Sealing agent for liquid crystal display element and liquid crystal display element

Abstract

The present invention aims to provide a sealant for liquid crystal display elements, which is excellent in storage stability, adhesion, and low liquid crystal contamination. In addition, the present invention aims to provide a liquid crystal display element using the sealant for liquid crystal display elements. The sealant for liquid crystal display elements of the present invention contains a curable resin and a thermal curing agent, and the thermal curing agent contains an adduct of an amine compound having an amino equivalent of 30 or less and an epoxy compound.

Description

TECHNICAL FIELD

[0001] The present application relates to a sealant for liquid crystal display elements, which is excellent in storage stability, adhesiveness, and low liquid crystal contamination. In addition, the present application relates to a liquid crystal display element using the sealant for liquid crystal display elements. BACKGROUND

[0002] In recent years, as a manufacturing method of a liquid crystal display element such as a liquid crystal display unit, from the viewpoint of shortening of production cycle time, optimization of the amount of liquid crystal used, and the like, a liquid crystal dropping method called a dropping process using a sealant disclosed in Patent Literature 1, Patent Literature 2 is used.

[0003] In the dropping process, first, a frame-shaped seal pattern is formed on one of two substrates with electrodes by a dispensing method. Next, a minute drop of liquid crystal is dropped into the frame of the seal pattern in a state where the sealant is not cured, and after another substrate is overlapped under vacuum, the sealant is cured, and a liquid crystal display element is produced. The dropping process is currently mainstream as a manufacturing method of a liquid crystal display element.

[0004] However, in the present time when various mobile devices with liquid crystal panels such as mobile phones, portable game machines are popularized, miniaturization of the devices is the most required problem. As a method of miniaturization of the devices, a narrow frame of a liquid crystal display portion can be cited, and for example, a design in which the position of a seal portion is disposed under a black matrix (hereinafter, also referred to as a narrow frame design) is performed.

[0005] PRIOR ART DOCUMENTS

[0006] PATENT LITERATURE

[0007] Patent Literature 1: Japanese Patent Application Laid-Open No. 2001-133794

[0008] Patent Literature 2: International Publication No. 02 / 092718 SUMMARY

[0009] PROBLEMS TO BE SOLVED BY THE INVENTION

[0010] In the narrow frame design, since the sealant is disposed directly under the black matrix, if the dropping process is performed, there is a problem that light irradiated when the sealant is photocured is blocked, and the light hardly reaches the inside of the sealant, and the curing of the conventional sealant becomes insufficient. If the curing of the sealant becomes insufficient like this, there is a problem that an uncured sealant component is eluted into the liquid crystal, and liquid crystal contamination easily occurs. In particular, in recent years, with high polarization of the liquid crystal, even in the case where a conventional sealant which has not been a problem is used, liquid crystal contamination sometimes occurs, and further low liquid crystal contamination is required for the sealant.

[0011] In a case where it is difficult to photocure the sealant, it is considered to cure it by heating, and as a method for curing the sealant by heating, an operation of incorporating a thermal curing agent in the sealant is performed. In addition, in a narrow frame design, the sealant is also disposed on an orientation film, and thus a sealant for liquid crystal display elements which is excellent not only in adhesion to a substrate but also in adhesion to an orientation film is required. However, in a case where a thermal curing agent having high reactivity is used in order to improve the curability and adhesion of the sealant, sometimes the obtained sealant has poor storage stability, or liquid crystal contamination occurs.

[0012] An object of the present application is to provide a sealant for liquid crystal display elements which is excellent in storage stability, adhesion, and low liquid crystal contamination. Another object of the present application is to provide a liquid crystal display element using the sealant for liquid crystal display elements.

[0013] Means for solving the problem

[0014] Disclosed is a sealant for liquid crystal display elements, which contains a curable resin and a thermal curing agent, the thermal curing agent comprising an adduct of an amine compound having an amino equivalent of 30 or less and an epoxy compound.

[0015] Disclosed is a sealant for liquid crystal display elements according to the present application, wherein the amine compound having an amino equivalent of 30 or less is at least any one of hydrazine and carbazide.

[0016] Disclosed is a sealant for liquid crystal display elements according to the present application, wherein the adduct of the amine compound having an amino equivalent of 30 or less and the epoxy compound is in a solid state at 25°C.

[0017] Disclosed is a sealant for liquid crystal display elements according to the present application, wherein the epoxy compound is an epoxy compound having a structure derived from a compound having a phenolic hydroxyl group.

[0018] Disclosed is a liquid crystal display element having a cured product of the sealant for liquid crystal display elements according to the present application.

[0019] Hereinafter, the present application will be described in detail.

[0020] The present inventors have studied to improve the storage stability and the low liquid crystal contamination property of a sealant for liquid crystal display elements by using an amine adduct of an epoxy compound as a thermal curing agent. However, the resulting sealant for liquid crystal display elements sometimes has poor adhesion (particularly to an alignment film). Thus, the present inventors have made intensive studies, and as a result, have found that by using an adduct of an amine compound having an amino equivalent of 30 or less and an epoxy compound as a thermal curing agent, a sealant for liquid crystal display elements having excellent storage stability, adhesion, and low liquid crystal contamination property can be obtained, and the present invention has been completed as a result.

[0021] The sealant for liquid crystal display elements of the present invention contains a thermal curing agent.

[0022] The above-mentioned thermal curing agent contains an adduct of an amine compound having an amino equivalent of 30 or less and an epoxy compound (hereinafter, also referred to as "adduct of the present invention").

[0023] By containing the adduct of the present invention, the sealant for liquid crystal display elements of the present invention has excellent storage stability, adhesion, and low liquid crystal contamination property.

[0024] Note that in the present specification, the above-mentioned "amine compound" refers to an amine compound, a hydrazine-based compound, a hydrazide compound, and the like having an amino group. In addition, the above-mentioned "amino equivalent" refers to a value calculated from (molecular weight of the amine compound) / (number of amino groups in 1 molecule of the amine compound), and the above-mentioned "number of amino groups" refers to the number of nitrogen atoms constituting an amino group. For example, for 1 hydrazine group (-NHNH2 group), the number of amino groups is calculated as 2.

[0025] The adduct of the present invention has a structure from an amine compound having an amino equivalent of 30 or less and a structure from an epoxy compound.

[0026] The preferred lower limit of the amino equivalent of the above-mentioned amine compound having an amino equivalent of 30 or less which is the source of the adduct of the present invention is 15, and the preferred upper limit thereof is 25. By making the amino equivalent of the above-mentioned amine compound having an amino equivalent of 30 or less be within this range, the effect of making the resulting sealant for liquid crystal display elements have excellent storage stability, adhesion, and low liquid crystal contamination property becomes more excellent. The more preferred lower limit of the amino equivalent of the above-mentioned amine compound having an amino equivalent of 30 or less is 16, and the more preferred upper limit thereof is 23.

[0027] As the above-mentioned amine compound having an amino equivalent of 30 or less, specifically, for example, hydrazine, carbohydrazide, oxalyl dihydrazide, and the like can be given. Among these, at least either one of hydrazine and carbohydrazide is preferred from the aspect that the effect of making the resulting sealant for liquid crystal display elements have excellent storage stability, adhesion, and low liquid crystal contamination property is more excellent.

[0028] As the epoxy compound that is a source of the adduct of the present application, for example, bisphenol A type epoxy compounds, bisphenol F type epoxy compounds, bisphenol E type epoxy compounds, bisphenol S type epoxy compounds, 2,2'-diallyl bisphenol 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, thioether type epoxy compounds, diphenyl ether type epoxy compounds, dicyclopentadiene type epoxy compounds, naphthalene type epoxy compounds, phenol novolak type epoxy compounds, o-cresol novolak type epoxy compounds, dicyclopentadiene novolak type epoxy compounds, biphenyl novolak type epoxy compounds, naphthalene phenol novolak type (Japanese: naphthalene phenol novolak type) epoxy compounds, glycidyl amine type epoxy compounds, alkyl polyhydric alcohol type epoxy compounds, rubber-modified type epoxy compounds, glycidyl ester compounds, and the like can be given. Among these, epoxy compounds having a structure from a compound having a phenolic hydroxyl group are preferable. As the above-mentioned epoxy compounds having a structure from a compound having a phenolic hydroxyl group, bisphenol A type epoxy compounds, bisphenol F type epoxy compounds, diphenyl ether type epoxy compounds are more preferable, and diphenyl ether type epoxy compounds are further preferable.

[0029] As the above-mentioned bisphenol A type epoxy compounds, for example, bisphenol A diglycidyl ether and the like can be given.

[0030] As the above-mentioned bisphenol F type epoxy compounds, for example, bisphenol F diglycidyl ether, bisphenol F type epoxy polymers, and the like can be given.

[0031] As the above-mentioned diphenyl ether type epoxy compounds, for example, bis(4-glycidyloxyphenyl) ether and the like can be given.

[0032] The preferable lower limit of the mass average molecular weight of the adduct of the present application is 200, and the preferable upper limit is 3000. By making the mass average molecular weight of the adduct of the present application 200 or more, the low liquid crystal contamination property of the obtained sealing agent for liquid crystal display elements becomes more excellent. By making the mass average molecular weight of the adduct of the present application 3000 or less, the handling property of the obtained sealing agent for liquid crystal display elements becomes more excellent. The more preferable lower limit of the mass average molecular weight of the adduct of the present application is 300, and the more preferable upper limit is 1500.

[0033] Note that, in the present specification, the above-mentioned mass average molecular weight is a value determined using gel permeation chromatography (GPC) using tetrahydrofuran as a solvent and converted to polystyrene. As the column at the time of determining the mass average molecular weight based on polystyrene conversion using GPC, for example, Shodex LF-804 (manufactured by Showa Denko K.K.) and the like can be given.

[0034] From the viewpoint of storage stability, the adduct of the present application is preferably in a solid state at 25°C.

[0035] The preferred lower limit of the melting point of the adduct of the present application is 60°C, and the more preferred lower limit is 90°C.

[0036] In addition, from the viewpoint of the curability and the like of the obtained sealing agent for liquid crystal display elements, the preferred upper limit of the melting point of the adduct of the present application is 180°C, and the more preferred upper limit is 150°C.

[0037] Note that the melting point can be determined by differential scanning calorimetry or a commercially available melting point measuring device.

[0038] The preferred lower limit of the content of the adduct of the present application with respect to 100 parts by mass of the curable resin described later is 3 parts by mass, and the preferred upper limit is 70 parts by mass. By making the content of the adduct of the present application with respect to 100 parts by mass of the curable resin be 3 parts by mass or more, the adhesiveness of the obtained sealing agent for liquid crystal display elements becomes more excellent. By making the content of the adduct of the present application with respect to 100 parts by mass of the curable resin be 70 parts by mass or less, the low liquid crystal contamination property and the storage stability of the obtained sealing agent for liquid crystal display elements become more excellent. The more preferred lower limit of the content of the adduct of the present application with respect to 100 parts by mass of the curable resin is 6 parts by mass, and the more preferred upper limit is 35 parts by mass.

[0039] In addition, in the case where the curable resin described above contains an epoxy compound described later, the preferred lower limit of the content of the adduct of the present application with respect to 1 equivalent of the epoxy compound is 0.5 equivalent, and the preferred upper limit is 2.0 equivalent. By making the content of the adduct of the present application with respect to 1 equivalent of the epoxy compound described above be 0.5 equivalent or more, the curability, the adhesiveness of the obtained sealing agent for liquid crystal display elements become more excellent. By making the content of the adduct of the present application with respect to 1 equivalent of the epoxy compound described above be 2.0 equivalent or less, the storage stability and the low liquid crystal contamination property of the obtained sealing agent for liquid crystal display elements become more excellent. The more preferred lower limit of the content of the adduct of the present application with respect to 1 equivalent of the epoxy compound described above is 0.8 equivalent, and the more preferred upper limit is 1.2 equivalent.

[0040] The sealing agent for liquid crystal display elements of the present application contains a curable resin.

[0041] The curable resin described above preferably contains an epoxy compound.

[0042] As the above-mentioned epoxy compounds, for example, bisphenol A type epoxy compounds, bisphenol F type epoxy compounds, bisphenol E type epoxy compounds, bisphenol S type epoxy compounds, 2, 2'-diallyl bisphenol A type epoxy compounds, hydrogenated bisphenol type epoxy compounds, propylene oxide addition bisphenol A type epoxy compounds, resorcinol type epoxy compounds, biphenyl type epoxy compounds, thioether type epoxy compounds, diphenyl ether type epoxy compounds, dicyclopentadiene type epoxy compounds, naphthalene type epoxy compounds, phenol formaldehyde type epoxy compounds, o-cresol formaldehyde type epoxy compounds, dicyclopentadiene formaldehyde type epoxy compounds, biphenol formaldehyde type epoxy compounds, naphthol formaldehyde type epoxy compounds, glycidyl amine type epoxy compounds, alkyl polyhydric alcohol type epoxy compounds, rubber-modified type epoxy compounds, glycidyl ester compounds, and the like can be given.

[0043] As the above-mentioned bisphenol A type epoxy compounds, for example, jER828EL, jER1004 (both manufactured by Mitsubishi Chemical Corporation), EPICLON 850 (manufactured by DIC Corporation), and the like can be given.

[0044] As the above-mentioned bisphenol F type epoxy compounds, for example, jER806, jER4004 (both manufactured by Mitsubishi Chemical Corporation), EPICLON EXA-830CRP (manufactured by DIC Corporation), and the like can be given.

[0045] As the above-mentioned bisphenol E type epoxy compounds, for example, EPOMIC R710 (manufactured by Mitsui Chemicals, Inc.), and the like can be given.

[0046] As the above-mentioned bisphenol S type epoxy compounds, for example, EPICLON EXA-1514 (manufactured by DIC Corporation), and the like can be given.

[0047] As the above-mentioned 2, 2'-diallyl bisphenol A type epoxy compounds, for example, RE-810NM (manufactured by Nippon Kayaku Co., Ltd.), and the like can be given.

[0048] As the above-mentioned hydrogenated bisphenol type epoxy compounds, for example, EPICLON EXA-7015 (manufactured by DIC Corporation), and the like can be given.

[0049] As the above-mentioned propylene oxide addition bisphenol A type epoxy compounds, for example, EP-4000S (manufactured by ADEKA Corporation), and the like can be given.

[0050] As the above-mentioned resorcinol type epoxy compounds, for example, EX-201 (manufactured by Nagase Chemtex Corporation), and the like can be given.

[0051] As the above-mentioned biphenyl type epoxy compounds, for example, jER YX-4000H (manufactured by Mitsubishi Chemical Corporation), and the like can be given.

[0052] As a commercially available product of the above-mentioned sulfide type epoxy compound, for example, YSLV-50TE (manufactured by NIPPON STEEL Chemical & Material Co., Ltd.) or the like can be given.

[0053] As a commercially available product of the above-mentioned diphenyl ether type epoxy compound, for example, YSLV-80DE (manufactured by NIPPON STEEL Chemical & Material Co., Ltd.) or the like can be given.

[0054] As a commercially available product of the above-mentioned dicyclopentadiene type epoxy compound, for example, EP-4088S (manufactured by ADEKA Corporation) or the like can be given.

[0055] As a commercially available product of the above-mentioned naphthalene type epoxy compound, for example, EPICLON HP-4032, EPICLON EXA-4700 (both manufactured by DIC Corporation) or the like can be given.

[0056] As a commercially available product of the above-mentioned phenol novolak type epoxy compound, for example, EPICLON N-770 (manufactured by DIC Corporation) or the like can be given.

[0057] As a commercially available product of the above-mentioned o-cresol novolak type epoxy compound, for example, EPICLON N-670-EXP-S (manufactured by DIC Corporation) or the like can be given.

[0058] As a commercially available product of the above-mentioned dicyclopentadiene novolak type epoxy compound, for example, EPICLON HP-7200 (manufactured by DIC Corporation) or the like can be given.

[0059] As a commercially available product of the above-mentioned diphenyl novolak type epoxy compound, for example, NC-3000P (manufactured by Nippon Kayaku Co., Ltd.) or the like can be given.

[0060] As a commercially available product of the above-mentioned naphthalene phenol novolak type epoxy compound, for example, ESN-165S (manufactured by NIPPON STEEL Chemical & Material Co., Ltd.) or the like can be given.

[0061] As a commercially available product of the above-mentioned glycidyl amine type epoxy compound, for example, jER630 (manufactured by Mitsubishi Chemical Corporation), EPICLON 430 (manufactured by DIC Corporation), TETRAD-X (manufactured by Mitsubishi Gas Chemical Company, Inc.) or the like can be given.

[0062] As the commercially available product of the above-mentioned alkyl polyol type epoxy compound, for example, ZX-1542 (manufactured by NIPPON STEEL Chemical & Material Co., Ltd.), EPICLON 726 (manufactured by DIC Corporation), EPOLIGHT 80MFA (manufactured by Kyoeisha Chemical Co., Ltd.), Denacol EX-611 (manufactured by Nagase Chemtex Corporation), and the like can be given.

[0063] As the commercially available product of the above-mentioned rubber-modified type epoxy compound, for example, YR-450, YR-207 (both manufactured by NIPPON STEEL Chemical & Material Co., Ltd.), Epolead PB (manufactured by Daicel Corporation), and the like can be given.

[0064] As the commercially available product of the above-mentioned glycidyl ester compound, for example, Denacol EX-147 (manufactured by Nagase Chemtex Corporation), and the like can be given.

[0065] As the other commercially available product of the above-mentioned epoxy compound, for example, YDC-1312, YSLV-80XY, YSLV-90CR (all manufactured by NIPPON STEEL Chemical & Material Co., Ltd.), XAC4151 (manufactured by Asahi Kasei Corporation), jER1031, jER1032 (both manufactured by Mitsubishi Chemical Corporation), EXA-7120 (manufactured by DIC Corporation), TEPIC (manufactured by Nissan Chemical Corporation), and the like can be given.

[0066] As the above-mentioned epoxy compound, a partially (meth)acrylic acid-modified epoxy compound is also suitably used.

[0067] Note that, in the present specification, the above-mentioned partially (meth)acrylic acid-modified epoxy compound refers to a compound having one or more than one epoxy group and (meth)acryloyl group in one molecule, which can be obtained by reacting a part of the epoxy groups of an epoxy compound having two or more epoxy groups with (meth)acrylic acid.

[0068] Note that, in the present specification, the above-mentioned "(meth)acrylic acid" refers to acrylic acid or methacrylic acid, and the above-mentioned "(meth)acryloyl group" refers to acryloyl group or methacryloyl group.

[0069] As the commercially available product of the above-mentioned partially (meth)acrylic acid-modified epoxy compound, for example, UVACURE 1561, KRM8030, KRM8287 (all manufactured by DAICEL-ALLNEX Corporation), and the like can be given.

[0070] In addition, the above-mentioned curable resin can contain a (meth)acrylic acid-based compound.

[0071] As the above (meth) acrylic compound, for example, (meth) acrylate compounds, epoxy (meth) acrylate, urethane (meth) acrylate, and the like can be given. Among them, epoxy (meth) acrylate is preferred. In addition, from the viewpoint of reactivity, the above (meth) acrylic compound preferably has two or more (meth) acryloyl groups in one molecule.

[0072] Note that in the present specification, the above "(meth) acrylic compound" means a compound having a (meth) acryloyl group. In addition, the above "(meth) acrylate" means acrylate or methacrylate, and the above "epoxy (meth) acrylate" means a compound obtained by reacting all of the epoxy groups in an epoxy compound with (meth) acrylic acid.

[0073] As the monofunctional compound in the above (meth) acrylate compound, for example, 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, isomyristyl (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, dicyclopentenyl (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, phenoxy polyethylene glycol (meth) acrylate, tetrahydrofurfuryl (meth) acrylate, ethyl carbitol (meth) acrylate, 2,2,2-trifluoroethyl (meth) acrylate, 2,2,3,3-tetrafluoropropyl (meth) acrylate, 1H, 1H, 5H-octafluoropentyl (meth) acrylate, imide (meth) acrylate, dimethylaminoethyl (meth) acrylate, diethylaminoethyl (meth) acrylate, succinic acid-2- (meth) acryloyloxyethyl ester, hexahydrophthalic acid-2- (meth) acryloyloxyethyl ester, 2- (meth) acryloyloxyethyl 2-hydroxypropyl phthalate, 2- (meth) acryloyloxyethyl phosphate, glycidyl (meth) acrylate, and the like can be given.

[0074] In addition, as the 2-functional compound among the above-mentioned (meth)acrylate compounds, for example, 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, polypropylene glycol di(meth)acrylate, neopentyl glycol di(meth)acrylate, oxirane-addition bisphenol A di(meth)acrylate, oxirane-addition bisphenol A di(meth)acrylate, oxirane-addition bisphenol F di(meth)acrylate, dihydroxymethyl dicyclopentadienyl di(meth)acrylate, oxirane-modified isocyanuric acid di(meth)acrylate, 2-hydroxy-3-(meth)acryloyloxypropyl (meth)acrylate, carbonate glycol di(meth)acrylate, polyether glycol di(meth)acrylate, polyester glycol di(meth)acrylate, polycaprolactone glycol di(meth)acrylate, polybutadiene glycol di(meth)acrylate, and the like can be mentioned.

[0075] In addition, as the 3 or more functional compound among the above-mentioned (meth)acrylate compounds, for example, trimethylolpropane tri(meth)acrylate, oxirane-addition trimethylolpropane tri(meth)acrylate, oxirane-addition trimethylolpropane tri(meth)acrylate, caprolactone-modified trimethylolpropane tri(meth)acrylate, oxirane-addition isocyanuric acid tri(meth)acrylate, glycerol tri(meth)acrylate, oxirane-addition glycerol tri(meth)acrylate, pentaerythritol tri(meth)acrylate, tris(meth)acryloyloxyethyl phosphate, ditrimethylolpropane tetra(meth)acrylate, pentaerythritol tetra(meth)acrylate, dipentaerythritol penta(meth)acrylate, dipentaerythritol hexa(meth)acrylate, and the like can be mentioned.

[0076] As the above-mentioned epoxy (meth)acrylate, for example, an epoxy (meth)acrylate obtained by reacting an epoxy compound with (meth)acrylic acid in the presence of an alkaline catalyst according to a conventional method, and the like can be mentioned.

[0077] As the epoxy compound to be used as a raw material for synthesizing the above-mentioned epoxy (meth)acrylate, the same epoxy compound as the above-mentioned epoxy compound contained in the curable resin of the sealing agent for liquid crystal display elements of the present application can be used.

[0078] As the commercially available product of the above-mentioned epoxy (meth) acrylate, for example, DAICEL-ALLNEX Co., Ltd.'s epoxy (meth) acrylate, Shin-Nakamura Chemical Co., Ltd.'s epoxy (meth) acrylate, Kyoeisha Chemical Co., Ltd.'s epoxy (meth) acrylate, Nagase Chemtex Co., Ltd.'s epoxy (meth) acrylate, and the like can be mentioned.

[0079] As the DAICEL-ALLNEX Co., Ltd.'s epoxy (meth) acrylate mentioned above, for example, EBECRYL 860, EBECRYL 3200, EBECRYL 3201, EBECRYL 3412, EBECRYL 3600, EBECRYL 3700, EBECRYL 3701, EBECRYL 3702, EBECRYL 3703, EBECRYL 3708, EBECRYL 3800, EBECRYL 6040, EBECRYL RDX63182, and the like can be mentioned.

[0080] As the Shin-Nakamura Chemical Co., Ltd.'s epoxy (meth) acrylate mentioned above, for example, EA-1010, EA-1020, EA-5323, EA-5520, EA-CHD, EMA-1020, and the like can be mentioned.

[0081] As the Kyoeisha Chemical Co., Ltd.'s epoxy (meth) acrylate mentioned above, for example, 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, and the like can be mentioned.

[0082] As the Nagase Chemtex Co., Ltd.'s epoxy (meth) acrylate mentioned above, for example, Denacol Acrylate DA-141, Denacol Acrylate DA-314, Denacol Acrylate DA-911, and the like can be mentioned.

[0083] The urethane (meth) acrylate mentioned above can be obtained, for example, by reacting a (meth) acrylate derivative having a hydroxyl group with an isocyanate compound in the presence of a catalytic amount of a tin-based compound.

[0084] As the isocyanate compound which is a raw material of the above urethane (meth)acrylate, for example, isophorone diisocyanate, 2,4-toluene diisocyanate, 2,6-toluene diisocyanate, hexamethylene diisocyanate, trimethylhexamethylene diisocyanate, diphenylmethane-4,4'-diisocyanate (MDI), hydrogenated MDI, polymeric MDI, 1,5-naphthalene diisocyanate, norbornane diisocyanate, dimethyl diphenyl diisocyanate, xylylene diisocyanate (XDI), hydrogenated XDI, lysine diisocyanate, triphenylmethane triisocyanate, tris(isocyanate phenyl) thiophosphate, tetramethyl xylylene diisocyanate, 1,6,11-undecane triisocyanate, and the like can be given.

[0085] In addition, as the isocyanate compound which is a raw material of the above urethane (meth)acrylate, a chain-extended isocyanate compound obtained by the reaction of a polyol with an excess of an isocyanate compound can also be used.

[0086] As the above polyol, for example, ethylene glycol, propylene glycol, glycerol, sorbitol, trimethylolpropane, carbonate diol, polyether diol, polyester diol, polycaprolactone diol, and the like can be given.

[0087] As the above (meth)acrylic acid derivative having a hydroxyl group, for example, a mono(meth)acrylic acid hydroxyalkyl ester, a dihydric alcohol mono(meth)acrylate, a trihydric alcohol mono(meth)acrylate or di(meth)acrylate, an epoxy (meth)acrylate, and the like can be given.

[0088] As the above mono(meth)acrylic acid hydroxyalkyl ester, for example, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, and the like can be given.

[0089] As the above dihydric alcohol, for example, ethylene glycol, propylene glycol, 1,3-propanediol, 1,3-butanediol, 1,4-butanediol, polyethylene glycol, and the like can be given.

[0090] As the above trihydric alcohol, for example, trimethylolethane, trimethylolpropane, glycerol, and the like can be given.

[0091] As the above epoxy (meth)acrylate, for example, a bisphenol A type epoxy (meth)acrylate, and the like can be given.

[0092] As commercially available products of the above urethane (meth)acrylates, for example, there can be mentioned urethane (meth)acrylates manufactured by DAIICHI KOGYO Co., Ltd., urethane (meth)acrylates manufactured by DAICEL-ALLNEX Co., Ltd., urethane (meth)acrylates manufactured by KANEKA CORPORATION, urethane (meth)acrylates manufactured by SHIN-NIKKAKO CHEMICAL CO., LTD., and the like.

[0093] As the above urethane (meth)acrylates manufactured by DAIICHI KOGYO Co., Ltd., for example, there can be mentioned M-1100, M-1200, M-1210, M-1600, and the like.

[0094] As the above urethane (meth)acrylates manufactured by DAICEL-ALLNEX Co., Ltd., for example, there can be mentioned EBECRYL 210, EBECRYL 220, EBECRYL 230, EBECRYL 270, EBECRYL 1290, EBECRYL 2220, EBECRYL 4827, EBECRYL 4842, EBECRYL 4858, EBECRYL 5129, EBECRYL 6700, EBECRYL 8402, EBECRYL 8803, EBECRYL 8804, EBECRYL 8807, EBECRYL 9260, and the like.

[0095] As the above urethane (meth)acrylates manufactured by DAIICHI KOGYO Co., Ltd., for example, there can be mentioned M-1100, M-1200, M-1210, M-1600, and the like.

[0096] As the above urethane (meth)acrylates manufactured by KANEKA CORPORATION, for example, there can be mentioned 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, and the like.

[0097] As the urethane (meth) acrylate prepared by the above-mentioned Kyoeisha Chemical Co., Ltd., for example, AH-600, AI-600, AT-600, UA-101I, UA-101T, UA-306H, UA-306I, UA-306T, and the like can be given.

[0098] As the curable resin, in the case where the above-mentioned (meth) acryl compound is contained in addition to the above-mentioned epoxy compound, or in the case where the above-mentioned partial (meth) acryl-modified epoxy compound is contained, it is preferable that the ratio of the (meth) acryl group in the total of the epoxy group and the (meth) acryl group in the above-mentioned curable resin be 30 mol% or more and 95 mol% or less. By making the ratio of the above-mentioned (meth) acryl group be within this range, the occurrence of liquid crystal contamination is suppressed, and the adhesiveness of the obtained sealing agent for liquid crystal display elements becomes more excellent.

[0099] From the viewpoint of further suppressing the occurrence of liquid crystal contamination, the above-mentioned curable resin preferably has a hydrogen bonding unit such as an -OH group, an -NH- group, an -NH2 group, or the like.

[0100] The sealing agent for liquid crystal display elements of the present application preferably contains a photoradical polymerization initiator.

[0101] As the above-mentioned photoradical polymerization initiator, for example, a benzophenone compound, an acetophenone compound, an acyloxyphosphine compound, a titanocene compound, an oxime ester compound, a benzoin ether compound, a thioxanthone compound, or the like can be given.

[0102] As the above-mentioned photoradical polymerization initiator, specifically, for example, 1-hydroxycyclohexyl phenyl 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-diphenylethan-1-one, bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide, 2-methyl-1-(4-methylthiophenyl)-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-benzoyl oxime), 2,4,6-trimethylbenzoyldiphenylphosphine oxide, and the like can be given.

[0103] The above-mentioned photoradical polymerization initiator can be used alone, or two or more kinds can be used in combination.

[0104] The content of the above-mentioned photoradical polymerization initiator is preferably 0.5 parts by mass or more and 10 parts by mass or less relative to 100 parts by mass of the above-mentioned curable resin. By setting the content of the above-mentioned photoradical polymerization initiator within this range, the resulting sealing material for liquid crystal display elements inhibits liquid crystal contamination and has more excellent storage stability and photocurability. The content of the above-mentioned photoradical polymerization initiator is more preferably 1 part by mass or more and 7 parts by mass or less.

[0105] The sealing material for liquid crystal display elements of the present application can contain a thermal radical polymerization initiator.

[0106] As the above-mentioned thermal radical polymerization initiator, for example, a thermal radical polymerization initiator composed of an azo compound, an organic peroxide, or the like can be given. Among them, from the viewpoint of inhibiting liquid crystal contamination, an initiator composed of an azo compound (hereinafter, also referred to as "azo initiator") is preferred, and an initiator composed of a high-molecular azo compound (hereinafter, also referred to as "high-molecular azo initiator") is more preferred.

[0107] The above-mentioned thermal radical polymerization initiator can be used alone or in combination with two or more kinds.

[0108] Note that, in the present specification, the above-mentioned "high-molecular azo compound" refers to a compound having an azo group, generating a radical capable of reacting with a (meth)acryl group by heat, and having a number average molecular weight of 300 or more.

[0109] The above-mentioned high-molecular azo compound preferably has a number average molecular weight of 1,000 or more and 300,000 or less. By setting the number average molecular weight of the above-mentioned high-molecular azo compound within this range, adverse effects on liquid crystals can be prevented, and the high-molecular azo compound can be easily mixed into the curable resin. The number average molecular weight of the above-mentioned high-molecular azo compound is more preferably 5,000 or more and 1,000,000 or less, further preferably 10,000 or more and 900,000 or less.

[0110] Note that, in the present specification, the above-mentioned number average molecular weight is a value determined using gel permeation chromatography (GPC) with tetrahydrofuran as a solvent and converted to polystyrene. As a column for determining the number average molecular weight based on polystyrene conversion using GPC, for example, Shodex LF-804 (manufactured by Showa Denko K.K.) or the like can be given.

[0111] As the above-mentioned high-molecular azo compound, for example, a high-molecular azo compound having a structure in which a plurality of polyalkylene oxide, polydimethylsiloxane, or the like units are linked via an azo group can be given.

[0112] As the above-mentioned high molecular azo compound having a structure in which a plurality of polyalkylene oxide or the like units are linked via an azo group, a high molecular azo compound having a polyethylene oxide structure is preferable.

[0113] As the above-mentioned high molecular azo compound, specifically, for example, a polycondensate of 4,4'-azobis(4-cyanopentanoic acid) and a polyalkylene glycol, a polycondensate of 4,4'-azobis(4-cyanopentanoic acid) and a polydimethylsiloxane having a terminal amino group, or the like can be mentioned.

[0114] As the above-mentioned commercially available product in the high molecular azo initiator, for example, VPE-0201, VPE-0401, VPE-0601, VPS-0501, VPS-1001 (all of which are manufactured by FUJIFILM and LIGHTNING BATTERY Co., Ltd.), or the like can be mentioned.

[0115] In addition, as the azo initiator which is not a high molecule, for example, V-65, V-501 (both of which are manufactured by FUJIFILM and LIGHTNING BATTERY Co., Ltd.), or the like can be mentioned.

[0116] As the above-mentioned organic peroxide, for example, a ketone peroxide, a ketal peroxide, a hydrogen peroxide, a dialkyl peroxide, an ester peroxide, a diacyl peroxide, a peroxydicarbonate, or the like can be mentioned.

[0117] The content of the above-mentioned thermal radical polymerization initiator is preferably 0.1 parts by mass or more and 10 parts by mass or less relative to 100 parts by mass of the above-mentioned curable resin. By setting the content of the above-mentioned thermal radical polymerization initiator within this range, the obtained sealing material for liquid crystal display elements is inhibited from being contaminated with liquid crystals, and the storage stability, thermal curability, and the like become more excellent. The content of the above-mentioned thermal radical polymerization initiator is more preferably 0.3 parts by mass or more and 5 parts by mass or less.

[0118] The sealing material for liquid crystal display elements of the present application can contain a filler for the purpose of increasing the viscosity, improving the adhesiveness based on the stress dispersion effect, improving the linear expansion coefficient, increasing the moisture resistance of the cured product, and the like.

[0119] As the above-mentioned filler, an inorganic filler, an organic filler, or the like can be used.

[0120] As the above-mentioned inorganic filler, for example, silica, talc, glass beads, asbestos, gypsum, diatomite, green earth, 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, or the like can be mentioned.

[0121] As the above-mentioned organic filler, for example, polyester microparticles, polyurethane microparticles, vinyl polymer microparticles, acrylic polymer microparticles, or the like can be mentioned.

[0122] The above-mentioned filler can be used alone or in combination with two or more kinds.

[0123] The content of the above-mentioned filler in 100 parts by mass of the sealing agent for liquid crystal display elements according to the present application is preferably 10 parts by mass or more and 70 parts by mass or less. By setting the content of the above-mentioned filler within this range, the effect of improving the adhesion without deteriorating the coatability and the like becomes more excellent. The content of the above-mentioned filler is more preferably 20 parts by mass or more and 60 parts by mass or less.

[0124] The sealing agent for liquid crystal display elements according to the present application can contain a silane coupling agent. The above-mentioned silane coupling agent mainly functions as an adhesion aid for good adhesion of the sealing agent for liquid crystal display elements to a substrate and the like.

[0125] As the above-mentioned silane coupling agent, for example, 3-aminopropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-isocyanatepropyltriethoxysilane and the like are suitably used. They are excellent in the effect of improving the adhesion to a substrate and the like, and can suppress the outflow of the curable resin into a liquid crystal by chemical bonding with the curable resin. Among them, 3-glycidoxypropyltrimethoxysilane is preferred.

[0126] The above-mentioned silane coupling agent can be used alone or in combination with two or more kinds.

[0127] The content of the above-mentioned silane coupling agent in 100 parts by mass of the sealing agent for liquid crystal display elements according to the present application is preferably 0.1 parts by mass or more and 10 parts by mass or less. By setting the content of the above-mentioned silane coupling agent within this range, the occurrence of liquid crystal contamination is suppressed, and the effect of improving the adhesion becomes more excellent. The content of the above-mentioned silane coupling agent is more preferably 0.3 parts by mass or more and 5 parts by mass or less.

[0128] The sealing agent for liquid crystal display elements according to the present application can contain a light shielding agent. By containing the above-mentioned light shielding agent, the sealing agent for liquid crystal display elements according to the present application can be suitably used as a light shielding sealing agent.

[0129] As the above-mentioned light shielding agent, for example, iron oxide, titanium black, aniline black, cyanine black, fullerene, carbon black, resin-coated carbon black and the like can be mentioned. Among them, titanium black is preferred.

[0130] The above titanium black is a substance in which the transmittance for light in the vicinity of the ultraviolet region, particularly light having a wavelength of 370 nm or more and 450 nm or less, is high compared to the average transmittance for light having a wavelength of 300 nm or more and 800 nm or less. That is, the above titanium black is an opacifier having the property of imparting opaqueness to the sealing material for liquid crystal display elements of the present application by sufficiently shielding light having a wavelength in the visible light region, and on the other hand, transmitting light having a wavelength in the vicinity of the ultraviolet region. Therefore, as the above photoradical polymerization initiator, by using a photoradical polymerization initiator capable of initiating a reaction using light having a wavelength in which the transmittance of the above titanium black is high, it is possible to further increase the photocurability of the sealing material for liquid crystal display elements of the present application. On the other hand, as the opacifier contained in the sealing material for liquid crystal display elements of the present application, a substance having high insulation is preferred, and as the opacifier having high insulation, a titanium black is also suitable.

[0131] The optical density (OD value) per 1 μm of the above titanium black is preferably 3 or more, and more preferably 4 or more. The higher the opaqueness of the above titanium black, the better, and there is no particular upper limit to the OD value of the above titanium black, and it is usually 5 or less.

[0132] The above titanium black exerts a sufficient effect even without surface treatment, but a titanium black treated with an organic component such as a coupling agent, a titanium black coated with an inorganic component such as silicon oxide, titanium oxide, germanium oxide, aluminum oxide, zirconium oxide, magnesium oxide, and the like, and a surface-treated titanium black can also be used. Among these, a titanium black treated with an organic component is preferred from the aspect of further improving insulation.

[0133] In addition, a liquid crystal display element manufactured using the sealing material for liquid crystal display elements of the present application in which the above titanium black is compounded as an opacifier has sufficient opaqueness, and thus a liquid crystal display element having high contrast without light leakage and having excellent image display quality can be realized.

[0134] As the above commercially available titanium black, for example, a titanium black manufactured by Mitsubishi Materials Co., Ltd., a titanium black manufactured by Akahoshi Kasei Co., Ltd., and the like can be given.

[0135] As the above titanium black manufactured by Mitsubishi Materials Co., Ltd., for example, 12S, 13M, 13M-C, 13R-N, 14M-C, and the like can be given.

[0136] As the above titanium black manufactured by Akahoshi Kasei Co., Ltd., for example, Tilack D and the like can be given.

[0137] The preferred lower limit of the specific surface area of the above titanium black is 13 m 2 / g, and the preferred upper limit is 30 m 2 / g, and the more preferred lower limit is 15 m 2 / g, and a more preferable upper limit is 25 m 2 / g.

[0138] In addition, the preferable lower limit of the volume resistance of the above-mentioned titanium black is 0.5 Ω-cm, and the preferable upper limit is 3 Ω-cm, the more preferable lower limit is 1 Ω-cm, and the more preferable upper limit is 2.5 Ω-cm.

[0139] The primary particle diameter of the above-mentioned light shielding agent is not particularly limited as long as it is equal to or less than the distance between the substrates of the liquid crystal display element, and the preferable lower limit is 1 nm, and the preferable upper limit is 5000 nm. By making the primary particle diameter of the above-mentioned light shielding agent within this range, the light shielding property can be more excellent without deteriorating the coatability or the like of the obtained sealing agent for a liquid crystal display element. The more preferable lower limit of the primary particle diameter of the above-mentioned light shielding agent is 5 nm, the more preferable upper limit is 200 nm, the further preferable lower limit is 10 nm, and the further preferable upper limit is 100 nm.

[0140] Note that the primary particle diameter of the above-mentioned light shielding agent can be measured using NICOMP 380ZLS (PARTICLE SIZING SYSTEMS Co., Ltd.) by dispersing the above-mentioned light shielding agent in a solvent (water, an organic solvent, or the like).

[0141] The preferable lower limit of the content of the above-mentioned light shielding agent in 100 parts by mass of the sealing agent for a liquid crystal display element of the present application is 5 parts by mass, and the preferable upper limit is 80 parts by mass. By making the content of the above-mentioned light shielding agent within this range, the adhesion, the strength after curing, and the drawability of the obtained sealing agent for a liquid crystal display element are not greatly reduced, and more excellent light shielding property can be exerted. The more preferable lower limit of the content of the above-mentioned light shielding agent is 10 parts by mass, the more preferable upper limit is 70 parts by mass, the further preferable lower limit is 30 parts by mass, and the further preferable upper limit is 60 parts by mass.

[0142] The sealing agent for a liquid crystal display element of the present application can further contain, as needed, a stress relaxing agent, a reactive diluent, a thixotropic agent, a spacer, a curing accelerator, an antifoaming agent, a leveling agent, a polymerization inhibitor, or the like.

[0143] As a method of producing the sealing agent for a liquid crystal display element of the present application, for example, a method of mixing a curable resin, a thermal curing agent, and a photoradical polymerization initiator or the like added as needed using a mixer or the like can be mentioned.

[0144] As the above-mentioned mixer, for example, a homogenizing disperser, a homogenizing mixer, a universal mixer, a planetary mixer, a kneader, a three-roll mill, or the like can be mentioned.

[0145] By incorporating the electrically conductive fine particles in the sealing agent for a liquid crystal display element of the present application, a top-and-bottom conductive material can be produced.

[0146] As the above-mentioned conductive fine particles, for example, metal spheres, conductive fine particles in which a conductive metal layer is formed on the surface of a resin fine particle, and the like can be used. Among them, the conductive fine particles in which a conductive metal layer is formed on the surface of a resin fine particle are suitable because they can be conductively connected without damaging a transparent substrate or the like by virtue of the excellent elasticity of the resin fine particle.

[0147] A liquid crystal display element having a cured product of the sealing agent for a liquid crystal display element of the present application is also one of the present application.

[0148] As the liquid crystal display element of the present application, a liquid crystal display element of a narrow frame design is preferred. Specifically, the width of the frame portion around the liquid crystal display portion is preferably 2 mm or less.

[0149] Further, the coating width of the sealing agent for a liquid crystal display element of the present application at the time of manufacturing the liquid crystal display element of the present application is preferably 1 mm or less.

[0150] The sealing agent for a liquid crystal display element of the present application can be suitably used for the manufacturing of a liquid crystal display element based on a liquid crystal dropping process.

[0151] As a method of manufacturing the liquid crystal display element of the present application by a liquid crystal dropping process, for example, the following method or the like can be mentioned.

[0152] First, a process of forming a frame-shaped sealing pattern of the sealing agent for a liquid crystal display element of the present application on a substrate by screen printing, dispenser coating, or the like is performed. Next, a process of dropping and coating a fine drop of liquid crystal on the entire surface within the frame of the sealing pattern in a state where the sealing agent for a liquid crystal display element of the present application is not cured, and immediately overlapping another substrate is performed. Then, by a method of performing a process of heating and curing the sealing agent, a liquid crystal display element can be obtained. Further, a process of pre-curing the sealing agent by irradiating light such as ultraviolet rays to the sealing pattern portion can be performed before the process of heating and curing the sealing agent.

[0153] Effects of the Invention

[0154] According to the present application, a sealing agent for a liquid crystal display element which is excellent in storage stability, adhesiveness, and low liquid crystal contamination can be provided. Further, according to the present application, a liquid crystal display element using the sealing agent for a liquid crystal display element can be provided. DETAILED DESCRIPTION

[0155] Hereinafter, the present application will be described in more detail by citing examples, but the present application is not limited only to these examples.

[0156] (Synthesis of Adduct A)

[0157] In a 100 mL capacity round flask equipped with a reflux condenser, 50 mL of tetrahydrofuran, 50 mL of ethanol, 10 g (0.2 mole) of hydrazine monohydrate and 6.24 g (0.02 mole) of bisphenol F diglycidyl ether were added, and stirred at 60°C for one night while performing reflux cooling. Next, the resulting solution was transferred to a 1000 mL capacity round flask, 500 mL of water was added and stirred. Then, the resulting mixture was filtered, and the residue was vacuum dried in a vacuum oven at 60°C to obtain an adduct A in the form of a solid at 25°C. The mass average molecular weight of the adduct A was 1200.

[0158] The adduct A was confirmed to be an adduct having a structure from hydrazine and a structure from bisphenol F diglycidyl ether by 1 H-NMR, 13 C-NMR and FT-IR.

[0159] (Synthesis of Adduct B)

[0160] Instead of 6.24 g (0.02 mole) of bisphenol F diglycidyl ether, 38.4 g (0.02 mole) of bisphenol F type epoxy polymer was used, and otherwise, the same operation as described above in "(Synthesis of Adduct A)" was performed to obtain an adduct B in the form of a solid at 25°C. The mass average molecular weight of the adduct B was 1950.

[0161] The adduct B was confirmed to be an adduct having a structure from hydrazine and a structure from bisphenol F type epoxy polymer by 1 H-NMR, 13 C-NMR and FT-IR.

[0162] (Synthesis of Adduct C)

[0163] Instead of 6.24 g (0.02 mole) of bisphenol F diglycidyl ether, 6.8 g (0.02 mole) of bisphenol A diglycidyl ether was used, and otherwise, the same operation as described above in "(Synthesis of Adduct A)" was performed to obtain an adduct C in the form of a solid at 25°C. The mass average molecular weight of the adduct C was 1250.

[0164] The adduct C was confirmed to be an adduct having a structure from hydrazine and a structure from bisphenol A diglycidyl ether by 1 H-NMR, 13 C-NMR and FT-IR.

[0165] (Synthesis of Adduct D)

[0166] Instead of bisphenol F diglycidyl ether 6.24 g (0.02 mole), bis(4-glycidyloxyphenyl) ether 6.28 g (0.02 mole) was used, and otherwise the same operation as described above in "(Synthesis of Adduct A)" was performed to obtain Adduct D as a solid at 25°C. The mass average molecular weight of Adduct D was 1200.

[0167] By 1 H-NMR, 13 C-NMR and FT-IR, it was confirmed that Adduct D was an adduct having a structure from hydrazine and a structure from bis(4-glycidyloxyphenyl) ether.

[0168] (Synthesis of Adduct E)

[0169] Instead of bisphenol F diglycidyl ether 6.24 g (0.02 mole), phenol novolak epoxy compound 11.4 g (0.02 mole) was used, and otherwise the same operation as described above in "(Synthesis of Adduct A)" was performed to obtain Adduct E as a solid at 25°C. The mass average molecular weight of Adduct E was 2300.

[0170] By 1 H-NMR, 13 C-NMR and FT-IR, it was confirmed that Adduct E was an adduct having a structure from hydrazine and a structure from phenol novolak epoxy compound.

[0171] (Synthesis of Adduct F)

[0172] In a 200 mL capacity flask equipped with a reflux condenser, tetrahydrofuran 50 mL, water 50 mL, carbodihydrazide 18 g (0.2 mole) and bisphenol F diglycidyl ether 6.24 g (0.02 mole) were added, and stirred at 60°C for one night while performing reflux cooling. Next, the resulting solution was transferred to a 1000 mL capacity flask, and water 500 mL was added to perform stirring. Then, the resulting mixture was filtered, and the residue was vacuum dried at 60°C in a vacuum oven to obtain Adduct F as a solid at 25°C. The mass average molecular weight of Adduct F was 1350.

[0173] By 1 H-NMR, 13 C-NMR and FT-IR, it was confirmed that Adduct F was an adduct having a structure from carbodihydrazide and a structure from bisphenol F diglycidyl ether.

[0174] (Synthesis of Adduct G)

[0175] Using 38.4 g (0.02 mole) of bisphenol F type epoxy polymer instead of 6.24 g (0.02 mole) of bisphenol F diglycidyl ether, and otherwise in the same manner as described above in "(Synthesis of Adduct F)", an adduct G was obtained as a solid at 25°C. The mass average molecular weight of the adduct G was 2100.

[0176] By 1 H-NMR, 13 C-NMR and FT-IR, the adduct G was confirmed to be an adduct having a structure from the carbodihydrazide and a structure from the bisphenol F type epoxy polymer.

[0177] (Synthesis of Adduct H)

[0178] Using 6.8 g (0.02 mole) of bisphenol A diglycidyl ether instead of 6.24 g (0.02 mole) of bisphenol F diglycidyl ether, and otherwise in the same manner as described above in "(Synthesis of Adduct F)", an adduct H was obtained as a solid at 25°C. The mass average molecular weight of the adduct H was 1400.

[0179] By 1 H-NMR, 13 C-NMR and FT-IR, the adduct H was confirmed to be an adduct having a structure from the carbodihydrazide and a structure from the bisphenol A diglycidyl ether.

[0180] (Synthesis of Adduct I)

[0181] Using 6.28 g (0.02 mole) of bis(4-glycidyloxyphenyl) ether instead of 6.24 g (0.02 mole) of bisphenol F diglycidyl ether, and otherwise in the same manner as described above in "(Synthesis of Adduct F)", an adduct I was obtained as a solid at 25°C. The mass average molecular weight of the adduct I was 1350.

[0182] By 1 H-NMR, 13 C-NMR and FT-IR, the adduct I was confirmed to be an adduct having a structure from the carbodihydrazide and a structure from the bis(4-glycidyloxyphenyl) ether.

[0183] (Synthesis of Adduct J)

[0184] Using 11.4 g (0.02 mole) of phenol novolak type epoxy compound instead of 6.24 g (0.02 mole) of bisphenol F diglycidyl ether, and otherwise in the same manner as described above in "(Synthesis of Adduct F)", an adduct J was obtained as a solid at 25°C. The mass average molecular weight of the adduct J was 2500.

[0185] By1 H-NMR, 13 C-NMR and FT-IR confirmed that adduct J is an adduct with structures derived from carbodihydrazide and phenolic aldehyde type epoxy compounds.

[0186] (Examples 1-10, Comparative Examples 1-4)

[0187] According to the mixing ratios recorded in Tables 1 and 2, the materials were mixed using a planetary mixer (THINKY Corporation, "Defoaming Rentarō"), and then further mixed using a three-roll mill, thereby preparing the sealants for liquid crystal display elements of Examples 1 to 10 and Comparative Examples 1 to 4.

[0188] <Evaluation>

[0189] The sealants used to obtain the liquid crystal display elements in the examples and comparative examples were evaluated as follows. The results are shown in Tables 1 and 2.

[0190] (Maintain stability)

[0191] For the sealants used in the liquid crystal display elements obtained in the examples and comparative examples, the initial viscosity immediately after manufacturing and the viscosity after storage at 25°C for one week were measured. The viscosity increase rate was defined as (viscosity after storage) / (initial viscosity). A viscosity increase rate less than 2.0 was marked with "◎", a viscosity increase rate of 2.0 or more but less than 3.0 was marked with "○", and a viscosity increase rate of 3.0 or more was marked with "×". The storage stability was evaluated.

[0192] It should be noted that the viscosity of the sealant for liquid crystal display elements was measured using an E-type viscometer (manufactured by BROOK FIELD, "DV-III") at 25°C and a rotation speed of 1.0 rpm.

[0193] (Adhesion)

[0194] One part by mass of spacer particles was dispersed in 100 parts by mass of the sealant for each liquid crystal display element obtained in the Examples and Comparative Examples. Micropearl SI-H050 (manufactured by Sekisui Chemicals Co., Ltd.) was used as the spacer particles. Next, the liquid crystal display element sealant with dispersed spacer particles was dropped onto one of two glass substrates (4.5 mm in length and 2.5 mm in width) with an ITO film. The other glass substrate with an ITO film was then attached to it in a cross shape, and irradiated with a metal halide lamp at 3000 mJ / cm². 2 After exposure to ultraviolet light, the substrate was heated at 120°C for 60 minutes to obtain an adhesiveness test piece. The strength at which panel peeling occurred was measured by pressing a metal cylinder with a radius of 5 mm into the end of the substrate in the prepared adhesiveness test piece at a speed of 5 mm / min.

[0195] The case where the value obtained by dividing the obtained measurement value (kgf) by the sealing diameter (cm) is 3.0 kgf / cm or greater is denoted by "O", the case where the value is greater than 2.0 kgf / cm and less than 3.0 kgf / cm is denoted by "D", and the case where the value is 2.0 kgf / cm or less is denoted by "X", and the adhesiveness is evaluated.

[0196] In addition, the adhesiveness was similarly evaluated using a glass substrate with a TN polyimide alignment film (Dow Corning Toray Co., Ltd., "SE6414") instead of the glass substrate with the ITO thin film.

[0197] (Low liquid crystal contamination)

[0198] In the examples and comparative examples, 1 part by mass of spacer fine particles (Dow Corning Toray Co., Ltd., "Micropearl SI-H050") having an average particle diameter of 7 μm was dispersed in 100 parts by mass of the sealing agent for liquid crystal display elements 100, and the dispersion was degassed using a centrifugal degassing machine (Awatron AW-1). The degassed sealing agent for liquid crystal display elements was coated in a frame shape on one of two substrates with alignment films and ITO thin films using a dispenser under the conditions of a nozzle diameter of 0.4 mmφ, a nozzle gap of 42 μm, an injection pressure of the syringe of 100 to 400 kPa, and a coating speed of 60 mm / sec. At this time, the injection pressure was adjusted so that the line width of the sealing agent for liquid crystal display elements became about 1.0 mm. Next, a fine droplet of liquid crystal (Tokyo Chemical Industry Co., Ltd., "4-pentyl-4-cyanobiphenyl") was dropped and coated on the entire surface of the frame of the sealing agent for liquid crystal display elements of the substrate on which the sealing agent for liquid crystal display elements was coated, and after standing for 2 hours, the other substrate was attached under vacuum. For the attached substrate, after standing for 15 minutes after attachment, the sealing agent for liquid crystal display elements was pre-cured by irradiating the portion of the sealing agent for liquid crystal display elements with ultraviolet rays of 100 mW / cm2for 30 seconds using a metal halide lamp. Subsequently, the liquid crystal display element was produced by performing formal curing by heating at 120°C for 1 hour. 2

[0199] For the obtained liquid crystal display element, alignment disorder (display unevenness) was confirmed using a polarizing microscope (KEYENCE Co., Ltd., "VHX-5000"). The alignment disorder was judged from the color unevenness of the display portion, and the case where no display unevenness was observed at all in the liquid crystal display element was denoted by "D", and the case where display unevenness was confirmed was denoted by "X", and the low liquid crystal contamination was evaluated.

[0200]

[0201] ​

[0202] Industrial applicability

[0203] According to the present application, it is possible to provide a sealant for liquid crystal display elements, which is excellent in storage stability, adhesiveness, and low liquid crystal contamination. In addition, according to the present application, it is possible to provide a liquid crystal display element using the sealant for liquid crystal display elements.

Claims

1. A sealant for liquid crystal display elements, characterized in that, a curable resin and a thermal curing agent, the thermal curing agent contains an adduct of an amine compound having an amino equivalent of 30 or less and an epoxy compound, the content of the adduct of the amine compound having an amino equivalent of 30 or less and the epoxy compound is 6 parts by mass or more relative to 100 parts by mass of the curable resin.

2. The sealant for liquid crystal display elements according to claim 1, wherein the amine compound having an amino equivalent of 30 or less is at least any one of hydrazine and carbazide.

3. The sealant for liquid crystal display elements according to claim 1 or 2, wherein, the adduct of the amine compound having an amino equivalent of 30 or less and the epoxy compound is solid at 25°C.

4. The sealant for a liquid crystal display element according to claim 1 or 2, wherein the epoxy compound is an epoxy compound having a structure derived from a compound having a phenolic hydroxyl group.

5. A liquid crystal display element having a cured product of the sealing agent for a liquid crystal display element according to claim 1, 2, 3 or 4.

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