Liquid crystal display element sealing agent, and use of curable resin composition for liquid crystal display element sealing agent

Abstract

A purpose of the present invention is to provide a liquid crystal display element sealing agent which has excellent storage stability in a heated state, adhesiveness to an alignment film, and low liquid-crystal-contaminating property. Another purpose of the present invention is to provide a method for using a curable resin composition for said liquid crystal display element sealing agent. The present invention pertains to a liquid crystal display element sealing agent which contains a curable resin and a thermosetting agent and in which: the curable resin includes at least one curable resin selected from the group consisting of compounds represented by formula (1-1) and compounds represented by formula (1-2); and the thermosetting agent includes a compound that has at least two of primary amino groups and / or hydrazide groups per molecule in total and has a sulfonyl group bonded to an aromatic ring. In formulae (1-1) and (1-2): R1 represents a hydrogen atom or a methyl group; R2 represents a group represented by formula (2-1), (2-2), or (2-3); R3 represents a structure derived from a dicarboxylic acid or an anhydride thereof; X represents a ring-opened structure of a lactone; n is 0-5; and Ep represents a structure derived from a bifunctional or higher functional epoxy compound. In formulae (2-1) to (2-3), * represents a bonding position. In formula (2-2), a is an integer of 1-5. In formula (2-3), b is an integer of 1-5, c is an integer of 1-5, and d is an integer of 1-5.

Description

Use of liquid crystal display element sealants and curable resin compositions as liquid crystal display element sealants.

[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.

[0002] As a method for manufacturing liquid crystal display elements such as liquid crystal display cells, a liquid crystal dropping method using a sealant, as disclosed in Patent Documents 1 and 2, is used, from the viewpoint of shortening the cycle time and optimizing the amount of liquid crystal used. In the dropping method, first, a frame-shaped seal pattern is formed on one of two electrode-equipped substrates by dispensing. Next, while the sealant is still uncured, minute droplets of liquid crystal are dropped into the frame of the seal pattern, and the other substrate is placed on top of it under vacuum. After the sealant is cured, a liquid crystal display element is manufactured. Currently, this dropping method is the mainstream method for manufacturing liquid crystal display elements.

[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 urgent 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).

[0004] Japanese Patent Publication No. 2001-133794, International Publication No. 02 / 092718

[0005] In narrow-bezel designs, the sealant is also placed on the alignment film, thus requiring a sealant for liquid crystal display elements that exhibits excellent adhesion not only to the substrate but also to the alignment film. Such sealants for liquid crystal display elements exhibit high adhesive strength through photocuring and thermal curing, and one method of imparting thermal curing is to incorporate a thermal curing agent into the sealant for liquid crystal display elements. However, when a thermal curing agent with a low reaction initiation temperature is used to improve the curability and adhesion of the sealant for liquid crystal display elements, the resulting sealant for liquid crystal display elements sometimes has poor storage stability. In particular, in order to accommodate narrow-bezel designs, the sealant is applied under heating conditions to make the application width narrower, but prolonged heating can cause the sealant to thicken. On the other hand, when a thermal curing agent with a high reaction initiation temperature is used, there is a risk of liquid crystal contamination due to the elution of uncured sealant components into the liquid crystal. Therefore, there has been a demand for a sealant with superior low liquid crystal contamination properties.

[0006] The present invention aims to provide a sealant for liquid crystal display elements that exhibits excellent storage stability under heated conditions, adhesion to alignment films, 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.

[0007] Disclosure 1 is a sealant for liquid crystal display elements containing a curable resin and a thermosetting agent, wherein the curable resin comprises at least one curable resin selected from the group consisting of a compound represented by the following formula (1-1) and a compound represented by the following formula (1-2), and the thermosetting agent comprises a compound having a total of two or more primary amino groups and hydrazide groups in one molecule, and a sulfonyl group bonded to an aromatic ring. Disclosure 2 is a sealant for liquid crystal display elements in which, in the following formulas (1-1) and (1-2), R ３This is a sealant for liquid crystal display elements according to Disclosure 1, having a structure represented by the following formulas (3-1), (3-2), (3-3), or (3-4). Disclosure 3 is a sealant for liquid crystal display elements according to Disclosure 1 or 2, wherein the content of at least one curable resin selected from the group consisting of the compound represented by formula (1-1) and the compound represented by formula (1-2) in 100 parts by mass of the curable resin is 5 parts by mass or more and 40 parts by mass or less. Disclosure 4 is a sealant for liquid crystal display elements according to any of Disclosures 1 to 3, wherein the curable resin further comprises a compound having two or more (meth)acryloyl groups in one molecule other than the compound represented by formula (1-2). Disclosure 5 is a sealant for liquid crystal display elements according to any of Disclosures 1 to 4, wherein the curable resin further comprises a compound having two or more epoxy groups in one molecule. Disclosure 6 is a sealant for liquid crystal display elements according to any of Disclosures 1 to 5, wherein the compound having a total of two or more of at least one of the primary amino groups and hydrazide groups in one molecule, and a sulfonyl group bonded to an aromatic ring, has a structure represented by the following formula (4-1) or (4-2). Disclosure 7 is a sealant for liquid crystal display elements according to Disclosure 6, wherein the compound having a total of two or more of at least one of the primary amino groups and hydrazide groups in one molecule, and a sulfonyl group bonded to an aromatic ring, has a structure represented by the following formula (4-2). Disclosure 8 is a sealant for liquid crystal display elements according to any of Disclosures 1 to 7, wherein the content of the compound having a total of two or more of at least one of the primary amino groups and hydrazide groups in one molecule, and a sulfonyl group bonded to an aromatic ring, is 1.0 part by mass or more and 8.0 parts by mass or less, per 100 parts by mass of the curable resin.Disclosure 9 is a sealant for liquid crystal display elements according to any of Disclosures 1 to 8, wherein the curable resin contains a compound represented by formula (1-1), and the ratio of the content of a compound having at least two or more primary amino groups and hydrazide groups in one molecule and a sulfonyl group bonded to an aromatic ring (content of a compound having at least two or more primary amino groups and hydrazide groups in one molecule and a sulfonyl group bonded to an aromatic ring / content of the compound represented by formula (1-1)) is 0.10 or more and 1.00 or less. The present disclosure 10 relates to a curable resin composition containing a curable resin and a thermosetting agent, wherein the curable resin comprises at least one curable resin selected from the group consisting of compounds represented by the following formula (1-1) and compounds represented by the following formula (1-2), and the thermosetting agent comprises a compound having a total of two or more primary amino groups and hydrazide groups in one molecule, and a sulfonyl group bonded to an aromatic ring, and is used as a sealant for liquid crystal display elements.

[0008]

[0009] In equations (1-1) and (1-2), R １ R represents a hydrogen atom or a methyl group. ２ R represents a group represented by the following formulas (2-1), (2-2), or (2-3), ３ represents a structure derived from a dicarboxylic acid or its anhydride, X represents the ring-opening structure of a lactone, n is between 0 and 5, and Ep represents a structure derived from a bifunctional or greater epoxy compound.

[0010]

[0011] In equations (2-1) to (2-3), * represents the joining position; in equation (2-2), a is an integer between 1 and 5 (inclusive); in equation (2-3), b is an integer between 1 and 5 (inclusive); c is an integer between 1 and 5 (inclusive); and d is an integer between 1 and 5 (inclusive).

[0012]

[0013] In formulas (3-1) to (3-4), * represents a bonding site. In formula (3-1), R ４ represents a hydrogen atom or an alkyl group having 1 to 10 carbon atoms, and in formula (3-2), R ５ represents a hydrogen atom or an alkyl group having 1 to 10 carbon atoms, and in formula (3-3), R ６ represents a hydrogen atom or an alkyl group having 1 to 10 carbon atoms, and in formula (3-4), R ７ and R ８ each independently represent a hydrogen atom or an organic group having 1 to 60 carbon atoms, or R ７ and R ８ represent a structure in which they are bonded to each other.

[0014]

[0015] In formulas (4-1) and (4-2), * represents a bonding site. The present invention is described in detail below.

[0016] The present inventors have found that by using a combination of a curable resin having a specific structure and a thermosetting agent having a specific structure, a sealant for liquid crystal display elements that is excellent in all of storage stability in a heated state, adhesion to an alignment film, and low liquid crystal contamination can be obtained, and thus have completed the present invention. Hereinafter, the embodiment of the present invention or one aspect thereof will be referred to as "the present embodiment".

[0017] The sealant for a liquid crystal display element of the present embodiment contains a curable resin. The curable resin includes at least one curable resin selected from the group consisting of the compound represented by formula (1-1) and the compound represented by formula (1-2). By containing at least one curable resin selected from the group consisting of the compound represented by formula (1-1) and the compound represented by formula (1-2), the sealant for a liquid crystal display element of the present embodiment is excellent in adhesion to an alignment film and low liquid crystal contamination. Among them, the curable resin preferably includes the compound represented by formula (1-1).

[0018] In formulas (1-1) and (1-2), R ２R represents a group represented by the above formulas (2-1), (2-2), or (2-3). In particular, from the viewpoint of the adhesiveness of the resulting liquid crystal display element sealant and the flexibility of the cured product, the above R ２ It is preferable that the group is represented by the above formula (2-2), and more preferably that the group in formula (2-2) where a is 2 (ethylene group). In formulas (2-1) and (2-3), among the bond positions indicated by *, the bond position on the methylene group side is the bond position with the (meth)acryloyloxy group in formulas (1-1) and (1-2). In this specification, "(meth)acryloyl" means acryloyl or methacryloyl.

[0019] In the above formulas (1-1) and (1-2), R ３ R represents a structure derived from a dicarboxylic acid or its anhydride. ３ However, because the structure is derived from a dicarboxylic acid or its anhydride, the resulting sealant for liquid crystal display elements exhibits excellent adhesion to the alignment film. In this specification, "structure derived from a dicarboxylic acid or its anhydride" means the structure of the part of the dicarboxylic acid other than the carboxyl group, or the structure of the part of the dicarboxylic acid anhydride other than the acid anhydride group (-C(=O)-O-C(=O)-).

[0020] The structure derived from the above-mentioned dicarboxylic acid or its anhydride is preferably a chain-like hydrocarbon skeleton having 1 to 60 carbon atoms, which may have unsaturated bonds or branched structures, or a hydrocarbon skeleton including a cyclic structure. From the viewpoint of improving moisture permeability, a hydrocarbon skeleton including a cyclic structure is more preferable.

[0021] The above dicarboxylic acids specifically include, for example, 1,2-cyclohexanedicarboxylic acid, 3-methylcyclohexane-1,2-dicarboxylic acid, 4-methylcyclohexane-1,2-dicarboxylic acid, 4-cyclohexene-1,2-dicarboxylic acid, 3-methyl-4-cyclohexene-1,2-dicarboxylic acid, 3,4,5,6-tetrahydrophthalic acid, 4-methyl-4-cyclohexene-1,2-dicarboxylic acid, tetrapropenylsuccinic acid, decylsuccinic acid, tetradecylsuccinic acid, tetradecenylsuccinic acid, hexadecylsuccinic acid, isooctadecenylsuccinic acid, and butylsuccinic acid. Examples include citric acid, allyl succinic acid, 4-hexen-1,2-dicarboxylic acid, 2-dodecene-1-ylsuccinic acid, 2,2-dimethylsuccinic acid, 2-hexen-1-ylsuccinic acid, 4-methyl-4-pentene-1,2-dicarboxylic acid, 2-octenylsuccinic acid, 4,9-decadien-1,2-dicarboxylic acid, 5-norbornene-2,3-dicarboxylic acid, bicyclo[2.2.2]octo-5-ene-2,3-dicarboxylic acid, 2-(2-carboxyethyl)-3-methylmaleic acid, 7-oxabicyclo[2.2.1]hepta-5-ene-2,3-dicarboxylic acid, and phthalic acid.

[0022] From the viewpoint of further improving adhesion to the orientation film, the above R ３ It is preferable that the structure is represented by the above formulas (3-1), (3-2), (3-3), or (3-4), and more preferably by the above formulas (3-1), (3-2), or (3-3).

[0023] Examples of structures represented by formula (3-1) include structures derived from 1,2-cyclohexanedicarboxylic anhydride, 3-methylcyclohexane-1,2-dicarboxylic anhydride, etc. Examples of structures represented by formula (3-2) include structures derived from 4-cyclohexene-1,2-dicarboxylic acid, 3-methyl-4-cyclohexene-1,2-dicarboxylic anhydride, 3,4,5,6-tetrahydrophthalic anhydride, 4-methyl-4-cyclohexene-1,2-dicarboxylic anhydride, etc. Examples of structures represented by formula (3-3) include structures derived from phthalic anhydride, etc. Examples of structures represented by formula (3-4) include R７ , R ８ It may be a structure in which R is not bonded, ７ , R ８ A structure in which these are bonded together is also acceptable, but from the viewpoint of improving moisture permeability, R ７ , R ８ A structure in which the above R is bonded is preferred. ７ , R ８ Structures that are not bonded include, for example, structures derived from tetrapropenylsuccinate anhydride, decylsuccinate anhydride, tetradecylsuccinate anhydride, tetradecenylsuccinate anhydride, hexadecylsuccinate anhydride, isooctadecenylsuccinate anhydride, butylsuccinate anhydride, allylsuccinate anhydride, 4-hexen-1,2-dicarboxylic acid anhydride, 2-dodecene-1-ylsuccinate anhydride, 2,2-dimethylsuccinate anhydride, 2-hexen-1-ylsuccinate anhydride, 4-methyl-4-pentene-1,2-dicarboxylic acid anhydride, 2-octenylsuccinate anhydride, 4,9-decadien-1,2-dicarboxylic acid anhydride, etc. ７ , R ８ Examples of structures to which it is bonded include structures derived from 5-norbornene-2,3-dicarboxylic anhydride, bicyclo[2.2.2]octo-5-ene-2,3-dicarboxylic anhydride, 2-(2-carboxyethyl)-3-methylmaleic acid anhydride, 7-oxabicyclo[2.2.1]hepta-5-ene-2,3-dicarboxylic anhydride, and the like.

[0024] In formulas (1-1) and (1-2) above, X represents the ring-opening structure of a lactone. Examples of the lactones include γ-undecalactone, ε-caprolactone, γ-decalactone, σ-dodecalactone, γ-nonanolactone, γ-heptanolactone, γ-valerolactone, σ-valerolactone, β-butyrolactone, γ-butyrolactone, β-propiolactone, σ-hexanolactone, and 7-butyl-2-oxepanone. Among these, those in which the number of carbon atoms in the linear portion of the main skeleton is 5 or more and 7 or less when the ring is opened are preferred. In formulas (1-1) and (1-2) above, even if n is 0, i.e., there is no ring-opening structure of the lactone represented by X, the resulting sealant for liquid crystal display elements will have excellent adhesion to the alignment film. When n is 1 or more and 5 or less, the resulting sealant for liquid crystal display elements will have even better adhesion to the alignment film. Furthermore, the compound represented by formula (1-1) and the compound represented by formula (1-2) may each be a mixture of compounds with different numbers of X repeats, in which case n is the average value.

[0025] In formulas (1-1) and (1-2) above, Ep represents a structure derived from a bifunctional or more functional epoxy compound. Examples of epoxy compounds from which Ep is derived include bisphenol A type epoxy compounds, bisphenol F type epoxy compounds, bisphenol E type epoxy compounds, bisphenol S type epoxy compounds, resorcinol type epoxy compounds, dicyclopentadiene type epoxy compounds, naphthalene type epoxy compounds, rubber-modified epoxy compounds, glycidyl ester compounds, and the like. In particular, Ep is preferably a structure derived from a bisphenol A type epoxy compound, a bisphenol F type epoxy compound, or a bisphenol E type epoxy compound, and more preferably a structure derived from a bisphenol A type epoxy compound. In this specification, "structure derived from a bifunctional or more functional epoxy compound" means the structure of the part of the bifunctional or more functional epoxy compound other than the epoxy group.

[0026] Examples of methods for producing the compound represented by formula (1-1) include the following: a (meth)acrylic compound having a group represented by formula (2-1), (2-2), or (2-3) and a hydroxyl group, such as hydroxyalkyl (meth)acrylate, reacting with the dicarboxylic acid or its anhydride by heating and stirring in the presence of a polymerization inhibitor, and a method for reacting some of the epoxy groups of the epoxy compound by adding the bifunctional or more epoxy compound to the resulting reaction product and heating and stirring. Examples of methods for producing the compound represented by formula (1-2) include the following: a (meth)acrylic compound having a group represented by formula (2-1), (2-2), or (2-3) and a hydroxyl group, such as hydroxyalkyl (meth)acrylate, reacting with the dicarboxylic acid or its anhydride by heating and stirring in the presence of a polymerization inhibitor, and a method for reacting all of the epoxy groups of the epoxy compound by adding the bifunctional or more epoxy compound to the resulting reaction product and heating and stirring. In the methods for producing the compound represented by formula (1-1) and the compound represented by formula (1-2), the (meth)acrylic compound having the group represented by formula (2-1), (2-2), or (2-3) and a hydroxyl group may be reacted with the lactone before reacting with the dicarboxylic acid or its anhydride. In this specification, "(meth)acrylate" means acrylate or methacrylate, and "(meth)acrylic" means acrylic or methacrylic.

[0027] Examples of (meth)acrylic compounds having a group represented by the above formula (2-1), (2-2), or (2-3) and a hydroxyl group include 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, and 2-hydroxy-3-phenoxypropyl (meth)acrylate.

[0028] Examples of polymerization inhibitors include hydroquinone and p-methoxyphenol.

[0029] The preferred lower limit for the content of at least one curable resin selected from the group consisting of the compound represented by formula (1-1) and the compound represented by formula (1-2) in 100 parts by mass of the above curable resin is 5 parts by mass, and the preferred upper limit is 40 parts by mass. When the content of at least one curable resin selected from the group consisting of the compound represented by formula (1-1) and the compound represented by formula (1-2) is within this range, the resulting sealant for liquid crystal display elements will have superior storage stability under heated conditions, adhesion to alignment films, and low liquid crystal contamination. The more preferred lower limit for the content of at least one curable resin selected from the group consisting of the compound represented by formula (1-1) and the compound represented by formula (1-2) is 10 parts by mass, and the more preferred upper limit is 35 parts by mass. Furthermore, the "content of at least one curable resin selected from the group consisting of the compound represented by formula (1-1) and the compound represented by formula (1-2)" above means the content of only one of the compounds represented by formula (1-1) or formula (1-2) if only one is contained, and the total content if both are contained.

[0030] Preferably, the above-mentioned curable resin further contains compounds having two or more (meth)acryloyl groups in one molecule other than the compounds represented by formula (1-2) above (hereinafter also referred to as "other polyfunctional (meth)acrylic compounds"). By including the above-mentioned other polyfunctional (meth)acrylic compounds, the resulting sealant for liquid crystal display elements will have superior low liquid crystal contamination properties.

[0031] Examples of the above-mentioned other polyfunctional (meth)acrylic compounds include other epoxy (meth)acrylates other than the compounds represented by formula (1-2) above, (meth)acrylic acid ester compounds, urethane (meth)acrylates, etc. Among these, the above-mentioned other epoxy (meth)acrylates are preferred. In this specification, "epoxy (meth)acrylate" refers to a compound obtained by reacting all epoxy groups in an epoxy compound with (meth)acrylic acid.

[0032] Other epoxy (meth)acrylates mentioned above include, for example, those obtained by reacting an epoxy compound with (meth)acrylic acid in the presence of a basic catalyst according to a conventional method.

[0033] Examples of epoxy compounds that can be used as raw materials for synthesizing the above-mentioned other epoxy (meth)acrylates 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, 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.

[0034] Other commercially available epoxy (meth)acrylates mentioned above include, for example, epoxy (meth)acrylate manufactured by Daicel Ornex, Shin Nakamura Chemical Industry, Kyoeisha Chemical, and Nagase ChemteX. Examples of epoxy (meth)acrylates manufactured by Daicel Ornex include EBECRYL 860, EBECRYL 3200, EBECRYL 3201, EBECRYL 3412, EBECRYL 3600, EBECRYL 3700, EBECRYL 3701, EBECRYL 3702, EBECRYL 3703, EBECRYL 3800, EBECRYL 6040, EBECRYL RDX 63182, KRM 8076, etc. Examples of epoxy (meth)acrylates manufactured by Shin Nakamura Chemical Industry include EA-1010, EA-1020, EA-5323, EA-5520, EA-CHD, EMA-1020, etc. Examples of epoxy (meth)acrylates manufactured by Kyoeisha Chemical Co., Ltd. include epoxy ester M-600A, epoxy ester 40EM, epoxy ester 70PA, epoxy ester 200PA, epoxy ester 80MFA, epoxy ester 3002M, epoxy ester 3002A, epoxy ester 1600A, epoxy ester 3000M, epoxy ester 3000A, epoxy ester 200EA, epoxy ester 400EA, etc. Examples of epoxy (meth)acrylates manufactured by Nagase ChemteX Co., Ltd. include Denacol acrylate DA-141, Denacol acrylate DA-314, Denacol acrylate DA-911, etc.

[0035] Examples of the difunctional (meth)acrylic acid ester compounds listed above include 1,3-butanediol di(meth)acrylate, 1,4-butanediol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, 1,9-nonanediol di(meth)acrylate, 1,10-decanediol di(meth)acrylate, ethylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, tetraethylene glycol di(meth)acrylate, polyethylene glycol di(meth)acrylate, 2-n-butyl-2-ethyl-1,3-propanediol di(meth)acrylate, dipropylene glycol di(meth)acrylate, tripropylene glycol di(meth)acrylate, and polypropylene glycol di Examples include (meth)acrylate, neopentyl glycol di(meth)acrylate, ethylene oxide-added bisphenol A di(meth)acrylate, propylene oxide-added bisphenol A di(meth)acrylate, ethylene oxide-added bisphenol F di(meth)acrylate, dimethylol dicyclopentadienyl di(meth)acrylate, ethylene oxide-modified isocyanurate di(meth)acrylate, 2-hydroxy-3-(meth)acryloyloxypropyl(meth)acrylate, carbonate diol di(meth)acrylate, polyether diol di(meth)acrylate, polyester diol di(meth)acrylate, polycaprolactone diol di(meth)acrylate, polybutadiene diol di(meth)acrylate, and the like.

[0036] Furthermore, examples of trifunctional or more (meth)acrylic acid ester compounds among the above-mentioned compounds include trimethylolpropane tri(meth)acrylate, ethylene oxide-added trimethylolpropane tri(meth)acrylate, propylene oxide-added trimethylolpropane tri(meth)acrylate, caprolactone-modified trimethylolpropane tri(meth)acrylate, ethylene oxide-added isocyanuric acid tri(meth)acrylate, glycerin tri(meth)acrylate, propylene oxide-added glycerin tri(meth)acrylate, pentaerythritol tri(meth)acrylate, tris(meth)acryloyloxyethyl phosphate, ditrimethylolpropane tetra(meth)acrylate, pentaerythritol tetra(meth)acrylate, dipentaerythritol penta(meth)acrylate, and dipentaerythritol hexa(meth)acrylate.

[0037] 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.

[0038] 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.

[0039] 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 above-mentioned polyols include ethylene glycol, propylene glycol, glycerin, sorbitol, trimethylolpropane, carbonate diol, polyether diol, polyester diol, and polycaprolactone diol.

[0040] Examples of (meth)acrylic acid derivatives having a hydroxyl group include hydroxyalkyl mono(meth)acrylate, mono(meth)acrylate of a dihydric alcohol, mono(meth)acrylate or di(meth)acrylate of a trihydric alcohol, and epoxy(meth)acrylate. Examples of hydroxyalkyl mono(meth)acrylate include 2-hydroxyethyl(meth)acrylate, 2-hydroxypropyl(meth)acrylate, 2-hydroxybutyl(meth)acrylate, and 4-hydroxybutyl(meth)acrylate. Examples of dihydric alcohol include ethylene glycol, propylene glycol, 1,3-propanediol, 1,3-butanediol, 1,4-butanediol, and polyethylene glycol. Examples of trihydric alcohol include trimethylolethane, trimethylolpropane, and glycerin. Examples of epoxy(meth)acrylate include bisphenol A type epoxy(meth)acrylate.

[0041] Examples of commercially available urethane (meth)acrylates include those manufactured by Toagosei Co., Ltd., Daicel Ornex Co., Ltd., Negami Kogyo Co., Ltd., Shin Nakamura Chemical Industry Co., Ltd., and Kyoeisha Chemical Co., Ltd. Examples of urethane (meth)acrylates manufactured by Toagosei Co., Ltd. include M-1100, M-1200, M-1210, and M-1600. Examples of the above-mentioned urethane (meth)acrylates manufactured by Daicel Ornex include EBECRYL210, EBECRYL220, EBECRYL230, EBECRYL270, EBECRYL1290, EBECRYL2220, EBECRYL4827, EBECRYL4842, EBECRYL4858, EBECRYL5129, EBECRYL6700, EBECRYL8402, EBECRYL8803, EBECRYL8804, EBECRYL8807, and EBECRYL9260. Examples of the urethane (meth)acrylates manufactured by Negami Kogyo Co., Ltd. mentioned above include Art Resin UN-330, Art Resin SH-500B, Art Resin UN-1200TPK, Art Resin UN-1255, Art Resin UN-3320HB, Art Resin UN-7100, Art Resin UN-9000A, Art Resin UN-9000H, and the like. Examples of the above-mentioned urethane (meth)acrylates manufactured by Shin Nakamura Chemical Industry Co., Ltd. include U-2HA, U-2PHA, U-3HA, U-4HA, U-6H, U-6HA, U-6LPA, U-10H, U-15HA, U-108, U-108A, U-122A, U-122P, U-324A, U-340A, U-340P, U-1084A, U-2061BA, UA-340P, UA-4000, UA-4100, UA-4200, UA-4400, UA-5201P, UA-7100, UA-7200, UA-W2A, etc. Examples of the urethane (meth)acrylates manufactured by Kyoeisha Chemical Co., Ltd. mentioned above include AH-600, AI-600, AT-600, UA-101I, UA-101T, UA-306H, UA-306I, and UA-306T.

[0042] The preferred lower limit for the content of the other polyfunctional (meth)acrylic compound in 100 parts by mass of the above curable resin is 40 parts by mass, and the preferred upper limit is 90 parts by mass. When the content of the other polyfunctional (meth)acrylic compound is within this range, the resulting sealant for liquid crystal display elements exhibits superior storage stability under heated conditions, adhesion to alignment films, and low liquid crystal contamination. A more preferred lower limit for the content of the other polyfunctional (meth)acrylic compound is 60 parts by mass, and a more preferred upper limit is 85 parts by mass.

[0043] The above curable resin preferably further contains a compound having two or more epoxy groups in one molecule (hereinafter referred to as "polyfunctional epoxy compound"). By including the above polyfunctional epoxy compound, the resulting sealant for liquid crystal display elements exhibits superior adhesion to the alignment film.

[0044] Examples of the polyfunctional epoxy compounds mentioned above include those similar to those listed above as epoxy compounds used as raw materials for synthesizing other epoxy (meth)acrylates.

[0045] The preferred lower limit for the content of the polyfunctional epoxy compound in 100 parts by mass of the curable resin is 5 parts by mass, and the preferred upper limit is 30 parts by mass. When the content of the polyfunctional epoxy compound is within this range, the resulting sealant for liquid crystal display elements exhibits superior storage stability under heated conditions, adhesion to alignment films, and low liquid crystal contamination. A more preferred lower limit for the content of the polyfunctional epoxy compound is 10 parts by mass, and a more preferred upper limit is 20 parts by mass.

[0046] 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 65 parts by mass, and the preferred upper limit is 95 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. A more preferred lower limit for the total content of the curable resin is 70 parts by mass, and a more preferred upper limit is 90 parts by mass.

[0047] The sealant for liquid crystal display elements of this embodiment contains a thermosetting agent. The thermosetting agent includes a compound having a total of two or more primary amino groups and hydrazide groups in one molecule, and a sulfonyl group bonded to an aromatic ring (hereinafter also referred to as "the thermosetting agent according to this embodiment").

[0048] The thermosetting agent according to this embodiment has a total of two or more primary amino groups and hydrazide groups in one molecule. By having a total of two or more primary amino groups and hydrazide groups in one molecule, the sealant for liquid crystal display elements of this embodiment exhibits excellent curability and adhesion to the alignment film. In particular, it is preferable that the thermosetting agent according to this embodiment has two or more primary amino groups in one molecule. It is preferable that the thermosetting agent according to this embodiment has at least one of the primary amino groups and hydrazide groups at the end of the main chain, and it is more preferable that it has at least one of the primary amino groups and hydrazide groups at both ends of the main chain. Furthermore, from the viewpoint of storage stability, it is preferable that the total number of primary amino groups and hydrazide groups in one molecule of the thermosetting agent according to this embodiment be eight or less, more preferably four or less, and most preferably two.

[0049] The thermosetting agent according to this embodiment has a sulfonyl group bonded to an aromatic ring. Having the sulfonyl group makes the thermosetting agent according to this embodiment less likely to dissolve into liquid crystal. From the viewpoint of reactivity, it is most preferable that the thermosetting agent according to this embodiment has one sulfonyl group per molecule. Furthermore, having the aromatic ring provides the thermosetting agent according to this embodiment with excellent thermal latent properties, resulting in a sealant for liquid crystal display elements with superior storage stability under heated conditions. It is preferable that the thermosetting agent according to this embodiment has two or more aromatic rings per molecule. From the viewpoint of reactivity, it is preferable that the thermosetting agent according to this embodiment has four or fewer aromatic rings per molecule.

[0050] In the thermosetting agent according to this embodiment, examples of aromatic rings bonded to the sulfonyl group include benzene rings, naphthalene rings, anthracene rings, phenanthrene rings, and perylene rings. Furthermore, the aromatic rings may contain heteroatoms such as oxygen, nitrogen, sulfur, and phosphorus. Among these, benzene rings are preferred.

[0051] The thermosetting agent according to this embodiment preferably has a structure represented by the above formula (4-1) or (4-2). By having the thermosetting agent according to this embodiment have a structure represented by the above formula (4-1) or (4-2), the sealant for liquid crystal display elements of this embodiment will have superior storage stability and low liquid crystal contamination properties. In particular, from the viewpoint of adhesion to the alignment film, it is more preferable that the thermosetting agent according to this embodiment has a structure represented by the above formula (4-2).

[0052] Examples of thermosetting agents according to this embodiment include, specifically, 4,4'-diaminodiphenyl sulfone, bis(4-(3-aminophenoxy)phenyl) sulfone, bis(3-aminophenyl) sulfone, bis(3-amino-4-hydroxyphenyl) sulfone, and 4,4'-sulfonylbisbenzhydrazide. Among these, bis(3-amino-4-hydroxyphenyl) sulfone is preferred.

[0053] The preferred lower limit for the content of the thermosetting agent according to this embodiment per 100 parts by mass of the curable resin is 1.0 part by mass, and the preferred upper limit is 8.0 parts by mass. When the content of the thermosetting agent according to this embodiment per 100 parts by mass of the curable resin is 1.0 part by mass or more, the resulting sealant for liquid crystal display elements will have superior curability and adhesion. When the content of the thermosetting agent according to this embodiment per 100 parts by mass of the curable resin is 8.0 parts by mass or less, the resulting sealant for liquid crystal display elements will have superior low liquid crystal contamination and storage stability under heated conditions. The more preferred lower limit for the content of the thermosetting agent according to this embodiment per 100 parts by mass of the curable resin is 2.0 parts by mass, the more preferred upper limit is 7.5 parts by mass, the still preferred lower limit is 2.5 parts by mass, and the still preferred upper limit is 7.0 parts by mass. Furthermore, when the curable resin contains the compound represented by formula (1-1), the preferred lower limit of the ratio of the content of the thermosetting agent according to this embodiment to the content of the compound represented by formula (1-1) (content of the thermosetting agent according to this embodiment / content of the compound represented by formula (1-1)) is 0.10, and the preferred upper limit is 1.00. When the ratio of the content of the thermosetting agent according to this embodiment to the content of the compound represented by formula (1-1) is 0.10 or higher, the resulting sealant for liquid crystal display elements will have superior curability and adhesion. When the ratio of the content of the thermosetting agent according to this embodiment to the content of the compound represented by formula (1-1) is 1.00 or lower, the resulting sealant for liquid crystal display elements will have superior low liquid crystal contamination and storage stability under heated conditions. A more preferred lower limit of the ratio of the content of the thermosetting agent according to this embodiment to the content of the compound represented by formula (1-1) is 0.15, a more preferred upper limit is 0.80, an even more preferred lower limit is 0.16, and an even more preferred upper limit is 0.75.

[0054] The sealing agent for liquid crystal display elements of this embodiment preferably further contains a photopolymerization initiator. Examples of the photopolymerization initiator include benzophenone compounds, acetophenone compounds, acylphosphine oxide compounds, titanocene compounds, oxime ester compounds, benzoin ether compounds, thioxanthone compounds, and the like. Specifically, examples of the photopolymerization initiator include 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, 2-methyl-1-(4-methyl Examples include 1-(4-(2-hydroxyethoxy)-phenyl)-2-hydroxy-2-methyl-1-propan-1-one, 1-(4-(phenylthio)phenyl)-1,2-octanedione 2-(O-benzoyl oxime), 2-(acetoxyimino)-1-(4-(4-(2-hydroxyethoxy)phenylthio)phenyl)propan-1-one, and 2,4,6-trimethylbenzoyldiphenylphosphine oxide.

[0055] The preferred lower limit for the content of the above-mentioned photopolymerization initiator is 0.5 parts by mass and the preferred upper limit is 10 parts by mass per 100 parts by mass of the above-mentioned curable resin. When the content of the above-mentioned photopolymerization initiator is within this range, the resulting sealant for liquid crystal display elements will have superior storage stability and photocurability while suppressing the occurrence of liquid crystal contamination. A more preferred lower limit for the content of the above-mentioned photopolymerization initiator is 1 part by mass and a more preferred upper limit is 7 parts by mass.

[0056] The sealant for liquid crystal display elements of this embodiment may contain fillers for purposes such as improving viscosity, improving adhesion through stress dispersion effect, improving coefficient of thermal expansion, and improving moisture resistance of the cured product.

[0057] Inorganic or organic fillers can be used as the above-mentioned fillers. Examples of inorganic fillers 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, and calcium silicate. Examples of organic fillers include polyester microparticles, polyurethane microparticles, vinyl polymer microparticles, and acrylic polymer microparticles.

[0058] 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 50 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 15 parts by mass, and a more preferred upper limit is 40 parts by mass.

[0059] The liquid crystal display element sealant of this embodiment may contain a silane coupling agent. The silane coupling agent mainly serves as an adhesive aid for good adhesion between the liquid crystal display element sealant and the substrate, etc.

[0060] Suitable silane coupling agents include, for example, 3-aminopropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, and 3-isocyanatetopropyltrimethoxysilane. These are excellent at improving adhesion to substrates and can suppress the outflow of curable resin into the liquid crystal by chemically bonding with the curable resin. Among these, 3-glycidoxypropyltrimethoxysilane is preferred. The silane coupling agents may be used alone or in combination of two or more.

[0061] 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. When the silane coupling agent content is within this range, the resulting sealant for liquid crystal display elements exhibits 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.

[0062] The sealant for liquid crystal display elements of this embodiment may further contain, if necessary, additives such as a thermal polymerization initiator, a curing accelerator, a light-shielding agent, a stress-relaxing agent, a reactive diluent, a thixotrope, a spacer, a curing accelerator, an antifoaming agent, a leveling agent, or a polymerization inhibitor.

[0063] 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 thermosetting agent, and a photopolymerization initiator, etc., which may be added as needed, using a mixer. Examples of such mixers include homodispers, homomixers, universal mixers, planetary mixers, kneaders, and three-roll mixers.

[0064] By incorporating conductive fine particles into the sealant for liquid crystal display elements of this embodiment, a conductive material can be manufactured. Examples of conductive fine particles include metal balls and resin fine particles with a conductive metal layer formed on their surface. Among these, resin fine particles with a conductive metal layer formed on their surface are preferred because the excellent elasticity of the resin fine particles allows for conductive connection without damaging transparent substrates or the like.

[0065] As a liquid crystal display element obtained using the sealant for liquid crystal display elements of this embodiment, a liquid crystal display element with a narrow bezel design is preferred. Specifically, it is preferable that the width of the frame portion around the liquid crystal display area is 2 mm or less. Furthermore, it is preferable that the application width of the sealant for liquid crystal display elements of this embodiment when manufacturing the above-mentioned liquid crystal display element is 1 mm or less.

[0066] The liquid crystal display element sealant of this embodiment can be suitably used in the manufacture of liquid crystal display elements by the liquid crystal drop method. Examples of methods for manufacturing the liquid crystal display element by the liquid crystal drop method include the following: First, the liquid crystal display element sealant of this embodiment is applied to a substrate by screen printing, dispenser coating, etc., to form a frame-shaped seal pattern. Next, while the liquid crystal display element sealant of this embodiment is still uncured, tiny droplets of liquid crystal are dropped onto the entire surface within the frame of the seal pattern, and another substrate is immediately placed on top. After that, a liquid crystal display element can be obtained by heating and curing the sealant. Alternatively, before heating and curing the sealant, the sealant may be partially cured by irradiating the seal pattern portion with light such as ultraviolet light.

[0067] The use of a curable resin composition containing a curable resin and a thermosetting agent as a sealant for liquid crystal display elements is also one embodiment of the present invention. The curable resin comprises at least one curable resin selected from the group consisting of compounds represented by the following formula (1-1) and compounds represented by the following formula (1-2), and the thermosetting agent comprises a compound having a total of two or more primary amino groups and hydrazide groups in one molecule, and a sulfonyl group bonded to an aromatic ring. 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 embodiment.

[0068] According to the present invention, it is possible to provide a sealant for liquid crystal display elements that is excellent in storage stability under heated conditions, adhesion to alignment films, 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.

[0069] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples.

[0070] (Preparation of curable resin A) 116 parts by mass of 2-hydroxyethyl acrylate, 168 parts by mass of 4-methylcyclohexane-1,2-dicarboxylic acid anhydride, and 0.05 parts by mass of hydroquinone as a polymerization inhibitor were added to a reaction flask, and the mixture was stirred at 90°C for 5 hours using a mantle heater. Next, 340 parts by mass of bisphenol A diglycidyl ether was added to the resulting reaction mixture, and then 0.5 parts by mass of triphenylphosphine was added, and the mixture was stirred at 110°C for 5 hours to obtain curable resin A. １ H-NMR and １３ C-NMR determined that the curable resin A is R in formula (1-1) above. １ is a hydrogen atom, R ２ is an ethylene group, R ３ The structure is represented by the above formula (3-1) (R ４ We confirmed that the compound has a structure in which n is 0 and Ep is derived from bisphenol A diglycidyl ether (where n is a methyl group).

[0071] (Preparation of curable resin B) Curable resin B was obtained in the same manner as described in "(Preparation of curable resin A)" above, except that 116 parts by mass of 2-hydroxyethyl acrylate was replaced with 222 parts by mass of 2-hydroxy-3-phenoxypropyl acrylate. １ H-NMR and １３ C-NMR determined that the curable resin B is R in formula (1-1) above. １ is a hydrogen atom, R ２ is a phenoxymethylethylene group, R ３ The structure is represented by the above formula (3-1) (R ４ We confirmed that the compound has a structure in which n is 0 and Ep is derived from bisphenol A diglycidyl ether (where n is a methyl group).

[0072] (Preparation of curable resin C) Curable resin C was obtained in the same manner as described above in "(Preparation of curable resin A)," except that 116 parts by mass of 2-hydroxyethyl acrylate was replaced with 130 parts by mass of 2-hydroxypropyl acrylate. １ H-NMR and １３ C-NMR determines that the curable resin C is R in formula (1-1) above. １ is a hydrogen atom, R ２is a methylethylene group, R ３ The structure is represented by the above formula (3-1) (R ４ We confirmed that the compound has a structure in which n is 0 and Ep is derived from bisphenol A diglycidyl ether (where n is a methyl group).

[0073] (Preparation of curable resin D) Curable resin D was obtained in the same manner as described above in "(Preparation of curable resin A)", except that 116 parts by mass of 2-hydroxyethyl acrylate was replaced with 130 parts by mass of 2-hydroxyethyl methacrylate. １ H-NMR and １３ C-NMR determined that the curable resin D is R in formula (1-1) above. １ is a methyl group, R ２ is an ethylene group, R ３ The structure is represented by the above formula (3-1) (R ４ We confirmed that the compound has a structure in which n is 0 and Ep is derived from bisphenol A diglycidyl ether (where n is a methyl group).

[0074] (Preparation of curable resin E) Curable resin E was obtained in the same manner as described above in "(Preparation of curable resin A)", except that 340 parts by mass of bisphenol A diglycidyl ether was replaced with 268 parts by mass of dicyclopentadiene diglycidyl ether. １ H-NMR and １３ C-NMR determined that the curable resin E is R in formula (1-1) above. １ is a hydrogen atom, R ２ is an ethylene group, R ３ The structure is represented by the above formula (3-1) (R ４ We confirmed that the compound has a structure in which n is 0 and Ep is derived from dicyclopentadiene diglycidyl ether (where n is a methyl group).

[0075] (Preparation of curable resin F) Curable resin F was obtained in the same manner as described in "(Preparation of curable resin A)" above, except that 168 parts by mass of 4-methylcyclohexane-1,2-dicarboxylic acid anhydride was replaced with 154 parts by mass of 1,2-cyclohexanedicarboxylic acid anhydride. １ H-NMR and １３ C-NMR determines that the curable resin F is R in formula (1-1) above. １ is a hydrogen atom, R２ is an ethylene group, R ３ The structure is represented by the above formula (3-1) (R ４ We confirmed that the compound has a structure in which n is 0 (where n is a hydrogen atom) and Ep is derived from bisphenol A diglycidyl ether.

[0076] (Preparation of curable resin G) Curable resin G was obtained in the same manner as described in "(Preparation of curable resin A)" above, except that 168 parts by mass of 4-methylcyclohexane-1,2-dicarboxylic acid anhydride was replaced with 166 parts by mass of 4-cyclohexene-1,2-dicarboxylic acid anhydride. １ H-NMR and １３ C-NMR determined that the curable resin G is R in formula (1-1) above. １ is a hydrogen atom, R ２ is an ethylene group, R ３ The structure is represented by the above formula (3-2) (R ５ We confirmed that the compound has a structure in which n is 0 (where n is a hydrogen atom) and Ep is derived from bisphenol A diglycidyl ether.

[0077] (Preparation of curable resin H) Curable resin H was obtained in the same manner as described in "(Preparation of curable resin A)" above, except that 168 parts by mass of 4-methylcyclohexane-1,2-dicarboxylic acid anhydride was replaced with 148 parts by mass of phthalic anhydride. １ H-NMR and １３ C-NMR determined that the curable resin H is R in formula (1-1) above. １ is a hydrogen atom, R ２ is an ethylene group, R ３ The structure is represented by the above formula (3-3) (R ６ We confirmed that the compound has a structure in which n is 0 (where n is a hydrogen atom) and Ep is derived from bisphenol A diglycidyl ether.

[0078] (Preparation of curable resin I) 116 parts by mass of 2-hydroxyethyl acrylate, 114 parts by mass of ε-caprolactone, and 0.5 parts by mass of hydroquinone as a polymerization inhibitor were added to a reaction flask and stirred at 90°C for 5 hours using a mantle heater. Then, 168 parts by mass of 4-methylcyclohexane-1,2-dicarboxylic acid anhydride were added and stirred for a further 5 hours. Next, 340 parts by mass of bisphenol A diglycidyl ether was added to the resulting reaction product, and then 0.5 parts by mass of triphenylphosphine was added and stirred at 110°C for 5 hours to obtain curable resin I. １ H-NMR and １３ C-NMR determines that the curable resin I is R in formula (1-1) above. １ is a hydrogen atom, R ２ is an ethylene group, R ３ The structure is represented by the above formula (3-1) (R ４ It was confirmed that the compound is a structure derived from bisphenol A diglycidyl ether, with X being the ring-opened structure of ε-caprolactone, n being 1.0 (average value), and Ep being the structure derived from bisphenol A diglycidyl ether.

[0079] (Preparation of curable resin J) Curable resin J was obtained in the same manner as described above in "(Preparation of curable resin A)," except that the amount of ε-caprolactone used was changed to 456 parts by mass. １ H-NMR and １３ C-NMR determined that the curable resin J is R in formula (1-1) above. １ is a hydrogen atom, R ２ is an ethylene group, R ３ The structure is represented by the above formula (3-1) (R ４ It was confirmed that the compound is a structure derived from bisphenol A diglycidyl ether, with X being the ring-opened structure of ε-caprolactone, n being 4.0 (average value), and Ep being the structure derived from bisphenol A diglycidyl ether.

[0080] (Preparation of Curable Resin K) To a reaction flask, 232 parts by mass of 2-hydroxyethyl acrylate, 336 parts by mass of 4-methylcyclohexane-1,2-dicarboxylic anhydride, and 0.1 parts by mass of hydroquinone as a polymerization inhibitor were added, and the mixture was stirred at 90°C for 5 hours using a mantle heater. Next, 340 parts by mass of bisphenol A diglycidyl ether was added to the obtained reaction product, 0.5 parts by mass of triphenylphosphine was further added, and the mixture was stirred at 110°C for 5 hours, thereby obtaining curable resin K. １ 1H-NMR and １３ 13C-NMR confirmed that, in the above formula (1-2), curable resin K is a compound in which R １ is a hydrogen atom, R ２ is an ethylene group, R ３ is a structure represented by the above formula (3-1) (wherein R ４ is a methyl group), n is 0, and Ep is a structure derived from bisphenol A diglycidyl ether.

[0081] (Preparation of Curable Resin L) To a reaction flask, 232 parts by mass of 2-hydroxyethyl acrylate, 340 parts by mass of bisphenol A diglycidyl ether, 0.5 parts by mass of hydroquinone as a polymerization inhibitor, and 0.5 parts by mass of triphenylphosphine were added, and the mixture was stirred at 110°C for 5 hours, thereby obtaining curable resin L. １ 1H-NMR and １３ 13C-NMR confirmed that curable resin L is a compound represented by the following formula (5).

[0082]

[0083] (Preparation of partially acrylic-modified biphenyl ether type epoxy compound) 1000 parts by mass of biphenyl ether type epoxy compound (manufactured by Nippon Steel Chemical & Material Co., Ltd., "YSLV80DE"), 229 parts by mass of acrylic acid, 2 parts by mass of p-methoxyphenol as a polymerization inhibitor, and 2 parts by mass of triethylamine as a reaction catalyst were reacted at 90°C with reflux stirring while supplying air for 5 hours. 100 parts by mass of the resulting reaction product was filtered through a column packed with 10 parts by mass of a natural compound of quartz and kaolin (manufactured by Hoffmann Minerals Co., Ltd., "Silicin V85") to adsorb ionic impurities in the reaction product, thereby obtaining a partially acrylic-modified biphenyl ether type epoxy compound.

[0084] (Examples 1-15, Comparative Examples 1-7) Following the mixing ratios listed in Tables 1-4, each material was mixed using a planetary agitator (Sinky Co., Ltd., "Awatori Rentaro"), and then further mixed using a three-roll mixer to prepare the liquid crystal display element sealants for Examples 1-15 and Comparative Examples 1-7.

[0085] The materials used in the examples and comparative examples are as follows: <Curable Resins> (Compounds represented by formula (1-1)) ・Curable resin A: Compound obtained in "(Preparation of curable resin A)" above ・Curable resin B: Compound obtained in "(Preparation of curable resin B)" above ・Curable resin C: Compound obtained in "(Preparation of curable resin C)" above ・Curable resin D: Compound obtained in "(Preparation of curable resin D)" above ・Curable resin E: Compound obtained in "(Preparation of curable resin E)" above ・Curable resin F: Compound obtained in "(Preparation of curable resin F)" above ・Curable resin G: Compound obtained in "(Preparation of curable resin G)" above ・Curable resin H: Compound obtained in "(Preparation of curable resin H)" above ・Curable resin I: Compound obtained in "(Preparation of curable resin I)" above ・Curable resin J: Compound obtained in "(Preparation of curable resin J)" above (Compounds represented by formula (1-2)) ・Curable resin K: Compound obtained in "(Preparation of curable resin K)" above (Other polyfunctional (meth)acrylic compounds) ・Bisphenol A type epoxy acrylate: EBECRYL3700 (manufactured by Daicel Ornex Co., Ltd.) ・Curable resin L: Compound obtained in "(Preparation of curable resin L)" above (Other partially (meth)acrylic modified epoxy compounds) ・Partially acrylic modified biphenyl ether type epoxy compound: Compound obtained in "(Preparation of partially acrylic modified biphenyl ether type epoxy compound)" above (Polyfunctional epoxy compounds) ・Bisphenol F type epoxy compound: EPICLON EXA-830CRP (manufactured by DIC Corporation) <Thermosetting agent> (Thermosetting agent according to this embodiment) ・Bis(3-amino-4-hydroxyphenyl) sulfone (manufactured by Tokyo Chemical Industry Co., Ltd.) ・Bis(3-aminophenyl) sulfone (manufactured by Tokyo Chemical Industry Co., Ltd.) (Other thermosetting agents) ・Malonic acid dihydrazide: MDH (manufactured by Mitsubishi Gas Chemical Next Co., Ltd.) • Amine adduct compound: ADEKA Hardener EH-5057PK (manufactured by ADEKA Corporation) • 4,4'-diaminodiphenyl ketone (manufactured by Tokyo Chemical Industry Co., Ltd.) • 4,4'-diaminodiphenyl ether (manufactured by Tokyo Chemical Industry Co., Ltd.) <Photoradical polymerization initiator> • 1-(4-(phenylthio)phenyl)-1,2-Octanedione 2-(O-benzoyl oxime): IRGACURE OXE01 (BASF) <Inorganic filler> ・Silica: Sunseal SP-07M (Tokuyama) <Silane coupling agent> ・3-Glycidoxypropyltrimethoxysilane: Sila Ace S-510 (Chisso)

[0086] <Evaluation> The following evaluation was performed on the obtained sealant for liquid crystal display elements. The results are shown in Tables 1 to 4.

[0087] (Storage Stability) The viscosity of the obtained sealant for liquid crystal display elements was measured at its initial viscosity immediately after manufacturing, its viscosity after storage at 25°C for one week after manufacturing, and its viscosity after storage at 40°C for one week after manufacturing. The viscosity increase rate was defined as (viscosity after storage) / (initial viscosity), and a viscosity increase rate of less than 1.25 was marked as "○", a rate of 1.25 or more and less than 1.30 was marked as "△", and a rate of 1.30 or more was marked as "×". The storage stability at 25°C and 40°C was evaluated. The viscosity of the sealant for liquid crystal display elements was measured using an E-type viscometer (BROK FIELD, "DV-III") at 25°C with a rotation speed of 1.0 rpm.

[0088] (Adhesion to Alignment Film) An alignment film-coated substrate was prepared by spin-coating an imide resin onto an ITO thin film-coated glass substrate, pre-baking it at 80°C, and then firing it at 230°C. SE7492 (manufactured by Nissan Chemical Corporation) was used as the imide resin. Polydivinylbenzene particles with an average particle size of 4 μm (Sekisui Chemical Co., Ltd., "Micropearl SP-204") were added as a gap agent to the obtained liquid crystal display element sealant at a content of 1% by mass, and the mixture was uniformly dispersed using a planetary stirrer. Next, the liquid crystal display element sealant with the gap agent added was minutely dropped onto the alignment film of the alignment film-coated substrate. Another alignment film-coated substrate was bonded in a cross shape to the liquid crystal display element-coated substrate with the liquid crystal display element sealant dropped onto it, via the liquid crystal display element sealant, and irradiated using a metal halide lamp at a wavelength of 365 nm and an irradiance of 100 mW / cm. ２A test piece was obtained by irradiating with ultraviolet rays for 30 seconds, followed by heating at 120°C for 1 hour. For the obtained test piece, when the edge portion of the substrate was pressed in at a speed of 5 mm / min using a metal cylinder with a radius of 5 mm, the strength at which substrate peeling occurred (peel strength) was measured using Autograph AGS-X (manufactured by Shimadzu Corporation). Adhesion to the alignment film was evaluated according to the following criteria: when the value obtained by dividing the obtained measured value (kgf) by the seal diameter (cm) was 2.5 kgf / cm or more, the result was rated "○"; when it was more than 2.0 kgf / cm and less than 2.5 kgf / cm, the result was rated "△"; when it was 2.0 kgf / cm or less, the result was rated "×".

[0089] (Low liquid crystal contamination) 1 part by mass of spacer fine particles with an average particle diameter of 7 µm ("Micropearl SI-H050", manufactured by Sekisui Chemical Co., Ltd.) was dispersed in 100 parts by mass of the obtained sealant for liquid crystal display elements, filled into a syringe, and defoamed using a centrifugal defoamer ("Awatorn AW-1", manufactured by Musashi Engineering Co., Ltd.). The defoamed sealant for liquid crystal display elements was applied in a frame shape to one of two glass substrates each provided with an alignment film and an ITO thin film using a dispenser under the following conditions: nozzle diameter 0.4 mmφ, nozzle gap 42 µm, syringe discharge pressure 100 to 400 kPa, application speed 60 mm / sec. For the alignment film, RB-005 manufactured by Nissan Chemical Corporation was used, and polarized light with a wavelength of 254 nm at 300 mJ / cm ２ was irradiated to perform alignment treatment. At this time, the discharge pressure was adjusted so that the line width of the sealant for liquid crystal display elements after bonding the substrates was 0.7 mm. Subsequently, fine droplets of negative-type liquid crystal ("JC-7129XX", manufactured by Merck) were dropped and applied over the entire inner surface of the frame of the sealant for liquid crystal display elements on the substrate coated with the sealant for liquid crystal display elements, and the other substrate was bonded under vacuum. For the bonded substrates, the sealant for liquid crystal display elements portion was irradiated with light from a metal halide lamp at a wavelength of 365 nm and an illuminance of 100 mW / cm ２Liquid crystal display elements were fabricated by irradiating them with ultraviolet light for 30 seconds and then heating them at 120°C for 1 hour. The obtained liquid crystal display elements were examined for orientation disorder (display unevenness) using a polarizing microscope (Keyence Corporation, "VHX-5000"). Orientation disorder was judged from the color unevenness of the display area, and the low liquid crystal contamination performance was evaluated by marking "○" if no display unevenness was observed in the liquid crystal display element, and "×" if display unevenness was observed.

[0090]

[0091]

[0092]

[0093]

[0094] According to the present invention, it is possible to provide a sealant for liquid crystal display elements that is excellent in storage stability under heated conditions, adhesion to alignment films, 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. A sealant for liquid crystal display elements comprising a curable resin and a thermosetting agent, wherein the curable resin comprises at least one curable resin selected from the group consisting of compounds represented by the following formula (1-1) and compounds represented by the following formula (1-2), and the thermosetting agent comprises a compound having a total of two or more primary amino groups and hydrazide groups in one molecule, and a sulfonyl group bonded to an aromatic ring. In equations (1-1) and (1-2), R １ R represents a hydrogen atom or a methyl group. ２ R represents a group represented by the following formulas (2-1), (2-2), or (2-3), ３ represents a structure derived from a dicarboxylic acid or its anhydride, X represents the ring-opening structure of a lactone, n is between 0 and 5, and Ep represents a structure derived from a bifunctional or greater epoxy compound. In equations (2-1) to (2-3), * represents the joining position; in equation (2-2), a is an integer between 1 and 5 (inclusive); in equation (2-3), b is an integer between 1 and 5 (inclusive); c is an integer between 1 and 5 (inclusive); and d is an integer between 1 and 5 (inclusive).

2. In the above formulas (1-1) and (1-2), R ３ is a structure represented by the following formula (3-1), (3-2), (3-3), or (3-4). The sealant for a liquid crystal display element according to claim 1. In formulas (3-1) to (3-4), * represents a bonding position, and in formula (3-1), R ４ represents a hydrogen atom or an alkyl group having 1 to 10 carbon atoms, and in formula (3-2), R ５ represents a hydrogen atom or an alkyl group having 1 to 10 carbon atoms, and in formula (3-3), R ６ represents a hydrogen atom or an alkyl group having 1 to 10 carbon atoms, and in formula (3-4), R ７ and R ８ each independently represent a hydrogen atom or an organic group having 1 to 60 carbon atoms, or alternatively, R ７ , R ８ represents a structure in which are bonded to each other.

3. The sealant for liquid crystal display elements according to claim 1 or 2, wherein the content of at least one curable resin selected from the group consisting of the compound represented by formula (1-1) and the compound represented by formula (1-2) in 100 parts by mass of the curable resin is 5 parts by mass or more and 40 parts by mass or less.

4. The sealant for liquid crystal display elements according to any one of claims 1 to 3, wherein the curable resin further comprises a compound having two or more (meth)acryloyl groups in one molecule other than the compound represented by formula (1-2).

5. The sealant for liquid crystal display elements according to any one of claims 1 to 4, wherein the curable resin further comprises a compound having two or more epoxy groups in one molecule.

6. A sealant for liquid crystal display elements according to any one of claims 1 to 5, wherein a compound having a total of two or more primary amino groups and hydrazide groups in one molecule, and a sulfonyl group bonded to an aromatic ring, has a structure represented by the following formula (4-1) or (4-2). In equations (4-1) and (4-2), * indicates the bonding position.

7. The sealant for liquid crystal display elements according to claim 6, wherein a compound having a total of two or more primary amino groups and hydrazide groups in one molecule, and a sulfonyl group bonded to an aromatic ring, has the structure represented by formula (4-2) above.

8. The sealant for liquid crystal display elements according to any one of claims 1 to 7, wherein the content of a compound having at least two primary amino groups and hydrazide groups in a single molecule, and a sulfonyl group bonded to an aromatic ring, is 1.0 part by mass or more and 8.0 parts by mass or less, per 100 parts by mass of the curable resin.

9. The sealant for liquid crystal display elements according to any one of claims 1 to 8, wherein the curable resin contains a compound represented by formula (1-1), and the ratio of the content of a compound having a total of two or more primary amino groups and hydrazide groups in one molecule and a sulfonyl group bonded to an aromatic ring (content of a compound having a total of two or more primary amino groups and hydrazide groups in one molecule and a sulfonyl group bonded to an aromatic ring / content of the compound represented by formula (1-1)) is 0.10 or more and 1.00 or less.

10. Use of a curable resin composition containing a curable resin and a thermosetting agent, wherein the curable resin comprises at least one curable resin selected from the group consisting of compounds represented by the following formula (1-1) and compounds represented by the following formula (1-2), and the thermosetting agent comprises a compound having a total of two or more primary amino groups and hydrazide groups in one molecule, and a sulfonyl group bonded to an aromatic ring, as a sealant for liquid crystal display elements. In equations (1-1) and (1-2), R １ R represents a hydrogen atom or a methyl group. ２ R represents a group represented by the following formulas (2-1), (2-2), or (2-3), ３ represents a structure derived from a dicarboxylic acid or its anhydride, X represents the ring-opening structure of a lactone, n is between 0 and 5, and Ep represents a structure derived from a bifunctional or greater epoxy compound. In equations (2-1) to (2-3), * represents the joining position; in equation (2-2), a is an integer between 1 and 5 (inclusive); in equation (2-3), b is an integer between 1 and 5 (inclusive); c is an integer between 1 and 5 (inclusive); and d is an integer between 1 and 5 (inclusive).

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