Sealant composition

Abstract

To provide a sealant having superior adhesive strength under high-temperature and high-humidity conditions.SOLUTION: A sealant composition comprises (A) a curable resin, (B) a photopolymerization initiator and / or thermosetting agent, (C) a filler and / or a thixotropy agent (where, the filler excludes the thixotropy agent), and (D) a coupling agent. The (D) coupling agent comprises (D-1) a trimethoxysilane-based coupling agent with an epoxy group and (D-2) a triethoxysilane-based coupling agent with a reactive functional group (excluding a triethoxysilane-based coupling agent with an amino group).SELECTED DRAWING: None

Description

[Technical Field]

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

[0002] In the manufacturing of LCD elements, the dripping method allows for the creation of panels by directly dripping liquid crystal into a closed loop of sealant, vacuum lamination, and then releasing the vacuum. This dripping method offers numerous advantages, including reduced liquid crystal usage and shorter injection time into the panel, making it the mainstream method for manufacturing LCD panels using large substrates today. Methods that include the dripping method involve applying the sealant and liquid crystal, laminating the substrate, then removing the gap and aligning the substrate, and curing the sealant, primarily using ultraviolet light. Additionally, the vacuum lamination method for manufacturing electrochemical cells uses a sealant to seal the electrochemical cell's electrolyte, which has the advantage of allowing electrochemical cells to be manufactured without the need for an electrolyte injection port.

[0003] Patent Document 1 describes a sealant for a liquid crystal dropping method, which is characterized by containing a curable resin, a polymerization initiator and / or a heat curing agent, and a titanate-based coupling agent. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2008-179796 Summary of the Invention [Problem to be solved by the invention]

[0005] The sealant described in Patent Document 1 has a problem in that its adhesive strength significantly decreases under high-temperature and high-humidity conditions. Therefore, an object of the present invention is to provide a sealant that has excellent adhesive strength under high-temperature and high-humidity conditions. [Means for solving the problem]

[0006] The present invention relates to the following [1] to [7]. [1] (A) a curable resin; (B) a photopolymerization initiator and / or a heat curing agent; (C) a filler (excluding thixotropic agents) and / or a thixotropic agent; (D) a coupling agent; A sealant composition comprising: The sealing composition, wherein the (D) coupling agent comprises (D-1) a trimethoxysilane coupling agent having an epoxy group and (D-2) a triethoxysilane coupling agent having a reactive functional group (excluding triethoxysilane coupling agents having an amino group). [2] The sealant composition according to [1], wherein the reactive functional group of component (D-2) is at least one selected from the group consisting of an alkoxy group, an epoxy group, a (meth)acryloyl group, a vinyl group, a mercapto group, and an optionally protected isocyanate group. [3] The sealant composition according to [1] or [2], wherein the content of component (D-2) is 20 parts by mass or more and 120 parts by mass or less per 100 parts by mass of component (D-1). [4] The sealant composition according to [1] or [2], wherein the component (D) further contains (D-3) a titanate-based coupling agent. [5] The sealant composition according to [4], wherein the total content of component (D-2) and component (D-3) is 20 parts by mass or more and 120 parts by mass or less per 100 parts by mass of component (D-1). [6] The sealant composition according to any one of [1] to [5], wherein component (A) comprises at least one selected from the group consisting of (A-1) a partially (meth)acrylated epoxy resin of a difunctional or higher epoxy resin and (A-2) a combination of an epoxy resin and an acrylic resin. [7] The sealant composition according to any one of [1] to [5], which is a sealant for liquid crystals or an electrochemical cell. [Effects of the Invention]

[0007] The present invention can provide a sealant that has excellent adhesive strength under high-temperature and high-humidity conditions. DETAILED DESCRIPTION OF THE INVENTION

[0008] Preferred embodiments of the present invention are described below. In this specification, the term "(meth)acryloyl group" includes at least one of an acryloyl group (CH2=CH2-C(=O)-) and a methacryloyl group (CH2=CH(CH3)-C(=O)-).

[0009] In this specification, "(A) curable resin" may also be referred to as "component (A)." The same applies to "(B) photopolymerization initiator and / or thermosetting agent," etc.

[0010] [Sealant composition] The sealant composition includes (A) a curable resin, (B) a photopolymerization initiator and / or a heat curing agent, (C) a filler (excluding thixotropy-imparting agents) and / or a thixotropy-imparting agent, and (D) a coupling agent, wherein the (D) coupling agent includes (D-1) a trimethoxysilane-based coupling agent having an epoxy group and (D-2) a triethoxysilane-based coupling agent having a reactive functional group (excluding triethoxysilane-based coupling agents having an amino group).

[0011] The sealant composition contains a combination of component (D-1) and component (D-2) as a coupling agent. The present inventors have found that this improves adhesive strength (i.e., moisture resistance) under high-temperature, high-humidity conditions. Here, "high-temperature, high-humidity conditions" preferably refer to conditions of 65°C and 95% RH, and particularly preferably to conditions of 65°C and 95% RH for 88 hours. Furthermore, the "adhesive strength" preferably refers to adhesive strength to an ITO substrate.

[0012] <(A) Curing resin> The (A) curable resin is a curable component of the sealant composition. Component (A) is appropriately selected from cationically polymerizable resins, radically polymerizable resins, and / or anionically polymerizable resins depending on the type of component (B) contained in the sealant composition. Examples of component (A) include resins having unsaturated groups and / or epoxy groups. Here, "unsaturated groups" refers to ethylenically unsaturated groups and / or acetylenically unsaturated groups. Specific examples of component (A) include epoxy resins, (meth)acrylic resins, partially (meth)acrylated epoxy resins of bifunctional or higher epoxy resins, and other curable resins.

[0013] ≪Epoxy resin≫ The epoxy resin is a curable resin having an epoxy group. The epoxy functionality of the epoxy resin can be appropriately set depending on the desired properties of the sealant composition, but is preferably difunctional or more, and particularly preferably difunctional to tetrafunctional.

[0014] Examples of difunctional or higher functional epoxy resins include bisphenol A epoxy resins, bisphenol F epoxy resins, bisphenol S epoxy resins, phenol novolac epoxy resins, cresol novolac epoxy resins, bisphenol A novolac epoxy resins, bisphenol F novolac epoxy resins, alicyclic epoxy resins, aliphatic linear epoxy resins, glycidyl ester epoxy resins, glycidyl amine epoxy resins, hydantoin epoxy resins, isocyanurate epoxy resins, and phenol novolac epoxy resins having a triphenolmethane skeleton. Other examples include glycidyl ethers of difunctional or higher functional phenols, glycidyl ethers of difunctional or higher functional alcohols, and their halides and hydrogenated derivatives. Examples of trifunctional and tetrafunctional epoxy resins include the epoxy resins described in JP 2012-077202 A.

[0015] The di- or higher functional epoxy resin is preferably an epoxy resin having a bisphenol structure, and particularly preferably one or more selected from the group consisting of bisphenol A type epoxy resins and bisphenol F type epoxy resins.

[0016] The epoxy resin may be a single component or a combination of two or more components.

[0017] <(Meth)acrylic resin> The (meth)acrylic resin is a curable resin having a (meth)acryloyl group. The functionality of the (meth)acrylic resin can be appropriately set depending on the desired properties of the sealing composition, but is preferably bifunctional or more, and particularly preferably bifunctional to tetrafunctional.

[0018] Examples of difunctional or higher (meth)acrylic resins 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 bifunctional or higher (meth)acrylic resin 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.) etc. Here, "EO" means ethylene oxide and "PO" means propylene oxide.

[0019] Examples of the tri- or higher functional (meth)acrylic resin 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).

[0020] Further, the (meth)acrylic resin may be a modified resin in which all of the epoxy groups of a bifunctional or higher functional epoxy resin have been modified with (meth)acrylic acid and / or acrylic anhydride. Here, the bifunctional or higher functional epoxy resin, including preferred ones, is as described above.

[0021] The (meth)acrylic resin may be a single component or a combination of two or more components.

[0022] <Partially (meth)acrylated epoxy resins of bifunctional or higher functional epoxy resins> A partially (meth)acrylated epoxy resin of a difunctional or higher functional epoxy resin is a modified resin in which some of the epoxy groups of the difunctional or higher functional epoxy resin are modified with (meth)acrylic acid or (meth)acrylic anhydride. That is, a 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, including preferred ones, is as described above.

[0023] The partially (meth)acrylated epoxy resin of a difunctional or higher functional epoxy resin is preferably a modified resin in which some of the epoxy groups of a difunctional epoxy resin have been modified with (meth)acrylic acid or (meth)acrylic anhydride.

[0024] The partially (meth)acrylated epoxy resin of di- or higher functional epoxy resin may be one kind of component or a combination of two or more kinds of components.

[0025] <Other curable resins> Other curable resins include resins other than epoxy resins, (meth)acrylic resins, and partially (meth)acrylated epoxy resins of difunctional or higher epoxy resins, and include conventional resins having unsaturated groups and / or epoxy groups used as base resins for sealant compositions, and resins having neither unsaturated groups nor epoxy groups.

[0026] Examples of resins having an unsaturated group include diene polymers (for example, polybutadiene polymers, polyisoprene polymers, etc.).

[0027] Examples of resins having neither an unsaturated group nor an epoxy group include modified epoxy resins in which all of the epoxy groups of an epoxy resin have been modified with a modifying compound having no unsaturated groups, and urethane resins formed from a hydroxyl group-containing compound and an isocyanate group-containing compound.

[0028] <Preferred Embodiments of Component (A)> Component (A) preferably contains one or more selected from the group consisting of (A-1) partially (meth)acrylated epoxy resins of difunctional or higher epoxy resins and (A-2) combinations of epoxy resins and (meth)acrylic resins. By including component (A-1) and / or component (A-2), component (A) can have the properties of both an epoxy resin and a (meth)acrylic resin. Component (A) may be a single component or a combination of two or more components. Component (A) excludes component (D). Component (A) is preferably a curable resin that does not contain silicon atoms.

[0029] <(B) Photopolymerization initiator and / or heat curing agent> (B) The photopolymerization initiator and / or the heat curing agent are components that can be appropriately selected depending on the type of curable resin contained in the sealant composition and the desired curing conditions (energy ray curing and / or heat curing). The photopolymerization initiator is a component that can convert the sealant composition into a photopolymerization-curable composition. The heat curing agent is a component that can convert the sealant composition into a heat-curable composition. Therefore, the sealant composition may contain either a photopolymerization initiator or a heat curing agent, or may contain both a photopolymerization initiator and a heat curing agent.

[0030] <Photopolymerization initiator> The photopolymerization initiator may be a radical polymerization initiator, an anionic polymerization initiator, and / or a cationic polymerization initiator.

[0031] Examples of radical polymerization initiators include benzoins, acetophenones, benzophenones, thioxanthones, α-acyloxime esters, phenylglyoxylates, benzils, azo compounds, diphenyl sulfide compounds, acylphosphine oxide compounds, benzoin ethers, anthraquinones, and organic peroxides. Radical polymerization initiators are preferably those that have low solubility in liquid crystals and have reactive groups that do not gasify upon exposure to light. Furthermore, preferred radical polymerization initiators include those described in WO2012 / 077720, which are a mixture of a compound obtained by reacting a compound having at least two epoxy groups with dimethylaminobenzoic acid and a compound obtained by reacting a compound having at least two epoxy groups with hydroxythioxanthone.

[0032] Examples of the anionic polymerization initiator include imidazoles, amines, phosphines, organic metal salts, metal chlorides, and organic peroxides.

[0033] Examples of the cationic polymerization initiator include onium salts, iron allene complexes, titanocene complexes, arylsilanol aluminum complexes, Lewis acid compounds, Bronsted acid compounds, benzylsulfonium salts, thiophenium salts, thioranium salts, benzylammonium, pyridinium salts, hydrazinium salts, carboxylic acid esters, sulfonic acid esters, amine imides, sulfone compounds, sulfonic acid esters, sulfonimides, disulfonyldiazomethanes, and amines.

[0034] The photopolymerization initiator is commercially available or can be prepared according to known methods.

[0035] <Thermal hardener> Examples of the heat curing agent include amine-based heat curing agents, such as organic acid dihydrazide compounds, amine adducts, imidazole and its derivatives, dicyandiamide, aromatic amines, epoxy-modified polyamines, and polyaminoureas. Preferred examples of the heat curing agent include organic acid dihydrazides such as 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); polyamine compounds sold by ADEKA Corporation as ADEKA HARDNER EH-5030S, ADEKA HARDNER EH-5057P, and the like; and amine adducts sold by Ajinomoto Fine-Techno Co., Ltd. as Amicure PN-23, Amicure PN-30, Amicure MY-24, Amicure MY-H, and the like.

[0036] Component (B) may be one component or a combination of two or more components.

[0037] <(C) Filler (excluding thixotropic agents) and / or thixotropic agents> (C) Filler (excluding thixotropy-imparting agents) and / or thixotropy-imparting agents are added for the purposes of controlling the viscosity of the sealant composition, improving the strength of a cured product obtained by curing the sealant composition, improving the adhesive reliability of the sealant composition by suppressing linear expansion, imparting thixotropy to the sealant composition, etc.

[0038] <Fillers (excluding thixotropic agents)> The filler (excluding the thixotropic agent) includes inorganic fillers and organic fillers.

[0039] Examples of inorganic fillers include calcium carbonate, magnesium carbonate, barium sulfate, magnesium sulfate, aluminum silicate, titania, alumina, zinc oxide, silica (excluding fumed silica), kaolin, talc, glass beads, sericite activated clay, bentonite, aluminum nitride, and silicon nitride. The inorganic filler is preferably silica.

[0040] Examples of organic fillers include acrylic particles, polymethyl methacrylate, polystyrene (polystyrene beads), copolymers obtained by copolymerizing the 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 a core-shell type particle.

[0041] 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 particle size distribution analyzer.

[0042] Commercially available fillers can be used. Examples of commercially available inorganic fillers include Seahoster KE-C50 (manufactured by Nippon Shokubai Co., Ltd.). Examples of commercially available organic fillers include Zefiac F-351 (manufactured by Aica Kogyo Co., Ltd.).

[0043] <Thixotropy additive> The thixotropic agent includes a powder thixotropic agent and a liquid thixotropic agent.

[0044] Examples of the powder thixotropy-imparting agent include inorganic and organic powder thixotropy-imparting agents. The powder thixotropy-imparting agent may be dissolved or dispersed in a solvent. Examples of inorganic powder thixotropy-imparting agents include fumed silica. Examples of organic powder thixotropy-imparting agents include amide-based (polyhydroxycarboxylic acid amide-based), castor oil-based, polyethylene oxide-based, and polyhydroxycarboxylic acid ester-based powder thixotropy-imparting agents.

[0045] Commercially available powder thixotropic agents can be used. Commercially available fumed silica products include TG-308F (manufactured by Cabot Japan Co., Ltd.) and RY200 (manufactured by Nippon Aerosil Co., Ltd.). Commercially available powder thixotropic agents other than fumed silica include Disparlon 305, Disparlon 4300, Disparlon 6650, Disparlon 6500, Disparlon 6700, and Disparlon F9050 (manufactured by Kusumoto Chemicals Co., Ltd.).

[0046] Examples of the liquid thixotropic agent include ester-based, amide-based, and polycarboxylic acid-based liquid thixotropic agents.

[0047] Examples of ester-based liquid thixotropic agents include liquid thixotropic agents of phosphate esters and liquid thixotropic agents of fatty acid esters. The phosphate esters are preferably polyether-based phosphate esters. Examples of polyether-based phosphate esters include polyoxyethylene alkyl ether phosphate esters, polyoxyethylene alkylphenyl ether phosphate esters, and higher alcohol phosphate esters.

[0048] Commercially available liquid thixotropic agents include Disparlon 3500, Disparlon 3600N, Disparlon 3900EF (manufactured by Kusumoto Chemical Co., Ltd.), RCM-100 (manufactured by Kyoeisha Chemical Co., Ltd.), BYK-R606, BYK-405, BYK-R605, etc. (manufactured by BYK-Chemie Japan KK).

[0049] The thixotropy-imparting agent is preferably a powder thixotropy-imparting agent, more preferably an inorganic powder thixotropy-imparting agent, and particularly preferably fumed silica. Furthermore, when the sealant composition contains a resin having a (meth)acryloyloxy group (i.e., the (meth)acrylic resin contained in component (A-1) and component (A-2)), the powder thixotropy-imparting agent has high compatibility with the resin having a (meth)acryloyloxy group and is likely to efficiently exhibit the effect of improving the thixotropy of the sealant composition.

[0050] Component (C) may be one component or a combination of two or more components.

[0051] <(D) Coupling Agent> (D) Coupling agents include (D-1) trimethoxysilane-based coupling agents having an epoxy group and (D-2) triethoxysilane-based coupling agents having a reactive functional group (however, triethoxysilane-based coupling agents having an amino group are excluded).

[0052] <(D-1) Trimethoxysilane Coupling Agent Having Epoxy Group> (D-1) Trimethoxysilane coupling agent having an epoxy group is a silane compound having an epoxy group and a trimethoxysilyl group. Here, the epoxy group may be bonded to the silicon atom of the silane compound (i.e., trimethoxysilyl group) as an alkyl group substituted with the epoxy group, or may be bonded directly to the silicon atom of the silane compound. Here, the alkyl group is preferably an alkyl group having 1 to 8 carbon atoms, and particularly preferably an alkyl group having 2 to 4 carbon atoms. In addition, the alkyl group may be interrupted by an oxygen atom (-O-) or a tetrasulfide group (-SSSS-).

[0053] Specific examples of component (D-1) include 3-glycidoxypropyltrimethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, and 8-glycidoxyoctyltrimethoxysilane.

[0054] Commercially available products of component (D-1) include KBM-403 (manufactured by Shin-Etsu Chemical Co., Ltd.). Component (D-1) may be one component or a combination of two or more components.

[0055] <(D-2) Triethoxysilane Coupling Agent Having a Reactive Functional Group> (D-2) Triethoxysilane coupling agent having reactive functional group (excluding triethoxysilane coupling agent having amino group) is a silane compound having triethoxysilyl group and reactive functional group.Here, the reactive functional group may be bonded to the silicon atom of the silane compound (i.e., trimethoxysilyl group) as an alkyl group substituted with the reactive functional group, or may be bonded directly to the silicon atom of the silane compound.Here, the alkyl group is as described above in component (D-1).

[0056] Examples of reactive functional groups include alkoxy groups, epoxy groups, (meth)acryloyl groups, vinyl groups, mercapto groups, and optionally protected isocyanate groups. Examples of alkoxy groups include alkoxy groups having 1 to 4 carbon atoms, such as methoxy groups, ethoxy groups, and propoxy groups. Examples of blocking agents for isocyanate groups that may be protected include dimethylpyrazole.

[0057] When component (D-2) has an alkoxy group as a reactive functional group, the alkoxy group is preferably present as a trialkoxysilyl group. In this case, component (D-2) has a triethoxysilyl group and a trialkoxysilyl group. Component (D-2) may be a component having two triethoxysilyl groups in the molecule, a component having one triethoxysilyl group and one trimethoxysilyl group in the molecule, or a component having two triethoxysilyl groups in the molecule.

[0058] When component (D-2) has an epoxy group as a reactive functional group, the epoxy group is preferably present as a glycidyloxy group. When component (D-2) has a (meth)acryloyl group as a reactive functional group, the (meth)acryloyl group is preferably present as a (meth)acryloyloxy group. When component (D-2) has a vinyl group as a reactive functional group, the vinyl group may exist alone or as an alkyl group substituted with the vinyl group. Examples of the alkyl group substituted with the vinyl group include alkenyl groups having 3 to 10 carbon atoms, such as allyl, 3-butenyl, and 7-octenyl.

[0059] Examples of the component (D-2) include silane compounds having an alkoxy group and a triethoxysilyl group, such as bis(triethoxysilylpropyl)tetrasulfide and triethoxysilylthiopropyltrimethoxysilane; silane compounds having an epoxy group and a triethoxysilyl group, such as 3-glycidoxypropyltriethoxysilane and 8-glycidoxyoctyltriethoxysilane; 3-methacryloxypropyltriethoxysilane, 3-acryloxypropyltriethoxysilane, 8-methacryloxyoctyltriethoxysilane; Examples of the silane compound include a silane compound having a (meth)acryloyl group and a triethoxysilyl group, such as triethoxysilane; a silane compound having a vinyl group and a triethoxysilyl group, such as vinyltriethoxysilane and 7-octenyltriethoxysilane; a silane compound having a mercapto group and a triethoxysilyl group, such as 3-mercaptopropyltriethoxysilane; and a silane compound having an optionally protected isocyanate group and a triethoxysilyl group, such as 3-isocyanatepropyltriethoxysilane.

[0060] Commercially available products of component (D-2) include 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.). Component (D-2) may be one type of component or a combination of two or more types of components. Component (D-2) excludes component (D-1). That is, component (D-2) is not a component having both an epoxy group and a trimethoxysilyl group as reactive functional groups.

[0061] Component (D-2) is not a triethoxysilane coupling agent having an amino group. The amino group includes a primary amino group (-NH2) and a secondary amino group (-NH-). Therefore, examples of the triethoxysilane coupling agent having an amino group include a silane compound having a triethoxysilyl group, a primary or secondary amino group, and an alkoxy group, and a silane compound having a triethoxysilyl group and a ureido group.

[0062] Examples of triethoxysilane coupling agents having an amino group include 3-ureidopropyltriethoxysilane, N-2-(aminoethyl)-3-aminopropyltriethoxysilane, 3-aminopropyltriethoxysilane, 3-triethoxysilyl-N-(1,3-dimethyl-butylidene)propylamine, and 3-ureidopropyltriethoxysilane.

[0063] <<More Coupling Agents>> In addition to components (D-1) and (D-2), component (D) may contain a further coupling agent, such as (D-3) a titanate-based coupling agent or (D-4) a further silane coupling agent.

[0064] (D-3) Titanate coupling agents (D-3) Examples of titanate coupling agents include phosphorous acid type titanate coupling agents, alkylbenzenesulfonic acid type titanate coupling agents, pyrophosphoric acid type titanate coupling agents, carboxylic acid type titanate coupling agents, and amine type titanate coupling agents.

[0065] Examples of phosphorous acid type titanate coupling agents include tetraisopropyl bis(dioctyl phosphite) titanate, tetraoctyl bis(ditridecyl phosphite) titanate, tetra(2,2-diallyloxymethyl-1-butyl)bis(di-tridecyl)phosphite titanate, isopropyl tri(dioctyl phosphate) titanate, tetraisopropyl di(dilauroyl phosphite) titanate, di(dioctyl phosphate)oxyacetate titanate, and di(dioctyl phosphate)ethylene titanate.

[0066] Examples of alkylbenzenesulfonic acid type titanate compounds include isopropyl tris(dodecylbenzenesulfonyl)titanate, isopropyl tris(decylbenzenesulfonyl)titanate, isopropyl tris(undecylbenzenesulfonyl)titanate, isopropyl tris(tridecylbenzenesulfonyl)titanate, and isopropyl tris(tetradecylbenzenesulfonyl)titanate.

[0067] Examples of the pyrophosphate type titanate coupling agent include isopropyl dioctyl pyrophosphate titanate, isopropyl tris(dioctyl pyrophosphate) titanate, bis(dioctyl pyrophosphate)oxyacetate titanate, bis(dioctyl pyrophosphate)ethylene titanate, tris(dioctyl pyrophosphate)ethylene titanate, isopropyl octyl,butyl pyrophosphate titanate, isopropyl di(butyl,methyl pyrophosphate) titanate, di(octyl,butyl pyrophosphate)oxyacetate titanate, and di(butyl,methyl pyrophosphate)ethylene titanate.

[0068] Carboxylic acid type titanate coupling agents include isopropyl tri-n-stearoyl titanate, isopropyl diisostearoyl acrylic titanate, isopropyl trioctanoyl titanate, isopropyl triisostearoyl titanate, dimethacrylethylene titanate, isostearoyl methacrylethylene titanate, isopropyl dimethacrylisostearoyl titanate, isopropyl isostearoyl diacryl titanate, dicumylphenyloxyacetate titanate, isopropyl diisostearoyl cumylphenyl titanate, diisostearoyl ethylene titanate, isopropyl distearoyl methacrylic titanate, isopropyl trimethacrylic titanate, isopropyl triacryl titanate, isopropyl trianthranyl titanate, diisopropyloxyacetate titanate, isostearoyl Examples of the titanium dioxide include trimethylolmethacryloxyacetate titanate, isostearoyl acryloxyacetate titanate, dimethacryloxyacetate titanate, isopropyl tricumylphenyl titanate, dicumylphenolate oxyacetate titanate, diacrylethylene titanate, dianthranylethylene titanate, titanium methylphenoxide, titanium allyl acetoacetate triisopropoxide, titanium bis(triethanolamine) diisopropoxide, titanium di-n-butoxide (bis-2,4-pentanedionate), titanium diisopropoxide bis(tetramethylheptanedionate), titanium diisopropoxide bis(ethyl acetoacetate), titanium methacryloxyethyl acetoacetate triisopropoxide, titanium oxide bis(pentanedionate), and diacryloxyacetate titanate.

[0069] Examples of the amine-based titanate coupling agent include isopropyl tri(N-aminoethylaminoethyl)titanate, isopropyl 4-aminobenzenesulfonyl di(dodecylbenzenesulfonyl)titanate, isopropyl di(4-aminobenzoyl)isostearoyltitanate, isopropyl tri(N,N-dimethylethylamino)titanate, 4-aminobenzenesulfonyl dodecylbenzenesulfonyloxyacetate titanate, 4-aminobenzoyl isostearoyloxyacetate titanate, 4-aminobenzenesulfonyl dodecylbenzenesulfonyl ethylene titanate, and 4-aminobenzoyl isostearoyl ethylene titanate.

[0070] Commercially available titanate coupling agents include PLENACT 46B (tetraoctylbis(ditridecylphosphite)titanate), PLENACT 55 (tetra(2,2-diallyloxymethyl-1-butyl)bis(ditridecyl)phosphite titanate), PLENACT 41B (tetraisopropylbis(dioctylphosphite)titanate), PLENACT 9SA (isopropyltris(dodecylbenzenesulfonyl)titanate), and PLENACT 38S (isopropyltris(dioctylpyrophosphite)titanate). Examples of suitable ethylene glycol monosiloxanes include tris(dioctyl pyrophosphate) titanate), Plainact 138S (bis(dioctyl pyrophosphate) oxyacetate titanate), Plainact 238S (tris(dioctyl pyrophosphate) ethylene titanate), Plainact 338X (isopropyl dioctyl pyrophosphate titanate), Plainact 44 (isopropyl tri(N-aminoethyl) titanate), and Plainact TTS (isopropyl triisostearoyl titanate) (all manufactured by Ajinomoto Fine-Techno Co., Ltd.).

[0071] (D-4) Further silane coupling agents (D-4) As other silane coupling agents, methoxysilane coupling agents other than the trimethoxysilane coupling agents having epoxy groups can be mentioned.Such silane coupling agents can be mentioned trimethoxysilane coupling agents without epoxy groups (but without triethoxysilyl groups); monomethoxysilane coupling agents with reactive functional groups; dimethoxysilane coupling agents with reactive functional groups, etc.

[0072] <Preferred Embodiments of Component (D)> From the viewpoint of achieving superior adhesive strength under high temperature and high humidity conditions, component (D) preferably contains (D-3) a titanate-based coupling agent. Component (D) may be one component or a combination of two or more components.

[0073] <Other ingredients (E)> The sealant composition may contain other components (E) depending on the purpose, as long as the effects of the present invention are not impaired. Examples of components (E) include polymerization inhibitors, solvents, photosensitizers, fillers, reinforcing materials, colorants, stabilizers, extenders, viscosity modifiers, tackifiers, flame retardants, UV absorbers, antioxidants, discoloration inhibitors, antibacterial agents, antifungal agents, antiaging agents, antistatic agents, plasticizers, lubricants, leveling agents, foaming agents, and mold release agents. Note that these other components are not the above-mentioned components (A) to (D).

[0074] Component (E) can be appropriately selected from known components used in sealing agents. Component (E) may be one component or a combination of two or more components.

[0075] <Content of each ingredient> The content of component (A) is preferably 50 to 99 parts by mass, particularly preferably 55 to 90 parts by mass, per 100 parts by mass of the total sealant composition. The total content of component (A-1) and component (A-2) is preferably 70 to 100 parts by mass, more preferably 80 to 100 parts by mass, and particularly preferably 90 to 100 parts by mass, per 100 parts by mass of component (A). In component (B), the content of the photopolymerization initiator is preferably 0.1 to 10 parts by mass, and particularly preferably 1 to 5 parts by mass, per 100 parts by mass of component (A). In component (B), the content of the heat curing agent is preferably 5 to 50 parts by mass, and particularly preferably 10 to 40 parts by mass, per 100 parts by mass of component (A). In component (C), the content of the filler (excluding the thixotropy-imparting agent) is preferably 5 to 50 parts by mass, and particularly preferably 10 to 40 parts by mass, per 100 parts by mass of component (A). In component (C), the content of the thixotropic agent is preferably 0.1 to 10 parts by mass, and particularly preferably 0.5 to 5 parts by mass, per 100 parts by mass of component (A). The content of component (D) is preferably 0.1 to 20 parts by mass, particularly preferably 0.5 to 5 parts by mass, per 100 parts by mass of component (A). The content of component (D-2) is preferably 20 to 120 parts by mass, particularly preferably 30 to 100 parts by mass, per 100 parts by mass of component (D-1). The content of component (D-3) is preferably 20 to 120 parts by mass, particularly preferably 30 to 100 parts by mass, per 100 parts by mass of component (D-1). The total content of component (D-3) and component (D-2) is preferably 20 parts by mass or more and 120 parts by mass or less, and particularly preferably 30 parts by mass or more and 100 parts by mass or less, per 100 parts by mass of component (D-1). In component (D), the total content of components (D-1), (D-2), and (D-3) is preferably 70 to 100 parts by mass, more preferably 80 to 100 parts by mass, and particularly preferably 90 to 100 parts by mass, per 100 parts by mass of component (D). The content of component (E) is preferably 2 to 50 parts by mass, particularly preferably 5 to 40 parts by mass, per 100 parts by mass of the total of components (A), (B), (C), and (D).

[0076] <Method for preparing sealant composition> The sealant composition can be produced by mixing the components.

[0077] <Curing method> The sealant composition can be cured by irradiation with energy rays such as ultraviolet rays and by applying heat, or by applying heat before, after, or simultaneously with irradiation with energy rays such as ultraviolet rays. Thus, the sealant composition is a photo- (energy ray) curable, heat-curable, or energy ray and heat-curable composition.

[0078] <Application> The sealant composition can be used to seal (encapsulate) an object, such as a sealant for liquid crystal displays, various flexible displays such as organic EL displays, or electrochemical cells.

[0079] Examples of the liquid crystal sealant composition include liquid crystal sealants used in liquid crystal displays or liquid crystal display elements including modular displays, three-dimensional displays, head-mounted displays, projection displays, etc.; light intensity adjusting liquid crystal elements such as dimming filters, dimming shutters, anti-glare mirrors, and spatial light modulators; focus variable liquid crystal elements such as liquid crystal lenses; and light modulating liquid crystal elements such as optical deflectors, optical demultiplexers, phase control, polarization control, holograms, diffraction gratings, wavelength filters, and frequency filters.

[0080] Examples of methods for manufacturing a liquid crystal display using a liquid crystal sealant include a step of applying the sealant to one of two transparent substrates with electrodes using a dispenser to form a sealant pattern, a step of dropping liquid crystal onto the entire surface within the frame of the transparent substrate and immediately laminating the other transparent substrate, and a step of curing the sealant by irradiating the seal pattern portion with light such as ultraviolet light, heating the sealant, or applying heat before, after, or simultaneously with irradiating the seal pattern portion with energy rays such as ultraviolet light.

[0081] Examples of the sealant for electrochemical cells include those used in dye-sensitized solar cells, anti-glare mirrors, displays, capacitors, batteries, etc. Examples of a method for producing an electrochemical cell using the sealant for electrochemical cells include the method described in JP 2015-167188 A.

[0082] The sealant composition is preferably a sealant for liquid crystals and electrochemical cells. [Example]

[0083] 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.

[0084] [Ingredients used] 1.Curing resin (1) Partially methacrylated bisphenol A type epoxy resin (see Example 1 of Curable Resin Production)

[0085] 2-1. Photopolymerization initiator (1) Photopolymerization initiator 1 (see Photopolymerization initiator Production Example 1) (2) Photopolymerization initiator 2 (see Photopolymerization initiator Production Example 2) 2-2.Heat curing agent (1) Polyamine compound (EH-5057P, manufactured by ADEKA Corporation) (2) Heat Curing Agent 1 (See Heat Curing Agent Production Example 1)

[0086] 3-1. Fillers (excluding thixotropic agents) (1) Silica filler (Seahoster KE-C50, manufactured by Nippon Shokubai Co., Ltd.) (2) Core-shell type acrylic resin filler (Zefiac F-351, manufactured by Aica Kogyo Co., Ltd.) 3-2. Thixotropic agents (1) Hydrophobic fumed silica (TG-308F, manufactured by Cabot Japan Co., Ltd.)

[0087] 4-1. Trimethoxysilane coupling agent with epoxy group (1) 3-glycidoxypropyltrimethoxysilane (KBM-403, manufactured by Shin-Etsu Chemical Co., Ltd.) 4-2. Triethoxysilane coupling agents with reactive functional groups (1) 3-glycidoxypropyltriethoxysilane (KBE-403, manufactured by Shin-Etsu Chemical Co., Ltd.) (2) 3-Isocyanatepropyltriethoxysilane (KBE-9007N, manufactured by Shin-Etsu Chemical Co., Ltd.) (3) Vinyltriethoxysilane (KBE-1003, manufactured by Shin-Etsu Chemical Co., Ltd.) (4) 3-methacryloxypropyltriethoxysilane (KBE-503, manufactured by Shin-Etsu Chemical Co., Ltd.) (5) Bis(triethoxysilylpropyl)tetrasulfide (KBE-846, manufactured by Shin-Etsu Chemical Co., Ltd.) (6) Isocyanate group-blocked triethoxysilane (X-12-1308ES, manufactured by Shin-Etsu Chemical Co., Ltd.; becomes 3-isocyanatepropyltriethoxysilane when a deblocking agent is used.) (7) 3-aminopropyltriethoxysilane (KBE-903, manufactured by Shin-Etsu Chemical Co., Ltd.) (8) Triethoxysilylthiopropyltrimethoxysilane (X-12-1056ES, manufactured by Shin-Etsu Chemical Co., Ltd.) 4-3.Titanate coupling agents (1) Tetraoctylbis(ditridecylphosphite) titanate (Plenact 46B, manufactured by Ajinomoto Fine-Techno Co., Ltd.) (2) Tetra(2,2-diallyloxymethyl-1-butyl)bis(ditridecyl)phosphite titanate (Plenact 55, manufactured by Ajinomoto Fine-Techno Co., Ltd.) (3) Isopropyl tris(dodecylbenzenesulfonyl) titanate (Plenact 9SA, manufactured by Ajinomoto Fine-Techno Co., Ltd.) (4) Isopropyl tris(dioctyl pyrophosphate) titanate (Plenact 38S, manufactured by Ajinomoto Fine-Techno Co., Ltd.) 4-4. Methoxysilane coupling agents other than trimethoxysilane coupling agents having epoxy groups (1) 3-glycidoxypropylmethyldimethoxysilane (KBM-402, manufactured by Shin-Etsu Chemical Co., Ltd.) (2) Tris-(trimethoxysilylpropyl) isocyanurate (KBM-9659, manufactured by Shin-Etsu Chemical Co., Ltd.) (3) 3-(phenylamino)propyltrimethoxysilane (KBM-573, manufactured by Shin-Etsu Chemical Co., Ltd.) (4) Thiourethane-type methoxysilane (X-12-1015M, manufactured by Shin-Etsu Chemical Co., Ltd.)

[0088] [Curable Resin Production Example 1] Partially methacrylated bisphenol A epoxy resin 340.0 g of bisphenol A type epoxy resin (EXA-850CRP, 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, yielding 418.0 g of a pale yellow, transparent, viscous partially methacrylated bisphenol A type epoxy resin.

[0089] [Photopolymerization initiator production example 1] Photopolymerization initiator 1 14.5 g (0.1 epoxy equivalent) of diethylene glycol diglycidyl ether (Denacol EX-850L, Nagase ChemteX Corporation), 16.5 g (1.0 equivalent) of 4-dimethylaminobenzoic acid, 3.71 g (0.2 equivalent) of benzyltrimethylammonium chloride, and 50 g of MIBK (methyl isobutyl ketone) were placed in a flask and stirred at 110°C for 24 hours. The reaction mixture was cooled to room temperature (25°C, the same applies below), dissolved in 50 g of chloroform, and washed six times with 100 ml of water. The solvent in the organic phase was evaporated under reduced pressure, yielding 23.3 g of Photopolymerization Initiator 1.

[0090] [Photopolymerization initiator production example 2] Photopolymerization initiator 2 14.5 g (0.1 epoxy equivalents) of diethylene glycol diglycidyl ether (Denacol EX-850L, Nagase ChemteX Corporation), 22.8 g (1.0 equivalents) of 2-hydroxy-9H-thioxanthen-9-one, 3.71 g (0.2 equivalents) of benzyltrimethylammonium chloride, and 50 g of MIBK were placed in a flask and stirred at 110°C for 24 hours. The reaction mixture was cooled to room temperature, dissolved in 50 g of chloroform, and washed six times with 100 ml of water. The solvent in the organic phase was distilled off under reduced pressure, yielding 27.8 g of photopolymerization initiator 2.

[0091] [Thermal Curing Agent Production Example 1] Thermal Curing Agent 1 500 parts by mass of sebacic acid dihydrazide (SDH, manufactured by Otsuka Chemical Co., Ltd.), 500 parts by mass of dodecanedioic acid dihydrazide (DDH, manufactured by Otsuka Chemical Co., Ltd.), and 50 parts by mass of aluminum oxide (AEROXIDE AluC, manufactured by Nippon Aerosil Co., Ltd.) (aluminum content 2.5% by mass) were placed in a 5000 ml separable flask and heated to 200°C to obtain a mixture in which the two crystalline hydrazide compounds were dissolved to a nearly liquid state. This mixture was then subjected to isothermal treatment at 200°C for 2 hours. The mixture was then transferred to a Pyrex (registered trademark) glass tray preheated to 200°C and placed in a 200°C oven. The molten mixture was then cooled to room temperature in the oven at a cooling rate of approximately 1.0°C / min to obtain a solidified product. The solidified product, once completely cooled to room temperature, was coarsely pulverized using a cutter mill (manufactured by Orient Crusher Co., Ltd.) and finally pulverized using a high-pressure pulverizer (trade name: Nano Jetmizer, manufactured by Aisin Nano Technologies Co., Ltd.) to produce a hydrazide compound (mixed crystals of two types of hydrazide compounds) with an average particle size (median size) of 2.5 μm. This hydrazide compound was designated as thermosetting agent 1.

[0092] [Examples 1 to 14 and Comparative Examples 1 to 7] The components shown in Tables 1 to 3 were mixed in the amounts (parts by mass) shown in Tables 1 to 3, and then thoroughly kneaded using a three-roll mill (C-4 3 / 4 x 10, manufactured by Inoue Seisakusho Co., Ltd.) to prepare sealing agent compositions for the examples and comparative examples.

[0093] The sealing compositions of the examples and comparative examples were evaluated by the following tests.

[0094] (1) Adhesive strength (moisture resistance) The sealant composition was spot-applied at 15 mm x 3 mm and 15 mm x 21 mm positions on an ITO substrate (30 mm x 30 mm x 0.5 mm) on which 6 μm spacers had been scattered, so that the diameter of the curable resin composition after lamination would be in the range of 1.5 to 2.5 mm. Then, a substrate of the same type (23 mm x 23 mm x 0.5 mm) was laminated, and ultraviolet light was applied at an integrated light dose of 3000 mJ / cm. 2 The adhesive was cured by irradiation with UV light (irradiation device: UVX-01224S1, manufactured by Ushio Inc.) and then thermally cured in a 120°C oven for 1 hour to prepare a test specimen of the cured product. The test specimen was placed in a constant temperature and humidity chamber at 65°C / 95%RH for 88 hours, and after removal, a tension and compression testing machine (TG-2kN, manufactured by Minebea Co., Ltd.) was used to measure the adhesive strength between the ITO substrates (ITO / ITO) by pressing the test specimen fixed at a position 15 mm x 25 mm on the substrate at a speed of 5 mm / min.

[0095] (2) Seal pass test The sealant composition was dispensed onto an ITO glass substrate (0.7 mm thick) with an alignment film (SE-5662, manufactured by Nissan Chemical Industries, Ltd.) in a 25 mm x 25 mm frame-shaped pattern using a seal dispenser. Liquid crystal (MLC-6609, manufactured by Merck Ltd.) was then dropped onto the substrate using the liquid crystal dropping method, and the upper and lower substrates were bonded together. After 3 minutes, ultraviolet light (UV irradiation device: UVX-01224S1, manufactured by Ushio Inc., cumulative light intensity: 3,000 mJ / cm) was applied. 2 ) to photocure the film, and then heat-cure it for 60 minutes in a hot air oven at 120°C to prepare a test cell. The liquid crystal test cells prepared were rated as × if they had a seal path, and ◯ if they did not have a seal path.

[0096] The results are shown in Tables 1 to 3 below.

[0097] [Table 1]

[0098] [Table 2]

[0099] [Table 3]

[0100] As can be seen from Tables 1 and 2, the sealant compositions of the examples had excellent adhesive strength under high-temperature and high-humidity conditions. Furthermore, the sealant compositions of the examples showed no seal pass in the seal pass test, and therefore can be used as sealants. A comparison of Examples 1 to 7 showed that when the reactive functional group of component (D-2) was an alkoxy group, the adhesive strength was superior under high temperature and high humidity conditions. A comparison of Examples 7 and 8 showed that when the total content of component (D-2) and component (D-3) was low relative to 100 parts by mass of component (D-1), the adhesive strength was superior under high-temperature and high-humidity conditions. A comparison of Example 7 with Examples 9 to 11 (a comparison of Example 1 with Examples 12 to 14) showed that when component (D) further contained component (D-3), the adhesive strength under high-temperature and high-humidity conditions was superior.

[0101] On the other hand, the composition of Comparative Example 1 does not contain component (D). The composition of Comparative Example 2 contains methyldimethoxysilane having an epoxy group. The composition of Comparative Example 3 contains trimethoxysilane having an isocyanurate moiety. The compositions of Comparative Examples 4 and 5 contain trimethoxysilane having a secondary amino group. The composition of Comparative Example 6 contains component (D-1) and component (D-3). As can be seen from Table 3, the compositions of Comparative Examples 1 to 6 had poor adhesive strength under high-temperature and high-humidity conditions.

Claims

1. (A) a curable resin; (B) a photopolymerization initiator and / or a heat curing agent; (C) a filler (excluding thixotropic agents) and / or a thixotropic agent; (D) a coupling agent; A sealant composition comprising: the sealant composition is a sealant for liquid crystals or electrochemical cells, the component (A) is at least one selected from the group consisting of (A-1) a partially (meth)acrylated epoxy resin of a difunctional or higher functional epoxy resin and (A-2) a combination of an epoxy resin and an acrylic resin; The component (D) includes (D-1) a trimethoxysilane coupling agent having an epoxy group, (D-2) a triethoxysilane coupling agent having a reactive functional group (excluding triethoxysilane coupling agents having an amino group), and (D-3) a titanate coupling agent; the component (D-1) is at least one selected from the group consisting of 3-glycidoxypropyltrimethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, and 8-glycidoxyoctyltrimethoxysilane; The reactive functional group of the component (D-2) is at least one selected from the group consisting of an alkoxy group, an epoxy group, a (meth)acryloyl group, a vinyl group, a mercapto group, and an optionally protected isocyanate group. Sealant composition.

2. 2. The sealant composition according to claim 1, wherein the content of component (D-2) is 20 parts by mass or more and 120 parts by mass or less per 100 parts by mass of component (D-1).

3. 2. The sealant composition according to claim 1, wherein the total content of component (D-2) and component (D-3) is 20 parts by mass or more and 120 parts by mass or less per 100 parts by mass of component (D-1).

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