Use of a sealant for liquid crystal display elements, and a curable resin composition as a sealant for liquid crystal display elements.

Abstract

The present invention aims to provide a sealant for liquid crystal display elements that exhibits excellent high-temperature adhesion, moisture permeability prevention, and low liquid crystal contamination. Furthermore, the present invention aims to provide a method for using a curable resin composition as a sealant for liquid crystal display elements. The present invention relates to a sealant for liquid crystal display elements comprising a curable resin, a photoradical polymerization initiator, and a thermosetting agent, wherein the curable resin comprises a (meth)acrylic compound without epoxy groups and an epoxy compound, and the (meth)acrylic compound comprises a polyfunctional (meth)acrylic compound (X1) having two or more (meth)acryloyloxy groups in one molecule, and the number of atoms constituting the shortest covalent bond connecting one (meth)acryloyloxy group to the other (meth)acryloyloxy group between the two (meth)acryloyloxy groups that are furthest apart is 1 to 6.

Description

[Technical Field]

[0001] This invention relates to a sealant for liquid crystal display elements. Furthermore, this invention relates to the use of a curable resin composition as a sealant for said liquid crystal display elements. [Background technology]

[0002] As a method for manufacturing liquid crystal elements, a liquid crystal dropping method called the dropping method, which uses a photothermosetting sealant containing a curable resin, a photopolymerization initiator, and a thermosetting agent, is used, from the viewpoint of shortening the cycle time and optimizing the amount of liquid crystal used, as disclosed in Patent Documents 1 and 2. In the drop-type method, a rectangular sealing pattern is first formed on one of two electrode-equipped substrates by dispensing. Next, while the sealant is still uncured, tiny droplets of liquid crystal are dropped into the sealing frame of the substrate, and the other substrate is placed on top under vacuum. The sealed area is then irradiated with light such as ultraviolet to perform partial curing. After that, heating is performed to perform full curing and fabricate the liquid crystal element.

[0003] By the way, in today's world where various mobile devices with LCD panels, such as mobile phones and portable game consoles, are widespread, miniaturization of these devices is the most pressing issue. One method of miniaturizing devices is to narrow the bezel of the LCD display, for example, by placing the sticker area below the black matrix (hereinafter also referred to as narrow bezel design). [Prior art documents] [Patent Documents]

[0004] [Patent Document 1] Japanese Patent Publication No. 2001-133794 [Patent Document 2] International Publication No. 02 / 092718 [Overview of the project] [Problems that the invention aims to solve]

[0005] With the increasing performance of liquid crystal display elements, reliability in operation under high temperature and high humidity environments is becoming increasingly important, and sealants with excellent high-temperature adhesion and moisture-proof properties are required. One way to improve the high-temperature adhesion and moisture-proof properties of sealants is to have a high glass transition temperature after curing. To improve the glass transition temperature of the cured sealant, the use of compounds with a rigid structure such as a cross-linked structure as a curable resin has been investigated. However, when compounds with a cross-linked structure are used, there is a problem that the sealant is more likely to contaminate the liquid crystal. In particular, in recent years, with the narrow bezel design, the application width of sealants has become narrower, making it difficult to achieve excellent high-temperature adhesion, moisture-proof properties, and low liquid crystal contamination properties even with sealants that previously had no problems.

[0006] The present invention aims to provide a sealant for liquid crystal display elements that exhibits excellent high-temperature adhesion, moisture permeability prevention, and low liquid crystal contamination. Furthermore, the present invention aims to provide a method for using a curable resin composition as a sealant for liquid crystal display elements. [Means for solving the problem]

[0007] Disclosure 1 is a sealant for liquid crystal display elements comprising a curable resin, a photoradical polymerization initiator, and a thermosetting agent, wherein the curable resin comprises a (meth)acrylic compound without epoxy groups and an epoxy compound, and the (meth)acrylic compound comprises a polyfunctional (meth)acrylic compound (X1) having two or more (meth)acryloyloxy groups in one molecule, and the number of atoms constituting the shortest covalent bond connecting one (meth)acryloyloxy group to the other (meth)acryloyloxy group between the two (meth)acryloyloxy groups that are furthest apart is 1 to 6. Disclosure 2 is a sealant for liquid crystal display elements according to Disclosure 1, wherein the polyfunctional (meth)acrylic compound (X1) has 1 to 3 atoms that constitute the shortest possible covalent bond connecting one (meth)acryloyloxy group to the other (meth)acryloyloxy group between two (meth)acryloyloxy groups that are furthest apart. Disclosure 3 is a sealant for liquid crystal display elements according to Disclosure 1 or 2, wherein the polyfunctional (meth)acrylic compound (X1) has at least one hydroxyl group in one molecule. Disclosure 4 is a sealant for liquid crystal display elements according to Disclosure 3, wherein the polyfunctional (meth)acrylic compound (X1) is a compound represented by the following formula (1). Disclosure 5 is a sealant for liquid crystal display elements according to any of Disclosures 1 to 4, wherein the content of the polyfunctional (meth)acrylic compound (X1) in 100 parts by mass of the curable resin is 5 parts by mass or more and 42 parts by mass or less. Disclosure 6 is a sealant for liquid crystal display elements comprising a curable resin, a photoradical polymerization initiator, and a thermosetting agent, wherein the curable resin comprises a (meth)acrylic compound without epoxy groups and an epoxy compound, and the (meth)acrylic compound comprises a polyfunctional (meth)acrylic compound (X2) having two or more (meth)acryloyloxy groups in one molecule and having an (meth)acryloyloxy group equivalent of 130 or less. Disclosure 7 is a sealant for liquid crystal display elements according to Disclosure 6, wherein the polyfunctional (meth)acrylic compound (X2) has at least one hydroxyl group in one molecule. Disclosure 8 is a sealant for liquid crystal display elements according to Disclosure 6 or 7, wherein the polyfunctional (meth)acrylic compound (X2) is a compound represented by the following formula (2). Disclosure 9 is a sealant for liquid crystal display elements according to any of Disclosures 6 to 8, wherein the content of the polyfunctional (meth)acrylic compound (X2) in 100 parts by mass of the curable resin is 5 parts by mass or more and 42 parts by mass or less. Disclosure 10 is a sealant for liquid crystal display elements according to any of Disclosures 1 to 9, wherein the glass transition temperature of the cured product is 110°C or higher and 170°C or lower. The present disclosure 11 relates to use of a curable resin composition as a sealant for liquid crystal display elements, wherein the curable resin composition contains a curable resin, a photoradical polymerization initiator and a thermal curing agent; the curable resin contains a (meth)acrylic compound having no epoxy group and an epoxy compound; the (meth)acrylic compound contains a polyfunctional (meth)acrylic compound (X1) that has two or more (meth)acryloyloxy groups in one molecule, and wherein the number of atoms constituting the shortest covalent bond connecting one (meth)acryloyloxy group to the other (meth)acryloyloxy group between the two (meth)acryloyloxy groups at the farthest positional relationship is 1 or more and 6 or less. The present disclosure 12 relates to use of a curable resin composition as a sealant for liquid crystal display elements, wherein the curable resin composition contains a curable resin, a photoradical polymerization initiator and a thermal curing agent; the curable resin contains a (meth)acrylic compound having no epoxy group and an epoxy compound; the (meth)acrylic compound contains a polyfunctional (meth)acrylic compound (X2) that has two or more (meth)acryloyloxy groups in one molecule and has a (meth)acryloyloxy group equivalent of 130 or less.

[0008]

Chemical Formula

[0009] In formula (1), R 1 and R 2 are each independently a hydrogen atom or a methyl group, and R 3 to R 8 are each independently a hydrogen atom, an alkyl group having 1 to 3 carbon atoms, or a hydroxyl group, R 3 to R 8 at least one of which is a hydroxyl group.

[0010]

Chemical Formula

[0011] In formula (2), R 9 and R 10 are each independently a hydrogen atom or a methyl group, and R11 ~R 16 each independently represent a hydrogen atom, an alkyl group having 1 to 3 carbon atoms, or a hydroxyl group, and at least one of R 11 ~R 16 is a hydroxyl group.

[0012] The present invention is described in detail below. Hereinafter, an embodiment of the present invention or one embodiment thereof is referred to as "the present embodiment". Further, the sealant for a liquid crystal display element according to the first aspect of the present disclosure is referred to as the sealant for a liquid crystal display element of "the first embodiment", the sealant for a liquid crystal display element according to the sixth aspect of the present disclosure is referred to as the sealant for a liquid crystal display element of "the second embodiment", and matters common to the sealant for a liquid crystal display element of the first embodiment and the sealant for a liquid crystal display element of the second embodiment are described as the sealant for a liquid crystal display element of "the present embodiment".

[0013] The inventors of the present invention studied the use of a polyfunctional (meth)acrylic compound having a specific structure as the (meth)acrylic compound in a photothermally curable sealant for a liquid crystal display element containing a (meth)acrylic compound and an epoxy compound as curable resins. As a result, they found that a sealant for a liquid crystal display element excellent in high-temperature adhesiveness, moisture permeation prevention property, and low liquid crystal contamination property can be obtained, and thus completed the invention according to the first embodiment. Furthermore, the inventors of the present invention studied the use of a polyfunctional (meth)acrylic compound having a (meth)acryloyloxy group equivalent of not more than a specific value as the (meth)acrylic compound in a photothermally curable sealant for a liquid crystal display element containing a (meth)acrylic compound and an epoxy compound as curable resins. As a result, they found that a sealant for a liquid crystal display element excellent in high-temperature adhesiveness, moisture permeation prevention property, and low liquid crystal contamination property can be obtained, and thus completed the invention according to the second embodiment.

[0014] The sealant for a liquid crystal display element of the present embodiment contains a curable resin. The curable resin includes a (meth)acrylic compound having no epoxy group. In this specification, "(meth)acrylic" means acrylic or methacrylic.

[0015] In the sealant for liquid crystal display elements of this embodiment 1, the (meth)acrylic compound includes a polyfunctional (meth)acrylic compound (X1) having two or more (meth)acryloyloxy groups in one molecule, and the number of atoms constituting the shortest covalent bond connecting one (meth)acryloyloxy group to the other (meth)acryloyloxy group at the two furthest relative positions (hereinafter also referred to as "number of atoms at the shortest distance between (meth)acryloyloxy groups") is 1 or more and 6 or less. By containing the above polyfunctional (meth)acrylic compound (X1), the sealant for liquid crystal display elements of this embodiment 1 has excellent high-temperature adhesion, moisture permeability prevention, and low liquid crystal contamination. In this specification, "(meth)acryloyl" means acryloyl or methacryloyl. Furthermore, the phrase "the two (meth)acryloyloxy groups in the furthest relative positions" means, if the polyfunctional (meth)acrylic compound (X1) has only two (meth)acryloyloxy groups, those two (meth)acryloyloxy groups, and if the polyfunctional (meth)acrylic compound (X1) has three or more (meth)acryloyloxy groups, the two (meth)acryloyloxy groups in the furthest relative positions among them.

[0016] The above-mentioned polyfunctional (meth)acrylic compound (X1) has two or more (meth)acryloyloxy groups. In particular, it is preferable that the above-mentioned polyfunctional (meth)acrylic compound (X1) has only two (meth)acryloyloxy groups.

[0017] The polyfunctional (meth)acrylic compound (X1) described above has a minimum distance of 1 to 6 atoms between (meth)acryloyloxy groups. This range of minimum distance between (meth)acryloyloxy groups in the polyfunctional (meth)acrylic compound (X1) results in the liquid crystal display element sealant of this embodiment 1 exhibiting excellent high-temperature adhesion, moisture permeability prevention, and low liquid crystal contamination. Preferably, the minimum distance between (meth)acryloyloxy groups in the polyfunctional (meth)acrylic compound (X1) is 1 to 3. Furthermore, a preferred lower limit for the minimum distance between (meth)acryloyloxy groups in the polyfunctional (meth)acrylic compound (X1) is 2. Note that the "number of atoms in the shortest distance between (meth)acryloyloxy groups" mentioned above does not include the number of atoms contained in the (meth)acryloyloxy group itself. For example, in the case of the compound represented by formula (1) above, one (meth)acryloyloxy group is connected to the other (meth)acryloyloxy group by four covalent bonds, and between the two (meth)acryloyloxy groups, the atoms constituting these four covalent bonds are three carbon atoms. Therefore, the number of atoms in the shortest distance between (meth)acryloyloxy groups is 3, resulting in the polyfunctional (meth)acrylic compound (X1). Furthermore, for example, in the case of tricyclodecanedimethanol diacrylate represented by formula (3) below, one acryloyloxy group is connected to the other acryloyloxy group by a minimum of eight covalent bonds, and between the two acryloyloxy groups, the atoms constituting these eight covalent bonds are seven carbon atoms. Therefore, the minimum distance of atoms between (meth)acryloyloxy groups is seven, and it does not become the polyfunctional (meth)acrylic compound (X1). Moreover, for example, in the case of dipentaerythritol hexaacrylate represented by formula (4) below, the two acryloyloxy groups that are furthest apart are connected to the other acryloyloxy group by a minimum of eight covalent bonds, and between the two acryloyloxy groups, the atoms constituting these eight covalent bonds are six carbon atoms and one oxygen atom. Therefore, the minimum distance of atoms between (meth)acryloyloxy groups is seven, and it does not become the polyfunctional (meth)acrylic compound (X1). In this specification, "(meth)acrylate" means acrylate or methacrylate.

[0018] [ka]

[0019] [ka]

[0020] The above-mentioned polyfunctional (meth)acrylic compound (X1) has a preferred upper limit of 130 in terms of (meth)acryloyloxy group equivalents. When the (meth)acryloyloxy group equivalent of the above-mentioned polyfunctional (meth)acrylic compound (X1) is 130 or less, the resulting sealant for liquid crystal display elements has superior high-temperature adhesion, moisture permeability prevention, and low liquid crystal contamination. A more preferred upper limit of 120 in terms of (meth)acryloyloxy group equivalents of the above-mentioned polyfunctional (meth)acrylic compound (X1) is 120. Furthermore, there is no particular preferred lower limit for the (meth)acryloyloxy group equivalent of the above-mentioned polyfunctional (meth)acrylic compound (X1), but the practical lower limit is 92. In this specification, the above-mentioned "(meth)acryloyloxy group equivalent" means the value obtained by dividing the molecular weight of a compound having a (meth)acryloyloxy group by the number of (meth)acryloyloxy groups in one molecule of the compound having a (meth)acryloyloxy group.

[0021] The polyfunctional (meth)acrylic compound (X1) described above preferably has at least one hydroxyl group in one molecule. The presence of the hydroxyl group in the polyfunctional (meth)acrylic compound (X1) results in a sealant for liquid crystal display elements that exhibits superior low liquid crystal contamination properties. Furthermore, if the polyfunctional (meth)acrylic compound (X1) has the hydroxyl groups, from the viewpoint of preventing moisture permeability, it is preferable that the number of hydroxyl groups in one molecule of the polyfunctional (meth)acrylic compound (X1) is 4 or less.

[0022] Examples of the above-mentioned polyfunctional (meth)acrylic compound (X1) include, for example, the compound represented by formula (1) above, ethylene glycol di(meth)acrylate, 1,3-propanediol di(meth)acrylate, 1,3-butanediol di(meth)acrylate, 1,4-butanediol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, 1,4-cyclohexanedimethanol diacrylate, diethylene glycol di(meth)acrylate, 2-n-butyl-2-ethyl-1,3-propanediol di(meth)acrylate, neopentyl glycol di(meth)acrylate, trimethylolpropane tri(meth)acrylate, glycerol tri(meth)acrylate, pentaerythritol tri(meth)acrylate, and the like. In particular, the resulting sealant for liquid crystal display elements is superior in high-temperature adhesion, moisture permeability prevention, and low liquid crystal contamination, so the polyfunctional (meth)acrylic compound (X1) is preferably the compound represented by formula (1) above.

[0023] The preferred lower limit for the content of the polyfunctional (meth)acrylic compound (X1) in 100 parts by mass of the above curable resin is 5 parts by mass, and the preferred upper limit is 42 parts by mass. When the content of the polyfunctional (meth)acrylic compound (X1) is within this range, the resulting sealant for liquid crystal display elements exhibits superior high-temperature adhesion and moisture permeability prevention. A more preferred lower limit for the content of the polyfunctional (meth)acrylic compound (X1) is 8 parts by mass, and a more preferred upper limit is 25 parts by mass.

[0024] In the sealant for liquid crystal display elements of this second embodiment, the (meth)acrylic compound comprises a polyfunctional (meth)acrylic compound (X2) having two or more (meth)acryloyloxy groups in one molecule and having a (meth)acryloyloxy group equivalent of 130 or less. By containing the polyfunctional (meth)acrylic compound (X2), the sealant for liquid crystal display elements of this second embodiment exhibits excellent high-temperature adhesion, moisture permeability prevention, and low liquid crystal contamination.

[0025] The above-mentioned polyfunctional (meth)acrylic compound (X2) has two or more (meth)acryloyloxy groups. In particular, it is preferable that the above-mentioned polyfunctional (meth)acrylic compound (X2) has only two (meth)acryloyloxy groups.

[0026] The above-mentioned polyfunctional (meth)acrylic compound (X2) has an upper limit of 130 (meth)acryloyloxy group equivalents. By having a (meth)acryloyloxy group equivalent of 130 or less in the above-mentioned polyfunctional (meth)acrylic compound (X2), the resulting sealant for liquid crystal display elements will have excellent high-temperature adhesion, moisture permeability prevention, and low liquid crystal contamination properties. The preferred upper limit of the (meth)acryloyloxy group equivalent of the above-mentioned polyfunctional (meth)acrylic compound (X2) is 120. Furthermore, there is no particular preferred lower limit for the (meth)acryloyloxy group equivalent of the above-mentioned polyfunctional (meth)acrylic compound (X2), but the practical lower limit is 92.

[0027] The polyfunctional (meth)acrylic compound (X2) described above preferably has a minimum distance of 1 to 6 atoms between (meth)acryloyloxy groups. Having the minimum distance of 1 atoms between (meth)acryloyloxy groups in the polyfunctional (meth)acrylic compound (X2) within this range results in the liquid crystal display element sealant of this second embodiment exhibiting superior high-temperature adhesion, moisture permeability prevention, and low liquid crystal contamination. More preferably, the minimum distance of 1 to 3 atoms between (meth)acryloyloxy groups in the polyfunctional (meth)acrylic compound (X2) is 2.

[0028] The above-mentioned polyfunctional (meth)acrylic compound (X2) preferably has at least one hydroxyl group in one molecule. The presence of the above-mentioned hydroxyl group in the polyfunctional (meth)acrylic compound (X2) results in a sealant for liquid crystal display elements that exhibits superior low liquid crystal contamination properties. Furthermore, if the polyfunctional (meth)acrylic compound (X2) has the hydroxyl groups, from the viewpoint of preventing moisture permeability, it is preferable that the number of hydroxyl groups in one molecule of the polyfunctional (meth)acrylic compound (X2) is 4 or less.

[0029] Examples of the above-mentioned polyfunctional (meth)acrylic compound (X2) include, for example, the compound represented by formula (2) above, ethylene glycol di(meth)acrylate, 1,3-propanediol di(meth)acrylate, 1,3-butanediol di(meth)acrylate, 1,4-butanediol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, 1,4-cyclohexanedimethanol diacrylate, diethylene glycol di(meth)acrylate, 2-n-butyl-2-ethyl-1,3-propanediol di(meth)acrylate, neopentyl glycol di(meth)acrylate, trimethylolpropane tri(meth)acrylate, glycerol tri(meth)acrylate, pentaerythritol tri(meth)acrylate, dipentaerythritol penta(meth)acrylate, dipentaerythritol hexa(meth)acrylate, and the like. In particular, the resulting sealant for liquid crystal display elements is superior in high-temperature adhesion, moisture permeability prevention, and low liquid crystal contamination, so the polyfunctional (meth)acrylic compound (X2) is preferably a compound represented by formula (2) above.

[0030] The preferred lower limit for the content of the polyfunctional (meth)acrylic compound (X2) in 100 parts by mass of the curable resin is 5 parts by mass, and the preferred upper limit is 42 parts by mass. When the content of the polyfunctional (meth)acrylic compound (X2) is within this range, the resulting sealant for liquid crystal display elements exhibits superior high-temperature adhesion and moisture permeability prevention. A more preferred lower limit for the content of the polyfunctional (meth)acrylic compound (X2) is 8 parts by mass, and a more preferred upper limit is 25 parts by mass.

[0031] In the sealant for liquid crystal display elements of this embodiment, the curable resin may contain other (meth)acrylic compounds other than the polyfunctional (meth)acrylic compound (X1) and the polyfunctional (meth)acrylic compound (X2).

[0032] As the above-mentioned other (meth)acrylic compounds, monofunctional (meth)acrylic compounds and other polyfunctional (meth)acrylic compounds other than the above-mentioned polyfunctional (meth)acrylic compound (X1) and polyfunctional (meth)acrylic compound (X2) can be used.

[0033] Examples of the above monofunctional (meth)acrylic compounds include methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, t-butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, n-octyl (meth)acrylate, isooctyl (meth)acrylate, isononyl (meth)acrylate, isodecyl (meth)acrylate, lauryl (meth)acrylate, and isomiris. Tyl (meth)acrylate, stearyl (meth)acrylate, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, cyclohexyl (meth)acrylate, isobornyl (meth)acrylate, bicyclopentenyl (meth)acrylate, benzyl (meth)acrylate, 2-methoxyethyl (meth)acrylate, 2-ethoxyethyl (meth)acrylate 2-Butoxyethyl (meth)acrylate, 2-Phenoxyethyl (meth)acrylate, Methoxyethylene glycol (meth)acrylate, Methoxypolyethylene glycol (meth)acrylate, Phenoxydiethylene glycol (meth)acrylate, Phenoxypolyethylene glycol (meth)acrylate, Tetrahydrofurfuryl (meth)acrylate, Ethyl carbitol (meth)acrylate, 2,2,2-Trifluoroethyl (meth)acrylate, 2,2,3,3-T Examples include trafluoropropyl (meth)acrylate, 1H,1H,5H-octafluoropentyl (meth)acrylate, imide (meth)acrylate, dimethylaminoethyl (meth)acrylate, diethylaminoethyl (meth)acrylate, 2-(meth)acryloyloxyethyl succinic acid, 2-(meth)acryloyloxyethyl hexahydrophthalic acid, 2-(meth)acryloyloxyethyl 2-hydroxypropyl phthalate, and 2-(meth)acryloyloxyethyl phosphate.

[0034] Examples of the above-mentioned other polyfunctional (meth)acrylic compounds include epoxy (meth)acrylate, (meth)acrylic acid ester compounds, urethane (meth)acrylate, and compounds other than the above-mentioned polyfunctional (meth)acrylic compound (X1) and polyfunctional (meth)acrylic compound (X2). In particular, it is preferable that the above-mentioned curable resin contains the above-mentioned epoxy (meth)acrylate as one of the above-mentioned other polyfunctional (meth)acrylic compounds. In this specification, "epoxy (meth)acrylate" refers to a compound obtained by reacting all epoxy groups in an epoxy compound with (meth)acrylic acid.

[0035] Examples of the epoxy (meth)acrylate mentioned above include those obtained by reacting an epoxy compound having two or more epoxy groups in one molecule with (meth)acrylic acid in the presence of a basic catalyst according to a conventional method.

[0036] Examples of epoxy compounds that serve as raw materials for the epoxy (meth)acrylates mentioned above include bisphenol A type epoxy compounds, bisphenol F type epoxy compounds, bisphenol E type epoxy compounds, bisphenol S type epoxy compounds, 2,2'-diallylbisphenol A type epoxy compounds, hydrogenated bisphenol type epoxy compounds, propylene oxide-added bisphenol A type epoxy compounds, caprolactone-modified bisphenol A type epoxy compounds, resorcinol type epoxy compounds, biphenyl type epoxy compounds, sulfide type epoxy compounds, diphenyl ether type epoxy compounds, dicyclopentadiene type epoxy compounds, naphthalene type epoxy compounds, phenol novolac type epoxy compounds, orthocresol novolac type epoxy compounds, dicyclopentadiene novolac type epoxy compounds, biphenyl novolac type epoxy compounds, naphthalene phenol novolac type epoxy compounds, glycidylamine type epoxy compounds, alkyl polyol type epoxy compounds, rubber-modified epoxy compounds, glycidyl ester compounds, and the like.

[0037] Examples of bifunctional (meth)acrylic acid ester compounds among the above include 1,9-nonanediol di(meth)acrylate, 1,10-decanediol di(meth)acrylate, triethylene glycol di(meth)acrylate, tetraethylene glycol di(meth)acrylate, polyethylene glycol di(meth)acrylate, dipropylene glycol di(meth)acrylate, tripropylene glycol di(meth)acrylate, polypropylene glycol di(meth)acrylate, bisphenol A di(meth)acrylate, ethylene oxide-modified bisphenol A di(meth)acrylate, propylene oxide-modified bisphenol A di(meth)acrylate, bisphenol F di(meth)acrylate, ethylene oxide-modified bisphenol F di(meth)acrylate, propylene oxide-modified bisphenol F di(meth)acrylate, tricyclodecanedimethanol di(meth)acrylate, and ethylene oxide-modified isocyanuric acid di(meth)acrylate.

[0038] Examples of the above-mentioned (meth)acrylic acid ester compounds that have three or more functionalities include ethylene oxide-added isocyanuric acid tri(meth)acrylate, ethylene oxide-added trimethylolpropane tri(meth)acrylate, propylene oxide-added trimethylolpropane tri(meth)acrylate, caprolactone-modified trimethylolpropane tri(meth)acrylate, propylene oxide-added glycerol tri(meth)acrylate, and tris(meth)acryloyloxyethyl phosphate.

[0039] The above-mentioned urethane (meth)acrylate can be obtained, for example, by reacting an isocyanate compound with a (meth)acrylic acid derivative having a hydroxyl group in the presence of a catalytic amount of a tin-based compound.

[0040] Examples of isocyanate compounds that serve as raw materials for the above-mentioned urethane (meth)acrylate include isophorone diisocyanate, 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, hexamethylene diisocyanate, trimethylhexamethylene diisocyanate, diphenylmethane-4,4'-diisocyanate (MDI), hydrogenated MDI, polymeric MDI, 1,5-naphthalene diisocyanate, norbornane diisocyanate, tollidine diisocyanate, xylylene diisocyanate (XDI), hydrogenated XDI, lysine diisocyanate, triphenylmethane triisocyanate, tris(isocyanatephenyl)thiophosphate, tetramethylxylylene diisocyanate, and 1,6,11-undecane triisocyanate.

[0041] Furthermore, as the isocyanate compound used as a raw material for the above-mentioned urethane (meth)acrylate, a chain-extended isocyanate compound obtained by the reaction of a polyol with an excess isocyanate compound can also be used. Examples of the polyols mentioned above include ethylene glycol, propylene glycol, glycerin, sorbitol, trimethylolpropane, carbonate diol, polyether diol, polyester diol, and polycaprolactone diol.

[0042] Examples of (meth)acrylic acid derivatives having the hydroxyl group mentioned above include hydroxyalkyl (meth)acrylates, mono(meth)acrylates of dihydric alcohols, mono(meth)acrylates or di(meth)acrylates of trihydric alcohols, epoxy (meth)acrylates, and the like. Examples of the hydroxyalkyl (meth)acrylates mentioned above include 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, and 4-hydroxybutyl (meth)acrylate. Examples of the dihydric alcohols mentioned above include ethylene glycol, propylene glycol, 1,3-propanediol, 1,3-butanediol, 1,4-butanediol, polyethylene glycol, and the like. Examples of the above-mentioned trivalent alcohols include trimethylolethane, trimethylolpropane, and glycerin. Examples of the epoxy (meth)acrylates mentioned above include bisphenol A type epoxy (meth)acrylate.

[0043] In the sealant for liquid crystal display elements of this embodiment, the preferred lower limit of the total content of the (meth)acrylic compound in 100 parts by mass of the curable resin is 50 parts by mass, and the preferred upper limit is 99 parts by mass. Having the total content of the (meth)acrylic compound within this range results in a sealant for liquid crystal display elements that exhibits superior curability, adhesion, and low liquid crystal contamination. A more preferred lower limit of the total content of the (meth)acrylic compound is 55 parts by mass, and a more preferred upper limit is 95 parts by mass.

[0044] In the sealant for liquid crystal display elements of this embodiment, the curable resin includes an epoxy compound. Examples of epoxy compounds included in the above-mentioned curable resin include bisphenol A type epoxy compounds, bisphenol F type epoxy compounds, bisphenol E type epoxy compounds, bisphenol S type epoxy compounds, 2,2'-diallylbisphenol A type epoxy compounds, hydrogenated bisphenol type epoxy compounds, propylene oxide-added bisphenol A type epoxy compounds, caprolactone-modified bisphenol A type epoxy compounds, resorcinol type epoxy compounds, biphenyl type epoxy compounds, sulfide type epoxy compounds, diphenyl ether type epoxy compounds, dicyclopentadiene type epoxy compounds, naphthalene type epoxy compounds, phenol novolac type epoxy compounds, orthocresol novolac type epoxy compounds, dicyclopentadiene novolac type epoxy compounds, biphenyl novolac type epoxy compounds, naphthalene phenol novolac type epoxy compounds, glycidylamine type epoxy compounds, alkyl polyol type epoxy compounds, rubber-modified epoxy compounds, glycidyl ester compounds, and the like.

[0045] Partially (meth)acrylic-modified epoxy compounds are also preferably used as the epoxy compounds mentioned above. In this specification, the term "partially (meth)acrylic modified epoxy compound" refers to a compound obtained by reacting a portion of the epoxy groups of an epoxy compound having two or more epoxy groups with (meth)acrylic acid, and having one or more epoxy groups and one or more (meth)acryloyl groups in one molecule. Although the above-mentioned partially (meth)acrylic modified epoxy compound has (meth)acryloyl groups, it is treated as the above-mentioned epoxy compound and not the above-mentioned (meth)acrylic compound.

[0046] Examples of commercially available particulate (meth)acrylic-modified epoxy compounds include UVACURE1561 and EBECRYL3605 (both manufactured by Daicel Ornex).

[0047] The preferred lower limit for the content of the epoxy compound in 100 parts by mass of the curable resin is 1 part by mass, and the preferred upper limit is 50 parts by mass. When the content of the epoxy compound is within this range, the resulting sealant for liquid crystal display elements exhibits superior curability, adhesion, and low liquid crystal contamination. A more preferred lower limit for the content of the epoxy compound is 5 parts by mass, and a more preferred upper limit is 45 parts by mass.

[0048] The preferred lower limit for the total content of the curable resin in 100 parts by mass of the sealant for liquid crystal display elements in this embodiment is 30 parts by mass, and the preferred upper limit is 90 parts by mass. Having the total content of the curable resin within this range results in a sealant for liquid crystal display elements with superior curability and adhesion.

[0049] The sealant for liquid crystal display elements in this embodiment contains a photoradical polymerization initiator. Examples of the above-mentioned photoradical polymerization initiators include benzophenone compounds, acetophenone compounds, acylphosphine oxide compounds, titanocene compounds, oxime ester compounds, benzoin ether compounds, and thioxanthone compounds. Examples of the above-mentioned photoradical polymerization initiators include, specifically, 1-hydroxycyclohexylphenyl ketone, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-1-butanone, 2-(dimethylamino)-2-((4-methylphenyl)methyl)-1-(4-(4-morpholinyl)phenyl)-1-butanone, 2,2-dimethoxy-1,2-diphenylethane-1-one, bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide, and 2-methyl-1-(4-methylthiophenyl). Examples include -2-morpholinopropan-1-one, 1-(4-(2-hydroxyethoxy)-phenyl)-2-hydroxy-2-methyl-1-propan-1-one, 1-(4-(phenylthio)phenyl)-1,2-octanedione 2-(O-benzoyloxime), 2-(acetoxyimino)-1-(4-(4-(2-hydroxyethoxy)phenylthio)phenyl)propan-1-one, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, and 2,4-dimethylthioxanthene-9-one.

[0050] The preferred lower limit for the content of the above-mentioned photoradical polymerization initiator is 0.1 parts by mass and the preferred upper limit is 10 parts by mass per 100 parts by mass of the above-mentioned curable resin. Having the content of the above-mentioned photoradical polymerization initiator within this range results in a sealant for liquid crystal display elements having superior storage stability and photocurability. A more preferred lower limit for the content of the above-mentioned photoradical polymerization initiator is 0.3 parts by mass and a more preferred upper limit is 5 parts by mass.

[0051] The sealant for liquid crystal display elements in this embodiment may contain a thermal radical polymerization initiator. Examples of the above-mentioned thermal radical polymerization initiators include those composed of azo compounds and organic peroxides. Among these, initiators composed of azo compounds (hereinafter also referred to as "azo initiators") are preferred from the viewpoint of suppressing liquid crystal contamination.

[0052] Examples of the above-mentioned azo compounds include those having a structure in which multiple units such as polyalkylene oxides and polydimethylsiloxanes are bonded via an azo group. As a polymer azo compound having a structure in which multiple units such as polyalkylene oxide are bonded via the above-mentioned azo group, one having a polyethylene oxide structure is preferred. Examples of the above-mentioned azo compounds include polycondensates of 4,4'-azobis(4-cyanopentanoic acid) and polyalkylene glycols, and polycondensates of 4,4'-azobis(4-cyanopentanoic acid) and polydimethylsiloxane having terminal amino groups. Examples of the above-mentioned azo initiators include VPE-0201, VPE-0401, VPE-0601, VPS-0501, VPS-1001, V-65, and V-501 (all manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.).

[0053] Examples of the above-mentioned organic peroxides include ketone peroxides, peroxyketals, hydroperoxides, dialkyl peroxides, peroxyesters, diacyl peroxides, and peroxydicarbonates.

[0054] The preferred lower limit for the content of the above-mentioned thermal radical polymerization initiator is 0.1 parts by mass and the preferred upper limit is 10 parts by mass per 100 parts by mass of the above-mentioned curable resin. Having the content of the above-mentioned thermal radical polymerization initiator within this range results in a sealant for liquid crystal display elements that exhibits superior storage stability and thermosetting properties. A more preferred lower limit for the content of the above-mentioned thermal radical polymerization initiator is 0.3 parts by mass and a more preferred upper limit is 5 parts by mass.

[0055] The sealant for liquid crystal display elements in this embodiment contains a thermosetting agent. Examples of the above-mentioned thermosetting agents include organic acid hydrazides, imidazole derivatives, amine compounds, polyhydric phenolic compounds, and acid anhydrides. Among these, organic acid hydrazides are preferably used.

[0056] Examples of the above-mentioned organic acid hydrazides include sebacate dihydrazide, isophthalic acid dihydrazide, adipic acid dihydrazide, and malonic acid dihydrazide. Examples of commercially available organic acid hydrazides include those manufactured by Otsuka Chemical Co., Ltd., Ajinomoto Fine Techno Co., Ltd., and Mitsubishi Gas Chemical Next Co., Ltd. Examples of organic acid hydrazides manufactured by Otsuka Chemical Co., Ltd. include SDH and ADH. Examples of organic acid hydrazides manufactured by Ajinomoto Fine Techno include Amicure VDH, Amicure VDH-J, Amicure UDH, and Amicure UDH-J. Examples of organic acid hydrazides manufactured by Mitsubishi Gas Chemical Next include MDH.

[0057] The preferred lower limit for the content of the above-mentioned thermosetting agent is 1 part by mass and the preferred upper limit is 50 parts by mass per 100 parts by mass of the above-mentioned curable resin. When the content of the above-mentioned thermosetting agent is within this range, the resulting sealant for liquid crystal display elements maintains storage stability and applicability while exhibiting superior thermosetting properties. A more preferred upper limit for the content of the above-mentioned thermosetting agent is 30 parts by mass.

[0058] The sealant for liquid crystal display elements of this embodiment preferably contains a filler for the purpose of improving viscosity, further improving adhesion through stress dispersion effect, improving coefficient of thermal expansion, and further improving moisture permeability.

[0059] Inorganic fillers and organic fillers can be used as the above-mentioned fillers. Examples of the inorganic fillers mentioned above include silica, talc, glass beads, asbestos, gypsum, diatomaceous earth, smectite, bentonite, montmorillonite, sericite, activated clay, alumina, zinc oxide, iron oxide, magnesium oxide, tin oxide, titanium oxide, calcium carbonate, magnesium carbonate, magnesium hydroxide, aluminum hydroxide, aluminum nitride, silicon nitride, barium sulfate, calcium silicate, and the like. Examples of the above-mentioned organic fillers include polyester microparticles, polyurethane microparticles, vinyl polymer microparticles, (meth)acrylic polymer microparticles, and the like. Furthermore, the above-mentioned organic fillers may have a core-shell structure.

[0060] The preferred lower limit for the content of the filler per 100 parts by mass of the curable resin is 10 parts by mass, and the preferred upper limit is 70 parts by mass. Having the filler content within this range allows for superior effects such as improved adhesion without degrading coatability. A more preferred lower limit for the filler content is 20 parts by mass, and a more preferred upper limit is 60 parts by mass.

[0061] The sealant for liquid crystal display elements of this embodiment preferably further contains a silane coupling agent. The silane coupling agent mainly serves as an adhesive aid for good adhesion between the sealant for liquid crystal display elements and the substrate, etc. Suitable silane coupling agents include, for example, 3-aminopropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, and 3-glycidoxypropyltrimethoxysilane.

[0062] The preferred lower limit for the content of the silane coupling agent per 100 parts by mass of the curable resin is 0.1 parts by mass, and the preferred upper limit is 10 parts by mass. Having the silane coupling agent content within this range provides superior effectiveness in suppressing liquid crystal contamination while improving adhesion. A more preferred lower limit for the silane coupling agent content is 0.3 parts by mass, and a more preferred upper limit is 5 parts by mass.

[0063] The sealant for liquid crystal display elements of this embodiment may further contain, if necessary, additives such as light-shielding agents, stress-relieving agents, reactive diluents, thixotropes, spacers, curing accelerators, defoamers, leveling agents, and polymerization inhibitors.

[0064] A method for manufacturing the sealant for liquid crystal display elements of this embodiment includes, for example, a method of mixing a curable resin, a photoradical polymerization initiator, a thermosetting agent, and other components used as needed, such as a filler or a silane coupling agent, using a mixer. Examples of the above-mentioned mixing machines include homodispers, homomixers, multi-purpose mixers, planetary mixers, kneaders, and three-roll mixers.

[0065] The sealant for liquid crystal display elements of this embodiment has a preferred lower limit of 110°C and a preferred upper limit of 170°C for the glass transition temperature of the cured product. Having the glass transition temperature of the cured product within this range results in superior high-temperature adhesion and moisture permeability prevention for the sealant for liquid crystal display elements of this embodiment. A more preferred lower limit for the glass transition temperature of the cured product is 120°C, a more preferred upper limit is 155°C, and an even more preferred upper limit is 145°C. In this specification, the glass transition temperature of the cured product can be obtained as the temperature at which the loss tangent (tanδ) is maximized when dynamic viscoelasticity is measured for a cured product with a thickness of 300 μm using a dynamic viscoelasticity measuring device under the following conditions: tensile mode, specimen width 5 mm, grip width 25 mm, heating rate 10 °C / min, temperature range -80 °C to 200 °C, and frequency 10 Hz. For example, the DVA-200 (manufactured by IT Measurement & Control Co., Ltd.) can be used as the dynamic viscoelasticity measuring device. Furthermore, the cured material used to measure the glass transition temperature is, for example, a sealant for liquid crystal display elements, measured at a wavelength of 365 nm and an illuminance of 100 mW / cm². 2 This can be obtained by irradiating with light for 30 seconds, followed by heating at 120°C for 60 minutes. The wavelength of light irradiated onto the liquid crystal display element sealant to obtain the above cured product is appropriately selected according to the type of photoradical polymerization initiator.

[0066] Furthermore, by incorporating conductive fine particles into the sealant for liquid crystal display elements of this embodiment, a conductive material can be manufactured that allows for both upward and downward conductivity. As the conductive fine particles mentioned above, metal balls, resin fine particles with a conductive metal layer formed on their surface, etc., can be used. Among these, resin fine particles with a conductive metal layer formed on their surface are preferred because, due to the excellent elasticity of the resin fine particles, conductive connections can be made without damaging transparent substrates, etc.

[0067] The sealant for liquid crystal display elements of this embodiment is suitably used in the manufacture of liquid crystal display elements. The above-mentioned liquid crystal display element typically includes a cured product of the sealant for the liquid crystal display element of this embodiment. As the above-mentioned liquid crystal display element, a liquid crystal display element with a narrow bezel design is preferred. Specifically, it is preferable that the width of the frame portion surrounding the liquid crystal display is 2 mm or less.

[0068] As a method for manufacturing the above-mentioned liquid crystal display element, the liquid crystal drop method is preferably used, and specifically, for example, a method having the following steps can be cited. First, a frame-shaped sealing pattern is formed by applying the liquid crystal display element sealant of this embodiment to one of two transparent substrates having electrodes and alignment films such as ITO thin films using screen printing, dispenser coating, etc. Next, minute droplets of liquid crystal are dropped onto the entire surface within the frame of the sealing pattern, and the other transparent substrate is placed on top of it under vacuum. After that, a liquid crystal display element can be obtained by irradiating the sealing pattern portion with light such as ultraviolet light to partially cure the sealant (photocuring step), and then heating the partially cured sealant to fully cure it (thermocuring step). When manufacturing the above-mentioned liquid crystal display element, it is preferable that the application width of the sealant for the liquid crystal display element in this embodiment is 1 mm or less.

[0069] Furthermore, the use of a curable resin composition containing a curable resin, a photoradical polymerization initiator, and a thermosetting agent, wherein the curable resin includes a (meth)acrylic compound without epoxy groups and an epoxy compound, the (meth)acrylic compound having two or more (meth)acryloyloxy groups in one molecule, and the number of atoms constituting the shortest covalent bond connecting one (meth)acryloyloxy group to the other (meth)acryloyloxy group between the two (meth)acryloyloxy groups furthest apart, is between 1 and 6, as a sealant for liquid crystal display elements is also one embodiment of the present invention. In the curable resin composition in this embodiment, the components and physical properties are the same as those of the sealant for liquid crystal display elements in Embodiment 1.

[0070] Furthermore, the use of a curable resin composition containing a curable resin, a photoradical polymerization initiator, and a thermosetting agent, wherein the curable resin contains a (meth)acrylic compound without epoxy groups and an epoxy compound, and the (meth)acrylic compound contains two or more (meth)acryloyloxy groups in one molecule and a polyfunctional (meth)acrylic compound (X2) with a (meth)acryloyloxy group equivalent of 130 or less, as a sealant for liquid crystal display elements is also one embodiment of the present invention. In the curable resin composition in this embodiment, the components and physical properties are the same as those of the sealant for liquid crystal display elements in this second embodiment. [Effects of the Invention]

[0071] According to the present invention, it is possible to provide a sealant for liquid crystal display elements that is excellent in high-temperature adhesion, moisture permeability prevention, and low liquid crystal contamination. Furthermore, according to the present invention, it is possible to provide a method for using a curable resin composition as a sealant for liquid crystal display elements. [Modes for carrying out the invention]

[0072] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples.

[0073] (Example 1~ 8. Reference Example 9. Comparative Examples 1-4) According to the mixing ratios listed in Tables 1 and 2, each material was stirred using a planetary agitator, and then uniformly mixed using a ceramic three-roller system to produce the results of Example 1~ 8. Reference Example 9. Comparative Examples 1 to 4 sealants for liquid crystal display elements were obtained. A planetary agitator, Awatori Rentaro (manufactured by Shinky Co., Ltd.), was used.

[0074] Examples Reference example and 、 The materials used in the comparative example are as follows: <Curing resin> ((meth)acrylic compounds) • 2-Hydroxy-1,3-Dimethacryloxypropane:NK Ester 701 (manufactured by Shin-Nakamura Chemical Industry Co., Ltd.), shortest distance between methacryloyloxy groups: 3, equivalent weight of methacryloyloxy groups: 114, contains hydroxyl groups • Neopentyl glycol dimethacrylate:NK ester NPG (manufactured by Shin-Nakamura Chemical Industry Co., Ltd.), shortest distance between methacryloyloxy groups: 3, methacryloyloxy group equivalent: 120, no hydroxyl groups. • 1,6-Hexanediol dimethacrylate: Manufactured by Tokyo Chemical Industry Co., Ltd., shortest distance between methacryloyloxy groups: 6, equivalent weight of methacryloyloxy groups: 127, no hydroxyl groups. Trimethylolpropane triacrylate: Manufactured by Tokyo Chemical Industry Co., Ltd., shortest distance between acryloyloxy groups: 3 atoms, acryloyloxy group equivalent: 99, no hydroxyl groups. Tricyclodecanedimethanol diacrylate: IRR214K (manufactured by Daicel Ornex), shortest distance between acryloyloxy groups: 7 atoms, acryloyloxy group equivalent: 152, no hydroxyl groups. • Resorcinol-type epoxy acrylate: RGDA (manufactured by Kyoeisha Chemical Co., Ltd.), shortest distance between acryloyloxy groups: 11 atoms, acryloyloxy group equivalent: 183, contains hydroxyl groups. • Caprolactone-modified bisphenol A type epoxy acrylate: EBECRYL3708 (manufactured by Daicel Ornex), shortest distance between acryloyloxy groups: 61, acryloyloxy group equivalent: 663, hydroxyl group present. • Ethylene oxide-added isocyanuric acid (di / tri)acrylate: Aronics M-315 (manufactured by Toagosei Co., Ltd.), 7 atoms in the shortest distance between acryloyloxy groups, acryloyloxy group equivalent weight 141 or 185, some hydroxyl groups present. • Bisphenol A type epoxy acrylate: EBECRYL3700 (manufactured by Daicel Ornex), shortest distance between acryloyloxy groups: 17, acryloyloxy group equivalent: 242, contains hydroxyl groups. • Bisphenol A type epoxy methacrylate: Epoxy ester 3000MK (manufactured by Kyoeisha Chemical Co., Ltd.), shortest distance between methacryloyloxy groups: 17 atoms, equivalent weight of methacryloyloxy groups: 256, contains hydroxyl groups. (Epoxy compound) • Partially acrylic-modified bisphenol A epoxy compound: UVACURE1561 (manufactured by Daicel Ornex Co., Ltd.) <Photoradical polymerization initiator> 2-(acetoxyimino)-1-(4-(4-(2-hydroxyethoxy)phenylthio)phenyl)propan-1-one: ADEKA Arcules NCI-930 (manufactured by ADEKA) <Thermosetting agent> • Dihydrazide malonate: MDH (manufactured by Mitsubishi Gas Chemical Next Co., Ltd.) <Filler> • Silica: Sunseal SP-07M (manufactured by Tokuyama Corporation) <Silane coupling agent> • 3-Glycidoxypropyltrimethoxysilane: Sylace S510 (manufactured by Chisso Corporation)

[0075] (Glass transition temperature of the cured material) The obtained sealant for liquid crystal display elements was tested using a metal halide lamp at a wavelength of 365 nm and an illuminance of 100 mW / cm². 2 After irradiating with light for 30 seconds, a cured material with a thickness of 300 μm was obtained by heating at 120°C for 60 minutes. The obtained cured material was subjected to dynamic viscoelasticity measurement using a dynamic viscoelasticity measuring device (DVA-200, manufactured by IT Measurement Control Co., Ltd.) under the following conditions: tensile mode, specimen width 5 mm, grip width 25 mm, heating rate 10 °C / min, temperature range -80 °C to 200 °C, and frequency 10 Hz. The glass transition temperature was then determined. The results are shown in Tables 1 and 2.

[0076] <Rating> Examples Reference example and 、 The following evaluations were performed on the liquid crystal display element sealants obtained in the comparative examples. The results are shown in Tables 1 and 2.

[0077] (High temperature adhesive) A substrate with an alignment film was fabricated by spin-coating a polyimide resin onto a glass substrate with an ITO thin film, pre-baking it at 80°C, and then firing it at 230°C. SE7492 (manufactured by Nissan Chemical Corporation) was used as the polyimide resin. Two alignment-film-coated substrates were prepared in this manner. The liquid crystal display element sealant obtained was dotted onto one of the alignment-film-coated substrates so that the diameter of the dotted sealant would be 3 mm when the substrates were bonded together. The alignment-film-coated substrate with the sealant dotted onto it and the other alignment-film-coated substrate were then bonded together in a cross shape using the sealant. Afterward, a metal halide lamp was used at a wavelength of 365 nm and an illuminance of 100 mW / cm². 2 After irradiating with light for 30 seconds, the specimens were heated at 120°C for 60 minutes to obtain adhesive test pieces. A total of 12 adhesive test pieces were prepared in the same manner. The obtained adhesive test pieces were left to stand for 24 hours in an environment of 121°C, 100% RH, and 2 atm, and the presence or absence of peeling of the cured sealant was checked visually. High-temperature adhesion was evaluated according to the following criteria. ○: If 75% (9 or more) of the adhesive test pieces did not peel off. △: No peeling was observed in 25% (3 pieces) to less than 75% (9 pieces) of the adhesive test specimens. ×: If less than 25% (3 pieces) of the adhesive test specimens did not peel off.

[0078] (Moisture-proof properties) The obtained liquid crystal display element sealant was applied to a smooth release film using a coater to a thickness of 200-300 μm. Then, a metal halide lamp was used at a wavelength of 365 nm and an illuminance of 100 mW / cm². 2 After irradiating the liquid crystal display element sealant with light for 30 seconds, it was heated at 120°C for 60 minutes to cure it, and a film for measuring moisture permeability was obtained. A cup for measuring moisture permeability was prepared in accordance with the method for testing moisture permeability of moisture-proof packaging materials (cup method) of JIS Z 0208:1976, the obtained film for measuring moisture permeability was attached to the cup, and the cup was placed in a constant temperature and humidity oven at 85°C and 85%RH to measure the moisture permeability, and the moisture permeability prevention performance was evaluated according to the following criteria. ◎: Moisture permeability of 50g / m 2 • If it was less than 24 hours ○: Moisture permeability of 50g / m 2 ·55g / m over 24hr 2 • If it was less than 24 hours ×: Moisture permeability is 55g / m 2 • If it was 24 hours or more

[0079] (Low liquid crystal contamination) 0.5g of positive-type liquid crystal (JNC Corporation, "JC-7129XX") was placed in a sample vial, 0.1g of the obtained liquid crystal display element sealant was added and shaken, then heated at 120°C for 60 minutes and returned to room temperature (25°C). The obtained liquid crystal display element sealant was applied to the alignment film (Nissan Chemical Corporation, "RB-089") of a glass substrate having a transparent electrode and an alignment-treated film, using a dispenser to draw a square frame. Subsequently, minute droplets of liquid crystal taken from the sample vial were dropped onto the entire area within the sealant frame on the substrate, and another glass substrate was placed on top in a vacuum. The vacuum was released, and a metal halide lamp was used at a wavelength of 365nm and an illuminance of 100mW / cm². 2 After irradiating with light for 30 seconds, the sealant was cured by heating at 120°C for 60 minutes to obtain a liquid crystal display element. For the obtained liquid crystal display elements, a liquid crystal property evaluation system (Toyo Technica Co., Ltd., "Model 6254") was used to apply an AC voltage of 10V, 0.1Hz at 25°C and measure the retained voltage after 1 second. The voltage retention rate of the liquid crystal was calculated, and the low liquid crystal contamination properties were evaluated according to the following criteria. ◎: When the voltage retention rate is 95% or higher ○: When the voltage retention rate is 90% or more but less than 95% △: When the voltage retention rate is 80% or more but less than 90% ×: If the voltage retention rate is less than 80%

[0080] [Table 1]

[0081] [Table 2] [Industrial applicability]

[0082] According to the present invention, it is possible to provide a sealant for liquid crystal display elements that is excellent in high-temperature adhesion, moisture permeability prevention, and low liquid crystal contamination. Furthermore, according to the present invention, it is possible to provide a method for using a curable resin composition as a sealant for liquid crystal display elements.

Claims

1. It contains a curable resin, a photoradical polymerization initiator, and a thermosetting agent. The curable resin comprises a (meth)acrylic compound that does not have an epoxy group, and an epoxy compound. The (meth)acrylic compound includes a polyfunctional (meth)acrylic compound (X1) having two (meth)acryloyloxy groups in one molecule, and the number of atoms constituting the shortest possible covalent bond between the two (meth)acryloyloxy groups is 1 to 6. The glass transition temperature of the cured product is between 110°C and 170°C. A sealant for liquid crystal display elements characterized by the following features.

2. The sealant for liquid crystal display elements according to claim 1, wherein the polyfunctional (meth)acrylic compound (X1) has 1 or more atoms that constitute the shortest possible covalent bond connecting one (meth)acryloyloxy group to the other (meth)acryloyloxy group in the two (meth)acryloyloxy groups.

3. The polyfunctional (meth)acrylic compound (X1) has at least one hydroxyl group in one molecule, as described in claim 1 or 2, as a sealant for liquid crystal display elements.

4. The sealant for liquid crystal display elements according to claim 3, wherein the polyfunctional (meth)acrylic compound (X1) is a compound represented by the following formula (1). 【Chemistry 1】 In formula (1), R １ and R ２ Each is independently a hydrogen atom or a methyl group, and R ３ ~R ８ Each of these is independently a hydrogen atom, an alkyl group having 1 to 3 carbon atoms, or a hydroxyl group, and R ３ ~R ８ At least one of them is a hydroxyl group.

5. The sealing agent for liquid crystal display elements according to claim 1 or 2, wherein the content of the polyfunctional (meth)acrylic compound (X1) in 100 parts by mass of the curable resin is 5 parts by mass or more and 42 parts by mass or less.

6. It contains a curable resin, a photoradical polymerization initiator, and a thermosetting agent. The curable resin comprises a (meth)acrylic compound that does not have an epoxy group, and an epoxy compound. The (meth)acrylic compound includes a polyfunctional (meth)acrylic compound (X2) having two (meth)acryloyloxy groups in one molecule and having an equivalent amount of (meth)acryloyloxy groups of 130 or less. The glass transition temperature of the cured product is between 110°C and 170°C. A sealant for liquid crystal display elements characterized by the following features.

7. The polyfunctional (meth)acrylic compound (X2) has at least one hydroxyl group in one molecule, as described in claim 6, as a sealant for liquid crystal display elements.

8. The sealant for liquid crystal display elements according to claim 7, wherein the polyfunctional (meth)acrylic compound (X2) is a compound represented by the following formula (2). 【Chemistry 2】 In formula (2), R ９ and R １０ are each independently a hydrogen atom or a methyl group, and R １１ to R １６ are each independently a hydrogen atom, an alkyl group having 1 to 3 carbon atoms, or a hydroxyl group, and R １１ to R １６ has at least one hydroxyl group.

9. The sealing agent for liquid crystal display elements according to any one of claims 6 to 8, wherein the content of the polyfunctional (meth)acrylic compound (X2) in 100 parts by mass of the curable resin is 5 parts by mass or more and 42 parts by mass or less.

10. It contains a curable resin, a photoradical polymerization initiator, and a thermosetting agent. The curable resin comprises a (meth)acrylic compound that does not have an epoxy group, and an epoxy compound. The (meth)acrylic compound includes a polyfunctional (meth)acrylic compound (X1) having two (meth)acryloyloxy groups in one molecule, and the number of atoms constituting the shortest possible covalent bond between the two (meth)acryloyloxy groups is 1 to 6. The glass transition temperature of the cured product is between 110°C and 170°C. Use of a curable resin composition characterized by the above as a sealant for liquid crystal display elements.

11. It contains a curable resin, a photoradical polymerization initiator, and a thermosetting agent. The curable resin comprises a (meth)acrylic compound that does not have an epoxy group, and an epoxy compound. The (meth)acrylic compound includes a polyfunctional (meth)acrylic compound (X2) having two (meth)acryloyloxy groups in one molecule and having an equivalent amount of (meth)acryloyloxy groups of 130 or less. The glass transition temperature of the cured product is between 110°C and 170°C. Use of a curable resin composition characterized by the above as a sealant for liquid crystal display elements.

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