Sealant composition

Abstract

To provide a liquid crystal sealant that yields a cured product having a high glass transition temperature (Tg) and low moisture permeability.SOLUTION: The present invention relates to a sealant composition comprising: (A) a curable resin containing one or more selected from the group consisting of (A-1) an epoxy resin having two or more functional groups, (A-2) a partially (meth)acrylated epoxy resin of an epoxy resin having two or more functional groups, and (A-3) a (meth)acrylic resin having two or more functional groups; (B) a photopolymerization initiator and / or (C) a thermal curing agent; and (D) a benzoxazine compound.SELECTED DRAWING: None

Description

Technical Field

[0001] The present invention relates to a sealant composition.

Background Art

[0002] Electronic devices such as organic electroluminescence, electronic paper, solar cells, and liquid crystal display devices are mainly sealed with a resin composition for the purpose of preventing adverse effects caused by moisture.

[0003] As such a resin composition, a sealant containing a curable resin such as an epoxy resin or a partially (meth) acrylated epoxy resin is used to obtain a cured product with low moisture permeability (see, for example, Patent Documents 1 and 2).

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0005] The present inventors have found that there is room for improvement in increasing the glass transition temperature (Tg) and further reducing the moisture permeability of the cured product in the sealants described in Patent Documents 1 and 2.

[0006] Therefore, an object of the present invention is to provide a liquid crystal sealant that gives a cured product having a high Tg and low moisture permeability.

Means for Solving the Problems

[0007] The present invention relates to the following. [1]A curable resin containing at least one selected from the group consisting of (A)(A-1) an epoxy resin having two or more functional groups, (A-2) a partial (meth)acrylated epoxy resin of an epoxy resin having two or more functional groups, and (A-3) a (meth)acrylic resin having two or more functional groups, (B) a photopolymerization initiator and / or (C) a thermosetting agent, and (D) a benzoxazine compound A sealant composition comprising. [2] The sealant composition according to [1], wherein the (D) has two or more benzoxazine rings in the molecule. [3] The sealant composition according to [1] or [2], wherein the (D) is at least one selected from the group consisting of a benzoxazine compound represented by the following general formula (2) and a benzoxazine compound represented by the following general formula (3). [Chemical formula] [In formula (2), R 1 and R 2 are the same or different and are each independently an alkyl group, a cycloalkyl group or an aryl group, X 1 and X 2 are the same or different and are each independently a hydrogen atom, an alkyl group, a cycloalkyl group or an aryl group, Y 1 are the same or different and are each independently -O-, -S-, -SO 2 -, -C(=O)-, an alkylene group, a cycloalkylene group, an arylene group, or A 1 -arylene-A 2 group, where A 1 and A 2 are the same or different and are each independently an alkylene group, a cycloalkylene group, -O-, -S-, -SO 2 - or -C(=O)-, m is 0 or 1, n is an integer from 1 to 10, In formula (2), the alkyl group, cycloalkyl group, aryl group, alkylene group, cycloalkylene group or arylene group is each independently unsubstituted or substituted with a substituent.

Chemical formula

Advantages of the Invention

[0008] The present invention can provide a liquid crystal sealant that gives a cured product having a high Tg and a low moisture permeability.

Modes for Carrying Out the Invention

[0009] Hereinafter, preferred embodiments of the present invention will be described. In this specification, the "(meth)acryloyl group" refers to an acryloyl group (CH 2 =CH 2 -C(=O)-) and at least one of a methacryloyl group (CH 2 =CH(CH 3 )-C(=O)-).

[0010] In this specification, "(B) photoinitiator" may also be referred to as "component (B)". The same applies to "(C) thermosetting agent" and the like.

[0011] [Sealant composition] The sealant composition includes a curable resin containing at least one selected from the group consisting of (A) (A-1) a polyfunctional epoxy resin having two or more functional groups, (A-2) a partially (meth)acrylated epoxy resin of a polyfunctional epoxy resin having two or more functional groups, and (A-3) a (meth)acrylic resin having two or more functional groups, (B) a photoinitiator and / or (C) a thermosetting agent, and (D) a benzoxazine compound.

[0012] The present inventor has found that by applying a benzoxazine-based compound to the sealant composition, properties such as Tg and moisture permeability can be improved.

[0013] In addition to giving a cured product having a high Tg and low moisture permeability, the sealant composition tends to have a high reaction rate of epoxy groups. That is, when only (A-1) a polyfunctional epoxy resin having two or more functional groups and / or (A-2) a partially (meth)acrylated epoxy resin of a polyfunctional epoxy resin having two or more functional groups is included as component (A), the reaction rate of epoxy groups tends to be high.

[0014] <(A) Curable resin> Component (A) is a curable component of the sealant composition. Component (A) includes one or more selected from the group consisting of (A-1) a polyfunctional epoxy resin having two or more functional groups, (A-2) a partially (meth)acrylated epoxy resin of a polyfunctional epoxy resin having two or more functional groups, and (A-3) a (meth)acrylic resin having two or more functional groups. It should be noted that the component corresponding to component (A-2) is not included in component (A-1). And the component corresponding to component (A-2) is not included in component (A-3).

[0015] ≪(A-1) Polyfunctional epoxy resin having two or more functional groups≫ An epoxy resin is a curable resin having an epoxy group. The epoxy functionality of the epoxy resin can be appropriately set according to the desired properties of the sealant composition. The epoxy functionality of the epoxy resin is particularly preferably 2 to 4 functional groups.

[0016] Examples of the polyfunctional epoxy resin having two or more functional groups include bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, phenol novolak type epoxy resin, cresol novolak type epoxy resin, bisphenol A novolak type epoxy resin, bisphenol F novolak type epoxy resin, alicyclic epoxy resin, aliphatic chain epoxy resin, glycidyl ester type epoxy resin, glycidyl amine type epoxy resin, hydantoin type epoxy resin, isocyanurate type epoxy resin, phenol novolak type epoxy resin having a triphenol methane skeleton, etc. In addition, glycidyl ether compounds of polyhydric phenols having two or more functional groups, glycidyl ether compounds of polyhydric alcohols having two or more functional groups and their halides, hydrogenated products, etc. can also be used.

[0017] The epoxy resin may be one component or a combination of two or more components.

[0018] ≪(A-2) Partially (meth)acrylated epoxy resin of a polyfunctional epoxy resin having two or more functional groups≫ The partially (meth)acrylated epoxy resin of a difunctional or higher-functional epoxy resin is a modified resin obtained by modifying a part of the epoxy groups of a difunctional or higher-functional epoxy resin with (meth)acrylic acid or (meth)acrylic anhydride. That is, the partially (meth)acrylated epoxy resin of a difunctional or higher-functional epoxy resin has both epoxy groups and (meth)acryloyl groups in the resin. Here, the difunctional or higher-functional epoxy resin is as described above, including preferred ones.

[0019] The partially (meth)acrylated epoxy resin of a difunctional or higher-functional epoxy resin is preferably a modified resin obtained by modifying a part of the epoxy groups of a difunctional epoxy resin with (meth)acrylic acid or (meth)acrylic anhydride.

[0020] ≪(A-3) Difunctional or Higher-Functional (Meth)Acrylic Resin≫ (Meth)acrylic resin is a curable resin having a (meth)acryloyl group. The functionality of the (meth)acrylic resin can be appropriately set according to the desired properties of the sealant composition. The functionality of the (meth)acrylic resin is preferably 2 to 4.

[0021] Examples of the (meth)acrylic resin having two or more functional groups include esters of aliphatic polyhydric alcohols and (meth)acrylic acid, and esters of alkylene oxide adducts of aliphatic polyhydric alcohols and (meth)acrylic acid. Specific examples of the (meth)acrylic resin having two or more functional groups include ethylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate, 1,3-butylene glycol di(meth)acrylate, 1,4-butylene glycol di(meth)acrylate, neopentyl glycol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, tricyclodecane dimethanol di(meth)acrylate, dimethylol dicyclopentane di(meth)acrylate, EO-modified 1,6-hexanediol di(meth)acrylate, EO-modified bisphenol A di(meth)acrylate, PO-modified bisphenol A di(meth)acrylate, polyester di(meth)acrylate (e.g., ARONIX M-6100, manufactured by Toagosei Co., Ltd.), polyethylene glycol di(meth)acrylate (e.g., 4G, manufactured by Shin-Nakamura Chemical Co., Ltd.), and silicone di(meth)acrylate (e.g., EBECRYL 350, manufactured by Daicel Allnex Co., Ltd.). Here, "EO" means ethylene oxide, and "PO" means propylene oxide.

[0022] Examples of the (meth)acrylic resin having three or more functional groups include one or more resins selected from EO-modified glycerol tri(meth)acrylate (trifunctional), PO-modified glycerol tri(meth)acrylate (trifunctional), pentaerythritol tri(meth)acrylate (trifunctional), dipentaerythritol hexa(meth)acrylate (hexafunctional), and pentaerythritol tetra(meth)acrylate (tetrafunctional).

[0023] Furthermore, examples of the (meth)acrylic resin include modified resins in which all of the epoxy groups of an epoxy resin having two or more functional groups are modified with (meth)acrylic acid and / or (meth)acrylic anhydride. Here, the epoxy resin having two or more functional groups is as described above, including preferred ones.

[0024] <<Other curable resins>> Component (A) can contain other curable resins in addition to components (A-1) to (A-3). Examples of other curable resins include resins having unsaturated groups used as the main component of the sealant composition, resins having neither unsaturated groups nor epoxy groups, monofunctional epoxy resins, and / or monofunctional (meth)acrylic resins.

[0025] Examples of resins having unsaturated groups include diene polymers (e.g., polybutadiene polymers, polyisoprene polymers, etc.).

[0026] Examples of resins having neither unsaturated groups nor epoxy groups include modified epoxy resins in which all of the epoxy groups of epoxy resins are modified with modified compounds having no unsaturated groups, urethane resins formed from hydroxyl group-containing compounds and isocyanate group-containing compounds, etc.

[0027] Component (A) may be one component or a combination of two or more components.

[0028] <(B) Photoinitiator> (B) The photoinitiator is a component that can make the sealant composition a photocurable composition. Examples of photoinitiators include radical polymerization initiators, anionic polymerization initiators, and / or cationic polymerization initiators.

[0029] Examples of the radical polymerization initiator include benzoins, acetophenones, benzophenones, thioxanthones, α-acyloxime esters, phenylglyoxylates, benzyls, azo compounds, diphenyl sulfide compounds, acylphosphine oxide compounds, benzoin ethers, anthraquinones, organic peroxides, etc. The radical polymerization initiator preferably has low solubility in the liquid crystal and has no reactive group that causes the decomposition product to gasify upon light irradiation. Further, as the radical polymerization initiator, a compound obtained by reacting a compound having at least two epoxy groups described in WO2012 / 077720 with dimethylaminobenzoic acid, and a polymerization initiator which is a mixture of a compound obtained by reacting a compound having at least two epoxy groups with hydroxythioxanthone are preferable.

[0030] Examples of the anionic polymerization initiator include imidazoles, amines, phosphines, organic metal salts, metal chlorides, organic peroxides, etc.

[0031] Examples of the cationic polymerization initiator include onium salts, iron arene complexes, titanocene complexes, arylsilanol aluminum complexes, Lewis acid compounds, Bronsted acid compounds, benzylsulfonium salts, thiophenium salts, thianium salts, benzylammonium, pyridinium salts, hydrazinium salts, carboxylic acid esters, sulfonic acid esters, amine imides, sulfone compounds, sulfonic acid esters, sulfonimides, disulfonyldiazomethanes, and amines, etc.

[0032] The photopolymerization initiator can be commercially available or prepared according to a known method. Component (B) may be one kind of component or a combination of two or more kinds of components.

[0033] <(C) Thermal curing agent> (C) The thermosetting agent is a component that can make the sealant composition a thermosetting composition. Examples of the thermosetting agent include amine-based thermosetting agents. Examples of the amine-based thermosetting agent include organic acid dihydrazide compounds, amine adducts (adducts of polyvalent amine compounds and epoxy resins, compounds obtained by adducting imidazole compounds to epoxy resins, etc.), imidazole compounds, derivatives of imidazole compounds, dicyandiamide, and other thermosetting agents. Here, the polyvalent amine compound is a compound having at least two primary amino groups, and examples include diamine compounds having two primary amino groups and triamine compounds having three primary amino groups.

[0034] Examples of the organic acid dihydrazide include VDH (1,3-bis(hydrazinocarboethyl)-5-isopropylhydantoin), ADH (adipic acid dihydrazide), UDH (7,11-octadecadiene-1,18-dicarbohydrazide), and LDH (octadecane-1,18-dicarboxylic acid dihydrazide).

[0035] Examples of commercially available products of adducts of polyvalent amine compounds and epoxy resins include EH-5001P, EH-4370S, EH-5015S, EH-4375S, EH-5030S, EH-5057P, EH-4358S (manufactured by ADEKA CORPORATION), FXR-1020, FXR-1030, and FXR-1081 (manufactured by T&K TOKA CORPORATION).

[0036] Examples of commercially available products of compounds obtained by adducting imidazole compounds to epoxy resins include EH-5011S (manufactured by ADEKA CORPORATION) and FXR-1121 (manufactured by T&K TOKA CORPORATION).

[0037] Examples of other amine adducts include Amicure PN-23, Amicure PN-30, Amicure MY-24, and Amicure MY-H (manufactured by Ajinomoto Fine-Techno Co., Inc.).

[0038] Examples of other thermosetting agents include compounds having a urea structure in the molecule and at least one primary amino group. Examples of other thermosetting agents include those described in WO2014 / 010446 and WO2019 / 107070.

[0039] Component (C) preferably has a granular form from the viewpoint of the storage stability of the liquid crystal sealant. The average particle diameter of component (C) is not particularly limited, but is preferably 0.1 to 20.0 μm, more preferably 0.2 to 10.0 μm, and particularly preferably 0.2 to 5.0 μm. The average particle diameter of component (C) can be measured with a laser diffraction particle size distribution measuring device. Specifically, the average particle diameter is the volume average value D 50 (D 50 is the particle diameter when the cumulative volume reaches 50%, that is, the median diameter) and is the measured value. Component (C) having a granular form can be obtained by pulverizing component (C).

[0040] Component (C) may be one component or a combination of two or more components.

[0041] <(D) Benzoxazine compound> (D) The benzoxazine compound has one or more benzoxazine rings in the molecule. Component (D) is a thermosetting monomer in which ring-opening polymerization proceeds by heat. Further, component (D) is also a component that imparts characteristics such as high heat resistance, high dimensional stability, and low water absorption to the cured product of the sealant composition.

[0042] Component (D) preferably has two or more benzoxazine rings in the molecule. Here, the number (mol) of benzoxazine rings in component (D) is calculated from the benzoxazine equivalent of component (D). When component (D) is a combination of two or more components, the number (mol) of benzoxazine rings is the sum of the ring numbers calculated from the benzoxazine equivalents for the two or more benzoxazine compounds. Here, the benzoxazine equivalent of component (D) refers to the equivalent with respect to one benzoxazine ring (i.e., the structure where Z 1 、Z 2 and Z 3 are hydrogen atoms). From the viewpoints of curability and imparting characteristics to the sealant, the benzoxazine equivalent of component (D) is preferably 135 to 600 g / eq, and particularly preferably 140 to 400 g / eq.

[0043] (D) Benzoxazine compounds include polyfunctional benzoxazine compounds having a structural unit of the following general formula (1).

[0044]

Chemical formula

[0045] 〔In formula (1), Z 1 、Z 2 and Z 3 are the same or different and are each independently a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group or a linking group. Here, when at least one of Z 1 、Z 2 and Z 3 is a linking group, the benzene rings in the benzoxazine ring are linked by the linking group. Here, Z 1 and / or Z 2 is a linking group, the nitrogen atoms in the benzoxazine ring are linked by the linking group. Z 3 is a linking group, the nitrogen atoms in the benzoxazine ring are linked by the linking group. In formula (1), the alkyl group, cycloalkyl group, or aryl group is each independently unsubstituted or substituted by a substituent.

[0046] As used herein, alone or in combination with other terms, an "alkyl group" is a monovalent group that is linear or branched. The number of carbon atoms in the alkyl group is preferably from 1 to 12, more preferably from 1 to 6, and particularly preferably from 1 to 4. Examples of the alkyl group include methyl group, ethyl group, propyl group, i-propyl group, n-butyl group, i-butyl group, sec-butyl group, tert-butyl group, n-pentyl group, n-hexyl group, n-heptyl group, n-octyl group, n-nonyl group, n-decyl group, n-undecyl group, n-dodecyl group, and the like.

[0047] The alkyl group can be unsubstituted or substituted by a substituent. The substituent of the alkyl group is not particularly limited, and examples thereof include an aryl group having 6 to 20 carbon atoms (particularly, a phenyl group), a halogen atom, a hydroxyl group, a mercapto group, a carboxy group, an amino group, and the like.

[0048] As used herein, alone or in combination with other terms, an "alkylene group" is a divalent group that is linear or branched. As used herein, the "alkylene group" is It contains at least one of an alkylene group and an alkylidene group. The number of carbon atoms of the alkylene group is preferably from 1 to 12, more preferably from 1 to 6, and particularly preferably from 1 to 4. Examples of the alkylene group include a methylene group, an ethylene group, an ethylidene group (ethylene-1,1-diyl group), a trimethylene group, a propylene group (propane-1,2-diyl group), a propylidene group (propane-1,1-diyl group), an isopropylidene group (propane-2,2-diyl group), a tetramethylene group, a butylidene group (butane-1,1-diyl group), an isobutylidene group (2-methylpropane-1,1-diyl group), a pentamethylene group, a 2-methylpentane-1,5-diyl group, a hexamethylene group, a heptamethylene group, an octamethylene group, a nonamethylene group, a decamethylene group, an undecamethylene group, a dodecamethylene group, and the like.

[0049] The alkylene group can be unsubstituted or substituted by a substituent. Examples of the substituent of the alkylene group include a halogen atom, an aryl group (particularly, a phenyl group), and the like.

[0050] In this specification, alone or in combination with other terms, an "aryl group" is a monovalent group having a monocyclic or polycyclic aromatic ring. The number of carbon atoms of the aryl group is preferably from 6 to 20. Examples of the aryl group include a phenyl group, a biphenylyl group, a naphthyl group, a terphenylyl group, an anthracenyl group, a fluorenyl group, and the like, and preferably a phenyl group and a biphenylyl group.

[0051] The aryl group can be unsubstituted or substituted by a substituent. Examples of the substituent of the aryl group include an alkyl group, an alkoxy group, an alkylcarbonyl group, an alkylmercapto group, a cycloalkyl group, a halogen atom, a hydroxyl group, a mercapto group, a carboxy group, an amino group, and the like.

[0052] As used herein, alone or in combination with other terms, the "arylene group" is a divalent group having a monocyclic or polycyclic aromatic ring. The number of carbon atoms in the arylene group is preferably 6 to 20. Examples of the arylene group include a phenylene group, a naphthylene group, an anthranylene group, a phenanthranylene group, etc., and a phenylene group is preferred.

[0053] The arylene group can be unsubstituted or substituted by a substituent. Examples of the substituent of the arylene group include an alkyl group, an alkoxy group, an alkylcarbonyl group, an alkylmercapto group, a cycloalkyl group, a halogen atom, etc.

[0054] As used herein, alone or in combination with other terms, the "cycloalkyl group" is a monovalent group having a monocyclic or polycyclic alicyclic group with 3 to 20 carbon atoms. Examples of the cycloalkyl group include a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, a cyclodecyl group, a cyclododecyl group, an adamantyl group, etc.

[0055] The cycloalkyl group can be unsubstituted or substituted by a substituent. Examples of the substituent of the cycloalkyl group include an alkyl group, a halogen atom, a hydroxyl group, a mercapto group, a carboxy group, an amino group, etc.

[0056] Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. The halogen atom as a substituent is preferably a fluorine atom or a chlorine atom, and particularly preferably a fluorine atom.

[0057] Examples of the alkyl moiety in the alkoxy group include the examples of the alkyl group described above. Examples of the alkoxy group include a methoxy group, an ethoxy group, a propoxy group, a butoxy group, an i-butoxy group, a sec-butoxy group, a tert-butoxy group, etc.

[0058] Examples of the alkyl group in the alkylcarbonyl group and the alkylmercapto group include the examples of the alkyl group described above. Examples of the alkylcarbonyl group include an acetyl group, a propanoyl group, a 2-methylpropanoyl group, a butanoyl group, and the like. Examples of the alkylmercapto group include a methylmercapto group, an ethylmercapto group, a propylmercapto group, an i-propylmercapto group, a butylmercapto group, an i-butylmercapto group, a sec-butylmercapto group, a tert-butylmercapto group, and the like.

[0059] Z 1 and / or Z 2 When Z 1 is a linking group, examples of the linking group include Y 3 described below, or a direct bond with the benzene ring of another benzoxazine ring (that is, when m described below is 0). Further, when Z 1 is a linking group, examples of the linking group include L

[0060] Component (D) is preferably at least one selected from the group consisting of a benzoxazine compound represented by the following general formula (2) and a benzoxazine compound represented by the following general formula (3).

[0061] ≪Polyfunctional benzoxazine compound represented by general formula (2)≫ The polyfunctional benzoxazine compound represented by general formula (2) is as follows.

[0062]

Chemical formula

[0063] When m is 1, the polyfunctional benzoxazine compound represented by general formula (2) is a compound in which the benzene rings in two or more benzoxazine rings are bonded via group Y 1 . Also, when m is 0 (i.e., when group Y 1 is absent), the polyfunctional benzoxazine compound represented by general formula (2) is a compound in which the benzene ring in the benzoxazine ring is linked to the benzene ring of another benzoxazine ring by direct bonding. The polyfunctional benzoxazine compound represented by general formula (2) corresponds to a polyfunctional benzoxazine compound having a structural unit represented by general formula (1) in which at least one of Z 1 and Z 2 is a linking group.

[0064] Y 1 In, specific examples of the A 1 -arylene-A 2 group include an alkylene group having 1 to 4 carbon atoms - an arylene group having 6 to 20 carbon atoms - an alkylene group having 1 to 4 carbon atoms, an -O-arylene group having 6 to 20 carbon atoms -O-, an -S-arylene group having 6 to 20 carbon atoms -S-, -SO 2 -arylene having 6 to 20 carbon atoms -SO 2Examples of the - group and -C(=O)- arylene -C(=O)- group having 6 to 20 carbon atoms in the arylene group include A 1 -arylene - A 2 The group may also be a group obtained by removing two hydroxyphenyl groups from bisphenol M or P.

[0065] ≪Preferred embodiments≫ R 1 and R 2 are preferably an unsubstituted alkyl group, an unsubstituted aryl group, an aryl group substituted with an alkyl group, and an alkyl group substituted with one or more selected from the group consisting of a hydroxyl group, a mercapto group, a carboxy group, and an amino group. Y 1 is preferably a methylene group, an ethylidene group (ethylene - 1,1 - diyl group), an isopropylidene group (propane - 2,2 - diyl group), -O-, -S-, -SO 2 -, or -C(=O)-. X 1 and X 2 are preferably hydrogen atoms. m is preferably 1. n is preferably 1.

[0066] Examples of the polyfunctional benzoxazine compound represented by the general formula (2) having such a preferred group include the compound of the formula (1X) described in paragraph 0017 of JP - A - 2022 - 118627.

[0067] ≪Polyfunctional benzoxazine compound represented by the general formula (3)≫ The polyfunctional benzoxazine compound represented by the general formula (3) is as follows.

[0068]

Chemical formula

[0069] 〔In the formula (3), L 1 is an alkylene group, a cycloalkylene group, an arylene group, an arylene - A 3- an arylene group, or arylene-A 4 - arylene-A 5 - is an arylene group, where A 3 , A 4 and A 5 are the same or different and are each independently an alkylene group, a cycloalkylene group, -O-, -S-, -SO 2 - or -C(=O)-, X 3 and X 4 are the same or different and are each independently a hydrogen atom, an alkyl group, a cycloalkyl group or an aryl group, In formula (3), the alkyl group, cycloalkyl group, aryl group, alkylene group, cycloalkylene group or arylene group is each independently unsubstituted or substituted by a substituent.〕

[0070] The polyfunctional benzoxazine compound represented by general formula (3) is a compound in which the nitrogen atoms (N atoms) of two benzoxazine rings are bonded via group L 1 . The polyfunctional benzoxazine compound represented by general formula (3) corresponds to a polyfunctional benzoxazine compound having a structural unit represented by general formula (1) in which Z 3 is a linking group.

[0071] L 1 In, specific examples of the arylene-A 3 - arylene group include an arylene-alkylene-arylene group having 6 to 20 carbon atoms in the arylene, 1 to 4 carbon atoms in the alkylene, and 6 to 20 carbon atoms in the arylene, an arylene-O-arylene group having 6 to 20 carbon atoms in the arylene, an arylene-S-arylene group having 6 to 20 carbon atoms in the arylene, an arylene-SO 2 - arylene group having 6 to 20 carbon atoms in the arylene, and an arylene-C(=O)-arylene group having 6 to 20 carbon atoms in the arylene.

[0072] Here, the arylene-alkylene-arylene group having 6 to 20 carbon atoms in the arylene is the following group: [Chemical formula] (wherein R 11 and R 12 are each independently a hydrogen atom, a methyl group, an ethyl group, a trifluoromethyl group or a phenyl group) is preferred.

[0073] Examples of the said group include the following groups. [Chemical formula]

[0074] L 1 In, arylene-A 4 -arylene-A 5 -arylene group specific examples include arylene with 6 to 20 carbon atoms - alkylene with 1 to 4 carbon atoms - arylene with 6 to 20 carbon atoms - alkylene with 1 to 4 carbon atoms - arylene group with 6 to 20 carbon atoms, arylene with 6 to 20 carbon atoms - O - arylene with 6 to 20 carbon atoms - O - arylene group with 6 to 20 carbon atoms, arylene with 6 to 20 carbon atoms - S - arylene with 6 to 20 carbon atoms - S - arylene group with 6 to 20 carbon atoms, etc. Arylene-A 4 -arylene-A 5 -arylene group may be a group obtained by removing two hydroxy groups from bisphenol M or P.

[0075] <<Preferred embodiment>> L 1 is preferably an unsubstituted arylene group (especially an unsubstituted phenylene group), an unsubstituted alkylene group, or an arylene-A 3 -arylene group. X 3 and X 4 are preferably hydrogen atoms.

[0076] Examples of the polyfunctional benzoxazine compound represented by the general formula (3) having such a preferable group include the compound of the formula (2X) described in paragraph 0021 of JP-A-2022-118627.

[0077] Component (D) is preferably a bisphenol F-aniline (F-a) type benzoxazine, a phenol-diaminodiphenylmethane (P-d) type benzoxazine, 3-[4-[4-(2,4-dihydro-1,3-benzoxazin-3-yl)phenoxy]phenyl]-2,4-dihydro-1,3-benzoxazine, 3-[3-[4-(2H-1,3-benzoxazin-3(4H)-yl)phenoxy]phenyl]-3,4-dihydro-2H-1,3-benzoxazine (hereinafter also referred to as "3,4'-APE-BOZ").

[0078] Commercially available products can also be used as component (D). Examples of commercially available products include 3,4'-APE-BOZ (manufactured by Honshu Chemical Industry Co., Ltd.), bisphenol F-aniline (F-a) type benzoxazine, phenol-diaminodiphenylmethane (P-d) type benzoxazine (all manufactured by Shikoku Kasei Co., Ltd.), JBZ-OP100N (manufactured by JFE Chemical Corporation), and the like.

[0079] Component (D) may be one component or a combination of two or more components. Further, component (D) may contain an oligomer in which a part of the benzoxazine compound is polymerized.

[0080] <Other component (E)> The sealant composition can contain other components (E) according to the purpose, as long as the effects of the present invention are not impaired. Examples of component (E) include fillers, coupling agents, liquid thixotropic agents, polymerization inhibitors, solvents, photosensitizers, fillers, reinforcing materials, colorants, stabilizers, extenders, viscosity modifiers, tackifiers, flame retardants, ultraviolet absorbers, antioxidants, discoloration inhibitors, antibacterial agents, antifungal agents, anti-aging agents, antistatic agents, plasticizers, lubricants, smoothing agents, foaming agents, release agents, and the like. Note that the other components are not the above-described components (A) to (D).

[0081] <<Filler>> The filler is added for the purpose of controlling the viscosity of the sealant composition, improving the strength of the cured product obtained by curing the sealant composition, or improving the adhesion reliability of the sealant composition by suppressing the linear expansibility. Examples of the filler include inorganic fillers and organic fillers.

[0082] Examples of the inorganic filler include calcium carbonate, magnesium carbonate, barium sulfate, magnesium sulfate, aluminum silicate, titania, alumina, zinc oxide, silica, kaolin, talc, glass beads, sericite activated clay, bentonite, aluminum nitride, and silicon nitride. The inorganic filler is preferably silica.

[0083] Examples of the organic filler include acrylic particles, polymethyl methacrylate, polystyrene (polystyrene beads), copolymers obtained by copolymerizing monomers constituting these (i.e., methyl methacrylate or styrene) with other monomers, polyethylene particles, polysiloxane resin particles, polyamide particles, polyester fine particles, polyurethane fine particles, and rubber fine particles (acrylic rubber particles, isoprene rubber particles). The organic filler may be core-shell type particles.

[0084] Note that the filler may or may not contain particles that function as a powder thixotropy-imparting agent. Examples of the inorganic powder thixotropy-imparting agent include fumed silica and the like. Examples of the organic powder thixotropy-imparting agent include amide-based (polyhydroxycarboxylic acid amide-based), castor oil-based, polyethylene oxide-based, polyhydroxycarboxylic acid ester-based powder thixotropy-imparting agents.

[0085] The average particle size of the filler is not particularly limited, but is preferably 0.01 μm to 10 μm, and particularly preferably 1 μm to 5 μm. The average particle size of the filler can be measured with a laser diffraction type particle size distribution measuring device.

[0086] Commercially available products can be used as the filler. Examples of commercially available inorganic fillers include Sea Hostar KE-C50 (manufactured by Nippon Shokubai Co., Ltd.). Examples of commercially available organic fillers include Zeffiac F-351 (manufactured by Aika Kogyo Co., Ltd.).

[0087] The filler may be one component or a combination of two or more components.

[0088] ≪Coupling Agent≫ Examples of the coupling agent include silane-based coupling agents and titanate-based coupling agents. The coupling agent is preferably a silane-based coupling agent.

[0089] Examples of the silane-based coupling agent include 3-aminopropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-isocyanatopropyltrimethoxysilane, and 3-glycidoxypropyltrimethoxysilane.

[0090] Examples of commercially available silane-based coupling agents include KBM-403, KBE-403, KBE-9007N, KBE-1003, KBE-503, KBE-846, X-12-1308ES, KBE-903, X-12-1056ES, and X-12-1200EP (all manufactured by Shin-Etsu Chemical Co., Ltd.).

[0091] Examples of the titanate-based coupling agent include phosphite-type titanate coupling agents, alkylbenzene sulfonic acid-type titanate coupling agents, pyrophosphate-type titanate coupling agents, carboxylic acid-type titanate coupling agents, and amine-based titanate coupling agents.

[0092] Examples of commercially available titanate coupling agents include Plenact 46B, Plenact 55, Plenact 41B, Plenact 9SA, Plenact 38S, Plenact 138S, Plenact 238S, Plenact 338X, Plenact 44, Plenact TTS (all manufactured by Ajinomoto Fine-Techno Co., Inc.), and the like.

[0093] The coupling agent may be one component or a combination of two or more components.

[0094] ≪Antioxidant≫ Examples of antioxidants include phenolic antioxidants such as 2,6-di-t-butyl-4-cresol, n-octadecyl 3-(4'-hydroxy-3',5'-di-t-butylphenyl) propionate, 2,2'-methylenebis(4-methyl-6-t-butylphenol), and tetrakis [methylene-3-(3,5-di-t-butyl-4-hydroxyphenyl) propionate] methane; sulfur antioxidants such as dilauryl thiodipropionate, lauryl stearyl thiodipropionate, and pentaerythritol tetrakis(3-laurylthiopropionate); and phosphorus antioxidants such as tris(nonylphenyl) phosphite and tris(2,4-di-t-butylphenyl) phosphite.

[0095] The antioxidant may be one component or a combination of two or more components.

[0096] ≪Other Component (E)≫ Component (E) other than the above-described components can be appropriately selected from known components used in sealants. Each of the components (E) may be one component or a combination of two or more components.

[0097] <Content of Each Component> The content of component (A) is preferably 45 to 90 parts by mass, particularly preferably 55 to 85 parts by mass, based on 100 parts by mass of the sealant composition. The total content of component (A-1), component (A-2) and component (A-3) is preferably 30 to 100 parts by mass, more preferably 50 to 100 parts by mass, and particularly preferably 70 to 100 parts by mass with respect to 100 parts by mass of component (A). The content of component (B) is preferably 0.1 to 10 parts by mass, and particularly preferably 1 to 5 parts by mass with respect to 100 parts by mass of component (A). The content of component (C) is preferably 5.0 to 50 parts by mass, and particularly preferably 10 to 40 parts by mass with respect to 100 parts by mass of component (A). The content of component (D) is preferably 1.0 to 30 parts by mass, and particularly preferably 5.0 to 20 parts by mass with respect to 100 parts by mass of component (A). In component (E), the content of the filler is preferably 5 to 50 parts by mass, and particularly preferably 10 to 40 parts by mass with respect to 100 parts by mass of component (A). In component (E), the content of the coupling agent is preferably 0.1 to 20 parts by mass, and particularly preferably 0.5 to 5 parts by mass with respect to 100 parts by mass of component (A). In addition to the above, the total content of component (E) is preferably 2 to 50 parts by mass, and particularly preferably 5 to 40 parts by mass with respect to 100 parts by mass of component (A).

[0098] <Method for preparing the sealant composition> The sealant composition can be produced by mixing each component. Here, (C) the thermosetting agent can be provided for the mixing of each component as a solid (powder). (D) The benzoxazine compound may be provided for the mixing of each component after being previously dissolved in (A) the curable resin, or may be provided for the mixing of each component as a solid (powder) like (C) the thermosetting agent.

[0099] <Curing method of the sealant composition> The sealant composition can be cured by irradiating with energy rays such as ultraviolet rays, by applying heat, or by applying heat before, after, or simultaneously with the irradiation of energy rays such as ultraviolet rays. Therefore, the sealant composition can be an energy ray curable resin composition, an energy ray and heat curable resin composition, or a heat curable resin composition.

[0100] <Use> The sealant composition can be used to seal (encapsulate) the liquid crystal which is the object. The sealant composition is preferably used as a liquid crystal sealant, a sealant for displays other than liquid crystals, or a sealant for light control. Examples of the liquid crystal sealant include a liquid crystal sealant for display elements and a liquid crystal sealant for light control, and a liquid crystal sealant for the drop method is preferred. Examples of the sealant for displays other than liquid crystals include a sealant for organic EL and a sealant for micro LED. Examples of the sealant for light control include a sealant for electrochromic (EC).

[0101] Specifically, the sealant composition can be used for liquid crystal displays or liquid crystal display elements including module type displays, three-dimensional displays, head-mounted displays, projection type displays, etc.; light quantity adjustment liquid crystal elements such as light control filters, light control shutters, anti-glare mirrors, spatial light modulators, etc.; focus variable liquid crystal elements such as liquid crystal lenses; and light modulation liquid crystal elements such as light deflectors, optical demultiplexers, phase control, polarization control, holograms, diffraction gratings, wavelength filters, frequency filters, etc.

[0102] As a method for manufacturing a liquid crystal element using a liquid crystal sealant, a step of applying a sealant to one of two transparent substrates with electrodes using a dispenser to form a pattern of the sealant, a step of dropping the liquid crystal over the entire inner surface of the frame of the transparent substrate and immediately bonding the other transparent substrate, and a step of curing by irradiating the seal pattern portion with light such as ultraviolet rays, heating the sealant, or applying heat before, after, or simultaneously with the irradiation of energy rays such as ultraviolet rays to the seal pattern portion are included.

Example

[0103] Next, specific embodiments of the present invention will be described in more detail with reference to examples, but the present invention is not limited to these examples.

[0104] [Components Used] 1. Curable resin (1) Partially methacrylated epoxy resin [Synthesis Example of Partially Methacrylated Epoxy Resin] 320.0 g of bisphenol F type epoxy resin (EXA-830CRP, manufactured by DIC Corporation), 86.1 g of methacrylic acid (manufactured by Tokyo Chemical Industry Co., Ltd.), and 500 mg of triphenylphosphine (manufactured by Tokyo Chemical Industry Co., Ltd.) were mixed and stirred at 100 °C for 6 hours. 397.0 g of a partially methacrylated bisphenol F type epoxy resin, which was a pale yellow transparent viscous substance, was obtained. The partially methacrylated bisphenol F type epoxy resin was used as the partially methacrylated epoxy resin.

[0105] 2. Photoinitiator (1) Photoinitiator 1 26.8 g (0.1 epoxy equivalent) of polyethylene glycol diglycidyl ether (EX-830, manufactured by Nagase ChemteX Corporation), 16.5 g (0.1 mol) of 4-dimethylaminobenzoic acid, 3.71 g (0.02 mol) of benzyltrimethylammonium chloride, and 25 g of MIBK (methyl isobutyl ketone) were placed in a flask and stirred at 110 °C for 24 hours using an oil bath. The reaction mixture was cooled to room temperature (25 °C), dissolved in 50 g of chloroform, and washed 6 times with 100 ml of water. The solvent of the organic phase was distilled off under reduced pressure to obtain 35.3 g of Photoinitiator 1.

[0106] (2) Photoinitiator 2 26.8 g (0.1 epoxy equivalent) of polyethylene glycol diglycidyl ether (EX-830, manufactured by Nagase ChemteX Corporation), 22.83 g (0.1 mol) of 2-hydroxy-9H-thioxanthen-9-one, 3.71 g (0.02 mol) of benzyltrimethylammonium chloride, and 40 g of MIBK were placed in a flask and stirred at 110 °C for 72 hours using an oil bath. The reaction mixture was cooled to room temperature, dissolved in 50 g of chloroform, and washed 6 times with 100 ml of water. The solvent in the organic phase was distilled off under reduced pressure to obtain 36.2 g of the photoinitiator 2.

[0107] 3. Thermosetting agent (1) Polyamine-based compound (EH-5030S, manufactured by ADEKA Corporation)

[0108] 4. Benzoxazine compound (1) 3,4’-APE-BOZ (manufactured by Honshu Chemical Industry Co., Ltd.)

Chemical formula

Chemical formula

Chemical formula

Chemical formula

[0109] 5. Filler (1) Core-shell type acrylic resin filler (Zephiace F-351, manufactured by Aika Industries Co., Ltd.)

[0110] 6. Coupling agent (1) 3-Glycidoxypropyltrimethoxysilane (KBM-403, manufactured by Shin-Etsu Chemical Co., Ltd.)

[0111] [Examples 1 - 8] To 100 g of the partially methacrylated epoxy resin obtained in the synthesis example, 10 g of the benzoxazine compound was added, and the mixture was stirred while heating at 80 - 100 °C to dissolve the benzoxazine compound. After returning to room temperature, a photoinitiator, a thermal curing agent, a filler, and a coupling agent were added in the compounding amounts (parts by mass) shown in the table and mixed. Then, the mixture was sufficiently kneaded with a three-roll mill (C-43 / 4×10, manufactured by Inoue Manufacturing Co., Ltd.) to prepare the curable resin composition of the example.

[0112] [Comparative Examples 1 - 2] Each component shown in the table was mixed in the compounding amounts (parts by mass) shown in the table, and then sufficiently kneaded with a three-roll mill (C-43 / 4×10, manufactured by Inoue Manufacturing Co., Ltd.) to prepare the curable resin compositions of the examples and comparative examples.

[0113] The curable resin compositions of the examples and comparative examples were evaluated by the following tests.

[0114] (1) Moisture permeability The curable resin composition was sandwiched between 100 mm × 100 mm PET (polyethylene terephthalate) films with a thickness of 0.1 mm so that the diameter was 36 mm - 38 mm and the thickness was 0.28 mm - 0.32 mm, and both sides were irradiated with light energy of 1500 mJ / cm 2 each at an ultraviolet irradiation illuminance of 100 mW / cm 2 Then, it was heat-cured in a hot air oven at 120 °C for 1 hour to obtain a sample for moisture permeability measurement. The moisture permeability measurement was carried out in accordance with JIS Z0208:1976, using a constant temperature and humidity chamber at 65 °C / 95%RH, and calculated from the weight change by the moisture permeation cup method.

[0115] (2) Reaction rate The curable resin composition was sandwiched between a 25 mm × 25 mm glass for LCD with a thickness of 0.7 mm on one side and a 25 mm × 25 mm PET film with a thickness of 0.1 mm on the other side so that the thickness of the curable resin composition became 0.05 mm, and irradiated with ultraviolet rays at an irradiance of 100 mW / cm 2 and a light energy of 3000 mJ / cm 2 using an ultraviolet irradiation device (UVX-01224S1, manufactured by USHIO INC.). Thereafter, it was heated in an oven at 120 °C for 1 hour to obtain a sample for measurement.

[0116] The curing rate was measured using FT-IR (SpectrumOne, manufactured by PerkinElmer Japan Co., Ltd.), and the reaction rates (conversion rates) of the (meth)acrylic group and the epoxy group were calculated from the peak areas of the (meth)acrylic group or the epoxy group in the obtained IR spectrum. The reaction rate was calculated based on the decrease in the absorption peak area appearing at 1630 cm -1 (or 945 cm -1 ) of the (meth)acrylic group, or the decrease in the absorption peak area appearing at 915 cm -1 of the epoxy group, with reference to the absorption peak area appearing at 1500 cm -1 of the double bond of the benzene ring.

[0117] (3) Storage Elastic Modulus and Tg The curable resin composition was cast into a mold with a length of 5 cm, a width of 5 mm, and a thickness of 0.5 mm, and irradiated with ultraviolet rays at an irradiance of 100 mW / cm 2 and a light energy of 3000 mJ / cm 2 using an ultraviolet irradiation device (UVX-01224S1, manufactured by USHIO INC.). Thereafter, it was heated in an oven at 120 °C for 1 hour to prepare a cured specimen. The obtained cured specimen was measured with a dynamic viscoelasticity measuring device (DMA, manufactured by Seiko Instruments Inc., DM S6100) in a tensile deformation mode at a frequency of 1.0 Hz while increasing the temperature at a rate of 2 °C / min in the range of 0 °C to 200 °C. The value of the storage elastic modulus at 25 °C was extracted from the obtained results. Also, the peak top temperature in the loss tangent tanδ was defined as Tg.

[0118] (4) Then, strength measurement The curable resin composition was dot-applied onto an ITO substrate (30 mm × 30 mm × 0.5 mm t) sprayed with 6-μm spacers at positions of 15 mm × 3 mm and 15 mm × 21 mm such that the diameter of the curable resin composition after lamination would be in the range of 1.5 to 2.5 mm φ. Thereafter, a substrate of the same type (23 mm × 23 mm × 0.5 mm t) was laminated, and ultraviolet light was irradiated (irradiation device: UVX-01224S1, manufactured by Ushio Inc.) with an integrated light quantity of 3000 mJ / cm 2 to cure it, and then heat curing was performed in a 120°C oven for 1 hour to prepare a cured product test piece. Using an autograph (TG-2kN, manufactured by Minebea Co., Ltd.), the test piece was fixed and the position of 15 mm × 25 mm of the substrate was punched out at a speed of 5 mm / min, and the adhesive strength between the ITO substrates (ITO / ITO) was measured.

[0119] (5) Liquid crystal contamination (calculation of elution amount) The curable resin composition was poured into a mold having a diameter of 5 mm and a thickness of 0.5 mm t, and ultraviolet light was irradiated (irradiation device: UVX-01224S1, manufactured by Ushio Inc.) with an integrated light quantity of 3,000 mJ / cm 2 to cure it, and a photocured product of the curable resin composition was obtained. Approximately 0.1 g of the obtained photocured product was placed in an ampoule bottle, and further, a liquid crystal (MLC-6609, manufactured by Merck) was added in an amount 10 times that of the photocured product. This bottle was placed in a 120°C oven for 1 hour, and then allowed to stand at room temperature until it returned to room temperature (25°C), and then the liquid crystal portion was taken out and filtered through a 0.2-μm filter to obtain a liquid crystal sample for evaluation.

[0120] The elution amount of each compound (curable resin and benzoxazine compound) in the liquid crystal was measured using HPLC (high performance liquid chromatography). As a sample for HPLC measurement, a sample obtained by diluting the liquid crystal sample for evaluation 100-fold with acetonitrile was used. Further, the elution amount was calculated from the peak area value of each compound.

[0121] The results are shown in Tables 1 and 2 below.

[0122]

Table 1

[0123]

Table 2

[0124] From Table 1 and Table 2, the sealant compositions of the examples had lower moisture permeability values and higher Tg than the corresponding comparative examples that did not contain component (D). Also, the sealant compositions of the examples had excellent epoxy group reaction rates compared to the corresponding comparative examples that did not contain component (D). Specifically, when comparing Examples 1 to 4 with Comparative Example 1, the composition of Comparative Example 1 had a higher moisture permeability value than the compositions of Examples 1 to 4, indicating inferior moisture permeability. Also, the composition of Comparative Example 1 had a low Tg. Furthermore, the composition of Comparative Example 1 had an inferior epoxy group reaction rate. The same can be said when comparing Examples 5 to 8 with Comparative Example 2.

[0125] Examples 1 to 4 had a higher content of (C) heat curing agent compared to Examples 5 to 8, and it can be said that the curability of the sealant was further enhanced. Therefore, it can be said that the elution amount of the liquid crystal in Examples 1 to 4 was equal to or smaller than that in Examples 5 to 8. Accordingly, the sealant compositions of the examples had a small elution amount of the liquid crystal in the liquid crystal contamination test, and thus it can be said that they can be used as sealants.

Claims

1. A curable resin containing at least one selected from the group consisting of (A) a polyfunctional epoxy resin having two or more functional groups, (A-1) a partially (meth)acrylated epoxy resin of a polyfunctional epoxy resin having two or more functional groups, and (A-3) a (meth)acrylic resin having two or more functional groups, (B) a photopolymerization initiator and / or (C) a thermosetting agent, and (D) a benzoxazine compound A sealant composition containing the same.

2. The sealant composition according to Claim 1, wherein component (D) has two or more benzoxazine rings in the molecule.

3. The sealant composition according to Claim 1, wherein component (D) is at least one selected from the group consisting of a benzoxazine compound represented by the following general formula (2) and a benzoxazine compound represented by the following general formula (3). 【Chemical 12】 [In formula (2), R １ and R ２ are the same or different and each independently is an alkyl group, a cycloalkyl group or an aryl group, X １ and X ２ are the same or different and each independently is a hydrogen atom, an alkyl group, a cycloalkyl group or an aryl group, Y １ is the same as or different from, and each independently is —O—, —S—, —SO ２ —, —C(═O)—, an alkylene group, a cycloalkylene group, an arylene group, or A １ —arylene—A ２ group, where A １ and A ２ are the same as or different from, and each independently is an alkylene group, a cycloalkylene group, —O—, —S—, —SO ２ — or —C(═O)—, m is 0 or 1, n is an integer from 1 to 10, In formula (2), the alkyl group, cycloalkyl group, aryl group, alkylene group, cycloalkylene group or arylene group is each independently unsubstituted or substituted by a substituent. ] 【Chemical Formula 13】 [In formula (3), L １ is an alkylene group, a cycloalkylene group, an arylene group, an arylene-A ３ -arylene group, or an arylene-A ４ -arylene-A ５ -arylene group, where A ３ , A ４ and A ５ are the same or different and are each independently an alkylene group, a cycloalkylene group, -O-, -S-, -SO ２ -, or -C(=O)-, X ３ and X ４ are the same or different and each independently is a hydrogen atom, an alkyl group, a cycloalkyl group or an aryl group, In formula (3), the alkyl group, cycloalkyl group, aryl group, alkylene group, cycloalkylene group or arylene group is each independently unsubstituted or substituted by a substituent. ]

4. The sealant composition according to Claim 1, further containing at least one selected from the group consisting of a filler and a coupling agent.

5. The sealant composition according to Claim 1, wherein the content of component (D) is 1.0 part by mass or more and 30 parts by mass or less with respect to 100 parts by mass of component (A).

6. The sealant composition according to any one of Claims 1 to 5, which is a liquid crystal sealant.

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