Curable composition, cured product, adhesive, and sealant

Abstract

Provided are: a curable composition that has, at high standards, curability, mechanical strength, and low viscosity; a cured product of the same; an adhesive; and a sealant. The curable composition contains an epoxy-oxetane compound represented by chemical formula (I). In the formula, the Rs are the same or different, and each represents a hydrogen atom or a C1-3 alkyl group.

Description

Curable composition, cured product, adhesive and sealant

[0001] The present invention relates to a curable composition, a cured product, an adhesive, and a sealant.

[0002] Epoxy oxetane compounds have attracted attention in recent years as photo- and thermo-curable monomers, and curable compositions containing them as components exhibit little shrinkage upon curing, and the resulting cured products (resins) are excellent in toughness, mechanical properties (mechanical strength), heat resistance, electrical properties, water resistance (moisture resistance), weather resistance, transparency, adhesion to other materials, etc. Because of these excellent characteristics, curable compositions containing epoxy oxetane compounds are increasingly being used as raw materials for coating materials, paints, inks, adhesive materials (adhesives), pressure-sensitive adhesive materials, films, pastes, optical materials, sealing materials (sealants), resist materials, etc.

[0003] Prior art related to the present invention will be described below with reference to related literature. The invention described in Patent Document 1 relates to an actinic ray-curable ink composition containing a polymerizable compound having a molecular weight of 600 or less and containing three or more cationically polymerizable groups in the molecule. This document describes, as polymerizable compounds, an epoxy compound represented by chemical formula (Ref-1) and an epoxy-oxetane compound represented by chemical formula (Ref-2).

[0004]

[0005]

[0006] The invention described in Patent Document 2 relates to a thin film adhesive composition containing a cyclic ether compound having an epoxy group and an oxetanyl group. This document describes an epoxy-oxetane compound represented by the chemical formula (Ref-3) as an example of a cyclic ether compound having an epoxy group and an oxetanyl group.

[0007]

[0008] Curable compositions containing epoxy-oxetane compounds used in various applications are required to have the following properties: they can be cured to produce a cured product; and they are also required to have low viscosity from the viewpoint of workability during preparation and use of the curable compositions. Furthermore, the cured products obtained by curing the curable compositions are required to have the following properties: high elasticity and excellent rigidity, high flexural strength, and excellent mechanical strength due to the formation of a uniform three-dimensional network with few structural defects in the cured product. Curable compositions containing epoxy-oxetane compounds represented by chemical formulas (Ref-1) to (Ref-3) and their cured products have not combined these properties at a high level, and have had problems with curability, viscosity, and / or mechanical strength.

[0009] Japanese Patent Publication No. 2010-111713 Japanese Patent Publication No. 2019-189789

[0010] An object of one aspect of the present invention is to provide a curable composition that combines high levels of curability, low viscosity, and mechanical strength, as well as a cured product thereof, an adhesive, and a sealant.

[0011] One aspect of the present invention is a curable composition containing an epoxy oxetane compound represented by formula (I).

[0012] (In the formula, R may be the same or different and represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms.)

[0013] A curable composition containing an epoxy-oxetane compound represented by chemical formula (I) can be a curable composition having excellent curability, low viscosity, and excellent workability. Furthermore, the cured product obtained by curing the curable composition has high elasticity, excellent rigidity, and high bending strength, and has excellent mechanical strength due to the formation of a uniform three-dimensional network with few structural defects in the cured product.

[0014] 1 is an IR spectrum chart of a pale yellow, transparent liquid obtained in Synthesis Example 3. FIG. 2 is an IR spectrum chart of a colorless, transparent liquid obtained in Synthesis Example 4. FIG. 3 is an IR spectrum chart of a pale yellow, transparent liquid obtained in Synthesis Example 7. FIG. 4 is an IR spectrum chart of a colorless, transparent liquid obtained in Synthesis Example 10. FIG. 5 is an IR spectrum chart of a pale yellow, transparent liquid obtained in Synthesis Example 12.

[0015] A curable compound according to one embodiment of the present invention contains an epoxy-oxetane compound represented by chemical formula (I). The epoxy-oxetane compound represented by chemical formula (I) has a structure in which two epoxy groups are symmetrically arranged with respect to one oxetane ring having an ethyl group, and the oxetane ring and the two epoxy groups are bonded via a connector each having an ether bond.

[0016]

[0017] In the above chemical formula (I), R may be the same or different and represent a hydrogen atom or an alkyl group having 1 to 3 carbon atoms. The alkyl group may be linear or branched. Specific examples include a methyl group, an ethyl group, an n-propyl group, and an isopropyl group. From the standpoint of easy availability of raw materials and simplification of the synthesis process, it is preferable that R are the same and represent a hydrogen atom or a methyl group.

[0018] Examples of the epoxy oxetane compound represented by chemical formula (I) include compounds represented by chemical formulas (I-1) to (I-6).

[0019]

[0020] From the viewpoints of easy availability of raw materials and simplification of the synthesis process, the epoxy oxetane compound represented by chemical formula (I) is preferably an epoxy oxetane compound represented by chemical formulas (I-1) to (I-6), and more preferably an epoxy oxetane compound represented by chemical formula (I-1). The epoxy oxetane compound represented by chemical formula (I) may be used alone or in combination of two or more types.

[0021] <Method for synthesizing the epoxy-oxetane compound represented by chemical formula (I)> A bifunctional olefin compound having a hydroxy group represented by chemical formula (II) is reacted with an oxetane compound having a leaving group represented by chemical formula (III) to produce an olefin-oxetane compound represented by chemical formula (Ia), and then the double bond of this compound is epoxidized, thereby synthesizing the epoxy-oxetane compound represented by chemical formula (I) (see reaction scheme (A)).

[0022]

[0023] In chemical formula (III), X is a leaving group and represents a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, a mesyloxy group (OMs), a tosyloxy group (OTs), or a trifluoromethanesulfonyloxy group (OTf). In chemical formulas (II) and (Ia), R has the same meaning as R in chemical formula (I), and the wavy line represents a trans isomer, a cis isomer, or a mixture thereof.

[0024] Examples of the oxetane compound having a leaving group represented by the above chemical formula (III) include 3-ethyl-3-methanesulfonyloxymethyloxetane, 3-bromomethyl-3-ethyloxetane, and the like.

[0025] Examples of the bifunctional olefin compound having a hydroxy group represented by the chemical formula (II) include compounds represented by the chemical formulas (II-1) to (II-15). The bifunctional olefin compounds may be used alone or in combination of two kinds.

[0026]

[0027] The bifunctional olefin compound having a hydroxy group represented by the chemical formula (II) can be synthesized, for example, by the method described in Chinese Patent Publication No. 102267878. Biomass-derived raw materials can also be used to synthesize the bifunctional olefin compound, and from the viewpoint of reducing the environmental load, it is preferable to use the bifunctional olefin compound synthesized from biomass-derived raw materials. Specifically, the biomass-derived bifunctional olefin compound can be synthesized by using biomass-derived 2-chloromethyloxirane (epichlorohydrin) and a biomass-derived olefin compound having a terminal hydroxy group as raw materials.

[0028] The oxetane compound having a leaving group represented by chemical formula (III) can be synthesized, for example, by the method described in JP 2007-332294 A. Biomass-derived raw materials can also be used to synthesize the oxetane compound, and from the viewpoint of reducing the environmental burden, it is preferable to use the oxetane compound synthesized from biomass-derived raw materials. By using a biomass-derived bifunctional olefin compound having a hydroxy group represented by chemical formula (II) and / or a biomass-derived oxetane compound having a leaving group represented by chemical formula (III) as raw materials, a biomass-derived epoxy-oxetane compound represented by chemical formula (I) can be synthesized.

[0029] The amount (charge amount) of the bifunctional olefin compound having a hydroxy group represented by the chemical formula (II) is preferably an appropriate ratio in the range of 0.8 to 2 times the molar amount of the oxetane compound having a leaving group represented by the chemical formula (III).

[0030] In addition, when the bifunctional olefin compound represented by the chemical formula (II-1) or the bifunctional olefin compound represented by the chemical formula (II-2) is used alone in the reaction as the bifunctional olefin compound, an epoxy-oxetane compound represented by the chemical formula (I-1) or an epoxy-oxetane compound represented by the chemical formula (I-2) can be obtained, respectively.

[0031] The olefin-oxetane compound represented by chemical formula (Ia) can be synthesized in the presence of a base (i), and a catalyst (ii) for promoting the reaction may be used. A reaction solvent (iii) may also be used as long as it does not inhibit the reaction. In addition, the reaction for epoxidizing the double bond of the compound can employ a general epoxidation (oxidation) method, such as a method using a peracid, a method using hydrogen peroxide with sodium tungstate as a catalyst, or a method using hydrogen peroxide together with a base in an acetonitrile-alcohol solvent.

[0032] Examples of the base (i) include hydrides, hydroxides, carbonates, hydrogencarbonates, alkoxides, and organic amine compounds of alkali metals or alkaline earth metals. Examples include sodium hydride, potassium hydride, sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, sodium alkoxides, potassium alkoxides (e.g., potassium t-butoxide), and triethylamine. The amount of the base used (charge amount) is preferably an appropriate ratio in the range of 1.1 to 20 times the molar amount of the oxetane compound having a leaving group used (charge amount).

[0033] Examples of the catalyst (ii) include quaternary ammonium salts, quaternary phosphonium salts, etc. Examples of quaternary ammonium salts include salts of tetrabutylammonium, tetramethylammonium, tetraethylammonium, tetrapropylammonium, tetrahexylammonium, tetraoctylammonium, tetradecylammonium, hexadecyltriethylammonium, dodecyltrimethylammonium, trioctylmethylammonium, octyltriethylammonium, benzyltrimethylammonium, benzyltriethylammonium, benzyltributylammonium, benzyldimethyloctadecylammonium, and phenyltrimethylammonium halides (fluorides, chlorides, bromides, iodides), etc.

[0034] Examples of quaternary phosphonium salts include salts such as halides (fluorides, chlorides, bromides, iodides) of tetrabutylphosphonium, tetramethylphosphonium, tetraethylphosphonium, tetrapropylphosphonium, tetrahexylphosphonium, tetradecylphosphonium, tetraoctylphosphonium, triethyloctadecylphosphonium, trioctylethylphosphonium, hexadecyltriethylphosphonium, tetraphenylphosphonium, and methyltriphenylphosphonium.

[0035] These substances may be combined and used as catalyst (ii). The amount (charge amount) of catalyst (ii) used is preferably an appropriate ratio in the range of 0.0001 to 1.0 times the molar amount (charge amount) of the oxetane compound having a leaving group.

[0036] The reaction solvent (iii) is not particularly limited as long as it does not inhibit the reaction, and examples thereof include solvents such as water, tetrahydrofuran, diethyl ether, dioxane, 4-methyltetrahydropyran, dimethoxyethane, ethyl acetate, propyl acetate, butyl acetate, propylene glycol monomethyl ether acetate (PGMEA), acetonitrile, benzene, toluene, xylene, dichloromethane, chloroform, carbon tetrachloride, N,N-dimethylformamide (DMF), dimethylacetamide (DMA), dimethyl sulfoxide (DMSO), and hexamethylphosphoric triamide (HMPA). One or more solvents selected from these may be used in combination in appropriate amounts.

[0037] The reaction temperature when synthesizing the olefin-oxetane compound represented by chemical formula (Ia) is preferably set in the range of 0 to 150° C., more preferably in the range of 20 to 120° C. The reaction time is appropriately set depending on the set reaction temperature, but is preferably set in the range of 1 to 48 hours.

[0038] After the reaction is complete, the olefin-oxetane compound, which is the precursor of the target product, can be separated and extracted from the resulting reaction solution by, for example, solvent extraction, etc. If necessary, the product can be further purified by washing with water, treatment with activated carbon, silica gel chromatography, etc.

[0039] In the reaction of epoxidizing an olefin-oxetane compound using the peracid, peracids such as Oxone reagent, peracetic acid, metachloroperbenzoic acid (3-chloroperbenzoic acid), etc. The amount of peracid used (charged amount) is preferably an appropriate ratio in the range of 1.0 to 5.0 times the molar amount of the double bond in the olefin-oxetane compound.

[0040] In this epoxidation reaction, the reaction solvent is not particularly limited as long as it does not inhibit the reaction, and examples thereof include alcohols such as water, methanol, ethanol, and 2-propanol, aliphatic hydrocarbons such as hexane and heptane, ketones such as acetone and 2-butanone, esters such as ethyl acetate and butyl acetate, aromatic hydrocarbons such as benzene, toluene, and xylene, halogenated hydrocarbons such as methylene chloride (dichloromethane), chloroform, carbon tetrachloride, chlorotrifluoromethane, dichloroethane, chlorobenzene, and dichlorobenzene, ethers such as diethyl ether, diisopropyl ether, tetrahydrofuran, dioxane, dimethoxyethane, and diethylene glycol dimethyl ether, amides such as formamide, N,N-dimethylformamide (DMF), dimethylacetamide (DMA), N-methyl-2-pyrrolidone, N-methylpyrrolidinone, and hexamethylphosphorotriamide, and sulfoxides such as dimethyl sulfoxide (DMSO). These reaction solvents can be used alone or in combination of two or more in appropriate amounts.

[0041] The reaction temperature in this epoxidation reaction is usually set in the range of −10 to 150° C., preferably in the range of 0 to 100° C. The reaction time is appropriately set depending on the reaction temperature, but is usually set in the range of 1 to 48 hours, preferably in the range of 1 to 24 hours.

[0042] After the reaction is completed, the target epoxy-oxetane compound represented by chemical formula (I) can be separated and extracted from the resulting reaction solution by, for example, solvent extraction, etc. If necessary, the compound can be further purified by washing with water, treatment with activated carbon, silica gel chromatography, etc.

[0043] In the reaction of epoxidizing an olefin-oxetane compound using hydrogen peroxide and sodium tungstate as a catalyst, hydrogen peroxide is used in a molar ratio of 1.0 to 5.0 times the double bond of the olefin-oxetane compound. The amount of sodium tungstate used (charge amount) is preferably an appropriate ratio in the range of 0.001 to 0.5 times the double bond of the olefin-oxetane compound.

[0044] The epoxidation reaction is not particularly limited as long as it does not inhibit the reaction, and for example, the same reaction solvents as those used in the above-mentioned epoxidation using a peracid can be used.

[0045] The reaction temperature in this epoxidation reaction is set to be generally in the range of −10 to 150° C., preferably in the range of 0 to 100° C., as in the case of the above-mentioned epoxidation using a peracid. The reaction time is appropriately set depending on the reaction temperature, but is generally set to be in the range of 1 to 48 hours, preferably in the range of 1 to 24 hours.

[0046] After the reaction is complete, the epoxy-oxetane compound represented by formula (I) can be separated and extracted from the resulting reaction mixture by, for example, solvent extraction, in the same manner as in the case of the epoxidation using a peracid. If necessary, it may be purified.

[0047] In the reaction of epoxidizing an olefin-oxetane compound using hydrogen peroxide together with a base in an acetonitrile-alcohol solvent, the amount of hydrogen peroxide used (charge amount) is preferably an appropriate ratio within the range of 1.0 to 5.0 times the molar ratio of the double bond possessed by the olefin-oxetane compound. The amount of acetonitrile used (charge amount) is preferably an appropriate ratio within the range of 0.5 to 5.0 times the molar ratio of the olefin-oxetane compound. The amount of alcohol used (charge amount) is preferably an appropriate ratio within the range of 10 to 80% by weight before the addition of hydrogen peroxide. The pH is preferably set within the range of 7 to 13 using a base.

[0048] The alcohol used in this epoxidation is preferably a saturated alcohol having 1 to 4 carbon atoms, such as methanol, ethanol, n-propanol, 2-propanol, n-butanol, sec-butanol (2-butanol), and isobutanol (2-methyl-1-propanol). These alcohols may be used alone or in combination of two or more in appropriate amounts.

[0049] The base used in this epoxidation includes hydroxides, carbonates or hydrogencarbonates of alkali metals or alkaline earth metals, or organic amine compounds. It is preferable to use sodium hydroxide, potassium hydroxide, potassium carbonate or potassium hydrogencarbonate, and an appropriate amount of one or a combination of two or more types is used.

[0050] The reaction temperature for this epoxidation is set, as in the case of the above-mentioned epoxidation using a peracid, usually in the range of −10 to 150° C., preferably in the range of 0 to 100° C. The reaction time is appropriately set depending on the reaction temperature, but is usually set in the range of 1 to 48 hours, preferably in the range of 1 to 24 hours.

[0051] After the reaction is complete, the epoxy-oxetane compound represented by formula (I) can be separated and extracted from the resulting reaction mixture by, for example, solvent extraction, in the same manner as in the case of the epoxidation using a peracid. If necessary, it may be purified.

[0052] <Regarding the Curable Composition According to One Aspect of the Present Invention> The epoxy-oxetane compound represented by chemical formula (I) exhibits excellent curing performance. That is, a curable composition containing the epoxy-oxetane compound represented by chemical formula (I) (hereinafter sometimes referred to as the "first curable compound") can be cured to obtain a cured product (resin) that is expected to exhibit excellent properties. Note that in the curable composition according to one aspect of the present invention, the first curable compound can also be used in combination with another curable compound (hereinafter sometimes referred to as the "second curable compound").

[0053] When the curable composition according to one aspect of the present invention is cured (polymerized), a cured product can be obtained in which the first curable compound and the second curable compound are copolymerized by adding a second curable compound separately from the first curable compound. The second curable compound includes both a polymerizable monomer and a polymerizable oligomer (semi-cured product) having a structure in which the polymerizable monomer is polymerized.

[0054] Examples of this polymerizable monomer include known epoxy compounds (note: sometimes called epoxy resins), oxetane compounds, epoxy-oxetane compounds (having an oxirane ring and an oxetane ring in the molecule), and acrylic compounds (note: sometimes called acrylic resins).

[0055] The epoxy compound can be used without any particular limitation as long as it has an oxirane ring (epoxy group / glycidyl group) in the molecule, and examples thereof include: polyglycidyl ethers obtained by reacting epichlorohydrin with polyhydric phenols such as bisphenol A, bisphenol F, bisphenol AD, catechol, and resorcinol, or polyhydric alcohols such as glycerin and polyethylene glycol; glycidyl ether esters obtained by reacting epichlorohydrin with hydroxycarboxylic acids such as p-hydroxybenzoic acid and β-hydroxynaphthoic acid; polyglycidyl esters obtained by reacting epichlorohydrin with polycarboxylic acids such as phthalic acid and terephthalic acid; glycidyl glycoluril compounds having two or more epoxy groups in the molecule, such as 1,3,4,6-tetraglycidyl glycoluril; alicyclic epoxy compounds such as 3',4'-epoxycyclohexylmethyl 3,4-epoxycyclohexanecarboxylate; nitrogen-containing cyclic epoxy compounds such as triglycidyl isocyanurate and hydantoin-type epoxy compounds; Further examples include epoxidized phenol novolac resins, epoxidized cresol novolac resins, epoxidized polyolefins, alicyclic epoxy resins, and urethane-modified epoxy resins, as well as epoxy-modified organopolysiloxane compounds obtained by a hydrosilylation addition reaction between an organic compound having a carbon-carbon double bond and a glycidyl group and a silicon compound having a SiH group (for example, the epoxy-modified organopolysiloxane compounds disclosed in JP-A-2004-99751 and JP-A-2006-282988), and these may be used in combination.

[0056] The oxetane compound can be used without any particular limitation as long as it has an oxetane ring (oxetanyl group / oxetane group) in the molecule, and examples thereof include 3-ethyl-3-hydroxymethyloxetane, 3-(meth)allyloxymethyl-3-ethyloxetane, (3-ethyl-3-oxetanylmethoxy)methylbenzene, 4-fluoro-[1-(3-ethyl-3-oxetanylmethoxy)methyl]benzene, 4-methoxy-[1-(3-ethyl-3-oxetanylmethoxy)methyl]benzene, [1-(3-ethyl-3-oxetanylmethoxy)ethyl]phenyl ether, isobutoxymethyl(3-ethyl-3-oxetanylmethyl)ether, isobornyloxyethyl(3-ethyl-3-oxetanylmethyl)ether, isobornyl(3-ethyl-3-oxetanylmethyl)ether, 2-ethylhexyl (3-ethyl-3-oxetanylmethyl) ether, ethyl diethylene glycol (3-ethyl-3-oxetanylmethyl) ether, dicyclopentadiene (3-ethyl-3-oxetanylmethyl) ether, dicyclopentenyloxyethyl (3-ethyl-3-oxetanylmethyl) ether, dicyclopentenyl (3-ethyl-3-oxetanylmethyl) ether, tetrahydrofurfuryl (3-ethyl-3-oxetanylmethyl) ether, 2-hydroxyethyl (3-ethyl-3-oxetanylmethyl) ether, 2-hydroxypropyl (3-ethyl-3-oxetanylmethyl) ether, butoxyethyl (3-ethyl-3-oxetanylmethyl) ether, bornyl (3-ethyl-3-oxetanylmethyl) ether, 3,7-bis(3-oxetanyl)-5-oxa-nonane, 3,3'-[1,3-(2-methyleneyl)propanediylbis(oxymethylene)]bis-(3-ethyloxetane), 1,4-bis[(3-ethyl-3-oxetanylmethoxy)methyl]benzene, 1,2-bis[(3-ethyl-3-oxetanylmethoxy)methyl]ethane, 1,3-bis[(3-ethyl-3-oxetanylmethoxy)methyl]propane, ethylene glycol bis(3-ethyl-3-oxetanylmethyl) ether, dicyclopentenyl bis(3-ethyl-3-oxetanylmethyl) ether, triethylene glycol bis(3-ethyl-3-oxetanylmethyl) ether, tetraethylene glycol bis(3-ethyl-3-oxetanylmethyl) ether, tricyclodecanediyldimethylene(3-ethyl-3-oxetanylmethyl) ether, trimethylolpropane tris(3-ethyl-3-oxetanylmethyl) ether, 1,4-bis(3-ethyl-3-oxetanylmethoxy)butane, 1,6-bis(3-ethyl-3-oxetanylmethoxy)hexane, pentaerythritol tris(3-ethyl-3-oxetanylmethyl) ether, Pentaerythritol tetrakis(3-ethyl-3-oxetanylmethyl) ether, polyethylene glycol bis(3-ethyl-3-oxetanylmethyl) ether, dipentaerythritol hexakis(3-ethyl-3-oxetanylmethyl) ether, dipentaerythritol pentakis(3-ethyl-3-oxetanylmethyl) ether, dipentaerythritol tetrakis(3-ethyl-3-oxetanylmethyl) ether, caprolactone-modified dipentaerythritol hexakis(3-ethyl-3-oxetanylmethyl) ether, caprolactone-modified dipentaerythritol pentakis(3-ethyl-3-oxetanylmethyl) ether, ditrimethylolpropane tetrakis(3-ethyl-3-oxetanylmethyl) ether, EO-modified bisphenol A bis(3-ethyl-3-oxetanylmethyl) ether, Examples include PO-modified bisphenol A bis(3-ethyl-3-oxetanylmethyl) ether, EO-modified hydrogenated bisphenol A bis(3-ethyl-3-oxetanylmethyl) ether, PO-modified hydrogenated bisphenol A bis(3-ethyl-3-oxetanylmethyl) ether, and EO-modified bisphenol F(3-ethyl-3-oxetanylmethyl) ether.

[0057] The epoxy-oxetane compound can be any compound having an oxirane ring (same as above) and an oxetane ring (same as above) in the molecule, and examples thereof include those described in the aforementioned Patent Documents 1 and 2. The epoxy-oxetane compounds described in these documents are incorporated by reference into the disclosure of this specification.

[0058] Examples of the acrylic compound include allyl (meth)acrylate, vinyl (meth)acrylate, dicyclopentenyl (meth)acrylate, dicyclopentenyloxyethyl (meth)acrylate, (meth)acrylic acid-modified allyl glycidyl ether (manufactured by Nagase ChemteX Corporation, "Denacol Acrylate DA111 (trade name)"), urethane (meth)acrylates, epoxy (meth)acrylates, trimethylolpropane tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, ditrimethylolpropane tetra(meth)acrylate, dipentaerythritol hexa(meth)acrylate, butanediol di(meth)acrylate, nonanediol di(meth)acrylate, polypropylene glycol (meth)acrylate, bisphenol A di(meth)acrylate, tris(2-(meth)acryloyloxyethyl)isocyanurate, and (meth)acrylate group-containing polyorganosiloxane.

[0059] In the curable composition according to one embodiment of the present invention, the second curable compound may be a combination of the polymerizable monomer and polymerizable oligomer described above, and as the polymerizable monomer, the polymerizable monomers exemplified above may be a combination (different types of polymerizable monomers may be a combination), and as the polymerizable oligomer, different types of polymerizable oligomers may be a combination.

[0060] Regarding the ratio of the content of the first curable compound to the content of the second curable compound in the curable composition according to one aspect of the present invention, the content of the second curable compound is preferably an appropriate ratio in the range of 0 to 1000 times (weight ratio) the content of the first curable compound, and more preferably an appropriate ratio in the range of 0.01 to 100 times (weight ratio).

[0061] Methods for curing (polymerizing) the curable composition according to one embodiment of the present invention include photocuring and thermal curing. Examples of photocuring methods include a method of irradiating with active energy rays and a method of using a photopolymerization initiator in combination. Active energy rays include light, radiation, electromagnetic waves, electron beams, and the like, but typically refer to light, particularly ultraviolet rays. As the photopolymerization initiator, a photocationic polymerization initiator or a photoanionic polymerization initiator can be used, and if necessary, a photoradical polymerization initiator can be used in combination, and these can be contained in the curable composition. Photocuring may also be combined with thermal curing to improve production efficiency and the properties of the cured product.

[0062] As the cationic photopolymerization initiator, any commonly used one can be used without any particular limitation, and examples thereof include onium salts and organometallic complexes. Examples of onium salts include diazonium salts, sulfonium salts, and iodonium salts, and examples of organometallic complexes include iron-allene complexes, titanocene complexes, and arylsilanol-aluminum complexes. Examples of industrial chemicals commercially available as cationic photopolymerization initiators include "OPTOMER SP-150 (trade name)" and "OPTOMER SP-170 (trade name)" manufactured by ADEKA Corporation, "CPI-100P (trade name)" manufactured by San-Apro, "UVE-1014 (trade name)" manufactured by General Electronics Corporation, and "CD-1012 (trade name)" manufactured by Sartomer. Examples of the counter anion of the cationic photopolymerization initiator include SbF ６ － , AsF ６ － , B(C ６ F ５ ) ４ － , P.F. ６ － etc.

[0063] Any commonly used photoanionic polymerization initiator can be used without particular limitation, and examples thereof include onium salts and carbamates. Examples of onium salts include 1,2-diisopropyl-3-(bis(dimethylamino)methylene)guanidium 2-(3-benzoylphenyl)propionate and 1,2-dicyclohexyl-4,4,5,5-tetramethylbiguanidium n-butyltriphenylborate. Examples of carbamates include 2-nitrophenylmethylpiperidine-1-carboxylate, 1-(anthraquinone-2-yl)ethylimidazolecarboxylate, 1-(3-(2-hydroxyphenyl)-2-propenoyl)piperidine, and 9-anthranylmethyldiethylcarbamate.

[0064] The content of the photocationic polymerization initiator or the photoanionic polymerization initiator in the curable composition according to one aspect of the present invention is preferably 0.001 to 20% by weight, and more preferably 0.01 to 10% by weight.

[0065] Examples of the photoradical polymerization initiator include ketal compounds having 16 to 17 carbon atoms (e.g., acetophenone dimethyl ketal, benzyl dimethyl ketal, etc.), acetophenone compounds having 8 to 18 carbon atoms (e.g., acetophenone, 2,2-dimethoxy-2-phenylacetophenone, 2,2-diethoxy-2-phenylacetophenone, 1,1-dichloroacetophenone, 2-hydroxy-2-methyl-phenylpropan-1-one, diethoxyacetophenone, 1-hydroxycyclohexyl phenyl ketone, 2-methyl-1-[4-(methylthio)phenyl]-2-morpholinopropan-1-one, etc.), Benzophenone compounds having 13 to 21 carbon atoms (e.g., benzophenone, 4-benzoyl-4'-methyldiphenyl sulfide, 4,4'-bismethylaminobenzophenone, etc.), benzoin compounds having 14 to 18 carbon atoms (e.g., benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin propyl ether, benzoin isobutyl ether, etc.), anthraquinone compounds having 14 to 19 carbon atoms (e.g., 2-ethylanthraquinone, 2-tert-butylanthraquinone, 2-chloroanthraquinone, 2-amylanthraquinone, etc.), thioxanthone compounds having 13 to 17 carbon atoms (e.g., 2,4-diethylthioxanthone, 2-isopropylthioxanthone, 2-chlorothioxanthone, etc.), Examples of the acylphosphine oxide compounds include those having 22 to 28 carbon atoms (for example, 2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide, bis-(2,6-dimethoxybenzoyl)-2,4,4-trimethylpentylphosphine oxide, and bis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide).

[0066] The content of the photoradical polymerization initiator in the curable composition according to one embodiment of the present invention is preferably 0.001 to 20% by weight, and more preferably 0.01 to 10% by weight.

[0067] When photocuring the curable composition according to one aspect of the present invention, a sensitizer such as pyrene, perylene, acridine orange, thioxanthone, 2-chlorothioxanthone, or benzoflavin can be used.

[0068] On the other hand, when thermally curing the curable composition according to one embodiment of the present invention, a thermal polymerization initiator can be used. As the thermal polymerization initiator, a thermal cationic polymerization initiator, a thermal radical polymerization initiator, or a thermal anionic polymerization initiator can be adopted, and this may be contained in the curable composition.

[0069] The thermal cationic polymerization initiator can be any commonly used one without particular limitation, and examples thereof include various onium salts such as quaternary ammonium salts, phosphonium salts, and sulfonium salts, as well as organometallic complexes. Examples of onium salts commercially available as industrial chemicals include "ADEKAOPTON CP-66 (trade name)" and "ADEKAOPTON CP-77 (trade name)" manufactured by ADEKA Corporation, "SAN-AID SI-60L (trade name)," "SAN-AID SI-80L (trade name)," and "SAN-AID SI-100L (trade name)" manufactured by Sanshin Chemical Industry Co., Ltd., and "CI Series (trade name)" manufactured by Nippon Soda Co., Ltd. Furthermore, examples of organometallic complexes include alkoxysilane-aluminum complexes.

[0070] The thermal radical polymerization initiator can be any commonly used one without any particular limitation, and examples thereof include diisopropyl peroxydicarbonate, benzoyl peroxide, t-butyl peroxyisobutyrate, t-hexyl peroxyisopropyl monocarbonate, t-hexyl peroxy 2-ethylhexanoate, 1,1,3,3-tetramethylbutyl peroxy 2-ethylhexanoate, t-butyl peroxypivalate, t-hexyl peroxypivalate, and t-butyl peroxyneodecanoate. peroxides such as benzoyl peroxide, t-hexylperoxyneodecanoate, 1,1,3,3-tetramethylbutylperoxyneodecanoate, 1,1-bis(t-hexylperoxy)cyclohexane, benzoyl peroxide, 3,5,5-trimethylhexanoyl peroxide, and lauroyl peroxide; and azo compounds such as azobisisobutyronitrile, 2,2'-azobis(2-methylbutyronitrile), and dimethyl 2,2'-azobis(2-methylpropionate), and these may be used in combination.

[0071] The thermal anionic polymerization initiator can be any commonly used one without any particular limitation, and examples thereof include amines, imidazoles, etc., and these may also be used in combination.

[0072] Regarding the thermal curing conditions, the heating temperature / heating time can be set appropriately, but it is preferable to set them in the range of 60 to 200°C / 30 to 240 minutes, and more preferably in the range of 70 to 180°C / 30 to 120 minutes.

[0073] The content of the thermal polymerization initiator in the curable composition according to one embodiment of the present invention is preferably 0.001 to 20% by weight, and more preferably 0.01 to 10% by weight.

[0074] In the present invention, the cationic polymerization initiator refers to the above-mentioned photocationic polymerization initiator and / or thermal cationic polymerization initiator, the anionic polymerization initiator refers to the above-mentioned photoanionic polymerization initiator and / or thermal anionic polymerization initiator, and the radical polymerization initiator refers to the above-mentioned photoradical polymerization initiator and / or thermal radical polymerization initiator.

[0075] Another method for curing (polymerizing) the curable composition according to an embodiment of the present invention includes photocuring and thermal curing using a curing agent. When thermal curing is performed, a thermal polymerization initiator can be used in combination.

[0076] Examples of the curing agent include an acid anhydride compound, a thiol compound, and an amine compound.

[0077] Examples of the acid anhydride compound include methyltetrahydrophthalic anhydride, methylhexahydrophthalic anhydride, hexahydrophthalic anhydride, 5-norbornene-2,3-dicarboxylic anhydride, trimellitic anhydride, nadic anhydride, himic anhydride, methylnadic anhydride, methylbicyclo[2.2.1]heptane-2,3-dicarboxylic anhydride, bicyclo[2.2.1]heptane-2,3-dicarboxylic anhydride, and methylnorbornane-2,3-dicarboxylic acid.

[0078] Examples of thiol compounds include aliphatic thiol compounds such as ethanedithiol, propanedithiol, hexamethylenedithiol, decamethylenedithiol, tolylene-2,4-dithiol, 2,2-bis(mercaptomethyl)-1,3-propanedithiol, 2-(mercaptomethyl)-2-methyl-1,3-propanedithiol, and 2-ethyl-2-(mercaptomethyl)-1,3-propanedithiol; cyclic sulfide compounds such as 1,4-dithiane ring-containing polythiol compounds represented by formula (XIV); mercaptoalkyl sulfide compounds such as 3-thiapentane-1,5-dithiol and 4-mercaptomethyl-3,6-dithia-1,8-octanedithiol; mercaptopropionic acid esters such as pentaerythritol tetrakis(3-mercaptopropionate); epoxy resin terminal mercapto compounds; mercaptoalkyl ether compounds such as 3,6-dioxa-1,8-octanedithiol, mercaptoalkyl ether disulfide compounds represented by formula (XV), 2,2'-[[2,2-bis[(2-mercaptoethoxy)methyl]-1,3-propanediyl]bis(oxy)]bisethanethiol, 3,3'-[[2,2-bis[(3-mercaptopropoxy)methyl]-1,3-propanediyl]bis(oxy)]bis-1-propanethiol, 3-[2,2-bis[(3-mercaptopropoxy)methyl]butoxy]-1-propanethiol, 3-(3-mercaptopropoxy)-2,2-bis[(3-mercaptopropoxy)methyl]-1-propanol, and 2,2-bis[(3-mercaptopropoxy)methyl]-1-butanol; Examples of the other thiol compounds include 1,3,4,6-tetrakis(2-mercaptoethyl)glycoluril and 1,3,4,6-tetrakis(3-mercaptopropyl)glycoluril, with 1,3,4,6-tetrakis(2-mercaptoethyl)glycoluril and 1,3,4,6-tetrakis(3-mercaptopropyl)glycoluril being preferred. These other thiol compounds may be used alone or in combination of two or more.

[0079] (In the formula, p represents an integer of 1 to 5.)

[0080] (In the formula, q represents an integer of 1 to 20.)

[0081] As has been conventionally known, the amine compound may be any compound having at least one amino group selected from a primary amino group, a secondary amino group, and a tertiary amino group in the molecule.

[0082] Examples of such amine compounds include aliphatic amines such as diethylenetriamine, triethylenetetramine, isophoronediamine, xylylenediamine, diaminodiphenylmethane, 1,3,4,6-tetrakis(3-aminopropyl)glycoluril, n-propylamine, 2-hydroxyethylaminopropylamine, cyclohexylamine, 4,4'-diaminodicyclohexylmethane, and dimethylbenzylamine; aromatic amines such as 4,4'-diaminodiphenylmethane and o-methylaniline; and nitrogen-containing heterocyclic compounds such as 2-ethyl-4-methylimidazole, 2-methylimidazole, 2-ethyl-4-methylimidazoline, 2,4-dimethylimidazoline, piperidine, and piperazine.

[0083] The content of the curing agent in the curable composition according to one embodiment of the present invention is preferably 0.1 to 50 parts by weight, more preferably 1 to 40 parts by weight, relative to 100 parts by weight of the epoxy-oxetane compound.

[0084] The reaction product of an epoxy compound with an amine compound or the reaction product of a compound having one or more isocyanate groups in the molecule with a compound having at least one of a primary amino group and a secondary amino group in the molecule is a solid that is hardly soluble in epoxy resins at room temperature, but becomes solubilized (easily soluble) by heating and functions as a curing accelerator, and is therefore also called a latent curing accelerator (hereinafter, these reaction products may be referred to as "latent curing accelerators").

[0085] Examples of epoxy compounds used as a raw material for the latent curing accelerator comprising a reaction product of an epoxy compound and an amine compound include, in addition to the above-mentioned epoxy compounds, glycidylamine compounds obtained by reacting epichlorohydrin with 4,4'-diaminodiphenylmethane, m-aminophenol, or the like; and monofunctional epoxy compounds such as butyl glycidyl ether, phenyl glycidyl ether, and glycidyl methacrylate.

[0086] Examples of amine compounds used as raw materials for latent curing accelerators consisting of reaction products of epoxy compounds and amine compounds include the above-mentioned amine compounds. Among these amine compounds, amine compounds having a tertiary amino group in the molecule are raw materials that provide latent curing accelerators with excellent curing acceleration properties.Examples of such amine compounds include amines such as dimethylaminopropylamine, diethylaminopropylamine, di-n-propylaminopropylamine, dibutylaminopropylamine, dimethylaminoethylamine, diethylaminoethylamine, and N-methylpiperazine; amines having a tertiary amino group in the molecule, such as imidazole compounds such as 2-methylimidazole, 2-ethylimidazole, 2-ethyl-4-methylimidazole, and 2-phenylimidazole; 2-Dimethylaminoethanol, 1-methyl-2-dimethylaminoethanol, 1-phenoxymethyl-2-dimethylaminoethanol, 2-diethylaminoethanol, 1-butoxymethyl-2-dimethylaminoethanol, 1-(2-hydroxy-3-phenoxypropyl)-2-methylimidazole, 1-(2-hydroxy-3-phenoxypropyl)-2-ethyl-4-methylimidazole, 1-(2-hydroxy-3-butoxypropyl)-2-methylimidazole, 1-(2-hydroxy-3-butoxypropyl)-2-ethyl-4-methylimidazole, 1-(2-hydroxy-3-phenoxypropyl)-2-phenylimidazoline, 1-(2-hydroxy-3-butoxypropyl)-2-methyl Examples of the tertiary amino acid include alcohols, phenols, thiols, carboxylic acids, and hydrazides having a tertiary amino group in the molecule, such as methylimidazoline, 2-(dimethylaminomethyl)phenol, 2,4,6-tris(dimethylaminomethyl)phenol, N-β-hydroxyethylmorpholine, 2-dimethylaminoethanethiol, 2-mercaptopyridine, 2-mercaptobenzimidazole, 2-mercaptobenzothiazole, 4-mercaptopyridine, N,N-dimethylaminobenzoic acid, N,N-dimethylglycine, nicotinic acid, isonicotinic acid, picolinic acid, N,N-dimethylglycine hydrazide, N,N-dimethylpropionic acid hydrazide, nicotinic acid hydrazide, and isonicotinic acid hydrazide.

[0087] In order to further improve the storage stability of the curable composition related to one aspect of the present invention, an active hydrogen compound having two or more active hydrogens in the molecule may be used as a third component in addition to the epoxy compound and amine compound as raw materials for the latent curing accelerator composed of the reaction product of the epoxy compound and the amine compound.

[0088] Examples of active hydrogen compounds include polyhydric phenols such as bisphenol A, bisphenol F, bisphenol S, hydroquinone, catechol, resorcinol, pyrogallol, and phenol novolac resin; polyhydric alcohols such as trimethylolpropane; polycarboxylic acids such as adipic acid and phthalic acid; 1,2-dimercaptoethane, 2-mercaptoethanol, 1-mercapto-3-phenoxy-2-propanol, mercaptoacetic acid, anthranilic acid, and lactic acid.

[0089] Furthermore, the latent curing accelerator consisting of the reaction product of an epoxy compound and an amine compound may be surface-treated with an isocyanate compound or an acidic compound. Examples of the isocyanate compound include monofunctional isocyanate compounds such as n-butyl isocyanate, isopropyl isocyanate, phenyl isocyanate, and benzyl isocyanate; and polyfunctional isocyanate compounds such as hexamethylene diisocyanate, toluylene diisocyanate, 1,5-naphthalene diisocyanate, diphenylmethane-4,4'-diisocyanate, isophorone diisocyanate, xylylene diisocyanate, paraphenylene diisocyanate, 1,3,6-hexamethylene triisocyanate, and bicycloheptane triisocyanate.

[0090] Instead of this polyfunctional isocyanate compound, a compound containing a terminal isocyanate group obtained by reacting a polyfunctional isocyanate compound with an active hydrogen compound can also be used in the same manner as the polyfunctional isocyanate compound. Examples of such a compound containing a terminal isocyanate group include an addition reaction product having a terminal isocyanate group obtained by reacting toluylene diisocyanate with trimethylolpropane, and an addition reaction product having a terminal isocyanate group obtained by reacting toluylene diisocyanate with pentaerythritol.

[0091] The acidic compound used for the surface treatment of the latent curing accelerator comprising the reaction product of an epoxy compound and an amine compound may be any of a gas, liquid, or solid, and may be any of an inorganic acid and an organic acid. Examples of such acidic compounds include carbon dioxide gas, sulfurous acid gas, sulfuric acid, hydrochloric acid, oxalic acid, phosphoric acid, acetic acid, formic acid, propionic acid, adipic acid, caproic acid, lactic acid, succinic acid, tartaric acid, sebacic acid, p-toluenesulfonic acid, salicylic acid, boric acid, tannic acid, alginic acid, polyacrylic acid, polymethacrylic acid, phenol, pyrogallol, phenolic resin, and resorcinol resin.

[0092] A latent curing accelerator consisting of a reaction product of an epoxy compound and an amine compound can be easily obtained by mixing an epoxy compound, an amine compound, and, if necessary, an active hydrogen compound, reacting them at a temperature of from room temperature to 200°C, solidifying the mixture, and pulverizing the mixture; alternatively, by reacting the mixture in a solvent such as methyl ethyl ketone, dioxane, or tetrahydrofuran, removing the solvent, and pulverizing the solid content.

[0093] Alternatively, a commercially available latent curing accelerator consisting of a reaction product of an epoxy compound and an amine compound can be used. Examples of commercially available products include "Amicure PN-23 (trade name)," "Amicure PN-H (trade name)," "Amicure PN-50 (trade name)," "Amicure PN-23J (trade name)," "Amicure PN-40J (trade name)," and "Amicure MY-24 (trade name)" manufactured by Ajinomoto Fine-Techno Co., Ltd.; "Novacure HX-3088 (trade name)," "Novacure HX-3721 (trade name)," "Novacure HX-3722 (trade name)," "Novacure HX-3742 (trade name)," "Novacure HX-3941HP (trade name)," and "Novacure HXA3922HP (trade name)" manufactured by Asahi Kasei Corporation; and T&K Examples include Fujicure FXR-1030 (trade name), Fujicure FXR-1081 (trade name), and Fujicure FXR-1121 (trade name) manufactured by TOKA Corporation.

[0094] In the curable composition according to one aspect of the present invention, the content of the latent curing accelerator formed from a reaction product of an epoxy compound and an amine compound is preferably 0.1 to 100 parts by weight, more preferably 1 to 90 parts by weight, and even more preferably 1 to 80 parts by weight, relative to 100 parts by weight of the epoxy-oxetane compound.

[0095] Examples of isocyanate compounds having one or more isocyanate groups in the molecule used as a raw material for the latent curing accelerator consisting of a reaction product of a compound having one or more isocyanate groups in the molecule and a compound having at least one of a primary amino group and a secondary amino group in the molecule include n-butyl isocyanate, isopropyl isocyanate, 2-chloroethyl isocyanate, phenyl isocyanate, p-bromophenyl isocyanate, m-chlorophenyl isocyanate, o-chlorophenyl isocyanate, p-chlorophenyl isocyanate, 2,5-dichlorophenyl isocyanate, 3,4-dichlorophenyl isocyanate, 2,6-dimethylphenyl isocyanate, o-fluorophenyl isocyanate, p-fluorophenyl isocyanate, m-tolyl isocyanate, p-tolyl isocyanate, o-trifluoromethylphenyl isocyanate, m-trifluoromethylphenyl isocyanate, benzyl isocyanate, hexamethylene Examples of the isocyanate include diphenylmethane diisocyanate, 2,4-toluylene diisocyanate, 2,6-toluylene diisocyanate, 1,5-naphthalene diisocyanate, diphenylmethane-4,4'-diisocyanate, 2,2-dimethyldiphenylmethane-4,4'-diisocyanate, tolidine diisocyanate, isophorone diisocyanate, xylylene diisocyanate, 1,3-bis(isocyanatomethyl)cyclohexane, p-phenylene diisocyanate, 1,3,6-hexamethylene triisocyanate, bicycloheptane triisocyanate, tris-(3-isocyanato-4-methylphenyl)isocyanurate, and tris-(6-isocyanatohexyl)isocyanurate.

[0096] Examples of compounds having at least one of a primary amino group and a secondary amino group in the molecule that can be used as a raw material for the latent curing accelerator, which is a reaction product of a compound having one or more isocyanate groups in the molecule and a compound having at least one of a primary amino group and a secondary amino group in the molecule, include: Examples thereof include dimethylamine, diethylamine, di-n-propylamine, di-n-butylamine, di-n-hexylamine, di-n-octylamine, di-n-ethanolamine, dimethylaminopropylamine, diethylaminopropylamine, morpholine, piperidine, 2,6-dimethylpiperidine, 2,2,6,6-tetramethylpiperidine, piperazine, pyrrolidine, benzylamine, N-methylbenzylamine, cyclohexylamine, metaxylylenediamine, 1,3-bis(aminomethyl)cyclohexane, isophoronediamine, N-aminoethylpiperazine, 2-methylimidazole, 2-ethyl-4-methylimidazole, 2-undecylimidazole, 2-phenylimidazole, and 1,1-dimethylhydrazine.

[0097] A reaction product of a compound having one or more isocyanate groups in the molecule and a compound having at least one of a primary amino group and a secondary amino group in the molecule can be obtained by reacting the two in an organic solvent such as dichloromethane.

[0098] In the curable composition according to one aspect of the present invention, the content of the latent curing accelerator formed from a reaction product of a compound having one or more isocyanate groups in the molecule and a compound having at least one of a primary amino group and a secondary amino group in the molecule is preferably 1 to 10 parts by weight relative to 100 parts by weight of the epoxy oxetane compound.

[0099] The curable composition according to one embodiment of the present invention may further contain, as long as the effects of the present invention are not impaired, pigments (titanium white, cyanine blue, watching red, red iron oxide, carbon black, aniline black, manganese blue, iron black, ultramarine blue, Hansa red, chrome yellow, chrome green, etc.), inorganic fillers (calcium carbonate, kaolin, clay, talc, mica, barium sulfate, lithopone, gypsum, zinc stearate, perlite, quartz, quartz glass, silica powders such as fused silica and spherical silica, oxides such as spherical alumina, crushed alumina, magnesium oxide, beryllium oxide, and titanium oxide, nitrides such as boron nitride, silicon nitride, and aluminum nitride, carbides such as silicon carbide, hydroxides such as aluminum hydroxide and magnesium hydroxide, metals and alloys such as copper, silver, iron, aluminum, nickel, and titanium, and carbon-based materials such as diamond and carbon). Thermoplastic resins and thermosetting resins (homopolymers such as various high-density, medium-density, and low-density polyethylenes, polypropylene, polybutene, and polypentene, ethylene-propylene copolymers, polyamide resins such as nylon-6 and nylon-6,6, vinyl chloride resins, nitrocellulose resins, vinylidene chloride resins, acrylamide resins, styrene resins, vinyl ester resins, polyester resins, phenolic resins (phenolic compounds), silicone resins, fluorine-based resins, various elastomer resins such as acrylic rubber and urethane rubber, graft copolymers such as methyl methacrylate-butadiene-styrene graft copolymers and acrylonitrile-butadiene-styrene graft copolymers), reinforcing agents (glass fiber, carbon fiber, etc.), anti-sagging agents (hydrogenated castor oil, fine particle silicic anhydride, etc.), matting agents (fine powder silica, paraffin wax, etc.), abrasives (zinc stearate, etc.), The composition may contain additives (modifiers) such as an internal mold release agent (a fatty acid such as stearic acid, a fatty acid metal salt of calcium stearate, a fatty acid amide such as stearic acid amide, a fatty acid ester, a polyolefin wax, a paraffin wax, etc.), a surfactant, a leveling agent, an antifoaming agent, a viscosity adjusting diluent (organic solvent), a coupling agent, a fragrance, a flame retardant, etc.

[0100] The curable composition according to one embodiment of the present invention can be prepared by any method without particular limitations, and can be prepared by weighing out predetermined amounts of the above-described components and stirring and mixing them. For example, the composition can be prepared by premixing, followed by mixing or melt-kneading using a roll mixer, kneader, extruder, or the like. If necessary, an organic solvent (a viscosity-adjusting diluent) may be used.

[0101] The curable composition according to one embodiment of the present invention is polymerized (cured) by irradiation with ultraviolet light or heating to give a cured product. Examples of UV irradiation methods include methods using light sources such as chemical lamps, low-pressure mercury lamps, high-pressure mercury lamps, ultra-high-pressure mercury lamps, xenon lamps, and metal halide lamps. The UV irradiation intensity and irradiation time are appropriately set taking into account the desired irradiation intensity or desired irradiation time, as well as the composition and shape (thickness) of the curable composition to be irradiated. Examples of heating methods include hot air circulation, infrared heating, and high-frequency heating. Furthermore, curing devices such as sealed curing ovens and tunnel ovens capable of continuous curing can be used. The heating (curing) temperature and heating (curing) time can be appropriately set taking into account the composition and shape (thickness) of the curable composition to be irradiated, as in the case of UV irradiation.

[0102] The curable composition according to one embodiment of the present invention has low viscosity and can therefore be used as a curable ink composition. Furthermore, the curable composition according to one embodiment of the present invention has low viscosity and excellent ejection properties. Therefore, it is also suitable as an inkjet curable ink composition. By applying the inkjet curable ink composition to a predetermined object using an inkjet method and curing it, it can be used to manufacture various parts and components, as described below. The inkjet method can form a resin film quickly, uniformly, and over a wide area, which offers advantages such as improved product precision for the various parts and components, as described below, as well as reduced manufacturing costs.

[0103] From the viewpoint of volatility, the curable ink composition and the curable inkjet ink composition preferably have a 5% weight loss temperature (°C) of 185°C or higher, and more preferably 190°C or higher, as measured using a differential thermal thermogravimetry device under conditions of a sample weight of 10 mg, a temperature increase rate of 10°C / min, and a nitrogen flow of 200 mL / min.

[0104] The inkjet curable ink composition preferably has a viscosity of 5 mPa·s or more and 150 mPa·s or less, more preferably 10 mPa·s or more and 80 mPa·s or less, and even more preferably 10 mPa·s or more and 40 mPa·s or less, as measured at 25°C using a dynamic viscoelasticity measuring device (Rheosol-G5000, manufactured by UBM). The inkjet curable ink composition may be heated during application by the inkjet method to reduce the viscosity before application.

[0105] Furthermore, the curable inkjet ink composition preferably has a surface tension of 15 mN / m or more and 35 mN / m or less, and more preferably 20 mN / m or more and 30 mN / m or less, as measured at 25°C using a dynamic wettability tester.

[0106] Suitable examples of the inkjet curable ink composition include curable compositions for encapsulating optical elements, which are used as encapsulants for optical elements such as organic electroluminescence (hereinafter referred to as organic EL) elements and organic thin-film solar cell elements, adhesives for optical members, which are used for bonding optical lenses, curable compositions for stereolithography, which are used in the manufacture of various parts and members using 3D printers, and curable compositions for nanoimprinting, which are used in the formation of ultrafine circuit patterns for semiconductors.

[0107] As an example, a method for producing an optical element using the curable composition according to one embodiment of the present invention as a curable composition for encapsulating an optical element includes a step of applying the curable composition for encapsulating an optical element to at least one of two substrates by an inkjet method, a step of curing the applied curable composition for encapsulating an optical element by light irradiation and / or heat, and a step of bonding the two substrates together.

[0108] In the step of applying the curable composition for encapsulating optical elements to at least one of two substrates, the curable composition for encapsulating optical elements may be applied to the entire surface of the substrate, or may be applied to a part of the substrate. For example, when an organic EL element is produced as the optical element, the shape of the sealant portion formed by applying the curable composition for encapsulating optical elements is not particularly limited as long as it is a shape that can protect a laminate having an organic light-emitting material layer sandwiched between two substrates from the outside air. That is, it may be a shape that completely covers the laminate, or a pattern shape that closes the periphery of the laminate.

[0109] The step of curing the curable composition for encapsulating optical elements by light irradiation and / or heating may be carried out before the step of laminating the two substrates together, or may be carried out after the step of laminating the two substrates together. When the step of curing the curable composition for encapsulating optical elements by light irradiation and / or heating is carried out before the step of laminating the two substrates together, the substrates may be laminated together within a usable time (for example, 1 minute) from the time of light irradiation and / or heating until the curing reaction progresses and the substrates can no longer be bonded.

[0110] Furthermore, the step of curing the applied curable composition for encapsulating optical elements by light irradiation and / or heating may be carried out by the ultraviolet ray irradiation means and / or heating means described above.

[0111] The curable composition according to one embodiment of the present invention is not particularly limited in its application, and can be applied to products (components and members) in various fields where resin may be used as the material, and can be used as a raw material for materials in the fields of electricity and electronics, optics, architecture, civil engineering, automobiles and aircraft, and medicine, as well as for other daily necessities and miscellaneous goods.

[0112] For example, examples of parts, members, and materials in the electrical and electronic fields include resin-coated copper foil, prepreg, copper-clad laminate, printed wiring board, solder resist ink, anisotropic conductive film, anisotropic conductive paste, interlayer insulating material, adhesive, pressure-sensitive adhesive, sealing material, sealant (sealing material), sealing sheet, insulating material, thermally conductive material, hot melt material, paint, potting agent, etc., but more specific examples include: sealing materials (sealants) for printed wiring boards and electronic components such as interlayer insulating film and wiring coating film, sealing materials (sealants) for image display devices, sealing sheets for image display devices, sealing materials (sealants) for organic EL display elements, sealing sheets for organic EL display elements, and layer-forming materials; display device forming materials such as color filters, polarizing plates, display materials, resist materials, and alignment films; semiconductor device forming materials such as resist materials and buffer coat films; optical component forming materials such as lenses, holograms, optical waveguides, optical circuits, optical circuit components, and antireflection films; Coating agents such as surface protective films for semiconductor elements and organic thin-film elements (for example, organic electroluminescence elements and organic thin-film solar cell elements), hard coating agents, antifouling films and antireflection films, etc. Further examples include materials for organic electronic elements such as organic EL elements, organic transistors and solar cells, materials for forming rigid wiring boards and flexible printed wiring boards for semiconductor mounting, mounting materials for semiconductor mounting, adhesives for flexible printed wiring boards, semiconductor sealants, solar cell sealants, insulating films for semiconductors, coverlay films for protecting flexible printed circuits, and coating agents for wiring coating.

[0113] Examples of materials in the optical field include lenses, prisms, films, core materials for optical fibers, cladding materials, abrasion-resistant coating agents for plastic lenses, materials for stereolithography, optical waveguides, filters, image display materials, lens arrays, sealants and reflector materials for optical semiconductor elements, light guide plates, light diffusers, diffraction elements, and optical adhesives. For example, lenses and prisms are not particularly limited as long as they utilize refraction on their surfaces. They can also be used as: materials for lenses in camera modules, LiDAR modules, and still cameras; adhesives for finder prisms, target prisms, finder covers, light-receiving sensor units, photographic lenses, and projection lenses for projection televisions; optical fiber materials for the periphery of optical switches and optical connectors in optical communication systems; sealants and adhesives for optical passive components, optical circuit components, and the periphery of optoelectronic integrated circuits; and the like. Examples of bonding locations in a camera module include between an image sensor (imaging element) such as a CMOS or CCD and the substrate, between a cut filter and the substrate, between the substrate and the housing, between the housing and the cut filter, and between the housing and the lens unit.

[0114] Lenses and prisms include spherical lenses with spherical surfaces, such as convex lenses like biconvex lenses, plano-convex lenses, and convex meniscus lenses, and concave lenses like biconcave lenses, plano-concave lenses, and concave meniscus lenses; aspherical lenses, such as lenses with aspherical surfaces like symmetrical paraboloids, ellipsoids, hyperboloids, and polyhedral surfaces (for example, quartic surfaces), and lenses with free-form surfaces without an axis of symmetry; cylindrical lenses, such as semi-cylindrical cylindrical lenses; toroidal lenses, such as donut-shaped lenses with toroidal surfaces with different radii of curvature in the vertical and horizontal directions; thin Fresnel lenses, in which ring-shaped prisms, each with a reflective surface that changes the direction of light and a refracting surface that transmits light, are arranged concentrically on a plane, with the prisms becoming successively smaller or larger toward the center; and diffractive lenses, in which a fine relief with a depth on the order of the wavelength of light is formed concentrically; A prism having two or more optically flat surfaces, at least one pair of surfaces of which is substantially non-parallel, is also included. ２and SiO ２ Examples of such reflective films include those prepared by treating inorganic compounds such as those mentioned above by vacuum deposition, sputtering, or CVD, or by allowing a light absorber to coexist therewith, thereby transmitting light in a desired wavelength range while reflecting light in an undesired wavelength range.

[0115] Examples of materials in the construction field include joint sealants, coating materials, and primers for exterior materials such as various metal panels and siding boards; sealants, adhesives, injection materials, vibration-damping materials, soundproofing materials, conductive materials for electromagnetic wave shielding, and putty materials used between exterior materials, base materials, ceiling materials, and interior materials; adhesives for bonding tiles and stone to exterior wall materials and base materials; adhesives and pressure-sensitive adhesives for bonding wood flooring materials, polymer material floor sheets, and floor tiles to various floors; and injection materials for repairing cracks in various exterior and interior materials.

[0116] Examples of materials used in the civil engineering field include joint sealants, coating materials, primers, paints, putty materials, injection materials, spray materials, and formwork for various concrete products such as roads, bridges, tunnels, and breakwaters.

[0117] Examples of materials in the automotive and aircraft fields include structural materials, fiber-reinforced composites, adhesives for bodies and parts, sealing materials, coating materials, cushioning materials, vibration-damping materials, soundproofing materials, and spray materials; adhesives, pressure-sensitive adhesives, coating materials, and foam materials for automotive interiors; and sealing materials, adhesives, and coating materials for steel plate joints. Furthermore, examples of uses for substrates having a coating layer formed on their surfaces, which is made of a cured product of the curable composition according to one embodiment of the present invention, include components for various industrial equipment such as transportation vehicles (automobiles, aircraft, etc.) and electronic and electrical equipment (e.g., sliding components such as cylinders, pistons, and bearings).

[0118] Examples of materials in the medical field include artificial bones, dental impression materials, medical rubber materials, medical adhesives, and medical device sealing materials.

[0119] Other examples include paints that are applied to substrates such as metals, resin films, glass, paper, and wood.

[0120] [Summary] As described above, the present inventors have recognized that the desired object can be achieved by employing a curable composition containing an epoxy-oxetane compound represented by chemical formula (I), and have completed the present invention.

[0121] That is, the first invention is a curable composition containing an epoxy-oxetane compound represented by chemical formula (I).

[0122] (In the formula, R may be the same or different and represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms.)

[0123] It may also contain a cationic polymerization initiator.

[0124] A second invention is a cured product obtained by curing the curable composition of the first invention.

[0125] A third invention is an adhesive containing the curable composition of the first invention.

[0126] A fourth invention is a sealant containing the curable composition of the first invention.

[0127] The present invention will be described in more detail below using examples and comparative examples, but the present invention is not limited thereto. The main raw materials used are as follows. Allyl glycidyl ether (manufactured by Tokyo Chemical Industry Co., Ltd.) Allyl alcohol (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) Potassium tert-butoxide (manufactured by Tokyo Chemical Industry Co., Ltd.) 3-ethyl-3-methanesulfonyloxymethyloxetane (synthesized in accordance with the method described in JP 2007-332294 A) Sodium hydroxide (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) Metachloroperbenzoic acid (manufactured by Tokyo Chemical Industry Co., Ltd.) 1,2,3-glycidyloxypropane (manufactured by Anhui Xinyuan Technology Co., Ltd., trade name "XY633", a compound represented by chemical formula (IV)) Glycerin (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) 3-ethyl-3-hydroxymethyloxetane (manufactured by Ube Industries, Ltd.) Allyl chloride (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) 2-chloromethyloxirane (manufactured by Osaka Soda Co., Ltd.) Allyl chloride (manufactured by Tokyo Chemical Industry Co., Ltd.) Sodium iodide (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) Potassium iodide (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.)

[0128]

[0129] (C) Thermal cationic polymerization initiator: Dibenzylmethyl-p-hydroxyphenylsulfonium hexafluoroantimonate (manufactured by Sanshin Chemical Industry Co., Ltd., "Sanaid SI-100L (trade name)")

[0130] The methods for measuring viscosity, modulus of elasticity, loss tangent, flexural modulus, and flexural strength, which are evaluation tests employed in the examples and comparative examples, are as follows.

[0131] [Viscosity Measurement] The viscosity of the epoxy-oxetane compounds (including epoxy compounds and oxetane compounds) used in the examples and comparative examples described below was measured at 25°C using a dynamic viscoelasticity measuring device (manufactured by UBM, "Rheosol-G5000"). The smaller the viscosity value (lower the viscosity), the better the workability is judged to be when preparing the curable composition and when using the curable composition as an adhesive.

[0132] [Measurement of Elastic Modulus and Loss Tangent] The curable compositions prepared in the examples and comparative examples described below were cured at 65°C for 2 hours, and then further heated and cured at 150°C for 2 hours. The resulting cured products (test pieces: length 30 mm x width 10 mm x thickness 1 mm) were measured for storage modulus G' (MPa) and loss tangent tanδ at 25°C (frequency: 1 Hz) using a dynamic viscoelasticity measuring device (manufactured by UBM, "Rheosol-G5000") The higher the storage modulus G' (high elasticity), the more excellent the rigidity, and the lower the loss tangent tanδ, the fewer structural defects there are in the cured product, indicating the formation of a uniform three-dimensional network.

[0133] [Measurement of flexural modulus and flexural strength] The curable compositions prepared in the examples and comparative examples described below were cured at 65°C for 2 hours, and then further heated at 150°C for 2 hours. The flexural modulus (GPa) and flexural strength (MPa) of the resulting cured products (test pieces: length 80 mm x width 25 mm x thickness 1 mm) were measured in accordance with JIS K7203. A higher flexural modulus (higher elasticity) indicates better rigidity, and a higher flexural strength indicates better mechanical strength.

[0134] Synthesis of Epoxy-Oxetane Compound Represented by Chemical Formula (I-1) Synthesis Example 1 2,178 g (37,500 mmol) of allyl alcohol and 308.58 g (2,750 mmol) of potassium tert-butoxide were charged into a 5 L three-neck flask and heated to 40°C. 285.35 g (2,500 mmol) of allyl glycidyl ether was then added dropwise, followed by stirring at 60°C for 14 hours. The reaction solution was then cooled to 25°C or below, filtered to remove solids, and the filtrate was evaporated under reduced pressure. The resulting concentrate was purified by distillation to obtain 391.19 g of a bifunctional olefin compound having a hydroxyl group represented by chemical formula (II-1) as a colorless, transparent liquid (yield: 91%).

[0135]

[0136] Synthesis Example 2: A 5-L four-neck flask was charged with 344.44 g (2,000 mmol) of the colorless, transparent liquid obtained in Synthesis Example 1, 1,500 g of dimethyl sulfoxide, and 114.96 g (2,874 mmol) of sodium hydroxide. The mixture was heated to 60°C, and then 427.35 g (2,200 mmol) of 3-ethyl-3-methanesulfonyloxymethyloxetane was added dropwise thereto. The mixture was stirred at 70°C for 8 hours. The reaction mixture was then cooled to 25°C or below, the solid matter was removed, and the filtrate was extracted with 2,000 mL of ethyl acetate. The extract was then washed with 2,000 mL of water, and the organic layer was concentrated under reduced pressure. The resulting concentrate was purified by distillation to obtain 336.92 g of the olefin-oxetane compound represented by chemical formula (Ia-1) as a colorless, transparent liquid (yield: 62%).

[0137]

[0138] Synthesis Example 3: A 1 L three-neck flask was charged with 54.07 g (200.0 mmol) of the colorless, transparent liquid obtained in Synthesis Example 2, 86.29 g (500.0 mmol) of metachloroperbenzoic acid, and 500 g of chloroform, and the mixture was stirred at 30° C. for 12 hours. The reaction solution was filtered to remove solids, and the mixture was washed with 500 mL of a 10 wt % aqueous potassium carbonate solution and 500 mL of water. The organic layer was then concentrated under reduced pressure. The resulting concentrate was purified by silica gel column chromatography (ethyl acetate / hexane = 1 / 3 (volume ratio)), yielding 26.49 g of a pale yellow, transparent liquid (yield: 44%).

[0139] This pale yellow transparent liquid １ The H-NMR spectrum data was as follows: １ H-NMR (CDCl ３) δ: 4.46 (d, 2H), 4.37 (d, 2H), 3.79 (m, 2H), 3.74 (t, 2H), 3.61 (m, 5H), 3.41 (m, 2H), 3.13 (quin., 2H), 2.79 (t, 2H), 2.60 (m, 2H), 1.74 (q, 2H), 0.88 (t, 3H). The IR spectrum data of this pale yellow, transparent liquid was as shown in the chart in Figure 1. From these spectrum data, the obtained pale yellow, transparent liquid was identified as the epoxy oxetane compound represented by chemical formula (I-1).

[0140]

[0141] Synthesis of Oxetane Compound Represented by Chemical Formula (V) Synthesis Example 4 A 500 mL three-neck flask was charged with 18.42 g (200.0 mmol) of glycerin, 180.0 g of dimethyl sulfoxide, and 22.20 g (555.0 mmol) of sodium hydroxide. The mixture was heated to 60°C, and then 104.90 g (540.0 mmol) of 3-ethyl-3-methanesulfonyloxymethyloxetane was added dropwise thereto. The mixture was stirred at 70°C for 8 hours. The reaction mixture was then cooled to 25°C or below, the solid matter was removed, and the filtrate was extracted with 200 mL of ethyl acetate. The extract was then washed with 60 mL of water, and the organic layer was concentrated under reduced pressure. The resulting concentrate was purified by silica gel column chromatography (ethyl acetate / hexane = 2 / 3 (volume ratio)) to obtain 8.50 g of a colorless, transparent liquid (yield: 11%).

[0142] This colorless and transparent liquid １ The H-NMR spectrum data was as follows: １ H-NMR (CDCl ３) δ: 4.44 (d, 6H), 4.35 (d, 6H), 3.72 (s, 2H), 3.66 (quin., 1H), 3.57 (m, 6H), 3.55 (d, 2H), 1.74 (q, 6H), 0.88 (t, 9H). The IR spectrum data of this colorless, transparent liquid was as shown in the chart in Figure 2. From these spectrum data, the obtained colorless, transparent liquid was identified as an oxetane compound represented by chemical formula (V).

[0143]

[0144] Synthesis of Epoxy Oxetane Compound Represented by Chemical Formula (VIII) Synthesis Example 5 A 1-L three-neck flask was charged with 174.24 g (1,500 mmol) of 3-ethyl-3-hydroxymethyloxetane and 8.00 g (200.0 mmol) of sodium hydroxide, and the mixture was heated to 45° C. After which 114.14 g (1,000 mmol) of allyl glycidyl ether was added dropwise and the mixture was stirred for 12 hours at 50° C. The reaction solution was then cooled to 25° C. or below, extracted with 750 mL of chloroform, and washed with 500 mL of water. The organic layer was then concentrated under reduced pressure to obtain 223.4 g of the compound represented by chemical formula (VI) as a pale yellow, transparent liquid (yield: 97%).

[0145]

[0146] Synthesis Example 6: A 2 L three-neck flask was charged with 184.73 g (750.0 mmol) of the pale yellow, transparent liquid obtained in Synthesis Example 5, 750.00 g of dimethyl sulfoxide, 45.00 g (1125.0 mmol) of sodium hydroxide, and 5.62 g (37.5 mmol) of sodium iodide. The mixture was heated to 50°C, and then 86.10 g (1125.0 mmol) of allyl chloride was added dropwise. The mixture was stirred at 50°C for 8 hours. The reaction mixture was then cooled to 25°C or below, the solid matter was removed, and the filtrate was extracted with 1500 mL of ethyl acetate. The mixture was then washed with 1500 mL of water, and the organic layer was concentrated under reduced pressure. The resulting concentrate was purified by distillation to obtain 121.67 g of the compound represented by chemical formula (VII) as a colorless, transparent liquid (yield: 60%).

[0147]

[0148] Synthesis Example 7: A 500 mL three-neck flask was charged with 27.03 g (100.0 mmol) of the colorless, transparent liquid obtained in Synthesis Example 6, 43.14 g (250.0 mmol) of metachloroperbenzoic acid, and 250 g of chloroform, and the mixture was stirred at 30° C. for 12 hours. The reaction mixture was filtered to remove solids, washed with 250 mL of a 10 wt % aqueous potassium carbonate solution and 250 mL of water, and then the organic layer was concentrated under reduced pressure. The resulting concentrate was purified by silica gel column chromatography (ethyl acetate / hexane = 1 / 3 (volume ratio)), yielding 12.02 g of a pale yellow, transparent liquid (yield: 40%).

[0149] This pale yellow transparent liquid １ The H-NMR spectrum data was as follows: １ H-NMR (CDCl ３ ) δ: 4.46 (d, 2H), 4.36 (d, 2H), 3.91 (m, 1H), 3.76 (m, 2H), 3.60 (m, 7H), 3.41 (m, 1H), 3.15 (m, 2H), 2.78 (m, 2H), 2.61 (m, 2H), 1.74 (q, 2H), 0.89 (t, 3H). The IR spectrum data of this pale yellow, transparent liquid was as shown in the chart in Figure 3. From these spectrum data, the obtained pale yellow, transparent liquid was identified as an epoxy oxetane compound represented by chemical formula (VIII).

[0150]

[0151] Synthesis of Epoxy-Oxetane Compound Represented by Chemical Formula (XI) Synthesis Example 8 278.78 g (2400.0 mmol) of 3-ethyl-3-hydroxymethyloxetane and 38.40 g (960.0 mmol) of sodium hydroxide were charged into a 1 L three-neck flask and heated to 47°C. 74.02 g (800.0 mmol) of 2-chloromethyloxirane was then added dropwise, and the mixture was stirred at 60°C for 4 hours. The reaction solution was then cooled to 25°C or below, extracted with 900 mL of chloroform, washed with 500 mL of water, and the organic layer was concentrated under reduced pressure. The concentrated solution was purified by distillation to obtain 87.51 g of the compound represented by chemical formula (IX) as a colorless, transparent liquid (yield: 38%).

[0152]

[0153] Synthesis Example 9: A 300 mL three-neck flask was charged with 40.37 g (140.0 mmol) of the colorless, transparent liquid obtained in Synthesis Example 8, 8.12 g (203.0 mmol) of sodium hydroxide, and 1.16 g (7.0 mmol) of potassium iodide. The mixture was heated to 67°C, and then 13.93 g (182.0 mmol) of allyl chloride was added dropwise thereto. The mixture was stirred at 70°C for 2 hours. The reaction mixture was then cooled to 25°C or below, the solid matter was removed, and the filtrate was extracted with 80 mL of ethyl acetate. The mixture was then washed with 40 mL of water, and the organic layer was concentrated under reduced pressure to obtain 44.79 g of the compound represented by chemical formula (X) as a colorless, transparent liquid (yield: 97%).

[0154]

[0155] Synthesis Example 10: A 500 mL three-neck flask was charged with 42.70 g (130.0 mmol) of the colorless, transparent liquid obtained in Synthesis Example 9, 22.43 g (130.0 mmol) of metachloroperbenzoic acid, and 300 g of chloroform, and the mixture was stirred at 30° C. for 12 hours. The reaction solution was then filtered to remove solids, and the mixture was washed with 150 mL of a 10 wt % aqueous potassium carbonate solution and 150 mL of water. The organic layer was concentrated under reduced pressure to obtain 38.44 g of a colorless, transparent liquid (yield: 86%).

[0156] This colorless and transparent liquid １ The H-NMR spectrum data was as follows: １H-NMR (CDCl ３ ) δ: 4.44 (d, 4H), 4.35 (d, 4H), 3.89 (dd, 1H), 3.72 (quin., 1H), 3.56 (m, 9H), 3.12 (quin., 1H), 2.77 (t, 1H), 2.60 (dd, 1H), 1.72 (q, 4H), 0.87 (t, 6H). The IR spectrum data of this colorless, transparent liquid was as shown in the chart in Figure 4. From these spectrum data, the obtained colorless, transparent liquid was identified as an epoxy oxetane compound represented by chemical formula (XI).

[0157]

[0158] Synthesis Example 11: A 1-L three-necked recovery flask was charged with 49.26 g (200.0 mmol) of the pale yellow, transparent liquid obtained in Synthesis Example 5, 200.00 g of dimethyl sulfoxide, 10.40 g (260.0 mmol) of sodium hydroxide, and 1.50 g (10.0 mmol) of sodium iodide. The mixture was heated to 50°C, and then 50.51 g (260.0 mmol) of 3-ethyl-3-methanesulfonyloxymethyloxetane was added dropwise. The mixture was stirred at 50°C for 8 hours. The reaction mixture was then cooled to 25°C or below, the solid matter was removed, and the filtrate was extracted with 400 mL of ethyl acetate. The extract was then washed with 400 mL of water, and the organic layer was concentrated under reduced pressure. The resulting concentrate was purified by distillation to obtain 26.32 g of the compound represented by chemical formula (XII) as a colorless, transparent liquid (yield: 40%).

[0159]

[0160] Synthesis Example 12: A 1-L three-necked recovery flask was charged with 26.28 g (80.0 mmol) of the colorless, transparent liquid obtained in Synthesis Example 11, 16.57 g (96.0 mmol) of metachloroperbenzoic acid, and 500 g of chloroform, and the mixture was stirred at 30°C for 12 hours. The reaction mixture was filtered to remove solids, and the mixture was washed with 100 mL of a 10 wt% aqueous potassium carbonate solution and 100 mL of water. The organic layer was then concentrated under reduced pressure. The resulting concentrate was purified by silica gel column chromatography (ethyl acetate / hexane = 2 / 3 (volume ratio)) to obtain 17.05 g of a pale yellow, transparent liquid (yield: 62%).

[0161] This pale yellow transparent liquid １ The H-NMR spectrum data was as follows: １ H-NMR (CDCl ３ ) δ: 4.43 (d, 4H), 4.32 (d, 4H), 3.77 (dd, 1H), 3.72 (d, 2H), 3.56 (m, 7H), 3.39 (m, 1H), 3.12 (quin., 1H), 2.78 (t, 1H), 2.59 (dd, 1H), 1.72 (q, 4H), 0.87 (t, 6H). The IR spectrum data of this pale yellow, transparent liquid was as shown in the chart in Figure 5. From these spectrum data, the obtained pale yellow, transparent liquid was identified as an epoxy oxetane compound represented by chemical formula (XIII).

[0162]

[0163] <Evaluation of Cured Product> [Example 1] A curable composition was prepared by uniformly mixing 100 parts by weight of the epoxy oxetane compound represented by chemical formula (I-1) synthesized in Synthesis Example 3 and 0.2 parts by weight of a thermal cationic polymerization initiator. The above-mentioned evaluation tests were carried out on this curable composition and a cured product obtained by curing the curable composition, and the obtained test results are shown in Table 1.

[0164] Comparative Examples 1 to 5 In the same manner as in Example 1, curable compositions having the formulations shown in Table 1 were prepared, and the above-mentioned evaluation tests were carried out on these curable compositions and cured products obtained by curing the curable compositions. The test results obtained are as shown in Table 1.

[0165]

[0166] Table 1 confirms that the epoxy-oxetane compound contained in the curable composition according to one embodiment of the present invention has an extremely low viscosity, and therefore provides excellent workability during preparation and use as a curable adhesive. Furthermore, the curable composition according to one embodiment of the present invention exhibits crosslinking function, and thus a cured product is obtained upon curing. Despite the low viscosity, the cured product exhibits high values ​​for storage modulus G' and flexural modulus, and also exhibits high flexural strength, confirming that the cured product has excellent mechanical strength. The cured product obtained by curing the curable composition according to one embodiment of the present invention exhibits a small value for loss tangent tanδ, suggesting that the cured product has few structural defects and forms a uniform three-dimensional network.

[0167] According to the curable composition of the present invention, it is possible to provide a curable composition and a cured product thereof that have, compared to conventional curable compositions, excellent curability, low viscosity, and mechanical strength, and the industrial applicability of the present invention is great.

Claims

1. A curable composition containing an epoxy oxetane compound represented by formula (I): (In the formula, R may be the same or different and represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms.) 2. The curable composition according to claim 1, which contains a cationic polymerization initiator.

3. A cured product obtained by curing the curable composition according to any one of claims 1 to 2.

4. An adhesive comprising the curable composition according to any one of claims 1 to 2.

5. A sealant comprising the curable composition according to any one of claims 1 to 2.

Images