JP5109324B2 - Photocurable composition for sealant, liquid crystal sealant, and liquid crystal panel - Google Patents

Description

  The present invention relates to a photocurable composition used for sealing and sealing of a panel such as a liquid crystal panel, an organic EL display panel, and electronic paper, and the like, and a liquid crystal sealant comprising the photocurable composition and the liquid crystal sealant It relates to a liquid crystal panel using.

In general, a liquid crystal panel is configured such that a rear substrate including a thin film transistor, a pixel electrode, an alignment film, and the like is opposed to a front substrate including a color filter, an electrode, an alignment film, and the like, and liquid crystal is sealed between the two substrates. A sealing agent is used for the purpose of bonding the two substrates.
In recent years, for the purpose of reducing the thickness and weight of a liquid crystal panel or imparting flexibility, it has been studied to replace the material of both the front substrate and the front and rear substrates from conventional glass to plastic. However, most of the conventionally used sealing agents have been developed for glass, and it has been difficult to divert as they are.

In general, a panel plastic substrate having a heat resistance of 200 ° C. or higher is used in consideration of a liquid crystal annealing process. However, since the coefficient of thermal expansion is larger than that of glass, during heating, expansion and contraction larger than that of glass occur.
When a thermosetting sealant composed mainly of an epoxy-based thermosetting resin is used, it is often cured at 150 degrees, but substrates with different temperature differences between the upper and lower substrates or different thermal expansion coefficients are attached to each other. When combined, there is a problem that the liquid crystal panel bends when the panel is cooled to room temperature. In order to avoid this, a method of adding a curing catalyst such as an inorganic solid acid such as silica or an organic acid such as salicylic acid to an epoxy resin and performing a curing reaction at a low temperature of 40 ° C. or less (for example, patent) However, it takes a long time to cure and is not practical.

On the other hand, a photocurable sealant mainly composed of acrylate or the like (for example, see Patent Document 2) is suitable for plastic substrates because it does not require heat for curing and can be cured in a short time. However, since acrylate has a large cure shrinkage, its adhesiveness is weak and it may be peeled off by a simple impact or the like. Also known is a photo-thermosetting sealant that uses a photo-curing component and a thermo-curing component together, first semi-cured by photo-curing, and then fully cured by heating (usually using heating during annealing). (For example, Patent Documents 3 to 6) After all, the adhesiveness to the plastic substrate was weak and there was a problem in practical use.
JP-A-11-153800 JP 2005-171135 A JP-A-5-295087 JP 2005-18022 A JP 2006-23582 A Japanese Patent Laid-Open No. 3-188186

  The problem to be solved by the present invention is to provide a photocurable composition for sealing, which has excellent electrical properties and adhesiveness, and in particular, has excellent adhesiveness to a liquid crystal cell substrate made of plastic. There is. Furthermore, it is providing the photocurable composition for a seal | sticker which can maintain the outstanding adhesiveness to the board | substrate for liquid crystal cells, even when it combines materials with a large thermal expansion coefficient difference like plastic and glass.

  The present inventors are a curable compound having both a (meth) acryloyl group and an epoxy group in one molecule, and a curable compound in which a (meth) acryloyl group and an epoxy group are introduced into a specific part of the compound. By using a compound, it has been found that a sealing agent having excellent electrical properties and adhesiveness can be obtained, and by further using the compound in combination with a photo radical curing system and a photo cation curing system, such as plastic and glass, It has been found that even when materials having a large difference in thermal expansion coefficient are combined, excellent adhesion to the liquid crystal cell substrate can be maintained, and the above problems have been solved.

  That is, this invention provides the curable composition for liquid-crystal sealing compounds containing the compound shown by General formula (1) which has the number average molecular weights in the range of 500-10000.

(In General Formula (1), X ¹ and X ² each independently represent an aliphatic hydrocarbon group having 1 to 6 carbon atoms, and Y represents a (meth) acryloyl group or a hydrogen atom (however, in one molecule At least one of Y present in the group is a (meth) acryloyl group), R ^{1 to} R ⁴ are each independently a group composed of a divalent monocyclic saturated hydrocarbon having 3 to 12 carbon atoms, A group composed of a divalent monocyclic unsaturated hydrocarbon having 5 to 12 carbon atoms, a group composed of a divalent condensed polycyclic hydrocarbon having 7 to 16 carbon atoms or a divalent carbon atom having 6 to 18 carbon atoms And t represents a repeating unit.

  Moreover, this invention provides the liquid-crystal sealing compound which uses the photocurable composition for sealing agents of the said description.

  The present invention also provides a liquid crystal panel using the liquid crystal sealant described above.

  According to the present invention, materials having excellent electrical properties and adhesiveness, particularly excellent adhesion to a liquid crystal cell substrate made of plastic, and materials having a large difference in thermal expansion coefficient such as plastic and glass are combined. In this case, a liquid crystal sealing agent that can maintain excellent adhesion to the liquid crystal cell substrate can be obtained.

(Compound represented by the general formula (1))
In the general formula (1), X ¹ and X ² each independently represent an aliphatic hydrocarbon group having 1 to 6 carbon atoms. Specific examples include a methylene group, a propylene group, an n-butylene group, and a 2,2-propanediyl group. Of these, a methylene group and a 2,2-propanediyl group are preferable.

  In the general formula (1), Y represents a (meth) acryloyl group or a hydrogen atom. However, at least one of Y present in one molecule is a (meth) acryloyl group.

In the general formula (1), R ^{1 to} R ⁴ are each independently a group composed of a monovalent saturated hydrocarbon having 3 to 12 carbon atoms and a divalent carbon having 5 to 12 carbon atoms. A group consisting of a cyclic unsaturated hydrocarbon, a group consisting of a divalent condensed polycyclic hydrocarbon having 7 to 16 carbon atoms, or a group consisting of a divalent ring assembly hydrocarbon having 6 to 18 carbon atoms. .
There is no particular limitation on the binding site of each ring. Hereinafter, for the specific name of each group, “divalent” and “group consisting of” are omitted, and only the ring name is represented.

Specific examples of the ring name of the group consisting of a divalent monocyclic saturated hydrocarbon having 3 to 12 carbon atoms include, for example, a cyclopropane ring, a cyclobutane ring group, a cyclopentane ring, a cyclohexane ring, a cycloheptane ring, a cyclo Examples include an octane ring, a cyclononane ring, a cyclodecane ring, and a cyclododecane ring.
Specific examples of the ring name of the group consisting of a divalent monocyclic unsaturated hydrocarbon having 5 to 12 carbon atoms include, for example, a cyclopentene ring, cyclohexene ring, cyclohexadiyne ring, benzene ring, cycloheptene ring, cyclohepta Examples thereof include a diyne ring, a cyclooctene ring, a cyclooctadiene ring, and a cyclododecatriene ring.

  The group consisting of a divalent condensed polycyclic hydrocarbon having 7 to 16 carbon atoms is specifically a group consisting of a hydrocarbon ring in which two or more hydrocarbon rings having 3 or more carbon atoms are condensed. Represents. Specific ring names include, for example, norbornene ring, dicyclohexane ring, dicycloheptane ring, dicyclooctane ring, dicyclononane ring, dicyclodecane ring, dicycloundecane ring, dicyclododecane ring, tricyclodecane ring, tricycloundecane A ring, a tricyclododecane ring, a tricyclotetradecane ring, a tricyclopentadecane ring, a tricyclohexadecane ring, an adamantane ring, a dihydronaphthalene ring, a tetrahydronaphthalene ring, a 9,10-dihydroanthracene ring, a naphthalene ring, and an anthracene ring.

  Specifically, the group consisting of a divalent carbon ring having 6 to 18 carbon atoms is a monocyclic hydrocarbon directly connected by a single or double bond, and the number of bonds is the number of rings. Represents a group consisting of one less hydrocarbon. Specific examples of the ring name include 1,1′-bicyclopropane ring, biphenyl ring, terphenyl ring, tercyclohexane ring, phenylcyclohexane ring, and phenylnaphthalene ring.

R ^{1 to} R ⁴ are, among others, a cohesive force is obtained by utilizing the interaction between aromatic rings, which is advantageous for adhesion. Therefore, the divalent monocyclic unsaturated group having 5 to 12 carbon atoms. A group consisting of hydrocarbon, a group having an aromatic group among groups consisting of a divalent condensed polycyclic hydrocarbon, or an aromatic group among groups consisting of a divalent ring assembly hydrocarbon having 6 to 18 carbon atoms A group having
Specific ring names include benzene ring, dihydronaphthalene ring, tetrahydronaphthalene ring, 9,10-dihydroanthracene ring, naphthalene ring, anthracene ring, biphenyl ring, terphenyl ring, phenylcyclohexane ring, or phenylnaphthalene ring. Can be mentioned.

  Among them, from the viewpoint of efficient use of ultraviolet rays used for curing, a group composed of a divalent benzene ring, a group composed of a divalent dihydronaphthalene ring, a group composed of a divalent tetrahydronaphthalene ring, a divalent 9,10- A group consisting of a dihydroanthracene ring, a group consisting of a divalent naphthalene ring, a group consisting of a divalent anthracene ring, a group consisting of a divalent biphenyl ring, a group consisting of a divalent terphenyl ring, a divalent phenylcyclohexane ring Or a divalent phenylnaphthalene ring is preferred, and a benzene ring or a biphenyl ring is more preferred from the viewpoint of solubility.

  In the general formula (1), t represents a repeating unit.

In the general formula (1), X ¹ and X ² are 2,2-propanediyl groups, R ^{1 to} R ⁴ are groups composed of a divalent benzene ring, and Y is a (meth) acryloyl group or A compound that is a hydrogen atom and has 1.5 to 6.0 (meth) acryloyl groups in one molecule is particularly preferable because it exhibits excellent properties such as adhesion to a plastic substrate, water vapor barrier properties, and electrical properties.

  The molecular weight of the compound represented by the general formula (1) is preferably in the range of 500 to 10,000 in terms of number average molecular weight (hereinafter, the number average molecular weight is abbreviated as Mn). By setting Mn to 500 or more, there is almost no elution into the liquid crystal composition when used as a sealant for a liquid crystal panel, so that a liquid crystal panel having excellent electrical characteristics can be obtained. Moreover, it is preferable for Mn to be 10,000 or less because it is excellent in solubility with other general-purpose monomer components used for viscosity adjustment purposes.

  Moreover, the amount of (meth) acryloyl groups per molecule of the compound represented by the general formula (1) is not particularly limited. However, when the number of (meth) acryloyl groups is low, the crosslinking density between (meth) acryloyl groups is low. It becomes difficult to make it high molecular weight too much, and an electrical property may be affected. Therefore, the number of (meth) acryloyl groups per molecule is preferably 1.5 to 6.0. By setting it as this range, it is possible to obtain a sealant having a good balance between the electrical properties and the adhesiveness of the liquid crystal derived from the crosslinking density. More preferably, it is the range of 2.5-6.0 pieces.

  In the present invention, since an epoxy group and an acryloyl group coexist and each molecule has an epoxy group equivalent to 2 moles, both low curing shrinkage due to photocuring of the epoxy group and rapid curing of the (meth) acryloyl group. Thus, a liquid crystal sealant having a good balance between the electrical properties and the adhesiveness of the liquid crystal can be obtained.

  The compound represented by the general formula (1) can be synthesized by a known method. As an example of the synthesis, for example, it can be obtained by reacting an epoxy resin having a secondary hydroxyl group with ethyl (meth) acryloate using a reaction catalyst such as hexamethyl-1.5-dichlorotristanoxane.

  The compound represented by the general formula (1) is preferably used in a range of 5 to 30% by mass with respect to the total amount of the curable composition for a liquid crystal sealant of the present invention, and more preferably in a range of 10 to 25% by mass. It is particularly preferable to use in If the amount of the compound is less than 5%, it is difficult to develop a sealing property such as adhesiveness. If the amount exceeds 30%, the solubility with a monomer described later used for viscosity adjustment tends to be inferior.

(Other components Photopolymerization initiator)
In the photocurable composition for a liquid crystal panel seal of the present invention, an epoxy group and a (meth) acryloyl group coexist in the composition, and upon irradiation with light, the epoxy group is cationically polymerized, and the (meth) acryloyl group is It is cured by radical polymerization and can be firmly bonded to the substrate. In order to advance polymerization more efficiently during curing, a cationic photopolymerization initiator that cationically polymerizes an epoxy group and a radical photopolymerization initiator that radically polymerizes a (meth) acryloyl group are used in the photocurable composition. It is preferable to do this.

Examples of the cationic photopolymerization initiator include onium salts such as aromatic diazonium salts, aromatic iodonium salts, and aromatic sulfonium salts. When the cationic photopolymerization initiator is used, the preferable lower limit of the wavelength range of the irradiated light is 300 nm, and the preferable upper limit is 420 nm.
Among these onium salts commercially available, for example, optomer SP-150, optomer SP-151, optomer SP-170, optomer SP-171 (all manufactured by Asahi Denka Kogyo Co., Ltd.), UVE-1014 (general) Electronics Co., Ltd.), Irgacure-261 (Ciba Geigy), Sun-Aid SI-60L, Sun-Aid SI-80L, UVI-6990 (Union Carbide), BBI-103, MPI-103, TPS-103, MDS-103, DTS-103, NAT-103, NDS-103 (all manufactured by Midori Chemical Co., Ltd.), Sun-Aid SI-100L (all manufactured by Sanshin Chemical Industry Co., Ltd.), CI-2064, CI-2639, CI-2624, CI-2481 (Both made by Nippon Soda Co., Ltd.), RHODORSIL P Examples include HOTOINITIATOR 2074 (Rhone-Poulenc), CD-1012 (Sartomer). Among these, optomer SP-150 is more preferable because it hardly causes electrode corrosion due to an onium salt and can easily obtain effective curability.

  The cationic photopolymerization initiators may be used alone or in combination of two or more. Moreover, you may use together sensitizers, such as anthracene type and a thioxanthone type, as needed. Moreover, it is although it does not specifically limit as a compounding ratio of this cationic photoinitiator, A preferable minimum is 0.1 mass part with respect to 100 mass parts of curable compositions mentioned later, and a preferable upper limit is 10 mass parts. If the amount is less than 0.1 parts by mass, the curability of the sealing agent of the present invention may be insufficient. If the amount exceeds 10 parts by mass, a large amount of cationic photopolymerization initiator that cannot be reacted remains, and the liquid crystal There is a possibility of melting out. A more preferred lower limit is 0.3 parts by mass, and a more preferred upper limit is 3 parts by mass.

Examples of radical photopolymerization initiators that can be used include benzophenone, 2,2-diethoxyacetophenone, benzyl, benzoyl isopropyl ether, benzyl dimethyl ketal, 1-hydroxycyclohexyl phenyl ketone, and thioxanthone. These radical photopolymerization initiators may be used alone or in combination of two or more.
A maleimide compound having photoinitiating ability can also be used. Specific examples of the maleimide compound having photoinitiating ability include maleimide compounds described in JP-A Nos. 2000-19868 and 2004-070297.

  The radical photopolymerization initiators may be used alone or in combination of two or more. Moreover, it is although it does not specifically limit as a mixture ratio of this radical polymerization initiator, A preferable minimum is 0.1 mass part with respect to 100 mass parts of curable compositions, and a preferable upper limit is 20 mass parts. If it is less than 0.1 parts by mass, the curability of the sealing agent of the present invention may be insufficient. If it exceeds 10 parts by mass, a large amount of radical photopolymerization initiator that cannot be reacted remains, and the liquid crystal There is a possibility of melting out. A more preferred lower limit is 0.3 parts by mass, and a more preferred upper limit is 10 parts by mass.

(Other components, radical polymerizable compounds and / or cationic polymerizable compounds)
The photocurable composition for liquid crystal panel seals of the present invention may contain a radical polymerizable compound and / or a cationic polymerizable compound for the purpose of adjusting viscosity or adhesiveness. A compound having both radically polymerizable groups and cationically polymerizable groups can also be used.
These polymerizable compounds can use general-purpose monomers.

  The radical polymerizable compound is not particularly limited as long as it is a known and commonly used compound having a (meth) acryloyl group that is generally used in the field of UV curing, but when used for a liquid crystal panel seal, Those that are difficult to mix with liquid crystal can be used more preferably. However, in order to avoid excessive curing shrinkage, it is preferable to use only a small amount of (meth) acrylate such as dipentaerythritol penta, hexaacrylate, pentaerythritol tetraacrylate and the like, which are considered to have large curing shrinkage. Moreover, since the radically polymerizable compound which has a carboxylic acid group may react with an epoxy group during storage and may increase the viscosity of the composition rapidly, it is preferable to use only a small amount.

  Modified with polyester (meth) acrylate, epichlorohydrin, which is called “photopolymerizable oligomer” in the field of UV curing, has an ester bond in the main chain structure and has at least two (meth) acryloyl groups Epoxy (meth) acrylate, ethyl oxide, propylene oxide, (meth) acrylate modified with cyclic lactone, and the like obtained in this manner can also be preferably used. However, when an acrylate having a urethane group is used in combination with a cationic curing system, curing inhibition by the urethane group occurs, so it is preferable to use only a small amount.

  Specific examples of (meth) acrylate used in the present invention include, for example, glycerin monomethacrylate (trade name “Blenmer GLM” manufactured by NOF Corporation), acroyloxyethyl phthalate (trade name “HOA-” manufactured by Kyoeisha Chemical Co., Ltd.). MPE ”), benzyl (meth) acrylate (trade name“ Biscoat # 160 ”manufactured by Osaka Organic Chemical Co., Ltd.), nonylphenoxypolyethylene glycol acrylate (trade names“ Aronix M111 ”,“ Aronix M113 ”,“ Aronix manufactured by Toagosei Co., Ltd. ” M117 "), ECH-modified phenoxy acrylate (trade name" Aronix M5700 "manufactured by Toa Gosei Co., Ltd.), EO-modified oxalic acid acrylate (trade name" HOA-MS "manufactured by Kyoeisha Chemical Co., Ltd.), EO-modified phosphate methacrylate (Kyoeisha Chemical Co., Ltd.) Product name “P-1M”) (Meth) acrylate having one (meth) acryloyl group, bis (acryloylethyl) hydroxyethyl isocyanurate (manufactured by Toa Gosei Co., Ltd.) such as rosin-modified epoxy acrylate (trade name “Beamset 101” manufactured by Arakawa Chemical Co., Ltd.) Product name “Aronix M215”), EO-modified bisphenol A diacrylate (trade name “ADPE-150” manufactured by NOF Corporation), PO-modified bisphenol A diacrylate (trade name “ADBP-200” manufactured by NOF Corporation), ECH-modified bisphenol A acrylate (trade name “Diclite UE8200” manufactured by Dainippon Ink and Chemicals), ECH-modified phthalic acid diacrylate (trade name “DA-721” manufactured by Nagase Kasei Co., Ltd.), ECH-modified hexahydrophthalic acid di Acrylate (trade name “Nagase Kasei” DA-722 "), tricyclodecane dimethanol diacrylate (trade name" IRR214 "manufactured by Daicel UCB), rosin modified ester acrylate (trade name" Beamset 115B "manufactured by Arakawa Chemical Co., Ltd.), EO modified diphosphate diphosphate. Methacrylate (trade name “P-2M” manufactured by Kyoeisha Chemical Co., Ltd.), tris (acroyloxyethyl) isocyanurate (trade name “Aronix M315” manufactured by Toa Gosei Co., Ltd.), dimethylolpropane tetraacrylate (manufactured by Toa Gosei Co., Ltd.) Trade name “Aronix M408”), dipentaerythritol hexaacrylate (trade name “Kayarad DPHA” manufactured by Nippon Kayaku Co., Ltd.), caprolactone-modified dipentaerythritol hexaacrylate (trade name “Kayarad DPCA—made by Nippon Kayaku Co., Ltd.”) 30 "," Kayarad DPCA-1 0 "), such as, having two or more (meth) acryloyl group-containing (meth) acrylate.

  In particular, among the above radical polymerizable compounds, (meth) acrylate modified with lactone and (meth) acrylate modified with rosin are used in combination with the compound represented by the general formula (1) for the purpose of TFT protection. This is particularly preferable because it makes the adhesion to the acrylic flattening film used in the above method advantageous. Specifically, lactone-modified hydroxypivalate neopentyl glycol diacrylate (trade name “HX620” manufactured by Nippon Kayaku Co., Ltd.), lactone-modified BPA epoxy phthalate ester diacrylate (trade name “Evecryl 3708” manufactured by Daicel Cytec Co., Ltd.) ), Rosin-modified epoxy acrylate (trade name “Beamset 101” manufactured by Arakawa Chemical Co., Ltd.) and the like.

  If the usage-amount of the said (meth) acrylate is a range which does not impair the range of this invention, there will be no limitation in particular. Specifically, it is preferably in the range of 20 to 70%.

  The cationically polymerizable compound is not particularly limited as long as it is a known and commonly used compound having an epoxy group, an oxetanyl group, and a vinyl ether group, which are generally used in the field of UV curing, like the radically polymerizable compound. However, a compound having an oxetanyl group is preferably used only in a small amount because it is disadvantageous in adhesiveness to plastic because the amount of hydroxyl group produced by polymerization is small.

  Examples of the cationically polymerizable compound having one or more epoxy groups in one molecule include bisphenol A type epoxy resins (trade names “Epicron 850CRP”, “Epicron 850S”, “Epicron 1050”, manufactured by Dainippon Ink, Inc. “Epicron 1055”), bisphenol F type epoxy resin (trade names “Epicron 830CRP” and “Epicron 830” manufactured by Dainippon Ink, Inc.), bisphenol S type epoxy resin (trade name “Epicron EXA1514” manufactured by Dainippon Ink, Inc.), Hydrogenated bisphenol-type epoxy resin (trade name “Epiclon EXA7015” manufactured by Dainippon Ink, Inc.), propylene oxide-added bisphenol A-type epoxy resin (trade name “EP-4000S” manufactured by Asahi Denka Co., Ltd.), resorcinol-type epoxy resin (Nagase) Made by Chemtex Trade name “EX-201”), biphenyl type epoxy resin (trade name “Epicoat YX-4000H” manufactured by Japan Epoxy Resin Co., Ltd.), dicyclopentadiene type epoxy resin (trade name “EP-4088S” manufactured by Asahi Denka Co., Ltd.) , Naphthalene type epoxy resins (trade names “Epicron HP4032” and “Epicron EXA-4700” manufactured by Dainippon Ink Co., Ltd.), phenol novolac type epoxy resins (trade names “Epicron N-770” manufactured by Dainippon Ink Co., Ltd.), ortho-cresol Biphenyl novolac type epoxy resin such as novolak type epoxy resin (trade name “Epicron N-670-EXP-S” manufactured by Dainippon Ink and Co., Ltd.), NC-3000P (manufactured by Nippon Kayaku Co., Ltd.), ESN-165S (Tohto Kasei Co., Ltd.) Naphthalene phenol novolac type epoxy resin, Epicor 630 (manufactured by Japan Epoxy Resin), rubber-modified epoxy resin (trade name “PB3600” manufactured by Daicel Chemical Industries), bisphenol A type episulfide resin (trade name “Epicoat YL-7000” manufactured by Japan Epoxy Resin) And cycloaliphatic epoxy resins (trade names “Celoxide 2021”, “Celoxide 2080”, “Celoxide 3000”, “EHPE” manufactured by Daicel Chemical Industries, Ltd.) and the like.

  Commercially available products of the cationically polymerizable compound having one or more vinyl ether groups include 4-vinyloxybutanol (trade name “Vinyl-4-hydroxybutyether” manufactured by BASF), triethylene glycol divinyl ether (manufactured by ISP). Trade name “Rapi-Cure DVE-3”), 1,4-cyclohexanedimethanol divinyl ether (trade name “CHDVE” manufactured by Nippon Carbide Industries, Ltd.) and the like.

  Examples of the cationically polymerizable compound having one or more oxetanyl groups in one molecule include 3-ethyl-3- (phenoxymethyl) oxetane (trade name “OXT-211” manufactured by Toagosei Co., Ltd.), 3-ethyl -3- (cyclohexyl) methyloxetane (trade name “CHOX” manufactured by Toagosei Co., Ltd.) and the like. Examples of the compound having two or more oxetane rings include 1,4-bis [{(3-ethyloxetane-1-yl) methoxy} methyl] benzene (trade name “OXT-121” manufactured by Toagosei Co., Ltd.), 1,3 -Bis [(3-ethyloxetane-3yl) methoxy] benzene (trade name “OXT-223” manufactured by Toa Gosei Co., Ltd.), bis [1-ethyl (3-oxetanyl)] methyl ether (product of Toa Gosei Co., Ltd.) Name “OXT-221”), phenol novolak oxetane (trade name “PNOX-1009” manufactured by Toa Gosei Co., Ltd.), 4,4′-bis [{(3-ethyloxetane-1-yl) methoxy} methyl] biphenyl (Ube) Product name “OXBP” manufactured by Kosan Co., Ltd.).

Among the cationic polymerizable compounds, a polymerizable compound having an epoxy group having an aromatic ring is particularly preferable because cohesive force is obtained by utilizing the interaction between aromatic rings, which is advantageous for adhesion. Specifically, bisphenol A type epoxy resins (trade names “Epicron 850CRP”, “Epicron 850S”, “Epicron 1050”, “Epicron 1055”, manufactured by Dainippon Ink and Co., Ltd.), bisphenol F type epoxy resins (Dainippon Ink, Inc.) Product names "Epicron 830CRP", "Epicron 830") and the like.
Since the viscosity is particularly low and the dilution effect with the compound represented by the general formula (1) is high, bisphenol A type epoxy resin (trade name “Epicron 850CRP” manufactured by Dainippon Ink, Inc.), bisphenol F type epoxy resin (large The product name “Epicron 830CRP” manufactured by Nippon Ink Co., Ltd.) is particularly preferred.

Examples of the polymerizable compound having both radical polymerizable group and cationic polymerizable group include, for example, commercially available BPF epoxy half acrylate and BPA epoxy half acrylate (trade name “UVa 1561” manufactured by Daicel Cytec Co., Ltd.) A compound obtained by reacting a part of the epoxy group of a compound having a plurality of epoxy groups in one molecule with (meth) acrylic acid to form (meth) acryloyl is mentioned.
Among these, BPA epoxy half acrylate and BPF epoxy half acrylate are more preferable because of high dilution effect with the compound represented by the general formula (1).

(Other components Silane coupling agent)
Moreover, in order to improve adhesiveness, the well-known and usual silane coupling agent can also be mixed with the photocurable composition for liquid crystal panel seals of this invention. Among such silane coupling agents, a silane coupling agent having a polymerizable group such as a (meth) acryloyl group or an epoxy group is copolymerized with the compound represented by the general formula (1) upon photocuring. In particular, it is particularly preferable because high adhesiveness can be obtained.

  Examples of the silane coupling agent having a polymerizable group include 3- (meth) acryloyloxypropyltrimethoxysilane, 3-epoxyoxypropyltrimethoxysilane, and the like. Examples of commercially available silane coupling agents having such a polymerizable group include, for example, trade names “KBM503”, “KBE503”, “KBM502”, “KBE502”, “KBM5102”, and “KBM5103” manufactured by Shin-Etsu Chemical Co., Ltd. , “KBM403” and the like.

  The amount of the silane coupling agent used in combination is preferably 0.1 to 10% by mass, particularly preferably 1 to 5% by mass, based on the total amount of the curable composition. If the ratio of the silane coupling agent is less than 0.1% by mass, a sufficient adhesion effect may not be obtained, and if it exceeds 10% by mass, phase separation may occur. A more preferred lower limit is 0.5 parts by mass, and a more preferred upper limit is 5 parts by mass.

(Other ingredients Other)
In the photocurable composition for liquid crystal panel seals of the present invention, known and commonly used additives and fillers can be appropriately added depending on the purpose such as viscosity adjustment and storage stability.

  For example, the filler is added for the purpose of improving the adhesiveness of the sealant of the present invention due to the stress dispersion effect and improving the linear expansion coefficient. For example, talc, asbestos, silica, diatomaceous earth, smectite, bentonite, calcium carbonate, magnesium carbonate, alumina, montmorillonite, diatomaceous earth, magnesium oxide, titanium oxide, magnesium hydroxide, aluminum hydroxide, glass beads, barium sulfate, gypsum, calcium silicate Inorganic fillers such as talc, glass beads, sericite activated clay, bentonite, and organic fillers such as polyester fine particles, polyurethane fine particles, vinyl polymer fine particles, and acrylic polymer fine particles.

  Although it does not specifically limit as a compounding ratio of the said filler, A preferable minimum is 1 mass part with respect to 100 mass parts of said curable compositions, and a preferable upper limit is 100 mass parts. When the amount is less than 1 part by mass, the effect of adding the filler is hardly obtained. When the amount exceeds 100 parts by mass, the handling property such as the drawability of the sealing agent of the present invention may be deteriorated. A more preferred lower limit is 5 parts by mass, and a more preferred upper limit is 50 parts by mass.

(viscosity)
When the viscosity of the photocurable composition for a liquid crystal panel seal of the present invention measured at 25 ° C. using an E-type viscometer is 100 Pa · s or more, a liquid crystal seal for producing a liquid crystal display element by a dropping method described later is used. More preferably, it can be used as an agent.
When it is less than 100 Pa · s, when the liquid crystal display element is manufactured by the dropping method, the shape of the seal pattern formed on the transparent substrate cannot be maintained, and the sealing agent component is eluted in the liquid crystal, resulting in liquid crystal contamination. May end up. A more preferred lower limit is 100 Pa · s, and a more preferred upper limit is 500 Pa · s. If it exceeds 500 Pa · s, the drawing property of the sealing agent of the present invention is not sufficient, and it may be difficult to produce a liquid crystal display element by a dropping method. In this case, the E-type viscometer for measuring the viscosity is not particularly limited, and, for example, “DV-III” manufactured by Brookfield can be used.

(Liquid crystal sealant)
The photocurable composition for sealing a liquid crystal panel according to the present invention is used as a sealing agent for preparing a liquid crystal panel, and as a sealing agent for sealing an injection port after injecting a liquid crystal material into the liquid crystal panel. Can do.

  For example, the liquid crystal panel is formed by applying the photocurable composition for sealing a liquid crystal panel of the present invention to either the front or back substrate provided with a thin film transistor, a pixel electrode, an alignment film, a color filter, an electrode, and the like. Thereafter, the other substrate is bonded, and light is irradiated from the substrate surface side or the side surface of the substrate to cure the photocurable composition for sealing a liquid crystal panel of the present invention. Next, after injecting liquid crystal into the obtained liquid crystal cell, the injection port is sealed with a sealant, whereby a liquid crystal panel can be produced.

  In addition, the liquid crystal panel is applied to the outer edge portion of either one of the substrate surfaces in the form of a frame, and the liquid crystal panel sealing photocurable composition of the present invention is applied thereto. It can also be produced by a method in which the other substrate is bonded and then photocured.

  In order to apply the photocurable composition for liquid crystal panel seal of the present invention to the substrate surface, a dispenser may be used or a screen printing method may be used. In that case, it is common to apply to a line width of 0.08 to 0.1 mm and a line height of 5 to 50 μm.

The light used for curing the photocurable composition for sealing a liquid crystal panel of the present invention is preferably ultraviolet light or visible light, and particularly preferably light having a wavelength of 300 nm to 400 nm. As the light source, for example, a high-pressure mercury lamp, a metal halide lamp, or the like can be used. When the illuminance of the light source is 500 W / m ² or more, it is preferable that curing is quick. If the light quantity to be irradiated is 200 J / m ² or more in terms of the integrated light quantity, it can be cured well. Further, the photocurable composition for liquid crystal panel seals of the present invention shows good photocurability even in an air atmosphere, but when photocured in an inert gas atmosphere such as nitrogen, it is cured with a small amount of accumulated light. This is more preferable.

  Hereinafter, the present invention will be specifically described with reference to Examples and Comparative Examples. “Parts” in Examples and Comparative Examples indicates “parts by mass” unless otherwise specified. In addition, evaluation about adhesiveness, a voltage retention, and water vapor | steam barrier property was performed as follows.

Synthesis Example 1 (Synthesis of reaction catalyst)
A reaction vessel equipped with a stirrer, a thermometer, and a dropping funnel was charged with 16.48 g (75 mmol) of dimethyltin dichloride, 120 ml of water and 45 ml of ethanol, and stirred to dissolve uniformly. Next, 10.1 g (100 mmol) of triethylamine was dropped from the dropping funnel under stirring. At this time, the reaction vessel was bathed in ice and the contents were kept at around 20 ° C. After completion of the dropwise addition, the reaction was further carried out by stirring at the same temperature for 3 hours. After completion of the reaction, the white precipitate was filtered, washed with 100 ml of water and then with 200 ml of ethanol, and then dried under reduced pressure at 105 ° C. to obtain hexamethyl-1.5-dichlorotristanoxane.

Synthesis Example 2 (Synthesis of Compound (A1) Represented by General Formula (1))
Synthesis of partially acrylated bisphenol A type epoxy resin (A1) A reaction flask equipped with a stirrer, an air introduction tube, a thermometer, and a fractionation column was added to a bisphenol A type epoxy resin EPICLON AM-040-P (Dainippon Ink Chemical Co., Ltd.) 10.0 g of the product, number average molecular weight Mn = 2000, polystyrene conversion value by GPC), 120.0 g of ethyl acrylate, 0.6 g of the tristanoxane compound obtained in the above synthesis example as a catalyst, and as a polymerization inhibitor 1.2 g of p-methoxyphenol was charged, and the reaction was started while introducing air. The reaction was carried out for 24 hours while removing ethanol produced at a reaction temperature of 95 to 98 ° C. as a mixed solution with ethyl acrylate.

After completion of the reaction, excess ethyl acrylate was removed by distillation under reduced pressure, and a small amount of toluene was added to the residue, followed by further distillation under reduced pressure to remove excess ethyl acrylate.
The reaction mixture left by vacuum distillation was added to 300 ml of methanol solution and the white solid produced was separated. The white solid was dissolved in a small amount of chloroform and then added again to 300 ml of methanol solution to separate the precipitated white solid. The resulting white solid was subjected to column purification using neutral alumina (300 mesh) and ethyl acetate, and then the solvent was removed under reduced pressure. Next, drying at 40 ° C. under reduced pressure gave 11.6 g of a linear acryloyl group-containing compound (A1) represented by the formula (A1) having the target bisphenol A as the main skeleton.

（Ａ１）

(A1)

As a result of measuring ¹ H-NMR (manufactured by JEOL Ltd., AL300, 300 MHz, solvent CDCl ₃ ) for the obtained compound, 6.80 to 7 in the epoxy resin raw material and product before and after the transesterification reaction. Comparison of integral ratios of .18 ppm aromatic hydrogen, 5.83 to 6.44 ppm acryloyl group hydrogen, and 2.74, 2.90, 3.33 ppm epoxy group hydrogen to secondary hydroxyl groups of epoxy resin The acryloyl group introduction rate was 99 mol% or more. The number t of repetitions in the structural formula is about 5.7 as an average value, the number average molecular weight is 2300, and the number of acryloyl groups per molecule is 5.7.

Synthesis Example 3 (Synthesis of Compound (A2) Represented by General Formula (1))
Bisphenol A type epoxy resin EPICLON AM-040-P (manufactured by Dainippon Ink & Chemicals, Inc., number average molecular weight Mn = 2000, converted to polystyrene by GPC) 10 g described in Synthesis Example 1 EPICLON 1055 (Dainippon Ink & Chemicals, Inc., number average molecular weight Mn = 1000, polystyrene converted value by GPC) was used in the same manner as in Synthesis Example 1 except that the target bisphenol A was the main skeleton. 1.6 g of linear acryloyl group-containing compound 1 (A2) represented by the formula (A2) was obtained.

As a result of measuring ¹ H-NMR (manufactured by JEOL Ltd., AL300, 300 MHz, solvent CDCl ₃ ) for the obtained compound, 6.80 to 7 in the epoxy resin raw material and product before and after the transesterification reaction. Comparison of integral ratios of .18 ppm aromatic hydrogen, 5.83 to 6.44 ppm acryloyl group hydrogen, and 2.74, 2.90, 3.33 ppm epoxy group hydrogen to secondary hydroxyl groups of epoxy resin The acryloyl group introduction rate was 99 mol% or more. The number t of repetitions in the structural formula is about 2.3 as an average value, the number average molecular weight is 1100, and the number of acryloyl groups per molecule is 2.3.

Synthesis Example 4 (Synthesis of Compound (A3) Represented by General Formula (1))
EPICLON AM-040-P 18.6 g (20 meq), ethyl acrylate 200.0 g, the above-described tristanoxane compound [theoretical structural formula ClSn (CH ₃ ) ₂ OSn (CH ₃ ) ₂ OSn (CH _3] ) ₂ Cl] (1.0 g) and p-methoxyphenol (2.0 g) as a polymerization inhibitor were charged, and the reaction was started while introducing air. Ethanol produced using a fractionation column was refluxed with a mixed solution with ethyl acrylate at a reaction temperature of 95 to 98 ° C., and the reaction was carried out while confirming the amount of deethanol. During the reaction for about 6 hours, the amount of deethanol was 1.52 g, and the reaction was completed.

  After completion of the reaction, excess ethyl acrylate was removed by distillation under reduced pressure, and a small amount of toluene was added to the residue, followed by further distillation under reduced pressure to remove excess ethyl acrylate.

  The reaction mixture subjected to the above-mentioned vacuum distillation was added to 600 ml of methanol solution, and the white solid produced was separated. The white solid was dissolved using a small amount of chloroform and then added again to 600 ml of methanol solution to separate the reprecipitated white solid. The resulting white solid was subjected to column purification using neutral alumina (300 mesh) and ethyl acetate, and then the solvent was removed under reduced pressure. Next, by drying under reduced pressure at 40 ° C., a linear acryloyl group-containing compound (A3) represented by the formula (A3) in which an acryloyl group is introduced into some hydroxyl groups of the bisphenol A type epoxy resin 22.2 g was obtained.

（Ａ３）

(A3)

(However, the structural unit having an acryloyl group in the structural formula and the structural unit having a hydroxyl group are randomly bonded.)

As a result of ¹ H-NMR measurement of the obtained compound, 6.80 to 7.18 ppm of aromatic hydrogen and 5.83 to 6.44 ppm of epoxy resin raw material and product before and after the transesterification reaction. By comparing the integration ratio of acryloyl group hydrogen and 2.74, 2.90, 3.33 ppm of epoxy group hydrogen, the introduction ratio of acryloyl group to the secondary hydroxyl group of the epoxy resin was 54 mol%. In addition, the number average molecular weight of the obtained compound is 2150, and the number of acryloyl groups per molecule is 3.1.

(Comparative synthesis example) Synthesis of partially acrylated phenol novolac type epoxy resin (B1) A phenol novolac type epoxy resin (Dainippon Ink Chemical Co., Ltd.) having an average nucleus number of 5.5 in a round flask with a reflux condenser. Product name “EPICRON N740”) 88.4 parts, acrylic acid 40.0 parts, and toluphenylphosphine as a catalyst at 2000 ppm based on the total amount, purging air at 100 ° C. The mixture was heated and stirred for 10 hours to obtain the objective partially acrylated phenol novolac type epoxy resin (B1) in which about half of the glycidyl group was acrylated.

<Adhesion test glass, acrylic coated glass>
A spherical spacer having an average particle size of about 5.5 μm—a photocurable composition for sealing a liquid crystal panel, which will be described later, to which 1% of “Hayabeads L-11S” was added in advance, and a syringe equipped with a precision nozzle having a diameter of 0.2 mm Using a desktop coating robot (trade name “SHOT MINI” manufactured by Musashi Engineering Co., Ltd.), a plastic film with a 150 × 15 mm gas barrier (SiOx) layer (trade name “manufactured by Sumitomo Bakelite Co., Ltd.”) is used. FST1300 ") was applied linearly over a length of 9 cm so as to be parallel to the major axis direction of the substrate. From the top, a non-alkali glass plate having a size of 95 × 15 mm (trade name “corning 7059” manufactured by Corning) was stacked in parallel.
Using a pressure curing device with a quartz window from EHC, pressurize for 0.1 MPa for 2 minutes, then pressurize the glass plate from the top of the glass plate through quartz in the pressure curing device in an air atmosphere. Was used for irradiation for 40 seconds with an ultraviolet ray of 500 W / m ² to obtain an evaluation sample having an adhesive width of 1 mm and an adhesive layer thickness of 5.5 μm. The bonded evaluation sample is subjected to a 90-degree peel test at a speed of 100 mm / min, the force (mN) required to break the bonded portion is evaluated, and the force per unit width (mN / mm) is large or small Evaluated by.

  In addition, the adhesion to the glass substrate coated with acrylic is an acrylic coating prepared according to Example 1 described in Japanese Patent No. 3321858 on an alkali-free glass plate (trade name “corning 7059” manufactured by Corning). The glass plate was cut into a size of 95 mm × 15 mm and used in the same manner as the evaluation of adhesion to glass except that it was used as a substitute for the glass plate substrate.

<Adhesion test glass after heating, acrylic coated glass>
Adhesiveness was evaluated according to the above adhesive test, except that the sample was heated at 120 ° C. for 30 minutes with UV maintained after UV irradiation, and then slowly cooled to obtain an evaluation sample.

<Creation of liquid crystal panel for voltage holding ratio test>
1. LCD panel production 1 (photocuring)
One glass substrate “RZ-B107N1N” with ITO manufactured by EHC was sprayed with a 5% ethanol dispersion of spacer “LH11S” manufactured by Hayakawa Rubber. Next, a photocurable composition for sealing a liquid crystal panel, which will be described later, is applied to another glass substrate with ITO using a dispenser, and a width of about 1 mm so that two liquid crystal inlets are provided on the outer edge of the substrate. After coating, the two glass substrates face each other and bonded together, and under a nitrogen atmosphere, using a high-pressure meta-harara lamp, 500 W / m ² of ultraviolet light is irradiated for 40 seconds to irradiate the two-hole cell. Produced. A TFT (thin film transistor) driving liquid crystal composition having the following composition is injected into a two-hole cell under vacuum, and the liquid crystal composition is masked so as not to be directly exposed to ultraviolet rays, and then a liquid crystal panel sealant (three bond) 2 holes were sealed with a product name “3026B” manufactured by the company, and 500 W / m ² of ultraviolet rays were re-irradiated for 40 seconds using a high-pressure meta-harara lamp under a nitrogen atmosphere to produce a liquid crystal panel.

ＴＦＴ駆動用液晶組成物の組成

Composition of liquid crystal composition for driving TFT

Physical properties of the above TFT driving liquid crystal composition Dielectric anisotropy (Δε): 5.30
Specific resistance value: 5.2 × 10 ¹⁴ Ω · m

<Voltage retention test>
The voltage holding ratio after the liquid crystal panel produced by any of the above methods was kept in a constant temperature bath at 80 ° C. for 1 hour was measured. The voltage holding ratio was calculated by applying an initial voltage of AC 5 V to the liquid crystal panel at 80 ° C. for 64 microseconds and multiplying the voltage ratio before and after the frame time of 200 milliseconds by 100.

[Example 1]
A diepoxy compound having a bisphenol A skeleton (trade name “EPICRON 850CRP” manufactured by Dainippon Ink and Chemicals, Inc.) 25 parts, an epoxy compound having a bisphenol A skeleton (trade name “EPICRON 1050” manufactured by Dainippon Ink and Chemicals, Inc. 10 Part, 20 parts of compound (A1) and 10 parts of bisphenol A type epoxy half acrylate (trade name “UVa1561” manufactured by Daicel Cytec Co., Ltd.) were dissolved at 140 ° C. Then, while stirring at 120 ° C., caprolactone-modified hydroxy Add 25 parts of pivalic acid neopentyl glycol diacrylate (trade name “KAYARAD HX620” manufactured by Nippon Kayaku Co., Ltd.) and 10 parts of rosin-modified epoxy acrylate (trade name “Beamset 101” manufactured by Arakawa Chemical Co., Ltd.) Stir until further 2,2-dimethoxy-2-phenylacetophenone (trade name “IRGACURE 651” of Ciba Specialty Chemicals) as a radical polymerization initiator and 2.5 parts of trade name “SP150” manufactured by Asahi Denka Co., Ltd. as a cationic photopolymerization initiator After stirring at 90 ° C. and uniformly dissolving, 5.0 parts of a silane coupling agent (trade name “KBM5103” from Shin-Etsu Chemical Co., Ltd.) is added and kneaded with three rolls, and light for liquid crystal panel sealing A curable composition was obtained.
About this composition, while producing the liquid crystal panel by the method of the said liquid crystal panel preparation 1, it evaluated according to the said evaluation method, The result was shown in Table 1.

[Example 2]
A photocurable composition for a liquid crystal panel seal was obtained in the same manner as described in Example 1, except that 20 parts of the compound (A2) was used instead of 20 parts of the compound (A1) in Example 1. About this composition, while producing the liquid crystal panel by the method of the said liquid crystal panel preparation 1, it evaluated according to the said evaluation method, The result was shown in Table 1.

[Example 3]
A photocurable composition for a liquid crystal panel seal was obtained in the same manner as described in Example 1, except that 20 parts of the compound (A3) was used instead of 20 parts of the compound (A1) in Example 1. About this composition, while producing the liquid crystal panel by the method of the said liquid crystal panel preparation 1, it evaluated according to the said evaluation method, The result was shown in Table 1.

[Comparative Example 1]
A photocurable composition for a liquid crystal panel seal was obtained in the same manner as described in Example 1, except that 20 parts of the compound (B1) was used instead of 20 parts of the compound (A1) in Example 1. About this composition, while producing the liquid crystal panel by the method of the said liquid crystal panel preparation 1, it evaluated according to the said evaluation method, The result was shown in Table 1.

[Comparative Example 2]
According to the same method as described in Example 1, except that 20 parts of bisphenol A type epoxy acrylate (trade name “Ebecryl 3700” manufactured by Daicel Cytec Co., Ltd.) was used instead of 20 parts of Compound (A1) in Example 1. A photocurable composition for a liquid crystal panel seal was obtained. About this composition, while producing the liquid crystal panel by the method of the said liquid crystal panel preparation 1, it evaluated according to the said evaluation method, The result was shown in Table 1.

[Comparative Example 3]
A method similar to that described in Example 1 except that 20 parts of bisphenol A type epoxy half acrylate (trade name “UVa1561” manufactured by Daicel Cytec Co., Ltd.) was used instead of 20 parts of compound (A1) in Example 1. According to the above, a photocurable composition for liquid crystal panel seal was obtained. About this composition, while producing the liquid crystal panel by the method of the said liquid crystal panel preparation 1, it evaluated according to the said evaluation method, The result was shown in Table 1.

[Comparative Example 4]
Example 1 except that 20 parts of bisphenol A type solid epoxy resin (trade name “EPICRON AM040P” manufactured by Dainippon Ink & Chemicals, Inc.) was used in place of 20 parts of compound (A1) in Example 1. According to the same method as described in 1, a photocurable composition for a liquid crystal panel seal was obtained. About this composition, while producing the liquid crystal panel by the method of the said liquid crystal panel preparation 1, it evaluated according to the said evaluation method, The result was shown in Table 1.

[Comparative Example 5]
Instead of 20 parts of the compound (A1) in Example 1, 20 parts of a phenol novolac type epoxy resin (trade name “EPICRON N740” manufactured by Dainippon Ink & Chemicals, Inc.) was used. A photocurable composition for a liquid crystal panel seal was obtained according to the same method as described. About this composition, while producing the liquid crystal panel by the method of the said liquid crystal panel preparation 1, it evaluated according to the said evaluation method, The result was shown in Table 1.

From the result shown in Table 1, the composition of each Example 1-3 is excellent in the adhesiveness with respect to a plastic film and glass, a plastic film, and an acrylic coat glass substrate, and is excellent also in the voltage holding rate.
Comparative Example 1 is a novolak type epoxy half acrylate, Comparative Examples 2 and 3 are lower molecular weights than those of Examples, or a system in which no epoxy group remains, and Comparative Examples 4 and 5 are epoxy resins having no acrylic group. These were all poor in adhesion.

Claims (6)

A curable composition for a liquid crystal sealant containing a compound represented by the general formula (1) having a number average molecular weight in the range of 500 to 10,000,
Y in the general formula (1) is a (meth) acryloyl group having 2.3 to 5.7 in one molecule of the compound represented by the general formula (1). Composition.

(In General Formula (1), X ¹ and X ² each independently represent an aliphatic hydrocarbon group having 1 to 6 carbon atoms, and R ^{1 to} R ⁴ each independently represent the number of divalent carbon atoms. A group consisting of 3-12 monocyclic saturated hydrocarbons, a divalent monocyclic unsaturated hydrocarbon group having 5-12 carbon atoms, a divalent condensed polycyclic carbon atom having 7-16 carbon atoms A group consisting of hydrogen or a group consisting of a divalent ring-assembled hydrocarbon having 6 to 18 carbon atoms is represented, and t represents a repeating unit.) In the general formula (1), R ^{1 to} R ⁴ are each independently a group composed of a divalent benzene ring, a group composed of a divalent dihydronaphthalene ring, a group composed of a divalent tetrahydronaphthalene ring, or a divalent group. A group consisting of a 9,10-dihydroanthracene ring, a group consisting of a divalent naphthalene ring, a group consisting of a divalent anthracene ring, a group consisting of a divalent biphenyl ring, a group consisting of a divalent terphenyl ring, 2 The liquid crystal sealant curable composition according to claim 1, which is a group consisting of a divalent phenylcyclohexane ring or a group consisting of a divalent phenylnaphthalene ring. In the general formula (1), X ¹ and X ² are a methylene group, a propylene group, an n-butylene group or a 2,2-propanediyl group, and R ^{1 to} R ⁴ are groups composed of a divalent benzene ring. The liquid-crystal sealing compound curable composition of Claim 1 or 2. The sealing agent composition for photocurable liquid crystal panels in any one of Claims 1-3 containing a cationic photoinitiator and a radical photoinitiator. A liquid crystal sealant comprising the photocurable composition for a sealant according to any one of claims 1 to 4. A liquid crystal panel comprising the liquid crystal sealant according to claim 5.