic epoxy groups in one molecule, or may have one alicyclic epoxy group and one or more non-alicyclic epoxy groups in one molecule.

[0034] Examples of the alicyclic epoxy group include an epoxycyclohexyl group and the like.

[0035] Specific examples of the polyfunctional alicyclic epoxy compound include compounds represented by the following formula (2-1), compounds represented by the following formula (2-2), compounds represented by the following formula (2-3), compounds represented by the following formula (2-4), and 1,2,8,9-diepoxylimonene. Among them, at least one selected from the group consisting of compounds represented by the following formula (2-1), compounds represented by the following formula (2-2), compounds represented by the following formula (2-3), and compounds represented by the following formula (2-4) is preferred, compounds represented by the following formula (2-1) are more preferred, and 3,4,3',4'-diepoxybicyclohexane is further preferred.

[0036]

Chemical formula 2

[0037]

[0038] In formula (2-1), R 1 ~R 18 represents a hydrogen atom, a halogen atom, an oxygen atom, a hydrocarbon group which may have an oxygen atom or a halogen atom, or an alkoxy group which may have a substituent, and each of them may be the same or different.

[0039] In formula (2-2), R 19 ~R 30 represents a hydrogen atom, a halogen atom, an oxygen atom, a hydrocarbon group which may have an oxygen atom or a halogen atom, or an alkoxy group which may have a substituent, and each of them may be the same or different.

[0040] In formula (2-3), R 31 ~R 48 represents a hydrogen atom, a halogen atom, an oxygen atom, a hydrocarbon group which may have an oxygen atom or a halogen atom, or an alkoxy group which may have a substituent, and each of them may be the same or different.

[0041] In formula (2-4), R 49 ~R 66 represents a hydrogen atom, a halogen atom, an oxygen atom, a hydrocarbon group which may have an oxygen atom or a halogen atom, or an alkoxy group which may have a substituent, and each of them may be the same or different.

[0042] The compound represented by the above formula (2-1), the compound represented by the above formula (2-2), the compound represented by the above formula (2-3) and the compound represented by the above formula (2-4) can be produced by the methods disclosed in Japanese Patent No. 5226162, Japanese Patent No. 5979631, etc., for example.

[0043] Examples of commercially available products of the compound represented by the above formula (2-1) include CELLOXIDE 8000 (manufactured by Daicel Corporation).

[0044] Examples of commercially available products of the compound represented by the above formula (2-2) include THI-DE (manufactured by JXTG Energy Co., Ltd.) and the like.

[0045] Examples of commercially available products of the compound represented by the above formula (2-3) include DE-102 (manufactured by JXTG Energy Co., Ltd.) and the like.

[0046] Examples of commercially available products of the compound represented by the above formula (2-4) include DE-103 (manufactured by JXTG Energy Co., Ltd.) and the like.

[0047] The polyfunctional aliphatic glycidyl ether compound not having a silicone skeleton (hereinafter, also simply referred to as a “polyfunctional aliphatic glycidyl ether compound”) has an aliphatic skeleton.

[0048] The polyfunctional aliphatic glycidyl ether compound may have only a linear or branched aliphatic skeleton as the aliphatic skeleton, or may have a cyclic aliphatic skeleton as the aliphatic skeleton.

[0049] Specific examples of the polyfunctional aliphatic glycidyl ether compound include 1,6-hexanediol diglycidyl ether, neopentyl glycol diglycidyl ether, cyclohexanedimethanol diglycidyl ether, and tricyclodecanediol diglycidyl ether.

[0050] As the above-mentioned multifunctional oxetane compound not having a silicone skeleton (hereinafter, also simply referred to as "multifunctional oxetane compound"), specific examples include 3-ethyl-3-(((3-ethyloxetane-3-yl)methoxy)methyl)oxetane, 1,4-bis(((3-ethyloxetane-3-yl)methoxy)methyl)benzene, and bis((3-ethyloxetane-3-yl)methyl)isophthalate.

[0051] Examples of the silicone compound having two or more cationically polymerizable groups include a compound represented by the following formula (3), a compound represented by the following formula (4), and a compound represented by the following formula (5).

[0052]

Chemical formula 3

[0053]

[0054] In formula (3), R 67 Each independently represents an alkyl group having 1 to 10 carbon atoms, R 68 Each independently represents a linking bond or an alkylene group having 1 to 6 carbon atoms, X represents a group containing an epoxy group, a group containing an oxetanyl group, or a group containing a vinyl ether group, and n represents an integer of 0 to 1000.

[0055]

Chemical formula 4

[0056]

[0057] In formula (4), R 69 Each independently represents an alkyl group having 1 to 10 carbon atoms, R 70 represents a linking bond or an alkylene group having 1 to 6 carbon atoms, R 71Each independently represents an alkyl group having 1 to 10 carbon atoms, a group containing an epoxy group, a group containing an oxetane group, or a group containing a vinyl ether group, X represents a group containing an epoxy group, a group containing an oxetane group, or a group containing a vinyl ether group. l represents an integer from 0 to 1000, and m represents an integer from 1 to 100. 71 When all of them are alkyl groups having 1 to 10 carbon atoms, m represents an integer of 2 to 100.

[0058]

Chemical formula 5

[0059]

[0060] In formula (5), R 72 each independently represents an alkyl group having 1 to 10 carbon atoms, a group containing an epoxy group, a group containing an oxetanyl group, or a group containing a vinyl ether group, 2k R 72 At least 2 R's 72 represents an epoxy group-containing group, an oxetanyl group-containing group or a vinyl ether group. k represents an integer of 3 or more and 6 or less.

[0061] As X in the above formula (3), R in the above formula (4) 71 and X, and R in the above formula (5) 72 The epoxy group-containing group is preferably a group represented by the following formula (6-1) or (6-2).

[0062] As X in the above formula (3), R in the above formula (4) 71 and X, and R in the above formula (5) 72 The above-mentioned group containing an oxetanyl group is preferably a group represented by the following formula (7).

[0063] As X in the above formula (3), R in the above formula (4) 71 and X, and R in the above formula (5) 72 The group containing a vinyl ether group is preferably a group represented by the following formula (8).

[0064]

Chemical formula 6

[0065]

[0066] In formulas (6-1) and (6-2), R 73 represents a connecting bond or an alkylene group having 1 to 6 carbon atoms which may have an oxygen atom, and * represents a bonding position.

[0067]

Chemical formula 7

[0068]

[0069] In formula (7), R 74 represents a linking bond or an alkylene group having 1 to 6 carbon atoms which may have an oxygen atom, R 75 represents a hydrogen atom or an alkyl group having 1 to 10 carbon atoms, and * represents a bonding position.

[0070]

Chemical formula 8

[0071] *-R 76 -O-CH=CH2 (8)

[0072] In formula (8), R 76 represents a connecting bond or an alkylene group having 1 to 6 carbon atoms which may have an oxygen atom, and * represents a bonding position.

[0073] The polyfunctional cationically polymerizable compound preferably includes at least one selected from the group consisting of the compound represented by the above formula (2-1), the compound represented by the above formula (2-2), the compound represented by the above formula (2-3), the compound represented by the above formula (2-4), the compound represented by the above formula (3), the compound represented by the above formula (4), and the compound represented by the above formula (5). In particular, from the perspective that the obtained photocurable resin composition for electronic devices can further reduce the dielectric constant and has better low outgassing properties, the polyfunctional cationically polymerizable compound preferably includes at least one selected from the group consisting of the compound represented by the above formula (3), the compound represented by the above formula (4), and the compound represented by the above formula (5).

[0074] The preferred lower limit of the content of the above-mentioned multifunctional cationic polymerizable compound in 100 parts by weight of the above-mentioned curable resin is 10 parts by weight, and the preferred upper limit is 80 parts by weight. By making the content of the above-mentioned multifunctional cationic polymerizable compound within this range, the obtained photocurable resin composition for electronic devices maintains excellent coating properties and low dielectric constant, and has better curability. The more preferred lower limit of the content of the above-mentioned multifunctional cationic polymerizable compound is 30 parts by weight, and the more preferred upper limit is 70 parts by weight.

[0075] The ratio of the monofunctional polymerizable compound to the polyfunctional cationic polymerizable compound (monofunctional polymerizable compound: polyfunctional cationic polymerizable compound) is preferably 1:9 to 9:1 by weight. By making the ratio of the monofunctional polymerizable compound to the polyfunctional cationic polymerizable compound within this range, the obtained resin composition for electronic devices maintains a low dielectric constant, and suppresses damage to components and the generation of outgassing, thereby having better reliability. The ratio of the monofunctional polymerizable compound to the polyfunctional cationic polymerizable compound is more preferably 3:7 to 7:3.

[0076] The curable resin may contain other curable resins in addition to the monofunctional polymerizable compound and the polyfunctional cationically polymerizable compound for the purpose of improving coating properties by adjusting the viscosity, within a range not hindering the purpose of the present invention.

[0077] Examples of the other curable resins include (meth)acrylic compounds and the like.

[0078] In the present specification, the above-mentioned “(meth)acrylic acid” refers to acrylic acid or methacrylic acid, the “(meth)acrylic compound” refers to a compound having a (meth)acryloyl group, and the “(meth)acryloyl group” refers to an acryloyl group or a methacryloyl group.

[0079] Examples of the (meth)acrylic compound include glycidyl (meth)acrylate, 1,6-hexanediol di(meth)acrylate, 1,9-nonanediol di(meth)acrylate, dicyclopentenyl (meth)acrylate, dicyclopentenyloxyethyl (meth)acrylate, dicyclopentanyl (meth)acrylate, benzyl (meth)acrylate, trimethylolpropane tri(meth)acrylate, 1,12-dodecyl glycol di(meth)acrylate, lauryl (meth)acrylate, and (meth)acrylic acid-modified silicone oil.

[0080] These (meth)acrylic compounds may be used alone or in combination of two or more.

[0081] In addition, in this specification, the said "(meth)acrylate" means acrylate or methacrylate.

[0082] The preferred lower limit of the content of the other curable resin in 100 parts by weight of the curable resin is 5 parts by weight, and the preferred upper limit is 30 parts by weight. By making the content of the other curable resin within this range, the coating properties can be improved without deteriorating the dielectric properties of the photocurable resin composition for electronic devices obtained. The more preferred lower limit of the content of the other curable resin is 10 parts by weight, and the more preferred upper limit is 20 parts by weight.

[0083] The photocurable resin composition for electronic devices of the present invention contains a polymerization initiator.

[0084] As the above-mentioned polymerization initiator, a photocationic polymerization initiator is preferably used. In addition, when the above-mentioned (meth) acrylic resin is contained as the above-mentioned other curable resin, as the above-mentioned polymerization initiator, the above-mentioned photocationic polymerization initiator and the light free radical polymerization initiator can be used in combination. In addition, a thermal cationic polymerization initiator and a thermal free radical polymerization initiator can be used within the scope that does not hinder the purpose of the present invention.

[0085] The photocationic polymerization initiator is not particularly limited as long as it generates a protonic acid or a Lewis acid by light irradiation, and may be an ionic photoacid generating type or a nonionic photoacid generating type.

[0086] Examples of the anion portion of the ionic photoacid generating type photocationic polymerization initiator include BF4 - PF6 - 、SbF6 - 、(BX4) - (wherein X represents a phenyl group substituted with at least two fluorine or trifluoromethyl groups) etc. In addition, the anion part may also include PF m (C n F 2n+1 ) 6-m - (wherein m is an integer from 0 to 5, and n is an integer from 1 to 6), etc.

[0087] Examples of the ionic photoacid generating type photocationic polymerization initiator include aromatic sulfonium salts, aromatic iodonium salts, aromatic diazonium salts, aromatic ammonium salts, and (2,4-cyclopentadien-1-yl)((1-methylethyl)benzene)-Fe salts having the anion moiety.

[0088] Examples of the aromatic sulfonium salt include bis(4-(diphenylsulfonyl)phenyl)sulfide bishexafluorophosphate, bis(4-(diphenylsulfonyl)phenyl)sulfide bishexafluoroantimonate, bis(4-(diphenylsulfonyl)phenyl)sulfide bistetrafluoroborate, bis(4-(diphenylsulfonyl)phenyl)sulfide tetrakis(pentafluorophenyl)borate, diphenyl-4-(phenylthio)phenylsulfonium hexafluorophosphate, diphenyl-4-(phenylthio)phenylsulfonium hexafluoroantimonate, diphenyl-4-(phenylthio)phenylsulfonium tetrafluoroborate, diphenyl-4-(phenylthio)phenylsulfonium tetrakis(pentafluorophenyl)borate, triphenylsulfonium hexafluorophosphate, and triphenylsulfonium. bis(4-(bis(4-(2-hydroxyethoxy))phenylsulfonyl)phenyl)sulfide bishexafluorophosphate, bis(4-(bis(4-(2-hydroxyethoxy))phenylsulfonyl)phenyl)sulfide bishexafluoroantimonate, bis(4-(bis(4-(2-hydroxyethoxy))phenylsulfonyl)phenyl)sulfide bistetrafluoroborate, bis(4-(bis(4-(2-hydroxyethoxy))phenylsulfonyl)phenyl)sulfide tetrakis(pentafluorophenyl)borate, tris(4-(4-acetylphenyl)phenylthio)sulfide tetrakis(pentafluorophenyl)borate, and the like.

[0089] Examples of the aromatic iodonium salt include diphenyliodonium hexafluorophosphate, diphenyliodonium hexafluoroantimonate, diphenyliodonium tetrafluoroborate, diphenyliodonium tetrakis(pentafluorophenyl)borate, bis(dodecylphenyl)iodonium hexafluorophosphate, bis(dodecylphenyl)iodonium hexafluoroantimonate, bis(dodecylphenyl)iodonium tetrafluoroborate, bis(dodecylphenyl)iodonium tetrakis(pentafluorophenyl)borate, 4-methylphenyl-4-(1-methylethyl)phenyliodonium hexafluorophosphate, 4-methylphenyl-4-(1-methylethyl)phenyliodonium hexafluoroantimonate, 4-methylphenyl-4-(1-methylethyl)phenyliodonium tetrakis(pentafluorophenyl)borate, and the like.

[0090] Examples of the aromatic diazonium salt include phenyldiazonium hexafluorophosphate, phenyldiazonium hexafluoroantimonate, phenyldiazonium tetrafluoroborate, and phenyldiazonium tetrakis(pentafluorophenyl)borate.

[0091] Examples of the aromatic ammonium salt include 1-benzyl-2-cyanopyridinium hexafluorophosphate, 1-benzyl-2-cyanopyridinium hexafluoroantimonate, 1-benzyl-2-cyanopyridinium tetrafluoroborate, 1-benzyl-2-cyanopyridinium tetrakis(pentafluorophenyl)borate, 1-(naphthylmethyl)-2-cyanopyridinium hexafluorophosphate, 1-(naphthylmethyl)-2-cyanopyridinium hexafluoroantimonate, 1-(naphthylmethyl)-2-cyanopyridinium tetrakis(pentafluorophenyl)borate, and the like.

[0092] Examples of the above-mentioned (2,4-cyclopentadien-1-yl)((1-methylethyl)benzene)-Fe salt include (2,4-cyclopentadien-1-yl)((1-methylethyl)benzene)-Fe(II) hexafluorophosphate, (2,4-cyclopentadien-1-yl)((1-methylethyl)benzene)-Fe(II) hexafluoroantimonate, (2,4-cyclopentadien-1-yl)((1-methylethyl)benzene)-Fe(II) tetrafluoroborate, and (2,4-cyclopentadien-1-yl)((1-methylethyl)benzene)-Fe(II) tetrakis(pentafluorophenyl)borate.

[0093] Examples of the nonionic photoacid-generating photocationic polymerization initiator include nitrobenzyl esters, sulfonic acid derivatives, phosphoric acid esters, phenolsulfonic acid esters, naphthoquinone diazide, and N-hydroxyimidesulfonic acid esters.

[0094] Examples of commercially available photocationic polymerization initiators include photocationic polymerization initiators manufactured by Midori Chemical Co., Ltd., photocationic polymerization initiators manufactured by Union Carbide Co., Ltd., photocationic polymerization initiators manufactured by ADEKA Co., Ltd., photocationic polymerization initiators manufactured by 3M Co., Ltd., photocationic polymerization initiators manufactured by BASF Co., Ltd., and photocationic polymerization initiators manufactured by Rhodia Co., Ltd.

[0095] As the photocationic polymerization initiator manufactured by Midori Chemical Co., Ltd., for example, DTS-200 etc. can be mentioned.

[0096] As the photocationic polymerization initiator manufactured by the Union Carbide Co., Ltd., for example, UVI6990, UVI6974, etc. may be mentioned.

[0097] As said ADEKA photocationic polymerization initiator, SP-150, SP-170 etc. are mentioned, for example.

[0098] Examples of the photocationic polymerization initiator manufactured by 3M include FC-508 and FC-512.

[0099] As said BASF company's photocationic polymerization initiator, IRGACURE261, IRGACURE290 etc. are mentioned, for example.

[0100] As the photocationic polymerization initiator manufactured by the Rhodia company, for example, PI2074 etc. can be mentioned.

[0101] Examples of the photoradical polymerization initiator include benzophenone compounds, acetophenone compounds, acylphosphine oxide compounds, titanocene compounds, oxime ester compounds, benzoin ether compounds, benzil, and thioxanthone compounds.

[0102] As what is commercially available among the said radical photopolymerization initiator, the radical photopolymerization initiator manufactured by BASF Corporation, the radical photopolymerization initiator manufactured by Tokyo Chemical Industry Co., Ltd., etc. are mentioned, for example.

[0103] Examples of the photoradical polymerization initiator manufactured by BASF include IRGACURE 184, IRGACURE 369, IRGACURE 379, IRGACURE 651, IRGACURE 819, IRGACURE 907, IRGACURE 2959, IRGACURE OXE01, and Lucirin TPO.

[0104] Examples of the photoradical polymerization initiator manufactured by Tokyo Chemical Industry Co., Ltd. include benzoin methyl ether, benzoin ethyl ether, and benzoin isopropyl ether.

[0105] As the thermal cationic polymerization initiator, an anion portion of BF4 - PF6 - 、SbF6 - or (BX4)- (wherein X represents a phenyl group substituted with at least two fluorine or trifluoromethyl groups). Among them, sulfonium salts and ammonium salts are preferred.

[0106] Examples of the sulfonium salt include triphenylsulfonium tetrafluoroborate and triphenylsulfonium hexafluoroantimonate.

[0107] Examples of the phosphonium salt include ethyltriphenylphosphonium hexafluoroantimonate and tetrabutylphosphonium hexafluoroantimonate.

[0108] Examples of the ammonium salt include dimethylphenyl(4-methoxybenzyl)ammonium hexafluorophosphate, dimethylphenyl(4-methoxybenzyl)ammonium hexafluoroantimonate, dimethylphenyl(4-methoxybenzyl)ammonium tetrakis(pentafluorophenyl)borate, dimethylphenyl(4-methylbenzyl)ammonium hexafluorophosphate, dimethylphenyl(4-methylbenzyl)ammonium hexafluoroantimonate, dimethylphenyl(4-methylbenzyl)ammonium hexafluorotetrakis(pentafluorophenyl)borate, methylphenyldibenzylammonium hexafluorophosphate, and methylphenyldibenzylammonium hexafluorophosphate. hexafluoroantimonate, methylphenyldibenzylammonium tetra(pentafluorophenyl)borate, phenyltribenzylammonium tetra(pentafluorophenyl)borate, dimethylphenyl(3,4-dimethylbenzyl)ammonium tetra(pentafluorophenyl)borate, N,N-dimethyl-N-benzylanilinium hexafluoroantimonate, N,N-diethyl-N-benzylanilinium tetrafluoroborate, N,N-dimethyl-N-benzylpyridinium hexafluoroantimonate, N,N-diethyl-N-benzylpyridinium trifluoromethanesulfonic acid, etc.

[0109] As a commercial item among the said thermal cationic polymerization initiators, the thermal cationic polymerization initiator manufactured by Sanshin Chemical Industry Co., Ltd. and the thermal cationic polymerization initiator manufactured by King Industries, Ltd. etc. are mentioned, for example.

[0110] Examples of the thermal cationic polymerization initiator manufactured by Sanshin Chemical Industries, Ltd. include San-Aid SI-60, San-Aid SI-80, San-Aid SI-B3, San-Aid SI-B3A, and San-Aid SI-B4.

[0111] Examples of the thermal cationic polymerization initiator manufactured by King Industries include CXC1612 and CXC1821.

[0112] As said thermal radical polymerization initiator, the thermal radical polymerization initiator containing an azo compound, an organic peroxide, etc. is mentioned, for example.

[0113] Examples of the azo compound include 2,2′-azobis(2,4-dimethylvaleronitrile) and azobisisobutyronitrile.

[0114] Examples of the organic peroxide include benzoyl peroxide, ketone peroxide, peroxyketal, hydrogen peroxide, dialkyl peroxide, peroxyester, diacyl peroxide, and peroxydicarbonate.

[0115] Examples of commercially available products of the thermal radical polymerization initiator include VPE-0201, VPE-0401, VPE-0601, VPS-0501, VPS-1001, and V-501 (all manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.).

[0116] Relative to 100 parts by weight of the curable resin, the preferred lower limit of the content of the above-mentioned polymerization initiator is 0.01 parts by weight, and the preferred upper limit is 10 parts by weight. By making the content of the above-mentioned polymerization initiator more than 0.01 parts by weight, the curability of the obtained photocurable resin composition for electronic devices is more excellent. By making the content of the above-mentioned polymerization initiator less than 10 parts by weight, the curing reaction of the obtained photocurable resin composition for electronic devices will not become too fast, the workability becomes better, and the cured product can be made more uniform. The more preferred lower limit of the content of the above-mentioned polymerization initiator is 0.05 parts by weight, and the more preferred upper limit is 5 parts by weight.

[0117] The photocurable resin composition for electronic devices of the present invention may contain a sensitizer or a sensitizing aid. The sensitizer or sensitizing aid has the function of further improving the polymerization initiation efficiency of the polymerization initiator and further promoting the curing reaction of the photocurable resin composition for electronic devices of the present invention.

[0118] Examples of the sensitizer include thioxanthone compounds, 2,2-dimethoxy-1,2-diphenylethane-1-one, benzophenone, 2,4-dichlorobenzophenone, methyl o-benzoylbenzoate, 4,4′-bis(dimethylamino)benzophenone, and 4-benzoyl-4′-methyldiphenyl sulfide.

[0119] Examples of the thioxanthone-based compound include 2,4-diethylthioxanthone and the like.

[0120] Relative to 100 parts by weight of the curable resin, the preferred lower limit of the content of the sensitizer is 0.01 parts by weight, and the preferred upper limit is 3 parts by weight. By making the content of the sensitizer more than 0.01 parts by weight, the sensitization effect is further exerted. By making the content of the sensitizer less than 3 parts by weight, the absorption will not become too large, and light can be transmitted to the deep part. The more preferred lower limit of the content of the sensitizer is 0.1 parts by weight, and the more preferred upper limit is 1 part by weight.

[0121] The photocurable resin composition for electronic devices of the present invention may contain a thermosetting agent within a range not hindering the purpose of the present invention.

[0122] Examples of the thermosetting agent include hydrazide compounds, imidazole derivatives, acid anhydrides, dicyandiamide, guanidine derivatives, modified aliphatic polyamines, and addition products of various amines and epoxy resins.

[0123] Examples of the hydrazide compound include 1,3-bis(hydrazinocarbonylethyl)-5-isopropylhydantoin, sebacic acid dihydrazide, isophthalic acid dihydrazide, adipic acid dihydrazide, and malonic acid dihydrazide.

[0124] Examples of the imidazole derivatives include 1-cyanoethyl-2-phenylimidazole, N-(2-(2-methyl-1-imidazolyl)ethyl)urea, 2,4-diamino-6-(2'-methylimidazolyl-(1'))-ethyl-s-triazine, N,N'-bis(2-methyl-1-imidazolylethyl)urea, N,N'-(2-methyl-1-imidazolylethyl)-adipic acid diamide, 2-phenyl-4-methyl-5-hydroxymethylimidazole, and 2-phenyl-4,5-dihydroxymethylimidazole.

[0125] Examples of the acid anhydride include tetrahydrophthalic anhydride and ethylene glycol bis(anhydrotrimellitate).

[0126] These thermosetting agents may be used alone or in combination of two or more.

[0127] Examples of commercially available products of the thermosetting agent include a thermosetting agent manufactured by Otsuka Chemical Co., Ltd. and a thermosetting agent manufactured by Ajinomoto Fine-Techno Co., Ltd.

[0128] Examples of the thermosetting agent manufactured by Otsuka Chemical Co., Ltd. include SDH and ADH.

[0129] As the thermosetting agent manufactured by Ajinomoto Fine-Techno Co., Ltd., for example, AJICURE VDH, AJICURE VDH-J, AJICURE UDH, etc. can be mentioned.

[0130] The preferred lower limit of the content of the thermosetting agent is 0.5 parts by weight, and the preferred upper limit is 30 parts by weight relative to 100 parts by weight of the curable resin. By making the content of the thermosetting agent within this range, the obtained photocurable resin composition for electronic devices has better thermosetting properties while maintaining excellent storage stability. The more preferred lower limit of the content of the thermosetting agent is 1 part by weight, and the more preferred upper limit is 15 parts by weight.

[0131] The photocurable resin composition for electronic devices of the present invention may further contain a silane coupling agent. The silane coupling agent has a function of improving the adhesion between the photocurable resin composition for electronic devices of the present invention and a substrate or the like.

[0132] Examples of the silane coupling agent include 3-aminopropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, and 3-isocyanatepropyltrimethoxysilane. These silane compounds may be used alone or in combination of two or more.

[0133] The preferred lower limit of the content of the silane coupling agent is 0.1 parts by weight, and the preferred upper limit is 10 parts by weight relative to 100 parts by weight of the curable resin. By making the content of the silane coupling agent within this range, the oozing out caused by the remaining silane coupling agent is suppressed, and the effect of improving the adhesion of the obtained photocurable resin composition for electronic devices is more excellent. The more preferred lower limit of the content of the silane coupling agent is 0.5 parts by weight, and the more preferred upper limit is 5 parts by weight.

[0134] The photocurable resin composition for electronic devices of the present invention may contain a curing retarder. By containing the curing retarder, the pot life of the obtained photocurable resin composition for electronic devices can be prolonged.

[0135] Examples of the curing retardant include polyether compounds.

[0136] Examples of the polyether compound include polyethylene glycol, polypropylene glycol, polytetramethylene glycol, and crown ether compounds, among which crown ether compounds are preferred.

[0137] The preferred lower limit of the content of the curing retarder is 0.05 parts by weight, and the preferred upper limit is 5.0 parts by weight relative to 100 parts by weight of the curable resin. By making the content of the curing retarder within this range, the generation of outgassing when the obtained photocurable resin composition for electronic devices is cured can be suppressed, and the delay effect can be further exerted. The more preferred lower limit of the content of the curing retarder is 0.1 parts by weight, and the more preferred upper limit is 3.0 parts by weight.

[0138] The photocurable resin composition for electronic devices of the present invention may further contain a surface modifier within a range not hindering the purpose of the present invention. By containing the surface modifier, the photocurable resin composition for electronic devices of the present invention can be provided with flatness of the coating film.

[0139] Examples of the surface modifier include surfactants and leveling agents.

[0140] Examples of the surface modifier include silicone-based, acrylic-based, and fluorine-based surface modifiers.

[0141] Examples of commercially available products of the surface modifier include a surface modifier manufactured by BYK-Chemie Japan Co., Ltd. and a surface modifier manufactured by AGC Seimi Chemical Co., Ltd.

[0142] Examples of the surface modifier manufactured by BYK-Chemie Japan include BYK-340 and BYK-345.

[0143] Examples of the surface modifier manufactured by AGC Seimi Chemical include Surflon S-611.

[0144] The photocurable resin composition for electronic devices of the present invention may contain a compound or an ion exchange resin that reacts with an acid generated in the composition within a range that does not hinder the purpose of the present invention.

[0145] Examples of the compound that reacts with the acid generated in the composition include substances that neutralize with the acid, such as carbonates or hydrogen carbonates of alkali metals or alkaline earth metals, etc. Specifically, for example, calcium carbonate, calcium hydrogen carbonate, sodium carbonate, sodium hydrogen carbonate, etc. are used.

[0146] As the ion exchange resin, any of a cation exchange type, anion exchange type, and a dual ion exchange type can be used, and a cation exchange type or a dual ion exchange type capable of adsorbing chloride ions is particularly preferred.

[0147] Furthermore, the photocurable resin composition for electronic devices of the present invention may contain various known additives such as a reinforcing agent, a softening agent, a plasticizer, a viscosity modifier, an ultraviolet absorber, and an antioxidant, as required.

[0148] Examples of methods for producing the photocurable resin composition for electronic devices of the present invention include a method of mixing a curable resin, a polymerization initiator, and additives such as a silane coupling agent added as needed using a mixer such as a homodispersor, a homomixer, a universal mixer, a planetary mixer, a kneader, or a three-roll mill.

[0149] The upper limit of the dielectric constant of the photocurable resin composition for electronic devices of the present invention measured under the conditions of 25° C. and 100 kHz is 3.5. By making the above dielectric constant 3.5 or less, the photocurable resin composition for electronic devices of the present invention can be suitably used for adhesives for touch panels, adhesives for electronic devices such as solder resists for circuit boards, coating agents for electronic devices, etc. The preferred upper limit of the above dielectric constant is 3.3, and the more preferred upper limit is 3.0.

[0150] In addition, the preferred lower limit of the dielectric constant is not particularly limited, but the actual lower limit is 2.2.

[0151] It should be noted that the above-mentioned "dielectric constant" can be measured using a dielectric constant measuring device.

[0152] The photocurable resin composition for electronic devices of the present invention can be suitably used for coating by an inkjet method.

[0153] The inkjet method may be a non-heating inkjet method or a heating inkjet method.

[0154] It should be noted that in this specification, the above-mentioned "non-heated inkjet method" is a method of performing inkjet coating at a coating head temperature below 28°C, and the above-mentioned "heated inkjet method" is a method of performing inkjet coating at a coating head temperature above 28°C.

[0155] In the above-mentioned heated inkjet method, an inkjet coating head equipped with a heating mechanism is used. When the inkjet coating head is equipped with a heating mechanism, the viscosity and surface tension can be reduced when the photocurable resin composition for electronic devices is discharged.

[0156] Examples of the inkjet coating head equipped with a heating mechanism include KM1024 series manufactured by Konica Minolta Inc. and SG1024 series manufactured by Fujifilm Dimatix Co., Ltd.

[0157] When the photocurable resin composition for electronic components of the present invention is used for coating by the above-mentioned heated inkjet method, the heating temperature of the coating head is preferably in the range of 28° C. to 80° C. By setting the heating temperature of the coating head in this range, the viscosity increase of the photocurable resin composition for electronic components over time is further suppressed, and the discharge stability is more excellent.

[0158] The preferred lower limit of the viscosity of the photocurable resin composition for electronic devices of the present invention at 25° C. is 5 mPa·s, and the preferred upper limit is 50 mPa·s. When the viscosity at 25° C. is within this range, coating by an inkjet method can be performed appropriately.

[0159] The more preferred lower limit of the viscosity at 25°C of the photocurable resin composition for electronic devices of the present invention is 8 mPa·s, and a further preferred lower limit is 10 mPa·s. In addition, the more preferred upper limit of the viscosity at 25°C of the photocurable resin composition for electronic devices of the present invention is 40 mPa·s, and a further preferred upper limit is 30 mPa·s.

[0160] In this specification, the "viscosity" refers to a value measured at 25°C and 100 rpm using an E-type viscometer. Examples of the E-type viscometer include VISCOMETER TV-22 (manufactured by Toki Sangyo Co., Ltd.), and a CP1 type cone plate can be used.

[0161] The preferred lower limit of the surface tension at 25°C of the photocurable resin composition for electronic devices of the present invention is 15 mN / m, and the preferred upper limit is 35 mN / m. By setting the surface tension at 25°C to this range, it is possible to appropriately apply the composition by inkjet method. The more preferred lower limit of the surface tension at 25°C is 20 mN / m, the more preferred upper limit is 30 mN / m, the further preferred lower limit is 22 mN / m, and the further preferred upper limit is 28 mN / m.

[0162] The surface tension is a value measured by a Wilhelmy method using a dynamic wettability tester. Examples of the dynamic wettability tester include WET-6100 (manufactured by RHESCA).

[0163] The photocurable resin composition for electronic devices of the present invention can be irradiated with a wavelength of 300 nm to 400 nm and a power of 300 mJ / cm 2 Above and 3000mJ / cm 2 The following cumulative light amounts are used to appropriately cure the product.

[0164] As the light source used in the above-mentioned light irradiation, for example, low-pressure mercury lamp, medium-pressure mercury lamp, high-pressure mercury lamp, ultra-high-pressure mercury lamp, excimer laser, chemical lamp, black light lamp, microwave excitation mercury lamp, metal halide lamp, sodium lamp, halogen lamp, xenon lamp, LED lamp, fluorescent lamp, sunlight, electron beam irradiation device, etc. can be mentioned. These light sources can be used alone or in combination of two or more.

[0165] These light sources are appropriately selected according to the absorption wavelengths of the photocationic polymerization initiator and the photoradical polymerization initiator.

[0166] Examples of the method for irradiating the photocurable resin composition for electronic devices of the present invention with light include simultaneous irradiation with various light sources, sequential irradiation with time differences, and a combination of simultaneous irradiation and sequential irradiation. Any irradiation method can be used.

[0167] The photocurable resin composition for electronic devices of the present invention is suitable for use as an adhesive for electronic devices such as an adhesive for touch panels and a solder resist for circuit boards, or a coating agent for electronic devices. In addition, the photocurable resin composition for electronic devices of the present invention is also suitable for use as a sealant for display elements such as organic EL display elements.

[0168] Effects of the Invention

[0169] According to the present invention, it is possible to provide a photocurable resin composition for electronic devices which has excellent coating properties and curability and a low dielectric constant. DETAILED DESCRIPTION

[0170] Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited to these Examples.

[0171] (Examples 1 to 19, Comparative Examples 1 to 4)

[0172] According to the mixing ratios described in Tables 1 to 3, the materials were uniformly stirred and mixed at a stirring speed of 3000 rpm using a homodispersor type stirring mixer to prepare photocurable resin compositions for electronic devices of Examples 1 to 19 and Comparative Examples 1 to 4. As the homodispersor type stirring mixer, a homodispersor L type (manufactured by PRIMIX) was used.

[0173] In Tables 1 to 3, "X-22-169" is R in the above formula (3). 67 Methyl, R 68 is a connecting bond, X is a group represented by the above formula (6-2) (R 73 is ethylene), and n is 0 (average value).

[0174] In Tables 1 to 3, "X-22-163" is R in the above formula (3). 67 Methyl, R 68 is a n-propylene group, X is a group represented by the above formula (6-1) (R 73 is oxymethylene) and n is 0 (average value).

[0175] In Tables 1 to 3, "X-40-2678" is R in the above formula (5). 72 The 2 R's 72 is a group (R 73 is ethylene), other R 72 The compound wherein the radical is methyl and k is 4 (average value).

[0176] The obtained photocurable resin composition for electronic components was applied on a PET film at a thickness of 100 μm and irradiated with an LED UV lamp at 3000 mJ / cm 2 The film was cured by ultraviolet rays of 395 nm. As an LED UV lamp, an SQ series (manufactured by Quark Technology) was used. Then, gold electrodes were vacuum-deposited on both sides of the cured film in a relative manner into a circle with a diameter of 2 cm and a thickness of 0.1 μm to prepare a test piece for dielectric constant measurement. For the obtained test piece, the dielectric constant was measured under the conditions of 25°C and 100 MHz using a dielectric constant measuring device. As a dielectric constant measuring device, a 1260 impedance analyzer (manufactured by Solartron) and a 1296 dielectric constant measurement interface (manufactured by Solartron) were used. The results are shown in Tables 1 to 3.

[0177] <Evaluation>

[0178] The photocurable resin compositions for electronic devices obtained in Examples and Comparative Examples were evaluated as follows. The results are shown in Tables 1 to 3.

[0179] (1) Viscosity

[0180] The photocurable resin compositions for electronic devices obtained in Examples and Comparative Examples were measured for viscosity at 25° C. and 100 rpm using an E-type viscometer with a CP1 cone and plate. As the E-type viscometer, VISCOMETER TV-22 (manufactured by Toki Sangyo Co., Ltd.) was used.

[0181] (2) Coating properties

[0182] The following coating test was conducted: using an inkjet printer, the photocurable resin composition for electronic components obtained in the examples and comparative examples was printed in a grid pattern at a 25 μm interval with a droplet amount of 10 picoliters on an alkali-cleaned alkali-free glass. As the inkjet printer, a material printer DMP-2831 (manufactured by Fujifilm Corporation) was used, and as the alkali-free glass, AN100 (manufactured by AGC Corporation) was used.

[0183] The coating properties were evaluated by scoring "○" when the printed area was uniformly printed with no uncoated portion or unevenness, "△" when there was no uncoated portion but streak-like unevenness was observed, and "×" when there was an uncoated portion.

[0184] (3) Curing

[0185] Each of the photocurable resin compositions for electronic devices obtained in the examples and comparative examples was irradiated with a LED UV lamp at 3000 mJ / cm 2The composition before curing and the cured product were subjected to FT-IR analysis using a Fourier transform infrared spectrophotometer. As a Fourier transform infrared spectrophotometer, an iS-5 (manufactured by Nicolay) was used. In the case of epoxy groups, 915 cm -1 The reduction rate of the peak at 980 cm after curing was calculated as the curing rate (reaction rate of the cationically polymerizable group). In the case of an oxetane group, -1 The reduction rate of the peak after curing was calculated as the curing rate (reaction rate of the cationically polymerizable group).

[0186] The curability was evaluated by indicating a curing rate of 90% or more as "○", a curing rate of 70% or more and less than 90% as "△", and a curing rate of less than 70% as "×".

[0187] (4) Reliability of organic EL display elements

[0188] (4-1) Preparation of a substrate having a laminate having an organic light-emitting material layer

[0189] On a glass with a length of 25 mm, a width of 25 mm and a thickness of 0.7 mm The ITO electrode was formed into a film with a thickness of 1000 nm and used as a substrate. The substrate was ultrasonically cleaned with acetone, alkaline aqueous solution, ion exchange water and isopropyl alcohol for 15 minutes respectively, and then cleaned with boiled isopropyl alcohol for 10 minutes, and further pre-treated with a UV-ozone cleaner. As the UV-ozone cleaner, NL-UV253 (manufactured by Japan Laser Electronics Co., Ltd.) was used.

[0190] Next, the pre-treated substrate was fixed to the substrate holder of the vacuum evaporation device, 200 mg of N,N'-di(1-naphthyl)-N,N'-diphenylbenzidine (α-NPD) was added to a bisque-fired crucible, 200 mg of tris(8-hydroxyquinoline)aluminum (Alq3) was added to another bisque-fired crucible, and the vacuum chamber was depressurized to 1×10 -4 Then, the crucible containing α-NPD was heated to make α-NPD evaporate at a rate of Deposited on the substrate to form a film thickness Next, the crucible containing Alq3 is heated to The evaporation speed forms a film thickness Then, the substrate with the hole transport layer and the organic light emitting material layer formed thereon was moved to another vacuum evaporation device having a tungsten resistance heating boat, 200 mg of lithium fluoride was placed in one of the tungsten resistance heating boats in the vacuum evaporation device, and 1.0 g of aluminum wire was placed in the other tungsten resistance heating boat. Then, the pressure in the evaporator of the vacuum evaporation device was reduced to 2×10 -4 Pa, lithium fluoride The deposition rate of the film After that, the aluminum Film forming speed The pressure in the vapor deposition chamber was returned to normal pressure with nitrogen, and the substrate on which the laminated body having the organic light-emitting material layer of 10 mm×10 mm was disposed was taken out.

[0191] (4-2) Coating with Inorganic Material Film A

[0192] A mask having an opening of 13 mm×13 mm was placed on the obtained substrate on which the laminate was arranged, and an inorganic material film A was formed by a plasma CVD method so as to cover the entire laminate.

[0193] The plasma CVD method is carried out under the following conditions: SiH4 gas and nitrogen gas are used as raw material gases, the respective flow rates are set to 10 sccm for SiH4 gas and 200 sccm for nitrogen, the RF power is set to 10 W (frequency 2.45 GHz), the temperature in the chamber is set to 100°C, and the pressure in the chamber is set to 0.9 Torr.

[0194] The thickness of the formed inorganic material film A was about 1 μm.

[0195] (4-3) Formation of resin protective film

[0196] The sealant for each organic EL display element obtained in Examples and Comparative Examples was pattern-coated on the obtained substrate using an inkjet discharge device. As the inkjet discharge device, NanoPrinter 500 (manufactured by Microjet Corporation) was used.

[0197] Then, use LED light to irradiate 3000mJ / cm 2 Ultraviolet rays with a wavelength of 365nm are used to cure the sealant used in the organic EL display element to form a resin protective film.

[0198] (4-4) Coating with Inorganic Material Film B

[0199] After forming the resin protective film, a mask having an opening of 12 mm×12 mm was provided, and an inorganic material film B was formed by plasma CVD so as to cover the entire resin protective film, thereby obtaining an organic EL display element.

[0200] The plasma CVD method is performed under the same conditions as those in the above-mentioned "(4-2) Coating with inorganic material film A".

[0201] The thickness of the formed inorganic material film B was about 1 μm.

[0202] (4-5) Light Emitting State of Organic EL Display Element

[0203] The obtained organic EL display element was exposed to an environment of temperature 85° C. and humidity 85% for 100 hours, and then a voltage of 3 V was applied to visually observe the light emission state of the organic EL display element (presence of dark spots and extinction around pixels).

[0204] The case where there are no black spots, peripheral extinction and uniform light emission is recorded as "○", the case where there are no black spots, peripheral extinction but a slight decrease in brightness is confirmed is recorded as "△", and the case where black spots and peripheral extinction are confirmed is recorded as "×" to evaluate the reliability of the organic EL display element.

[0205] (5) Low outgassing

[0206] For each of the photocurable resin compositions for electronic devices obtained in Examples and Comparative Examples, outgassing generated during heating of the cured product was measured by gas chromatography based on the headspace method described below.

[0207] First, 100 mg of each photocurable resin composition for electronic components was applied to a thickness of 300 μm using an applicator, and then irradiated with 3000 mJ / cm 2 The photocurable resin composition for electronic devices was cured by ultraviolet light of a wavelength of 365 nm. Next, the obtained cured product was placed in a headspace vial, the vial was sealed, and heated at 100° C. for 30 minutes, and the generated gas was measured by the headspace method.

[0208] The case where the generated gas was less than 400 ppm was recorded as "◎", the case where the generated gas was 400 ppm or more and less than 600 ppm was recorded as "○", the case where the generated gas was 600 ppm or more and less than 800 ppm was recorded as "△", and the case where the generated gas was 800 ppm or more was recorded as "×" to evaluate the low outgassing property.

[0209]

Table 1

[0210]

[0211]

Table 2

[0212]

[0213]

Table 3

[0214]

[0215] Industrial Applicability

[0216] According to the present invention, it is possible to provide a photocurable resin composition for electronic devices which has excellent coating properties and curability and a low dielectric constant.

Claims

1. A sealant for an organic EL display element, characterized in that: Contains a curable resin and a polymerization initiator, The curable resin comprises a monofunctional polymerizable compound and a polyfunctional cationic polymerizable compound. The total content of the monofunctional polymerizable compound and the polyfunctional cationic polymerizable compound in 100 parts by weight of the curable resin is 70 parts by weight or more, The monofunctional polymerizable compound is at least one selected from the group consisting of a compound represented by the following formula (1-1), a compound represented by the following formula (1-2), a compound represented by the following formula (1-3), a compound represented by the following formula (1-4), a compound represented by the following formula (1-5), a compound represented by the following formula (1-6), and a compound represented by the following formula (1-7), The polyfunctional cationically polymerizable compound is at least one selected from the group consisting of a compound represented by the following formula (2-1), a compound represented by the following formula (2-2), a compound represented by the following formula (2-3), a compound represented by the following formula (2-4), a compound represented by the following formula (3), a compound represented by the following formula (4), and a compound represented by the following formula (5), The ratio of the monofunctional polymerizable compound to the polyfunctional cationic polymerizable compound, i.e., the weight ratio of monofunctional polymerizable compound: polyfunctional cationic polymerizable compound is 1:9 to 9:1, The organic EL display element sealant has a viscosity at 25° C. of 5 mPa·s or more and 50 mPa·s or less. The organic EL display element sealant has a dielectric constant of 3.5 or less measured under the conditions of 25° C. and 100 kHz. In formula (2-1), R 1 ~R 18 represents a hydrogen atom, a halogen atom, an oxygen atom, a hydrocarbon group optionally having an oxygen atom or a halogen atom, or an alkoxy group optionally having a substituent, and each of them may be the same or different, In formula (2-2), R 19 ~R 30 represents a hydrogen atom, a halogen atom, an oxygen atom, a hydrocarbon group optionally having an oxygen atom or a halogen atom, or an alkoxy group optionally having a substituent, and each of them may be the same or different, In formula (2-3), R 31 ~R 48 represents a hydrogen atom, a halogen atom, an oxygen atom, a hydrocarbon group optionally having an oxygen atom or a halogen atom, or an alkoxy group optionally having a substituent, and each of them may be the same or different, In formula (2-4), R 49 ~R 66 represents a hydrogen atom, a halogen atom, an oxygen atom, a hydrocarbon group optionally having an oxygen atom or a halogen atom, or an alkoxy group optionally having a substituent, and each of them may be the same or different, In formula (3), R 67 Each independently represents an alkyl group having 1 to 10 carbon atoms, R 68 each independently represents a chemical bond or an alkylene group having 1 to 6 carbon atoms, X represents a group containing an epoxy group, a group containing an oxetanyl group, or a group containing a vinyl ether group, and n represents an integer of 0 to 1000, In formula (4), R 69 Each independently represents an alkyl group having 1 to 10 carbon atoms, R 70 represents a chemical bond or an alkylene group having 1 to 6 carbon atoms, R 71 Each independently represents an alkyl group having 1 to 10 carbon atoms, a group containing an epoxy group, a group containing an oxetanyl group, or a group containing a vinyl ether group, X represents a group containing an epoxy group, a group containing an oxetanyl group, or a group containing a vinyl ether group, l represents an integer of 0 to 1000, m represents an integer of 1 to 100, wherein, in R 71 When all are alkyl groups having 1 to 10 carbon atoms, m represents an integer of 2 to 100, In formula (5), R 72 each independently represents an alkyl group having 1 to 10 carbon atoms, a group containing an epoxy group, a group containing an oxetanyl group, or a group containing a vinyl ether group, 2k R 72 At least 2 R 72 represents a group including an epoxy group, a group including an oxetanyl group, or a group including a vinyl ether group, and k represents an integer of 3 or more and 6 or less.

2. The sealing agent for an organic EL display element according to claim 1, wherein The polyfunctional cationically polymerizable compound is at least one selected from the group consisting of the compound represented by the formula (3), the compound represented by the formula (4), and the compound represented by the formula (5).

3. The sealing agent for an organic EL display element according to claim 1 or 2, wherein The ratio of the monofunctional polymerizable compound to the polyfunctional cationically polymerizable compound, that is, the monofunctional polymerizable compound: the polyfunctional cationically polymerizable compound, is 3:7 to 7:3 in terms of weight ratio.

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